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Chandler GA, Ruiz CL, Cooper GW, Torres JA, Mangan MA, Whitlow GM, Ampleford DJ, Jones MC, Buckles RA, Moy KJ, Garza I, Staska M, Wolverton A, Davis B. Neutron time-of-flight detectors (nTOF) used at Sandia's Z-Machine. Rev Sci Instrum 2022; 93:113531. [PMID: 36461459 DOI: 10.1063/5.0101544] [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: 06/01/2022] [Accepted: 10/04/2022] [Indexed: 06/17/2023]
Abstract
Neutron time-of-flight (nTOF) detectors have been used on Sandia National Laboratories' Z-Machine for inertial confinement fusion and magnetized liner fusion experiments to infer physics parameters including the apparent fuel-ion temperature, neutron yield, the magnetic-radius product (BR), and the liner rho-r. Single-paddle, dual-paddle, and co-axial scintillation nTOF detectors are used in axial lines-of-sight (LOS) and LOS that are 12° from the midplane. Detector fabrication, characterization, and calibration are discussed.
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Affiliation(s)
- G A Chandler
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - C L Ruiz
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - G W Cooper
- Department of Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - J A Torres
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - M A Mangan
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - G M Whitlow
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - D J Ampleford
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - M C Jones
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - R A Buckles
- National Nuclear Security Site, Las Vegas Operations, Las Vegas, Nevada 89030, USA
| | - K J Moy
- National Nuclear Security Site, Special Technologies Laboratory, Santa Barbara, California 93111, USA
| | - I Garza
- National Nuclear Security Site, Las Vegas Operations, Las Vegas, Nevada 89030, USA
| | - M Staska
- National Nuclear Security Site, Special Technologies Laboratory, Santa Barbara, California 93111, USA
| | - A Wolverton
- National Nuclear Security Site, Las Vegas Operations, Las Vegas, Nevada 89030, USA
| | - B Davis
- National Nuclear Security Site, Las Vegas Operations, Las Vegas, Nevada 89030, USA
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Elliott E, Chassagne F, Aubouy A, Deharo E, Souvanasy O, Sythamala P, Sydara K, Lamxay V, Manithip C, Torres JA, Bourdy G. Forest Fevers: traditional treatment of malaria in the southern lowlands of Laos. J Ethnopharmacol 2020; 249:112187. [PMID: 31476439 DOI: 10.1016/j.jep.2019.112187] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 05/30/2019] [Revised: 08/12/2019] [Accepted: 08/26/2019] [Indexed: 05/20/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Malaria is still a highly challenging public health issue in southern Lao PDR, with increasing cases of artemisinin resistance and Plasmodium vivax infections which are more complicated to treat. Traditional medicine has a long history of use in Laos, and is primarily practised by traditional village healers, who possess unique bodies of transmitted knowledge focused on herbal prescriptions, including those for the treatment of malaria. Villagers also use plants for healthcare in the home. The aim of the study is to document local fever concepts and use of herbal remedies, and examine whether they may have potential as complementary treatments against malaria. MATERIALS AND METHODS The study took place in Champasak province in the far south of Laos, in primarily lowland areas. First, 35 traditional healers across the 10 districts of the province were interviewed to elicit details about knowledge and treatment of fevers. Second, a household survey was conducted in a village in a malaria-endemic area; 97 households were interviewed on fever incidence, differentiation, treatment-seeking behaviour and knowledge of plant-based remedies for fevers. Plants indicated by both healers and villagers were collected and voucher specimens deposited in the herbarium of the National University of Laos for identification. RESULTS Malaria is a well-known pathology among the healers and villagers of lowland Champasak province; biomedical treatments are preferentially used, but traditional medicine is a popular complementary method, especially in chronic cases with additional symptoms. 30 different fever types were recorded, which were usually named symptomatically, and grouped into 12 categories. Some were described as forms of malaria, which was conceived as a dynamic, changing pathology affecting many body systems. Healers formulate treatments based on symptoms and the person's constitution, and with the intention of creating specific pharmacological actions associated with temperature or flavours. 11 of the healers gave prescriptions for malaria (27 in total), including 47 identified plant species. The most-used plants (4 or more use-reports) were also the most cited in the literature for use against malaria, demonstrating a correspondence between Lao healers and other traditional medical systems. Furthermore, some of these species show promising results for future research, especially Amorphophallus paeniifolius (Dennst.) Nicolson and Alocasia macrorrhizos (L.) G. Don. CONCLUSION Traditional healers are important actors in the treatment of malaria in southern Laos, and herbal remedies should be evaluated further by the use of reverse treatment outcome trials, especially those which may be of use as complementary remedies in treating P. vivax. Initiatives on knowledge transmission, medicinal plant conservation and healthcare integration are also urgently needed.
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Affiliation(s)
| | - François Chassagne
- UMR 152 Pharmadev, IRD, Université de Toulouse, France; Center for the Study of Human Health, Emory University, Atlanta, GA, USA
| | - Agnès Aubouy
- UMR 152 Pharmadev, IRD, Université de Toulouse, France
| | - Eric Deharo
- UMR 152 Pharmadev, IRD, Université de Toulouse, France
| | - Outhay Souvanasy
- Department of Traditional Medicine, Champasak Regional Hospital, Pakse, Lao Peoples Democratic Republic
| | - Phaiboun Sythamala
- Department of Traditional Medicine, Champasak Regional Hospital, Pakse, Lao Peoples Democratic Republic
| | - Kongmany Sydara
- Institute of Traditional Medicine, Vientiane, Lao Peoples Democratic Republic
| | - Vichith Lamxay
- Department of Biology, Faculty of Natural Sciences, National University of Laos, Vientiane, Lao Peoples Democratic Republic
| | - Chantanom Manithip
- Faculty of Pharmacy, University of Health Sciences, Vientiane, Lao Peoples Democratic Republic
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Torres JA, Silva MC, Lopes JH, Nogueira AE, Nogueira FGE, Corrêa AD. Development of a reusable and sustainable biocatalyst by immobilization of soybean peroxidase onto magnetic adsorbent. Int J Biol Macromol 2018; 114:1279-1287. [PMID: 29578014 DOI: 10.1016/j.ijbiomac.2018.03.136] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [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: 02/21/2018] [Revised: 03/14/2018] [Accepted: 03/22/2018] [Indexed: 01/09/2023]
Abstract
In this work we synthesized an activated carbon/magnetite composite by a simple co-precipitation method. The activated carbon (AC) was synthesized from the solid waste obtained in the extraction process of the peroxidase enzyme and the magnetic composite was used as support for the immobilization of soybean peroxidase (SP). After the determination of the optimal immobilization parameters, a 100% yield was achieved under the following conditions: support:enzyme proportion of 1.0:0.05 g, equilibration time of 7 h, pH 3.0 (citrate buffer phosphate 0.1 mol L-1) and temperature of 50 °C. The determination of pH to the point of zero charge was also done to assist in the understanding of the immobilization process at different pH values. Several characterization techniques were used, such as thermogravimetric analysis, elemental analysis composition, X-ray powder diffraction, Fourier transform infrared spectroscopy and Scanning electron microscopy. The biocatalyst presented excellent operational stability and was reused for 11 consecutive cycles. The magnetic properties inserted in the AC contributed to the removal of the biocatalyst from the reaction medium without interfering in the adsorptive characteristics of the AC. Thus, the activated carbon/magnetite composite can be applied to different research fields with high performance.
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Affiliation(s)
- J A Torres
- Department of Chemistry, Universidade Federal de Lavras, Lavras 37200-000, Brazil.
| | - M C Silva
- Department of Chemistry, Universidade Federal de São João Del Rei, 31270-901, Brazil
| | - J H Lopes
- Laboratory of Engineering and Products Chemistry (LEQUIP), Department of Materials Engineering and Bioprocess (DEMBIO), School of Chemical Engineering (FEQ) - UNICAMP, University of Campinas - UNICAMP, 13083-852 Campinas, SP, Brazil
| | - A E Nogueira
- Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), 13083-970 Campinas, São Paulo, Brazil
| | - F G E Nogueira
- Department of Chemistry Engineering, Universidade Federal de São Carlos, São Carlos 13565-905, Brazil.
| | - A D Corrêa
- Department of Chemistry, Universidade Federal de Lavras, Lavras 37200-000, Brazil.
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Hahn KD, Chandler GA, Ruiz CL, Cooper GW, Gomez MR, Slutz S, Sefkow AB, Sinars DB, Hansen SB, Knapp PF, Schmit PF, Harding E, Jennings CA, Awe TJ, Geissel M, Rovang DC, Torres JA, Bur JA, Cuneo ME, Glebov VY, Harvey-Thompson AJ, Herrman MC, Hess MH, Johns O, Jones B, Lamppa DC, Lash JS, Martin MR, McBride RD, Peterson KJ, Porter JL, Reneker J, Robertson GK, Rochau GA, Savage ME, Smith IC, Styron JD, Vesey RA. Fusion-neutron measurements for magnetized liner inertial fusion experiments on the Z accelerator. ACTA ACUST UNITED AC 2016. [DOI: 10.1088/1742-6596/717/1/012020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Torres JA, Sastre J, Vivanco F, Sanz Maroto A, de Las Heras M, Pastor-Vargas C. Clinical Characteristics of Patients Sensitized to Siberian Hamster. J Investig Allergol Clin Immunol 2016; 26:113-5. [PMID: 27164628 DOI: 10.18176/jiaci.0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- J A Torres
- Department of Allergy, Fundación Jimenez Diaz, Madrid, Spain
| | - J Sastre
- Department of Allergy, Fundación Jimenez Diaz, Madrid, Spain.,Department of Medicine, Universidad Autónoma de Madrid, CIBERES, Instituto Carlos III, Madrid, Spain
| | - F Vivanco
- Department of Immunology, IIS-Fundación Jimenez Diaz, Madrid, Spain.,Department of Biochemistry and Molecular Biology I, Universidad Complutense de Madrid, Spain
| | - A Sanz Maroto
- Department of Immunology, IIS-Fundación Jimenez Diaz, Madrid, Spain
| | - M de Las Heras
- Department of Allergy, Fundación Jimenez Diaz, Madrid, Spain
| | - C Pastor-Vargas
- Department of Immunology, IIS-Fundación Jimenez Diaz, Madrid, Spain
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6
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Styron JD, Cooper GW, Ruiz CL, Hahn KD, Chandler GA, Nelson AJ, Torres JA, McWatters BR, Carpenter K, Bonura MA. Predicting the sensitivity of the beryllium/scintillator layer neutron detector using Monte Carlo and experimental response functions. Rev Sci Instrum 2014; 85:11E617. [PMID: 25430363 DOI: 10.1063/1.4896176] [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: 06/04/2023]
Abstract
A methodology for obtaining empirical curves relating absolute measured scintillation light output to beta energy deposited is presented. Output signals were measured from thin plastic scintillator using NIST traceable beta and gamma sources and MCNP5 was used to model the energy deposition from each source. Combining the experimental and calculated results gives the desired empirical relationships. To validate, the sensitivity of a beryllium/scintillator-layer neutron activation detector was predicted and then exposed to a known neutron fluence from a Deuterium-Deuterium fusion plasma (DD). The predicted and the measured sensitivity were in statistical agreement.
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Affiliation(s)
- J D Styron
- Department of Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - G W Cooper
- Department of Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - C L Ruiz
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - K D Hahn
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Chandler
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - A J Nelson
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J A Torres
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - B R McWatters
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - Ken Carpenter
- Department of Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - M A Bonura
- Department of Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
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7
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Bonura MA, Ruiz CL, Fehl DL, Cooper GW, Chandler G, Hahn KD, Nelson AJ, Styron JD, Torres JA. A technique for verifying the input response function of neutron time-of-flight scintillation detectors using cosmic rays. Rev Sci Instrum 2014; 85:11D633. [PMID: 25430209 DOI: 10.1063/1.4896958] [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: 06/04/2023]
Abstract
An accurate interpretation of DD or DT fusion neutron time-of-flight (nTOF) signals from current mode detectors employed at the Z-facility at Sandia National Laboratories requires that the instrument response functions (IRF's) be deconvolved from the measured nTOF signals. A calibration facility that produces detectable sub-ns radiation pulses is typically used to measure the IRF of such detectors. This work, however, reports on a simple method that utilizes cosmic radiation to measure the IRF of nTOF detectors, operated in pulse-counting mode. The characterizing metrics reported here are the throughput delay and full-width-at-half-maximum. This simple approach yields consistent IRF results with the same detectors calibrated in 2007 at a LINAC bremsstrahlung accelerator (Idaho State University). In particular, the IRF metrics from these two approaches and their dependence on the photomultipliers bias agree to within a few per cent. This information may thus be used to verify if the IRF for a given nTOF detector employed at Z has changed since its original current-mode calibration and warrants re-measurement.
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Affiliation(s)
- M A Bonura
- Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - C L Ruiz
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87111, USA
| | - D L Fehl
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87111, USA
| | - G W Cooper
- Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - G Chandler
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87111, USA
| | - K D Hahn
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87111, USA
| | - A J Nelson
- Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - J D Styron
- Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - J A Torres
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87111, USA
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8
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Hahn KD, Cooper GW, Ruiz CL, Fehl DL, Chandler GA, Knapp PF, Leeper RJ, Nelson AJ, Smelser RM, Torres JA. Fusion-neutron-yield, activation measurements at the Z accelerator: design, analysis, and sensitivity. Rev Sci Instrum 2014; 85:043507. [PMID: 24784607 DOI: 10.1063/1.4870779] [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] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present a general methodology to determine the diagnostic sensitivity that is directly applicable to neutron-activation diagnostics fielded on a wide variety of neutron-producing experiments, which include inertial-confinement fusion (ICF), dense plasma focus, and ion beam-driven concepts. This approach includes a combination of several effects: (1) non-isotropic neutron emission; (2) the 1/r(2) decrease in neutron fluence in the activation material; (3) the spatially distributed neutron scattering, attenuation, and energy losses due to the fielding environment and activation material itself; and (4) temporally varying neutron emission. As an example, we describe the copper-activation diagnostic used to measure secondary deuterium-tritium fusion-neutron yields on ICF experiments conducted on the pulsed-power Z Accelerator at Sandia National Laboratories. Using this methodology along with results from absolute calibrations and Monte Carlo simulations, we find that for the diagnostic configuration on Z, the diagnostic sensitivity is 0.037% ± 17% counts/neutron per cm(2) and is ∼ 40% less sensitive than it would be in an ideal geometry due to neutron attenuation, scattering, and energy-loss effects.
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Affiliation(s)
- K D Hahn
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123, USA
| | - G W Cooper
- Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - C L Ruiz
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123, USA
| | - D L Fehl
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123, USA
| | - G A Chandler
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123, USA
| | - P F Knapp
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123, USA
| | - R J Leeper
- Los Alamos National Laboratories, Plasma Physics Group, Los Alamos, New Mexico 87545, USA
| | - A J Nelson
- Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - R M Smelser
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123, USA
| | - J A Torres
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123, USA
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9
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Gayán E, Torres JA, Alvarez I, Condón S. Selection of process conditions by risk assessment for apple juice pasteurization by UV-heat treatments at moderate temperatures. J Food Prot 2014; 77:207-15. [PMID: 24490914 DOI: 10.4315/0362-028x.jfp-13-255] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The effect of bactericidal UV-C treatments (254 nm) on Escherichia coli O157:H7 suspended in apple juice increased synergistically with temperature up to a threshold value. The optimum UV-C treatment temperature was 55 °C, yielding a 58.9% synergistic lethal effect. Under these treatment conditions, the UV-heat (UV-H55 °C) lethal variability achieving 5-log reductions had a logistic distribution (α = 37.92, β = 1.10). Using this distribution, UV-H55 °C doses to achieve the required juice safety goal with 95, 99, and 99.9% confidence were 41.17, 42.97, and 46.00 J/ml, respectively, i.e., doses higher than the 37.58 J/ml estimated by a deterministic procedure. The public health impact of these results is that the larger UV-H55 °C dose required for achieving 5-log reductions with 95, 99, and 99.9% confidence would reduce the probability of hemolytic uremic syndrome in children by 76.3, 88.6, and 96.9%, respectively. This study illustrates the importance of including the effect of data variability when selecting operational parameters for novel and conventional preservation processes to achieve high food safety standards with the desired confidence level.
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Affiliation(s)
- E Gayán
- Food Science and Technology, University of Zaragoza, C/ Miguel Servet 177, CP 50013, Zaragoza, Spain
| | - J A Torres
- Food Processing Engineering Group, Department of Food Science and Technology, Oregon State University, Corvallis, Oregon 97331, USA
| | - I Alvarez
- Food Science and Technology, University of Zaragoza, C/ Miguel Servet 177, CP 50013, Zaragoza, Spain
| | - S Condón
- Food Science and Technology, University of Zaragoza, C/ Miguel Servet 177, CP 50013, Zaragoza, Spain.
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Jones TH, Torres JA, Spande TF, Garraffo HM, Blum MS, Snelling RR. Chemistry of venom alkaloids in someSolenopsis (Diplorhoptrum) species from Puerto Rico. J Chem Ecol 2013; 22:1221-36. [PMID: 24226081 DOI: 10.1007/bf02266962] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/1995] [Accepted: 02/29/1996] [Indexed: 11/30/2022]
Abstract
A number of 15-carbon alkaloids have been identified in venom extracts of four Puerto Rican species of ants in the genusSolenopsis (Diplorhoptrum). Workers of a species from El Verde produced thecis andtrans isomers of 2-methyl-6-nonylpiperidine with the latter isomer predominating. The same compounds were identified in queens of a species from Río Grande, but in this species no alkaloids were detected in worker extracts. Workers of aDiplorhoptrum species collected on Mona Island produced primarily atrans-2-methyl-6-(Z-4-nonenyl)piperidine,3, with smaller amounts of thecis isomer, whereas the major compound found in the queens of the same species on Mona Island was (5Z,9Z)-3-hexyl-5-methylindolizidine, identical with the alkaloid produced by queens of a species collected on Cabo Rojo. Surprisingly, workers of the Cabo Rojo species produced (5Z,9Z)- and (5E,9E)-3-butyl-5-propylindolizidine (4 and5, respectively) reported earlier as the 223AB indolizidines from skins of dendrobatid frogs. The possible significance of the qualitative and quantitative differences in the venom alkaloids synthesized by queens and workers is discussed as is the possibility that ants containing such alkaloids may serve as a dietary source for the skin alkaloids used by certain frogs in chemical defense.
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Affiliation(s)
- T H Jones
- Department of Chemistry, Virginia Military Institute, 24450-0304, Lexington, Virginia
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11
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Ruiz CL, Chandler GA, Cooper GW, Fehl DL, Hahn KD, Leeper RJ, McWatters BR, Nelson AJ, Smelser RM, Snow CS, Torres JA. Progress in obtaining an absolute calibration of a total deuterium-tritium neutron yield diagnostic based on copper activation. Rev Sci Instrum 2012; 83:10D913. [PMID: 23126916 DOI: 10.1063/1.4729495] [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: 06/01/2023]
Abstract
The 350-keV Cockroft-Walton accelerator at Sandia National laboratory's Ion Beam facility is being used to calibrate absolutely a total DT neutron yield diagnostic based on the (63)Cu(n,2n)(62)Cu(β+) reaction. These investigations have led to first-order uncertainties approaching 5% or better. The experiments employ the associated-particle technique. Deuterons at 175 keV impinge a 2.6 μm thick erbium tritide target producing 14.1 MeV neutrons from the T(d,n)(4)He reaction. The alpha particles emitted are measured at two angles relative to the beam direction and used to infer the neutron flux on a copper sample. The induced (62)Cu activity is then measured and related to the neutron flux. This method is known as the F-factor technique. Description of the associated-particle method, copper sample geometries employed, and the present estimates of the uncertainties to the F-factor obtained are given.
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Affiliation(s)
- C L Ruiz
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA.
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12
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Nelson AJ, Ruiz CL, Cooper GW, Chandler GA, Fehl DL, Hahn KD, Leeper RJ, Smelser R, Torres JA. A novel method for modeling the neutron time of flight detector response in current mode to inertial confinement fusion experiments (invited). Rev Sci Instrum 2012; 83:10D915. [PMID: 23126918 DOI: 10.1063/1.4742140] [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: 06/01/2023]
Abstract
A novel method for modeling the neutron time of flight (nTOF) detector response in current mode for inertial confinement fusion experiments has been applied to the on-axis nTOF detectors located in the basement of the Z-Facility. It will be shown that this method can identify sources of neutron scattering, and is useful for predicting detector responses in future experimental configurations, and for identifying potential sources of neutron scattering when experimental set-ups change. This method can also provide insight on how much broadening neutron scattering contributes to the primary signals, which is then subtracted from them. Detector time responses are deconvolved from the signals, allowing a transformation from dN/dt to dN/dE, extracting neutron spectra at each detector location; these spectra are proportional to the absolute yield.
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Affiliation(s)
- A J Nelson
- Department of Chemical & Nuclear Engineering, University of New Mexico, Albuquerque, 87131, USA.
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13
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Cooper GW, Ruiz CL, Leeper RJ, Chandler GA, Hahn KD, Nelson AJ, Torres JA, Smelser RM, McWatters BR, Bleuel DL, Yeamans CB, Knittel KM, Casey DT, Frenje JA, Gatu Johnson M, Petrasso RD, Styron JD. Copper activation deuterium-tritium neutron yield measurements at the National Ignition Facility. Rev Sci Instrum 2012; 83:10D918. [PMID: 23126920 DOI: 10.1063/1.4746999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A DT neutron yield diagnostic based on the reactions, (63)Cu(n,2n)(62)Cu(β(+)) and (65)Cu(n,2n)( 64) Cu(β(+)), has been fielded at the National Ignition Facility (NIF). The induced copper activity is measured using a NaI γ-γ coincidence system. Uncertainties in the 14-MeV DT yield measurements are on the order of 7% to 8%. In addition to measuring yield, the ratio of activities induced in two, well-separated copper samples are used to measure the relative anisotropy of the fuel ρR to uncertainties as low as 5%.
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Affiliation(s)
- G W Cooper
- Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, 87131, USA.
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Hahn KD, Ruiz CL, Cooper GW, Nelson AJ, Chandler GA, Leeper RJ, McWatters BR, Smelser RM, Torres JA. Calibration of neutron-yield diagnostics in attenuating and scattering environments. Rev Sci Instrum 2012; 83:10D914. [PMID: 23126917 DOI: 10.1063/1.4732067] [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: 06/01/2023]
Abstract
We have performed absolute calibrations of a fusion-neutron-yield copper-activation diagnostic in environments that significantly attenuate and scatter neutrons. We have measured attenuation and scattering effects and have compared the measurements to Monte Carlo simulations using the Monte Carlo N-Particle code. We find that measurements and simulations are consistent within 10%.
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Affiliation(s)
- K D Hahn
- Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87111, USA.
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Miller EK, Abbott RQ, McKenna I, Macrum G, Baker D, Tran V, Rodriguez E, Kaufman MI, Tibbits A, Silbernagel CT, Waltman TB, Herrmann HW, Kim YH, Mack JM, Young CS, Caldwell SE, Evans SC, Sedillo TJ, Stoeffl W, Grafil E, Liebman J, Beeman B, Watts P, Carpenter A, Horsfied CJ, Rubery MS, Chandler GA, Torres JA, Smelser RM. Mach-Zehnder recording systems for pulsed power diagnostics. Rev Sci Instrum 2012; 83:10D719. [PMID: 23126893 DOI: 10.1063/1.4733310] [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: 06/01/2023]
Abstract
Fiber-optic transmission and recording systems, based on Mach-Zehnder modulators, have been developed and installed at the National Ignition Facility (NIF), and are being developed for other pulsed-power facilities such as the Z accelerator at Sandia, with different requirements. We present the design and performance characteristics for the mature analog links, based on the system developed for the Gamma Reaction History diagnostic at the OMEGA laser and at NIF. For a single detector channel, two Mach-Zehnders are used to provide high dynamic range at the full recording bandwidth with no gaps in the coverage. We present laboratory and shot data to estimate upper limits on the radiation effects as they impact recorded data quality. Finally, we will assess the technology readiness level for mature and developing implementations of Mach-Zehnder links for these environments.
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Affiliation(s)
- E K Miller
- National Security Technologies, LLC, Santa Barbara and Livermore, California 93111, USA.
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16
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Lopez JA, Correa A, Navon-Venezia S, Correa AL, Torres JA, Briceño DF, Montealegre MC, Quinn JP, Carmeli Y, Villegas MV. Intercontinental spread from Israel to Colombia of a KPC-3-producing Klebsiella pneumoniae strain. Clin Microbiol Infect 2011; 17:52-6. [PMID: 20219078 DOI: 10.1111/j.1469-0691.2010.03209.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In 2008, an increase in the prevalence of carbapenem-resistant Klebsiella pneumoniae was noted in a 286-bed tertiary case hospital in Colombia, where 84 patients (32 infected and 52 colonized) had positive cultures. The identified index patient came from Israel for a liver transplantation. High level carbapenem resistance was observed. Polymyxin B and tigecycline were the only two antibiotics that remained active. PCR-restriction fragment length polymorphism analysis and sequencing revealed blaKPC-3 in the major clone, which was indistinguishable from the K. pneumoniae carbapenemase-3-producing clone described previously in Israel. This exemplifies the threat posed by the global spread of K. pneumoniae carbapenemase-producing pathogens.
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Affiliation(s)
- J A Lopez
- Hospital Pablo Tobón Uribe, Medellín, Colombia
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17
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Torres JA, Sastre J, De las Heras M, Requena L, del Haro R, Cazorla A. Irritative contact dermatitis due to gentian violet (methylrosaniline chloride) in an airplane passenger: a case report. J Investig Allergol Clin Immunol 2009; 19:67-68. [PMID: 19274935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Affiliation(s)
- J A Torres
- Allergy Department, Fundación Jiménez Díaz, Madrid, Spain.
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18
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Leeper RJ, Ruiz CL, Chandler GA, Cooper GW, Bower DE, Fittinghoff DN, Hagen EC, Hollaway JR, McKenna IJ, McPherson LA, May MJ, Meeham BT, Nelson AJ, Perry TS, Porter JL, Robbins LL, Sinars DB, Torres JA, Ziegler LH. ZR neutron diagnostic suite. ACTA ACUST UNITED AC 2008. [DOI: 10.1088/1742-6596/112/3/032076] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Torres JA, Sastre J, de las Heras M, Cuesta J, Lombardero M, Ledesma A. IgE-mediated cereal allergy and latent celiac disease. J Investig Allergol Clin Immunol 2008; 18:412-414. [PMID: 18973112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Affiliation(s)
- J A Torres
- Allergy Department, Fundación Jiménez Díaz, Madrid, Spain.
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20
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Torres JA, Escudero C, Ibáñez MD, Ledesma A, Lombardero M. Milkflower cotoneaster (Cotoneaster lacteus): a new lipid transfer protein source from the Rosaceae family. J Investig Allergol Clin Immunol 2008; 18:227-228. [PMID: 18564640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Affiliation(s)
- J A Torres
- Allergy Department, Hospital Infantil Universitario Niño Jesús, Madrid, Spain.
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21
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González-Correa JA, Muñoz-Marín J, López-Villodres JA, Navas MD, Guerrero A, Torres JA, De La Cruz JP. Differences in the influence of the interaction between acetylsalicylic acid and salicylic acid on platelet function in whole blood and isolated platelets: influence of neutrophils. Pharmacol Res 2007; 56:168-74. [PMID: 17644353 DOI: 10.1016/j.phrs.2007.05.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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] [Received: 02/21/2007] [Revised: 05/18/2007] [Accepted: 05/21/2007] [Indexed: 11/23/2022]
Abstract
The aim of this study was to characterize the influence of the interaction between acetylsalicylic acid (ASA) and salicylic acid (SA) on the inhibition by ASA of platelet aggregation in platelets isolated from whole blood, and to determine whether leukocytes influence this pharmacological interaction. This in vitro study was done in human blood from which we prepared samples of whole blood, platelet-rich plasma (PRP), PRP plus mononuclear leukocytes, and PRP plus neutrophils. The variables recorded were maximum platelet aggregation intensity, thromboxane B2 (TxB2) production, and nitric oxide (NO) production (N=10 different samples in each type of experiment). Different concentrations of ASA and SA were incubated with all samples. In PRP, the concentration of ASA that inhibited maximum aggregation by 50% (IC50) (281+/-16microM) increased with increasing SA concentration to a maximum of more than 2mM when 500microM SA was used. In whole blood, the IC50 for ASA (24.9+/-1.2microM) decreased with decreasing SA concentrations to 7.9+/-0.8microM with 50microM SA and 15.6+/-0.9microM with 125microM SA, and increased to 46.2+/-2.6microM with 250microM SA and 96.3+/-7.2microM with 500microM SA. In experiments with PRP+neutrophils the IC50 of ASA increased in the presence of all concentrations of SA. The antagonistic interactions were also reflected in the changes in TxB2 production in all samples. In samples of neutrophils incubated with ASA, the curve for NO production was shifted to the right, a finding that paralleled the changes in platelet aggregation. In conclusion, the influence of the interaction between ASA and its metabolite SA on platelet aggregation difference depending on the type of sample, and was antagonistic in PRP but partially agonistic in whole blood. Nitric oxide synthesis showed an additive effect of the two compounds.
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Affiliation(s)
- J A González-Correa
- Department of Pharmacology and Therapeutics, School of Medicine, University of Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain
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22
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Vazquez-Landaverde PA, Torres JA, Qian MC. Quantification of trace volatile sulfur compounds in milk by solid-phase microextraction and gas chromatography-pulsed flame photometric detection. J Dairy Sci 2006; 89:2919-27. [PMID: 16840607 DOI: 10.3168/jds.s0022-0302(06)72564-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [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: 11/19/2022]
Abstract
Volatile sulfur compounds have been reported to be responsible for the sulfurous off-flavors generated during the thermal processing of milk; however, their analysis has been a challenge due to their high reactivity, high volatility, and low sensory threshold. In this study, reactive thiols were stabilized and the volatile sulfur compounds in milk were extracted by headspace solid-phase microextraction, and analyzed by gas chromatography and pulsed-flame photometric detection. Calibration curves for 7 sulfur-containing compounds were constructed in milk by the standard addition technique. Raw, pasteurized, and UHT milk samples with various fat contents were analyzed. Compared with raw and pasteurized samples, UHT milk contained substantially higher concentrations of hydrogen sulfide, methanethiol, carbon disulfide, dimethyl trisulfide, and di-methyl sulfoxide. The high odor activity values calculated for methanethiol and dimethyl trisulfide suggested that these 2 compounds, in addition to di-methyl sulfide reported in a previous study, could be the most important contributors to the sulfurous note in UHT milk.
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Affiliation(s)
- P A Vazquez-Landaverde
- Department of Food Science and Technology, Oregon State University, Corvallis 97331, USA
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Vazquez-Landaverde PA, Velazquez G, Torres JA, Qian MC. Quantitative Determination of Thermally Derived Off-Flavor Compounds in Milk Using Solid-Phase Microextraction and Gas Chromatography. J Dairy Sci 2005; 88:3764-72. [PMID: 16230682 DOI: 10.3168/jds.s0022-0302(05)73062-9] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.9] [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: 11/19/2022]
Abstract
Many volatile compounds generated during the thermal processing of milk have been associated with cooked, stale, and sulfurous notes in milk and are considered as off-flavor by most consumers. A headspace solid-phase microextraction (HS-SPME)/gas chromatographic technique for the quantitative analysis of thermally derived off-flavor compounds was developed in this study. The extraction temperature, time, and sample amount were optimized using a randomized 2(3) central composite rotatable design with 2 central replicates and 2 replicates in each factorial point along with response surface methodology. Calibration curves were constructed in milk using the standard addition technique, and then used to quantify 20 off-flavor compounds in raw, pasteurized, and UHT milk samples with various fat contents. The concentrations of these volatiles in raw and pasteurized milk samples were not significantly different. However, dimethyl sulfide, 2-hexanone, 2-heptanone, 2-nonanone, 2-undecanone, 2-methylpropanal, 3-methylbutanal, heptanal, and decanal were found at higher concentrations in UHT milk as compared with raw and pasteurized milk samples. In addition, the concentration of methyl ketones was greater in UHT milk with higher fat content. The calculated odor activity values suggested that 2,3-butanedione, 2-heptanone, 2-nonanone, 2-methylpropanal, 3-methylbutanal, nonanal, decanal, and dimethyl sulfide could be important contributors to the off-flavor of UHT milk. The HS-SPME technique developed in this study is accurate and relatively simple, and can be used for the quantification of thermally derived off-flavor compounds in milk.
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Affiliation(s)
- P A Vazquez-Landaverde
- Department of Food Science and Technology, Oregon State University, Corvallis 97331, USA
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24
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Stygar WA, Cuneo ME, Vesey RA, Ives HC, Mazarakis MG, Chandler GA, Fehl DL, Leeper RJ, Matzen MK, McDaniel DH, McGurn JS, McKenney JL, Muron DJ, Olson CL, Porter JL, Ramirez JJ, Seamen JF, Speas CS, Spielman RB, Struve KW, Torres JA, Waisman EM, Wagoner TC, Gilliland TL. Theoretical z -pinch scaling relations for thermonuclear-fusion experiments. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 72:026404. [PMID: 16196715 DOI: 10.1103/physreve.72.026404] [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: 06/21/2004] [Revised: 03/07/2005] [Indexed: 05/04/2023]
Abstract
We have developed wire-array z -pinch scaling relations for plasma-physics and inertial-confinement-fusion (ICF) experiments. The relations can be applied to the design of z -pinch accelerators for high-fusion-yield (approximately 0.4 GJ/shot) and inertial-fusion-energy (approximately 3 GJ/shot) research. We find that (delta(a)/delta(RT)) proportional (m/l)1/4 (Rgamma)(-1/2), where delta(a) is the imploding-sheath thickness of a wire-ablation-dominated pinch, delta(RT) is the sheath thickness of a Rayleigh-Taylor-dominated pinch, m is the total wire-array mass, l is the axial length of the array, R is the initial array radius, and gamma is a dimensionless functional of the shape of the current pulse that drives the pinch implosion. When the product Rgamma is held constant the sheath thickness is, at sufficiently large values of m/l, determined primarily by wire ablation. For an ablation-dominated pinch, we estimate that the peak radiated x-ray power P(r) proportional (I/tau(i))(3/2)Rlphigamma, where I is the peak pinch current, tau(i) is the pinch implosion time, and phi is a dimensionless functional of the current-pulse shape. This scaling relation is consistent with experiment when 13 MA < or = I < or = 20 MA, 93 ns < or = tau(i) < or = 169 ns, 10 mm < or = R < or = 20 mm, 10 mm < or = l < or = 20 mm, and 2.0 mg/cm < or = m/l < or = 7.3 mg/cm. Assuming an ablation-dominated pinch and that Rlphigamma is held constant, we find that the x-ray-power efficiency eta(x) congruent to P(r)/P(a) of a coupled pinch-accelerator system is proportional to (tau(i)P(r)(7/9 ))(-1), where P(a) is the peak accelerator power. The pinch current and accelerator power required to achieve a given value of P(r) are proportional to tau(i), and the requisite accelerator energy E(a) is proportional to tau2(i). These results suggest that the performance of an ablation-dominated pinch, and the efficiency of a coupled pinch-accelerator system, can be improved substantially by decreasing the implosion time tau(i). For an accelerator coupled to a double-pinch-driven hohlraum that drives the implosion of an ICF fuel capsule, we find that the accelerator power and energy required to achieve high-yield fusion scale as tau(i)0.36 and tau(i)1.36, respectively. Thus the accelerator requirements decrease as the implosion time is decreased. However, the x-ray-power and thermonuclear-yield efficiencies of such a coupled system increase with tau(i). We also find that increasing the anode-cathode gap of the pinch from 2 to 4 mm increases the requisite values of P(a) and E(a) by as much as a factor of 2.
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Affiliation(s)
- W A Stygar
- Sandia National Laboratories, Albuquerque, New Mexico 87185-1196, USA
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25
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Cuneo ME, Waisman EM, Lebedev SV, Chittenden JP, Stygar WA, Chandler GA, Vesey RA, Yu EP, Nash TJ, Bliss DE, Sarkisov GS, Wagoner TC, Bennett GR, Sinars DB, Porter JL, Simpson WW, Ruggles LE, Wenger DF, Garasi CJ, Oliver BV, Aragon RA, Fowler WE, Hettrick MC, Idzorek GC, Johnson D, Keller K, Lazier SE, McGurn JS, Mehlhorn TA, Moore T, Nielsen DS, Pyle J, Speas S, Struve KW, Torres JA. Characteristics and scaling of tungsten-wire-array z -pinch implosion dynamics at 20 MA. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 71:046406. [PMID: 15903793 DOI: 10.1103/physreve.71.046406] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2003] [Revised: 05/14/2004] [Indexed: 05/02/2023]
Abstract
We present observations for 20-MA wire-array z pinches of an extended wire ablation period of 57%+/-3% of the stagnation time of the array and non-thin-shell implosion trajectories. These experiments were performed with 20-mm-diam wire arrays used for the double- z -pinch inertial confinement fusion experiments [M. E. Cuneo, Phys. Rev. Lett. 88, 215004 (2002)] on the Z accelerator [R. B. Spielman, Phys. Plasmas 5, 2105 (1998)]. This array has the smallest wire-wire gaps typically used at 20 MA (209 microm ). The extended ablation period for this array indicates that two-dimensional (r-z) thin-shell implosion models that implicitly assume wire ablation and wire-to-wire merger into a shell on a rapid time scale compared to wire acceleration are fundamentally incorrect or incomplete for high-wire-number, massive (>2 mg/cm) , single, tungsten wire arrays. In contrast to earlier work where the wire array accelerated from its initial position at approximately 80% of the stagnation time, our results show that very late acceleration is not a universal aspect of wire array implosions. We also varied the ablation period between 46%+/-2% and 71%+/-3% of the stagnation time, for the first time, by scaling the array diameter between 40 mm (at a wire-wire gap of 524 mum ) and 12 mm (at a wire-wire gap of 209 microm ), at a constant stagnation time of 100+/-6 ns . The deviation of the wire-array trajectory from that of a thin shell scales inversely with the ablation rate per unit mass: f(m) proportional[dm(ablate)/dt]/m(array). The convergence ratio of the effective position of the current at peak x-ray power is approximately 3.6+/-0.6:1 , much less than the > or = 10:1 typically inferred from x-ray pinhole camera measurements of the brightest emitting regions on axis, at peak x-ray power. The trailing mass at the array edge early in the implosion appears to produce wings on the pinch mass profile at stagnation that reduces the rate of compression of the pinch. The observation of precursor pinch formation, trailing mass, and trailing current indicates that all the mass and current do not assemble simultaneously on axis. Precursor and trailing implosions appear to impact the efficiency of the conversion of current (driver energy) to x rays. An instability with the character of an m = 0 sausage grows rapidly on axis at stagnation, during the rise time of pinch power. Just after peak power, a mild m = 1 kink instability of the pinch occurs which is correlated with the higher compression ratio of the pinch after peak power and the decrease of the power pulse. Understanding these three-dimensional, discrete-wire implosion characteristics is critical in order to efficiently scale wire arrays to higher currents and powers for fusion applications.
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Affiliation(s)
- M E Cuneo
- Pulsed Power Sciences Center, Sandia National Laboratories, Albuquerque, New Mexico 87195-1193, USA.
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26
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Serrano J, Velazquez G, Lopetcharat K, Ramírez JA, Torres JA. Effect of Moderate Pressure Treatments on Microstructure, Texture, and Sensory Properties of Stirred-Curd Cheddar Shreds. J Dairy Sci 2004; 87:3172-82. [PMID: 15377595 DOI: 10.3168/jds.s0022-0302(04)73452-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [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: 11/19/2022]
Abstract
A moderate high-pressure processing (HPP) treatment is proposed to accelerate the shredability of Cheddar cheese. High pressure processing (345 and 483 MPa for 3 and 7 min) applied to unripened (1 d old) stirred-curd Cheddar cheese yielded microstructure changes that differed with pressure level and processing time. Untreated and pressure-treated cheese shredded at d 27 and 1, respectively, shared similar visual and tactile sensory properties. The moderate (345 MPa) and the higher (483 MPa) pressure treatments reduced the presence of crumbles, increased mean shred particle length, improved length uniformity, and enhanced surface smoothness in shreds produced from unripened cheese. High-pressure processing treatments did not affect the mechanical properties of ripened cheese or the proteolytic susceptibility of milk protein. It was concluded that a moderate HPP treatment could allow processors to shred Cheddar cheese immediately after block cooling, reducing refrigerated storage costs, with expected savings of over 15 US dollars/1000 lb cheese, and allowing fewer steps in the handling of cheese blocks produced for shredding.
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Affiliation(s)
- J Serrano
- Food Process Engineering Group, Department of Food Science and Technology, Oregon State University, 100 Wiegand Hall, Corvallis 97331-6602, USA
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27
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Stygar WA, Ives HC, Fehl DL, Cuneo ME, Mazarakis MG, Bailey JE, Bennett GR, Bliss DE, Chandler GA, Leeper RJ, Matzen MK, McDaniel DH, McGurn JS, McKenney JL, Mix LP, Muron DJ, Porter JL, Ramirez JJ, Ruggles LE, Seamen JF, Simpson WW, Speas CS, Spielman RB, Struve KW, Torres JA, Vesey RA, Wagoner TC, Gilliland TL, Horry ML, Jobe DO, Lazier SE, Mills JA, Mulville TD, Pyle JH, Romero TM, Seamen JJ, Smelser RM. X-ray emission from z pinches at 10 7 A: current scaling, gap closure, and shot-to-shot fluctuations. Phys Rev E Stat Nonlin Soft Matter Phys 2004; 69:046403. [PMID: 15169102 DOI: 10.1103/physreve.69.046403] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2003] [Indexed: 05/24/2023]
Abstract
We have measured the x-ray power and energy radiated by a tungsten-wire-array z pinch as a function of the peak pinch current and the width of the anode-cathode gap at the base of the pinch. The measurements were performed at 13- and 19-MA currents and 1-, 2-, 3-, and 4-mm gaps. The wire material, number of wires, wire-array diameter, wire-array length, wire-array-electrode design, normalized-pinch-current time history, implosion time, and diagnostic package were held constant for the experiments. To keep the implosion time constant, the mass of the array was increased as I2 (i.e., the diameter of each wire was increased as I), where I is the peak pinch current. At 19 MA, the mass of the 300-wire 20-mm-diam 10-mm-length array was 5.9 mg. For the configuration studied, we find that to eliminate the effects of gap closure on the radiated energy, the width of the gap must be increased approximately as I. For shots unaffected by gap closure, we find that the peak radiated x-ray power P(r) proportional to I1.24+/-0.18, the total radiated x-ray energy E(r) proportional to I1.73+/-0.18, the x-ray-power rise time tau(r) proportional to I0.39+/-0.34, and the x-ray-power pulse width tau(w) proportional to demonstrate that the internal energy and radiative opacity of the pinch are not responsible for the observed subquadratic power scaling. Heuristic wire-ablation arguments suggest that quadratic power scaling will be achieved if the implosion time tau(i) is scaled as I(-1/3). The measured 1sigma shot-to-shot fluctuations in P(r), E(r), tau(r), tau(w), and tau(i) are approximately 12%, 9%, 26%, 9%, and 2%, respectively, assuming that the fluctuations are independent of I. These variations are for one-half of the pinch. If the half observed radiates in a manner that is statistically independent of the other half, the variations are a factor of 2(1/2) less for the entire pinch. We calculate the effect that shot-to-shot fluctuations of a single pinch would have on the shot-success probability of the double-pinch inertial-confinement-fusion driver proposed by Hammer et al. [Phys. Plasmas 6, 2129 (1999)]. We find that on a given shot, the probability that two independent pinches would radiate the same peak power to within a factor of 1+/-alpha (where 0< or =alpha<<1) is equal to erf(alpha/2sigma), where sigma is the 1sigma fractional variation of the peak power radiated by a single pinch. Assuming alpha must be < or =7% to achieve adequate odd-Legendre-mode radiation symmetry for thermonuclear-fusion experiments, sigma must be <3% for the shot-success probability to be > or =90%. The observed (12/2(1/2))%=8.5% fluctuation in P(r) would provide adequate symmetry on 44% of the shots. We propose that three-dimensional radiative-magnetohydrodynamic simulations be performed to quantify the sensitivity of the x-ray emission to various initial conditions, and to determine whether an imploding z pinch is a spatiotemporal chaotic system.
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Affiliation(s)
- W A Stygar
- Sandia National Laboratories, Albuquerque, New Mexico 87185-1196, USA
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Abstract
In group-living animals, mutual policing to suppress reproduction is an important mechanism in the resolution of conflict between selfish group members and the group as a whole. In societies of bees, ants, and wasps, policing against the production of males by other workers is expected when egg laying by workers decreases the average inclusive fitness of individual group members. This may result (i) from the relatedness of workers being lower to worker than to queen-derived males or (ii) from a lowered overall colony efficiency. Whereas good evidence exists for policing behavior caused by genetic conflicts, policing caused by efficiency factors has not been demonstrated. We investigated the regulation of reproduction in the ant Platythyrea punctata, a species in which colonies are clones because workers are capable of producing female offspring by thelytokous parthenogenesis. Reproductive conflicts resulting from differences in genetic relatedness are therefore not expected, but uncontrolled reproduction by all workers could lead to the destruction of sociality. Here we show that worker policing by aggressive attacks against additionally reproducing workers keeps the number of reproducing workers low. Furthermore, through experimental manipulation of the number of brood items per colony, we show that worker policing can enhance group efficiency.
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Affiliation(s)
- A Hartmann
- Department of Biology I, University of Regensburg, Universitätsstrasse 31, 93040 Regensburg, Germany.
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Cuneo ME, Vesey RA, Porter JL, Bennett GR, Hanson DL, Ruggles LE, Simpson WW, Idzorek GC, Stygar WA, Hammer JH, Seamen JJ, Torres JA, McGurn JS, Green RM. Double Z-pinch hohlraum drive with excellent temperature balance for symmetric inertial confinement fusion capsule implosions. Phys Rev Lett 2002; 88:215004. [PMID: 12059481 DOI: 10.1103/physrevlett.88.215004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2002] [Indexed: 05/23/2023]
Abstract
A double Z pinch driving a cylindrical secondary hohlraum from each end has been developed which can indirectly drive intertial confinement fusion capsule implosions with time-averaged radiation fields uniform to 2%-4%. 2D time-dependent view factor and 2D radiation hydrodynamic simulations using the measured primary hohlraum temperatures show that capsule convergence ratios of at least 10 with average distortions from sphericity of <Delta r>/r<or=30% are possible on the Z accelerator and may meet radiation symmetry requirements for scaling to fusion yields of >200 MJ.
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Affiliation(s)
- M E Cuneo
- Sandia National Laboratory, P.O. Box 5800, Albuquerque, New Mexico 87185-1193, USA.
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Aguilera PA, Frenich AG, Torres JA, Castro H, Martinez Vidal JL, Canton M. Application of the Kohonen neural network in coastal water management: methodological development for the assessment and prediction of water quality. Water Res 2001; 35:4053-4062. [PMID: 11791834 DOI: 10.1016/s0043-1354(01)00151-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [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
Kohonen neural network (KNN) was applied to nutrient data (ammonia, nitrite, nitrate and phosphate) taken from coastal waters in a Spanish tourist area. The activation maps obtained were not sufficient to evaluate and predict the trophic status of coastal waters. To achieve this aim, a new methodology is proposed which uses as its starting point the activation maps obtained from KNN. Firstly, to evaluate the trophic status of the coastal waters, it consists of the development of a quadrat system which enables a better classification than the traditional classification based simply on standardized data. The new classification allows clear differentiation of water quality within the mesotrophic band. Secondly, and in order to use the activation maps as predictive tools, the trophic classification, obtained from activation maps, was transposed onto new activation maps. To do this, the activation maps of the sampling points which defined each trophic group were superimposed. To avoid unnecessary complexity and to facilitate the process, this superimposition was undertaken only where the frequency exceeded 0.05. In this way, four frequency maps related to the trophic status of coastal waters (potentially eutrophic, high mesotrophic, low mesotrophic and oligotrophic) were obtained. There was no loss of relevant information in the new maps thus obtained. These frequency maps served as the basis for the successful prediction of the trophic status of random samples of coastal waters. This methodology, based on KNN, is proposed as a tool to aid the decision-making in coastal water quality management.
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Affiliation(s)
- P A Aguilera
- Department of Ecology, University of Almeria, Spain.
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Abstract
Chitosan-Polyanion (Chi-Pol) complexes were used as coagulating agents for treating Cheddar cheese whey. Complexation and coagulation time played a significant role in adsorption, whereas polymer concentration was significant only for chitosan-alginate complexes. Complexes of chitosan with alginate (ALG), pectin (PEC), and carrageenan (CAR) used at 30 mg complex/L whey showed turbidity reductions of 40-43% and 65-72% after 1 and 39 h, respectively. At 10 mg/L, the percent reduction in turbidity after 1 and 39 h were 35-39% and 61-64%, respectively. No significant differences in turbidity reduction (P > 0.05) were observed when using complexes at different Chi-Pol monomeric mixing ratios (MR) except for Chi-Alg at 30 mg/L, wherein reduction at 0.2 was higher than 0.8 MR. Also, UV-vis spectroscopy suggested the preference of this complex for the absorption of specific whey protein fractions. This study successfully demonstrated the effectiveness of Chi-Pol complexes in flocculation of suspended solid wastes in cheese whey with over 70% protein recovery.
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Affiliation(s)
- V D Savant
- Department of Food Science & Technology, Oregon State University, Corvallis, Oregon 97331, USA
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Torres JA, Nealey PF, de Pablo JJ. Molecular simulation of ultrathin polymeric films near the glass transition. Phys Rev Lett 2000; 85:3221-3224. [PMID: 11019306 DOI: 10.1103/physrevlett.85.3221] [Citation(s) in RCA: 248] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/1999] [Indexed: 05/23/2023]
Abstract
Properties such as the glass transition temperature ( T(g)) and the diffusion coefficient of ultrathin polymeric films are shown to depend on the dimensions of the system. In this work, a hard-sphere molecular dynamics methodology has been applied to simulate such systems. We investigate the influence that substrates have on the behavior of thin polymer films; we report evidence suggesting that, depending on the strength of substrate-polymer interactions, the glass transition temperature for a thin film can be significantly lower or higher than that of the bulk.
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Affiliation(s)
- J A Torres
- Department of Chemical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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Salazar EL, Torres JA, Avila A, Andrade A. Hyperplastic changes and receptor status in the breast tissue of bodybuilders under anabolic-androgenic steroid stimulation. Arch Androl 2000; 45:1-7. [PMID: 10959495 DOI: 10.1080/014850100409945] [Citation(s) in RCA: 2] [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: 10/16/2022]
Abstract
Anabolic androgenic steroids (AAS) are misused by athletes to improve their physical performance. AAS with similar groups and configuration indicate that testosterone is the base of this ability to stimulate anabolic activity. The effect of these compounds on the breast tissue of males that consume them is a confirmation of its metabolic pathway. To confirm its hormonal effects, the status of estradiol and progesterone receptors (ER, PgR) status was determined in cytoplasmic and nuclear fractions (HRc, HRn) of 8 premalignant breast tissues from 8 bodybuilders (aged 21 to 45 years) under AAS stimulation. The control group included 5 males with benign disorders of the breast, but not due to AAS administration. The concentrations of ERc and ERn were significantly higher (p < .05) in males under AAS stimulation than in males without these. The concentrations of PgRc and PgRn do not differ between these two groups (p > .05) The benign breast disease is remarkably similar in female and male patients, suggesting a common origin. In the same way, the measurement of both HRc and HRn is necessary to accurately report receptor concentration.
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Affiliation(s)
- E L Salazar
- Medical Research Reproductive Biology Unit, Obstetrics and Gynecology Hospital, IMSS, Mexico City, Mexico.
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Tabengwa EM, Abou-Agag LH, Benza RL, Torres JA, Aikens ML, Booyse FM. Ethanol-induced up-regulation of candidate plasminogen receptor annexin II in cultured human endothelial cells. Alcohol Clin Exp Res 2000; 24:754-61. [PMID: 10888061] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
INTRODUCTION Epidemiological studies indicate that moderate alcohol consumption reduces the risk for coronary heart disease and that this cardioprotective benefit may be mediated, in part, by increased fibrinolysis. Endothelial cells (ECs) synthesize plasminogen activators, tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA), receptors for plasminogen activators, and a receptor for plasminogen, annexin II (Ann-II). These receptors localize and facilitate receptor-bound plasminogen activator-mediated conversion of receptor-bound plasminogen to receptor-bound plasmin on the EC surface, which results in the regulated expression of surface-localized EC fibrinolytic activity. Ethanol is a systemic factor that affects these components, which increases EC fibrinolysis and hence reduces the risk for thrombosis, coronary heart disease, and myocardial infarction (MI). METHODS This study was carried out to determine whether low ethanol (0.1% v/v) increased plasminogen receptor, Ann-II antigen (western blot), messenger ribonucleic acid (mRNA) (reverse transcription polymerase chain reaction; RT-PCR) expression, activity (ligand binding/Scatchard analysis), and hence fibrinolysis (plasmin generation) in cultured human ECs. RESULTS Plasminogen receptor activity increased approximately 2-fold (2.5 vs. 5.6 x 10(6) sites/cell), as evidenced by increased 125I-labeled Glu-plasminogen ligand binding/Scatchard analysis. In addition, western blot analyses indicated an increase in Ann-II antigen, and mRNA levels increased approximately 2-fold (RT-PCR). This increase in Ann-II expression was concomitant with approximately 2- to 3-fold sustained increase (approximately 24 hr) in surface-localized EC fibrinolytic activity. Nuclear transcription run-on assays showed an approximately 5- to 6-fold increase in new 32P-labeled Ann-II mRNA levels, compared with controls (no ethanol). CONCLUSIONS These results demonstrated that low ethanol increased Ann-II antigen/mRNA levels and up-regulated Ann-II gene expression at the transcriptional level. The results further identify and define the contribution and role of the plasminogen receptor, Ann-II, in the ethanol-induced mechanism of increased EC fibrinolysis that may underlie and contribute, in part, to the cardioprotective benefit associated with moderate alcohol consumption.
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Affiliation(s)
- E M Tabengwa
- Department of Medicine, University of Alabama at Birmingham, 35294-2170, USA
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35
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Affiliation(s)
- J A Torres
- Department of Orthopedic Surgery, University of Florida, Gainesville 32610, USA
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Jones TH, Flournoy RC, Torres JA, Snelling RR, Spande TF, Garraffo HM. 3-methyl-4-phenylpyrrole from the ants Anochetus kempfi and Anochetus mayri. J Nat Prod 1999; 62:1343-1345. [PMID: 10514333 DOI: 10.1021/np990245t] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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
The cephalic extracts of the ant Anochetus kempfi were found to contain 2,5-dimethyl-3-isoamylpyrazine (1) and 3-methyl-4-phenylpyrrole (2). The structures of these compounds were established from their spectral data and by comparison with synthetic samples. This is the first report of a phenylpyrrole found in an insect and only the third report of a pyrrole from ants.
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Affiliation(s)
- T H Jones
- Department of Chemistry, Virginia Military Institute, Lexington, Virginia 24450, USA.
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Hernández S, Lanz H, Rodríguez MH, Torres JA, Martínez-Palomo A, Tsutsumi V. Morphological and cytochemical characterization of female Anopheles albimanus (Diptera: Culicidae) hemocytes. J Med Entomol 1999; 36:426-434. [PMID: 10467768 DOI: 10.1093/jmedent/36.4.426] [Citation(s) in RCA: 29] [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] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Hemocytes of 2- to 3-d-old female Anopheles albimanus Wiedemann are described by morphology, cytochemistry, and functional criteria. Supplemented Grace's insect medium in a modified Foley's perfusion method was used to obtain hemolymph from An. albimanus. Morphological analysis indicated 3 types of hemocytes were present, prohemocytes, plasmatocytes, and granular cells. Prohemocytes were small round cells with a high nuclear/cytoplasmic ratio. Plasmatocytes were the most abundant cell types in the hemolymph, and appeared as small to large and spindle-shaped cells with round or elongate nucleus, variable number of vacuoles, small granules, and pseudopodia. Granular cells were small to large and round with a large number of cytoplasmic granules, vacuoles, and numerous filopodia. Ultrastructurally, prohemocytes were undifferentiated with abundant free ribosomes and with few small electron-dense granules. Plasmatocytes were rich in mitochondria, rough endoplasmic reticulum, free ribosomes, small electron-dense granules, numerous peripheral vacuoles and with an important organelle polarization. Granular cells contained numerous large electron-dense granular inclusions and vacuoles. Cytochemical studies showed that plasmatocytes and granular cells have cationic bactericidal proteins. Only granular cells showed phenoloxidase and probably lysosomal activities. In vitro functional studies demonstrated that both plasmatocytes and granular cells were able to attach to glass slides, and only plasmatocyte had phagocytic activity and motility. These results characterize the hemocytes of An. albimanus and suggest that plasmatocytes and granular cells may have a role in defense responses to foreign organisms.
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Affiliation(s)
- S Hernández
- Departamento de Patología Experimental, Centro de Investigación y de Estudios Avanzados, I.P.N, Mexico D.F., Mexico
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Spande TF, Jain P, Garraffo HM, Pannell LK, Yeh HJC, Daly JW, Fukumoto S, Imamura K, Tokuyama T, Torres JA, Snelling RR, Jones TH. Occurrence and significance of decahydroquinolines from dendrobatid poison frogs and a myrmicine ant: use of 1H and 13C NMR in their conformational analysis. J Nat Prod 1999; 62:5-21. [PMID: 9917275 DOI: 10.1021/np980298v] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Structures for 2,5-disubstituted decahydroquinolines (DHQs) are reported for the two diastereomeric pairs cis-275B (14) and cis-275B' (15) and 5-epi-trans-269AB (18) and trans-269AB (19), all isolated from skin extracts of dendrobatid frogs, and for 5-epi-cis-275B' (16) and 5-epi-trans-275B (17) found in the extracts of virgin queens of a myrmicine ant [Solenopsis (Diplorhoptrum) azteca]. Detection of such DHQs in an ant, their first reported occurrence, strengthens a dietary hypothesis for the origin of the approximately 30 DHQs that have been detected in extracts of frog skin. NMR data on the two conformers of cis-decahydroquinoline permit assignment of ring conformations and stereochemistry to cis-DHQs of the "N-endo" type or the "N-exo" type. These conformations are also assigned on whether H-8a is equatorial or axial as determined with E-COSY or 1D-HOHAHA spectra.
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Affiliation(s)
- TF Spande
- Department of Chemistry, Virginia Military Institute, Lexington, Virginia 24450-0304, USA
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Boisbouvier J, Prochnicka-Chalufour A, Nieto AR, Torres JA, Nanard N, Rodriguez MH, Possani LD, Delepierre M. Structural information on a cecropin-like synthetic peptide, Shiva-3 toxic to the sporogonic development of Plasmodium berghei. Eur J Biochem 1998; 257:263-73. [PMID: 9799128 DOI: 10.1046/j.1432-1327.1998.2570263.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study is a contribution towards the understanding of the mode of action of Shiva-3 and more generally that of cecropin-like peptides. Structural information on Shiva-3 (a cecropin-like synthetic peptide) in water and in a membrane-mimicking environment (trifluoroethanol alcohol, SDS) were obtained using analytical centrifugation, CD and NMR spectroscopies. A total of 20 converged structures were retained on the basis of 197 non-redundant experimental constraints, including 166 distance constraints from the nuclear Overhauser effect measurements and 31 dihedral angle restraints derived from the purged COSY experiments. Some results obtained in presence of SDS are also presented. The toxic effects of the peptides obtained by cleavage (trypsin and lysine-C hydrolysis) of Shiva-3 on Escherichia coli and on Plasmodium berghei sporogonic stages are reported. Biological effects are discussed in relation to the calculated structure. The antiparasite activity and the low mosquito toxicity of Shiva-3 make this peptide a good candidate for genetic transformation of mosquito vectors which warrants further studies aimed at the improvement of the molecule.
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Affiliation(s)
- J Boisbouvier
- Laboratoire de Résonance Magnétique Nucléaire, Institut Pasteur, CNRS URA 1129, Paris, France
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Grenett HE, Aikens ML, Torres JA, Demissie S, Tabengwa EM, Davis GC, Booyse FM. Ethanol transcriptionally upregulates t-PA and u-PA gene expression in cultured human endothelial cells. Alcohol Clin Exp Res 1998; 22:849-53. [PMID: 9660311] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Epidemiological studies have suggested that moderate alcohol consumption reduces the risk of cardiovascular mortality. This cardioprotective benefit may be mediated, in part, by promoting fibrinolysis through changes in fibrinolytic components and/or activity, resulting in the decreased risk for thrombosis, coronary artery disease, and eventual myocardial infarction. Endothelial cells (ECs) play a pivotal role in maintaining normal hemostasis by regulating fibrinolysis through the synthesis of plasminogen activators (PAs), tissue-type plasminogen activator (t-PA), and urokinase-type plasminogen activator (u-PA). The studies described herein were conducted to determine whether a single brief preincubation (1 hr, 37 degrees C) of cultured human umbilical vein ECs (HUVECs) with low ethanol (0.1%, v/v), will upregulate t-PA and/or u-PA gene expression at the transcriptional level, using a combination of nuclear transcription run-on assays and transient transfections of cultured HUVECs with the pPA/luc promoter constructs. Nuclear run-on assays showed approximately 2- to 3-fold and approximately 6- to 7-fold increase in the transcription of new t-PA and u-PA mRNAs, respectively. In addition, transient transfections of cultured HUVECs with the pt-PA363/luc and pu-PA236/luc promoter constructs, using lipofectamine, demonstrated approximately 4- to 6-fold and approximately 6- to 9-fold increase in luciferase activity for t-PA and u-PA, respectively. These combined results demonstrate that low ethanol transcriptionally upregulates both t-PA and u-PA gene expression in cultured HUVECs and provides a molecular basis for the ethanol-induced increase in EC-mediated fibrinolytic activity that may underlie and contribute, in part, to the cardioprotective benefit associated with moderate alcohol consumption.
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Affiliation(s)
- H E Grenett
- Department of Medicine, University of Alabama at Birmingham, 35294-2170, USA
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García-Martín A, Torres JA, Sáenz JJ. Finite size corrections to the conductance of ballistic wires. Phys Rev B Condens Matter 1996; 54:13448-13451. [PMID: 9985244 DOI: 10.1103/physrevb.54.13448] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Torres JA, Sáenz JJ. Conductance and Mechanical Properties of Atomic-Size Metallic Contacts: A Simple Model. Phys Rev Lett 1996; 77:2245-2248. [PMID: 10061895 DOI: 10.1103/physrevlett.77.2245] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
In contrast to other ants in the genus Monomorium that produce cyclic amines, extracts of Monomorium floricola contain (Z)-7-tetradecenylamine (1) and (Z)-9-tetradecenylamine (2). The structures of these compounds were established from their spectral data and by comparison with synthetic 2.
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Affiliation(s)
- T H Jones
- Department of Chemistry, Virginia Military Institute, Lexington 24450, USA
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44
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Rodríguez MDC, Torres JA, Zlotnik H. Investigation of the temporal humoral immune response in a murine model of actinomycetoma. P R Health Sci J 1996; 15:91-5. [PMID: 8936612] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The murine model of actinomycetoma offers the potential of studying many unknown aspects of this infection. In this work, the model was used to investigate the temporal humoral immune response to actinomycetoma agents. Groups of 7- to 9-week-old female BALB/c mice were inoculated in one of the hind footpads with one of four different Nocardia strains. To mimic the constant exposure of infected humans to the virulent soil inhabiting agents, a second injection consisting of live nocardiae in incomplete Freund's adjuvant was administered five months after the first one. Murine serum samples were collected throughout the study and their IgM and IgM titers were determined by ELISA and the Western blot assay. The results obtained indicate that the ELISA titers increased as the infection progressed and this correlated with a greater number of antigen bands being recognized in the blots. Overall, however, the ELISA titers were lower for the N. brasiliensis infected mice than those of the N. asteroides ones. This observation may be indicative of an immunosuppressive state and is worthy of further investigation.
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Affiliation(s)
- M del C Rodríguez
- Department of Microbiology and Medical Zoology, University of Puerto Rico School of Medicine, San Juan
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Rodriguez MC, Zamudio F, Torres JA, Gonzalez-Ceron L, Possani LD, Rodriguez MH. Effect of a cecropin-like synthetic peptide (Shiva-3) on the sporogonic development of Plasmodium berghei. Exp Parasitol 1995; 80:596-604. [PMID: 7758540 DOI: 10.1006/expr.1995.1075] [Citation(s) in RCA: 56] [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: 01/27/2023]
Abstract
The effect of a synthetic cecropin-like peptide, Shiva-3, on in vitro ookinete development and on the early sporogonic stages of Plasmodium berghei in the midgut of Anopheles albimanus was investigated. Peptide concentrations of 75 and 100 microM were effective (P < 0.05) in reducing ookinete production and the number of infected mosquitoes in almost all experiments. These peptide concentrations in the midgut were not toxic for the survival of the mosquitoes. Complete inhibition was obtained if 100 microM Shiva-3 was applied in the first 8 hr of parasite development. The deleterious effect of the peptide on the parasite was effective after exposure for as short as 50 sec and the permanence of free peptide in the mosquito midgut was estimated to be of a minimum of 5 min. These observations indicate the possibility of using Shiva-like peptide genes to engineering malaria-resistant vectors as an alternative in malaria control strategies.
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Affiliation(s)
- M C Rodriguez
- Centro de Investigación de Paludismo, Ministry of Health, Tapachula, Chiapas, Mexico
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Torres JA, Bouzas J, Kirby C, Almonacid Merino SF, Kantt CA, Simpson R, Banga JR. Time-temperature effects on microbial, chemical and sensory changes during cooling and aging of cheddar cheese. Adv Exp Med Biol 1995; 367:123-59. [PMID: 7572359 DOI: 10.1007/978-1-4615-1913-3_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- J A Torres
- Department of Food Science and Technology, Oregon State University, Corvallis 97331-6602, USA
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Torres JA, Sponseller P, Kim TS, Kuncl RW, Crawford T. Radiographic and histological characterization of Tc/tw5 mice: an animal model of lumbosacral agenesis/myelomeningocele. Dev Med Child Neurol 1994; 36:698-706. [PMID: 8050623 DOI: 10.1111/j.1469-8749.1994.tb11912.x] [Citation(s) in RCA: 2] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Twenty-five Tc/tw5 and 12 control mice were killed at different ages and radiographically and histologically examined. In addition, histochemical analysis was performed on muscles from four mutant and one control mouse. All Tc/tw5 mice were tailless and had a fluid-filled lumbar myelomeningocele. Radiographically, most animals had six instead of 10 lumbosacral vertebrae. Vertebral anomalies were common. The spinal cord was grossly abnormal: at the level of the plaque, it was replaced by patches of neural tissue intermingled with connective tissue and muscle. Affected skeletal muscles had small myofibers with centrally placed nuclei consistent with arrest of development at the myotubular stage secondary to denervation in early embryonic life. Abnormal nerves were smaller and had fewer axons. Tc/tw5 mice show features of neural tube and notochord dysplasia. These mutant mice may be useful as animal models of lumbosacral agenesis and myelomeningocele.
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Affiliation(s)
- J A Torres
- Johns Hopkins Outpatient Center, Baltimore, MD 21287-0882
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Torres JA, Pascual JI, Sáenz JJ. Theory of conduction through narrow constrictions in a three-dimensional electron gas. Phys Rev B Condens Matter 1994; 49:16581-16584. [PMID: 10010814 DOI: 10.1103/physrevb.49.16581] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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49
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Chan AS, Rodríguez MH, Torres JA, Rodríguez MDC, Villarreal C. Susceptibility of three laboratory strains of Anopheles albimanus (Diptera: Culicidae) to coindigenous Plasmodium vivax in southern Mexico. J Med Entomol 1994; 31:400-403. [PMID: 8057314 DOI: 10.1093/jmedent/31.3.400] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Three morphologically different pupal phenotypes (green, striped, brown) were selected from a parent strain of Anopheles albimanus Wiedemann collected from the Suchiate region in the state of Chiapas, Mexico. Significant differences in susceptibility to coindigenous Plasmodium vivax Grassi & Feletti were observed when striped was compared with the parent colony as well as with brown and with green phenotypes. Differences in susceptibility were not significant between the other phenotypes and the parent colony.
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Affiliation(s)
- A S Chan
- Centro de Investigación de Paludismo, Tapachula, Chiapas, Mexico
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Kantt CA, Torres JA. Growth Inhibition by Glucose Oxidase of Selected Organisms Associated With the Microbial Spoilage of Shrimp ( Pandalus jordani ): In Vitro Model Studies. J Food Prot 1993; 56:147-152. [PMID: 31084108 DOI: 10.4315/0362-028x-56.2.147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The effect of glucose oxidase (GOX)-catalase with different GOX-catalase ratios and of the Chemicals produced by GOX, gluconic acid and hydrogen peroxide, were evaluated on four microorganisms usually present in shrimp. Growth inhibition was independent of the enzyme ratio within the limits tested. Hydrogen peroxide inhibited Pseudomonas fluorescens , Hansenula polymorpha and Acinetobacter calcoaceticum . Only Corynebacter aquaticum was inhibited by gluconic acid but was not affected by hydrogen peroxide.
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Affiliation(s)
- C A Kantt
- Currently a Gradúate Student at University of Illinois, Urbana
| | - J A Torres
- Food Process Engineering Group, Department of Food Science and Technology, Oregon State University, Corvallis, Oregon 97331-6602
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