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Bruna EM, Uriarte M, Darrigo MR, Rubim P, Jurinitz CF, Scott ER, Ferreira da Silva O, Kress WJ. Demography of the understory herb Heliconia acuminata (Heliconiaceae) in an experimentally fragmented tropical landscape. Ecology 2023; 104:e4174. [PMID: 37776233 DOI: 10.1002/ecy.4174] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 06/16/2023] [Accepted: 07/17/2023] [Indexed: 10/02/2023]
Abstract
Habitat fragmentation remains a major focus of research by ecologists decades after being put forward as a threat to the integrity of ecosystems. While studies have documented myriad biotic changes in fragmented landscapes, including the local extinction of species from fragments, the demographic mechanisms underlying these extinctions are rarely known. However, many of them-especially in lowland tropical forests-are thought to be driven by one of two mechanisms: (1) reduced recruitment in fragments resulting from changes in the diversity or abundance of pollinators and seed dispersers or (2) increased rates of individual mortality in fragments due to dramatically altered abiotic conditions, especially near fragment edges. Unfortunately, there have been few tests of these potential mechanisms due to the paucity of long-term and comprehensive demographic data collected in both forest fragments and continuous forest sites. Here we report 11 years (1998-2009) of demographic data from populations of the Amazonian understory herb Heliconia acuminata (LC Rich.) found at Brazil's Biological Dynamics of Forest Fragments Project (BDFFP). The data set comprises >66,000 plant × year records of 8586 plants, including 3464 seedlings established after the first census. Seven populations were in experimentally isolated fragments (one in each of four 1-ha fragments and one in each of three 10-ha fragments), with the remaining six populations in continuous forest. Each population was in a 50 × 100 m permanent plot, with the distance between plots ranging from 500 m to 60 km. The plants in each plot were censused annually, at which time we recorded, identified, marked, and measured new seedlings, identified any previously marked plants that died, and recorded the size of surviving individuals. Each plot was also surveyed four to five times during the flowering season to identify reproductive plants and record the number of inflorescences each produced. These data have been used to investigate topics ranging from the way fragmentation-related reductions in germination influence population dynamics to statistical methods for analyzing reproductive rates. This breadth of prior use reflects the value of these data to future researchers. In addition to analyses of plant responses to habitat fragmentation, these data can be used to address fundamental questions in plant demography and the evolutionary ecology of tropical plants and to develop and test demographic models and tools. Though we welcome opportunities to collaborate with interested users, there are no restrictions on the use of this data set. However, we do request that those using the data for teaching or research purposes inform us of how they are doing so and cite this paper and the data archive when appropriate. Any publication using the data must also include a BDFFP Technical Series Number in the Acknowledgments. Authors can request this series number upon the acceptance of their article by contacting the BDFFP's Scientific Coordinator or E. M. Bruna.
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Affiliation(s)
- Emilio M Bruna
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, Florida, USA
- Center for Latin American Studies, University of Florida, Gainesville, Florida, USA
- Biological Dynamics of Forest Fragments Project, INPA-PDBFF, Manaus, Brazil
| | - María Uriarte
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, New York, USA
| | - Maria Rosa Darrigo
- Biological Dynamics of Forest Fragments Project, INPA-PDBFF, Manaus, Brazil
| | - Paulo Rubim
- Biological Dynamics of Forest Fragments Project, INPA-PDBFF, Manaus, Brazil
| | | | - Eric R Scott
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, Florida, USA
| | | | - W John Kress
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
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Richardson KM, Jospe MR, Saleh AA, Clarke TN, Bedoya AR, Behrens N, Marano K, Cigan L, Liao Y, Scott ER, Guo JS, Aguinaga A, Schembre SM. Use of Biological Feedback as a Health Behavior Change Technique in Adults: Scoping Review. J Med Internet Res 2023; 25:e44359. [PMID: 37747766 PMCID: PMC10562972 DOI: 10.2196/44359] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 07/26/2023] [Accepted: 08/03/2023] [Indexed: 09/26/2023] Open
Abstract
BACKGROUND Recent advancements in personal biosensing technology support the shift from standardized to personalized health interventions, whereby biological data are used to motivate health behavior change. However, the implementation of interventions using biological feedback as a behavior change technique has not been comprehensively explored. OBJECTIVE The purpose of this review was to (1) map the domains of research where biological feedback has been used as a behavior change technique and (2) describe how it is implemented in behavior change interventions for adults. METHODS A comprehensive systematic search strategy was used to query 5 electronic databases (Ovid MEDLINE, Elsevier Embase, Cochrane Central Register of Controlled Trials, EBSCOhost PsycINFO, and ProQuest Dissertations & Theses Global) in June 2021. Eligible studies were primary analyses of randomized controlled trials (RCTs) in adults that incorporated biological feedback as a behavior change technique. DistillerSR was used to manage the literature search and review. RESULTS After removing 49,500 duplicates, 50,287 articles were screened and 767 articles were included. The earliest RCT was published in 1972 with a notable increase in publications after 2000. Biological feedback was most used in RCTs aimed at preventing or managing diabetes (n=233, 30.4%), cardiovascular disease (n=175, 22.8%), and obesity (n=115, 15%). Feedback was often given on multiple biomarkers and targeted multiple health behaviors. The most common biomarkers used were anthropometric measures (n=297, 38.7%), blood pressure (n=238, 31%), and glucose (n=227, 29.6%). The most targeted behaviors were diet (n=472, 61.5%), physical activity (n=417, 54.4%), and smoking reduction (n=154, 20.1%). The frequency and type of communication by which biological feedback was provided varied by the method of biomarker measurement. Of the 493 (64.3%) studies where participants self-measured their biomarker, 476 (96.6%) received feedback multiple times over the intervention and 468 (94.9%) received feedback through a biosensing device. CONCLUSIONS Biological feedback is increasingly being used to motivate behavior change, particularly where relevant biomarkers can be readily assessed. Yet, the methods by which biological feedback is operationalized in intervention research varied, and its effectiveness remains unclear. This scoping review serves as the foundation for developing a guiding framework for effectively implementing biological feedback as a behavior change technique. TRIAL REGISTRATION Open Science Framework Registries; https://doi.org/10.17605/OSF.IO/YP5WAd. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) RR2-10.2196/32579.
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Affiliation(s)
- Kelli M Richardson
- School of Nutritional Sciences and Wellness, College of Agriculture, Life and Environmental Sciences, University of Arizona, Tucson, AZ, United States
| | - Michelle R Jospe
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, United States
| | - Ahlam A Saleh
- Arizona Health Sciences Library, University of Arizona, Tucson, AZ, United States
| | - Thanatcha Nadia Clarke
- Department of Physiology, College of Medicine, University of Arizona, Tucson, AZ, United States
| | - Arianna R Bedoya
- Department of Internal Medicine, College of Medicine - Phoenix, University of Arizona, Tucson, AZ, United States
| | - Nick Behrens
- Department of Ecology and Evolutionary Biology, College of Science, University of Arizona, Tucson, AZ, United States
| | - Kari Marano
- College of Nursing, University of Arizona, Tucson, AZ, United States
| | - Lacey Cigan
- School of Nutritional Sciences and Wellness, College of Agriculture, Life and Environmental Sciences, University of Arizona, Tucson, AZ, United States
| | - Yue Liao
- Department of Kinesiology, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington, TX, United States
| | - Eric R Scott
- Communications & Cyber Technologies, Arizona Experiment Station, University of Arizona, Tucson, AZ, United States
| | - Jessica S Guo
- Communications & Cyber Technologies, Arizona Experiment Station, University of Arizona, Tucson, AZ, United States
| | - April Aguinaga
- Arizona Health Sciences Library, University of Arizona, Tucson, AZ, United States
| | - Susan M Schembre
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, United States
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Goodman WR, Scott ER, Keith Z, Singh L, Anderson DT. Upgrade of the helically symmetric experiment Thomson scattering diagnostic suite. Rev Sci Instrum 2022; 93:093518. [PMID: 36182445 DOI: 10.1063/5.0101879] [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] [Received: 06/03/2022] [Accepted: 08/17/2022] [Indexed: 06/16/2023]
Abstract
The Helically Symmetric eXperiment (HSX) Thomson Scattering (TS) diagnostic is being upgraded to decrease uncertainty in electron temperature and density measurements. Upgrades to the HSX TS diagnostic will consist of a novel redesign of polychromator electronics and digitization of the TS output signal. Here, we also present a study of the benefits of an additional spectral channel that will sample the red-shifted band of the scattered spectrum. To maximize system bandwidth (BW) and gain, while minimizing noise, the existing low-BW polychromator electronics on HSX will be replaced by high-BW, high gain circuitry designed in-house.
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Affiliation(s)
- W R Goodman
- HSX Plasma Laboratory, University of Wisconsin, Madison, Wisconsin 53703, USA
| | - E R Scott
- HSX Plasma Laboratory, University of Wisconsin, Madison, Wisconsin 53703, USA
| | - Z Keith
- HSX Plasma Laboratory, University of Wisconsin, Madison, Wisconsin 53703, USA
| | - L Singh
- HSX Plasma Laboratory, University of Wisconsin, Madison, Wisconsin 53703, USA
| | - D T Anderson
- HSX Plasma Laboratory, University of Wisconsin, Madison, Wisconsin 53703, USA
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4
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Scott ER, Uriarte M, Bruna EM. Delayed effects of climate on vital rates lead to demographic divergence in Amazonian forest fragments. Glob Chang Biol 2022; 28:463-479. [PMID: 34697872 DOI: 10.1111/gcb.15900] [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: 06/28/2021] [Revised: 09/08/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Deforestation often results in landscapes where remaining forest habitat is highly fragmented, with remnants of different sizes embedded in an often highly contrasting matrix. Local extinction of species from individual fragments is common, but the demographic mechanisms underlying these extinctions are poorly understood. It is often hypothesized that altered environmental conditions in fragments drive declines in reproduction, recruitment, or survivorship. The Amazon basin, in addition to experiencing continuing fragmentation, is experiencing climate change-related increases in the frequency and intensity of droughts and unusually wet periods. Whether plant populations in tropical forest fragments are particularly susceptible to extremes in precipitation remains unclear. Most studies of plants in fragments are relatively short (1-6 years), focus on a single life-history stage, and often do not compare to populations in continuous forest. Even fewer studies consider delayed effects of climate on demographic vital rates despite the importance of delayed effects in studies that consider them. Using a decade of demographic and climate data from an experimentally fragmented landscape in the Central Amazon, we assess the effects of climate on populations of an understory herb (Heliconia acuminata, Heliconiaceae). We used distributed lag nonlinear models to understand the delayed effects of climate (measured as standardized precipitation evapotranspiration index, SPEI) on survival, growth, and flowering. We detected delayed effects of climate up to 36 months. Extremes in SPEI in the previous year reduced survival, drought in the wet season 8-11 months prior to the February census increased growth, and drought two dry seasons prior increased flowering probability. Effects of extremes in precipitation on survival and growth were more pronounced in forest fragments compared to continuous forest. The complex delayed effects of climate and habitat fragmentation in our study point to the importance of long-term demography experiments in understanding the effects of anthropogenic change on plant populations.
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Affiliation(s)
- Eric R Scott
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, Florida, USA
| | - María Uriarte
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, New York, USA
| | - Emilio M Bruna
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, Florida, USA
- Center for Latin American Studies, University of Florida, Gainesville, Florida, USA
- Biological Dynamics of Forest Fragments Project, INPA-PDBFF, Manaus, Amazonas, Brazil
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5
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Beidler CD, Smith HM, Alonso A, Andreeva T, Baldzuhn J, Beurskens MNA, Borchardt M, Bozhenkov SA, Brunner KJ, Damm H, Drevlak M, Ford OP, Fuchert G, Geiger J, Helander P, Hergenhahn U, Hirsch M, Höfel U, Kazakov YO, Kleiber R, Krychowiak M, Kwak S, Langenberg A, Laqua HP, Neuner U, Pablant NA, Pasch E, Pavone A, Pedersen TS, Rahbarnia K, Schilling J, Scott ER, Stange T, Svensson J, Thomsen H, Turkin Y, Warmer F, Wolf RC, Zhang D. Publisher Correction: Demonstration of reduced neoclassical energy transport in Wendelstein 7-X. Nature 2021; 598:E5. [PMID: 34642470 PMCID: PMC8550957 DOI: 10.1038/s41586-021-04023-y] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- C D Beidler
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany.
| | - H M Smith
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Alonso
- Laboratorio Nacional de Fusion, CIEMAT, Madrid, Spain
| | - T Andreeva
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Baldzuhn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | | | - M Borchardt
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S A Bozhenkov
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K J Brunner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Damm
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Drevlak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - O P Ford
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - G Fuchert
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Geiger
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - P Helander
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Hergenhahn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Germany
| | - M Hirsch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Höfel
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Ye O Kazakov
- Laboratory for Plasma Physics (LPP), École royale militaire/Koninklijke Militaire School (ERM/KMS), Brussels, Belgium
| | - R Kleiber
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Krychowiak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S Kwak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Langenberg
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H P Laqua
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Neuner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - N A Pablant
- Princeton Plasma Physics Laboratory, Princeton, NJ, USA
| | - E Pasch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Pavone
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T S Pedersen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K Rahbarnia
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Schilling
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - E R Scott
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T Stange
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Svensson
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Thomsen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Y Turkin
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - F Warmer
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - R C Wolf
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - D Zhang
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
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6
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Beidler CD, Smith HM, Alonso A, Andreeva T, Baldzuhn J, Beurskens MNA, Borchardt M, Bozhenkov SA, Brunner KJ, Damm H, Drevlak M, Ford OP, Fuchert G, Geiger J, Helander P, Hergenhahn U, Hirsch M, Höfel U, Kazakov YO, Kleiber R, Krychowiak M, Kwak S, Langenberg A, Laqua HP, Neuner U, Pablant NA, Pasch E, Pavone A, Pedersen TS, Rahbarnia K, Schilling J, Scott ER, Stange T, Svensson J, Thomsen H, Turkin Y, Warmer F, Wolf RC, Zhang D. Demonstration of reduced neoclassical energy transport in Wendelstein 7-X. Nature 2021; 596:221-226. [PMID: 34381232 PMCID: PMC8357633 DOI: 10.1038/s41586-021-03687-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 04/30/2020] [Accepted: 06/02/2021] [Indexed: 02/07/2023]
Abstract
Research on magnetic confinement of high-temperature plasmas has the ultimate goal of harnessing nuclear fusion for the production of electricity. Although the tokamak1 is the leading toroidal magnetic-confinement concept, it is not without shortcomings and the fusion community has therefore also pursued alternative concepts such as the stellarator. Unlike axisymmetric tokamaks, stellarators possess a three-dimensional (3D) magnetic field geometry. The availability of this additional dimension opens up an extensive configuration space for computational optimization of both the field geometry itself and the current-carrying coils that produce it. Such an optimization was undertaken in designing Wendelstein 7-X (W7-X)2, a large helical-axis advanced stellarator (HELIAS), which began operation in 2015 at Greifswald, Germany. A major drawback of 3D magnetic field geometry, however, is that it introduces a strong temperature dependence into the stellarator's non-turbulent 'neoclassical' energy transport. Indeed, such energy losses will become prohibitive in high-temperature reactor plasmas unless a strong reduction of the geometrical factor associated with this transport can be achieved; such a reduction was therefore a principal goal of the design of W7-X. In spite of the modest heating power currently available, W7-X has already been able to achieve high-temperature plasma conditions during its 2017 and 2018 experimental campaigns, producing record values of the fusion triple product for such stellarator plasmas3,4. The triple product of plasma density, ion temperature and energy confinement time is used in fusion research as a figure of merit, as it must attain a certain threshold value before net-energy-producing operation of a reactor becomes possible1,5. Here we demonstrate that such record values provide evidence for reduced neoclassical energy transport in W7-X, as the plasma profiles that produced these results could not have been obtained in stellarators lacking a comparably high level of neoclassical optimization.
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Affiliation(s)
- C D Beidler
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany.
| | - H M Smith
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Alonso
- Laboratorio Nacional de Fusion, CIEMAT, Madrid, Spain
| | - T Andreeva
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Baldzuhn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | | | - M Borchardt
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S A Bozhenkov
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K J Brunner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Damm
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Drevlak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - O P Ford
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - G Fuchert
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Geiger
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - P Helander
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Hergenhahn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Germany
| | - M Hirsch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Höfel
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Ye O Kazakov
- Laboratory for Plasma Physics (LPP), École royale militaire/Koninklijke Militaire School (ERM/KMS), Brussels, Belgium
| | - R Kleiber
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Krychowiak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S Kwak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Langenberg
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H P Laqua
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Neuner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - N A Pablant
- Princeton Plasma Physics Laboratory, Princeton, NJ, USA
| | - E Pasch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Pavone
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T S Pedersen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K Rahbarnia
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Schilling
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - E R Scott
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T Stange
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Svensson
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Thomsen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Y Turkin
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - F Warmer
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - R C Wolf
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - D Zhang
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
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7
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Ford OP, Vanó L, Alonso JA, Baldzuhn J, Beurskens MNA, Biedermann C, Bozhenkov SA, Fuchert G, Geiger B, Hartmann D, Jaspers RJE, Kappatou A, Langenberg A, Lazerson SA, McDermott RM, McNeely P, Neelis TWC, Pablant NA, Pasch E, Rust N, Schroeder R, Scott ER, Smith HM, Wegner T, Kunkel F, Wolf RC. Charge exchange recombination spectroscopy at Wendelstein 7-X. Rev Sci Instrum 2020; 91:023507. [PMID: 32113444 DOI: 10.1063/1.5132936] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/16/2020] [Indexed: 06/10/2023]
Abstract
The Charge Exchange Recombination Spectroscopy (CXRS) diagnostic has become a routine diagnostic on almost all major high temperature fusion experimental devices. For the optimized stellarator Wendelstein 7-X (W7-X), a highly flexible and extensive CXRS diagnostic has been built to provide high-resolution local measurements of several important plasma parameters using the recently commissioned neutral beam heating. This paper outlines the design specifics of the W7-X CXRS system and gives examples of the initial results obtained, including typical ion temperature profiles for several common heating scenarios, toroidal flow and radial electric field derived from velocity measurements, beam attenuation via beam emission spectra, and normalized impurity density profiles under some typical plasma conditions.
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Affiliation(s)
- O P Ford
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - L Vanó
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - J A Alonso
- CIEMAT, Avenida Complutense, 40, 28040 Madrid, Spain
| | - J Baldzuhn
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - M N A Beurskens
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - C Biedermann
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - S A Bozhenkov
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - G Fuchert
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - B Geiger
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - D Hartmann
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - R J E Jaspers
- Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands
| | - A Kappatou
- Max-Planck Institut für Plasmaphysik, 85748 Garching, Germany
| | - A Langenberg
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - S A Lazerson
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - R M McDermott
- Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands
| | - P McNeely
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - T W C Neelis
- Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands
| | - N A Pablant
- Princeton University Plasma Physics Laboratory, Princeton, New Jersey 08544, USA
| | - E Pasch
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - N Rust
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - R Schroeder
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - E R Scott
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - H M Smith
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - Th Wegner
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - F Kunkel
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - R C Wolf
- Max-Planck Institut für Plasmaphysik, 17491 Greifswald, Germany
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8
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Scott ER, Li X, Wei JP, Kfoury N, Morimoto J, Guo MM, Agyei A, Robbat A, Ahmed S, Cash SB, Griffin TS, Stepp JR, Han WY, Orians CM. Changes in Tea Plant Secondary Metabolite Profiles as a Function of Leafhopper Density and Damage. Front Plant Sci 2020; 11:636. [PMID: 32547579 PMCID: PMC7272924 DOI: 10.3389/fpls.2020.00636] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 04/24/2020] [Indexed: 05/12/2023]
Abstract
Insect herbivores have dramatic effects on the chemical composition of plants. Many of these induced metabolites contribute to the quality (e.g., flavor, human health benefits) of specialty crops such as the tea plant (Camellia sinensis). Induced chemical changes are often studied by comparing plants damaged and undamaged by herbivores. However, when herbivory is quantitative, the relationship between herbivore pressure and induction can be linearly or non-linearly density dependent or density independent, and induction may only occur after some threshold of herbivory. The shape of this relationship can vary among metabolites within plants. The tea green leafhopper (Empoasca onukii) can be a widespread pest on tea, but some tea farmers take advantage of leafhopper-induced metabolites in order to produce high-quality "bug-bitten" teas such as Eastern Beauty oolong. To understand the effects of increasing leafhopper density on tea metabolites important for quality, we conducted a manipulative experiment exposing tea plants to feeding by a range of E. onukii densities. After E. onukii feeding, we measured volatile and non-volatile metabolites, and quantified percent damaged leaf area from scanned leaf images. E. onukii density had a highly significant effect on volatile production, while the effect of leaf damage was only marginally significant. The volatiles most responsive to leafhopper density were mainly terpenes that increased in concentration monotonically with density, while the volatiles most responsive to leaf damage were primarily fatty acid derivatives and volatile phenylpropanoids/benzenoids. In contrast, damage (percent leaf area damaged), but not leafhopper density, significantly reduced total polyphenols, epigallocatechin gallate (EGCG), and theobromine concentrations in a dose-dependent manner. The shape of induced responses varied among metabolites with some changing linearly with herbivore pressure and some responding only after a threshold in herbivore pressure with a threshold around 0.6 insects/leaf being common. This study illustrates the importance of measuring a diversity of metabolites over a range of herbivory to fully understand the effects of herbivores on induced metabolites. Our study also shows that any increases in leafhopper density associated with climate warming, could have dramatic effects on secondary metabolites and tea quality.
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Affiliation(s)
- Eric R. Scott
- Department of Biology, Tufts University, Medford, MA, United States
- *Correspondence: Eric R. Scott, ;
| | - Xin Li
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Ji-Peng Wei
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Nicole Kfoury
- Department of Chemistry, Tufts University, Medford, MA, United States
| | - Joshua Morimoto
- Department of Chemistry, Tufts University, Medford, MA, United States
| | - Ming-Ming Guo
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Amma Agyei
- Department of Biology, Tufts University, Medford, MA, United States
| | - Albert Robbat
- Department of Chemistry, Tufts University, Medford, MA, United States
| | - Selena Ahmed
- Food and Health Lab, Department of Health and Human Development, Montana State University, Bozeman, MT, United States
| | - Sean B. Cash
- Friedman School of Nutrition and Policy, Tufts University, Medford, MA, United States
| | - Timothy S. Griffin
- Friedman School of Nutrition and Policy, Tufts University, Medford, MA, United States
| | - John R. Stepp
- Department of Anthropology, University of Florida, Gainsville, FL, United States
| | - Wen-Yan Han
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
- Wen-Yan Han,
| | - Colin M. Orians
- Department of Biology, Tufts University, Medford, MA, United States
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9
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Szöcs E, Stirling T, Scott ER, Scharmüller A, Schäfer RB. webchem: An R Package to Retrieve Chemical Information from the Web. J Stat Softw 2020. [DOI: 10.18637/jss.v093.i13] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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10
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Kfoury N, Scott ER, Orians CM, Ahmed S, Cash SB, Griffin T, Matyas C, Stepp JR, Han W, Xue D, Long C, Robbat A. Plant-Climate Interaction Effects: Changes in the Relative Distribution and Concentration of the Volatile Tea Leaf Metabolome in 2014-2016. Front Plant Sci 2019; 10:1518. [PMID: 31824541 PMCID: PMC6882950 DOI: 10.3389/fpls.2019.01518] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 10/31/2019] [Indexed: 06/08/2023]
Abstract
Climatic conditions affect the chemical composition of edible crops, which can impact flavor, nutrition and overall consumer preferences. To understand these effects, we sampled tea (Camellia sinensis (L.) Kuntze) grown in different environmental conditions. Using a target/nontarget data analysis approach, we detected 564 metabolites from tea grown at two elevations in spring and summer over 3 years in two major tea-producing areas of China. Principal component analysis and partial least squares-discriminant analysis show seasonal, elevational, and yearly differences in tea from Yunnan and Fujian provinces. Independent of location, higher concentrations of compounds with aromas characteristic of farmers' perceptions of high-quality tea were found in spring and high elevation teas. Yunnan teas were distinct from Fujian teas, but the effects of elevation and season were different for the two locations. Elevation was the largest source of metabolite variation in Yunnan yet had no effect in Fujian. In contrast seasonal differences were strong in both locations. Importantly, the year-to-year variation in chemistry at both locations emphasizes the importance of doing multi-year studies, and further highlights the challenge farmers face when trying to produce teas with specific flavor/health (metabolite) profiles.
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Affiliation(s)
- Nicole Kfoury
- Department of Chemistry, Tufts University, Medford, MA, United States
- Sensory and Science Center, Medford, MA, United States
| | - Eric R. Scott
- Department of Biology, Tufts University, Medford, MA, United States
| | - Colin M. Orians
- Sensory and Science Center, Medford, MA, United States
- Department of Biology, Tufts University, Medford, MA, United States
| | - Selena Ahmed
- Department of Health and Human Development, Montana State University, Bozeman, MT, United States
| | - Sean B. Cash
- Sensory and Science Center, Medford, MA, United States
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, United States
| | - Timothy Griffin
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, United States
| | - Corene Matyas
- Department of Geography, University of Florida, Gainesville, FL, United States
| | - John Richard Stepp
- Department of Anthropology, University of Florida, Gainesville, FL, United States
| | - Wenyan Han
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Dayuan Xue
- College of Life and Environmental Sciences, Minzu University of China, Beijing, China
| | - Chunlin Long
- College of Life and Environmental Sciences, Minzu University of China, Beijing, China
| | - Albert Robbat
- Department of Chemistry, Tufts University, Medford, MA, United States
- Sensory and Science Center, Medford, MA, United States
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11
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Orians CM, Schweiger R, Dukes JS, Scott ER, Müller C. Combined impacts of prolonged drought and warming on plant size and foliar chemistry. Ann Bot 2019; 124:41-52. [PMID: 30698658 PMCID: PMC6676383 DOI: 10.1093/aob/mcz004] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [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: 07/02/2018] [Accepted: 01/15/2019] [Indexed: 05/12/2023]
Abstract
BACKGROUND AND AIMS Future shifts in precipitation regimes and temperature are expected to affect plant traits dramatically. To date, many studies have explored the effects of acute stresses, but few have investigated the consequences of prolonged shifts in climatic conditions on plant growth and chemistry. METHODS Plant size and metabolite profiles were assessed on naturally occurring Plantago lanceolata plants growing under different precipitation (ambient, 50 % less than ambient = drought) and temperature (ambient, +0.8, +2.4 and +4.0 °C above ambient) treatments at the Boston Area Climate Experiment (constructed in 2007). KEY RESULTS The analysis of primary and secondary metabolites revealed pronounced effects of drought, and a precipitation × temperature interaction. Strikingly, the effects of precipitation were minimal at the two lower temperatures but marked at the two higher temperatures. Compared with the ambient condition, plants in the drought plots had lower concentrations of foliar nitrogen, amino acids and most sugars, and higher concentrations of sorbitol, citrate and malate, common stress-induced metabolites. This pattern was especially evident at high temperatures. Moreover, drought-exposed plants showed lower concentrations of catalpol, an iridoid glycoside. CONCLUSIONS While the effect of warming on the metabolite profiles was less pronounced, differences were marked when combined with drought. Given the interactive effect of environmental variables on leaf chemistry, and the fact that woody and herbaceous plants seem to differ in their responses to temperature and precipitation, future studies should account for the direct and indirect effects of the community response to multifactorial field conditions.
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Affiliation(s)
- Colin M Orians
- Department of Biology, Tufts University, Medford, MA, USA
| | - Rabea Schweiger
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | - Jeffrey S Dukes
- Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN, USA
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
- Department of Biology, University of Massachusetts Boston, Boston, MA, USA
| | - Eric R Scott
- Department of Biology, Tufts University, Medford, MA, USA
| | - Caroline Müller
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
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12
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Bozhenkov SA, Heym SJ, Beurskens MNA, Fuchert G, Pasch E, Scott ER, Wolf RC. On using Rayleigh scattering for in situ spectral calibration of Thomson scattering diagnostics. Rev Sci Instrum 2019; 90:033505. [PMID: 30927799 DOI: 10.1063/1.5072781] [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] [Received: 10/21/2018] [Accepted: 02/28/2019] [Indexed: 06/09/2023]
Abstract
A new method for in situ spectral calibration of Thomson scattering diagnostics is proposed. The idea of the method is to apply a wavelength tunable optical parametric oscillator for measurements of Rayleigh scattering at different wavelengths, from which relative sensitivities can be calculated. This extends the usual approach where Rayleigh scattering is used only at a single wavelength for the absolute calibration and spectral sensitivities are obtained separately. With the new approach, the full diagnostic setup is spectrally calibrated at once. Such a calibration can be repeated at regular intervals during an experimental campaign since it does not require a break of the vacuum. In this paper, the Rayleigh scattering calibration is tested in a laboratory setup with a sample Wendelstein 7-X (W7-X) polychromator. It is shown that relative sensitivities of spectral channels can be recovered with a sufficient resolution even under conditions of significant stray light. The stray light is overcome by measuring the linear dependence of the scattered signal on the gas pressure. Good results of laboratory tests motivate the installation of the new calibration system for the Thomson scattering diagnostic at W7-X.
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Affiliation(s)
- S A Bozhenkov
- Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald, Germany
| | - S J Heym
- Faculty of Mathematics and Natural Sciences, Technical University of Berlin, Hardenbergstrasse 36, D-10623 Berlin, Germany
| | - M N A Beurskens
- Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald, Germany
| | - G Fuchert
- Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald, Germany
| | - E Pasch
- Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald, Germany
| | - E R Scott
- Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald, Germany
| | - R C Wolf
- Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald, Germany
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13
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Kfoury N, Morimoto J, Kern A, Scott ER, Orians CM, Ahmed S, Griffin T, Cash SB, Stepp JR, Xue D, Long C, Robbat A. Striking changes in tea metabolites due to elevational effects. Food Chem 2018; 264:334-341. [PMID: 29853384 DOI: 10.1016/j.foodchem.2018.05.040] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [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: 01/03/2018] [Revised: 04/30/2018] [Accepted: 05/06/2018] [Indexed: 10/17/2022]
Abstract
Climate effects on crop quality at the molecular level are not well-understood. Gas and liquid chromatography-mass spectrometry were used to measure changes of hundreds of compounds in tea at different elevations in Yunnan Province, China. Some increased in concentration while others decreased by 100's of percent. Orthogonal projection to latent structures-discriminant analysis revealed compounds exhibiting analgesic, antianxiety, antibacterial, anticancer, antidepressant, antifungal, anti-inflammatory, antioxidant, anti-stress, and cardioprotective properties statistically (p = 0.003) differentiated high from low elevation tea. Also, sweet, floral, honey-like notes were higher in concentration in the former while the latter displayed grassy, hay-like aroma. In addition, multivariate analysis of variance showed low elevation tea had statistically (p = 0.0062) higher concentrations of caffeine, epicatechin gallate, gallocatechin, and catechin; all bitter compounds. Although volatiles represent a small fraction of the total mass, this is the first comprehensive report illustrating how normal variations in temperature, 5 °C, due to elevational effects impact tea quality.
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Affiliation(s)
- Nicole Kfoury
- Department of Chemistry, Tufts University, Medford, MA 02155, USA; Tufts University Sensory and Science Center, Medford, MA 02155, USA
| | - Joshua Morimoto
- Department of Chemistry, Tufts University, Medford, MA 02155, USA
| | - Amanda Kern
- Tufts University Sensory and Science Center, Medford, MA 02155, USA
| | - Eric R Scott
- Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Colin M Orians
- Tufts University Sensory and Science Center, Medford, MA 02155, USA; Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Selena Ahmed
- Department of Health and Human Development, Montana State University, Bozeman, MT 59717, USA
| | - Timothy Griffin
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA 02111, USA
| | - Sean B Cash
- Tufts University Sensory and Science Center, Medford, MA 02155, USA; Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA 02111, USA
| | - John Richard Stepp
- Department of Anthropology, University of Florida, Gainesville, FL 32611, USA
| | - Dayuan Xue
- College of Life and Environmental Sciences, Minzu University of China, Beijing, China
| | - Chunlin Long
- College of Life and Environmental Sciences, Minzu University of China, Beijing, China
| | - Albert Robbat
- Department of Chemistry, Tufts University, Medford, MA 02155, USA; Tufts University Sensory and Science Center, Medford, MA 02155, USA.
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14
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Li X, Wei JP, Scott ER, Liu JW, Guo S, Li Y, Zhang L, Han WY. Exogenous Melatonin Alleviates Cold Stress by Promoting Antioxidant Defense and Redox Homeostasis in Camellia sinensis L. Molecules 2018; 23:molecules23010165. [PMID: 29342935 PMCID: PMC6017414 DOI: 10.3390/molecules23010165] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/08/2018] [Accepted: 01/11/2018] [Indexed: 11/16/2022] Open
Abstract
The unprecedented early spring frost that appears as a cold stress adversely affects growth and productivity in tea (Camellia sinensis L.); therefore, it is indispensable to develop approaches to improve the cold tolerance of tea. Here, we investigated the effect of pretreatment with exogenous melatonin on the net photosynthetic rate, the maximum photochemical efficiency of PSII, chlorophyll content, lipid peroxidation, reactive oxygen species (ROS) accumulation, antioxidant potential, and redox homeostasis in leaves of tea plants following cold stress. Our results revealed that cold treatment induced oxidative stress by increasing ROS accumulation, which in turn affected the photosynthetic process in tea leaves. However, treatment with melatonin mitigated cold-induced reductions in photosynthetic capacity by reducing oxidative stress through enhanced antioxidant potential and redox homeostasis. This study provides strong evidence that melatonin could alleviate cold-induced adverse effects in tea plants.
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Affiliation(s)
- Xin Li
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 Meiling Road, Hangzhou 310008, China.
| | - Ji-Peng Wei
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 Meiling Road, Hangzhou 310008, China.
| | - Eric R Scott
- Department of Biology, Tufts University, Medford, MA 02155, USA.
| | - Jian-Wei Liu
- Agricultural Technology Extension Center of Fuyang District, 118 Guihua West Road, Hangzhou 330183, China.
| | - Shuai Guo
- Hangzhou Botanical Garden, 1 Taoyuanling, Hangzhou 310013, China.
| | - Yang Li
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 Meiling Road, Hangzhou 310008, China.
| | - Lan Zhang
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 Meiling Road, Hangzhou 310008, China.
| | - Wen-Yan Han
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, 9 Meiling Road, Hangzhou 310008, China.
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15
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Scott ER, Barchfeld R, Riemenschneider P, Domier CW, Muscatello CM, Sohrabi M, Kaita R, Ren Y, Luhmann NC. Far-infrared tangential interferometer/polarimeter design and installation for NSTX-U. Rev Sci Instrum 2016; 87:11E114. [PMID: 27910494 DOI: 10.1063/1.4960415] [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: 06/06/2023]
Abstract
The Far-infrared Tangential Interferometer/Polarimeter (FIReTIP) system has been refurbished and is being reinstalled on the National Spherical Torus Experiment-Upgrade (NSTX-U) to supply real-time line-integrated core electron density measurements for use in the NSTX-U plasma control system (PCS) to facilitate real-time density feedback control of the NSTX-U plasma. Inclusion of a visible light heterodyne interferometer in the FIReTIP system allows for real-time vibration compensation due to movement of an internally mounted retroreflector and the FIReTIP front-end optics. Real-time signal correction is achieved through use of a National Instruments CompactRIO field-programmable gate array.
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Affiliation(s)
- E R Scott
- Department of Mechanical and Aerospace Engineering, University of California, Davis, California 95616, USA
| | - R Barchfeld
- Department of Applied Science, University of California, Davis, California 95616, USA
| | - P Riemenschneider
- Department of Electrical and Computer Engineering, University of California, Davis, California 95616, USA
| | - C W Domier
- Department of Electrical and Computer Engineering, University of California, Davis, California 95616, USA
| | | | - M Sohrabi
- Department of Electrical and Computer Engineering, University of California, Davis, California 95616, USA
| | - R Kaita
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - Y Ren
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - N C Luhmann
- Department of Electrical and Computer Engineering, University of California, Davis, California 95616, USA
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16
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Bath BD, Scott ER, Phipps JB, White HS. Scanning electrochemical microscopy of iontophoretic transport in hairless mouse skin. Analysis of the relative contributions of diffusion, migration, and electroosmosis to transport in hair follicles. J Pharm Sci 2000; 89:1537-49. [PMID: 11042601 DOI: 10.1002/1520-6017(200012)89:12<1537::aid-jps4>3.0.co;2-j] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [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: 11/07/2022]
Abstract
Scanning electrochemical microscopy (SECM) is used to measure spatially localized diffusive and iontophoretic transport rates in hairless mouse skin. Molecular fluxes within individual hair follicles are quantified by measuring the rate at which redox-active probe molecules emerge from the follicle. The influence of an applied current on the flux of an anion (ascorbate), a cation (ferrocenylmethyltrimethylammonium), and a neutral molecule (acetaminophen) is used to determine the contributions of diffusion, migration, and electroosmosis to iontophoretic transport. The direction of electroosmotic transport is consistent with hair follicles possessing a net negative charge at neutral pH. Electroosmosis results in a modest increase in the transport rate of the neutral molecule (a factor of approximately 2.4x at an iontophoretic current density of 0.1 mA/cm(2)). Larger enhancements in the flux of the electrically charged species are associated with migration. The electroosmotic flow velocity within hair follicles is established to be 0.5 (+/-0.1) microm/s at 0.1 mA/cm(2), independent of the electrical charge of permeant. The net volume flow rate across skin resulting from electroosmosis in hair follicles is estimated to be 0.3 microL/cm(2)h. The results suggest that hair follicles are a significant pathway for electroosmotic solution flow during iontophoresis. The radius of the hair follicle openings in hairless mouse skin is measured to be 21 +/- 5 microm.
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Affiliation(s)
- B D Bath
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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17
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Abstract
PURPOSE To identify the physiological structures in hairless mouse skin responsible for the generation of electroosmotic flow during iontophoresis. Also, to determine the effects of changing the pH of the contacting solution on the magnitude of electroosmotic flow in these structures. METHODS Localized diffusive and iontophoretic fluxes of a neutral molecule, hydroquinone (HQ), across hairless mouse skin were quantified using scanning electrochemical microscopy (SECM). The iontophoretic flux was determined as a function of the direction of the applied current and pH of the contacting solution. RESULTS SECM images of HQ transport recorded during iontophoresis at moderate current densities (+/-0.1 mA/cm2) demonstrate that electroosmotic flow is localized to hair follicles. The direction of flow is from anode to cathode at pH > 3.5 and from cathode to anode at pH <3.5. CONCLUSIONS Electroosmotic flow through hair follicles is an efficient and controllable means of transporting small, electrically neutral molecules across hairless mouse skin. Transport through the appendages is sensitive to the pH of the solution in contact with the skin. The isoelectric point of hair follicles, pI, is estimated to be 3.5 from the dependence of electroosmotic flow on the solution pH.
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Affiliation(s)
- B D Bath
- Department of Chemistry, University of Utah, Salt Lake City 84112, USA
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18
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Bath BD, White HS, Scott ER. Electrically facilitated molecular transport. Analysis of the relative contributions of diffusion, migration, and electroosmosis to solute transport in an ion-exchange membrane. Anal Chem 2000; 72:433-42. [PMID: 10695125 DOI: 10.1021/ac9910637] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [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: 11/30/2022]
Abstract
Electrically facilitated molecular transport in an ion-exchange membrane (Nafion, 1100 equiv wt) has been studied using a scanning electrochemical microscope. The transport rates of ferrocenylmethyltrimethylammonium (a cation), acetaminophen (a neutral molecule), and ascorbate (an anion) through approximately 120-micron-thick membranes were measured as a function of the iontophoretic current passed across the membrane (-1.0 to +1.0 A/cm2). Transport rates were analyzed by employing the Nernst-Planck equation, modified to account for electric field-driven convective transport. Excellent agreement between experimental and theoretical values of the molecular flux was obtained using a single fitting parameter for each molecule (electroosmotic drag coefficient). The electroosmotic velocity of the neutral molecule, acetaminophen, was shown to be a factor of approximately 500 larger than that of the cation ferrocenylmethyltrimethylammonium, a consequence of the electrostatic interaction of the cation with the negatively charged pore walls of the ion-exchange membrane. Electroosmotic transport of ascorbate occurred at a negligible rate due to repulsion of the anion by the cation-selective membrane. These results suggest that electroosmotic velocities of solute molecules are determined by specific chemical interactions of the permeant and membrane and may be very different from the average solution velocity. The efficiency of electroosmotic transport was also shown to be a function of the membrane thickness, in addition to membrane/solute interactions.
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Affiliation(s)
- B D Bath
- Department of Chemistry, University of Utah, Salt Lake City 84112, USA
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Abstract
A review of the mineralogical, isotopic, and chemical properties of the carbonates and associated submicrometer iron oxides and sulfides in Martian meteorite ALH84001 provides minimal evidence for microbial activity. Some magnetites resemble those formed by magnetotactic microorganisms but cubic crystals <50 nm in size and elongated grains <25 nm long are too small to be single-domain magnets and are probably abiogenic. Magnetites with shapes that are clearly unique to magnetotactic bacteria appear to be absent in ALH84001. Magnetosomes have not been reported in plutonic rocks and are unlikely to have been transported in fluids through fractures and uniformly deposited where abiogenic magnetite was forming epitaxially on carbonate. Submicrometer sulfides and magnetites probably formed during shock heating. Carbonates have correlated variations in Ca, Mg, and 18O/16O, magnetite-rich rims, and they appear to be embedded in pyroxene and plagiociase glass. Carbonates with these features have not been identified in carbonaceous chondrites and terrestrial rocks, suggesting that the ALH84001 carbonates have a unique origin. Carbonates and hydrated minerals in ALH84001, like secondary phases in other Martian meteorites, have O and H isotopic ratios favoring formation from fluids that exchanged with the Martian atmosphere. I propose that carbonates originally formed in ALH84001 from aqueous fluids and were subsequently shock heated and vaporized. The original carbonates were probably dolomite-magnesite-siderite assemblages that formed in pores at interstitial sites with minor sulfate, chloride, and phyllosilicates. These phases, like many other volatile-rich phases in Martian meteorites, may have formed as evaporate deposits from intermittent floods.
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Affiliation(s)
- E R Scott
- Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu, USA.
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Abstract
Fayalite grains in chondrules in the oxidized, aqueously altered CV3 chondrite Mokoia have large excesses of radiogenic chromium-53. These excesses indicate the in situ decay of short-lived manganese-53 (half-life = 3.7 million years) and define an initial 53Mn/55Mn ratio of 2.32 (+/-0.18) x 10(-6). This ratio is comparable to values for carbonates in CI and CM chondrites and for several classes of differentiated meteorites. Mokoia fayalites formed 7 to 16 million years after Allende calcium-aluminum-rich inclusions, during hydrothermal activity on a geologically active asteroid after chondritic components had ceased forming in the solar nebula.
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Affiliation(s)
- I D Hutcheon
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA 94551, USA
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21
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Scott ER, Krot AN, Yamaguchi A. Carbonates in fractures of Martian meteorite Allan Hills 84001: petrologic evidence for impact origin. Meteorit Planet Sci 1998; 33:709-719. [PMID: 11543072 DOI: 10.1111/j.1945-5100.1998.tb01677.x] [Citation(s) in RCA: 10] [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: 05/23/2023]
Abstract
Carbonates in Martian meteorite Allan Hills 84001 occur as grains on pyroxene grain boundaries, in crushed zones, and as disks, veins, and irregularly shaped grains in healed pyroxene fractures. Some carbonate disks have tapered Mg-rich edges and are accompanied by smaller, thinner and relatively homogeneous, magnesite microdisks. Except for the microdisks, all types of carbonate grains show the same unique chemical zoning pattern on MgCO3-FeCO3-CaCO3 plots. This chemical characteristic and the close spatial association of diverse carbonate types show that all carbonates formed by a similar process. The heterogeneous distribution of carbonates in fractures, tapered shapes of some disks, and the localized occurrence of Mg-rich microdisks appear to be incompatible with growth from an externally derived CO2-rich fluid that changed in composition over time. These features suggest instead that the fractures were closed as carbonates grew from an internally derived fluid and that the microdisks formed from a residual Mg-rich fluid that was squeezed along fractures. Carbonate in pyroxene fractures is most abundant near grains of plagioclase glass that are located on pyroxene grain boundaries and commonly contain major or minor amounts of carbonate. We infer that carbonates in fractures formed from grain boundary carbonates associated with plagiociase that were melted by impact and dispersed into the surrounding fractured pyroxene. Carbonates in fractures, which include those studied by McKay et al. (1996), could not have formed at low temperatures and preserved mineralogical evidence for Martian organisms.
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Affiliation(s)
- E R Scott
- Hawai'i Institute of Geophysics and Planetology, University of Hawai'i at Manoa, Honolulu 96822, USA.
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22
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Abstract
The meteorite ALH84001--a shocked igneous rock of probable martian origin-contains chemically and isotopically heterogeneous carbonate globules, associated with which are organic and inorganic structures that have been interpreted as possible fossil remains of ancient martian biota. A critical assumption underlying this suggestion is that the carbonates formed from low-temperature fluids penetrating the cracks and voids of the host rock. Here we report petrological studies of ALH84001 which investigate the effects of shock on the various mineralogical components of the rock. We find that carbonate, plagioclase and silica were melted and partly redistributed by the same shock event responsible for the intense local crushing of pyroxene in the meteorite. Texture and compositional data show that, during the period of shock decompression, monomineralic melts were injected into pyroxene fractures that were subsequently cooled and resealed within seconds. Our results therefore suggest that the carbonates in ALH84001 could not have formed at low temperatures, but instead crystallized from shock-melted material; this conclusion weakens significantly the arguments that these carbonates could host the fossilized remnants of biogenic activity.
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Affiliation(s)
- E R Scott
- Hawaii Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu 96822, USA.
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23
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Abstract
Physiological structures associated with iontophoretic paths in hairless mouse skin and two cultured skin models ("EpiDerm" by Mattek, Corp., and "SKIN2" by Advanced Tissue Sciences, Inc.) are reported. Visualization of ionic paths at current densities between 20 and 100 microA/ cm2 is accomplished by the counterdirectional transport of Fe(CN)6(4-) and Fe3+, resulting in the controlled precipitation of colloidal Prussian blue, Fe4[Fe(CN)6]3, at sites of high ionic conductivity. Examination of the Fe4[Fe(CN)6]3-stained tissues using optical microscopy allows unequivocal assignment of iontophoretic paths to physiological structures in the stratum corneum. Deposition of Fe4[Fe(CN)6]3 occurs exclusively at hair follicles in hairless mouse skin, indicating that these appendages provide highly conductive porous paths during iontophoresis. In contrast, the counterdirectional transport of Fe(CN)6(4-) and Fe3+ across cultured skin models, which lack appendages, results in the deposition of Fe4-[Fe(CN)6]3 along the boundaries of corneocytes. This observation suggests that paracellular iontophoretic transport through lipid bilayer regions is the predominant transport path in the absence of low-resistance pores.
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Affiliation(s)
- R D Lee
- Department of Chemistry, University of Utah, Salt Lake City 84112, USA
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24
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Abstract
Scanning electrochemical microscopy (SECM) was used to image spatial variations in the molecular flux of Fe(CN)6(-4) across excised hairless and nude mouse skin. The SECM response is specific to electroactive molecules, allowing selective imaging of the flux of Fe(CN)6(-4) in multicomponent ionic solutions. Quantitative SECM image analysis demonstrated that 40% to 60% of the total Fe(CN)6(-4) flux occurred through appendages in the skin. SECM analysis of skin samples exposed to a known transport enhancer, sodium dodecylsulfate, indicated that the increase in the ion transport rate occurred exclusively in nonporous skin tissue.
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Affiliation(s)
- E R Scott
- Medtronic, Inc., Brooklyn Center, Minnesota
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25
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Abstract
Two methods are reported that allow visualization of high conductance paths in skin at current densities typically used during clinical iontophoretic drug delivery (10-200 microA/cm2). In the first method, the counter-directional iontophoretic transport of Fe(CN)6(4-) and Fe3+ across skin results in the precipitation of colloidal prussian blue, Fe4[Fe(CN)6]3, at sites of high iontophoretic flux. The appearance of localized deposits of Fe4[Fe(CN)6]3 is recorded by video microscopy and used to document the activation of low-resistance paths. In the second method, the ionic flux of Fe(CN)6(4-) through pores is directly imaged by scanning electrochemical microscopy (SECM). Both methods demonstrate that the iontophoretic flux across skin is highly localized. Activation of low-resistance pores in hairless mouse skin is shown to occur during iontophoresis. The spatial density of current carrying pores increases from 0 to 100-600 pores/cm2 during the first 30-60 min of iontophoresis. At longer times, the active pore density approaches a quasi-steady-state value that is proportional to the applied current density. The total conductance of the skin is proportional to the number of pores, consistent with a model of conduction in skin that is comprised of low-resistivity pores in parallel with a high-resistivity bulk phase. The contribution of pores to the total skin conductance during iontophoresis increases from an initial value of 0-5% to a quasi-steady-state value of 50-95%.
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Affiliation(s)
- E R Scott
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis 55455
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26
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Scott ER, White HS, Phipps JB. Iontophoretic transport through porous membranes using scanning electrochemical microscopy: application to in vitro studies of ion fluxes through skin. Anal Chem 1993; 65:1537-45. [PMID: 8328671 DOI: 10.1021/ac00059a010] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.8] [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: 01/29/2023]
Abstract
Scanning electrochemical microscopy (SECM) is used to map localized iontophoretic fluxes of electroactive species through porous membranes. A method is described that allows both the rate of transport of species from a microscopic pore and the pore's diameter to be measured. SECM images and analyses of synthetic porous membranes (track-etched polycarbonate and mica membranes) and hairless mouse skin are reported. Preliminary analysis of SECM images of the mouse skin indicates that a significant percentage of the iontophoretic flux occurs through pores associated with hair follicles.
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Affiliation(s)
- E R Scott
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis 55455
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27
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Margolick JB, Scott ER, Chadwick KR, Shapiro HM, Hetzel AD, Smith SJ, Vogt RF. Comparison of lymphocyte immunophenotypes obtained simultaneously from two different data acquisition and analysis systems on the same flow cytometer. Cytometry 1992; 13:198-203. [PMID: 1547669 DOI: 10.1002/cyto.990130215] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Immunophenotyping of different lymphocyte populations was carried out in parallel on 113 consecutively received specimens of human peripheral blood using 2 different data acquisition and analysis systems (EPICS C and 4Cyte-Acmecyte) on the same flow cytometer (EPICS C). The phenotypes analyzed were CD3+, CD4+, CD8+ CD56+ CD16+ CD3-, TCR-gamma delta+ CD8-, and TCR-gamma delta+ CD8+. Both HIV- and HIV+ specimens were used for this study, including some with CD4 levels as low as 2% of all lymphocytes. Despite differences in gating procedures and shapes of bitmap (rectilinear vs. "amorphous"), the 2 methods agreed to within 2% positive cells in 97% of the cases. Although some statistically significant biases in the methods were observed, these were small and not biologically important. We conclude that both methods of data acquisition and analysis, as employed by experienced operators on the EPICS C flow cytometer, gave essentially equivalent results for lymphocyte sub-populations in peripheral blood preparations.
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Affiliation(s)
- J B Margolick
- Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland 21205
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Margolick JB, Scott ER, Odaka N, Saah AJ. Flow cytometric analysis of gamma delta T cells and natural killer cells in HIV-1 infection. Clin Immunol Immunopathol 1991; 58:126-38. [PMID: 1824568 DOI: 10.1016/0090-1229(91)90154-3] [Citation(s) in RCA: 47] [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] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have previously shown that HIV-1 seropositivity is associated with an increase in the difference between the number of CD3+ lymphocytes and the total number of CD4+ and CD8+ lymphocytes [CD3 - (CD4 + CD8)] among peripheral blood lymphocytes (PBL). To investigate the cellular basis of this increase, PBL from seronegative (SN) and AIDS-free seropositive (SP) homosexual men and intravenous drug users were analyzed by two-color flow cytometry. Results showed that SP compared to SN manifested the expected elevation in calculated [CD3 - (CD4 + CD8)] cells (87 vs 28 cells/mm3; P less than 0.001). Only small differences in lymphocyte populations that could contribute to this increase were observed, namely lymphocytes expressing the CD3+CD4-CD8-phenotype (67 vs 56 cells/mm3; P greater than 0.10) or the CD8dim phenotype (135 vs 142 cells/mm3; P greater than 0.10). However, SP had significantly lower numbers of cells expressing the CD56+CD3- phenotype characteristic of natural killer cells (81 vs 170 cells/mm3; P less than 0.001) and significantly higher numbers of T cells expressing the gamma delta T cell receptor (TCR) (81 vs 62 cells/mm3; P = 0.10). The latter difference was primarily due to higher numbers of cells coexpressing gamma delta-TCR and low levels of CD8 (27 vs 15 cells/mm3; P = 0.009). These data suggest that HIV-1 seropositivity is associated with low numbers of natural killer cells and high numbers of CD8+ gamma delta-TCR lymphocytes. Changes in these populations may reflect altered host defense against HIV-1 or altered T cell kinetics in the presence of HIV-1 infection.
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Affiliation(s)
- J B Margolick
- Department of Environmental Health Sciences, Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland 21205
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Margolick JB, McArthur JC, Scott ER, McArthur JH, Cohn S, Farzadegan H, Polk BF. Flow cytometric quantitation of T cell phenotypes in cerebrospinal fluid and peripheral blood of homosexual men with and without antibodies to human immunodeficiency virus, type I. J Neuroimmunol 1988; 20:73-81. [PMID: 3263391 DOI: 10.1016/0165-5728(88)90116-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Two-color flow cytometry was used to analyze T cell subsets (total (CD3), helper-inducer (CD4), and suppressor-cytotoxic (CD8] in paired specimens of cerebrospinal fluid (CSF) and peripheral blood of 66 homosexual men, including 62 with antibodies to human immunodeficiency virus, type 1 (HIV-1). With the exception of one traumatic specimen, all of the CSF specimens, 52 of which had less than or equal to 5 lymphocytes/mm3, were evaluated fully, with the number of lymphocytes counted for each antibody ranging from 200 to 2933 (mean = 1129). Proportions of CD3, CD4, and CD8 lymphocytes in CSF were very highly correlated with the proportions of these cells in the peripheral blood (r = 0.87, 0.96, and 0.94, respectively), as was the CD4/CD8 ratio (r = 0.98). These strong correlations were present in each of seven subgroups of study subjects defined on the basis of detailed neurologic examination, neuropsychological testing, and the presence or absence of antibodies to HIV-1. In the population studied, T cell phenotypes in CSF as analyzed by two-color flow cytometry were largely determined by the corresponding proportions in the peripheral blood.
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Affiliation(s)
- J B Margolick
- Department of Environmental Health Sciences, Johns Hopkins Medical Institutions, Baltimore, MD 21205
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Williams RC, Leone CW, Jeffcoat MK, Scott ER, Goldhaber P. Tetracycline treatment of periodontal disease in the beagle dog. I. Clinical and radiographic course over 12 months-maximal effect on rate of alveolar bone loss. J Periodontal Res 1981; 16:659-65. [PMID: 6460864 DOI: 10.1111/j.1600-0765.1981.tb01004.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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31
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Scott ER. A national association. Dent Tech 1966; 19:106-8 passim. [PMID: 5224989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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