1
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Peleg E, Teitelbaum Y, Arnon S. Exploring the influence of sediment motion on microplastic deposition in streambeds. Water Res 2024; 249:120952. [PMID: 38101045 DOI: 10.1016/j.watres.2023.120952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 11/09/2023] [Accepted: 11/29/2023] [Indexed: 12/17/2023]
Abstract
Microplastics (MP) of all sizes and densities have been found deposited in streambeds. Several delivery processes were proposed to explain these observations. However, none of the previous studies explored these processes systematically, especially in cases of streambeds made of fine sediments that are regularly in motion. In this study, we quantified the effect of streambed motion on the deposition and accumulation of MP in streambed sediments using particle tracking simulations in a numerical flow and transport model. The model was run for streamwater velocities of 0.1-0.5 m s-1 and median grain sizes of 0.15-0.6 mm. Streambed morphodynamics were estimated from these input parameters using empirical relationships. MP propensity to become trapped in porous media was simulated using a filtration coefficient. For each grain size and streamwater velocity, a wide variety of filtration coefficients was used in simulations in order to predict the fate of particles in the sediment. We found that exchange due to sediment turnover leads to burial and long-term deposition of MP that originally were not expected to enter the bed due to size exclusion. The results also show that in streambeds with fine sediments, localized deposits of MP are expected to occur as a horizontal layer below the moving fraction of the bed (upper layer). However, increasing celerity reduces the depth of MP deposition in the streambed. We conclude that models that do not include the effect of bed motion on MP deposition are likely miscalculating the deposition, retention, resuspensions and long-term accumulation of MP in streambed sediments.
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Affiliation(s)
- Eshel Peleg
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel
| | - Yoni Teitelbaum
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
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2
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Dallmann J, Phillips CB, Teitelbaum Y, Saavedra Cifuentes EY, Sund N, Schumer R, Arnon S, Packman AI. Bedform segregation and locking increase storage of natural and synthetic particles in rivers. Nat Commun 2021; 12:7315. [PMID: 34916488 PMCID: PMC8677759 DOI: 10.1038/s41467-021-27554-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/23/2021] [Indexed: 11/16/2022] Open
Abstract
While the ecological significance of hyporheic exchange and fine particle transport in rivers is well established, these processes are generally considered irrelevant to riverbed morphodynamics. We show that coupling between hyporheic exchange, suspended sediment deposition, and sand bedform motion strongly modulates morphodynamics and sorts bed sediments. Hyporheic exchange focuses fine-particle deposition within and below mobile bedforms, which suppresses bed mobility. However, deposited fines are also remobilized by bedform motion, providing a mechanism for segregating coarse and fine particles in the bed. Surprisingly, two distinct end states emerge from the competing interplay of bed stabilization and remobilization: a locked state in which fine particle deposition completely stabilizes the bed, and a dynamic equilibrium in which frequent remobilization sorts the bed and restores mobility. These findings demonstrate the significance of hyporheic exchange to riverbed morphodynamics and clarify how dynamic interactions between coarse and fine particles produce sedimentary patterns commonly found in rivers.
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Affiliation(s)
- J. Dallmann
- grid.16753.360000 0001 2299 3507Department Mechanical Engineering, Northwestern University, Evanston, IL USA ,grid.428191.70000 0004 0495 7803Center for Preparatory Studies, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - C. B. Phillips
- grid.16753.360000 0001 2299 3507Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL USA ,grid.53857.3c0000 0001 2185 8768Department of Civil and Environmental Engineering, Utah State University, Logan, UT USA
| | - Y. Teitelbaum
- grid.7489.20000 0004 1937 0511Zuckerberg Institute for Water Research, Ben‐Gurion University of the Negev, Beersheba, Israel
| | - Edwin Y. Saavedra Cifuentes
- grid.16753.360000 0001 2299 3507Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL USA
| | - N. Sund
- grid.474431.10000 0004 0525 4843Desert Research Institute, Reno, NV USA
| | - R. Schumer
- grid.474431.10000 0004 0525 4843Desert Research Institute, Reno, NV USA
| | - S. Arnon
- grid.7489.20000 0004 1937 0511Zuckerberg Institute for Water Research, Ben‐Gurion University of the Negev, Beersheba, Israel
| | - A. I. Packman
- grid.16753.360000 0001 2299 3507Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL USA
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3
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Broecker T, Sobhi Gollo V, Fox A, Lewandowski J, Nützmann G, Arnon S, Hinkelmann R. High-Resolution Integrated Transport Model for Studying Surface Water-Groundwater Interaction. Ground Water 2021; 59:488-502. [PMID: 33368208 DOI: 10.1111/gwat.13071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 12/14/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
Transport processes that lead to exchange of mass between surface water and groundwater play a significant role for the ecological functioning of aquatic systems, for hydrological processes and for biogeochemical transformations. In this study, we present a novel integral modeling approach for flow and transport at the sediment-water interface. The model allows us to simultaneously simulate turbulent surface and subsurface flow and transport with the same conceptual approach. For this purpose, a conservative transport equation was implemented to an existing approach that uses an extended version of the Navier-Stokes equations. Based on previous flume studies which investigated the spreading of a dye tracer under neutral, losing and gaining flow conditions the new solver is validated. Tracer distributions of the experiments are in close agreement with the simulations. The simulated flow paths are significantly affected by in- and outflowing groundwater flow. The highest velocities within the sediment are found for losing condition, which leads to shorter residence times compared to neutral and gaining conditions. The largest extent of the hyporheic exchange flow is observed under neutral condition. The new solver can be used for further examinations of cases that are not suitable for the conventional coupled models, for example, if Reynolds numbers are larger than 10. Moreover, results gained with the integral solver provide high-resolution information on pressure and velocity distributions at the rippled streambed, which can be used to improve flow predictions. This includes the extent of hyporheic exchange under varying ambient groundwater flow conditions.
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Affiliation(s)
- Tabea Broecker
- Chair of Water Resources Management and Modeling of Hydrosystems, Technische Universität Berlin, Berlin, Germany
| | - Vahid Sobhi Gollo
- Chair of Water Resources Management and Modeling of Hydrosystems, Technische Universität Berlin, Berlin, Germany
| | - Aryeh Fox
- Department of Environmental Hydrology and Microbiology, Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Israel
| | - Jörg Lewandowski
- Ecohydrology Department, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Geography Department, Humboldt-University Berlin, Berlin, Germany
| | - Gunnar Nützmann
- Ecohydrology Department, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Geography Department, Humboldt-University Berlin, Berlin, Germany
| | - Shai Arnon
- Department of Environmental Hydrology and Microbiology, Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Israel
| | - Reinhard Hinkelmann
- Chair of Water Resources Management and Modeling of Hydrosystems, Technische Universität Berlin, Berlin, Germany
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4
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Peralta-Maraver I, Stubbington R, Arnon S, Kratina P, Krause S, de Mello Cionek V, Leite NK, da Silva ALL, Thomaz SM, Posselt M, Milner VS, Momblanch A, Moretti MS, Nóbrega RLB, Perkins DM, Petrucio MM, Reche I, Saito V, Sarmento H, Strange E, Taniwaki RH, White J, Alves GHZ, Robertson AL. The riverine bioreactor: An integrative perspective on biological decomposition of organic matter across riverine habitats. Sci Total Environ 2021; 772:145494. [PMID: 33581537 DOI: 10.1016/j.scitotenv.2021.145494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
Riverine ecosystems can be conceptualized as 'bioreactors' (the riverine bioreactor) which retain and decompose a wide range of organic substrates. The metabolic performance of the riverine bioreactor is linked to their community structure, the efficiency of energy transfer along food chains, and complex interactions among biotic and abiotic environmental factors. However, our understanding of the mechanistic functioning and capacity of the riverine bioreactor remains limited. We review the state of knowledge and outline major gaps in the understanding of biotic drivers of organic matter decomposition processes that occur in riverine ecosystems, across habitats, temporal dimensions, and latitudes influenced by climate change. We propose a novel, integrative analytical perspective to assess and predict decomposition processes in riverine ecosystems. We then use this model to analyse data to demonstrate that the size-spectra of a community can be used to predict decomposition rates by analysing an illustrative dataset. This modelling methodology allows comparison of the riverine bioreactor's performance across habitats and at a global scale. Our integrative analytical approach can be applied to advance understanding of the functioning and efficiency of the riverine bioreactor as hotspots of metabolic activity. Application of insights gained from such analyses could inform the development of strategies that promote the functioning of the riverine bioreactor across global ecosystems.
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Affiliation(s)
- Ignacio Peralta-Maraver
- Departamento de Ecología, Universidad de Granada, Granada, Spain; Department of Life Sciences, Roehampton University, London, UK.
| | - Rachel Stubbington
- School of Science and Technology, Nottingham Trent University, Nottingham, UK
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Pavel Kratina
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Stefan Krause
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Vivian de Mello Cionek
- Programa de Pós-Graduação em Ciência e Tecnologia Ambiental, Universidade do Vale do Itajaí, Itajaí, Santa Catarina, Brazil
| | - Nei Kavaguichi Leite
- Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Aurea Luiza Lemes da Silva
- Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | | | - Malte Posselt
- Department of Environmental Science, Stockholm University, Stockholm, Sweden
| | | | - Andrea Momblanch
- Cranfield Water Science Institute, Cranfield University, Cranfield, UK
| | - Marcelo S Moretti
- Laboratory of Aquatic Insect Ecology, Universidade Vila Velha, Vila Velha, Espírito Santo, Brazil
| | - Rodolfo L B Nóbrega
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot SL5 7PY, UK
| | | | - Mauricio M Petrucio
- Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Isabel Reche
- Departamento de Ecología, Universidad de Granada, Granada, Spain
| | - Victor Saito
- Departamento de Ciências Ambientais, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Hugo Sarmento
- Department of Hydrobiology, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Emily Strange
- Institute of Environmental Sciences, Leiden University, Leiden, the Netherlands
| | - Ricardo Hideo Taniwaki
- Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas, Universidade Federal do ABC, Santo André, São Paulo, Brazil
| | - James White
- River Restoration Centre, Cranfield University, Cranfield, Bedfordshire, UK
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5
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Peralta-Maraver I, Galloway J, Posselt M, Arnon S, Reiss J, Lewandowski J, Robertson AL. Author Correction: Environmental filtering and community delineation in the streambed ecotone. Sci Rep 2019; 9:9509. [PMID: 31239495 PMCID: PMC6593097 DOI: 10.1038/s41598-019-45692-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
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Affiliation(s)
| | - Jason Galloway
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department Ecohydrology, Berlin, Germany.,Geography Department, Humboldt University, Berlin, Germany
| | - Malte Posselt
- Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm, Sweden
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Julia Reiss
- Department of Life Sciences, Roehampton University, London, UK
| | - Jörg Lewandowski
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department Ecohydrology, Berlin, Germany.,Geography Department, Humboldt University, Berlin, Germany
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6
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Zaibel I, Appelbaum Y, Arnon S, Britzi M, Schwartsburd F, Snyder S, Zilberg D. The effect of tertiary treated wastewater on fish growth and health: Laboratory-scale experiment with Poecilia reticulata (guppy). PLoS One 2019; 14:e0217927. [PMID: 31185032 PMCID: PMC6559704 DOI: 10.1371/journal.pone.0217927] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 05/21/2019] [Indexed: 12/24/2022] Open
Abstract
Treated wastewater (TWW) constitutes a sustainable water resource and has been used for fish culture in some countries around the world, although there are no comprehensive data on the effect of TWW on fish growth and health in the context of aquaculture production. Our objectives were to examine how fish culture in TWW affected fish growth and fitness, as well as compliance with the international standards for safe consumption. Guppy (Poecilia reticulata) fingerlings were reared in 0%, 50% and 100% tertiary TWW (TTWW), from the age of five days, for a period of four months. In water analyses, 33 out of 67 tested organic micropollutants (OMPs) were detected in the TTWW samples at least once, at concentrations that are typically reported in domestic TTWW. Fish survival ranged between 77-80% and did not differ between treatment groups. Fish growth and mortality following challenge infection with Tetrahymena sp. (which ranged between 64-68%), were similar among treatment groups. Of tested immunological parameters, lysozyme and anti-protease was similar among treatments while complement activity was highest in the 50% TTWW-reared fish. No abnormalities were observed in the histopathological analysis. Levels of heavy metals, polychlorinated-biphenyls (PCBs) and organochlorines (OCs) in fish were below the detection limit and below the Food and Agriculture Organization of the United Nations (FAO) and the European Union EU maximal permitted levels in food fish. Results suggest that the yield of fish grown in TTWW is potentially similar to that in freshwater, and the produced fish comply with the standards of consumer safety. The results are in line with previous studies that examined the feasibility of TWW-fed aquaculture.
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Affiliation(s)
- Inbal Zaibel
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Yuval Appelbaum
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Malka Britzi
- The National Residue Control Laboratory, The Kimron Veterinary Institute, Ministry of Agriculture, Beit Dagan, Israel
| | - Frieda Schwartsburd
- The National Residue Control Laboratory, The Kimron Veterinary Institute, Ministry of Agriculture, Beit Dagan, Israel
| | - Shane Snyder
- Department of Chemical & Environmental Engineering, University of Arizona, Tucson, Arizona, United States of America
| | - Dina Zilberg
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
- * E-mail:
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7
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Shumilova O, Zak D, Datry T, von Schiller D, Corti R, Foulquier A, Obrador B, Tockner K, Allan DC, Altermatt F, Arce MI, Arnon S, Banas D, Banegas‐Medina A, Beller E, Blanchette ML, Blanco‐Libreros JF, Blessing J, Boëchat IG, Boersma K, Bogan MT, Bonada N, Bond NR, Brintrup K, Bruder A, Burrows R, Cancellario T, Carlson SM, Cauvy‐Fraunié S, Cid N, Danger M, de Freitas Terra B, Girolamo AMD, del Campo R, Dyer F, Elosegi A, Faye E, Febria C, Figueroa R, Four B, Gessner MO, Gnohossou P, Cerezo RG, Gomez‐Gener L, Graça MA, Guareschi S, Gücker B, Hwan JL, Kubheka S, Langhans SD, Leigh C, Little CJ, Lorenz S, Marshall J, McIntosh A, Mendoza‐Lera C, Meyer EI, Miliša M, Mlambo MC, Moleón M, Negus P, Niyogi D, Papatheodoulou A, Pardo I, Paril P, Pešić V, Rodriguez‐Lozano P, Rolls RJ, Sanchez‐Montoya MM, Savić A, Steward A, Stubbington R, Taleb A, Vorste RV, Waltham N, Zoppini A, Zarfl C. Simulating rewetting events in intermittent rivers and ephemeral streams: A global analysis of leached nutrients and organic matter. Glob Chang Biol 2019; 25:1591-1611. [PMID: 30628191 PMCID: PMC6850495 DOI: 10.1111/gcb.14537] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 10/07/2018] [Indexed: 06/01/2023]
Abstract
Climate change and human pressures are changing the global distribution and the extent of intermittent rivers and ephemeral streams (IRES), which comprise half of the global river network area. IRES are characterized by periods of flow cessation, during which channel substrates accumulate and undergo physico-chemical changes (preconditioning), and periods of flow resumption, when these substrates are rewetted and release pulses of dissolved nutrients and organic matter (OM). However, there are no estimates of the amounts and quality of leached substances, nor is there information on the underlying environmental constraints operating at the global scale. We experimentally simulated, under standard laboratory conditions, rewetting of leaves, riverbed sediments, and epilithic biofilms collected during the dry phase across 205 IRES from five major climate zones. We determined the amounts and qualitative characteristics of the leached nutrients and OM, and estimated their areal fluxes from riverbeds. In addition, we evaluated the variance in leachate characteristics in relation to selected environmental variables and substrate characteristics. We found that sediments, due to their large quantities within riverbeds, contribute most to the overall flux of dissolved substances during rewetting events (56%-98%), and that flux rates distinctly differ among climate zones. Dissolved organic carbon, phenolics, and nitrate contributed most to the areal fluxes. The largest amounts of leached substances were found in the continental climate zone, coinciding with the lowest potential bioavailability of the leached OM. The opposite pattern was found in the arid zone. Environmental variables expected to be modified under climate change (i.e. potential evapotranspiration, aridity, dry period duration, land use) were correlated with the amount of leached substances, with the strongest relationship found for sediments. These results show that the role of IRES should be accounted for in global biogeochemical cycles, especially because prevalence of IRES will increase due to increasing severity of drying events.
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Affiliation(s)
- Oleksandra Shumilova
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB)BerlinGermany
- Institute of BiologyFreie Universität Berlin (FU)BerlinGermany
- Department of CivilEnvironmental and Mechanical EngineeringTrento UniversityTrentoItaly
| | - Dominik Zak
- Institute of BiologyFreie Universität Berlin (FU)BerlinGermany
- Institute of Landscape Ecology and Site EvaluationUniversity of RostockRostockGermany
- Department of BioscienceAarhus UniversitySilkeborgDenmark
| | - Thibault Datry
- IRSTEAUR RIVERLYCentre de Lyon‐VilleurbanneVilleurbanne CedexFrance
| | - Daniel von Schiller
- Department of Plant Biology and EcologyFaculty of Science and TechnologyUniversity of the Basque Country (UPV/EHU)BilbaoSpain
| | - Roland Corti
- IRSTEAUR RIVERLYCentre de Lyon‐VilleurbanneVilleurbanne CedexFrance
| | - Arnaud Foulquier
- Laboratoire d’Écologie Alpine (LECA)UMR CNRS‐UGA‐USMB 5553Université Grenoble AlpesGrenobleFrance
| | - Biel Obrador
- Department of Evolutionary Biology, Ecology and Environmental SciencesFaculty of BiologyBiodiversity Research Institute (IRBIO)University of BarcelonaBarcelonaSpain
| | - Klement Tockner
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB)BerlinGermany
- Institute of BiologyFreie Universität Berlin (FU)BerlinGermany
- Austrian Science Fund (FWF)ViennaAustria
| | | | - Florian Altermatt
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZürichSwitzerland
| | - María Isabel Arce
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB)BerlinGermany
- Centre of Edaphology and Applied Biology of Segura (CEBAS‐CSIC)MurciaSpain
| | - Shai Arnon
- Zuckerberg Institute for Water ResearchThe Jacob Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevBeershebaIsrael
| | - Damien Banas
- Université de Lorraine ‐ UR AFPAVandoeuvre‐Les‐NancyFrance
| | - Andy Banegas‐Medina
- Faculty of Environmental Science and EULA‐Chile CenterUniversidad de ConcepciónConcepciónChile
| | - Erin Beller
- Department of GeographyUniversity of CaliforniaBerkeleyCalifornia
| | - Melanie L. Blanchette
- Mine Water and Environment Research Centre (MiWER)School of ScienceEdith Cowan UniversityPerthAustralia
| | | | - Joanna Blessing
- Department of Environment and ScienceQueensland GovernmentBrisbaneQldAustralia
| | | | - Kate Boersma
- Department of BiologyUniversity of San DiegoSan DiegoCalifornia
| | - Michael T. Bogan
- School of Natural Resources and the EnvironmentUniversity of ArizonaTucsonArizona
| | - Núria Bonada
- Grup de Recerca Freshwater Ecology, Hydrology and Management (FEHM)Departament de Biologia EvolutivaEcologia i Ciències AmbientalsInstitut de Recerca de la Biodiversitat (IRBio)Universitat de BarcelonaBarcelonaSpain
| | - Nick R. Bond
- Centre for Freshwater EcosystemsLa Trobe UniversityWodongaVic.Australia
| | - Kate Brintrup
- Faculty of Environmental Science and EULA‐Chile CenterUniversidad de ConcepciónConcepciónChile
| | - Andreas Bruder
- Laboratory of Applied MicrobiologyUniversity of Applied Sciences and Arts of Southern SwitzerlandBellinzonaSwitzerland
| | - Ryan Burrows
- Australian Rivers InstituteGriffith UniversityNathanQldAustralia
| | - Tommaso Cancellario
- Department of Environmental BiologyBiodiversity Data Analytics and Environmental Quality GroupUniversity of NavarraPamplonaSpain
| | - Stephanie M. Carlson
- Department of Environmental Science, Policy, and ManagementUniversity of CaliforniaBerkeleyCalifornia
| | | | - Núria Cid
- Grup de Recerca Freshwater Ecology, Hydrology and Management (FEHM)Departament de Biologia EvolutivaEcologia i Ciències AmbientalsInstitut de Recerca de la Biodiversitat (IRBio)Universitat de BarcelonaBarcelonaSpain
| | | | | | - Anna Maria De Girolamo
- Water Research Institute – National Research Council (IRSA‐CNR)Montelibretti (Rome)Italy
| | - Ruben del Campo
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB)BerlinGermany
- Department of Ecology and HydrologyRegional Campus of International Excellence ‘Campus Mare Nostrum’ – University of MurciaMurciaSpain
| | - Fiona Dyer
- Institute for Applied EcologyUniversity of CanberraBruceCanberra ACTAustralia
| | - Arturo Elosegi
- Department of Plant Biology and EcologyFaculty of Science and TechnologyUniversity of the Basque Country (UPV/EHU)BilbaoSpain
| | - Emile Faye
- Centre International de Recherche en Agronomie pour le DéveloppementCIRADUPR HortSysMontpellierFrance
| | - Catherine Febria
- School of Biological SciencesUniversity of CanterburyChristchurchNew Zealand
- Great Lakes Institute for Environmental ResearchUniversity of WindsorWindsorCanada
| | - Ricardo Figueroa
- Faculty of Environmental Science and EULA‐Chile CenterUniversidad de ConcepciónConcepciónChile
| | - Brian Four
- INRAUAR 1275 DEPT EFPACentre de recherche de NancyChampenouxFrance
| | - Mark O. Gessner
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB)BerlinGermany
- Department of EcologyBerlin Institute of Technology (TU Berlin)BerlinGermany
| | - Pierre Gnohossou
- Faculté d'AgronomieDépartement d'Aménagement et de Gestion des Ressources NaturellesUniversité de ParakouParakouBenin
| | - Rosa Gómez Cerezo
- Department of Ecology and HydrologyRegional Campus of International Excellence ‘Campus Mare Nostrum’ – University of MurciaMurciaSpain
| | - Lluís Gomez‐Gener
- Department of Ecology and Environmental ScienceUmeå UniversityUmeåSweden
| | - Manuel A.S. Graça
- MARE – Marine and Environmental Sciences CentreDepartment of Life SciencesUniversity of CoimbraCoimbraPortugal
| | - Simone Guareschi
- Department of Ecology and HydrologyRegional Campus of International Excellence ‘Campus Mare Nostrum’ – University of MurciaMurciaSpain
| | - Björn Gücker
- Department of GeosciencesFederal University of São João del‐ReiSão João del‐ReiBrazil
| | - Jason L. Hwan
- Department of Environmental Science, Policy, and ManagementUniversity of CaliforniaBerkeleyCalifornia
| | | | - Simone Daniela Langhans
- Department of ZoologyUniversity of OtagoDunedinNew Zealand
- BC3‐Basque Centre for Climate ChangeLeioaSpain
| | - Catherine Leigh
- Australian Rivers InstituteGriffith UniversityNathanQldAustralia
- ARC Centre of Excellence for Mathematical & Statistical Frontiers (ACEMS) and Institute for Future EnvironmentsSchool of Mathematical SciencesQueensland University of TechnologyBrisbaneQldAustralia
| | - Chelsea J. Little
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZürichSwitzerland
- Department of Aquatic Ecology, EawagThe Swiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
| | - Stefan Lorenz
- Institute for Ecological ChemistryPlant Analysis and Stored Product ProtectionJulius‐Kuehn‐InstituteBerlinGermany
| | - Jonathan Marshall
- Department of Environment and ScienceQueensland GovernmentBrisbaneQldAustralia
- Australian Rivers InstituteGriffith UniversityNathanQldAustralia
| | - Angus McIntosh
- School of Biological SciencesUniversity of CanterburyChristchurchNew Zealand
| | - Clara Mendoza‐Lera
- IRSTEAUR RIVERLYCentre de Lyon‐VilleurbanneVilleurbanne CedexFrance
- Department of Freshwater ConservationBTU Cottbus‐SenftenbergBad SaarowGermany
| | | | - Marko Miliša
- Department of BiologyFaculty of ScienceUniversity of ZagrebZagrebCroatia
| | - Musa C. Mlambo
- Department of Freshwater InvertebratesAlbany MuseumAffiliated Research Institute of Rhodes UniversityGrahamstownSouth Africa
| | - Marcos Moleón
- Department of ZoologyUniversity of GranadaGranadaSpain
| | - Peter Negus
- Department of Environment and ScienceQueensland GovernmentBrisbaneQldAustralia
| | - Dev Niyogi
- Missouri University of Science and TechnologyRollaMissouri
| | | | - Isabel Pardo
- Departamento de Ecología y Biología AnimalUniversidad de VigoVigoSpain
| | - Petr Paril
- Department of Botany and ZoologyFaculty of ScienceMasaryk UniversityBrnoCzech Republic
| | - Vladimir Pešić
- Department of BiologyUniversity of MontenegroPodgoricaMontenegro
| | - Pablo Rodriguez‐Lozano
- Department of Environmental Science, Policy, and ManagementUniversity of CaliforniaBerkeleyCalifornia
| | - Robert J. Rolls
- School of Environmental and Rural ScienceUniversity of New EnglandArmidaleNSWAustralia
| | - Maria Mar Sanchez‐Montoya
- Department of Ecology and HydrologyRegional Campus of International Excellence ‘Campus Mare Nostrum’ – University of MurciaMurciaSpain
| | - Ana Savić
- Department of Biology and EcologyFaculty of Sciences and MathematicsUniversity of NišNišSerbia
| | - Alisha Steward
- Department of Environment and ScienceQueensland GovernmentBrisbaneQldAustralia
- Australian Rivers InstituteGriffith UniversityNathanQldAustralia
| | | | - Amina Taleb
- Laboratoire d’Écologie et Gestion des Ecosystèmes Naturels (LECGEN)University of TlemcenTlemcenAlgeria
| | - Ross Vander Vorste
- Department of Environmental Science, Policy, and ManagementUniversity of CaliforniaBerkeleyCalifornia
| | - Nathan Waltham
- TropWATER (Centre for Tropical Water and Aquatic Ecosystem Research)College of Science and EngineeringJames Cook UniversityTownsvilleQldAustralia
| | - Annamaria Zoppini
- Water Research Institute – National Research Council (IRSA‐CNR)Montelibretti (Rome)Italy
| | - Christiane Zarfl
- Center for Applied GeosciencesEberhard Karls Universität TübingenTübingenGermany
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8
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Bykhovsky D, Arnon S. Performance of spectral amplitude coded multiple pulse position modulation with non-uniform energy slots and fading. Opt Express 2018; 26:29225-29230. [PMID: 30470088 DOI: 10.1364/oe.26.029225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 07/22/2018] [Indexed: 06/09/2023]
Abstract
Multiple-pulse position modulation (MPPM) is an advanced modulation method for optical wireless communication (OWC), which could provide better performance when channel information is not available. We consider the evaluation of a symbol error rate (SER) expression for MPPM applied within OWC. In the proposed model, MPPM is realized by spectral-amplitude coding (SAC) with non-uniform spectral slot energies. The derived fading channel SER expression is applicable for an arbitrary fading distribution, which may be due to either atmospheric turbulence or transceiver pointing error. A detailed theoretical analysis of the SER is provided and the resulting SER expression is verified by simulation.
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9
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Peralta-Maraver I, Galloway J, Posselt M, Arnon S, Reiss J, Lewandowski J, Robertson AL. Environmental filtering and community delineation in the streambed ecotone. Sci Rep 2018; 8:15871. [PMID: 30367095 PMCID: PMC6203860 DOI: 10.1038/s41598-018-34206-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 10/15/2018] [Indexed: 12/04/2022] Open
Abstract
A current controversy in ecology is whether biological communities are discrete biological entities or simply study units created for convenience; a debate that becomes even more heated when delimiting communities along ecotones. Here, we report an interdisciplinary study designed to address the interplay between environmental drivers and community ecology in a typical ecotone ecosystem: the streambed. Environmental filtering at a micro-scale determined how diversity, productivity and composition of the whole streambed assemblage varied with depth and with the direction of vertical water exchange. Biomass and production decreased with increasing depth, and were lower under upwelling than downwelling conditions. However, the rate at which biomass and production decreased with increasing depth differed significantly for different taxonomic groups. Using quantitative biocenosis analysis, we also showed that benthic and hyporheic zone assemblages (assemblages in close juxtaposition) could be clearly distinguished as discrete communities with individual integrity. Vertical hydrodynamic conditions also influenced the demarcation between both communities; the benthic community reached greater depths in downwelling than in upwelling zones.
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Affiliation(s)
| | - Jason Galloway
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department Ecohydrology, Berlin, Germany.,Geography Department, Humboldt University, Berlin, Germany
| | - Malte Posselt
- Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm, Sweden
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Julia Reiss
- Department of Life Sciences, Roehampton University, London, UK
| | - Jörg Lewandowski
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department Ecohydrology, Berlin, Germany.,Geography Department, Humboldt University, Berlin, Germany
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10
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Dotan P, Yeshayahu M, Odeh W, Gordon-Kirsch N, Groisman L, Al-Khateeb N, Abed Rabbo A, Tal A, Arnon S. Endocrine disrupting compounds in streams in Israel and the Palestinian West Bank: Implications for transboundary basin management. J Environ Manage 2017; 204:355-364. [PMID: 28915473 DOI: 10.1016/j.jenvman.2017.09.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/30/2017] [Accepted: 09/06/2017] [Indexed: 06/07/2023]
Abstract
Endocrine disrupting compounds (EDCs) frequently enter surface waters via discharges from wastewater treatment plants (WWTPs), as well as from industrial and agricultural activities, creating environmental and health concerns. In this study, selected EDCs were measured in water and sediments along two transboundary streams flowing from the Palestinian Authority (PA) into Israel (the Zomar-Alexander and Hebron-Beer Sheva Streams). We assessed how the complicated conflict situation between Israel and the PA and the absence of a coordinated strategy and joint stream management commission influence effective EDC control. Both streams receive raw Palestinian wastewater in their headwaters, which flows through rural areas and is treated via sediment settling facilities after crossing the 1949 Armistice Agreement Line. Four sampling campaigns were conducted over two years, with concentrations of selected EDCs measured in both the water and the sediments. Results show asymmetrical pollution profiles due to socio-economic differences and contrasting treatment capacities. No in-stream attenuation was observed along the stream and in the sediments within the Palestinian region. After sediment settling in treatment facilities at the Israeli border, however, significant reductions in the EDC concentrations were measured both in the sediments and in the water. Differences in sedimentation technologies had a substantial effect on EDC removal at the treatment location, positively affecting the streams' ability to further remove EDCs downstream. The prevailing approach to addressing the Israeli-Palestinian transboundary wastewater contamination reveals a narrow perspective among water managers who on occasion only take local interests into consideration, with interventions focused solely on improving stream water quality in isolated segments. Application of the "proximity principle" through the establishment of WWTPs at contamination sources constitutes a preferable strategy for reducing contamination by EDCs and other pollutants to ensure minimization of public health risks due to the pollution of streams and underlying potable groundwater.
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Affiliation(s)
- Pniela Dotan
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel
| | - Maayan Yeshayahu
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel
| | - Wa'd Odeh
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel
| | - Nina Gordon-Kirsch
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel
| | - Ludmila Groisman
- National Public Health Laboratory, Ministry of Health, Tel Aviv, Israel
| | - Nader Al-Khateeb
- Water & Environmental Development Organization, PO Box 421, Bethlehem, Palestine
| | - Alfred Abed Rabbo
- Water & Soil Environmental Research Unit (WSERU), Chemistry Department, Bethlehem University, P.O. Box 9, Bethlehem, Palestine
| | - Alon Tal
- Institute for Dryland Environmental Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel.
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Dotan P, Tal A, Arnon S. Corrigendum to "A simple model for estimating the concentrations of natural estrogens in raw wastewater" [Sci. Total Environ. 575 (2017) 588-594]. Sci Total Environ 2017; 587-588:522. [PMID: 28242225 DOI: 10.1016/j.scitotenv.2017.02.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Pniela Dotan
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel
| | - Alon Tal
- Swiss Institute for Dryland Environmental and Energy Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
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12
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Dotan P, Tal A, Arnon S. A simple model for estimating the concentrations of natural estrogens in raw wastewater. Sci Total Environ 2017; 575:588-594. [PMID: 27622697 DOI: 10.1016/j.scitotenv.2016.09.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 08/31/2016] [Accepted: 09/02/2016] [Indexed: 06/06/2023]
Abstract
This study provides a tool for predicting the concentrations of the natural estrogens (NEs) estrone, 17β-estradiol and estriol in raw wastewater (WW). Data characterizing the biochemical oxygen demand (BOD), NE concentrations, and discharges of raw sewage to wastewater treatment plants (WWTPs) were collected from various publications and used in the model formulation. A strong correlation was found between the log transformed BOD and the log transformed estrone load (r2=0.84, n=61), the log transformed 17β-estradiol load (r2=0.89, n=52) and the log transformed estriol load (r2=0.80, n=40). The models are reasonably accurate when compared to the measured concentrations and slightly better than previous modeling efforts. The relative amounts of data falling within ±50% error were 67% for estrone, 63% for 17β-estradiol, and 55% for estriol. Because the model was developed from a wide array of WWTPs from five continents, it is universal and can be used for projecting concentrations of NEs from a wide range of mixed domestic and industrial sources, but may be less precise when sources contain high levels of NEs or BOD (e.g., WW from dairy farms and food processing plants). The model is expected to improve our ability to predict the fate of NEs in WWTPs and in the receiving environment, which currently relies on estimating the concentrations of NEs in raw wastewater. Its application is especially valuable since direct measurement of NEs in raw WW is expensive and practically impossible in many developing countries due to the lack of expertise and funds.
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Affiliation(s)
- Pniela Dotan
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel
| | - Alon Tal
- Swiss Institute for Dryland Environmental and Energy Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
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Zaibel I, Zilberg D, Groisman L, Arnon S. Impact of treated wastewater reuse and floods on water quality and fish health within a water reservoir in an arid climate. Sci Total Environ 2016; 559:268-281. [PMID: 27065446 DOI: 10.1016/j.scitotenv.2016.03.099] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/14/2016] [Accepted: 03/14/2016] [Indexed: 06/05/2023]
Abstract
Treated wastewater (TWW) reuse for agricultural irrigation is a well-established approach to coping with water shortages in semi-arid and arid environments. Recently, additional uses of TWW have emerged, including streamflow augmentation and aquatic ecosystem restoration. The purpose of the current study was to evaluate the water quality and fish health, in an artificial reservoir located in an arid climate (the Yeruham Reservoir, Israel), which regularly receives TWW and sporadic winter floods. The temporal distribution of water levels, nutrients and organic micropollutants (OMPs) were measured during the years 2013-2014. OMPs were also measured in sediment and fish tissues. Finally, the status of fish health was evaluated by histopathology. Water levels and quality were mainly influenced by seasonal processes such as floods and evaporation, and not by the discharge of TWW. Out of 16 tested OMPs, estrone, carbamazepine, diclofenac and bezafibrate were found in the reservoir water, but mostly at concentrations below the predicted no-effect concentration (PNEC) for fish. Concentrations of PCBs and dioxins in fish muscle and liver were much lower than the EU maximal permitted concentrations, and similar to concentrations that were found in food fish in Israel and Europe. In the histopathological analysis, there were no evident tissue abnormalities, and low to moderate infection levels of fish parasites were recorded. The results from the Yeruham Reservoir demonstrated a unique model for the mixture effect between TWW reuse and natural floods to support a unique stable and thriving ecosystem in a water reservoir located in an arid region. This type of reservoir can be widely used for recreation, education, and the social and economic development of a rural environment, such as has occurred in the Yeruham region.
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Affiliation(s)
- Inbal Zaibel
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel; French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel
| | - Dina Zilberg
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel
| | | | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel
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14
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Dotan P, Godinger T, Odeh W, Groisman L, Al-Khateeb N, Rabbo AA, Tal A, Arnon S. Occurrence and fate of endocrine disrupting compounds in wastewater treatment plants in Israel and the Palestinian West Bank. Chemosphere 2016; 155:86-93. [PMID: 27107387 DOI: 10.1016/j.chemosphere.2016.04.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 04/07/2016] [Accepted: 04/08/2016] [Indexed: 06/05/2023]
Abstract
Israel and its Palestinian neighbors constitute a unique venue for evaluating the treatment efficiency and potential environmental risks of endocrine disrupting compounds (EDCs) in wastewater treatment plants (WWTPs), because of their physical proximity yet contrasting societal dynamics. Israel primarily relies on advanced tertiary sewage treatment and recycles over 85% of its treated wastewater, while in the Palestinian Authority (PA), there is only secondary treatment levels at WWTPs and reuse is minimal (<1%). To evaluate the extent of EDC occurrence and treatment efficiency, we conducted four sampling campaigns over two consecutive years, and measured the concentrations of selected EDCs in raw wastewater (WW), treated WW and sludge in six WWTPs in Israel, as well as in two Palestinian plants. Low concentrations of bisphenol A, octylphenol and triclosan measured in the raw WW in the Palestinian WWTPs reflected the relatively modest industrial activity and consumption habits as compared to the westernized consumer patterns in Israel. On the other hand, hormone concentrations in raw WW were higher in the Palestinian WWTPs than those in the Israeli WWTPs, presumably because of a dilution effect associated with a higher water per capita consumption among Israelis. Despite these differences in raw WW concentrations, the removal efficiency in all advanced WWTPs was relatively high when compared to averages reported internationally.
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Affiliation(s)
- Pniela Dotan
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel
| | - Tal Godinger
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel
| | - Wad Odeh
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel
| | - Ludmila Groisman
- National Public Health Laboratory, Ministry of Health, Tel Aviv, Israel
| | - Nader Al-Khateeb
- Water & Environmental Development Organization, P.O. Box 421, Bethlehem, Palestine
| | - Alfred Abed Rabbo
- Water & Soil Environmental Research Unit (WSERU), Chemistry Department, Bethlehem University, P.O. Box 9, Bethlehem, Palestine
| | - Alon Tal
- Institute for Dryland Environmental Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, 84990, Israel.
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Futran Fuhrman V, Tal A, Arnon S. Why endocrine disrupting chemicals (EDCs) challenge traditional risk assessment and how to respond. J Hazard Mater 2015; 286:589-611. [PMID: 25646754 DOI: 10.1016/j.jhazmat.2014.12.012] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 12/02/2014] [Accepted: 12/08/2014] [Indexed: 05/11/2023]
Abstract
Endocrine disrupting compounds (EDCs) are a diverse group of "chemicals of emerging concern" which have attracted much interest from the research community since the 1990s. Today there is still no definitive risk assessment tool for EDCs. While some decision making organizations have attempted to design methodology guidelines to evaluate the potential risk from this broadly defined group of constituents, risk assessors still face many uncertainties and unknowns. Until a risk assessment paradigm is designed specifically for EDCs and is vetted by the field, traditional risk assessment tools may be used with caution to evaluate EDCs. In doing so, each issue of contention should be addressed with transparency in order to leverage available information and technology without sacrificing integrity or accuracy. The challenges that EDCs pose to traditional risk assessment are described in this article to assist in this process.
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Affiliation(s)
- Vivian Futran Fuhrman
- Institute for Dryland, Environmental and Desert Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
| | - Alon Tal
- Institute for Dryland, Environmental and Desert Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
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Yanuka-Golub K, Arnon S, Nejidat A. Impact of streambed morphology on the abundance and activity of ammonia-oxidizing bacteria. FEMS Microbiol Ecol 2014; 90:175-83. [PMID: 25056670 DOI: 10.1111/1574-6941.12385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 06/24/2014] [Accepted: 07/08/2014] [Indexed: 12/01/2022] Open
Abstract
Ammonia oxidizers catalyze the first step of nitrification. Combined microbial nitrification-denitrification activities are essential for the removal of excess nitrogen from water bodies. In sandy streambeds, bed form structures are created by water flow and lead to the creation of heterogeneous microenvironments. The objective of this study, therefore, was to investigate the effect of bed form morphology on the abundance and activity of ammonia-oxidizing bacteria (AOB) within a benthic biofilm. An 8-month-old benthic biofilm was established in a recirculating laboratory flume under controlled flow conditions and frequent amendment with ammonium. The sand bed was arranged into bed form structures. The highest concentrations of chlorophyll a (indicative of algae) were measured on the upstream side of the bed forms. The biofilm was dominated by Nitrosospira species, and amoA gene abundance was higher on the downstream sides of the bed forms with no significant difference in oxygen consumption between the upstream and downstream sections of the bed form. In contrast, potential ammonium oxidation rates were higher on the upstream sides of the bed forms. The results suggest that bed form morphology can affect the spatial distribution and activity of AOB, possibly through the creation of distinct microhabitats. These results contribute to our understanding of nitrogen transformations and removal from streams.
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Affiliation(s)
- Keren Yanuka-Golub
- Department of Environmental Hydrology & Microbiology, Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, Israel
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Baram S, Arnon S, Ronen Z, Kurtzman D, Dahan O. Infiltration mechanism controls nitrification and denitrification processes under dairy waste lagoon. J Environ Qual 2012; 41:1623-1632. [PMID: 23099954 DOI: 10.2134/jeq2012.0015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Earthen waste lagoons are commonly used to store liquid wastes from concentrated animal feeding operations. The fate of ammonium (NH) and nitrate (NO) was studied in the vadose zone below earthen-clay dairy farm waste lagoons using three independent vadose zone monitoring systems. The vadose zone was monitored from 0.5 to 30 m below land surface through direct sampling of the sediment porewater and continuous measurement of the sediment profile's water content variations. Four years of monitoring revealed that wastewater infiltration from the lagoon is controlled by two mechanisms: slow (mm d), constant infiltration from the lagoon bed; and rapid (m h) infiltration of wastewater and rainwater via preferential flow in desiccation cracks formed in the unsaturated clay sediment surrounding the lagoon banks. The preferential flow mechanism is active mainly during wastewater-level fluctuations and intensive rain events. The vadose zone below the waste sources remained unsaturated throughout the monitoring period, and all infiltrating NH was oxidized in the upper 0.5 m. The NH oxidation (nitrification) was coupled with NO reduction (denitrification) and depended on the sediment water content, which was controlled by the infiltration mechanism. Coupled nitrification-denitrification (CND) resulted in 90 to 100% reduction in the total nitrogen mass in the vadose zone, with higher removal under high water content (∼0.55 m m). Mass balance of nitrogen and isotopic composition of NO indicated that CND, rather than cation exchange capacity, is the key factor regulating nitrogen's fate in the vadose zone underlying earthen waste lagoons.
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Affiliation(s)
- S Baram
- Department of Environmental Hydrology & Microbiology, Zuckerberg Institute of Water Research, Israel.
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Arnon S, Dolfin T, Bauer S, Regev RH, Litmanovitz I. Iron supplementation for preterm infants receiving restrictive red blood cell transfusions: reassessment of practice safety. J Perinatol 2010; 30:736-40. [PMID: 20220759 DOI: 10.1038/jp.2010.33] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To reassess iron supplementation practice safety in very low birth weight (VLBW) preterm infants receiving restrictive red blood cell transfusions during initial hospitalization. STUDY DESIGN Iron status, including hemoglobin (Hb), serum iron, ferritin, and soluble transferrin receptor (sTfR) levels and reticulocyte count of transfused (n=236) and non-transfused (n=166) preterm infants at ≤24 h and 2, 4 and 8 weeks were recorded. As per protocol, a restrictive blood transfusion policy and supplementation of 5 mg kg(-1) per day of iron polymaltose complex from 4 weeks and 25 mg(-1) per day of vitamin E from 2 weeks were imposed for all infants. Normative reference cord-blood ferritin value of preterm infants was used for comparison. Vitamin E levels and incidence of morbidities associated with prematurity were recorded. RESULT At ≤24 h, the characteristics and iron status of both groups were similar. At 2, 4 and 8 weeks, the transfused group had significantly higher Hb, iron and ferritin levels; sTfR levels were lower at 4 and 8 weeks (all indices, P<0.05). At 8 weeks, the median ferritin levels of our transfused group were lower than that of normative reference cord-blood value (115 (50th percentile) vs 79 (43 to 107) μg l(-1), respectively). Vitamin E levels and the incidence of morbidities associated with prematurity of the transfused and non-transfused groups were not different (both indices, P>0.18). CONCLUSION Adding iron supplementation to preterm infants receiving restrictive blood transfusions has shown to be a judicious and safe practice in terms of iron status for VLBW preterm infants.
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Affiliation(s)
- S Arnon
- Department of Neonatology, Meir Medical Center, Kfar Saba, Israel.
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Gilad E, Arnon S. The Role of Live Music and Singing as a Stress-Reducing Modality in the Neonatal Intensive Care Unit Environment. ACTA ACUST UNITED AC 2009. [DOI: 10.1177/1943862109357070] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Regev RH, Markovich O, Arnon S, Bauer S, Dolfin T, Litmanovitz I. Meconium periorchitis: intrauterine diagnosis and neonatal outcome: case reports and review of the literature. J Perinatol 2009; 29:585-7. [PMID: 19638993 DOI: 10.1038/jp.2009.15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Meconium periorchitis (MP) is a rare disorder caused by fetal meconium peritonitis with subsequent spillage of meconium into the scrotal sac. The condition is seldom diagnosed correctly during fetal life and the ultrasonographic diagnoses reported vary from no diagnosis to hematoma or hydrocele. It is usually diagnosed clinically during the first year of life when a scrotal mass is an incidental finding. Here, we describe two cases of MP that were diagnosed during routine intrauterine ultrasound examination for fetal growth assessment, and confirmed after birth. One infant underwent a surgical excision of the scrotal mass, confirming the histological diagnosis of meconium periorchitis. The other was managed conservatively. Neither had cystic fibrosis. Thus, we believe that a diagnosis of MP should be considered when prenatal ultrasonographic findings are suspicious for the problem. The awareness of the ultrasonographer and the neonatologist are important for immediate postnatal management, as congenital scrotal masses may have other etiologies.
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Affiliation(s)
- R H Regev
- Neonatal Department, Meir Medical Center, Kfar Saba 44821, Israel.
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Arnon S, Dahan O, Elhanany S, Cohen K, Pankratov I, Gross A, Ronen Z, Baram S, Shore LS. Transport of testosterone and estrogen from dairy-farm waste lagoons to groundwater. Environ Sci Technol 2008; 42:5521-5526. [PMID: 18754470 DOI: 10.1021/es800784m] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Although concentrated animal feeding operations constantly generate physiologically active steroidal hormones, little is known of their environmental fate. Estrogen and testosterone concentrations in groundwater and their distribution in sediments below a dairy-farm wastewater lagoon were therefore determined and compared to a reference site located upgradient of the farm. Forward simulations of flow as well as estrogen and testosterone transport were conducted based on data from the sediment profile obtained during drilling of a monitoring well belowthe dairy-farm waste lagoon. Testosterone and estrogen were detected in sediments to depths of 45 and 32 m, respectively. Groundwater samples were directly impacted by the dairy farm, as evidenced by elevated concentrations of nitrate, chloride, testosterone, and estrogen as compared to the reference site. Modeling potential transport of hormones in the vadose zone via advection, dispersion, and sorption could not explain the depths at which estrogen and testosterone were found, suggesting that other transport mechanisms influence hormone transport under field conditions. These mechanisms may involve interactions between hormones and manure as well as preferential flow paths, leading to enhanced transport rates. These types of interactions should be further investigated to understand the processes regulating hormone transport in the subsurface environment and parametrized to forecast long-term fate and transport of steroidal hormones.
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Affiliation(s)
- Shai Arnon
- Department of Environmental Hydrology and Microbiology, Zuckerberg Institute for Water Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel
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22
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Ishida CK, Arnon S, Peterson CG, Kelly JJ, Gray KA. Influence of algal community structure on denitrification rates in periphyton cultivated on artificial substrata. Microb Ecol 2008; 56:140-152. [PMID: 17965949 DOI: 10.1007/s00248-007-9332-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Accepted: 10/02/2007] [Indexed: 05/25/2023]
Abstract
We conducted a field survey of periphyton cultivated on benthic mesh installations in freshwater aquatic systems, including two constructed wetlands and a pond, and also studied periphyton grown on a benthic mesh in laboratory mesocosms. The objectives of this study were to (1) determine if periphyton cultivated on benthic mesh denitrifies at higher rates than the underlying sediments and (2) determine if denitrification rates within periphyton vary with characteristics such as algal and bacterial community structure and biomass. We measured denitrification potential rates of field and laboratory periphyton by the acetylene inhibition method. We characterized algal community composition by algal identification and bacterial community composition by terminal restriction fragment length polymorphisms. Periphyton collected on benthic mesh from our field sites denitrified at significantly higher rates than the underlying sediments, regardless of sampling site or season. Results from both our field survey and laboratory studies indicated a significant, positive correlation between diatom presence and denitrification rate. In our laboratory studies, we found that periphyton with the highest diatom abundance showed the highest denitrification rates as well as a distinct bacterial community composition. These results suggest a synergistic relationship between diatoms and denitrifying bacteria that warrants further study.
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Affiliation(s)
- Cari K Ishida
- Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL 60208-3109, USA
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Aviram R, Kidron D, Silverstein S, Lerer I, Abeliovich D, Tepper R, Dolfin Z, Markovitch O, Arnon S. Placental mesenchymal dysplasia associated with transient neonatal diabetes mellitus and paternal UPD6. Placenta 2008; 29:646-9. [PMID: 18486206 DOI: 10.1016/j.placenta.2008.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Revised: 04/07/2008] [Accepted: 04/09/2008] [Indexed: 10/22/2022]
Affiliation(s)
- R Aviram
- Ultrasound Unit, Department of Obstetrics and Gynecology, Meir Hospital, 59 Tchernihovski Street, Kfar Sava, Israel.
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Arnon S, Peterson CG, Gray KA, Packman AI. Influence of flow conditions and system geometry on nitrate use by benthic biofilms: implications for nutrient mitigation. Environ Sci Technol 2007; 41:8142-8148. [PMID: 18186350 DOI: 10.1021/es0710048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The effects of substratum geometry and overlying velocity on nitrate use by periphyton were assessed. Periphyton was cultivated at an average current velocity of 0.5 cm s(-1) in laboratory mesocosms (120 cm long, 60 cm wide) on polyethylene nets of three different geometries, "1-lay er", "3-layer", and "bedform" structures, overlaying a thin bed of sand. Bulk nitrate use was then measured as the reduction of nitrate concentration in the overlying water under average velocities of 0.005, 0.05, and 0.5 cm s(-1). Periphyton structural characteristics were quantified as algal/bacterial biomass, algal species composition, and bacterial densities. Accrual of microbial biomass increased monotonically with increasing benthic net surface area, with upper sections of structures supporting the highest biomass. Maximum rates of nitrate removal were measured in the bedform geometry at intermediate velocity (173 mg NO3-N m(-2) d(-1)), and the lowest was measured with 1-layer geometry at the fastest velocity (11 mg NO3-N m(-2) d(-1)). Oxygen microprofiles within biofilms demonstrated that hydrodynamic conditions and benthic structure both play a key role in the regulation of microbial processing of nitrate delivered from the water column by promotion of denitrification in downstream sections of bedform substrata. Interactions between hydrodynamic conditions and substratum geometry are expected to regulate microbial activity in all surficial natural and engineered environments and must be parameterized to forecast long-term average biochemical transformation rates in rivers and other dynamic aquatic systems.
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Affiliation(s)
- Shai Arnon
- Department of Civil and Environmental Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
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Saada A, Shaag A, Arnon S, Dolfin T, Miller C, Fuchs-Telem D, Lombes A, Elpeleg O. Antenatal mitochondrial disease caused by mitochondrial ribosomal protein (MRPS22) mutation. J Med Genet 2007; 44:784-6. [PMID: 17873122 PMCID: PMC2652816 DOI: 10.1136/jmg.2007.053116] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Three patients born to the same set of consanguineous parents presented with antenatal skin oedema, hypotonia, cardiomyopathy and tubulopathy. The enzymatic activities of multiple mitochondrial respiratory chain complexes were reduced in muscle. Marked reduction of 12s rRNA, the core of the mitochondrial small ribosomal subunit, was found in fibroblasts. Homozygosity mapping led to the identification of a mutation in the MRPS22 gene, which encodes a mitochondrial ribosomal protein. Transfection of the patient cells with wild-type MRPS22 cDNA increased the 12s rRNA content and normalised the enzymatic activities. Quantification of mitochondrial transcripts is advisable in patients with multiple defects of the mitochondrial respiratory chain.
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Affiliation(s)
- A Saada
- Metabolic Disease Unit, Hadassah - Hebrew University Medical Center, Jerusalem, 91120, Israel
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Abstract
OBJECTIVES To evaluate the accuracy of serum amyloid A (SAA), an acute phase protein in the detection of neonatal early-onset sepsis, by means of a fast automated SAA kit. STUDY DESIGN Full-term infants <72 h of age, who had risk factors and/or were suspected of having sepsis, were eligible for study. The levels of SAA were taken at 0, 24 and 48 h post sepsis evaluation. Thirty matched infants served as a control group for comparing SAA concentrations. RESULTS Of 104 infants eligible for entry to the study, 23 had sepsis and 81 had not sepsis. The SAA levels of the septic group were significantly higher than those of the nonseptic group at 0, 24 and 48 h (P<0.01 for all time points). In comparison with C-reactive protein (CRP), SAA levels rose earlier and in a sharper manner, had higher levels and returned faster to normal values in infants with early onset sepsis. At 0 h post-sepsis evaluation, serum SAA had an overall better diagnostic accuracy for predicting early onset sepsis than CRP (sensitivity (96 vs 30%), specificity (95 vs 98%), positive predictive value (85 vs 78%), negative predictive value (99 vs 83%), positive likelihood ratio (19 vs 12), and negative likelihood ratio (0.05 vs 0.71). CONCLUSIONS SSA is advocated as an inflammatory marker of neonatal early-onset sepsis.
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Affiliation(s)
- S Arnon
- Department of Neonatology, Meir Medical Center, Kfar-Saba, Israel.
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Litmanovitz I, Dolfin T, Arnon S, Regev RH, Nemet D, Eliakim A. Assisted exercise and bone strength in preterm infants. Calcif Tissue Int 2007; 80:39-43. [PMID: 17164971 DOI: 10.1007/s00223-006-0149-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2006] [Accepted: 08/12/2006] [Indexed: 11/24/2022]
Abstract
Studies have previously demonstrated that brief (4 weeks) passive range-of-motion exercise is beneficial for bone development in very low birth weight (VLBW) preterm infants. However, the optimal duration of exercise for bone development in preterm infants is yet unknown. The aim of the present study was to examine the effect of 8 weeks of assisted exercise on bone strength and metabolism in VLBW premature infants. Sixteen infants (mean +/- standard error of the mean birth weight 1,009 +/- 55 g and gestational age 27.3 +/- 0.3 weeks) were randomly assigned into exercise (n = 8) and control (n = 8) groups. The intervention started at the first week of life and involved 8 weeks of daily passive extension and flexion range-of-motion exercise of the upper and lower extremities. Biochemical markers of bone turnover were measured at enrollment and after 8 weeks. Bone strength was measured weekly by quantitative ultrasound measurement of tibial bone speed of sound (SOS). Bone SOS decreased significantly in the control group (-108.1 +/- 33.7 m/second, P < 0.0001) during the study period, while remaining stable in the exercise group (11.3 +/- 22.8 m/second). The main beneficial effect of exercise occurred in the first 4 weeks of the intervention. There were no significant differences in the bone turnover marker changes between the groups. There is a significant postnatal decrease in bone SOS in VLBW preterm infants. Eight weeks of assisted range-of-motion exercise attenuates the decrease in bone strength and may decrease the risk of osteopenia in premature infants.
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Affiliation(s)
- I Litmanovitz
- Department of Neonatology, Pediatrics, Meir Medical Center, Kfar-Saba, Sackler School of Medicine, Tel-Aviv University, 59 Tchernichovsky Street, Kfar-Saba 44281, Israel
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Arnon S, Ronen Z, Yakirevich A, Adar E. Evaluation of soil flushing potential for clean-up of desert soil contaminated by industrial wastewater. Chemosphere 2006; 62:17-25. [PMID: 15949835 DOI: 10.1016/j.chemosphere.2005.04.050] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 03/28/2005] [Accepted: 04/06/2005] [Indexed: 05/02/2023]
Abstract
The flushing potential of a desert loess soil contaminated by the flame retardant Tetrabromobisphenol A (TBBPA), chloride (Cl(-)) and bromide (Br(-)) was studied in undisturbed laboratory column experiments (20 cm diameter, 45 cm long) and a small field plot (2 x 2 m). While the soluble inorganic ions (Cl(-) and Br(-)) were efficiently flushed from the soil profile after less than three pore volumes (PV) of water, about 50% of the initial amount of TBBPA in the soil was also flushed, despite its hydrophobic nature. TBBPA leaching was made possible due to a significant increase in the pH of the soil solution from 7.5 to 9, which increased TBBPA aqueous solubility. The remaining TBBPA mass in the soil was not mobilized from its initial location in the topsoil due to the decrease in pH at this horizon. In situ soil flushing demonstrated that this method is a feasible treatment for reducing soil contamination at this site.
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Affiliation(s)
- Shai Arnon
- Department of Environmental Hydrology and Microbiology, Zuckerberg Institute for Water Research, J. Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus 84990, Israel.
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30
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Arnon S, Ronen Z, Adar E, Yakirevich A, Nativ R. Two-dimensional distribution of microbial activity and flow patterns within naturally fractured chalk. J Contam Hydrol 2005; 79:165-86. [PMID: 16099071 DOI: 10.1016/j.jconhyd.2005.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2004] [Revised: 06/16/2005] [Accepted: 06/17/2005] [Indexed: 05/04/2023]
Abstract
The two-dimensional distribution of flow patterns and their dynamic change due to microbial activity were investigated in naturally fractured chalk cores. Long-term biodegradation experiments were conducted in two cores ( approximately 20 cm diameter, 31 and 44 cm long), intersected by a natural fracture. 2,4,6-tribromophenol (TBP) was used as a model contaminant and as the sole carbon source for aerobic microbial activity. The transmissivity of the fractures was continuously reduced due to biomass accumulation in the fracture concurrent with TBP biodegradation. From multi-tracer experiments conducted prior to and following the microbial activity, it was found that biomass accumulation causes redistribution of the preferential flow channels. Zones of slow flow near the fracture inlet were clogged, thus further diverting the flow through zones of fast flow, which were also partially clogged. Quantitative evaluation of biodegradation and bacterial counts supported the results of the multi-tracer tests, indicating that most of the bacterial activity occurs close to the inlet. The changing flow patterns, which control the nutrient supply, resulted in variations in the concentrations of the chemical constituents (TBP, bromide and oxygen), used as indicators of biodegradation.
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Affiliation(s)
- Shai Arnon
- Department of Environmental Hydrology and Microbiology, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus 84990, Israel.
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Arnon S, Adar E, Ronen Z, Nejidat A, Yakirevich A, Nativ R. Biodegradation of 2,4,6-tribromophenol during transport in fractured chalk. Environ Sci Technol 2005; 39:748-755. [PMID: 15757335 DOI: 10.1021/es0491578] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effect of physicochemical conditions (residence time, oxygen concentrations, and chalk characteristics) on the biodegradation of 2,4,6-tribromophenol (TBP) during transport was investigated in low-permeability fractured-chalk cores. Long-term (approximately 600 d) biodegradation experiments were conducted in two cores (approximately 21 cm diameter, 31 and 44 cm long, respectively), intersected by a natural fracture. TBP was used as a model contaminant and as the sole carbon source for aerobic microbial activity. Bacterial isolates were recovered and identified by both Biolog identification kit and 16S rDNA sequences from batch enrichment cultures. One of the strains, with 98% similarity (based on the 16S rDNA data) to Achromobacter xylosoxidans, was shown to have the ability to degrade TBP in the presence of chalk. The decrease in TBP concentration along the fracture due to biodegradation was not affected by reducing the residence time from 49 to 8 min. In contrast, adding oxygen to the water at the inlet and increasing the flow rates improved TBP removal. Although the matrix pore-size distribution limits microbial activity to the fracture void, the chalk appears to provide an excellent environment for biodegradation activity. Approximately 90% of TBP removal occurred within 10 cm of the TBP source, indicating that in-situ bioremediation can be used to remove organic contaminants in low-permeability fractured rocks if nutrient-delivery pathways within the aquifer are secured.
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Affiliation(s)
- Shai Arnon
- Department of Environmental Hydrology & Microbiology, Ben-Gurion University of the Negev, Sede-Boqer 84990, Israel.
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Arnon S, Adar E, Ronen Z, Yakirevich A, Nativ R. Impact of microbial activity on the hydraulic properties of fractured chalk. J Contam Hydrol 2005; 76:315-336. [PMID: 15683886 DOI: 10.1016/j.jconhyd.2004.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Revised: 11/15/2004] [Accepted: 11/26/2004] [Indexed: 05/24/2023]
Abstract
The impact of microbial activity on fractured chalk transmissivity was investigated on a laboratory scale. Long-term experiments were conducted on six fractured chalk cores (20 cm diameter, 23-44 cm long) containing a single natural fracture embedded in a porous matrix. Biodegradation experiments were conducted under various conditions, including several substrate and oxygen concentrations and flow rates. 2,4,6-Tribromophenol (TBP) was used as a model contaminant (substrate). TBP biodegradation efficiency depended mainly on the amount of oxygen. However, under constant oxygen concentration at the core inlet, elevating the flow rates increased the removal rate of TBP. Transmissivity reduction was clearly related to TBP removal rate, following an initial slow decline and a further sharp decrease with time. The fracture's transmissivity was reduced by as much as 97% relative to the initial value, with no leveling off of the clogging process. For the most extreme cases, reductions of 262 and 157 microm in the equivalent hydraulic apertures were recorded for fractures with initial apertures of 495 and 207 microm, respectively. The reductions in fracture transmissivity occurred primarily because of clogging by bacterial cells and extracellular polymeric substances (EPS) produced by the bacteria. Most of the biodegradation activity was concentrated near the fracture inlet, where the most suitable biodegradation conditions (nutrients and oxygen) prevailed, suggesting that the clogging had occurred in that vicinity. The clogging must have changed the structure of the fracture void, thereby reducing the active volume participating in flow and transport processes. This phenomenon caused accelerated transport of non-reactive tracers and doubled the fracture's dispersivity under constant flow rates.
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Affiliation(s)
- Shai Arnon
- Department of Environmental Hydrology & Microbiology, Zuckerberg Institute for Water Research, J. Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer 84990, Israel.
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Shinwell ES, Karplus M, Bader D, Dollberg S, Gur I, Weintraub Z, Arnon S, Gottfreid E, Zaritsky A, Makhoul IR, Reich D, Sirota L, Berger I, Kogan A, Yurman S, Goldberg M, Kohelet D. Neonatologists are using much less dexamethasone. Arch Dis Child Fetal Neonatal Ed 2003; 88:F432-3. [PMID: 12937052 PMCID: PMC1721606 DOI: 10.1136/fn.88.5.f432] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Two historical cohorts (1993-1994 and 2001) of preterm infants ventilated for respiratory distress syndrome were compared. Dexamethasone administration fell from 22% to 6%. Chronic lung disease in survivors rose slightly from 13% to 17%, and mortality fell from 21% to 15% (other causes). The effect of restriction of dexamethasone use on chronic lung disease and mortality remains to be seen.
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MESH Headings
- Birth Weight
- Cohort Studies
- Dexamethasone/therapeutic use
- Gestational Age
- Glucocorticoids/therapeutic use
- Humans
- Incidence
- Infant Mortality
- Infant, Newborn
- Infant, Premature, Diseases/drug therapy
- Infant, Premature, Diseases/mortality
- Infant, Premature, Diseases/therapy
- Israel/epidemiology
- Lung Diseases/chemically induced
- Respiration, Artificial/methods
- Respiratory Distress Syndrome, Newborn/drug therapy
- Respiratory Distress Syndrome, Newborn/mortality
- Respiratory Distress Syndrome, Newborn/therapy
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Affiliation(s)
- E S Shinwell
- Kaplan Medical Center, Rehovot, Israel. Soroka Medical Center, Beersheva, Israel.
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Reish O, Dolfin T, Arnon S, Regev R, Grinshpan G, Yamazaki M, Ozono K. Glu274Lys/Gly309Arg mutation of the tissue-nonspecific alkaline phosphatase gene in neonatal hypophosphatasia associated with convulsions. J Inherit Metab Dis 2002; 25:35-40. [PMID: 11999978 DOI: 10.1023/a:1015121414782] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We describe a patient diagnosed with lethal perinatal hypophosphatasia with a unique clinical presentation of convulsions that responded to vitamin B6. Genomic DNA sequence analysis of the tissue-nonspecific alkaline phosphatase (TNSALP) gene revealed two missense mutations: a G-to-A transition resulting in a Glu to Lys at codon 274 (E274K), and a G-to-C transversion resulting in a Gly to Arg at codon 309 (G309R). The first mutation was maternally transmitted and was previously characterized as a moderate one, whereas the latter was paternally transmitted and has not been previously reported. Phenotype/genotype correlation indicates that G309R is a deleterious mutation that can lead to seizures and a lethal outcome, as was demonstrated in our patient.
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Abstract
Currently, preterm labour is treated with tocolytic agents and prenatal steroids until the 34th week of gestation only. Our objective in this study was to assess this practice. Seven-year records of all preterm infants born in our institution at 34--36 weeks of gestation, were evaluated retrospectively. All babies, born in singleton well-dated pregnancies, without maternal, medical or obstetric complications, and by normal vaginal delivery, were included. Their length of hospital stay and perinatal complications were compared across gestational age groups of 34, 35 and 36 weeks. Of the 207 babies included, statistically significant reductions in the rates of respiratory distress syndrome (15.0% vs. 3.2%), nosocomial sepsis (5.0% vs. 0%) and apnoea of prematurity (11.7% vs. 2.2%), and consequently, in length of hospital stay (16 +/- 2.7 vs. 4 +/- 0.3 days) occurred between 34 and 36 weeks of gestation. The severity of respiratory distress syndrome also declined significantly. The changes were most noticeable after 35 weeks of gestation, and it was concluded that neonatal complications are still prevalent at 34 and 35 weeks. Therefore, we propose that labour should not be induced at 34 and 35 weeks of gestation and that tocolytic agents and maternal prenatal steroids may be considered in preterm labour during this period.
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Affiliation(s)
- S Arnon
- Department of Neonatology, Meir Hospital, Sapir Medical Center, Kfar-Saba, Israel.
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36
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Abstract
We determined the levels of circulating bone turnover markers in preterm infants during the first weeks of life. Twenty premature infants (mean gestational age 27+/-2.2 weeks, mean birth weight 894+/-231 g) hospitalized in the neonatal intensive care unit (NICU) at the Meir General Hospital, Israel, participated in the study. Measurements of bone turnover markers were performed at birth, and every week thereafter for an average follow-up of 11.2+/-0.7 weeks. Bone osteoblastic activity was assessed by measurements of circulating osteocalcin, bone-specific alkaline phosphatase (BSAP) and the C-terminal procollagen peptide (PICP) levels. Bone resorption was assessed by measurements of serum levels of the carboxy-terminal cross-links telopeptide of type I collagen (ICTP). All three markers of osteoblastic activity increased markedly and significantly during the first three weeks of life, and then continued to increase gradually until week 10 (p<0.01). Circulating ICTP levels increased in the first week of life and then decreased gradually throughout the follow-up (p<0.01). The study participants were divided into premature infants born at extremely low birth weight (ELBW: <1000 g, n=12) and very low birth weight (VLBW: 1000-1250 g, n=8). Osteocalcin (in weeks 2-5 of life), PICP (weeks 3-5), and ICTP levels (weeks 2-3) were significantly higher in VLBW preterms. These results suggest increased bone formation in premature infants in the first three months of life. The increased bone turnover in VLBW compared to ELBW premature infants may be the result of a generally higher morbidity in ELBW preterm infants in early stages of life.
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Affiliation(s)
- Y Shiff
- Neonatal Intensive Care Unit, Meir General Hospital, Kfar Saba, Israel
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37
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Abstract
We describe a preterm neonate with documented group B Streptococcus sepsis and associated metabolic acidosis whose lactic acidemia was refractory to conventional sodium bicarbonate therapy but responded well to dichloroacetate treatment.
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Affiliation(s)
- S Arnon
- Department of Pediatrics, Meir General Hospital, Kfar-Saba, Israel.
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Abstract
Reported herein are the cases of three infants who were born with serious intrathoracic injuries, apparently sustained at the time of the mother's involvement in a motor vehicle accident. The accidents occurred at 26th, 29th and 36th weeks of pregnancy and resulted in minimal injuries to the mothers themselves. The infants were born four weeks, three hours and two days later, respectively. Their injuries were manifested (singly) by hemothorax, pneumothorax and contusion of lung, the latter in a setting of multi-organ trauma. We suggest that chest x-ray, in addition to brain ultrasound, be routinely included in the evaluation of neonates whose mothers were involved in a motor vehicle accident during pregnancy, not excluding cases wherein the mother's injuries were negligible or inapparent and regardless of the time elapsed between accident and delivery.
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Affiliation(s)
- I Litmanovitz
- Department of Neonatology, Meir General Hospital, Kfar Saba, Israel.
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39
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Affiliation(s)
- R H Regev
- Neonatal Department, Meir Hospital, Sapir Medical Center, Kfar Saba, Israel.
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40
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Abstract
UNLABELLED Children with adrenocortical insufficiency are commonly instructed to increase three to five times baseline glucocorticoid replacement dose during periods of stress such as surgery or febrile illness. The present study was undertaken to determine whether these recommendations reflect the actual change in urinary free cortisol (UFC) output during stress in neonates and to test the effect of stress on the diurnal variation of cortisol in this age group. DESIGN AND PATIENTS Twenty-four hour urinary free cortisol (UFC) excretion was determined in 75 neonates during the first 2 days of life. Thirty were healthy and 45 were neonates with respiratory distress. In 60 babies the 24-h UFC was collected in 6-h fractions for the determination of diurnal variation of urinary cortisol. RESULTS The mean change in UFC was 4.5 times higher in the sick babies than in the controls. A distinct diurnal variation of UFC was noted in both healthy and sick babies. CONCLUSIONS In contrast with previous publications a distinct diurnal pattern was noted in the majority of neonates.
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Affiliation(s)
- Z Zadik
- Pediatric Endocrine Unit, Kaplan Medical Center, Rehovot, Israel
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41
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Abstract
Perinatal hemochromatosis is a rare disorder with an enormous iron overload in the parenchymal organs, especially the liver, pancreas, heart and endocrine glands. Elements of the reticuloendothelial system are relatively spared. The clinical course is rapidly progressive and the disease is invariably fatal. Several siblings are described in the literature. Herein, we describe one pair of full siblings affected by the disease, wherein the clinical presentation was hydrops. We suggest that hemochromatosis should be considered in the differential diagnosis of hydrops fetalis.
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Affiliation(s)
- E Kassem
- Pediatric Department, Sapir Medical Center, Kfar Saba, Israel
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42
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Arnon S. Power versus stabilization for laser satellite communication. Appl Opt 1999; 38:3229-3233. [PMID: 18319913 DOI: 10.1364/ao.38.003229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
To establish optical communication between any two satellites, the lines of sight of their optics must be aligned for the duration of the communication. The satellite pointing and tracking systems perform the alignment. The satellite pointing systems vibrate because of tracking noise and mechanical impacts (such as thruster operation, the antenna pointing mechanism, the solar array driver, navigation noise, tracking noise). These vibrations increase the bit error rate (BER) of the communication system. An expression is derived for adaptive transmitter power that compensates for vibration effects in heterodyne laser satellite links. This compensation makes it possible to keep the link BER performance constant for changes in vibration amplitudes. The motivation for constant BER is derived from the requirement for future satellite communication networks with high quality of service. A practical situation of a two-low-Earth-orbit satellite communication link is given. From the results of the example it is seen that the required power for a given BER increases almost exponentially for linear increase in vibration amplitude.
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Affiliation(s)
- S Arnon
- Department of Electrical and Computer Engineering, Ben Gurion University of the Negev, Post Office Box 653, Beer Sheva 84105, Israel.
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43
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Arnon S, Rotman SR, Kopeika NS. Performance limitations of a free-space optical communication satellite network owing to vibrations: heterodyne detection. Appl Opt 1998; 37:6366-6374. [PMID: 18286137 DOI: 10.1364/ao.37.006366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Free-space optical communication between satellites in a distributed network can permit high data rates of communication between different places on Earth. To establish optical communication between any two satellites requires that the line of sight of their optics be aligned during the entire communication time. Because of the large distance between the satellites and the alignment accuracy required, the pointing from one satellite to another is complicated because of vibrations of the pointing system caused by two fundamental stochastic mechanisms: tracking noise created by the electro-optic tracker and vibrations derived from mechanical components. Vibration of the transmitter beam in the receiver plane causes a decrease in the received optical power. Vibrations of the receiver telescope relative to the received beam decrease the heterodyne mixing efficiency. These two factors increase the bit-error rate of a coherent detection network. We derive simple mathematical models of the network bit-error rate versus the system parameters and the transmitter and receiver vibration statistics. An example of a practical optical heterodyne free-space satellite optical communication network is presented. From this research it is clear that even low-amplitude vibration of the satellite-pointing systems dramatically decreases network performance.
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44
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Arnon S. Use of satellite natural vibrations to improve performance of free-space satellite laser communication. Appl Opt 1998; 37:5031-5036. [PMID: 18285973 DOI: 10.1364/ao.37.005031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In some of the future laser communication satellites, it is plausible to assume that tracking and communication receivers will use the same detector array. The reason for dual use of the detector is to design simpler and less expensive satellites. Satellites vibrate continually because of their subsystems and environmental sources. The vibrations cause nonuniform spreading of the received energy on the detector array. In view of this, the information from the tracking system is used to adapt individually the communication signal gain of each of the detectors in the array. This adaptation of the gains improves communication system performance. It is important to emphasize that the communication performance improvement is achieved only by gain adaptation. Any additional vibrations decrease the tracking and laser pointing system performances, which decrease the return communication performances (two-way communication). A comparison of practical communication systems is presented. The novelty of this research is the utilization of natural satellite vibrations to improve the communication system performance.
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45
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Arnon S, Rotman S, Kopeika NS. Beam width and transmitter power adaptive to tracking system performance for free-space optical communication. Appl Opt 1997; 36:6095-6101. [PMID: 18259455 DOI: 10.1364/ao.36.006095] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The basic free-space optical communication system includes at least two satellites. To communicate between them, the transmitter satellite must track the beacon of the receiver satellite and point the information optical beam in its direction. Optical tracking and pointing systems for free space suffer during tracking from high-amplitude vibration because of background radiation from interstellar objects such as the Sun, Moon, Earth, and stars in the tracking field of view or the mechanical impact from satellite internal and external sources. The vibrations of beam pointing increase the bit error rate and jam communication between the two satellites. One way to overcome this problem is to increase the satellite receiver beacon power. However, this solution requires increased power consumption and weight, both of which are disadvantageous in satellite development. Considering these facts, we derive a mathematical model of a communication system that adapts optimally the transmitter beam width and the transmitted power to the tracking system performance. Based on this model, we investigate the performance of a communication system with discrete element optical phased array transmitter telescope gain. An example for a practical communication system between a Low Earth Orbit Satellite and a Geostationary Earth Orbit Satellite is presented. From the results of this research it can be seen that a four-element adaptive transmitter telescope is sufficient to compensate for vibration amplitude doubling. The benefits of the proposed model are less required transmitter power and improved communication system performance.
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46
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Arnon S, Kopeika NS. Adaptive optical transmitter and receiver for space communication through thin clouds. Appl Opt 1997; 36:1987-1993. [PMID: 18250889 DOI: 10.1364/ao.36.001987] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Optical space communication from satellite to ground or air to air consists of clouds as part of communication channels. Propagation of optical pulses through clouds causes widening and deformation in the time domain and attenuation of the pulse radiant power. These effects decrease the received signal and limit the information bandwidth of the communication system. Having dealt with the other effects previously, here we concentrate on pulse broadening in the time domain. We derive a mathematical model of an adaptive optical communication system with a multiscattering channel (atmospheric cloud). We use knowledge about the impulse response function of the cloud to adapt the communication parameters to the transfer function of the cloud. The communication system includes a receiver and a transmitter. We adapted the transmitter to atmospheric conditions by changing the bit error rate. One can adapt the receiver to the atmospheric condition by changing the parameters of the detector and the filter. An example for a practical communication system between a low Earth orbit satellite and a ground station cover by cloud is given. Comparison and analysis of an adaptive and semiadaptive system with cloud channels are presented. Our conclusion is that in some cases only by such adaptive methods is optical communication possible.
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47
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Arnon S, Kopeika NS. Probing and monitoring aerosol and atmospheric clouds with an electro-optic oscillator. Appl Opt 1996; 35:5427-5434. [PMID: 21127541 DOI: 10.1364/ao.35.005427] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Monitoring, probing, and sensing characteristics of aerosol clouds is difficult and complicated. Probing the characteristics of aerosols is most useful in the chemical and microelectronic industry for processing control of aerosols and emulsion, decreasing bit error rate in adaptive optical communication systems, and in acquiring data for atmospheric science and environment quality. We present a new mathematical and optical engineering model for monitoring characteristics of aerosol clouds. The model includes the temporal transfer function of aerosol clouds as a variable parameter in an electro-optic oscillator. The frequency of the oscillator changes according to changes in the characteristics of the clouds (density, size distribution, physical thickness, the medium and the particulate refractive indices, and spatial distribution). It is possible to measure only one free characteristic at a given time. An example of a practical system for monitoring the density of aerosol clouds is given. The frequency of the oscillator changes from 1.25 to 0.43 MHz for changes in aerosol density from 2000 to 3000 particulates cm(-3). The advantages of this new method compared with the transmissometer methods are (a) no necessity for line-of-sight measurement geometry, (b) accurate measurement of high optical thickness media is possible, (c) under certain conditions measurements can include characteristics of aerosol clouds related to light scatter that cannot be or are difficult to measure with a transmissometer, and (d) the cloud bandwidth for free space optical communication is directly measurable.
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48
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Abstract
The aim of this randomized, double-blind, placebo-controlled trial was to assess the short-term effect of a topical glucocorticoid (budesonide 600 mu g twice daily) vs. placebo administered by metered dose inhaler (MDL) and spacer (Aerochamber MV15) directly into endotracheal tube of intubated infants for 7 days. Twenty preterm infants (mean birthweight, 1,030 g; mean gestational age, 27.3 weeks)who still needed assisted ventilation at 14 days of age were randomly assigned to receive budesonide (n=9) or placebo (n=11) and completed the study. The primary outcome was the need for mechanical ventilation after 7 days of treatment. Other outcome variables included ventilator settings, blood gases, serum cortisol levels, and bronchoalveolar lavage inflammatory cell counts. No ventilated infant was extubated during the study period. The treatment group showed significant improvements in mean peak inspiratory pressure, ventilator efficiency index, and (A-a) oxygen difference. There were no changes in the placebo group. Serum cortisol levels and bronchoalveolar lavage cell counts did not change significantly during study period. There was no difference in side effects between the groups. This trial demonstrates that topical budesonide administered by MDL and Aerochamber produces clinical improvement in ventilated preterm infants, without glucocorticoid side effects.
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Affiliation(s)
- S Arnon
- Department of Paediatrics and Neonatal Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom
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49
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Barak Y, Arnon S, Wolach B, Raz Y, Ashkenasi A, Glick B, Shapira Y. MELAS syndrome: peripheral neuropathy and cytochrome C-oxidase deficiency: a case report and review of the literature. Isr J Med Sci 1995; 31:224-229. [PMID: 7721560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A 4-year-old boy presented with developmental delay, aggressive behavior, and incoordination. His EEG showed a diffuse encephalopathy. At age 10 he developed convulsions and severe migraine-like headaches. Muscle wasting, arreflexia, and lactic acidemia following exercise were noted. Electromyography was myopathic and nerve conduction studies revealed a peripheral neuropathy. Muscle biopsy demonstrated variation in fiber size and an excess of lipid droplets. He than had several stroke-like episodes and periods of unconsciousness, associated with severe metabolic acidosis. Muscle cytochrome C oxidase was abnormally low. This boy displayed the classical clinical and biochemical features of MELAS syndrome, namely Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes. Treatment included carnitine, vitamin C, vitamin K, riboflavin, coenzyme Q10, and corticosteroids. He died at the age of 14 years following an episode of seizures, coma, and gastrointestinal hemorrhage. This is the first reported case of MELAS syndrome in Israel.
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Affiliation(s)
- Y Barak
- Department of Pediatrics, Meir General Hospital, Kfar Saba, Israel
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50
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Abstract
To evaluate the clinical significance of eosinophilia in newborn infants, 261 admissions to the neonatal unit over a 12-month period were studied retrospectively; 33 babies with eosinophilia (> 1.0 x 10(9)/l) were studied. Clinical and laboratory data for the first month of life were compared, where available, between gestational age-matched pairs with and without eosinophilia. Of the 33 babies with eosinophilia, 23 were > 26 weeks' gestation and all had age-matched controls; 10 were < or = 26 weeks' gestation but had no appropriate gestational age-matched controls. Babies > 26 weeks' gestation with eosinophilia had a significantly higher number of septic episodes than controls: 20 of 23 versus 4 of 23. All 10 babies < or = 26 weeks' gestation with eosinophilia developed sepsis. Infections with gram-negative organisms and necrotizing enterocolitis occurred only in babies who developed eosinophilia. In 5 babies no cause for the eosinophilia was found. In conclusion, eosinophilia in the newborn is usually explainable and is most often associated with infection.
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Affiliation(s)
- L Patel
- Department of Neonatal Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK
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