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Sample records for white seabream diplodus

  1. Allozyme and mtDNA variation of white seabream Diplodus sargus ...

    African Journals Online (AJOL)

    These results can be explained by the chaotic genetic patchiness hypothesis. In contrast, the mtDNA data indicated genetic homogeneity among localities showing the absence of structure in white seabream populations across the Siculo-Tunisian Strait. Historical demography of this species suggests that it has undergone ...

  2. Morphometric, molecular and ecological analyses of the parasites of the sharpsnout seabream Diplodus puntazzo Cetti (Sparidae) from the Spanish Mediterranean: implications for aquaculture.

    Science.gov (United States)

    Sánchez-García, N; Ahuir-Baraja, A E; Raga, J A; Montero, F E

    2015-03-01

    One of the fish species with the highest potential for aquaculture is the sharpsnout seabream, Diplodus puntazzo Cetti. Among other aspects, the development of new fish cultures requires studies of potential pathogens that may compromise survival of the fish in captivity. Moreover, both cultured and wild fish can act as sources or reservoirs of pathogens which may negatively affect other well-established cultures. We have studied the parasite fauna of the wild sharpsnout seabream, and monitored the survival of the parasites in culture conditions. The sharpsnout seabream was sampled from two different Spanish localities and examined for parasites. Additionally, 20 fish were maintained in captivity. Ten of them were examined for parasites after a period of 10 days and a further ten fish after another 10 days. All fish were parasitized with at least four species, with 19 parasite species being identified, seven of which were recorded for the first time in the sharpsnout seabream. These included Microcotyle sp., Magnibursatus bartolii, Steringotrema pagelli, Galactosomum sp., Cardiocephaloides longicollis, Caligus ligusticus and Gnathia vorax. We also report the first records of two parasite species in the wild sharpsnout seabream, the polyopisthocotylean monogeneans Atrispinum seminalis and Sparicotyle chrysophrii. Previously, these parasites had only been recorded in farmed sharpsnout seabream. Most parasites in the skin, gills and alimentary tract disappeared under the conditions of captivity, with the exception of the monogeneans of the genus Lamellodiscus. The information provided about the sharpsnout seabream parasite fauna will be useful to prevent possible problems in fish farms due to some parasite species. Many parasites of the sharpsnout seabream recorded in the present study are shared by the main fish species in Mediterranean aquaculture, the gilthead seabream, thus suggesting the possibility of cross-infections.

  3. The importance of the age when evaluating mercury pollution in fishes: the case of Diplodus sargus (Pisces, Sparidae in the NW Mediterranean

    Directory of Open Access Journals (Sweden)

    Margarida Casadevall

    2017-01-01

    Full Text Available The aim of this study was to analyse the concentration of mercury (Hg in the muscle of a common littoral, omnivorous fish such as the white seabream, Diplodus sargus, and to evaluate its relationship with the age and size of the specimens. Large, older predatory fishes have typically been the main target species for risk assessment of Hg intake in humans. The white seabream is neither a big fish nor a predator, but all sizes of NW Mediterranean specimens of this species showed high levels of Hg, with clear increases in older specimens. In addition, although the Se:Hg molar ratio was high and could reduce the impact of high concentrations of Hg in smaller fishes, it could not in the older specimens of D. sargus analysed because it decreased with age. This is not a major concern for human health because the white seabream is not a widely consumed species. However, in special situations involving toddlers, children and women of childbearing age, problems might arise if the white seabream or similar species are consumed in place of those that current recommendations advise against eating. In these cases it is very important to consider the species of fish consumed in each country and carefully assess the risk of Hg intake.

  4. Somatic indexes, chemical-nutritive characteristics and metal content in caught and reared sharpsnout seabream (Diplodus puntazzo

    Directory of Open Access Journals (Sweden)

    Giuseppe Moniello

    2010-01-01

    Full Text Available The aim of this study was to compare some somatic indexes, chemical-nutritive characteristics and the contents of some metals (Pb, Cu, Cr and Zn in the whole body and fillet from caught and reared sharpsnout seabream (Diplodus puntazzo. The fish came from three different conditions: reared in marine cages (R, captured in a natural lagoon (L and in the Mediterranean sea (S. Thirty fish per group, divided into three weight categories (100±15.3, 200±18.7 and 300±20.4g, were used for the trial. Reared sharpsnout seabream showed higher amounts of celomatic fat (3.41%, 2.43%, 0.21%, respectively for R, L and S and total lipid (13.86%, 11.23% and 5.06% respectively for R, L and S, and lower moisture (64.14%, 65.54%, 71.53% and protein (17.73, 19.03 and 19.17% than those caught in the lagoon and sea. The whole body of reared fish contained lower amounts of lead (0.70, 0.75 and 0.97mg/kg, respectively for R, L and S, copper (0.15, 0.38, 0.25mg/kg chrome (2.19, 3.52, 3.77mg/kg and higher zinc contents (63.47, 53.42, 47.31mg/kg than caught fish. Fatty acids from sharpsnout seabream fillets showed a high lipid quality as confirmed also by low values of Thrombogenic index (0.36, 0.30 and 0.22, respectively for L, S, R and Atherogenic index (0.47, 0.42 and 0.33, respectively for L, S, R. Reared sharpsnout seabream showed lower saturated fatty acid values (26.44%, 32.21%, 34.85%, respectively for R, S, L and higher oleic acid amount (21.61%, 19.15%, 11.99%, respectively for R, L and S. The subjects captured in the sea had a higher arachidonic acid content (5.44%, 1.76%, 0.59%, respectively for S, L, R. In the weight categories, the 100g subjects, showed higher incidence of viscera (VSI: 4.32%, 3.12% and 2.92%, respectively for 100, 200 and 300g and liver (HIS: 2.20%, 1.97%, and 1.77%, respectively for 100, 200 and 300g, higher moisture (69.49%, 67.03%, 64.69% and lower lipid rate (7.64%, 10.18%, 12.32%.

  5. Inorganic mercury accumulation in brain following waterborne exposure elicits a deficit on the number of brain cells and impairs swimming behavior in fish (white seabream-Diplodus sargus).

    Science.gov (United States)

    Pereira, Patrícia; Puga, Sónia; Cardoso, Vera; Pinto-Ribeiro, Filipa; Raimundo, Joana; Barata, Marisa; Pousão-Ferreira, Pedro; Pacheco, Mário; Almeida, Armando

    2016-01-01

    The current study contributes to fill the knowledge gap on the neurotoxicity of inorganic mercury (iHg) in fish through the implementation of a combined evaluation of brain morphometric alterations (volume and total number of neurons plus glial cells in specific regions of the brain) and swimming behavior (endpoints related with the motor activity and mood/anxiety-like status). White seabream (Diplodus sargus) was exposed to realistic levels of iHg in water (2μgL(-1)) during 7 (E7) and 14 days (E14). After that, fish were allowed to recover for 28 days (PE28) in order to evaluate brain regeneration and reversibility of behavioral syndromes. A significant reduction in the number of cells in hypothalamus, optic tectum and cerebellum was found at E7, accompanied by relevant changes on swimming behavior. Moreover, the decrease in the number of neurons and glia in the molecular layer of the cerebellum was followed by a contraction of its volume. This is the first time that a deficit on the number of cells is reported in fish brain after iHg exposure. Interestingly, a recovery of hypothalamus and cerebellum occurred at E14, as evidenced by the identical number of cells found in exposed and control fish, and volume of cerebellum, which might be associated with an adaptive phenomenon. After 28 days post-exposure, the optic tectum continued to show a decrease in the number of cells, pointing out a higher vulnerability of this region. These morphometric alterations coincided with numerous changes on swimming behavior, related both with fish motor function and mood/anxiety-like status. Overall, current data pointed out the iHg potential to induce brain morphometric alterations, emphasizing a long-lasting neurobehavioral hazard. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Effects of the partial substitution of fish meal by soy bean meal with or without mannanoligosaccharide and fructooligosaccharide on the growth and feed utilization of sharpsnout seabream, Diplodus puntazzo (Cetti, 1777: preliminary results

    Directory of Open Access Journals (Sweden)

    Antonino Nizza

    2011-07-01

    Full Text Available The present study was carried out in order to investigate the effects of the mannanoligosaccharide (MOS and fructooligosaccharide (FOS on sharpsnout seabream, Diplodus puntazzo in the context of partial fish meal substitution by soybean meal. One-hundred-forty-four sharpsnout seabream of about 100 g initial body weight were randomly divided in 12 experimental tanks (180 litre each. Testing conditions included 12 fish per tank, with triplicate tanks for treatment. The experimental period lasted 114 days. Average water temperature was 21.9±1.6°C, salinity was 30.0‰ and pH ranged from 7 to 8. Four isonitrogenous-isolipidic diets were tested: a control diet (FM with fish meal as the sole protein source; a second diet (SBM with approximately 40% of the protein supplied by soybean meal. The remaining two diets were formulated adding 8 g of MOS and FOS per kg of the SBM diet respectively. Average final weight, specific growth rate, feed conversion ratio and protein efficiency ratio remained unaffected by partial fish meal substitution and by MOS or FOS supplementation. Also apparent digestibility coefficients values for organic matter, protein, lipid and energy were not significantly affected by dietary treatment.

  7. Biotransformation modulation and genotoxicity in white seabream upon exposure to paralytic shellfish toxins produced by Gymnodinium catenatum

    International Nuclear Information System (INIS)

    Reis Costa, Pedro; Pereira, Patrícia; Guilherme, Sofia; Barata, Marisa; Nicolau, Lídia; Santos, Maria Ana; Pacheco, Mário; Pousão-Ferreira, Pedro

    2012-01-01

    Fish are recurrently exposed to paralytic shellfish toxins (PSTs) produced by Gymnodinium catenatum. Nevertheless, the knowledge regarding metabolism of PSTs and their toxic effects in fish is scarce. Consequently, the current study aims to investigate the role of phase I and II detoxification enzymes on PST metabolism in the liver of white seabream (Diplodus sargus), assessing ethoxyresorufin-O-deethylase (EROD) and glutathione S-transferase (GST) activities. Moreover, the genotoxic potential of PSTs was examined through the erythrocytic nuclear abnormality (ENA) assay. Fish were intracoelomically (IC) injected with a nominal dose (expressed as saxitoxin equivalents) of 1.60 μg STXeq kg −1 semipurified from a G. catenatum cell culture with previously determined toxin profile. Fish were sacrificed 2 and 6 days after IC injection. PST levels determined in fish liver were15.2 and 12.2 μg STXeq kg −1 , respectively, at 2 and 6 days after the injection. Though several PSTs were administered, only dcSTX was detected in the liver after 2 and 6 days. This was regarded as an evidence that most of the N-sulfocarbamoyl and decarbamoyl toxins were rapidly biotransformed in D. sargus liver and/or eliminated. This was corroborated by a hepatic GST activity induction at 2 days after injection. Hepatic EROD activity was unresponsive to PSTs, suggesting that these toxins enter phase II of biotransformation directly. The genotoxic potential of PSTs was also demonstrated; these toxins were able to induce cytogenetic damage, such as chromosome (or chromatid) breaks or loss and segregational anomalies, measured by the ENA assay. Overall, this study pointed out the ecological risk associated with the contamination of fish with PSTs generated by G. catenatum blooms, providing the necessary first data for a proper interpretation of biomonitoring programs aiming to assess the impact of phytoplankton blooms in fish.

  8. Biotransformation modulation and genotoxicity in white seabream upon exposure to paralytic shellfish toxins produced by Gymnodinium catenatum

    Energy Technology Data Exchange (ETDEWEB)

    Reis Costa, Pedro, E-mail: prcosta@ipimar.pt [IPIMAR - National Institute for Biological Resources (INRB/IPIMAR), Av. Brasilia, 1449-006 Lisboa (Portugal); Pereira, Patricia [IPIMAR - National Institute for Biological Resources (INRB/IPIMAR), Av. Brasilia, 1449-006 Lisboa (Portugal); Department of Biology and CESAM, Aveiro University, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Guilherme, Sofia [Department of Biology and CESAM, Aveiro University, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Barata, Marisa; Nicolau, Lidia [IPIMAR - National Institute for Biological Resources (INRB/IPIMAR), Av. 5 Outubro, 8700-305 Olhao (Portugal); Santos, Maria Ana; Pacheco, Mario [Department of Biology and CESAM, Aveiro University, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Pousao-Ferreira, Pedro [IPIMAR - National Institute for Biological Resources (INRB/IPIMAR), Av. 5 Outubro, 8700-305 Olhao (Portugal)

    2012-01-15

    Fish are recurrently exposed to paralytic shellfish toxins (PSTs) produced by Gymnodinium catenatum. Nevertheless, the knowledge regarding metabolism of PSTs and their toxic effects in fish is scarce. Consequently, the current study aims to investigate the role of phase I and II detoxification enzymes on PST metabolism in the liver of white seabream (Diplodus sargus), assessing ethoxyresorufin-O-deethylase (EROD) and glutathione S-transferase (GST) activities. Moreover, the genotoxic potential of PSTs was examined through the erythrocytic nuclear abnormality (ENA) assay. Fish were intracoelomically (IC) injected with a nominal dose (expressed as saxitoxin equivalents) of 1.60 {mu}g STXeq kg{sup -1} semipurified from a G. catenatum cell culture with previously determined toxin profile. Fish were sacrificed 2 and 6 days after IC injection. PST levels determined in fish liver were15.2 and 12.2 {mu}g STXeq kg{sup -1}, respectively, at 2 and 6 days after the injection. Though several PSTs were administered, only dcSTX was detected in the liver after 2 and 6 days. This was regarded as an evidence that most of the N-sulfocarbamoyl and decarbamoyl toxins were rapidly biotransformed in D. sargus liver and/or eliminated. This was corroborated by a hepatic GST activity induction at 2 days after injection. Hepatic EROD activity was unresponsive to PSTs, suggesting that these toxins enter phase II of biotransformation directly. The genotoxic potential of PSTs was also demonstrated; these toxins were able to induce cytogenetic damage, such as chromosome (or chromatid) breaks or loss and segregational anomalies, measured by the ENA assay. Overall, this study pointed out the ecological risk associated with the contamination of fish with PSTs generated by G. catenatum blooms, providing the necessary first data for a proper interpretation of biomonitoring programs aiming to assess the impact of phytoplankton blooms in fish.

  9. Biotransformation modulation and genotoxicity in white seabream upon exposure to paralytic shellfish toxins produced by Gymnodinium catenatum.

    Science.gov (United States)

    Costa, Pedro Reis; Pereira, Patrícia; Guilherme, Sofia; Barata, Marisa; Nicolau, Lídia; Santos, Maria Ana; Pacheco, Mário; Pousão-Ferreira, Pedro

    2012-01-15

    Fish are recurrently exposed to paralytic shellfish toxins (PSTs) produced by Gymnodinium catenatum. Nevertheless, the knowledge regarding metabolism of PSTs and their toxic effects in fish is scarce. Consequently, the current study aims to investigate the role of phase I and II detoxification enzymes on PST metabolism in the liver of white seabream (Diplodus sargus), assessing ethoxyresorufin-O-deethylase (EROD) and glutathione S-transferase (GST) activities. Moreover, the genotoxic potential of PSTs was examined through the erythrocytic nuclear abnormality (ENA) assay. Fish were intracoelomically (IC) injected with a nominal dose (expressed as saxitoxin equivalents) of 1.60 μg STXeq kg⁻¹ semipurified from a G. catenatum cell culture with previously determined toxin profile. Fish were sacrificed 2 and 6 days after IC injection. PST levels determined in fish liver were 15.2 and 12.2 μg STXeq kg⁻¹, respectively, at 2 and 6 days after the injection. Though several PSTs were administered, only dcSTX was detected in the liver after 2 and 6 days. This was regarded as an evidence that most of the N-sulfocarbamoyl and decarbamoyl toxins were rapidly biotransformed in D. sargus liver and/or eliminated. This was corroborated by a hepatic GST activity induction at 2 days after injection. Hepatic EROD activity was unresponsive to PSTs, suggesting that these toxins enter phase II of biotransformation directly. The genotoxic potential of PSTs was also demonstrated; these toxins were able to induce cytogenetic damage, such as chromosome (or chromatid) breaks or loss and segregational anomalies, measured by the ENA assay. Overall, this study pointed out the ecological risk associated with the contamination of fish with PSTs generated by G. catenatum blooms, providing the necessary first data for a proper interpretation of biomonitoring programs aiming to assess the impact of phytoplankton blooms in fish. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Host–parasite relationship of Ceratomyxa puntazzi n. sp. (Myxozoa: Myxosporea) and sharpsnout seabream Diplodus puntazzo (Walbaum, 1792) from the Mediterranean with first data on ceratomyxid host specificity in sparids

    Czech Academy of Sciences Publication Activity Database

    Alama-Bermejo, G.; Raga, J. A.; Holzer, Astrid S.

    2011-01-01

    Roč. 182, 2/4 (2011), s. 181-192 ISSN 0304-4017 Institutional research plan: CEZ:AV0Z60220518 Keywords : Myxozoa * Ceratomyxa puntazzi * Diplodus puntazzo * Sparus aurata and Diplodus annularis * Histopathology * SSU rDNA phylogeny * Transmission electron microscopy Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.579, year: 2011

  11. Risk assessment for parasites in cultures of Diplodus puntazzo (Sparidae) in the Western Mediterranean: prospects of cross infection with Sparus aurata.

    Science.gov (United States)

    Sánchez-García, Neus; Raga, Juan Antonio; Montero, Francisco E

    2014-08-29

    The sharpsnout seabream Diplodus puntazzo is of interest in Mediterranean fish farming. Disease is an important problem because parasites can spread quickly in culture conditions and fish often develop high parasite burdens. Here we assess the risk that documented parasites pose to the sustainability of D. puntazzo farming. This study specifically considers metazoan and protist parasites recorded from wild and farmed D. puntazzo in scientific literature. Risk assessment studies involve the identification, characterization and qualitative quantification of the risk in question (parasitoses in this case) and the probability of establishment. We considered the parasite species which may be difficult to manage as a priority for research into potential management strategies. Those parasites which could be transmitted from cultures of gilthead seabream (Sparus aurata) were also included in this study. Four groups of parasites represented a risk to D. puntazzo farming, ranging from moderate to high: Ciliophora, Myxozoa, Monogenea and Copepoda. Three parasite species were considered high risk to D. puntazzo cultures: Amyloodinium sp., Cryptocaryon sp. and Enteromyxum leei. These species were responsible for high mortalities in cultures of these and other fish species. In addition Sparicotyle chrysophrii, Caligus ligusticus and Gnathia vorax entail a moderate risk to D. puntazzo Mediterranean farms. No important episodes have been related to caligids and isopods in Mediterranean sparids, nevertheless they should be properly managed to prevent future problems. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Ontogenetic dietary shift and morphological correlates for Diplodus ...

    African Journals Online (AJOL)

    Allometric growth patterns of functional morphological variables that reflect resource use in fish were correlated with the diet of Diplodus capensis in southern Angola. A total of 114 individuals (76–336 mm FL) were collected for stomach content analysis and a further 35 individuals (80–320 mm FL) for morphometric ...

  13. Comparison of the population structure and life-history parameters ...

    African Journals Online (AJOL)

    Blacktail seabream Diplodus capensis were sampled from proximate (10 km apart) exploited and unexploited areas in southern Angola to compare their population structures and life-history parameters. Females dominated the larger size and older age classes in the unexploited area. In the exploited area the length and ...

  14. Arachidonic acid reduces the stress response of gilthead seabream Sparus aurata L.

    NARCIS (Netherlands)

    Anholt, R.D. van; Spanings, F.A.T.; Koven, WM; Nixon, O.; Wendelaar Bonga, S.E.

    2004-01-01

    In this study the influence of the dietary level of the fatty acid arachidonic acid (ArA, 20:4n-6) was determined on the acute stress response and osmoregulation of adult gilthead seabream Sparus aurata L. Seabream were fed a diet containing either 0.9% or 2.4% of total fatty acids as ArA for 18

  15. Unveiling the neurotoxicity of methylmercury in fish (Diplodus sargus) through a regional morphometric analysis of brain and swimming behavior assessment.

    Science.gov (United States)

    Puga, Sónia; Pereira, Patrícia; Pinto-Ribeiro, Filipa; O'Driscoll, Nelson J; Mann, Erin; Barata, Marisa; Pousão-Ferreira, Pedro; Canário, João; Almeida, Armando; Pacheco, Mário

    2016-11-01

    The current study aims to shed light on the neurotoxicity of MeHg in fish (white seabream - Diplodus sargus) by the combined assessment of: (i) MeHg toxicokinetics in the brain, (ii) brain morphometry (volume and number of neurons plus glial cells in specific brain regions) and (iii) fish swimming behavior (endpoints associated with the motor performance and the fear/anxiety-like status). Fish were surveyed for all the components after 7 (E7) and 14 (E14) days of dietary exposure to MeHg (8.7μgg -1 ), as well as after a post-exposure period of 28days (PE28). MeHg was accumulated in the brain of D. sargus after a short time (E7) and reached a maximum at the end of the exposure period (E14), suggesting an efficient transport of this toxicant into fish brain. Divalent inorganic Hg was also detected in fish brain along the experiment (indicating demethylation reactions), although levels were 100-200 times lower than MeHg, which pinpoints the organic counterpart as the great liable for the recorded effects. In this regard, a decreased number of cells in medial pallium and optic tectum, as well as an increased hypothalamic volume, occurred at E7. Such morphometric alterations were followed by an impairment of fish motor condition as evidenced by a decrease in the total swimming time, while the fear/anxiety-like status was not altered. Moreover, at E14 fish swam a greater distance, although no morphometric alterations were found in any of the brain areas, probably due to compensatory mechanisms. Additionally, although MeHg decreased almost two-fold in the brain during post-exposure, the levels were still high and led to a loss of cells in the optic tectum at PE28. This is an interesting result that highlights the optic tectum as particularly vulnerable to MeHg exposure in fish. Despite the morphometric alterations reported in the optic tectum at PE28, no significant changes were found in fish behavior. Globally, the effects of MeHg followed a multiphasic profile, where

  16. Immunotoxicological effects of inorganic arsenic on gilthead seabream (Sparus aurata L.)

    Energy Technology Data Exchange (ETDEWEB)

    Guardiola, F.A.; Gónzalez-Párraga, M.P.; Cuesta, A. [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Meseguer, J. [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Martínez, S.; Martínez-Sánchez, M.J.; Pérez-Sirvent, C. [Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Esteban, M.A., E-mail: aesteban@um.es [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain)

    2013-06-15

    Highlights: •Short exposure to arsenic increases the hepato-somatic index and produces histopathological alterations in the liver. •Arsenic is bioaccumulated in the liver of gilthead seabream but no in the muscle. •Arsenic-exposure affects the innate immune system in the gilthead seabream. •Ten days of exposure to As enhances the immune parameters. -- Abstract: Arsenic (As) has been associated with multitude of animal and human health problems; however, its impact on host immune system has not been extensively investigated. In fish, there are very few works on the potential risks or problems associated to the presence of arsenic. In the present study we have evaluated the effects of exposure (30 days) to sub-lethal concentrations of arsenic (5 μM As{sub 2}O{sub 3}) in the teleost fish gilthead seabream (Sparus aurata), with special emphasis in the innate immune response. The arsenic concentration was determined using atomic fluorescence spectrometry (AFS) in liver and muscle of exposed fish showing As accumulation in the liver after 30 days of exposure. The hepatosomatic index was increased at significant extent after 10 days but returned to control values after 30 days of exposure. Histological alterations in the liver were observed including hypertrophy, vacuolization and cell-death processes. Focusing on the immunological response, the humoral immune parameters (seric IgM, complement and peroxidase activities) were no affected to a statistically significant extent. Regarding the cellular innate parameters, head-kidney leucocyte peroxidase, respiratory burst and phagocytic activities were significantly increased after 10 days of exposition compared to the control fish. Overall, As-exposure in the seabream affects the immune system. How this might interfere with fish biology, aquaculture management or human consumers warrants further investigations. This paper describes, for the first time, the immunotoxicological effects of arsenic exposure in the

  17. RANCIDITY DEVELOPMENT DURING FROZEN STORAGE OF FILLETS FROM GILTHEAD SEABREAM (Sparus aurata REARED IN ITALY

    Directory of Open Access Journals (Sweden)

    P.P. Gatta

    2013-02-01

    Full Text Available Lipid oxidation indices (Free Fatty Acids-FFA, Peroxide Value-PV and Thiobarbituric Acid-TBA were evaluated in frozen fillets from seabream reared in Italy in: land based facilities (recirculation systems, lagoons or net-cages. Statistically significant differences emerged among seabream sources for all indices. Quality loss related to rancidity seemed to have been affected by both storage time and culturing system.

  18. Mating behaviour and gamete release in gilthead seabream (Sparus aurata, Linnaeus 1758) held in captivity

    Energy Technology Data Exchange (ETDEWEB)

    Ibarra-Zatarain, Z.; Duncan, N.

    2015-07-01

    The present study aimed to describe the reproductive behaviour of gilthead seabream (Sparus aurata) in captivity. Twenty-four mature gilthead seabream, divided in two tanks, were utilized for the present study. Reproductive behaviour was recorded using submersibles cameras. A total of 67 spawning events were analysed. The mean duration time that gilthead seabream spent spawning was 54 ± 4 min/day, during which mean number of individual spawning events was 5.6 ± 0.2. The mean volume of eggs produced by both broodstocks was 405 ± 13.4 mL with a fertilization rate of 91.6 ± 0.4%. The reproductive behaviour began with a schooling behaviour and then forming light aggregations. From an aggregation or an encounter while swimming freely a female initiated a spawning rush followed by one or more males to gametes liberation. The spawning rush was brief, 1.6 ± 0.5 sec, over an approximately 1.7 ± 0.2 m distance from the tank bottom to the water surface. Pair spawning, between a single female and male, was the most common (71.6%). Group spawning was less common and involved a single female spawning with two males (22.5%) or three males (4.9%). Spawning rushes involving more than one female were not observed. Gilthead seabream in the present study presented a tendency to pair spawn and eggs collected as a “spawn” were actually the sum of many separate spawning events over a short time period. This is the first description of gilthead seabream spawning and the findings help to understand microsatellite based observations of spawning kinetics. (Author)

  19. LAJU RESPIRASI INDUK IKAN BLACKHEAD SEABREAM Acanthopagrus schlegelii PADA SUHU PEMELIHARAAN YANG BERBEDA

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    Vitas Atmadi Prakoso

    2017-10-01

    Full Text Available Laju respirasi hewan akuatik memiliki hubungan yang erat dengan metabolisme. Tingkat metabolisme hewan merupakan variabel yang dapat dipengaruhi faktor dalam maupun luar, salah satunya adalah suhu. Pada ikan, proses metabolisme juga berkorelasi dengan suhu. Salah satu jenis ikan yang perlu dikaji laju respirasinya adalah ikan blackhead seabream Acanthopagrus schlegelii yang merupakan spesies ikan laut yang popular di Korea Selatan, sehingga diperlukan lebih banyak informasi lagi mengenai laju respirasi ikan ini untuk mengoptimalkan metabolisme ikan ini dan berdampak kepada produktivitas budidaya. Penelitian ini bertujuan untuk mengevaluasi laju respirasi induk ikan blackhead seabream pada beberapa tingkatan suhu. Ikan blackhead seabream (panjang total 29,3 ± 2,2 cm dan bobot tubuh 538,3 ± 43,0 g diteliti menggunakan respirometer dalam sistem resirkulasi. Tiga kelompok percobaan dilakukan untuk mengukur laju respirasi berdasarkan perubahan suhu pemeliharaan (15°C, 20°C, dan 25°C. Hasil penelitian menunjukkan bahwa kecenderungan laju respirasi meningkat secara linier dengan peningkatan suhu perlakuan, dengan nilai tertinggi sebesar 164,8 ± 30,7 mg O2/kg/jam pada 25°C dan nilai terendah sebesar 72,4 ± 8,1 mg O2/kg/jam pada 15°C. Sementara itu, frekuensi pernapasan berkorelasi positif terhadap kenaikan suhu. Berdasarkan penelitian ini, dapat disimpulkan bahwa perubahan suhu dari 15°C ke 25°C menyebabkan peningkatan laju respirasi pada induk ikan blackhead seabream. It is well known that a close relationship exists between respiration rate and metabolism in aquatic animal. In fish, the metabolic rate is influenced by internal or external factors, such as temperature. This research observed the respiration rate of blackhead seabream, Acanthopagrus schlegelii, which is one of the popular marine fish species in South Korea. Despite the fish popularity, very few information are available about the fish’s respiration rate which is important

  20. Two alternatively spliced GPR39 transcripts in seabream: molecular cloning, genomic organization, and regulation of gene expression by metabolic signals.

    Science.gov (United States)

    Zhang, Yong; Liu, Yun; Huang, Xigui; Liu, Xiaochun; Jiao, Baowei; Meng, Zining; Zhu, Pei; Li, Shuisheng; Lin, Haoran; Cheng, Christopher H K

    2008-12-01

    Two GPR39 transcripts, designated as sbGPR39-1a and sbGPR39-1b, were identified in black seabream (Acanthopagrus schlegeli). The deduced amino acid (aa) sequence of sbGPR39-1a contains 423 residues with seven putative transmembrane (TM) domains. On the other hand, sbGPR39-1b contains 284 aa residues with only five putative TM domains. Northern blot analysis confirmed the presence of two GPR39 transcripts in the seabream intestine, stomach, and liver. Apart from seabream, the presence of two GPR39 transcripts was also found to exist in a number of teleosts (zebrafish and pufferfish) and mammals (human and mouse). Analysis of the GPR39 gene structure in different species suggests that the two GPR39 transcripts are generated by alternative splicing. When the seabream receptors were expressed in cultured HEK293 cells, Zn(2)(+) could trigger sbGPR39-1a signaling through the serum response element pathway, but no such functionality could be detected for the sbGPR39-1b receptor. The two receptors were found to be differentially expressed in seabream tissues. sbGPR39-1a is predominantly expressed in the gastrointestinal tract. On the other hand, sbGPR39-1b is widely expressed in most central and peripheral tissues except muscle and ovary. The expression of sbGPR39-1a in the intestine and the expression of sbGPR39-1b in the hypothalamus were decreased significantly during food deprivation in seabream. On the contrary, the expression of the GH secretagogue receptors (sbGHSR-1a and sbGHSR-1b) was significantly increased in the hypothalamus of the food-deprived seabream. The reciprocal regulatory patterns of expression of these two genes suggest that both of them are involved in controlling the physiological response of the organism during starvation.

  1. Metabolic fingerprinting of gilthead seabream (Sparus aurata liver to track interactions between dietary factors and seasonal temperature variations

    Directory of Open Access Journals (Sweden)

    Tomé S. Silva

    2014-08-01

    Full Text Available Farmed gilthead seabream is sometimes affected by a metabolic syndrome, known as the “winter disease”, which has a significant economic impact in the Mediterranean region. It is caused, among other factors, by the thermal variations that occur during colder months and there are signs that an improved nutritional status can mitigate the effects of this thermal stress. For this reason, a trial was undertaken where we assessed the effect of two different diets on gilthead seabream physiology and nutritional state, through metabolic fingerprinting of hepatic tissue. For this trial, four groups of 25 adult gilthead seabream were reared for 8 months, being fed either with a control diet (CTRL, low-cost commercial formulation or with a diet called “Winter Feed” (WF, high-cost improved formulation. Fish were sampled at two time-points (at the end of winter and at the end of spring, with liver tissue being taken for FT-IR spectroscopy. Results have shown that seasonal temperature variations constitute a metabolic challenge for gilthead seabream, with hepatic carbohydrate stores being consumed over the course of the inter-sampling period. Regarding the WF diet, results point towards a positive effect in terms of performance and improved nutritional status. This diet seems to have a mitigating effect on the deleterious impact of thermal shifts, confirming the hypothesis that nutritional factors can affect the capacity of gilthead seabream to cope with seasonal thermal variations and possibly contribute to prevent the onset of “winter disease”.

  2. Seasonal Variation in Trawl Codend Selectivity for Annular Sea Bream (Diplodus annularis L., 1758)

    OpenAIRE

    ÖZBİLGİN, Hüseyin; TOSUNOĞLU, Zafer; TOKAÇ, Adnan; METİN, Gülnur

    2014-01-01

    This study investigated the selectivity of a 40 mm mesh size polyethylene codend commonly used by Turkish demersal trawlers. Seasonal selectivity data were collected for annular sea bream (Diplodus annularis), which is the most abundant discard species in the catch composition in Gülbahçe Bay. Four sets of data were collected in spring (4-18 April 2002), summer (10-25 July 2002), autumn (26 September-2 October 2002) and winter (22-23 January 2003). The selectivity of the same codend was teste...

  3. Examination of the Fish Price Offered for Sale During 2012-2013 Fishing Season in Sinop, Turkey

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    Şennan Yücel

    2017-10-01

    Full Text Available The aim of the study was to determine the monthly price distribution of the offered fish species for sale within the scope of information received from the centers engaged in the sale of retail fish during 2012-2013 fishing season in Sinop, Turkey. The enterprises were grouped as I (the most, II (middle and III (the least according to the sales volume and fish species. Each group was represented by two different fish enterprise and so a total of six separate enterprises were determined by purpose sampling method. During the study, sale prices and fish species were obtained twice every month at the same time of day. It was determined that anchovy (Engraulis encrasicolus ponticus, horse mackerel (Trachurus trachurus, bluefish (Pomatomus saltatrix, atlantic bonito (Sarda sarda, twait shad (Alosa fallax nilotica, needlefish (Belone belone, mullet (Mugil cephalus, shi drum (Umbrina cirrosa, brown meagre (Sciana umbra, common two-banded seabream (Diplodus vulgaris, annular bream (Diplodus annularis, tub gurnard (Trigla lucerna, picarel (Maena smaris, turbot (Psetta maxima, red mullet (Mullus barbatus, whiting (Merlangus merlangus, scorpion fish (Scorpaena porcus, goby (Gobius niger were offered for sale in fish markets. While the prices of higher economic valued fish species like anchovy, bluefish, atlantic bonito and turbot prices were different between the enterprises, the prices of horse mackerel, red mullet and whiting species were not different. When considering the fish prices based on years, the prices of horse mackerel, bluefish, atlantic bonito, red mullet and haddock during 2012-2013 years were close to the average price of 2008-2012 years and the prices of anchovy and turbot during 2012-2013 years were higher than the average price of 2008-2012 years in Sinop.

  4. The Effect of Phenanthrene on Some Hematological Indices Yellowfin Seabream (Acanthopagrus Latus

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    Mehrnaz Shirmohammadi

    2018-01-01

    Full Text Available Background: We examined the effects of phenanthrene (Phe on hematological parameters of yellowfin seabream (Acanthopagrus latus. Methods: The research was carried out in Jan 2016 at Khorramshahr University of Marine Science and Technology, Khorramshahr, Iran. Fish were injected with different concentrations (0, 2, 20 and 40 mg/kg of Phe and blood, samples were taken from fish 1, 4, 7 and 14 d after injection. Results: Results of Phe-treated fish showed a decrease in red blood cell and white blood cell counts, hematocrit amount after 4 d and in hemoglobin concentration after 7 d (P<0.05. Mean corpuscular hemoglobin concentration was enhanced in fish exposed to Phe up to day 4 (P<0.05. Phe-exposed fish showed an increase in the percentage of neutrophils with a decrease in the percentage of lymphocytes (P<0.05 and did not represent any effects on percentage of monocytes and eosinophils, mean corpuscular volume and mean corpuscular hemoglobin concentration. Conclusion: Changes in hematological parameters after exposure to Phe result in a decrease of non-specific immunity.

  5. Biochemical biomarker responses to pollution in selected sentinel organisms across the Eastern Mediterranean and the Black Sea

    KAUST Repository

    Tsangaris, Catherine; Moschino, Vanessa; Strogyloudi, Evangelia; Coatu, Valentina; Ramšak, Andreja; Abu Alhaija, Rana; Carvalho, Susana; Felline, Serena; Kosyan, Alisa; Lazarou, Yiota; Hatzianestis, Ioannis; Oros, Andra; Tiganus, Daniela

    2015-01-01

    Pollution effects were assessed by means of biochemical biomarkers (catalase, glutathione S-transferase and acetylcholinesterase activities, and metallothioneins content) in five species at selected coastal sites across the Eastern Mediterranean and the Black Sea. The mussel Mytilus galloprovincialis, a well-established sentinel species, was investigated in the Adriatic Sea, Aegean Sea, and Black Sea. The mussel Brachidontes pharaonis and the striped red mullet Mullus surmuletus were used in the Levantine Sea where M. galloprovincialis is not present. The white seabream Diplodus sargus sargus and the gastropod Rapana venosa were additionally sampled in the Adriatic and the Black Sea, respectively. Mussels showed catalase, glutathione S-transferase, and acetylcholinesterase responses to pollution in most geographical areas while the response of metallothioneins was restricted to a few sites. R. venosa showed marked responses of catalase and metallothioneins whereas both fish species did not generally exhibit variations in biomarker values among sites. The approach based on the reference deviation concept using the “Integrated Biological Responses version 2” index was useful for the interpretation of overall biomarker responses.

  6. Biochemical biomarker responses to pollution in selected sentinel organisms across the Eastern Mediterranean and the Black Sea

    KAUST Repository

    Tsangaris, Catherine

    2015-09-23

    Pollution effects were assessed by means of biochemical biomarkers (catalase, glutathione S-transferase and acetylcholinesterase activities, and metallothioneins content) in five species at selected coastal sites across the Eastern Mediterranean and the Black Sea. The mussel Mytilus galloprovincialis, a well-established sentinel species, was investigated in the Adriatic Sea, Aegean Sea, and Black Sea. The mussel Brachidontes pharaonis and the striped red mullet Mullus surmuletus were used in the Levantine Sea where M. galloprovincialis is not present. The white seabream Diplodus sargus sargus and the gastropod Rapana venosa were additionally sampled in the Adriatic and the Black Sea, respectively. Mussels showed catalase, glutathione S-transferase, and acetylcholinesterase responses to pollution in most geographical areas while the response of metallothioneins was restricted to a few sites. R. venosa showed marked responses of catalase and metallothioneins whereas both fish species did not generally exhibit variations in biomarker values among sites. The approach based on the reference deviation concept using the “Integrated Biological Responses version 2” index was useful for the interpretation of overall biomarker responses.

  7. Biochemical biomarker responses to pollution in selected sentinel organisms across the Eastern Mediterranean and the Black Sea.

    Science.gov (United States)

    Tsangaris, Catherine; Moschino, Vanessa; Strogyloudi, Evangelia; Coatu, Valentina; Ramšak, Andreja; Alhaija, Rana Abu; Carvalho, Susana; Felline, Serena; Kosyan, Alisa; Lazarou, Yiota; Hatzianestis, Ioannis; Oros, Andra; Tiganus, Daniela

    2016-01-01

    Pollution effects were assessed by means of biochemical biomarkers (catalase, glutathione S-transferase and acetylcholinesterase activities, and metallothioneins content) in five species at selected coastal sites across the Eastern Mediterranean and the Black Sea. The mussel Mytilus galloprovincialis, a well-established sentinel species, was investigated in the Adriatic Sea, Aegean Sea, and Black Sea. The mussel Brachidontes pharaonis and the striped red mullet Mullus surmuletus were used in the Levantine Sea where M. galloprovincialis is not present. The white seabream Diplodus sargus sargus and the gastropod Rapana venosa were additionally sampled in the Adriatic and the Black Sea, respectively. Mussels showed catalase, glutathione S-transferase, and acetylcholinesterase responses to pollution in most geographical areas while the response of metallothioneins was restricted to a few sites. R. venosa showed marked responses of catalase and metallothioneins whereas both fish species did not generally exhibit variations in biomarker values among sites. The approach based on the reference deviation concept using the "Integrated Biological Responses version 2" index was useful for the interpretation of overall biomarker responses.

  8. Age-dependent QTL affecting body weight in gilthead seabream (Sparus aurata L.

    Directory of Open Access Journals (Sweden)

    D. LOUKOVITIS

    2016-09-01

    Full Text Available We examined 24 maternal half-sib families of gilthead seabream to identify quantitative trait loci (QTL associated with body weight at four time points during a production cycle. 57 brooders and 637 offspring were genotyped for 14 informative microsatellite markers, spanning linkage groups 1 and 21. The QTL detection method was based on half-sib interval mapping analysis through a linear regression approach. One QTL was found significant at all time points in linkage group 1, with its effect having different profile across time, and one QTL in linkage group 21 that seems to impact body weight at a later growth stage of the species. Current results verified previously published QTL for growth in the above linkage groups, using a different genetic background of seabream. These QTL can be considered as valuable candidates for use in marker-assisted selective breeding programs, aiming at high rates of genetic improvement for growth in S. aurata.

  9. Parasites as biological tags for stock identification of blackspot seabream, Pagellus bogaraveo, in Portuguese northeast Atlantic waters

    Directory of Open Access Journals (Sweden)

    Margarida Hermida

    2013-10-01

    Full Text Available In this study the following parasites were selected as biological tags for the identification of blackspot seabream (Pagellus bogaraveo stocks in the northeast Atlantic: Diphterostomum vividum (Digenea: Zoogonidae, Anisakis simplex s.l., A. physeteris, Anisakis sp. PB-2010 (Nematoda: Anisakidae, and Bolbosoma sp. (Acanthocephala: Polymorphidae. These parasite species point to the existence of three blackspot seabream stocks in the northeast Atlantic: one in the Azores region (ICES Area X, one in continental Portuguese shelf/slope waters (ICES Area IXa, and one in the waters around Madeira (sub-area 1.2 of FAO 34, central-eastern Atlantic.

  10. Shelf-life extension of gilthead seabream fillets by osmotic treatment and antimicrobial agents.

    Science.gov (United States)

    Tsironi, T N; Taoukis, P S

    2012-02-01

    The objectives of the study were to evaluate the effect of selected antimicrobial agents on the shelf life of osmotically pretreated gilthead seabream and to establish reliable kinetic equations for shelf-life determination validated in dynamic conditions. Fresh gilthead seabream (Sparus aurata) fillets were osmotically treated with 50% high dextrose equivalent maltodextrin (HDM, DE 47) plus 5% NaCl and 0·5% carvacrol, 0·5% glucono-δ-lactone or 1% Citrox (commercial antimicrobial mix). Untreated and treated slices were aerobically packed and stored isothermally (0-15°C). Microbial growth and quality-related chemical indices were modelled as functions of temperature. Models were validated at dynamic storage conditions. Osmotic pretreatment with the use of antimicrobials led to significant shelf-life extension of fillets, in terms of microbial growth and organoleptic deterioration. The shelf life was 7 days for control samples at 5°C. The osmotic pretreatment with carvacrol, glucono-δ-lactone and Citrox allowed for shelf-life extension by 8, 10 and 5 days at 5°C, respectively. The results of the study show the potential of adding carvacrol, glucono-δ-lactone or Citrox in the osmotic solution to extend the shelf life and improve commercial value of chilled osmotically pretreated fish products. The developed models can be a reliable tool for predicting the shelf life of fresh or minimally processed gilthead seabream fillets in the real chill chain. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  11. Nutritional mitigation of winter thermal stress in gilthead seabream: Associated metabolic pathways and potential indicators of nutritional state.

    Science.gov (United States)

    Richard, Nadège; Silva, Tomé S; Wulff, Tune; Schrama, Denise; Dias, Jorge P; Rodrigues, Pedro M L; Conceição, Luís E C

    2016-06-16

    A trial was carried out with gilthead seabream juveniles, aiming to investigate the ability of an enhanced dietary formulation (diet Winter Feed, WF, containing a higher proportion of marine-derived protein sources and supplemented in phospholipids, vitamin C, vitamin E and taurine) to assist fish in coping with winter thermal stress, compared to a low-cost commercial diet (diet CTRL). In order to identify the metabolic pathways affected by WF diet, a comparative two dimensional differential in-gel electrophoresis (2D-DIGE) analysis of fish liver proteome (pH 4–7) was undertaken at the end of winter. A total of 404 protein spots, out of 1637 detected, were differentially expressed between the two groups of fish. Mass spectrometry analysis of selected spots suggested that WF diet improved oxidative stress defense, reduced endoplasmic reticulum stress, enhanced metabolic flux through methionine cycle and phenylalanine/tyrosine catabolism, and induced higher aerobic metabolism and gluconeogenesis. Results support the notion that WF diet had a positive effect on fish nutritional state by partially counteracting the effect of thermal stress and underlined the sensitivity of proteome data for nutritional and metabolic profiling purposes. Intragroup variability and co-measured information were also used to pinpoint which proteins displayed a stronger relation with fish nutritional state. Winter low water temperature is a critical factor for gilthead seabream farming in the Mediterranean region, leading to a reduction of feed intake, which often results in metabolic and immunological disorders and stagnation of growth performances. In a recent trial, we investigated the ability of an enhanced dietary formulation (diet WF) to assist gilthead seabream in coping with winter thermal stress, compared to a standard commercial diet (diet CTRL). Within this context, in the present work, we identified metabolic processes that are involved in the stress-mitigating effect observed

  12. Movements of Diplodus sargus (Sparidae) within a Portuguese coastal Marine Protected Area: Are they really protected?

    Science.gov (United States)

    Belo, Ana Filipa; Pereira, Tadeu José; Quintella, Bernardo Ruivo; Castro, Nuno; Costa, José Lino; de Almeida, Pedro Raposo

    2016-03-01

    Mark-recapture tagging and acoustic telemetry were used to study the movements of Diplodus sargus within the Pessegueiro Island no-take Marine Protected Area (MPA), (Portugal) and assess its size adequacy for this species' protection against fishing activities. Therefore, 894 Diplodus sargus were captured and marked with conventional plastic t-bar tags. At the same time, 19 D. sargus were tagged with acoustic transmitters and monitored by 20 automatic acoustic receivers inside the no-take MPA for 60 days. Recapture rate of conventionally tagged specimens was 3.47%, most occurring during subsequent marking campaigns. One individual however was recaptured by recreational fishermen near Faro (ca. 250 km from the tagging location) 6 months after release. Furthermore, three specimens were recaptured in October 2013 near releasing site, one year after being tagged. Regarding acoustic telemetry, 18 specimens were detected by the receivers during most of the study period. To analyse no-take MPA use, the study site was divided into five areas reflecting habitat characteristics, three of which were frequently used by the tagged fish: Exterior, Interior Protected and Interior Exposed areas. Information on no-take protected area use was also analysed according to diel and tidal patterns. Preferred passageways and permanence areas were identified and high site fidelity was confirmed. The interaction between tide and time of day influenced space use patterns, with higher and more variable movements during daytime and neap tides. This no-take MPA proved to be an important refuge and feeding area for this species, encompassing most of the home ranges of tagged specimens. Therefore, it is likely that this no-take MPA is of adequate size to protect D. sargus against fishing activities, thus contributing to its sustainable management in the region. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Survival of fish after escape from a 40 mm stretched diamond mesh trawl codend in the Aegean Sea

    Directory of Open Access Journals (Sweden)

    Faik Ozan Düzbastilar

    2010-11-01

    Full Text Available This study aimed to determine the survival rates of three fish species, the brown comber (Serranus hepatus, black goby (Gobius niger and annular seabream (Diplodus annularis, after their escape from a 40 mm stretched diamond mesh polyethylene (PE codend. Experiments were carried out in the eastern Mediterranean in September 2007 using a conventional bottom trawl with 600 meshes around the mouth. A constant 15 min towing duration was used for all hauls. The towing speed varied between 2.0 and 2.5 knots. Codend covers, supported by two hoops, were used to retain escaping fish. At the end of each haul, these covers were detached from the codend, fixed to the sea floor at depths of 19 to 28 m, and then observed by the divers for a period of seven days. On the eighth day, all of the covers were lifted up and the survivors and mortalities were counted and measured. The mean survival percentages of open codend and experimental cages were found to be 97.1% and 98.3% for brown comber, 69.0% and 77.2% for black goby, and 97.5% and 98.6% for annular seabream respectively.

  14. Monospecies and multispecies probiotic formulations produce different systemic and local immunostimulatory effects in the gilthead seabream (Sparus aurata L.).

    Science.gov (United States)

    Salinas, Irene; Abelli, Luigi; Bertoni, Fabrizio; Picchietti, Simona; Roque, Ana; Furones, Dolors; Cuesta, Alberto; Meseguer, José; Esteban, Maria Angeles

    2008-07-01

    The effects of the oral administration of heat-inactivated Lactobacillus delbrüeckii ssp. lactis and Bacillus subtilis, individually or combined, on gilthead seabream immune responses were investigated both systemically and locally in the gut. In a first experiment, seabream (65 g) were fed for 3 weeks different diets supplemented with 1 x 10(7)CFU g(-1)Lactobacillus, 1 x 10(7)CFU g(-1)Bacillus, or 0.5 x 10(7)CFU g(-1)Lactobacillus plus 0.5 x 10(7)CFU g(-1)Bacillus. Controls were fed non-supplemented diet. Six fish per group were sampled at the end of the trial and some humoral and cellular systemic innate immune parameters were evaluated. Feeding the mixture of the two killed bacteria species significantly increased natural complement, serum peroxidase and phagocytic activities compared with controls. In a second experiment, juvenile seabream (13 g) were fed for 3 weeks the same experimental diets and total serum IgM and numbers of gut IgM(+) cells and acidophilic granulocytes were evaluated. All these parameters were significantly higher in the multispecies probiotic group compared to monospecies and control fed groups. The advantages provided by administration of killed probiotic bacteria as well as multispecies versus monospecies formulations are discussed in light of the results obtained and for their possible application in aquacultural practices.

  15. Environmental conditioning of skeletal anomalies typology and frequency in gilthead seabream (Sparus aurata L., 1758 juveniles.

    Directory of Open Access Journals (Sweden)

    Loredana Prestinicola

    Full Text Available In this paper, 981 reared juveniles of gilthead seabream (Sparus aurata were analysed, 721 of which were from a commercial hatchery located in Northern Italy (Venice, Italy and 260 from the Hellenic Center for Marine Research (Crete, Greece. These individuals were from 4 different egg batches, for a total of 10 different lots. Each egg batch was split into two lots after hatching, and reared with two different methodologies: intensive and semi-intensive. All fish were subjected to processing for skeletal anomaly and meristic count analysis. The aims involved: (1 quantitatively and qualitatively analyzing whether differences in skeletal elements arise between siblings and, if so, what they are; (2 investigating if any skeletal bone tissue/ossification is specifically affected by changing environmental rearing conditions; and (3 contributing to the identification of the best practices for gilthead seabream larval rearing in order to lower the deformity rates, without selections. The results obtained in this study highlighted that: i in all the semi-intensive lots, the bones having intramembranous ossification showed a consistently lower incidence of anomalies; ii the same clear pattern was not observed in the skeletal elements whose ossification process requires a cartilaginous precursor. It is thus possible to ameliorate the morphological quality (by reducing the incidence of severe skeletal anomalies and the variability in meristic counts of dermal bones of reared seabream juveniles by lowering the stocking densities (maximum 16 larvae/L and increasing the volume of the hatchery rearing tanks (minimum 40 m(3. Feeding larvae with a wide variety of live (wild preys seems further to improve juvenile skeletal quality. Additionally, analysis of the morphological quality of juveniles reared under two different semi-intensive conditions, Mesocosm and Large Volumes, highlighted a somewhat greater capacity of Large Volumes to significantly augment the

  16. Acoustic Conditioning System Development and Conditioning Experiments on Black Seabreams in the Xiangshan Bay Sea Ranch

    Science.gov (United States)

    Hu, Qingsong; Rahman, Hafiz Abd ur; Jiang, Yazhou; Zhang, Shouyu; Shentu, Jikang

    2018-06-01

    Attracting released hatchery-reared fish to designated areas during the growth process is vital to realize the objectives of sea ranching. Based on the bottom artificial reefs and surface kelp culture facilities in the Xiangshan Bay sea ranch, we proposed systematic techniques related to acoustic conditioning of the black seabream ( Sparus macrocephalus). Experiments conducted in 12 m × 10 m × 1.6 m ponds on Xixuan Island showed that black seabream was positively sensitive to 500-600 Hz periodic signals. Conditioned responses were apparent after 8 d. Two to three days were required for recovery of the memory of a conditioned response after a 20-day interval. According to the practical application requirements in the open sea, unattended acoustic conditioning equipment was developed. The ranching equipment was used in 12 m × 12 m × 2.5 m cages, and the behavior of black seabream juveniles was successfully guided after 7 days. Of the 16000 released fish, 82.5% of them were conditioned with a flexible grading net. To avoid inducing a stress response, the juveniles were released into the sea ranch in situ from the net cage. The acoustic conditioning equipments were moved into the open sea and the aggregation phenomenon of the released fish was observed when the sound was played. After 6 months of investigation and based on Sr+ marking, only one acoustically conditioned fish was found outside the 3.5-km2 sea ranch area, thereby reached the goal of guiding activity. The practical effect in the Xiangshan Bay sea ranch showed the validity of the acoustic conditioning system, which may contribute to improve the operation of the sea ranches in the East China Sea.

  17. Potencies of red seabream AHR1- and AHR2-mediated transactivation by dioxins: implication of both AHRs in dioxin toxicity.

    Science.gov (United States)

    Bak, Su-Min; Iida, Midori; Hirano, Masashi; Iwata, Hisato; Kim, Eun-Young

    2013-03-19

    To evaluate species- and isoform-specific responses to dioxins and related compounds (DRCs) via aryl hydrocarbon receptor (AHR) in the red seabream ( Pagrus major ), we constructed a reporter gene assay system. Each expression plasmid of red seabream AHR1 (rsAHR1) and AHR2 (rsAHR2) together with a reporter plasmid containing red seabream CYP1A 5'-flanking region were transfected into COS-7 cells. The cells were treated with graded concentrations of seven DRC congeners including 2,3,7,8-TCDD, 1,2,3,7,8-PeCDD, 1,2,3,4,7,8-HxCDD, 2,3,7,8-TCDF, 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, and PCB126. Both rsAHR1 and rsAHR2 exhibited dose-dependent responses for all the tested congeners. The rsAHR isoform-specific TCDD induction equivalency factors (rsAHR1- and rsAHR2-IEFs) were calculated on the basis of 2,3,7,8-TCDD relative potency derived from the dose-response of each congener. The rsAHR1-IEFs of PeCDD, HxCDD, TCDF, PeCDF, and HxCDF were estimated as 0.17, 0.29, 2.5, 1.5, and 0.27, respectively. For PCB126, no rsAHR1-IEF was given because of less than 10% 2,3,7,8-TCDD maximum response. The rsAHR2-IEFs of PeCDD, HxCDD, TCDF, PeCDF, HxCDF, and PCB126 were estimated as 0.38, 0.13, 1.5, 0.93, 0.20, and 0.0085, respectively. The rsAHR1/2-IEF profiles were different from WHO toxic equivalency factors for fish. In silico docking simulations supported that both rsAHRs have potentials to bind to these congeners. These results suggest that dioxin toxicities may be mediated by both rsAHRs in red seabreams.

  18. Genotoxicity of gemfibrozil in the gilthead seabream (Sparus aurata).

    Science.gov (United States)

    Barreto, A; Luis, L G; Soares, A M V M; Paíga, P; Santos, L H M L M; Delerue-Matos, C; Hylland, K; Loureiro, S; Oliveira, M

    2017-09-01

    Widespread use of pharmaceuticals and suboptimal wastewater treatment have led to increased levels of these substances in aquatic ecosystems. Lipid-lowering drugs such as gemfibrozil, which are among the most abundant human pharmaceuticals in the environment, may have deleterious effects on aquatic organisms. We examined the genotoxicity of gemfibrozil in a fish species, the gilthead seabream (Sparus aurata), which is commercially important in southern Europe. Following 96-h waterborne exposure, molecular (erythrocyte DNA strand breaks) and cytogenetic (micronuclei and other nuclear abnormalities in cells) endpoints were measured. Gemfibrozil was positive in both endpoints, at environmentally relevant concentrations, a result that raises concerns about the potential genotoxic effects of the drug in recipient waters. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Influence of supplemental maslinic acid (olive-derived triterpene) on the post-mortem muscle properties and quality traits of gilthead seabream

    DEFF Research Database (Denmark)

    Matos, E.; Silva, Tomé Santos; Wulff, Tune

    2013-01-01

    , enzymatic activities and protein expression in the muscle were assessed. Supplementing gilthead seabream diets with maslinic acid mainly resulted in hypertrophy of muscle fibres and inhibition of cathepsin B activity, with no observed differences in terms of glycogen and ATP content of the muscle, as well...... as glycogen phosphorylase activity. Proteomic analysis showed a low impact of maslinic acid supplementation on muscle metabolism, with most changes reflecting increased stress coping capacity and muscle hypertrophy in maslinic acid-fed fish. As a finishing strategy to improve the muscle's energetic status......Maslinic acid, a natural triterpene, was evaluated as a dietary supplement to modulate glycogen post-mortem mobilization in gilthead seabream muscle. For this purpose, a multidisciplinary trial was undertaken, where flesh quality criteria, as well as biochemical and histological parameters...

  20. Dietary Tools To Modulate Glycogen Storage in Gilthead Seabream Muscle: Glycerol Supplementation

    DEFF Research Database (Denmark)

    Silva, Tomé S.; Matos, Elisabete; Cordeiro, Odete D.

    2012-01-01

    The quality and shelf life of fish meat products depend on the skeletal muscle’s energetic state at slaughter, as meat decomposition processes can be exacerbated by energy depletion. In this study, we tested dietary glycerol as a way of replenishing muscle glycogen reserves of farmed gilthead......, and organoleptic properties (aroma and color). Proteomic analysis showed a low impact of glycerol-supplementation on muscle metabolism, with most changes probably reflecting increased stress coping capacity in glycerol-fed fish. This suggests inclusion of crude glycerol in gilthead seabream diets (particularly...

  1. Effects of dietary inulin and heat-inactivated Bacillus subtilis on gilthead seabream (Sparus aurata L.) innate immune parameters.

    Science.gov (United States)

    Cerezuela, R; Cuesta, A; Meseguer, J; Esteban, M A

    2012-03-01

    In the present study, a feeding trial was conducted to evaluate the effect of inulin and heat-inactivated Bacillus subtilis, single or combined, on several innate immune activities of gilthead seabream (Sparus aurata). Forty-eight specimens were randomly assigned to four dietary treatments: 0 (control), inulin (10 g/kg, prebiotic group), B. subtilis (10(7) cfu/g, probiotic group), or B. subtilis + inulin (10(7) cfu/g + 10 g/kg, synbiotic group). After two and four weeks, six fish of each group were sampled, with the main innate immune parameters (natural haemolytic complement activity, serum and leucocyte peroxidase, phagocytosis, respiratory burst, and cytotoxic activities) being determined. Inulin or heat-inactivated B. subtilis failed to significantly stimulate the innate immune parameters assayed, although some activities showed no significant increase through these treatments. A combination of inulin and B. subtilis resulted in an increase of such parameters, with the haemolytic complement activity being the only one significantly stimulated. To conclude, inulin and B. subtilis, when administered as a synbiotic, have a synergistic effect and enhance some innate immune parameters of gilthead seabream.

  2. Diel activity and variability in habitat use of white sea bream in a temperate marine protected area.

    Science.gov (United States)

    Di Lorenzo, Manfredi; Fernández, Tomás Vega; Badalamenti, Fabio; Guidetti, Paolo; Starr, Richard M; Giacalone, Vincenzo Maximiliano; Di Franco, Antonio; D'Anna, Giovanni

    2016-05-01

    Fish populations are often comprised of individuals that use habitats and associated resources in different ways. We placed sonic transmitters in, and tracked movements of, white sea bream (Diplodus sargus sargus) in the no-take zone of a Mediterranean marine protected area: the Torre Guaceto marine protected area, (Adriatic Sea, Italy). Tagged fish displayed three types of diel activity patterns in three different habitats: sand, rocky reefs and "matte" of the seagrass Posidonia oceanica. Individuals were more active during the day than at night. Overall, white sea bream displayed a remarkable behavioural plasticity in habitat use. Our results indicate that the observed behavioural plasticity in the marine protected area could be the result of multiple ecological and environmental drivers such as size, sex and increased intra-specific competition. Our findings support the view that habitat diversity helps support high densities of fishes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Fish energy budget under ocean warming and flame retardant exposure.

    Science.gov (United States)

    Anacleto, Patrícia; Figueiredo, Cátia; Baptista, Miguel; Maulvault, Ana Luísa; Camacho, Carolina; Pousão-Ferreira, Pedro; Valente, Luísa M P; Marques, António; Rosa, Rui

    2018-07-01

    Climate change and chemical contamination are global environmental threats of growing concern for the scientific community and regulatory authorities. Yet, the impacts and interactions of both stressors (particularly ocean warming and emerging chemical contaminants) on physiological responses of marine organisms remain unclear and still require further understanding. Within this context, the main goal of this study was to assess, for the first time, the effects of warming (+ 5 °C) and accumulation of a polybrominated diphenyl ether congener (BDE-209, brominated flame retardant) through dietary exposure on energy budget of the juvenile white seabream (Diplodus sargus). Specifically, growth (G), routine metabolism (R), excretion (faecal, F and nitrogenous losses, U) and food consumption (C) were calculated to obtain the energy budget. The results demonstrated that the energy proportion spent for G dominated the mode of the energy allocation of juvenile white seabream (56.0-67.8%), especially under the combined effect of warming plus BDE-209 exposure. Under all treatments, the energy channelled for R varied around 26% and a much smaller percentage was channelled for excretion (F: 4.3-16.0% and U: 2.3-3.3%). An opposite trend to G was observed to F, where the highest percentage (16.0 ± 0.9%) was found under control temperature and BDE-209 exposure via diet. In general, the parameters were significantly affected by increased temperature and flame retardant exposure, where higher levels occurred for: i) wet weight, relative growth rate, protein and ash contents under warming conditions, ii) only for O:N ratio under BDE-209 exposure via diet, and iii) for feed efficiency, ammonia excretion rate, routine metabolic rate and assimilation efficiency under the combination of both stressors. On the other hand, decreased viscerosomatic index was observed under warming and lower fat content was observed under the combined effect of both stressors. Overall, under future

  4. On the record of Red seabream Pagrus major (Temminck and Schlegel,1843 (Osteichthyes: Sparidae in the Adriatic Sea

    Directory of Open Access Journals (Sweden)

    Jakov Dulcic

    2007-03-01

    Full Text Available One specimen of red seabream Pagrus major, 44.9 cm total length, was caught in the eastern middle Adriatic (Island Molat, Cape Bonaster by long-line hook at a depth of about 20 m on a hard rocky bottom on 25 September 2004. It is the first record of this species in the Adriatic Sea and Mediterranean area.

  5. Prebiotics effect on immune and hepatic oxidative status and gut morphology of white sea bream (Diplodus sargus).

    Science.gov (United States)

    Guerreiro, Inês; Couto, Ana; Machado, Marina; Castro, Carolina; Pousão-Ferreira, Pedro; Oliva-Teles, Aires; Enes, Paula

    2016-03-01

    The aim of this study was to evaluate the effects of short-chain fructooligosaccharides (scFOS), xylooligosaccharides (XOS) and galactooligosaccharides (GOS) on immune and hepatic oxidative status, and gut morphology of white sea bream juveniles. Four diets were formulated: a control diet with fish meal (FM) and plant feedstuffs (PF) (30FM:70PF) and three test diets similar to the control but supplemented with 1% of scFOS, XOS or GOS. Dietary prebiotic incorporation did not affect total blood cell counts, hematocrit, hemoglobin, red blood indices or differential white blood cell counts. Fish fed GOS had lower ACH50 and nitric oxide than fish fed control diet. XOS enhanced immune status through the increase in alternative complement pathway (ACH50), lysozyme and total immunoglobulin. The higher activity of glucose 6-phosphate dehydrogenase in fish fed FOS compared to the other dietary groups was the only related antioxidant enzyme affected by prebiotics in the liver. GOS ameliorated the precocious adverse effects of PF based diet on gut histomorphology, as denoted by the lower incidence of histological alterations in fish fed GOS for 15 days. In conclusion, XOS and GOS at 1% might have potential to be used as prebiotics in white sea bream juveniles. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Oral delivery of live yeast Debaryomyces hansenii modulates the main innate immune parameters and the expression of immune-relevant genes in the gilthead seabream (Sparus aurata L.).

    Science.gov (United States)

    Reyes-Becerril, Martha; Salinas, Irene; Cuesta, Alberto; Meseguer, José; Tovar-Ramirez, Dariel; Ascencio-Valle, Felipe; Esteban, Maria Angeles

    2008-12-01

    Microorganisms isolated from fish can be used as prophylactic tools for aquaculture in the form of probiotic preparations. The purpose of this study was to evaluate the effects of dietary administration of the live yeast Debaryomyces hansenii CBS 8339 on the gilthead seabream (Sparus aurata L.) innate immune responses. Seabream were fed control or D. hansenii-supplemented diets (10(6) colony forming units, CFU g(-1)) for 4 weeks. Humoral (seric alternative complement and peroxidase activities), and cellular (peroxidase, phagocytic, respiratory burst and cytotoxic activities) innate immune parameters and antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)) were measured from serum, head-kidney leucocytes and liver, respectively, after 2 and 4 weeks of feeding. Expression levels of immune-associated genes, Hep, IgM, TCR-beta, NCCRP-1, MHC-II alpha, CSF-1R, C3, TNF-alpha and IL-1 beta, were also evaluated by real-time PCR in head-kidney, liver and intestine. Humoral immune parameters were not significantly affected by the dietary supplementation of yeast at any time of the experiment. On the other hand, D. hansenii administration significantly enhanced leucocyte peroxidase and respiratory burst activity at week 4. Phagocytic and cytotoxic activities had significantly increased by week 2 of feeding yeast but unchanged by week 4. A significant increase in liver SOD activity was observed at week 2 of feeding with the supplemented diet; however CAT activity was not affected by the dietary yeast supplement at any time of the experiment. Finally, the yeast supplemented diet down-regulated the expression of most seabream genes, except C3, in liver and intestine and up-regulated all of them in the head-kidney. These results strongly support the idea that live yeast Debaryomyces hansenii strain CBS 8339 can stimulate the innate immune parameters in seabream, especially at cellular level.

  7. Effect of Phenanthrene on the Tissue Structure of Liver and Aminotransferase Enzymes in Yellowfin Seabream (Acanthopagrus latus

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    Mehrnaz Shirmohammadi*

    2017-06-01

    Full Text Available Background: Polycyclic aromatic hydrocarbons (PAHs such as phenanthrene (Phe represent one of the most abundant forms of organic pollutants. The aim of this study was to assess changes in plasma levels of aminotransferase enzymes, total protein and liver tissue as biomarkers of yellowfin seabream (Acanthopagrus latus exposed to Phe for 14 d. Methods: The research was carried out in January 2016 at Khorramshahr University of Marine Sciences and Technology, Khorramshahr, Iran. Some 72 fish were injected with 2, 20, 40 and 70 mg/kg of Phe. Then tissue and blood samples were obtained at 1, 4, 7 and 14 d after injection. Results: Exposure of fish to Phe resulted in a significant increase of alanine aminotransferase (ALT, aspartate aminotransferase (AST and decrease of total protein after 7 d of the experiment (P<0.05. The main histopathological alteration was showed in different sampling days including nucleus margination, hypertrophy, vacuolation, melanomacrophages aggregates, sinusoid dilation, degeneration and picnotic nucleus. Degree of tissue change (DTC of liver was recorded in the Phe-exposed fish from normal range to moderate changes. Conclusion: The studied biomarkers such as changes in concentrations of ALT, AST and total protein as well as tissue damages in liver may be served as beneficial biomarker to assess Phe toxicity in yellowfin seabream.

  8. Presence of the Striped Seabream (Lithognathus mormyrus L., 1758 in the Black Sea

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    Mehmet AYDIN

    2017-11-01

    Full Text Available It is known that Mediterranean demersal species reach to the Black Sea through the Turkish Straits System and adapt to this nearly landlocked environment. In this article, the existence of Mediterranean originated striped seabream (Lithognathus mormyrus L., 1758 in the Black Sea is studied. In this study, 25 individuals were sampled in the Middle Black Sea region (Ordu – Fatsa by trammel nets. The minimum and maximum lengths of the sampled species were measured as 16 cm and 20.1 cm respectively, while the length-weight relationship can be given by the equation, W=0.0711L2.3981 (R² = 0.8171.

  9. Towards a deeper understanding of fatty acid bioaccessibility and its dependence on culinary treatment and lipid class: a case study of gilthead seabream (Sparus aurata).

    Science.gov (United States)

    Costa, Sara; Afonso, Cláudia; Cardoso, Carlos; Oliveira, Rui; Alves, Francisca; Nunes, Maria L; Bandarra, Narcisa M

    2016-11-08

    The bioaccessibility of total lipids and fatty acids (FA) in raw and grilled gilthead seabream (Sparus aurata) was determined using an in vitro digestion model. The particular impact of grilling on the FA profile of seabream was also studied. In addition, the influence of lipid class on the bioaccessibility of each FA was analysed. Grilling did not change the relative FA profile, and only the absolute values were altered. However, the relative FA profile varied across lipid classes, being more dissimilar between TAG and phospholipids. Long-chain SFA and PUFA seemed to be less bioaccessible. Moreover, grilling reduced bioaccessibility of protein, fat and many FA, with the highest reductions found in PUFA such as the DHA. Strong evidence supporting a predominantly regioselective action of lipase during in vitro digestion was found, and the impact of this phenomenon on FA bioaccessibility was assessed.

  10. Assessment of the Scales of Gilthead Seabream (Sparus aurata L. by Image Analysis and Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Francisco Casado

    2018-01-01

    Full Text Available Understanding the protective role of fish skin is critical to improving the development of aquaculture, since skin is the main surface that separates the animal from its always hazardous environment. Many techniques have been used for its study, but certain structural characteristics of fish skin still remain not clearly understood. That is the case with scales, which have always been attributed a mere protective role, but which are proving to have more functions than it was traditionally thought. To acquire a deeper knowledge, scales from six different regions of gilthead seabream (Sparus aurata L. were studied and measured by image analysis. Results prove that scales from the base of the dorsal fin are larger than those in other parts of the fish body while scales from the peduncle are the smallest of the skin. Furthermore, a technique relatively new in this field, known as atomic force microscopy (AFM, was used to obtain representations of the ultrastructure of the scales and measure certain features such as the circuli and the lines in the basal layer. The data obtained allowed us to compare the height of circuli among the different scales, showing that they were higher in scales from the dorsum and the operculum. The present results introduce a nanostructural model of the scales of gilthead seabream that might serve as a useful guideline for future studies.

  11. 1H NMR Spectroscopy and MVA Analysis of Diplodus sargus Eating the Exotic Pest Caulerpa cylindracea.

    Science.gov (United States)

    De Pascali, Sandra A; Del Coco, Laura; Felline, Serena; Mollo, Ernesto; Terlizzi, Antonio; Fanizzi, Francesco P

    2015-06-05

    The green alga Caulerpa cylindracea is a non-autochthonous and invasive species that is severely affecting the native communities in the Mediterranean Sea. Recent researches show that the native edible fish Diplodus sargus actively feeds on this alga and cellular and physiological alterations have been related to the novel alimentary habits. The complex effects of such a trophic exposure to the invasive pest are still poorly understood. Here we report on the metabolic profiles of plasma from D. sargus individuals exposed to C. cylindracea along the southern Italian coast, using 1H NMR spectroscopy and multivariate analysis (Principal Component Analysis, PCA, Orthogonal Partial Least Square, PLS, and Orthogonal Partial Least Square Discriminant Analysis, OPLS-DA). Fish were sampled in two seasonal periods from three different locations, each characterized by a different degree of algal abundance. The levels of the algal bisindole alkaloid caulerpin, which is accumulated in the fish tissues, was used as an indicator of the trophic exposure to the seaweed and related to the plasma metabolic profiles. The profiles appeared clearly influenced by the sampling period beside the content of caulerpin, while the analyses also supported a moderate alteration of lipid and choline metabolism related to the Caulerpa-based diet.

  12. Seasonal expression of arginine vasotocin mRNA and its correlations to gonadal steroidogenic enzymes and sexually dimorphic coloration during sex reversal in the gilthead seabream (Sparus aurata).

    Science.gov (United States)

    Reyes-Tomassini, José J; Wong, Ten-Tsao; Zohar, Yonathan

    2017-06-01

    Arginine vasotocin is a hormone produced in the hypothalamus of teleost fish that has been shown to regulate gonad development and sexual behavior. To study the role of arginine vasotocin in the gonadal cycle of the hermaphrodite gilthead seabream, Sparus aurata, we cloned the seabream arginine vasotocin (avt) complementary DNA (cDNA). We investigated the expression of brain avt throughout the gonad cycle using real-time quantitative PCR and compared its expression levels to the expression levels of two key gonadal steroidogenic enzymes, cyp19a1a and cyp11b2. In July, when the process of sex reversal is thought to begin, avt expression was elevated over the previous 2 months. Avt in the brain remained at or above the level of July until November then peaked again in December. There was no difference between males and females in the expression levels of brain avt throughout the year. However, only in ambisexual fish was the expression of the cyp19a1a gonadal aromatase correlated to the expression of avt in the brain. Cyp11b2 did not show any correlation to brain avt expression. We also found that females had more intense body coloration than males and that this intensity peaked prior to spawning. Avt expression and female coloration were positively correlated. The fact that brain avt expression was lowest during gonad quiescence, together with the observation of a correlation between brain avt with gonadal cyp19a1a and body coloration during that time suggests that avt may play a role during the process of sex reversal and spawning of the gilthead seabream.

  13. Effects of environmental enrichment on growth, aggressive behaviour and brain monoamines of gilthead seabream Sparus aurata reared under different social conditions.

    Science.gov (United States)

    Batzina, Alkisti; Dalla, Christina; Papadopoulou-Daifoti, Zeta; Karakatsouli, Nafsika

    2014-03-01

    The presence of blue or red-brown substrate on the tank bottom has been previously reported as an efficient means of environmental enrichment for gilthead seabream. The present study aimed to investigate whether this enrichment is still beneficial when gilthead seabream is reared under different social conditions (i.e. a lower 4.9 kg m(-3) and a higher 9.7 kg m(-3) density). Water exchange was adjusted according to fish biomass to exclude density effects on water quality. In the enriched tanks single-colour glass gravel was used as substrate (blue and red-brown substrate, or BS and RBS respectively), while control tanks had no gravel. Growth, aggressive behaviour and size distribution results indicated that the lower density created a less favourable social environment. In both densities studied, BS enhanced growth, suppressed aggression and reduced brain serotonergic activity. In the condition of intense social interactions (i.e. the lower density) BS also reduced brain dopaminergic activity. These results along with the negative correlations observed between brain monoamines and fish body mass, indicated that substrate and density effects are socially-induced. However, there may be several biotic and/or abiotic factors interfering with substrate effects that should be investigated before the practical use of a substrate in land-based intensive aquaculture. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Effect of seaweed supplementation on growth performance, immune and oxidative stress responses in gilthead seabream (Sparus aurata

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    Augusto Cesar dos Santos Queiroz

    2014-06-01

    Full Text Available Seaweeds have important nutraceutical properties, including antioxidant and biological response-modifying qualities. Their dietary supplementation may increase the immune and antioxidant capacity of fish necessary to cope to stressful conditions and minimizing disease outbreaks. There are essentially four major groups of seaweed that can be classified by color, namely green (Chlorophyta, brown/yellow (Phaeophyta, red (Rhodophyta, and blue-green (Cyanophyta. Some green seaweed has active radical scavenging properties. Red and brown have bioactive compounds that play a vital role as antihypertensive and antioxidant. The current study was designed to evaluate the effects of seaweed supplementation on growth performance, immune and oxidative stress responses in gilthead seabream (Sparus aurata. Three seaweed species, each from one of the following groups, Rhodophyta (R, Phaeophyta (P and Chlorophyta (C, were supplemented to the experimental diets at 2.5% and 7.5% and tested against a control diet (Ctrl with no supplementation. In addition to six diets with seaweed in two different levels of supplementation: R2.5%, P2.5%, C2.5%, R7.5%, P7.5% and C7.5%; a diet with a mix (M, supplemented at 7.5% (2.5% of each algae was also tested. A total of 360 seabream fingerlings, 13.07 ± 0.13cm and 31.17 ± 0.63g were allocated in 24 rectangular tanks, 115L capacity each, with a 4L/min water output connected to a recirculation seawater system. Fish were fed twice a day until satiation and water quality (temperature: 20.5 ºC; D.O.: 8.13 mg/L; Ammonia: 0.5 mg/L Nitrite: 0.5 mg/L were daily monitored. At day 40 of the trial, an intermediate sampling was carried out. Standard zootechnical parameters were measured for the growth performance determination. In addition, blood, liver and intestine samples were collected for the evaluation of the immune (lysozyme and peroxidase and oxidative stress (lipid peroxidation, glutathione peroxidase, glutathione reductase

  15. Cloning and molecular ontogeny of digestive enzymes in fed and food-deprived developing gilthead seabream (Sparus aurata) larvae.

    Science.gov (United States)

    Mata-Sotres, José Antonio; Martos-Sitcha, Juan Antonio; Astola, Antonio; Yúfera, Manuel; Martínez-Rodríguez, Gonzalo

    2016-01-01

    We have determined the expression pattern of key pancreatic enzymes precursors (trypsinogen, try; chymotrypsinogen, ctrb; phospholipase A2, pla2; bile salt-activated lipase, cel; and α-amylase, amy2a) during the larval stage of gilthead seabream (Sparus aurata) up to 60days after hatching (dph). Previously, complete sequences of try, cel, and amy2a were cloned and phylogenetically analyzed. One new isoform was found for cel transcript (cel1b). Expression of all enzyme precursors was detected before the mouth opening. Expression of try and ctrb increased during the first days of development and then maintained high values with some fluctuations during the whole larval stage. The prolipases pla2 and cel1b increased from first-feeding with irregular fluctuation until the end of the experiment. Contrarily, cel1a maintained low expression values during most of the larval stage increasing at the end of the period. Nevertheless, cel1a expression was negligible as compared with cel1b. The expression of amy2a sharply increased during the first week followed by a gradual decrease. In addition, a food-deprivation experiment was performed to find the differences in relation to presence/absence of gut content after the opening of the mouth. The food-deprived larvae died at 10dph. The expression levels of all digestive enzymes increased up to 7dph, declining sharply afterwards. This expression pattern up to 7dph was the same observed in fed larvae, confirming the genetic programming during the early development. Main digestive enzymes in gilthead seabream larvae exhibited the same expression profiles than other marine fish with carnivorous preferences in their juvenile stages. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. The effects of swimming pattern on the energy use of gilthead seabream (Sparus aurata L.)

    DEFF Research Database (Denmark)

    Steinhausen, Maria Faldborg; Steffensen, John Fleng; Andersen, Niels Gerner

    2010-01-01

    Oxygen consumption ( ) was measured for gilthead seabream (Sparus aurata) during spontaneous and forced activities. During spontaneous activity, the swimming pattern was analysed for the effect on   on the average speed (U), turning rate (¿) and change in speed (¿U). All swimming characteristics...... and   during forced activity was also established. During spontaneous activity, 2.5 times more energy was used than in forced swimming at a speed of 0.5 BL s-1. This indicates that spontaneous swimming costs may be considerably higher compared with those of a fixed swimming speed. However, comparing...... contributed significantly to the source of spontaneous swimming costs, and the models explained up to 58% of the variation in   Prediction of   of fish in field studies can thereby be improved if changes in speed and direction are determined in addition to swimming speed. A relationship between swimming speed...

  17. Determination and assessment of total mercury levels in local, frozen and canned fish in Lebanon.

    Science.gov (United States)

    Obeid, Pierre J; El-Khoury, Bilal; Burger, Joanne; Aouad, Samer; Younis, Mira; Aoun, Amal; El-Nakat, John Hanna

    2011-01-01

    Fish is an important constituent of the Lebanese diet. However, very little attention in our area is given to bring awareness regarding the effect of the toxicity of mercury (Hg) mainly through fish consumption. This study aimed to report analytical data on total mercury levels in several fish species for the first time in thirty years and to also made individuals aware of the presence and danger from exposure to mercury through fish consumption. Fish samples were selected from local Lebanese markets and fisheries and included 94 samples of which were fresh, frozen, processed, and canned fish. All values were reported as microgram of mercury per gram of fish based on wet weight. The level of mercury ranged from 0.0190 to 0.5700 microg/g in fresh samples, 0.0059 to 0.0665 microg/g in frozen samples, and 0.0305 to 0.1190 microg/g in canned samples. The data clearly showed that higher levels of mercury were detected in local fresh fish as opposed to other types thus placing consumers at higher risk from mercury exposure. Moreover, the data revealed that Mallifa (yellowstripe barracuda/Sphyraena chrysotaenia), Sargous (white seabream/Diplodus sargus), Ghobbos (bogue/Boops boops), and shrimp (Penaeus sp.) were among the types containing the highest amounts of mercury. On the other hand, processed fish such as fish fillet, fish burger, small shrimp and crab are found to contain lower levels of mercury and are associated with lower exposure risks to mercury. Lebanese population should therefore, be aware to consume limited amounts of fresh local fish to minimize exposure to mercury.

  18. A time course study of glucose levels and innate immune response in gilthead seabream (Sparus aurata L.) after exposure to clove oil-eugenol derived anaesthetic.

    Science.gov (United States)

    Bahi, A; Guardiola, F A; Esteban, M A

    2018-06-01

    Clove oil is used as an anaesthetic for many species of fish worldwide; however, relatively few studies have assessed its effects on the innate immune response on these species. The present work aimed to investigate the effects of clove oil-eugenol derived anaesthetic on some humoral and cellular immune response in gilthead seabream (Sparus aurata L.). To compare with an unexposed control group, fish were exposed to 55 ppm clove oil for 5 min, before being sampled at 1, 24 and 48 h post-exposure. Serum glucose level was also measured to obtain information on the fish physiological response after clove oil anaesthesia. One hour after exposure the haemolytic complement activity of fish was lower than in the unexposed group. By contrast, the leucocyte peroxidase activity in head-kidney was significantly stimulated 24 h after exposure to clove oil-eugenol. The rest of innate immune parameters evaluated and the glucose levels not were affected by clove oil exposure at any sampling point. Overall, the use of clove oil at 55 ppm as anaesthetic did not seem to alter the innate immune response and neither did it trigger a stress response. The use of clove oil-eugenol derived had become common practice in aquaculture, and its use with gilthead seabream can be considered safe as it does not cause immunodepression in anesthetized fish. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on the peripheral nervous system of developing red seabream (Pagrus major)

    Energy Technology Data Exchange (ETDEWEB)

    Iida, Midori [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Kim, Eun-Young [Department of Life and Nanopharmaceutical Science and Department of Biology, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Murakami, Yasunori [Graduate School of Science and Engineering, Ehime University, Matsuyama 790-8577 (Japan); Shima, Yasuhiro [National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, Imabari 794-2305 (Japan); Iwata, Hisato, E-mail: iwatah@agr.ehime-u.ac.jp [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan)

    2013-03-15

    We investigated 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced effects on the morphology of peripheral nervous system (PNS) in the developing red seabream (Pagrus major) embryos. The embryos at 10 h post-fertilization (hpf) were treated with 0, 0.1, 0.4 or 1.7 μg/L of TCDD in seawater for 80 min. The morphology of PNS was microscopically observed with florescence staining using an anti-acetylated tubulin antibody at 48, 78, 120 and 136 hpf. Axon length of facial nerve (VII) was found to be shortened by TCDD exposure. Axon guidance in the glossopharyngeal nerve (IX) and vagus nerve (X) was altered at 120 and 136 hpf in a TCDD dose-dependent manner. Lowest observable effect level of TCDD (0.1 μg/L) that induced the morphological alteration of PNS was lower than those of other endpoints on morphological deformities so far reported. Given that the growth cone at the tip of growing nerve axons advances under the influence of its surrounding tissues, we hypothesized that TCDD exposure would affect (1) the nerve cell proliferation/differentiation, (2) the structure of muscle as an axon target and (3) the nerve guidance factor in the embryos. By the immunostaining of embryos with an antibody against the neuronal specific RNA-binding protein, HuD, and an antibody against the sarcomeric myosin, no morphological effects were observed on the neural proliferation/differentiation and the structure of facial muscles of TCDD-treated embryos. In contrast, whole mount in situ hybridization of semaphorin 3A (Sema3A), a secretory axon repulsion factor, revealed the altered expression pattern of its transcripts in TCDD-treated embryos. Our findings suggest that TCDD treatment affects the projection of PNS in the developing red seabream embryos through the effects on the axonal growth cone guidance molecule such as Sema3A, but not on the neuronal differentiation/proliferation and axon target. The PNS in developing embryos may be one of the most sensitive biomarkers to the exposure

  20. Bycatch of crustacean and fish bottom trawl fisheries from southern Portugal (Algarve

    Directory of Open Access Journals (Sweden)

    Maria Esmeralda Costa

    2008-12-01

    Full Text Available As part of two research projects for analysing bycatch and discards, we quantified catch composition, catch rates, bycatch and discards in two important commercial bottom trawl fisheries (crustacean and fish trawls off the southern coast of Portugal (Algarve. Stratified sampling by onboard observers took place from February 1999 to March 2001 and data were collected from 165 tows during 52 fishing trips. Commercial target species included crustaceans: blue and red shrimp (Aristeus antennatus, deep-water rose shrimp (Parapenaeus longirostris, Norway lobster (Nephrops norvegicus; and fishes: seabreams (Diplodus spp. and Pagellus spp., horse mackerels (Trachurus spp. and European hake (Merluccius merluccius. The trawl fisheries are characterised by considerable amounts of bycatch: 59.5% and 80.4% of the overall total catch for crustacean and fish trawlers respectively. A total of 255 species were identified, which belonged to 15 classes of organisms (137 vertebrates, 112 invertebrates and 6 algae. Crustacean trawlers had higher bycatch biodiversity. Bony fish (45.6% and 37.8% followed by crustaceans (14.6% and 11.5% were the dominant bycatch components of both crustacean and fish trawlers respectively. The influence of a number of factors (e.g. depth, fishing gear, tow duration and season on bycatch and discards is discussed.

  1. Quantitative trait loci for a neurocranium deformity, lack of operculum, in gilthead seabream (Sparus aurata L.).

    Science.gov (United States)

    Negrín-Báez, D; Navarro, A; Afonso, J M; Toro, M A; Zamorano, M J

    2016-04-01

    Lack of operculum, a neurocranial deformity, is the most common external abnormality to be found among industrially produced gilthead seabream (Sparus aurata L.), and this entails significant financial losses. This study conducts, for the first time in this species, a quantitative trait loci (QTL) analysis of the lack of operculum. A total of 142 individuals from a paternal half-sibling family (six full-sibling families) were selected for QTL mapping. They had previously shown a highly significant association with the prevalence of lack of operculum in a segregation analysis. All the fish were genotyped for 106 microsatellite markers using a set of multiplex PCRs (ReMsa1-ReMsa13). A linear regression methodology was used for the QTL analysis. Four QTL were detected for this deformity, two of which (QTLOP1 and QTLOP2) were significant. They were located at LG (linkage group) nine and LG10 respectively. Both QTL showed a large effect (about 27%), and furthermore, the association between lack of operculum and sire allelic segregation observed was statistically significant in the QTLOP1 analysis. These results represent a significant step towards including marker-assisted selection for this deformity in genetic breeding programmes to reduce the incidence of the deformity in the species. © 2016 Stichting International Foundation for Animal Genetics.

  2. Assessment of Skin Pathological Responses in the Yellowfin Seabream (Acanthopagrus latus under the Aeromonas hydrophila Exposure

    Directory of Open Access Journals (Sweden)

    Fatemeh Azadbakht

    2018-01-01

    Full Text Available Background: Bacterial diseases in cultured fish are considered the main problem to aquaculture system. Skin is the structure that covers the body in fish. Skin histopatological alterations were used to assess the effects of Aeromonas hydrophila exposure on the yellowfin seabream Acanthopagrus latus(. Methods: In this regard, 90 A. latus were exposed to sublethal concentrations of A. hydrophila (103,106 CFU/ml for 3 weeks. Results: Some more severe alternations found in the skin of fish exposed. The most frequent histopathological changes detected in the skin including hyperplasia of epidermis, hypertrophy and hyperplasia of the mucosal cells and dermis edema. Some more severe alternations found in the skin of fish exposed to higher level of A. hydrophila (106 CFU/ml included telangiectasia of dermis layer. In addition, according to the results of histometrical studies in treated fish compared to control group showed that thickness of epidermis and dermis layers were increased significantly (P<0.05. Conclusion: A. hydrophila can cause major histophatological changes in the skin of A. latus. In addition, histopathological changes of the skin provide helpful information about the environmental conditions and as particular biomarkers may provide imminent into evaluating the general health and stress status of fish.

  3. The ecological significance of juvenile Diplodus sargus as ectoparasite fish cleaners in the north-eastern Atlantic

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    José Neto

    2015-11-01

    Full Text Available Cleaning behaviour was recently described for the omnivorous species Diplodus sargus. Although previous studies have reported the existence of ectoparasites in the stomach contents of some individuals this commercially important fish was never considered a cleaner species. Here we make the first characterization of this behaviour based on field observations. This behaviour was exclusively performed by juvenile D. sargus and, until now, was only observed in confined or semi-confined areas such as coastal lagoons or harbours. Unexpectedly, cleaning rates and the number of individuals performing this behaviour largely exceeds the ones described for a sympatric cleaner fish (13.98 cleaning events/individual/hour compared to 5.08 in Centrolabrus exoletus. Clients belong to several fish families (e.g. Mugilidae, Sparidae and Labridae that include some of the most common species in coastal habitats. Frequently, clients request cleaning by tilting their body or remaining motionless near the surface while being cleaned (40% however, in most cases, the interaction ends because clients flee (46%. This could mean that D. sargus is also feeding on mucus and/or living tissue. These shifts between exploitation and cooperation have been frequently described for tropical reef species. Our results support cooperative behaviour, with a clear correlation between the number of nips per cleaning event or the number of nips to which the client reacted positively and cleaning event duration (n=552; Spearman correlation r=0.79, p<0.001; r=0.76, p<0.001, respectively. Furthermore, no correlation was detected between the number of jolts by the client fish and the cleaning event duration (n=552; Spearman correlation r=0.07, p=0.105 meaning that jolting does not increase with increased interaction time. In the future, the evaluation of the ecological importance of D. sargus as a cleaner species in the North-Eastern Atlantic, should proceed with field observations in

  4. Identifying some pathogenic Vibrio/Photobacterium species during mass mortalities of cultured Gilthead seabream (Sparus aurata and European seabass (Dicentrarchus labrax from some Egyptian coastal provinces

    Directory of Open Access Journals (Sweden)

    Mohammed Abdel-Aziz

    2013-12-01

    Full Text Available Vibrio alginolyticus, Vibrio parahemolyticus and Photobacterium damselae subsp damselae were isolated during recurrent episodes of mass mortalities among different stages of Gilthead sea bream (Sparus aurata and European seabass (Dicentrarchus labrax. The pathogens were recovered from the external/internal lesions of a total of 320 seeds, juvenile and adult fishes from the period of February 2013 through August 2013. Two hundred and sixty four bacterial isolates were retrieved and presumptively identified using morpho-chemical characterization and API®20NE. However, definitive molecular confirmation of V. alginolyticus was obtained through implementing collagenase gene based regular PCR technique. The total prevalence of V. alginolyticus, V. parahemolyticus and Photobacterium damselae subsp damselae among naturally infected Gilthead seabream and European seabass was 82.19%, 87.28% 10.27%, 6.79% and 7.54%, 5.93% respectively. Antibiogram has revealed that isolates were sensitive to ciprofloxacin, chloramphenicol, enrofloxacin, nalidixic acid and oxolinic acid while resistant to ampicillin, amoxicillin, and lincomycin.

  5. Proteomic profile of the skin mucus of farmed gilthead seabream (Sparus aurata).

    Science.gov (United States)

    Jurado, Juan; Fuentes-Almagro, Carlos A; Guardiola, Francisco Antonio; Cuesta, Alberto; Esteban, Ma Ángeles; Prieto-Álamo, María-José

    2015-04-29

    Fish skin mucus is the first line of defense against infections and it discriminates between pathogenic and commensal bacterial strains. Mucus composition varies amongst fish species and is influenced by endogenous and exogenous factors. This study describes the first proteome map of the epidermal mucus of farmed gilthead seabream (Sparus aurata). We used an integrative proteomic approach by combining a label-free procedure (LC-MS/MS) with the classical 2-DE-PMF-MS/MS methodology. The identified mucosal proteins were clustered in four groups according to their biological functions. Structural proteins (actins, keratins, tubulins, tropomyosin, cofilin-2 and filamin-A) and metabolic proteins (ribosomal proteins, proteasomal subunits, NACA, VCP, histones, NDPK, transferrin, glycolytic enzymes, ATP synthase components, beta-globin, Apo-A1 and FABP7) were the best represented functional categories. We also found proteins involved in stress response (WAP65, HSPC70, Cu,Zn-SOD, and PRDX1 and PRDX2) and signal transduction (PP2A 65kDa regulatory subunit, 14-3-3 protein beta/alpha, tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, RhoGDI and PEBP1). Most of the identified proteins address different aspects of the innate immune response. Additionally, we analyzed bacterial peptides identified in the skin mucus of healthy S. aurata. These results revealed that genera belonging to the Lactobacillales order constitute the most abundant microorganism populations in this habitat. This work shows that proteomic methods can be used to characterize fish skin mucus. Using a coupled approach of LC-MS/MS and a 2-DE-PMF-MS/MS, we have obtained the first comprehensive view of the skin mucosal proteome of S. aurata, a fish species that is economically relevant for Mediterranean aquaculture. We identified a panel of proteins involved in a variety of biological functions, particularly in the innate immune response. Furthermore, to our knowledge, this is the first time a

  6. Diet of bottlenose dolphins (Tursiops truncatus from the Gulf of Cadiz: Insights from stomach content and stable isotope analyses.

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    Joan Giménez

    Full Text Available The ecological role of species can vary among populations depending on local and regional differences in diet. This is particularly true for top predators such as the bottlenose dolphin (Tursiops truncatus, which exhibits a highly varied diet throughout its distribution range. Local dietary assessments are therefore critical to fully understand the role of this species within marine ecosystems, as well as its interaction with important ecosystem services such as fisheries. Here, we combined stomach content analyses (SCA and stable isotope analyses (SIA to describe bottlenose dolphins diet in the Gulf of Cadiz (North Atlantic Ocean. Prey items identified using SCA included European conger (Conger conger and European hake (Merluccius merluccius as the most important ingested prey. However, mass-balance isotopic mixing model (MixSIAR, using δ13C and δ15N, indicated that the assimilated diet consisted mainly on Sparidae species (e.g. seabream, Diplodus annularis and D. bellottii, rubberlip grunt, Plectorhinchus mediterraneus, and common pandora, Pagellus erythrinus and a mixture of other species including European hake, mackerels (Scomber colias, S. japonicus and S. scombrus, European conger, red bandfish (Cepola macrophthalma and European pilchard (Sardina pilchardus. These contrasting results highlight differences in the temporal and taxonomic resolution of each approach, but also point to potential differences between ingested (SCA and assimilated (SIA diets. Both approaches provide different insights, e.g. determination of consumed fish biomass for the management of fish stocks (SCA or identification of important assimilated prey species to the consumer (SIA.

  7. Using an integral projection model to assess the effect of temperature on the growth of gilthead seabream Sparus aurata.

    Science.gov (United States)

    Heather, F J; Childs, D Z; Darnaude, A M; Blanchard, J L

    2018-01-01

    Accurate information on the growth rates of fish is crucial for fisheries stock assessment and management. Empirical life history parameters (von Bertalanffy growth) are widely fitted to cross-sectional size-at-age data sampled from fish populations. This method often assumes that environmental factors affecting growth remain constant over time. The current study utilized longitudinal life history information contained in otoliths from 412 juveniles and adults of gilthead seabream, Sparus aurata, a commercially important species fished and farmed throughout the Mediterranean. Historical annual growth rates over 11 consecutive years (2002-2012) in the Gulf of Lions (NW Mediterranean) were reconstructed to investigate the effect of temperature variations on the annual growth of this fish. S. aurata growth was modelled linearly as the relationship between otolith size at year t against otolith size at the previous year t-1. The effect of temperature on growth was modelled with linear mixed effects models and a simplified linear model to be implemented in a cohort Integral Projection Model (cIPM). The cIPM was used to project S. aurata growth, year to year, under different temperature scenarios. Our results determined current increasing summer temperatures to have a negative effect on S. aurata annual growth in the Gulf of Lions. They suggest that global warming already has and will further have a significant impact on S. aurata size-at-age, with important implications for age-structured stock assessments and reference points used in fisheries.

  8. Inhibition of the thioredoxin system in the brain and liver of zebra-seabreams exposed to waterborne methylmercury

    International Nuclear Information System (INIS)

    Branco, Vasco; Canario, Joao; Holmgren, Arne; Carvalho, Cristina

    2011-01-01

    Mercury compounds were recently found to interact in vitro with the thioredoxin system, inhibiting both Thioredoxin (Trx) and Thioredoxin reductase (TrxR). In order to evaluate if Trx and TrxR are affected in vivo by methylmercury (MeHg), we exposed juvenile zebra-seabreams to different concentrations of this toxicant in water for 28 days followed by a 14-day depuration period. Methylmercury accumulated to a larger extent in the kidney and liver of fishes, but decreased significantly during the depuration. During the exposure, MeHg percentage in the liver reached levels above 90% of total mercury (HgT) decreasing to 60% of HgT by the end of the depuration period. In the kidney, MeHg accounted for 50-70% of HgT. In the brain and muscle, mercury accumulated throughout the exposure with all mercury being MeHg. The total mercury kept increasing in these organs during the depuration period. However, in the brain, this increase in HgT was accompanied by a decrease in the MeHg percentage (∼ 10%). In the liver, both Trx and TrxR activities were significantly reduced (TrxR - 40%; Trx - 70%) by the end of the exposure, but recovered to control levels (100%) during the depuration. In the brain, both enzymes where inhibited during the depuration period (TrxR - 75%; Trx - 70%) when some production of inorganic mercury was detected. Activity of glutathione reductase showed increased levels when TrxR activity was low, suggesting complementarity between both systems. These results indicate that in vivo the thioredoxin system is a toxicological target for MeHg with TrxR being particularly affected.

  9. Assessment of gill pathological responses in the tropical fish yellowfin seabream of Persian Gulf under mercury exposure

    Directory of Open Access Journals (Sweden)

    Leila Hassaninezhad

    2014-01-01

    Full Text Available Gill histomorphological alterations were used to assess the effects of chronic exposure to HgCl2 on the yellowfin seabream, Acanthopagrus latus. In this regard, 90 A. latus were exposed to sublethal concentrations of HgCl2 (10, 20, 35 and 50 μg/L for 3 weeks. Treated fish were erratic and showed respiratory distress. The most common morphological abnormalities included: filaments disorganization, increase of mucus secretion, debris and blood plaques on the filaments, losing or shortening of some filaments. The most frequent histopathological changes detected in the gills included extensive lifting of the lamellar epithelium and edema of lamellae with enlarged sub-epithelial spaces, exfoliated epithelium of lamellae, telangiectasia, hypertrophy and hyperplasia of the epithelial cell resulted in partial fusion of the secondary lamellae and a reduction of the water space, club shaping of gill lamellae, blood congestion. Some more severe alternations found in the gill of fish exposed to higher levels of HgCl2 (35 and 50 μg/L included lamellar aneurysm and hemorrhages with rupture of the lamellar epithelium. According to the results of the present study, mercuric chloride could cause major histomorphological changes in the gill of A. latus, decreasing its gas exchange capability. Two mercury concentrations (10 and 20 μg/L used in the present study were in agreement with the concentration of mercury in the water of different parts of Mahshahr creeks (the north of Persian Gulf (3.66 to 15 μg/L. Therefore, based on the results the presence of pathological alteration in A. latus inhibited in the natural environment (Mahshahr creeks seems to be logical.

  10. Geographic, genetic and life-history variability in a sex-changing fish

    Directory of Open Access Journals (Sweden)

    Chiara Benvenuto

    2015-11-01

    Full Text Available Sequential hermaphroditism, commonly referred to as sex change or sex reversal, is a striking phenomenon in mating-system evolution and the most remarkable example of sexual plasticity. Among vertebrates, it is specific to teleosts. Some fish species reproduce initially as females and then change into males (protogynous hermaphrodites or vice versa (protandrous hermaphrodites. The white sea bream, Diplodus sargus, exhibits a high degree of sexual plasticity: populations have been reported to be gonochoristic, protandrous or digynic (with primary females, derived from intersexual juveniles, and secondary females, derived from males. We analysed populations collected from eight different locations across the species distribution range (between the Mediterranean and the North-Eastern Atlantic. These populations are characterized by different degrees of connectivity, spatial demographics and life histories. Using individual-based analyses, we linked the genetic structure of each specimen with environmental heterogeneity, life-history traits and reproductive modes. Our aim is to gather a better understanding of the variation in reproductive life-history strategies in this sexually plastic species. Diplodus sargus is a valuable candidate organism to investigate sequential hermaphroditism and it also has a commercial value. The application of population genetics tools against the background of life-history theory can bring valuable insights for the management of marine resources. The geographical patterns of sex change (and of age- and size-at-sex change linked with population genetics can be pivotal for both theoretical investigations and conservation and management plans in marine areas.

  11. Gilthead seabream (Sparus aurata) response to three music stimuli (Mozart--"Eine Kleine Nachtmusik," Anonymous--"Romanza," Bach--"Violin Concerto No. 1") and white noise under recirculating water conditions.

    Science.gov (United States)

    Papoutsoglou, Sofronios E; Karakatsouli, Nafsika; Psarrou, Anna; Apostolidou, Sofia; Papoutsoglou, Eustratios S; Batzina, Alkisti; Leondaritis, Georgios; Sakellaridis, N

    2015-02-01

    This study presents the results of the response of Sparus aurata to three different musical stimuli, derived from the transmission (4 h per day, 5 days per week) of particular music pieces by Mozart, Romanza and Bach (140 dB(rms) re 1 μPa), compared to the same transmission level of white noise, while the underwater ambient noise in all the experimental tanks was 121 dB(rms) re 1 μPa. Using recirculating sea water facilities, 10 groups, 2 for each treatment, of 20 specimens of 11.2 ± 0.02 g (S.E.), were reared for 94 days, under 150 ± 10 l× 12L-12D, and were fed an artificial diet three times per day. Fish body weight showed significant differences after 55 days, while its maximum level was observed after the 69th day until the end of the experiment, the highest value demonstrated in Mozart (M) groups, followed by those of Romanza (R), Bach (B), control (C) and white noise (WN). SGR (M = B), %WG (M = B) and FCR (all groups fed same % b.w.) were also improved for M group. Brain neurotransmitters results exhibited significant differences in DA-dopamine, (M > B), 5HIAA (C > B), 5HIAA:5HT (WN > R), DOPAC (M > B), DOPAC:DA and (DOPAC + HVA):DA, (C > M), while no significant differences were observed in 5HT, NA, HVA and HVA:DA. No differences were observed in biometric measurements, protease activity, % fatty acids of fillet, visceral fat and liver, while differences were observed regarding carbohydrase activity and the amount (mg/g w.w.) of some fatty acids in liver, fillet and visceral fat. In conclusion, present results confirm those reported for S. aurata, concerning the observed relaxing influence--due to its brain neurotransmitters action--of the transmission of Mozart music (compared to R and B), which resulted in the achievement of maximum growth rate, body weight and improved FCR. This conclusion definitely supports the musical "understanding" and sensitivity of S. aurata to music stimuli as well as suggesting a specific effect of white noise.

  12. The Embeddedness of White Fragility within White Pre-Service Principals' Reflections on White Privilege

    Science.gov (United States)

    Hines, Mack T., III

    2016-01-01

    This study analyzes the prevalence of white fragility within the six white, pre-service principals' online responses to readings about white privilege. Six white, pre-service principals were asked to provide commentary to class readings on the relevance of white privilege to their preparation for future positions as principals. The findings showed…

  13. Alterations of gene expression indicating effects on estrogen signaling and lipid homeostasis in seabream hepatocytes exposed to extracts of seawater sampled from a coastal area of the central Adriatic Sea (Italy).

    Science.gov (United States)

    Cocci, Paolo; Capriotti, Martina; Mosconi, Gilberto; Campanelli, Alessandra; Frapiccini, Emanuela; Marini, Mauro; Caprioli, Giovanni; Sagratini, Gianni; Aretusi, Graziano; Palermo, Francesco Alessandro

    2017-02-01

    Recent evidences suggest that the toxicological effects of endocrine disrupting chemicals (EDCs) involve multiple nuclear receptor-mediated pathways, including estrogen receptor (ER) and peroxisome proliferator-activated receptor (PPAR) signaling systems. Thus, our objective in this study was to detect the summated endocrine effects of EDCs with metabolic activity in coastal waters of the central Adriatic Sea by means of a toxicogenomic approach using seabream hepatocytes. Gene expression patterns were also correlated with seawater levels of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). We found that seawater extracts taken at certain areas induced gene expression profiles of ERα/vitellogenin, PPARα/Stearoyl-CoA desaturase 1A, cytochrome P4501A (CYP1A) and metallothionein. These increased levels of biomarkers responses correlated with spatial distribution of PAHs/PCBs concentrations observed by chemical analysis in the different study areas. Collectively, our data give a snapshot of the presence of complex EDC mixtures that are able to perturb metabolic signaling in coastal marine waters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Narrative Constructions of Whiteness among White Undergraduates

    Science.gov (United States)

    Foste, Zak

    2017-01-01

    This critical narrative inquiry was guided by two overarching research questions. First, this study examined how white undergraduates interpreted and gave meaning to their white racial identities. This line of inquiry sought to understand how participants made sense of their white racial selves, the self in relation to people of color, and the…

  15. In vitro effects of Italian Lavandula multifida L. leaf extracts on gilthead seabream (Sparus aurata) leucocytes and SAF-1 cells.

    Science.gov (United States)

    Fazio, Angela; Cerezuela, Rebeca; Panuccio, Maria Rosaria; Cuesta, Alberto; Esteban, Maria Ángeles

    2017-07-01

    Lavandula multifida is very appreciated by pharmaceutical and cosmetic industries. In Italy is only found in Calabria and Sicily and, at present, urge its valorization due to its high extinction and genetic erosion risks. Possible applications of L. multifida extracts as immunostimulant in fish aquaculture were assayed by using gilthead seabream (Sparus aurata) as a marine fish model, due to its importance in fish aquaculture. The in vitro effects of both aqueous and ethanolic leaf extracts obtained from two Italian populations of L. multifida on head kidney leucocyte activities (viability, phagocytosis, respiratory burst and peroxidase content) were assessed. Furthermore, the possible cytotoxic effects of the extracts on SAF-1 cells and their bactericidal effects on three fish pathogenic bacteria (Vibrio harveyi, Vibrio anguillarum, Aeromonas salmonicida) were also evaluated. All the assays were performed in comparison with leaf extracts obtained from a widely-distributed species as L. angustifolia. Results showed that water and ethanolic leaf extracts obtained from L. multifida enhanced innate immune activities of S. aurata HK leucocytes. Furthermore, SAF-1 cell viability was not affected significantly after being incubated with the extracts. These extracts did not exert any bactericidal activity on the pathogenic bacterial strains tested in the present study. Results obtained in the present work suggested the possibility of use such extracts in in vivo studies in order to corroborate the possibility of their use in aquaculture. Their use could prevent to improve fish defense against pathogenic infections through enhancement of the fish immune status. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Let's Talk about Race, Baby: How a White Professor Teaches White Students about White Privilege and Racism

    Science.gov (United States)

    Heinze, Peter

    2008-01-01

    There are a variety of methods by which the themes of White privilege and racism can be presented to White students. By using the concept of racial identity a continuum of racism can be considered. Furthermore, addressing White privilege and racism in the context of a multicultural psychology course allows White students to have a greater…

  17. Acidic digestion in a teleost: postprandial and circadian pattern of gastric pH, pepsin activity, and pepsinogen and proton pump mRNAs expression.

    Science.gov (United States)

    Yúfera, Manuel; Moyano, Francisco J; Astola, Antonio; Pousão-Ferreira, Pedro; Martínez-Rodríguez, Gonzalo

    2012-01-01

    Two different modes for regulation of stomach acid secretion have been described in vertebrates. Some species exhibit a continuous acid secretion maintaining a low gastric pH during fasting. Others, as some teleosts, maintain a neutral gastric pH during fasting while the hydrochloric acid is released only after the ingestion of a meal. Those different patterns seem to be closely related to specific feeding habits. However, our recent observations suggest that this acidification pattern could be modified by changes in daily feeding frequency and time schedule. The aim of this study was to advance in understanding the regulation mechanisms of stomach digestion and pattern of acid secretion in teleost fish. We have examined the postprandial pattern of gastric pH, pepsin activity, and mRNA expression for pepsinogen and proton pump in white seabream juveniles maintained under a light/dark 12/12 hours cycle and receiving only one morning meal. The pepsin activity was analyzed according to the standard protocol buffering at pH 2 and using the actual pH measured in the stomach. The results show how the enzyme precursor is permanently available while the hydrochloric acid, which activates the zymogen fraction, is secreted just after the ingestion of food. Results also reveal that analytical protocol at pH 2 notably overestimates true pepsin activity in fish stomach. The expression of the mRNA encoding pepsinogen and proton pump exhibited almost parallel patterns, with notable increases during the darkness period and sharp decreases just before the morning meal. These results indicate that white seabream uses the resting hours for recovering the mRNA stock that will be quickly used during the feeding process. Our data clearly shows that both daily illumination pattern and feeding time are involved at different level in the regulation of the secretion of digestive juices.

  18. Acidic digestion in a teleost: postprandial and circadian pattern of gastric pH, pepsin activity, and pepsinogen and proton pump mRNAs expression.

    Directory of Open Access Journals (Sweden)

    Manuel Yúfera

    Full Text Available Two different modes for regulation of stomach acid secretion have been described in vertebrates. Some species exhibit a continuous acid secretion maintaining a low gastric pH during fasting. Others, as some teleosts, maintain a neutral gastric pH during fasting while the hydrochloric acid is released only after the ingestion of a meal. Those different patterns seem to be closely related to specific feeding habits. However, our recent observations suggest that this acidification pattern could be modified by changes in daily feeding frequency and time schedule. The aim of this study was to advance in understanding the regulation mechanisms of stomach digestion and pattern of acid secretion in teleost fish. We have examined the postprandial pattern of gastric pH, pepsin activity, and mRNA expression for pepsinogen and proton pump in white seabream juveniles maintained under a light/dark 12/12 hours cycle and receiving only one morning meal. The pepsin activity was analyzed according to the standard protocol buffering at pH 2 and using the actual pH measured in the stomach. The results show how the enzyme precursor is permanently available while the hydrochloric acid, which activates the zymogen fraction, is secreted just after the ingestion of food. Results also reveal that analytical protocol at pH 2 notably overestimates true pepsin activity in fish stomach. The expression of the mRNA encoding pepsinogen and proton pump exhibited almost parallel patterns, with notable increases during the darkness period and sharp decreases just before the morning meal. These results indicate that white seabream uses the resting hours for recovering the mRNA stock that will be quickly used during the feeding process. Our data clearly shows that both daily illumination pattern and feeding time are involved at different level in the regulation of the secretion of digestive juices.

  19. White Ring; White ring

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, H.; Yuzawa, H. [Nikken Sekkei Ltd., Osaka (Japan)

    1998-01-05

    White Ring is a citizen`s gymnasium used for figure skating and short track speed skating games of 18th Winter Olympic Games in 1998. White Ring is composed of a main-arena and a sub-arena. For the main-arena with an area 41mtimes66m, an ice link can be made by disengaging the potable floor and by flowing brine in the bridged polystyrene pipes embedded in the concrete floor. Due to the fortunate groundwater in this site, well water is used for the outside air treatment energy in 63% during heating and in 35% during cooling. Ammonia is used as a cooling medium for refrigerating facility. For the heating of audience area in the large space, heat load from the outside is reduced by enhancing the heat insulation performance of the roof of arena. The audience seats are locally heated using heaters. For the White Ring, high quality environment is realized for games through various functions of the large-scale roof of the large space. Success of the big event was expected. 15 figs., 4 tabs.

  20. White Dwarf Stars

    OpenAIRE

    Kepler, S. O.; Romero, Alejandra Daniela; Pelisoli, Ingrid; Ourique, Gustavo

    2017-01-01

    White dwarf stars are the final stage of most stars, born single or in multiple systems. We discuss the identification, magnetic fields, and mass distribution for white dwarfs detected from spectra obtained by the Sloan Digital Sky Survey up to Data Release 13 in 2016, which lead to the increase in the number of spectroscopically identified white dwarf stars from 5000 to 39000. This number includes only white dwarf stars with log g >= 6.5 stars, i.e., excluding the Extremely Low Mass white dw...

  1. The effects of whiteness on the health of whites in the USA.

    Science.gov (United States)

    Malat, Jennifer; Mayorga-Gallo, Sarah; Williams, David R

    2018-02-01

    Whites in the USA are the dominant racial group, with greater than average access to most material and social rewards. Yet, while whites have better outcomes than other racial groups on some health indicators, whites paradoxically compare poorly on other measures. Further, whites in the USA also rank poorly in international health comparisons. In this paper, we present a framework that combines the concept of whiteness-a system that socially, economically, and ideologically benefits European descendants and disadvantages people in other groups-with research from a variety of fields in order to comprehensively model the social factors that influence whites' health. The framework we present describes how whiteness and capitalism in the USA shape societal conditions, individual social characteristics and experiences, and psychosocial responses to circumstances to influence health outcomes. We detail specific examples of how social policies supported by whiteness, the narratives of whiteness, and the privileges of whiteness may positively and negatively affect whites' health. In doing so, we suggest several areas for future research that can expand our understanding of how social factors affect health and can contribute to the patterns and paradoxes of whites' health. By expanding research to include theoretically-grounded analyses of the dominant group's health, we can achieve a more complete picture of how systems of racial inequity affect health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Otolith reading and multi-model inference for improved estimation of age and growth in the gilthead seabream Sparus aurata (L.)

    Science.gov (United States)

    Mercier, Lény; Panfili, Jacques; Paillon, Christelle; N'diaye, Awa; Mouillot, David; Darnaude, Audrey M.

    2011-05-01

    Accurate knowledge of fish age and growth is crucial for species conservation and management of exploited marine stocks. In exploited species, age estimation based on otolith reading is routinely used for building growth curves that are used to implement fishery management models. However, the universal fit of the von Bertalanffy growth function (VBGF) on data from commercial landings can lead to uncertainty in growth parameter inference, preventing accurate comparison of growth-based history traits between fish populations. In the present paper, we used a comprehensive annual sample of wild gilthead seabream ( Sparus aurata L.) in the Gulf of Lions (France, NW Mediterranean) to test a methodology improving growth modelling for exploited fish populations. After validating the timing for otolith annual increment formation for all life stages, a comprehensive set of growth models (including VBGF) were fitted to the obtained age-length data, used as a whole or sub-divided between group 0 individuals and those coming from commercial landings (ages 1-6). Comparisons in growth model accuracy based on Akaike Information Criterion allowed assessment of the best model for each dataset and, when no model correctly fitted the data, a multi-model inference (MMI) based on model averaging was carried out. The results provided evidence that growth parameters inferred with VBGF must be used with high caution. Hence, VBGF turned to be among the less accurate for growth prediction irrespective of the dataset and its fit to the whole population, the juvenile or the adult datasets provided different growth parameters. The best models for growth prediction were the Tanaka model, for group 0 juveniles, and the MMI, for the older fish, confirming that growth differs substantially between juveniles and adults. All asymptotic models failed to correctly describe the growth of adult S. aurata, probably because of the poor representation of old individuals in the dataset. Multi

  3. The influences of fish infusion broth on the biogenic amines formation by lactic acid bacteria

    Directory of Open Access Journals (Sweden)

    Esmeray Küley

    2013-01-01

    Full Text Available The influences of fish infusion decarboxylase broth (IDB on biogenic amines (BA formation by lactic acid bacteria (LAB were investigated. BA productions by single LAB strains were tested in five different fish (anchovy, mackerel, white shark, sardine and gilthead seabream IDB. The result of the study showed that significant differences in ammonia (AMN and BA production were observed among the LAB strains in fish IDB (p < 0.05. The highest AMN and TMA production by LAB strains were observed for white shark IDB. The all tested bacteria had decarboxylation activity in fish IDB. The uppermost accumulated amines by LAB strains were tyramine (TYM, dopamine, serotonin and spermidine. The maximum histamine production was observed in sardine (101.69 mg/L and mackerel (100.84 mg/L IDB by Leuconostoc mesenteroides subsp. cremoris and Pediococcus acidophilus, respectively. Lactobacillus delbrueckii subsp. lactis and Pediococcus acidophilus had a high TYM producing capability (2943 mg/L and 1157 mg/L in sardine IDB.

  4. Racializing white drag.

    Science.gov (United States)

    Rhyne, Ragan

    2004-01-01

    While drag is primarily understood as a performance of gender, other performative categories such as race, class, and sexuality create drag meaning as well. Though other categories of identification are increasingly understood as essential elements of drag by performers of color, whiteness remains an unmarked category in the scholarship on drag performances by white queens. In this paper, I argue that drag by white queens must be understood as a performance of race as well as gender and that codes of gender excess are specifically constructed through the framework of these other axes of identity. This essay asks whether white performance by white queens necessarily reinscribes white supremacy through the performance of an unmarked white femininity, or might drag performance complicate (though not necessarily subvert) categories of race as well as gender? In this essay, I will suggest that camp drag performances, through the deployment of class as a crucial category of performative femininity, might indeed be a key site through which whiteness is denaturalized and its power challenged. Specifically, I will read on camp as a politicized mode of race, class and gender performance, focusing on the intersections of these categories of identity in the drag performance of Divine.

  5. Are retailers' preferences for seafood attributes predictive for consumers wants?

    DEFF Research Database (Denmark)

    Fernández-Polancoa, José; Mueller Loose, Simone; Luna, Ladislao

    2013-01-01

    Aquaculture production has grown considerably in the southern countries of Europe during the last two decades. This increase in supply has not been matched by an equivalent rise in consumer demand, resulting in price decay. For farmed seabream (Sparus aurata) this paper examines which attributes...... choice and to test for differences in attribute preferences between retailers and consumers. Results indicate that both consumers and retailers agree in their marginal willingness to pay for wild over farmed seabream. However, they differ in the extent to which the disutility from farmed production can...... be offset by the declaration of domestic origin, sustainability certifications, and presence of health benefits or safety claims. Results suggest an asymmetry between retailer and consumer preferences that might explain why seabream differentiated by claims still struggles to find the desired retail...

  6. Fifty shades of white: how white feather brightness differs among species

    Science.gov (United States)

    Igic, Branislav; D'Alba, Liliana; Shawkey, Matthew D.

    2018-04-01

    White colouration is a common and important component of animal visual signalling and camouflage, but how and why it varies across species is poorly understood. White is produced by wavelength-independent and diffuse scattering of light by the internal structures of materials, where the degree of brightness is related to the amount of light scattered. Here, we investigated the morphological basis of brightness differences among unpigmented pennaceous regions of white body feathers across 61 bird species. Using phylogenetically controlled comparisons of reflectance and morphometric measurements, we show that brighter white feathers had larger and internally more complex barbs than duller white feathers. Higher brightness was also associated with more closely packed barbs and barbules, thicker and longer barbules, and rounder and less hollow barbs. Larger species tended to have brighter white feathers than smaller species because they had thicker and more complex barbs, but aquatic species were not significantly brighter than terrestrial species. As similar light scattering principals affect the brightness of chromatic signals, not just white colours, these findings help broaden our general understanding of the mechanisms that affect plumage brightness. Future studies should examine how feather layering on a bird's body contributes to differences between brightness of white plumage patches within and across species.

  7. Erick A. White | NREL

    Science.gov (United States)

    Engineering, Colorado School of Mines, 2011 B.S., Chemical Engineering, University of Colorado at Boulder Research Assistant, Colorado School of Mines, Department of Chemical Engineering, 2006-2011 Field Team Erick A. White Photo of Erick A. White Erick White Chemical Reaction Engineer Erick.White@nrel.gov

  8. Keeping Minorities Happy: Hierarchy Maintenance and Whites' Decreased Support for Highly Identified White Politicians.

    Science.gov (United States)

    Jun, Sora; Lowery, Brian S; Guillory, Lucia

    2017-12-01

    We test the hypothesis that, to avoid provoking minorities, Whites will withhold their support for White political candidates who are highly identified with their race. In Study 1, we found that White Republicans were less supportive of White candidates the higher the perceived White identity of the candidate due to beliefs that such candidates would provoke racial minorities. In Study 2, we replicated this effect with a manipulation of candidates' White identity. Study 3 found that Whites reported less support for high-identity candidates when they were led to believe that the hierarchy was unstable rather than stable. Consistent with our hypothesis that those who have the most to lose are most likely to avoid provoking minorities, in Study 4, we found that Whites with high subjective socioeconomic status (SES) varied their support for provocative White candidates as a function of hierarchy stability, whereas those with low subjective SES did not.

  9. White Privilege? The Intersection of Hip-Hop and Whiteness as a Catalyst for Cross-Racial Interaction among White Males

    Science.gov (United States)

    Sulé, Venice Thandi

    2015-01-01

    Given the prevalence of racial segregation in the U.S., college is an opportunity to prepare students for diversity through cross-racial interaction. Hip-hop, a culture steeped in black and Latino experiences, has significant white supporters. Through diversity and critical whiteness frameworks, this research considers how white hip-hop collegians…

  10. Inheritance of skeletal deformities in gilthead seabream (Sparus aurata) - lack of operculum, lordosis, vertebral fusion and LSK complex.

    Science.gov (United States)

    Negrín-Báez, D; Navarro, A; Lee-Montero, I; Soula, M; Afonso, J M; Zamorano, M J

    2015-01-01

    Morphological abnormalities in farmed gilthead seabream (Sparus aurata) are a major problem as it entails significant economic losses. In this study, 3 large scale experiments under different conditions of spawning, offspring handling and breeders phenotype were performed to analyze the inheritance of 4 types of deformities in this species: lack of operculum, lordosis, vertebral fusion, which are 3 of the most important skeletal deformities, and LSK, which is a consecutive repetition of lordosis/scoliosis/kyphosis. In Exp. [1] (mass spawning and fingerling sorting), 900 fish were analyzed at 509 d post-hatching: 846 fish that had been on-grown in a farm and 54 LSK-deformed fish that had been reared separately after being selected during the fingerling sorting process. A total of 89 families were represented. A statistically significant association between 5 of these families (from 6 breeders) and LSK-deformed fish was found. In Exp. [2] (mass spawning and no fingerling sorting), 810 fish were analyzed at 2 ages: 179 and 689 d post-hatching. Significant relationships between 2 of the breeders and 2 of the families with the lack of operculum prevalence of their descendants were found at 689 d but not at 179 d. Heritabilities: 0.09 ± 0.09 at 179 d and 0.17 ± 0.08 at 689 d. Column deformities prevalence was low and no association with family was observed. Family relationships were determined by microsatellites multiplex PCR in both experiments. In Exp. [3] (designed mating), sires suffering from lordosis or lack of operculum or vertebral fusion deformities were mated with non-deformed dams and a mass-spawning mating was considered as a control. After analyzing 11,503 offspring at 159 d post-hatching, a significant relationship between each deformity prevalence and the mating of breeders suffering from the same deformity was observed. In addition, a significant prevalence of lack of operculum in offspring from lordotic matings was observed. Heritabilities ranged from

  11. Red flag on the white reporter: a versatile insulator abuts the white gene in Drosophila and is omnipresent in mini-white constructs

    OpenAIRE

    Chetverina, Darya; Savitskaya, Ekaterina; Maksimenko, Oksana; Melnikova, Larisa; Zaytseva, Olga; Parshikov, Alexander; Galkin, Alexander V.; Georgiev, Pavel

    2007-01-01

    Much of the research on insulators in Drosophila has been done with transgenic constructs using the white gene (mini-white) as reporter. Hereby we report that the sequence between the white and CG32795 genes in Drosophila melanogaster contains an insulator of a novel kind. Its functional core is within a 368 bp segment almost contiguous to the white 3′UTR, hence we name it as Wari (white-abutting resident insulator). Though Wari contains no binding sites for known insulator proteins and does ...

  12. Molecular genetics of coat colour variations in White Galloway and White Park cattle.

    Science.gov (United States)

    Brenig, B; Beck, J; Floren, C; Bornemann-Kolatzki, K; Wiedemann, I; Hennecke, S; Swalve, H; Schütz, E

    2013-08-01

    White Galloway cattle exhibit three different white coat colour phenotypes, that is, well marked, strongly marked and mismarked. However, mating of individuals with the preferred well or strongly marked phenotype also results in offspring with the undesired mismarked and/or even fully black coat colour. To elucidate the genetic background of the coat colour variations in White Galloway cattle, we analysed four coat colour relevant genes: mast/stem cell growth factor receptor (KIT), KIT ligand (KITLG), melanocortin 1 receptor (MC1R) and tyrosinase (TYR). Here, we show that the coat colour variations in White Galloway cattle and White Park cattle are caused by a KIT gene (chromosome 6) duplication and aberrant insertion on chromosome 29 (Cs29 ) as recently described for colour-sided Belgian Blue. Homozygous (Cs29 /Cs29 ) White Galloway cattle and White Park cattle exhibit the mismarked phenotype, whereas heterozygous (Cs29 /wt29 ) individuals are either well or strongly marked. In contrast, fully black individuals are characterised by the wild-type chromosome 29. As known for other cattle breeds, mutations in the MC1R gene determine the red colouring. Our data suggest that the white coat colour variations in White Galloway cattle and White Park cattle are caused by a dose-dependent effect based on the ploidy of aberrant insertions and inheritance of the KIT gene on chromosome 29. © 2013 The Authors, Animal Genetics © 2013 Stichting International Foundation for Animal Genetics.

  13. White Rock

    Science.gov (United States)

    2002-01-01

    (Released 19 April 2002) The Science 'White Rock' is the unofficial name for this unusual landform which was first observed during the Mariner 9 mission in the early 1970's. As later analysis of additional data sets would show, White Rock is neither white nor dense rock. Its apparent brightness arises from the fact that the material surrounding it is so dark. Images from the Mars Global Surveyor MOC camera revealed dark sand dunes surrounding White Rock and on the floor of the troughs within it. Some of these dunes are just apparent in the THEMIS image. Although there was speculation that the material composing White Rock could be salts from an ancient dry lakebed, spectral data from the MGS TES instrument did not support this claim. Instead, the White Rock deposit may be the erosional remnant of a previously more continuous occurrence of air fall sediments, either volcanic ash or windblown dust. The THEMIS image offers new evidence for the idea that the original deposit covered a larger area. Approximately 10 kilometers to the southeast of the main deposit are some tiny knobs of similarly bright material preserved on the floor of a small crater. Given that the eolian erosion of the main White Rock deposit has produced isolated knobs at its edges, it is reasonable to suspect that the more distant outliers are the remnants of a once continuous deposit that stretched at least to this location. The fact that so little remains of the larger deposit suggests that the material is very easily eroded and simply blows away. The Story Fingers of hard, white rock seem to jut out like icy daggers across a moody Martian surface, but appearances can be deceiving. These bright, jagged features are neither white, nor icy, nor even hard and rocky! So what are they, and why are they so different from the surrounding terrain? Scientists know that you can't always trust what your eyes see alone. You have to use other kinds of science instruments to measure things that our eyes can

  14. Diseases of white matter

    International Nuclear Information System (INIS)

    Holland, B.A.

    1987-01-01

    The diagnosis of white matter abnormalities was revolutionized by the advent of computed tomography (CT), which provided a noninvasive method of detection and assessment of progression of a variety of white matter processes. However, the inadequacies of CT were recognized early, including its relative insensitivity to small foci of abnormal myelin in the brain when correlated with autopsy findings and its inability to image directly white matter diseases of the spinal cord. Magnetic resonance imaging (MRI), on the other hand, sensitive to the slight difference in tissue composition of normal gray and white matter and to subtle increase in water content associated with myelin disorders, is uniquely suited for the examination of white matter pathology. Its clinical applications include the evaluation of the normal process of myelination in childhood and the various white matter diseases, including disorders of demyelination and dysmyelination

  15. Low White Blood Cell Count

    Science.gov (United States)

    Symptoms Low white blood cell count By Mayo Clinic Staff A low white blood cell count (leukopenia) is a decrease ... of white blood cell (neutrophil). The definition of low white blood cell count varies from one medical ...

  16. Making Whites from the Dark Side: Teaching Whiteness Studies at San Francisco State University

    Science.gov (United States)

    Sueyoshi, Amy

    2013-01-01

    While whiteness studies at most institutions aims to expose the persistence of white supremacy to a disbelieving audience, whiteness studies within the College of Ethnic Studies (COES) at San Francisco State University (SFSU) begins with the assumption that racism still exists. The course then traces how whiteness is constructed and fortified to…

  17. Silvicultural guide for northern white-cedar (eastern white cedar)

    Science.gov (United States)

    Emmanuelle Boulfroy; Eric Forget; Philip V. Hofmeyer; Laura S. Kenefic; Catherine Larouche; Guy Lessard; Jean-Martin Lussier; Fred Pinto; Jean-Claude Ruel; Aaron. Weiskittel

    2012-01-01

    Northern white-cedar (eastern white cedar; Thuja occidentalis L.) is an important tree species in the northeastern United States and adjacent Canada, occurring both in pure stands and as a minor species in mixed stands of hardwoods or other softwoods. Yet practitioners have little and often contradictory information about cedar ecology and...

  18. White public regard: associations among eating disorder symptomatology, guilt, and White guilt in young adult women.

    Science.gov (United States)

    Lydecker, Janet A; Hubbard, Rebecca R; Tully, Carrie B; Utsey, Shawn O; Mazzeo, Suzanne E

    2014-01-01

    As a novel investigation of the role of White racial identity, the current study explored the link between White guilt and disordered eating. Young adult women (N=375), 200 of whom self-identified as White. Measures assessed disordered eating, trait guilt, White guilt, and affect. White guilt is interrelated with disordered eating, particularly bulimic symptomatology. Distress tolerance and tendency to experience negative affect moderated the relation between White guilt and several disordered eating variables. Exploration of White guilt in clinical and research settings can inform understanding and treatment of disordered eating. © 2013.

  19. Think leader, think White? Capturing and weakening an implicit pro-White leadership bias.

    Science.gov (United States)

    Gündemir, Seval; Homan, Astrid C; de Dreu, Carsten K W; van Vugt, Mark

    2014-01-01

    Across four studies, we found evidence for an implicit pro-White leadership bias that helps explain the underrepresentation of ethnic minorities in leadership positions. Both White-majority and ethnic minority participants reacted significantly faster when ethnically White names and leadership roles (e.g., manager; Study 1) or leadership traits (e.g., decisiveness; Study 2 & 3) were paired in an Implicit Association Test (IAT) rather than when ethnic minority names and leadership traits were paired. Moreover, the implicit pro-White leadership bias showed discriminant validity with the conventional implicit bias measures (Study 3). Importantly, results showed that the pro-White leadership bias can be weakened when situational cues increase the salience of a dual identity (Study 4). This, in turn, can diminish the explicit pro-White bias in promotion related decision making processes (Study 4). This research offers a new tool to measure the implicit psychological processes underlying the underrepresentation of ethnic minorities in leadership positions and proposes interventions to weaken such biases.

  20. Think Leader, Think White? Capturing and Weakening an Implicit Pro-White Leadership Bias

    Science.gov (United States)

    Gündemir, Seval; Homan, Astrid C.; de Dreu, Carsten K. W.; van Vugt, Mark

    2014-01-01

    Across four studies, we found evidence for an implicit pro-White leadership bias that helps explain the underrepresentation of ethnic minorities in leadership positions. Both White-majority and ethnic minority participants reacted significantly faster when ethnically White names and leadership roles (e.g., manager; Study 1) or leadership traits (e.g., decisiveness; Study 2 & 3) were paired in an Implicit Association Test (IAT) rather than when ethnic minority names and leadership traits were paired. Moreover, the implicit pro-White leadership bias showed discriminant validity with the conventional implicit bias measures (Study 3). Importantly, results showed that the pro-White leadership bias can be weakened when situational cues increase the salience of a dual identity (Study 4). This, in turn, can diminish the explicit pro-White bias in promotion related decision making processes (Study 4). This research offers a new tool to measure the implicit psychological processes underlying the underrepresentation of ethnic minorities in leadership positions and proposes interventions to weaken such biases. PMID:24416181

  1. Think leader, think White? Capturing and weakening an implicit pro-White leadership bias.

    Directory of Open Access Journals (Sweden)

    Seval Gündemir

    Full Text Available Across four studies, we found evidence for an implicit pro-White leadership bias that helps explain the underrepresentation of ethnic minorities in leadership positions. Both White-majority and ethnic minority participants reacted significantly faster when ethnically White names and leadership roles (e.g., manager; Study 1 or leadership traits (e.g., decisiveness; Study 2 & 3 were paired in an Implicit Association Test (IAT rather than when ethnic minority names and leadership traits were paired. Moreover, the implicit pro-White leadership bias showed discriminant validity with the conventional implicit bias measures (Study 3. Importantly, results showed that the pro-White leadership bias can be weakened when situational cues increase the salience of a dual identity (Study 4. This, in turn, can diminish the explicit pro-White bias in promotion related decision making processes (Study 4. This research offers a new tool to measure the implicit psychological processes underlying the underrepresentation of ethnic minorities in leadership positions and proposes interventions to weaken such biases.

  2. On Describing Human White Matter Anatomy: The White Matter Query Language

    OpenAIRE

    Wassermann, Demian; Makris, Nikos; Rathi, Yogesh; Shenton, Martha; Kikinis, Ron; Kubicki, Marek; Westin, Carl-Fredrik

    2013-01-01

    The main contribution of this work is the careful syntactical definition of major white matter tracts in the human brain based on a neuroanatomist’s expert knowledge. We present a technique to formally describe white matter tracts and to automatically extract them from diffusion MRI data. The framework is based on a novel query language with a near-to-English textual syntax. This query language allows us to construct a dictionary of anatomical definitions describing white matter tracts. The d...

  3. White Faculty Transforming Whiteness in the Classroom through Pedagogical Practice

    Science.gov (United States)

    Charbeneau, Jessica

    2015-01-01

    The primary objective of this qualitative study is to present a conceptual framework of pedagogical practices reported by white faculty that serve to challenge the hegemony of whiteness in the university classroom. These transformative teaching practices surfaced through a review of racialized pedagogies discussed in the literature and in…

  4. Stark Broadening and White Dwarfs

    Directory of Open Access Journals (Sweden)

    Dimitrijević Milan S.

    2011-12-01

    Full Text Available White dwarf and pre-white dwarfs are the best types of stars for the application of Stark broadening research results in astrophysics, since in the atmospheres of these stars physical conditions are very favorable for this line broadening mechanism - in hot hydrogen-deficient white dwarfs and pre-white dwarfs Teff = 75 000–180 000 K and log g = 5.5–8 [cgs]. Even for much cooler DA and DB white dwarfs with the typical effective temperatures 10 000-20 000 K, Stark broadening is usually the dominant broadening mechanism. In this review, Stark broadening in white dwarf spectra is considered, and the attention is drawn to the STARK-B database (http://stark-b.obspm.fr/, containing the parameters needed for analysis and synthesis of white dwarf spectra, as well as for the collective efforts to develop the Virtual Atomic and Molecular Data Center.

  5. Nesting success of White Terns and White-tailed Tropicbirds on ...

    African Journals Online (AJOL)

    This study investigates the breeding success of two tropical seabirds that exploit dissimilar nesting habitats on Cousine Island in the Seychelles archipelago, the White Tern Gygis alba and the White-tailed Tropicbird Phaethon lepturus, which nest in trees and in crevices on the ground, respectively. Both species have a ...

  6. Perinatal outcomes among Asian-white interracial couples.

    Science.gov (United States)

    Nystrom, Michael J; Caughey, Aaron B; Lyell, Deirdre J; Druzin, Maurice L; El-Sayed, Yasser Y

    2008-10-01

    To investigate whether perinatal outcomes among interracial Asian-white couples are different than among Asian-Asian and white-white couples. This was a retrospective study of Asian, white, and Asian-white couples delivered at the Lucile Packard Children's Hospital from 2000-2005. Asian-white couples were subdivided into white-mother/Asian-father or Asian-mother/white-father. Perinatal outcomes included gestational diabetes, hypertensive disorders of pregnancy, preterm delivery, birth weight >4000 g and interracial Asian-white couples.

  7. Black and white holes

    International Nuclear Information System (INIS)

    Zeldovich, Ya.; Novikov, I.; Starobinskij, A.

    1978-01-01

    The theory is explained of the origination of white holes as a dual phenomenon with regard to the formation of black holes. Theoretically it is possible to derive the white hole by changing the sign of time in solving the general theory of relativity equation implying the black hole. The white hole represents the amount of particles formed in the vicinity of a singularity. For a distant observer, matter composed of these particles expands and the outer boundaries of this matter approach from the inside the gravitational radius Rsub(r). At t>>Rsub(r)/c all radiation or expulsion of matter terminates. For the outside observer the white hole exists for an unlimited length of time. In fact, however, it acquires the properties of a black hole and all processes in it cease. The qualitative difference between a white hole and a black hole is in that a white hole is formed as the result of an inner quantum explosion from the singularity to the gravitational radius and not as the result of a gravitational collapse, i.e., the shrinkage of diluted matter towards the gravitational radius. (J.B.)

  8. Black and white holes

    Energy Technology Data Exchange (ETDEWEB)

    Zeldovich, Ya; Novikov, I; Starobinskii, A

    1978-07-01

    The theory is explained of the origination of white holes as a dual phenomenon with regard to the formation of black holes. Theoretically it is possible to derive the white hole by changing the sign of time in solving the general theory of relativity equation implying the black hole. The white hole represents the amount of particles formed in the vicinity of a singularity. For a distant observer, matter composed of these particles expands and the outer boundaries of this matter approach from the inside the gravitational radius R/sub r/. At t>>R/sub r//c all radiation or expulsion of matter terminates. For the outside observer the white hole exists for an unlimited length of time. In fact, however, it acquires the properties of a black hole and all processes in it cease. The qualitative difference between a white hole and a black hole is in that a white hole is formed as the result of an inner quantum explosion from the singularity to the gravitational radius and not as the result of a gravitational collapse, i.e., the shrinkage of diluted matter towards the gravitational radius.

  9. Classification of intestinal lymphangiectasia with protein-losing enteropathy: white villi type and non-white villi type.

    Science.gov (United States)

    Ohmiya, Naoki; Nakamura, Masanao; Yamamura, Takeshi; Yamada, Koji; Nagura, Asuka; Yoshimura, Toru; Hirooka, Yoshiki; Hirata, Ichiro; Goto, Hidemi

    2014-01-01

    We classified intestinal lymphangiectasia (IL) into two categories, the white and non-white villi types, and evaluated their clinical characteristics and therapeutic responses. Of the 988 patients who underwent double-balloon enteroscopy, 14 consecutive patients (7 men and 7 women, median age at onset 34 years) were enrolled with immunohistochemically confirmed IL with protein-losing enteropathy. Enteroscopically the white villi type (n = 8) showed white plaques and white-tipped villi were scattered in the small bowel, while non-white villi type (n = 6) showed that apparently normal but under more detailed observation, low and round villi with a normal color were diffused. The serum albumin levels and fecal α1-antitrypsin clearance before treatment were significantly worse in the non-white villi type (p = 0.017 and 0.039, respectively), whereas the serum immunoglobulin A and M levels were significantly lower in the white villi type (p = 0.010 and 0.046, respectively). At gastroscopy, a non-cirrhotic snakeskin appearance was significantly observed in the non-white villi type (p = 0.015). The corticosteroid response was better in the non-white villi type (p = 0.015). Two distinct subgroups were found in IL. This classification was useful in pathophysiological clustering and in predicting the therapeutic response. © 2014 S. Karger AG, Basel.

  10. Beyond Black and White: How White, Male, College Students See Their Asian American Peers

    Science.gov (United States)

    Cabrera, Nolan L.

    2014-01-01

    This research is a cross-site analysis of how white, male, college students see their Asian American peers. Semi-structured interviews with 43 white males were conducted at two universities that differed substantially in their representation of Asian American students. The interviews were theoretically framed by Critical Whiteness Studies and Bobo…

  11. THE LINK BETWEEN PLANETARY SYSTEMS, DUSTY WHITE DWARFS, AND METAL-POLLUTED WHITE DWARFS

    International Nuclear Information System (INIS)

    Debes, John H.; Walsh, Kevin J.; Stark, Christopher

    2012-01-01

    It has long been suspected that metal-polluted white dwarfs (types DAZ, DBZ, and DZ) and white dwarfs with dusty disks possess planetary systems, but a specific physical mechanism by which planetesimals are perturbed close to a white dwarf has not yet been fully posited. In this paper, we demonstrate that mass loss from a central star during post-main-sequence evolution can sweep planetesimals into interior mean motion resonances with a single giant planet. These planetesimals are slowly removed through chaotic excursions of eccentricity that in time create radial orbits capable of tidally disrupting the planetesimal. Numerical N-body simulations of the solar system show that a sufficient number of planetesimals are perturbed to explain white dwarfs with both dust and metal pollution, provided other white dwarfs have more massive relic asteroid belts. Our scenario requires only one Jupiter-sized planet and a sufficient number of asteroids near its 2:1 interior mean motion resonance. Finally, we show that once a planetesimal is perturbed into a tidal crossing orbit, it will become disrupted after the first pass of the white dwarf, where a highly eccentric stream of debris forms the main reservoir for dust-producing collisions. These simulations, in concert with observations of white dwarfs, place interesting limits on the frequency of planetary systems around main-sequence stars, the frequency of planetesimal belts, and the probability that dust may obscure future terrestrial planet finding missions.

  12. Creating White Australia

    DEFF Research Database (Denmark)

    McLisky, Claire Louise; Carey, Jane

    Vedtagelsen af White Australien som regeringens politik i 1901 viser, at hvidheden var afgørende for den måde, hvorpå den nye nation i Australien blev konstitueret. Og alligevel har historikere i vid udstrækning overset hvidhed i deres studier af Australiens race fortid. 'Creating White Australia...

  13. Dietary DHA/EPA ratio affected tissue fatty acid profiles, antioxidant capacity, hematological characteristics and expression of lipid-related genes but not growth in juvenile black seabream (Acanthopagrus schlegelii).

    Science.gov (United States)

    Jin, Min; Monroig, Óscar; Lu, You; Yuan, Ye; Li, Yi; Ding, Liyun; Tocher, Douglas R; Zhou, Qicun

    2017-01-01

    An 8-week feeding trial was conducted to investigate the effects of dietary docosahexaenoic to eicosapentaenoic acid ratio (DHA/EPA) on growth performance, fatty acid profiles, antioxidant capacity, hematological characteristics and expression of some lipid metabolism related genes of juvenile black seabream (Acanthopagrus schlegelii) of initial weight 9.47 ± 0.03 g. Five isonitrogenous and isolipidic diets (45% crude protein and 14% crude lipid) were formulated to contain graded DHA/EPA ratios of 0.65, 1.16, 1.60, 2.03 and 2.67. There were no differences in growth performance and feed utilization among treatments. Fish fed higher DHA/EPA ratios had higher malondialdehyde (MDA) contents in serum than lower ratios. Serum triacylglycerol (TAG) content was significantly higher in fish fed the lowest DHA/EPA ratio. Tissue fatty acid profiles reflected the diets despite down-regulation of LC-PUFA biosynthesis genes, fatty acyl desaturase 2 (fads2) and elongase of very long-chain fatty acids 5 (elovl5), by high DHA/EPA ratios. Expression of acetyl-CoA carboxylase alpha (accα) and carnitine palmitoyl transferase 1A (cpt1a) were up-regulated by high DHA/EPA ratio, whereas sterol regulatory element-binding protein-1 (srebp-1) and hormone-sensitive lipase (hsl) were down-regulated. Fatty acid synthase (fas), 6-phosphogluconate dehydrogenase (6pgd) and peroxisome proliferator-activated receptor alpha (pparα) showed highest expression in fish fed intermediate (1.16) DHA/EPA ratio. Overall, this study indicated that dietary DHA/EPA ratio affected fatty acid profiles and significantly influenced lipid metabolism including LC-PUFA biosynthesis and other anabolic and catabolic pathways, and also had impacts on antioxidant capacity and hematological characteristics.

  14. White Teachers/White Schools: Oral Histories from the Struggle against Apartheid.

    Science.gov (United States)

    Wieder, Alan

    2003-01-01

    Presents the oral histories of two white teachers who taught in white South African schools during apartheid. Both combined pedagogy and politics in their lives as teachers and joined other teachers in the struggle against apartheid. Describes the oral history project, apartheid and education, and oral history methodology. Both teachers spent…

  15. Subliminal exposure to faces and racial attitudes : Exposure to whites makes whites like blacks less

    NARCIS (Netherlands)

    Smith, P.K.; Dijksterhuis, A.; Chaiken, S.

    Despite recent social and political advances, most interracial contact is still superficial in nature, and White individuals interact mainly with other Whites. Based on recent mere exposure research, we propose that repeated exposure to Whites may actually increase prejudice. In a series of

  16. Reproductive biology of black seabream Acanthopagrus schlegelii, threadfin porgy Evynnis cardinalis and red pargo Pagrus major in the northern South China Sea with consideration of fishery status and management needs.

    Science.gov (United States)

    Law, C S W; Sadovy de Mitcheson, Y

    2017-07-01

    The reproductive biology of three commercially significant seabream species (family: Sparidae) Acanthopagrus schlegelii, Evynnis cardinalis and Pagrus major, taken from Hong Kong and adjacent northern South China Sea (SCS) waters, were investigated for their sexual patterns, spawning seasons, length at maturity and exploitation in relation to their conservation and management status. Histological analysis showed E. cardinalis and P. major to be functionally gonochoristic, the latter having a bisexual juvenile stage and being a rudimentary hermaphrodite. Acanthopagrus schlegelii is a protandric hermaphrodite. Standard length (L S ) at 50% sex change for A. schlegelii is 291 mm. L S at 50% female maturity for E. cardinalis and P. major are 117 and 332 mm, respectively. For all three species, the spawning period falls between November and March. The study highlights geographical differences in reproductive biology among the species and a paucity of fishery or other population-related data. While heavy fishing pressure, life-history characteristics and absence of effective management throughout the geographic ranges of these species make them susceptible to overfishing, they nonetheless appear to be generally more resilient than many other taxa that comprise the multi-species fisheries of the region, possibly due to their relatively rapid sexual maturation and spatial movement patterns. Overall, however, little is known of the biology, fishing history and current fishery status of sparids in general in the northern SCS and the current study is one of the first to examine such aspects of this family in the region and to consider appropriate management options. © 2017 The Fisheries Society of the British Isles.

  17. Red flag on the white reporter: a versatile insulator abuts the white gene in Drosophila and is omnipresent in mini-white constructs.

    Science.gov (United States)

    Chetverina, Darya; Savitskaya, Ekaterina; Maksimenko, Oksana; Melnikova, Larisa; Zaytseva, Olga; Parshikov, Alexander; Galkin, Alexander V; Georgiev, Pavel

    2008-02-01

    Much of the research on insulators in Drosophila has been done with transgenic constructs using the white gene (mini-white) as reporter. Hereby we report that the sequence between the white and CG32795 genes in Drosophila melanogaster contains an insulator of a novel kind. Its functional core is within a 368 bp segment almost contiguous to the white 3'UTR, hence we name it as Wari (white-abutting resident insulator). Though Wari contains no binding sites for known insulator proteins and does not require Su(Hw) or Mod(mdg4) for its activity, it can equally well interact with another copy of Wari and with unrelated Su(Hw)-dependent insulators, gypsy or 1A2. In its natural downstream position, Wari reinforces enhancer blocking by any of the three insulators placed between the enhancer and the promoter; again, Wari-Wari, Wari-gypsy or 1A2-Wari pairing results in mutual neutralization (insulator bypass) when they precede the promoter. The distressing issue is that this element hides in all mini-white constructs employed worldwide to study various insulators and other regulatory elements as well as long-range genomic interactions, and its versatile effects could have seriously influenced the results and conclusions of many works.

  18. The galactic population of white dwarfs

    International Nuclear Information System (INIS)

    Napiwotzki, Ralf

    2009-01-01

    The contribution of white dwarfs of the different Galactic populations to the stellar content of our Galaxy is only poorly known. Some authors claim a vast population of halo white dwarfs, which would be in accordance with some investigations of the early phases of Galaxy formation claiming a top-heavy initial- mass- function. Here, I present a model of the population of white dwarfs in the Milky Way based on observations of the local white dwarf sample and a standard model of Galactic structure. This model will be used to estimate the space densities of thin disc, thick disc and halo white dwarfs and their contribution to the baryonic mass budget of the Milky Way. One result of this investigation is that white dwarfs of the halo population contribute a large fraction of the Galactic white dwarf number count, but they are not responsible for the lion's share of stellar mass in the Milky Way. Another important result is the substantial contribution of the - often neglected - population of thick disc white dwarfs. Misclassification of thick disc white dwarfs is responsible for overestimates of the halo population in previous investigations.

  19. A possible dominant white gene in Jersey cattle

    Directory of Open Access Journals (Sweden)

    Sponenberg D Phillip

    2001-01-01

    Full Text Available Abstract A white heifer ("Snow" was born in 1991 from coloured registered Jersey parents. She produced six calves sired by coloured Jersey bulls: three white bull calves, two white heifer calves, and one coloured bull calf. One of the white bull calves was mated with 40 Hereford × Friesian yearling heifers (white face, predominantly black body with some white patches. The 38 resulting calves included 16 white and 22 coloured calves. Twelve of the 16 white calves were heifers and four were bulls. Red or black spotting was recorded on some white calves. The results are consistent with an autosomal dominant mutant causing the white phenotype. The mutation appears to have arisen spontaneously in Snow, then passing to her white progeny and white grand-progeny. The white individuals varied from entirely white in a few cases, to most having some residual small areas of red or black pigmentation in patterns not typical of other reported white spotting patterns of cattle.

  20. White coat hypertension in pediatrics.

    Science.gov (United States)

    Jurko, Alexander; Minarik, Milan; Jurko, Tomas; Tonhajzerova, Ingrid

    2016-01-15

    The article summarizes current information on blood pressure changes in children during clinic visit. White coat as a general dressing of physicians and health care personnel has been widely accepted at the end of the 19th century. Two problems can be associated with the use of white coat: white coat phenomenon and white coat hypertension. Children often attribute pain and other unpleasant experience to the white coat and refuse afterwards cooperation with examinations. Definition of white coat hypertension in the literature is not uniform. It has been defined as elevated blood pressure in the hospital or clinic with normal blood pressure at home measured during the day by ambulatory blood pressure monitoring system. White coat effect is defined as temporary increase in blood pressure before and during visit in the clinic, regardless what the average daily ambulatory blood pressure values are. Clinical importance of white coat hypertension is mainly because of higher risk for cardiovascular accidents that are dependent on end organ damage (heart, vessels, kidney). Current data do not allow any clear recommendations for the treatment. Pharmacological therapy is usually started in the presence of hypertrophic left ventricle, changes in intimal/medial wall thickness of carotic arteries, microalbuminuria and other cardiovascular risk factors. Nonpharmacological therapy is less controversial and certainly more appropriate. Patients have to change their life style, need to eliminate as much cardiovascular risk factors as possible and sustain a regular blood pressure monitoring.

  1. Relationships between rodent white adipose fat pads and human white adipose fat depots

    Directory of Open Access Journals (Sweden)

    Daniella E. Chusyd

    2016-04-01

    Full Text Available The objective of this review was to compare and contrast the physiological and metabolic profiles of rodent white adipose fat pads with white adipose fat depots in humans. Human fat distribution and its metabolic consequences have received extensive attention, but much of what has been tested in translational research has relied heavily on rodents. Unfortunately, the validity of using rodent fat pads as a model of human adiposity has received less attention. There is a surprisingly lack of studies demonstrating an analogous relationship between rodent and human adiposity on obesity-related comorbidities. Therefore, we aimed to compare known similarities and disparities in terms of white adipose tissue development and distribution, sexual dimorphism, weight loss, adipokine secretion, and aging. While the literature supports the notion that many similarities exist between rodents and humans, notable differences emerge related to fat deposition and function of white adipose tissue. Thus, further research is warranted to more carefully define the strengths and limitations of rodent white adipose tissue as a model for humans, with a particular emphasis on comparable fat depots, such as mesenteric fat.

  2. Kootenai River White Sturgeon Investigations; White Sturgeon Spawning and Recruitment Evaluation, 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rust, Pete; Wakkinen, Virginia (Idaho Department of Fish and Game, Boise, ID)

    2005-06-01

    The objective of this research was to determine the environmental requirements for successful spawning and recruitment of the Kootenai River white sturgeon Acipenser transmontanus population. Annual tasks include monitoring and evaluating the various life stages of Kootenai River white sturgeon. Sampling for adult Kootenai River white sturgeon in 2003 began in March and continued through April. Eighty-one adult white sturgeon were captured with 3,576 hours of angling and set-lining effort in the Kootenai River. Discharge from Libby Dam and river stage at Bonners Ferry in 2003 peaked in May and early June. Flows remained above 500 m{sup 3}/s throughout June, decreased rapidly through mid July, and increased back to near 500 m{sup 3}/s after mid July and through mid August. By late August, flows had decreased to below 400 m{sup 3}/s. We monitored the movements of 24 adult sturgeon in Kootenay Lake, British Columbia (BC) and the Kootenai River from March 15, 2003 to August 31, 2003. Some of the fish were radio or sonic tagged in previous years. Twelve adult white sturgeon were moved upstream to the Hemlock Bar reach (rkm 260.0) and released as part of the Set and Jet Program. Transmitters were attached to seven of these fish, and their movements were monitored from the time of release until they moved downstream of Bonners Ferry. Eight additional radio-tagged white sturgeon adults were located in the traditional spawning reach (rkm 228-240) during May and June. Sampling with artificial substrate mats began May 21, 2003 and ended June 30, 2003. We sampled 717 mat d (a mat d is one 24 h set) during white sturgeon spawning. Three white sturgeon eggs were collected near Shortys Island on June 3, 2003, and five eggs were collected from the Hemlock Bar reach on June 5, 2003. Prejuvenile sampling began June 17, 2003 and continued until July 31, 2003. Sampling occurred primarily at Ambush Rock (rkm 244.0) in an attempt to document any recruitment that might have occurred from

  3. White constancy method for mobile displays

    Science.gov (United States)

    Yum, Ji Young; Park, Hyun Hee; Jang, Seul Ki; Lee, Jae Hyang; Kim, Jong Ho; Yi, Ji Young; Lee, Min Woo

    2014-03-01

    In these days, consumer's needs for image quality of mobile devices are increasing as smartphone is widely used. For example, colors may be perceived differently when displayed contents under different illuminants. Displayed white in incandescent lamp is perceived as bluish, while same content in LED light is perceived as yellowish. When changed in perceived white under illuminant environment, image quality would be degraded. Objective of the proposed white constancy method is restricted to maintain consistent output colors regardless of the illuminants utilized. Human visual experiments are performed to analyze viewers'perceptual constancy. Participants are asked to choose the displayed white in a variety of illuminants. Relationship between the illuminants and the selected colors with white are modeled by mapping function based on the results of human visual experiments. White constancy values for image control are determined on the predesigned functions. Experimental results indicate that propsed method yields better image quality by keeping the display white.

  4. Using a concentrate of phenols obtained from olive vegetation water to preserve chilled food: two case studies

    Directory of Open Access Journals (Sweden)

    Luca Fasolato

    2016-05-01

    Full Text Available Phenols are plant metabolites characterised by several interesting bioactive properties such as antioxidant and bactericidal activities. In this study the application of a phenols concentrate (PC from olive vegetation water to two different fresh products – gilt-head seabream (Sparus aurata and chicken breast – was described. Products were treated in a bath of PC (22 g/L; chicken breast or sprayed with two different solutions (L1:0.75 and L2:1.5 mg/mL; seabream and then stored under refrigeration conditions. The shelf life was monitored through microbiological analyses – quality index method for seabream and a specific sensory index for raw breast. The secondary products of lipid-peroxidation of the chicken breast were determined using the thiobarbituric acid reactive substances (TBARs test on cooked samples. Multivariate statistical techniques were adopted to investigate the impact of phenols and microbiological data were fitted by DMfit software. In seabream, the levels of PC did not highlight any significant difference on microbiological and sensory features. DMfit models suggested an effect only on H2S producing bacteria with an increased lag phase compared to the control samples (C: 87 h vs L2: 136 h. The results on chicken breast showed that the PC bath clearly modified the growth of Pseudomonas and Enterobacteriaceae. The phenol dipping was effective in limiting lipid-peroxidation (TBARs after cooking. Treated samples disclosed an increase of shelf life of 2 days. These could be considered as preliminary findings suggesting the use of this concentrate as preservative in some fresh products.

  5. Endogenous retrovirus insertion in the KIT oncogene determines white and white spotting in domestic cats.

    Science.gov (United States)

    David, Victor A; Menotti-Raymond, Marilyn; Wallace, Andrea Coots; Roelke, Melody; Kehler, James; Leighty, Robert; Eizirik, Eduardo; Hannah, Steven S; Nelson, George; Schäffer, Alejandro A; Connelly, Catherine J; O'Brien, Stephen J; Ryugo, David K

    2014-08-01

    The Dominant White locus (W) in the domestic cat demonstrates pleiotropic effects exhibiting complete penetrance for absence of coat pigmentation and incomplete penetrance for deafness and iris hypopigmentation. We performed linkage analysis using a pedigree segregating White to identify KIT (Chr. B1) as the feline W locus. Segregation and sequence analysis of the KIT gene in two pedigrees (P1 and P2) revealed the remarkable retrotransposition and evolution of a feline endogenous retrovirus (FERV1) as responsible for two distinct phenotypes of the W locus, Dominant White, and white spotting. A full-length (7125 bp) FERV1 element is associated with white spotting, whereas a FERV1 long terminal repeat (LTR) is associated with all Dominant White individuals. For purposes of statistical analysis, the alternatives of wild-type sequence, FERV1 element, and LTR-only define a triallelic marker. Taking into account pedigree relationships, deafness is genetically linked and associated with this marker; estimated P values for association are in the range of 0.007 to 0.10. The retrotransposition interrupts a DNAase I hypersensitive site in KIT intron 1 that is highly conserved across mammals and was previously demonstrated to regulate temporal and tissue-specific expression of KIT in murine hematopoietic and melanocytic cells. A large-population genetic survey of cats (n = 270), representing 30 cat breeds, supports our findings and demonstrates statistical significance of the FERV1 LTR and full-length element with Dominant White/blue iris (P < 0.0001) and white spotting (P < 0.0001), respectively. Copyright © 2014 David et al.

  6. Asteroseismology of White Dwarf Stars

    Science.gov (United States)

    Hansen, Carl J.

    1997-01-01

    The primary purpose of this investigation has been to study various aspects of multimode pulsations in variable white dwarfs. In particular, nonlinear interactions among pulsation modes in white dwarfs (and, to some extent, in other variable stars), analysis of recent observations where such interactions are important, and preliminary work on the effects of crystallization in cool white dwarfs are reported.

  7. Genetics Home Reference: white sponge nevus

    Science.gov (United States)

    ... Twitter Home Health Conditions White sponge nevus White sponge nevus Printable PDF Open All Close All Enable ... to view the expand/collapse boxes. Description White sponge nevus is a condition characterized by the formation ...

  8. White dwarfs - the once and future suns

    International Nuclear Information System (INIS)

    Trimble, V.

    1986-01-01

    The history and properties of white dwarfs (Bessel's conclusion that Sirius and Procyon have invisible companions, Clark's discovery of Sirius B, Adams and Russell's study of white dwarf spectra, Chandrasekhar's explanation of white dwarf structure by equations incorporating quantum mechanics and relativity) are treated. Formation of white dwarfs, degeneracy, binary white dwarfs (and novae and supernovae) are explained. A mystery nearly 50 years old regarding the spectrum of the star Greenwich +70 degrees-8247 has been solved: it involves a stationary line phenomenon and a magnetic field of 300-500 million gauss. Processes being studied in white dwarfs and white dwarf models include gravitational settling, accretion, dredge-up, radiation pressure, and diffusive hydrogen burning

  9. SDSS DR7 WHITE DWARF CATALOG

    Energy Technology Data Exchange (ETDEWEB)

    Kleinman, S. J.; Nitta, A. [Gemini Observatory, 670 North A' ohoku Place, Hilo, HI 96720 (United States); Kepler, S. O.; Pelisoli, Ingrid; Pecanha, Viviane; Costa, J. E. S. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Koester, D. [Institut fuer Theoretische Physik und Astrophysik, Universitaet Kiel, D-24098 Kiel (Germany); Krzesinski, J. [Mt. Suhora Observatory, Pedagogical University of Cracow, ul. Podchorazych 2, 30-084 Cracow (Poland); Dufour, P.; Lachapelle, F.-R.; Bergeron, P. [Departement de Physique, Universite de Montreal, C. P. 6128, Succ. Centre-Ville, Montreal, Quebec H3C 3J7 (Canada); Yip, Ching-Wa [Department of Physics and Astronomy, The Johns Hopkins University, 3701 San Martin Drive, Baltimore, MD 21218 (United States); Harris, Hugh C. [United States Naval Observatory, Flagstaff Station, 10391 West Naval Observatory Road, Flagstaff, AZ 86001-8521 (United States); Eisenstein, Daniel J. [Harvard Smithsonian Center for Astrophysics, 60 Garden Street, MS 20, Cambridge, MA 02138 (United States); Althaus, L.; Corsico, A., E-mail: hch@nofs.navy.mil [Facultad de Ciencias Astronomicas y Geofisicas, Paseo del Bosque S/N, (1900) La Plata (Argentina)

    2013-01-15

    We present a new catalog of spectroscopically confirmed white dwarf stars from the Sloan Digital Sky Survey (SDSS) Data Release 7 spectroscopic catalog. We find 20,407 white dwarf spectra, representing 19,712 stars, and provide atmospheric model fits to 14,120 DA and 1011 DB white dwarf spectra from 12,843 and 923 stars, respectively. These numbers represent more than a factor of two increase in the total number of white dwarf stars from the previous SDSS white dwarf catalogs based on DR4 data. Our distribution of subtypes varies from previous catalogs due to our more conservative, manual classifications of each star in our catalog, supplementing our automatic fits. In particular, we find a large number of magnetic white dwarf stars whose small Zeeman splittings mimic increased Stark broadening that would otherwise result in an overestimated log g if fit as a non-magnetic white dwarf. We calculate mean DA and DB masses for our clean, non-magnetic sample and find the DB mean mass is statistically larger than that for the DAs.

  10. Hypermedicalization in White Noise.

    Science.gov (United States)

    Benson, Josef

    2015-09-01

    The Nazis hijacked Germany's medical establishment and appropriated medical language to hegemonize their ideology. In White Noise, shifting medical information stifles the public into docility. In Nazi Germany the primacy of language and medical authority magnified the importance of academic doctors. The muddling of identities caused complex insecurities and the need for psychological doubles. In White Noise, Professor Gladney is driven by professional insecurities to enact a double in Murray. Through the manipulation of language and medical overreach the U.S., exemplified in the novel White Noise, has become a hypermedicalized society where the spirit of the Hippocratic Oath has eroded.

  11. When White Women Cry: How White Women's Tears Oppress Women of Color

    Science.gov (United States)

    Accapadi, Mamta Motwani

    2007-01-01

    This article focuses on the tension that arises as the result of the intersection of social identities, namely gender and race. Through examination of a case study I consider the ways in which White women benefit from White privilege through their interactions with Women of Color using the Privileged Identity Exploration Model as the tool for…

  12. The mouthfeel of white wine.

    Science.gov (United States)

    Gawel, Richard; Smith, Paul A; Cicerale, Sara; Keast, Russell

    2017-07-05

    White wine mouthfeel which encompasses the tactile, chemosensory and taste attributes of perceived viscosity, astringency, hotness and bitterness is increasingly being recognized as an important component of overall white wine quality. This review summarizes the physiological basis for the perception of white wine mouthfeel and the direct and interactive effects of white wine composition, specifically those of low molecular weight phenolic compounds, polysaccharides, pH, ethanol, glycerol, dissolved carbon dioxide, and peptides. Ethyl alcohol concentration and pH play a direct role in determining most aspects of mouthfeel perception, and provide an overall framework on which the other minor wine components can interact to influence white wine mouthfeel. Phenolic compounds broadly impact on the mouthfeel by contributing to its viscosity, astringency, hotness and bitterness. Their breadth of influence likely results from their structural diversity which would allow them to activate multiple sensory mechanisms involved in mouthfeel perception. Conversely, polysaccharides have a small modulating effect on astringency and hotness perception, and glycerol does not affect perceived viscosity within the narrow concentration range found in white wine. Many of the major sensory attributes that contribute to the overall impression of mouthfeel are elicited by more than one class compound suggesting that different physiological mechanisms may be involved in the construct of mouthfeel percepts.

  13. Lowering the glycemic index of white bread using a white bean extract.

    Science.gov (United States)

    Udani, Jay K; Singh, Betsy B; Barrett, Marilyn L; Preuss, Harry G

    2009-10-28

    Phase 2((R)) is a dietary supplement derived from the common white kidney bean (Phaseolus vulgaris). Phase 2 has been shown to inhibit alpha-amylase, the complex carbohydrate digesting enzyme, in vitro. The inhibition of alpha-amylase may result in the lowering of the effective Glycemic Index (GI) of certain foods. The objective of this study was to determine whether the addition of Phase 2 would lower the GI of a commercially available high glycemic food (white bread). An open-label 6-arm crossover study was conducted with 13 randomized subjects. Standardized GI testing was performed on white bread with and without the addition of Phase 2 in capsule and powder form, each in dosages of 1500 mg, 2000 mg, and 3000 mg. Statistical analysis was performed by one-way ANOVA of all seven treatment groups using unadjusted multiple comparisons (t tests) to the white bread control. For the capsule formulation, the 1500 mg dose had no effect on the GI and the 2000 mg and 3000 mg capsule doses caused insignificant reductions in GI. For the powder, the 1500 mg and 2000 mg doses caused insignificant reductions in the GI, and the 3000 mg dose had a significant effect (-20.23 or 34.11%, p = 0.023) Phase 2 white bean extract appears to be a novel and potentially effective method for reducing the GI of existing foods without modifying their ingredient profile. Trial Registration: ISRCTN50347345.

  14. Selected fishery and population parameters of eight shore-angling ...

    African Journals Online (AJOL)

    Selected fishery and population parameters of eight shore-angling species in the ... Five different estimates of natural mortality (M), and the coefficients of ... for the most abundant species, blacktail Diplodus capensis, with a mean CPUE of 0.252 ... Keywords: catch per unit effort; fisheries management; marine protected area; ...

  15. Pulsations in white dwarf stars

    OpenAIRE

    Van Grootel, Valérie; Fontaine, Gilles; Brassard, Pierre; Dupret, Marc-Antoine

    2017-01-01

    I will present a description of the six distinct families of pulsating white dwarfs that are currently known. Pulsations are present at various stages of the evolution (from hot, pre-white dwarfs to cool white dwarfs), at various stellar masses, and for various atmospheric compositions. In all of them, a mechanism linked to opacity changes along the evolution drives the oscillations. The existence of these oscillations offers the opportunity to apply asteroseismology for constraining physics ...

  16. Biomarkers in white-coat hypertension

    OpenAIRE

    Martin, Catherine Ann

    2017-01-01

    The introduction of ambulatory blood pressure monitoring in the 1960s provided new insights into the nature of high blood pressure disorders. Blood pressure is now categorised into four quadrants:normotension, masked hypertension, hypertension and white-coat hypertension. In white-coat hypertension blood pressure is elevated when taken at the doctor’s office but normal if taken outside the doctor’s office. Several controversies are associated with white-coat hypertension, which are discuss...

  17. Evolution models of helium white dwarf-main-sequence star merger remnants: the mass distribution of single low-mass white dwarfs

    Science.gov (United States)

    Zhang, Xianfei; Hall, Philip D.; Jeffery, C. Simon; Bi, Shaolan

    2018-02-01

    It is not known how single white dwarfs with masses less than 0.5Msolar -- low-mass white dwarfs -- are formed. One way in which such a white dwarf might be formed is after the merger of a helium-core white dwarf with a main-sequence star that produces a red giant branch star and fails to ignite helium. We use a stellar-evolution code to compute models of the remnants of these mergers and find a relation between the pre-merger masses and the final white dwarf mass. Combining our results with a model population, we predict that the mass distribution of single low-mass white dwarfs formed through this channel spans the range 0.37 to 0.5Msolar and peaks between 0.45 and 0.46Msolar. Helium white dwarf--main-sequence star mergers can also lead to the formation of single helium white dwarfs with masses up to 0.51Msolar. In our model the Galactic formation rate of single low-mass white dwarfs through this channel is about 8.7X10^-3yr^-1. Comparing our models with observations, we find that the majority of single low-mass white dwarfs (<0.5Msolar) are formed from helium white dwarf--main-sequence star mergers, at a rate which is about $2$ per cent of the total white dwarf formation rate.

  18. Blanco White and Walter Scott Blanco white y Walter Scott

    Directory of Open Access Journals (Sweden)

    Fernando DURÁN LÓPEZ

    2011-01-01

    Full Text Available The first edition of Ivanhoe; a romance. By the author of Waverley was published in Edinburgh in 1820. From the beginning of year 1823, José María Blanco White translated several excerpts from Ivanhoe in the numbers 1-3 of the magazine Variedades, owned by the publisher Rudolph Ackermann. in these articles and other later writings, the translator praised Scott as a model for a new way of painting history in a narrative. This paper studies his ideas on Scott’s historical novel, as well as his translation technique, compared with that of José Joaquín de Mora. En 1820 se publicó en Edimburgo la primera edición de Ivanhoe; a romance. By the author of Waverley. Desde comienzos de 1823, en los tres primeros números de su revista Variedades, promovida por el editor Rudolph Ackermann, José María Blanco White tradujo varios fragmentos de Ivanhoe entre grandes elogios. Asimismo, Blanco White tomó a Scott como modelo de referencia de una nueva manera de pintar la historia por medio de la novela en otros varios escritos críticos de años posteriores. El artículo estudia las ideas de Blanco White acerca de la novela histórica de Scott y su técnica como traductor, comparada con la de José Joaquín Mora.

  19. Infrared photometry of cool white dwarfs

    International Nuclear Information System (INIS)

    Wickramasinghe, D.T.; Allen, D.A.; Bessell, M.S.

    1982-01-01

    The results are presented of a search for the effects of pressure induced H 2 dipole opacity on the infrared JHK magnitudes of cool white dwarfs. LHS 1126 is found to be a very cool (Tsub(e) approximately 4250 K) DC white dwarf with a H rich atmospheric composition dominated by H 2 dipole opacity in the infrared. JHK photometry also favours a H rich atmospheric composition for the DK white dwarfs LP 658-2 and W 489. The surprisingly high proportion of hydrogen rich white dwarfs in the sample appears to suggest that the mechanism which inhibits the accretion of hydrogen in the hotter helium stars becomes less effective at low (Tsub(e) approximately 3 + ion in cool hydrogen rich white dwarf atmospheres is pointed out and it is suggested that the opacity due to this ion may be responsible for the blanketing observed in the U and B magnitudes of some cool white dwarfs. (author)

  20. Morale, Participation and Shortage in White-Majority and White-Minority Schools: Principals' Perceptions

    Science.gov (United States)

    Cheema, Jehanzeb R.; Fuller Hamilton, Asia N.

    2017-01-01

    Prior research has shown that teacher-centred factors such as teacher participation in decision making, teacher morale, and shortage of teaching staff, can affect school performance. In this study we examined how these factors differ between White-majority and White-minority schools both before and after controlling for school characteristics such…

  1. White-dwarf-white-dwarf galactic background in the LISA data

    International Nuclear Information System (INIS)

    Edlund, Jeffrey A.; Tinto, Massimo; Krolak, Andrzej; Nelemans, Gijs

    2005-01-01

    LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own Galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. Our approach relies on entirely analytic expressions of the LISA time-delay interferometric responses to the gravitational radiation emitted by such systems, which allows us to implement a computationally efficient and accurate simulation of the background in the LISA data. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. This suggests that, during this time period, LISA could search for other gravitational wave signals incoming from directions that are away from the galactic plane. Since the galactic white-dwarf background will be observed by LISA not as a stationary but rather as a cyclostationary random process with a period of 1 yr, we summarize the theory of cyclostationary random processes, present the corresponding generalized spectral method needed to characterize such process, and make a comparison between our analytic results and those obtained by applying our method to the simulated data. We find that, by measuring the generalized spectral components of the white-dwarf background, LISA will be able to infer properties of the distribution of the white-dwarf binary systems present in our Galaxy

  2. 21 CFR 160.145 - Dried egg whites.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Dried egg whites. 160.145 Section 160.145 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.145 Dried egg whites. (a) The food dried egg whites, egg white solids, dried egg albumen, egg albumen solids is...

  3. Lowering the glycemic index of white bread using a white bean extract

    Directory of Open Access Journals (Sweden)

    Singh Betsy B

    2009-10-01

    Full Text Available Abstract Background Phase 2® is a dietary supplement derived from the common white kidney bean (Phaseolus vulgaris. Phase 2 has been shown to inhibit alpha-amylase, the complex carbohydrate digesting enzyme, in vitro. The inhibition of alpha-amylase may result in the lowering of the effective Glycemic Index (GI of certain foods. The objective of this study was to determine whether the addition of Phase 2 would lower the GI of a commercially available high glycemic food (white bread. Methods An open-label 6-arm crossover study was conducted with 13 randomized subjects. Standardized GI testing was performed on white bread with and without the addition of Phase 2 in capsule and powder form, each in dosages of 1500 mg, 2000 mg, and 3000 mg. Statistical analysis was performed by one-way ANOVA of all seven treatment groups using unadjusted multiple comparisons (t tests to the white bread control. Results For the capsule formulation, the 1500 mg dose had no effect on the GI and the 2000 mg and 3000 mg capsule doses caused insignificant reductions in GI. For the powder, the 1500 mg and 2000 mg doses caused insignificant reductions in the GI, and the 3000 mg dose had a significant effect (-20.23 or 34.11%, p = 0.023 Conclusion Phase 2 white bean extract appears to be a novel and potentially effective method for reducing the GI of existing foods without modifying their ingredient profile. Trial Registration Trial Registration: ISRCTN50347345

  4. Multiculturalism, Teaching Slavery, and White Supremacy

    Science.gov (United States)

    Bery, Sadhana

    2014-01-01

    This article argues that multiculturalism, especially when it is led and controlled by Whites, and in the absence of collective anti-racist struggles, can reproduce the ontologies, epistemologies, and practices of white supremacy. I use a case study of a reenactment of Atlantic black slavery, produced by white teachers to investigate whether…

  5. 21 CFR 163.124 - White chocolate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false White chocolate. 163.124 Section 163.124 Food and... CONSUMPTION CACAO PRODUCTS Requirements for Specific Standardized Cacao Products § 163.124 White chocolate. (a) Description. (1) White chocolate is the solid or semiplastic food prepared by intimately mixing and grinding...

  6. 21 CFR 137.265 - Degerminated white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated white corn meal. 137.265 Section 137... Cereal Flours and Related Products § 137.265 Degerminated white corn meal. (a) Degerminated white corn meal, degermed white corn meal, is the food prepared by grinding cleaned white corn and removing bran...

  7. Feeding habits of Pagellus acarne (Sparidae in the Gulf of Tunis, central Mediterranean

    Directory of Open Access Journals (Sweden)

    Rafika Fehri-Bedoui

    2009-12-01

    Full Text Available The feeding habits of the axillary seabream, Pagellus acarne (Risso, 1810, from the Gulf of Tunis were investigated in relation to season, sex and fish size (juveniles TL < 14.5 cm and adults TL ≥ 14.5 cm. A total of 536 specimens (males, females, unsexed and hermaphroditic, ranging between 11.0 and 25.2 cm TL, were collected with trammel nets from June 2005 to July 2006. Their stomach contents were analysed. Of the total number of examined stomachs, 279 stomachs were empty (Vacuity index, VI = 52%. The VI did not reveal significant seasonal differences when all of the specimens were analysed together; however, significant seasonal variations were observed for females. The diet of the axillary seabream was composed of 36 different prey species. The most important prey were Arthropoda, Mollusca and Echinodermata. Both the dietary indices and the Spearman’s coefficient of correlation indicated seasonal variations in the diet. The diet was more diversified in adults than in juveniles. The axillary seabream fed on a wide range of prey items, endofauna and nekton, and can be considered a carnivorous and euryphagous predator.

  8. THE WHITE BLOOD ANCESTOR?

    OpenAIRE

    M.Arulmani; V.R.Hema Latha

    2014-01-01

    This scientific research article focus that “Red colour blood” of human shall be considered as the 3rd generation Blood and the Human on origin shall be considered having white colour Blood. The white colour blood of human Ancestor shall be considered composed of only ions of Photon, Electron, Proton and free from Hydrogen, Carbon, Nitrogen, Ozone.

  9. The White Sea, Russia

    Science.gov (United States)

    2002-01-01

    Editor's Note: The caption below, published on May 10, 2001, is incorrect. According to Masha Vorontsova, director of the International Fund for Animal Welfare in Moscow, the situation with the seal pups in the White Sea is normal. There is no disaster and there never was. For more details, refer to the article entitled 'No Danger' on the New Scientist home page. The Earth Observatory regrets the earlier errant report. Original Caption According to the Russian Polar Research Institute for Fisheries and Oceanography, between 250,000 and 300,000 Greenland seal pups face death by starvation over the next two months due to a cruel trick by mother nature. The seals, most of them less than two months old, are trapped on ice sheets that remain locked in the White Sea, located near Archangel in Northern Russia. Typically, during the spring thaw the ice sheets break up and flow with the currents northward into the Barents Sea, the seals' spring feeding grounds. The seal pups hitch a ride on the ice floes, living on their own individual stores of fat until they arrive in the Barents Sea. Their mothers departed for the Barents Sea weeks ago. In a normal year, the seal pups' trip from the White Sea out to the Barents takes about six weeks and the seals have adapted to rely upon this mechanism of mother nature. During their yearly migration, the mother seals usually stay with their pups and feed them until their pelts turn from white to grey--a sign that the pups are mature enough to swim and feed themselves. Unfortunately, this year unusually strong northerly winds created a bottleneck of ice near the mouth of the white sea, thus blocking the flow of ice and trapping the pups. These true-color images of the White Sea were acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. This image, taken May 2, 2000 that there is usually much less ice in the White Sea this time of year as most of it is typically en route to the

  10. An analysis of the recreational shore fishery in the Goukamma ...

    African Journals Online (AJOL)

    Ten years (1993–2002) of shore fishing catch and effort data collected during routine patrols in the Goukamma Marine Protected Area in theWestern Cape Province were analysed. Of a total of 35 species recorded, the most common were backtail, Diplodus sargus capensis (39%), and galjoen, Dichistius capensis (25%).

  11. WHITE BLISTER SPECIES (Albuginaceae ON WEEDS

    Directory of Open Access Journals (Sweden)

    Karolina Vrandečić

    2011-06-01

    Full Text Available The obligate fungi inside the family Albuginaceae are widespread world wide and cause white rust or white blister disease. Mycopopulation of weeds has been researched within the project „The role of weeds in epidemiology of row-crop diseases“. The aim of this research was to identify white blister species occurring on weeds in Eastern Croatia. Weed plants with disease symptoms characteristic for white blister species have been collected since 2001 on location Slavonia and Baranja country. Determination of white blister species was based on morphological characters of pathogen and the host. Wilsoniana bliti was determined on Amaranthus retroflexus and Amaranthus hybridus leaves. Capsella bursa pastoris is a host for Albugo candida. Ambrosia artemisiifolia is a host for Pustula sp. and Cirsium arvense was found to be host for Pustula spinulosa. Wilsoniana portulaceae was determined on Portulaca oleracea.

  12. Wolff-Parkinson-White Syndrome and Accessory Pathways

    Science.gov (United States)

    ... the American Heart Association Cardiology Patient Page Wolff-Parkinson-White Syndrome and Accessory Pathways James Kulig , Bruce ... rate, which can be dangerous. What is Wolff-Parkinson-White Syndrome? Wolff-Parkinson-White syndrome (WPW) is ...

  13. An overview of white dwarf stars

    Directory of Open Access Journals (Sweden)

    Charpinet S.

    2013-03-01

    Full Text Available We present a brief summary of what is currently known about white dwarf stars, with an emphasis on their evolutionary and internal properties. As is well known, white dwarfs represent the end products of stellar evolution for the vast majority of stars and, as such, bear the signatures of past events (such as mass loss, mixing phases, loss and redistribution of angular momentum, and thermonuclear burning that are of essential importance in the evolution of stars in general. In addition, white dwarf stars represent ideal testbeds for our understanding of matter under extreme conditions, and work on their constitutive physics (neutrino production rates, conductive and radiative opacities, interior liquid/solid equations of state, partially ionized and partially degenerate envelope equations of state, diffusion coefficients, line broadening mechanisms is still being actively pursued. Given a set of constitutive physics, cooling white dwarfs can be used advantageously as cosmochronometers. Moreover, the field has been blessed by the existence of four distinct families of pulsating white dwarfs, each mapping a different evolutionary phase, and this allows the application of the asteroseismological method to probe and test their internal structure and evolutionary state. We set the stage for the reviews that follow on cooling white dwarfs as cosmochronometers and physics laboratories, as well as on the properties of pulsating white dwarfs and the asteroseismological results that can be inferred.

  14. How bees distinguish black from white

    Directory of Open Access Journals (Sweden)

    Horridge A

    2014-10-01

    Full Text Available Adrian Horridge Biological Sciences, Australian National University, Canberra, ACT, AustraliaAbstract: Bee eyes have photoreceptors for ultraviolet, green, and blue wavelengths that are excited by reflected white but not by black. With ultraviolet reflections excluded by the apparatus, bees can learn to distinguish between black, gray, and white, but theories of color vision are clearly of no help in explaining how they succeed. Human vision sidesteps the issue by constructing black and white in the brain. Bees have quite different and accessible mechanisms. As revealed by extensive tests of trained bees, bees learned two strong signals displayed on either target. The first input was the position and a measure of the green receptor modulation at the vertical edges of a black area, which included a measure of the angular width between the edges of black. They also learned the average position and total amount of blue reflected from white areas. These two inputs were sufficient to help decide which of two targets held the reward of sugar solution, but the bees cared nothing for the black or white as colors, or the direction of contrast at black/white edges. These findings provide a small step toward understanding, modeling, and implementing in silicon the anti-intuitive visual system of the honeybee, in feeding behavior. Keywords: vision, detectors, black/white, color, visual processing

  15. Toxicity of White Snakeroot (Ageratina altissima) and chemical extracts of White Snakeroot in goats

    Science.gov (United States)

    White snakeroot (Ageratina altissima) is a sporadically toxic plant that causes trembles in livestock and milk sickness in humans that drink tainted milk. The putative toxin in white snakeroot is tremetone and possibly other benzofuran ketones even though it has not been demonstrated in vivo. Toxi...

  16. PREFACE: 16th European White Dwarfs Workshop

    Science.gov (United States)

    Garcia-Berro, Enrique; Hernanz, Margarita; Isern, Jordi; Torres, Santiago

    2009-07-01

    The 16th European Workshop on White Dwarfs was held in Barcelona, Spain, from 30 June to 4 July 2008 at the premises of the UPC. Almost 120 participants from Europe (France, Germany, United Kingdom, Italy, and several others), America (USA, Canada, Argentina, Brazil, and Chile), and other continents (Australia, South Africa, . . . ) attended the workshop. Among these participants were the most relevant specialists in the field. The topics covered by the conference were: White dwarf structure and evolution Progenitors and Planetary Nebulae White dwarfs in binaries: cataclysmic variables, double degenerates and other binaries White dwarfs, dust disks and planetary systems Atmospheres, chemical composition, magnetic fields Variable white dwarfs White dwarfs in stellar clusters and the halo White Dwarfs as SNIa progenitors The programme included 54 talks, and 45 posters. The oral presentations were distributed into the following sessions: Luminosity function, mass function and populations White dwarf structure and evolution White dwarf ages White dwarf catalogs and surveys Central stars of planetary nebulae Supernovae progenitors White dwarfs in novae and CVs Physical processes in white dwarfs and magnetic white dwarfs Disks, dust and planets around white dwarfs Pulsating white dwarfs Additionally we had a special open session about Spitzer and white dwarfs. The Proceedings of the 16th European Workshop on White Dwarfs are representative of the current state-of-the-art of the research field and include new and exciting results. We acknowledge the very positive attitude of the attendants to the workshop, which stimulated very fruitful discussions that took place in all the sessions and after the official schedule. Also, the meeting allowed new collaborations tp start that will undoubtedly result in significant advances in the research field. We also acknowledge the willingness of the participants to deliver their contributions before the final deadline. We sincerely

  17. Concept of white light in stage lighting

    Science.gov (United States)

    Rinaldi, Mauricio R.

    2002-06-01

    In perceiving objects, generally we see them in a white light situation. But, actually, there is not an absolute white, in such a manner that the different light sources have a determined kind of white, what it is known as color temperature. Even the white light may be of different kinds (different color temperature), the individual mind tends to perceive it as the same kind of white, that is to say, there is in our mind a psychological function by which we operate an integration in the perception in order to do the object perceptually invariable. On the other hand, it is a common practice in stage lighting to use color light sources. It is a well known phenomenon that a color of light produces a change in the object color perception. However, when we go to theater, we see the objects as having their real color, even if the lighting is not white. In this paper the concept of white light in stage lighting is presented, showing its possibilities of aesthetical expression.

  18. Merging white dwarfs and thermonuclear supernovae.

    Science.gov (United States)

    van Kerkwijk, M H

    2013-06-13

    Thermonuclear supernovae result when interaction with a companion reignites nuclear fusion in a carbon-oxygen white dwarf, causing a thermonuclear runaway, a catastrophic gain in pressure and the disintegration of the whole white dwarf. It is usually thought that fusion is reignited in near-pycnonuclear conditions when the white dwarf approaches the Chandrasekhar mass. I briefly describe two long-standing problems faced by this scenario, and the suggestion that these supernovae instead result from mergers of carbon-oxygen white dwarfs, including those that produce sub-Chandrasekhar-mass remnants. I then turn to possible observational tests, in particular, those that test the absence or presence of electron captures during the burning.

  19. White Light Photorefractive Phase Zone Plates

    International Nuclear Information System (INIS)

    Yuan-Mei, Gao; Si-Min, Liu

    2008-01-01

    Incoherent white light from an incandescent source is employed to fabricate volume phase zone plates in LiNbO 3 : Fe, for the first time to our knowledge, which can guide and modulate the input white light or laser light. The diffractive efficiency of the white light volume phase zone plates fabricated can reach as high as 12%. In addition, we test the volume phase zone plates by a probe beam and find that the volume phase zone plate is present in the direction perpendicular to the c-axis and absent in the direction parallel to the c-axis. This directly proves the existence of photovoltaic photorefractive anisotropy of white light

  20. Opportunities in white-box cryptography

    NARCIS (Netherlands)

    Michiels, W.

    White-box cryptography is the discipline of implementing a cryptographic algorithm in software such that an adversary will have difficulty extracting the cryptographic key. This approach assumes that the adversary has full access to and full control over the implementation's execution. White-box

  1. Pulsations in carbon-atmosphere white dwarfs: A new chapter in white dwarf asteroseismology

    International Nuclear Information System (INIS)

    Fontaine, G; Brassard, P; Dufour, P; Green, E M; Liebert, J

    2009-01-01

    We present some of the results of a survey aimed at exploring the asteroseismological potential of the newly-discovered carbon-atmosphere white dwarfs. We show that, in certains regions of parameter space, carbon-atmosphere white dwarfs may drive low-order gravity modes. We demonstrate that our theoretical results are consistent with the recent exciting discovery of luminosity variations in SDSS J1426+5752 and some null results obtained by a team of scientists at McDonald Observatory. We also present follow-up photometric observations carried out by ourselves at the Mount Bigelow 1.6-m telescope using the new Mont4K camera. The results of follow-up spectroscopic observations at the MMT are also briefly reported, including the surprising discovery that SDSS J1426+5752 is not only a pulsating star but that it is also a magnetic white dwarf with a surface field near 1.2 MG. The discovery of g-mode pulsations in SDSS J1426+5752 is quite significant in itself as it opens a fourth asteroseismological 'window', after the GW Vir, V777 Her, and ZZ Ceti families, through which one may study white dwarfs.

  2. White Privilege, Psychoanalytic Ethics, and the Limitations of ...

    African Journals Online (AJOL)

    Whereas the critique of whiteness involves both philosophical and psychological scrutiny, subsequent calls for white political silence and withdrawal have yet to be ... These concepts throw a critical light on disavowals of white privilege and provide a novel means of thinking how white narcissism might be relinquished.

  3. A radio-pulsing white dwarf binary star.

    Science.gov (United States)

    Marsh, T R; Gänsicke, B T; Hümmerich, S; Hambsch, F-J; Bernhard, K; Lloyd, C; Breedt, E; Stanway, E R; Steeghs, D T; Parsons, S G; Toloza, O; Schreiber, M R; Jonker, P G; van Roestel, J; Kupfer, T; Pala, A F; Dhillon, V S; Hardy, L K; Littlefair, S P; Aungwerojwit, A; Arjyotha, S; Koester, D; Bochinski, J J; Haswell, C A; Frank, P; Wheatley, P J

    2016-09-15

    White dwarfs are compact stars, similar in size to Earth but approximately 200,000 times more massive. Isolated white dwarfs emit most of their power from ultraviolet to near-infrared wavelengths, but when in close orbits with less dense stars, white dwarfs can strip material from their companions and the resulting mass transfer can generate atomic line and X-ray emission, as well as near- and mid-infrared radiation if the white dwarf is magnetic. However, even in binaries, white dwarfs are rarely detected at far-infrared or radio frequencies. Here we report the discovery of a white dwarf/cool star binary that emits from X-ray to radio wavelengths. The star, AR Scorpii (henceforth AR Sco), was classified in the early 1970s as a δ-Scuti star, a common variety of periodic variable star. Our observations reveal instead a 3.56-hour period close binary, pulsing in brightness on a period of 1.97 minutes. The pulses are so intense that AR Sco's optical flux can increase by a factor of four within 30 seconds, and they are also detectable at radio frequencies. They reflect the spin of a magnetic white dwarf, which we find to be slowing down on a 10 7 -year timescale. The spin-down power is an order of magnitude larger than that seen in electromagnetic radiation, which, together with an absence of obvious signs of accretion, suggests that AR Sco is primarily spin-powered. Although the pulsations are driven by the white dwarf's spin, they mainly originate from the cool star. AR Sco's broadband spectrum is characteristic of synchrotron radiation, requiring relativistic electrons. These must either originate from near the white dwarf or be generated in situ at the M star through direct interaction with the white dwarf's magnetosphere.

  4. Evolution models of helium white dwarf--main-sequence star merger remnants: the mass distribution of single low-mass white dwarfs

    OpenAIRE

    Zhang, Xianfei; Hall, Philip D.; Jeffery, C. Simon; Bi, Shaolan

    2017-01-01

    It is not known how single white dwarfs with masses less than 0.5Msolar -- low-mass white dwarfs -- are formed. One way in which such a white dwarf might be formed is after the merger of a helium-core white dwarf with a main-sequence star that produces a red giant branch star and fails to ignite helium. We use a stellar-evolution code to compute models of the remnants of these mergers and find a relation between the pre-merger masses and the final white dwarf mass. Combining our results with ...

  5. Eating pathology among Black and White smokers.

    Science.gov (United States)

    Sánchez-Johnsen, Lisa A P; Fitzgibbon, Marian L; Ahluwalia, Jasjit S; Spring, Bonnie J

    2005-02-01

    Among White smokers, many females use smoking as a weight control strategy. Little is known about the relationship between eating pathology and smoking among Black females, and whether smokers who enroll in treatment differ in eating pathology from smokers who decline treatment. We examined eating pathology among Black and White smokers who enrolled in a smoking cessation treatment and those who declined treatment. Participants were 100 Black and 100 White female smokers (ages 18-65) who completed three measures of eating pathology. After controlling for BMI, Whites reported greater levels of overall eating pathology than Blacks [F(1,195)=4.1; pWhite than Black smokers. However, once females seek smoking cessation treatment, these ethnic differences are not apparent.

  6. Progenitors of white dwarfs

    International Nuclear Information System (INIS)

    Drilling, J.S.; Schoenberner, D.

    1985-01-01

    Direct observational evidence is presented which indicates that the immediate progenitors of white dwarfs are the central stars of planetary nebulae (approximately 70%), other post-AGB objects (approximately 30%), and post-HB objects not massive enough to climb the AGB (approximately 0.3%). The combined birth rate for these objects is in satisfactory agreement with the death rate of main-sequence stars and the birth rate of white dwarfs

  7. On the symbolism of the white coat.

    Science.gov (United States)

    Nash, David A

    2014-12-01

    The white coat ceremony has become an academic ritual in the health professions: a ceremony that signals a transformation of status from ordinary student to that of one studying to become a health professional. While donning the white coat is a sign of a changed role, the white coat is also a powerful symbol of transformation. White is a symbol of purity, and the white coat symbolizes the purity of purpose being affirmed in becoming a health professional. Dentistry is afforded the status of a learned profession as a result of the power dentists possess over patients seeking care; this power is based in sophisticated knowledge. Patients must trust that the dentist's knowledge and skills will be used in their best interest-always to benefit, never to exploit. The white coat symbolizes an affirmation on the part of aspiring dentists that their purpose will be pure and that they can be trusted to honor the tradition of the learned professions in placing the interest of patients above self. Absent an emphasis on the symbolic nature of the white coat ceremony, it can simply become an opportunity to publicly congratulate individuals for their success in gaining entrance to the study of dentistry. By understanding its significance, however, the white coat ceremony can serve as a powerful, meaningful ritual emphasizing the transformation occurring within an individual who is entering the profession of dentistry.

  8. White matter disease of the brain

    International Nuclear Information System (INIS)

    Melville, G.E.; Fernandez, R.E.; Kishore, P.R.S.; Lee, S.H.

    1987-01-01

    The white matter disorders that are discussed in this chapter are subdivided into those disorders within which there is breakdown of normal myelin, termed myelinoclastic, and those diseases involving either formation or maintenance of abnormal myeline, termed dysmyelinating. CT is a well-established technique for studying white matter disease. Magnetic resonance imaging (MRI) is a new noninvasive technique which has shown greater sensitivity to white matter abnormalities. However, because of the rarity of may white matter diseases coupled with limited availability of MR facilities, the MRI experience in evaluating these patients is not extensive yet. Some patients may not be suitable for MRI because of the longer period of patient immobility that is required to avoid motion artifacts

  9. White dwarf-red dwarf binaries in the Galaxy

    NARCIS (Netherlands)

    Besselaar, E.J.M. van den

    2007-01-01

    This PhD thesis shows several studies on white dwarf - red dwarf binaries. White dwarfs are the end products of most stars and red dwarfs are normal hydrogen burning low-mass stars. White dwarf - red dwarf binaries are both blue (white dwarf) and red (red dwarf). Together with the fact that they are

  10. Merging White Dwarfs and Thermonuclear Supernovae

    OpenAIRE

    van Kerkwijk, Marten H.

    2012-01-01

    Thermonuclear supernovae result when interaction with a companion reignites nuclear fusion in a carbon-oxygen white dwarf, causing a thermonuclear runaway, a catastrophic gain in pressure, and the disintegration of the whole white dwarf. It is usually thought that fusion is reignited in near-pycnonuclear conditions when the white dwarf approaches the Chandrasekhar mass. I briefly describe two long-standing problems faced by this scenario, and our suggestion that these supernovae instead resul...

  11. Histology of white pine blister rust in needles of resistant and susceptible eastern white pine

    Science.gov (United States)

    Joel A. Jurgens; Robert A. Blanchette; Paul J. Zambino; Andrew David

    2003-01-01

    White pine blister rust, Cronartium ribicola, has plagued the forests of North America for almost a century. Over past decades, eastern white pine (Pinus strobus) that appear to tolerate the disease have been selected and incorporated into breeding programs. Seeds from P. strobus with putative resistance were...

  12. Evaluation of Whiteness in Linen and Semi-linen Fabrics

    OpenAIRE

    Liucina Kot; Eglė KUMPIKAITĖ; Audronė RAGAIŠIENĖ; Žaneta RUKUIŽIENĖ

    2015-01-01

    Whiteness of textiles is one of the main "white" product quality indicators described by the following parameters: lightness of a colour, colour tone (white shade), white uniformity and stability under the influence of physical factors. “White” textile products can be perceived by comparing them with a white standard (Pantone colour palette). On the other hand, the whiteness of the fabric can be estimated using the colorimeter and determining lightness of a fabric L. The purpose of a research...

  13. NEW COOLING SEQUENCES FOR OLD WHITE DWARFS

    International Nuclear Information System (INIS)

    Renedo, I.; Althaus, L. G.; GarcIa-Berro, E.; Miller Bertolami, M. M.; Romero, A. D.; Corsico, A. H.; Rohrmann, R. D.

    2010-01-01

    We present full evolutionary calculations appropriate for the study of hydrogen-rich DA white dwarfs. This is done by evolving white dwarf progenitors from the zero-age main sequence, through the core hydrogen-burning phase, the helium-burning phase, and the thermally pulsing asymptotic giant branch phase to the white dwarf stage. Complete evolutionary sequences are computed for a wide range of stellar masses and for two different metallicities, Z = 0.01, which is representative of the solar neighborhood, and Z = 0.001, which is appropriate for the study of old stellar systems, like globular clusters. During the white dwarf cooling stage, we self-consistently compute the phase in which nuclear reactions are still important, the diffusive evolution of the elements in the outer layers and, finally, we also take into account all the relevant energy sources in the deep interior of the white dwarf, such as the release of latent heat and the release of gravitational energy due to carbon-oxygen phase separation upon crystallization. We also provide colors and magnitudes for these sequences, based on a new set of improved non-gray white dwarf model atmospheres, which include the most up-to-date physical inputs like the Lyα quasi-molecular opacity. The calculations are extended down to an effective temperature of 2500 K. Our calculations provide a homogeneous set of evolutionary cooling tracks appropriate for mass and age determinations of old DA white dwarfs and for white dwarf cosmochronology of the different Galactic populations.

  14. White House

    Science.gov (United States)

    ... content Jump to navigation the WHITE HOUSE President Donald J. Trump Get in Touch Home Briefing Room From the ... For All Americans The Administration The Administration President Donald J. Trump Vice President Mike Pence First Lady Melania Trump ...

  15. White matter involvement in sporadic Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Caverzasi, Eduardo; Mandelli, Maria Luisa; DeArmond, Stephen J; Hess, Christopher P; Vitali, Paolo; Papinutto, Nico; Oehler, Abby; Miller, Bruce L; Lobach, Irina V; Bastianello, Stefano; Geschwind, Michael D; Henry, Roland G

    2014-12-01

    Sporadic Creutzfeldt-Jakob disease is considered primarily a disease of grey matter, although the extent of white matter involvement has not been well described. We used diffusion tensor imaging to study the white matter in sporadic Creutzfeldt-Jakob disease compared to healthy control subjects and to correlated magnetic resonance imaging findings with histopathology. Twenty-six patients with sporadic Creutzfeldt-Jakob disease and nine age- and gender-matched healthy control subjects underwent volumetric T1-weighted and diffusion tensor imaging. Six patients had post-mortem brain analysis available for assessment of neuropathological findings associated with prion disease. Parcellation of the subcortical white matter was performed on 3D T1-weighted volumes using Freesurfer. Diffusion tensor imaging maps were calculated and transformed to the 3D-T1 space; the average value for each diffusion metric was calculated in the total white matter and in regional volumes of interest. Tract-based spatial statistics analysis was also performed to investigate the deeper white matter tracts. There was a significant reduction of mean (P=0.002), axial (P=0.0003) and radial (P=0.0134) diffusivities in the total white matter in sporadic Creutzfeldt-Jakob disease. Mean diffusivity was significantly lower in most white matter volumes of interest (PCreutzfeldt-Jakob disease. Mean diffusivity reduction reflected concomitant decrease of both axial and radial diffusivity, without appreciable changes in white matter anisotropy. Tract-based spatial statistics analysis showed significant reductions of mean diffusivity within the white matter of patients with sporadic Creutzfeldt-Jakob disease, mainly in the left hemisphere, with a strong trend (P=0.06) towards reduced mean diffusivity in most of the white matter bilaterally. In contrast, by visual assessment there was no white matter abnormality either on T2-weighted or diffusion-weighted images. Widespread reduction in white matter mean

  16. Digging of 'Snow White' Begins

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander began excavating a new trench, dubbed 'Snow White,' in a patch of Martian soil located near the center of a polygonal surface feature, nicknamed 'Cheshire Cat.' The trench is about 2 centimeters (.8 inches) deep and 30 centimeters (about 12 inches) long. The 'dump pile' is located at the top of the trench, the side farthest away from the lander, and has been dubbed 'Croquet Ground.' The digging site has been named 'Wonderland.' At this early stage of digging, the Phoenix team did not expect to find any of the white material seen in the first trench, now called 'Dodo-Goldilocks.' That trench showed white material at a depth of about 5 centimeters (2 inches). More digging of Snow White is planned for coming sols, or Martian days. The dark portion of this image is the shadow of the lander's solar panel; the bright areas within this region are not in shadow. Snow White was dug on Sol 22 (June 17, 2008) with Phoenix's Robotic Arm. This picture was acquired on the same day by the lander's Surface Stereo Imager. This image has been enhanced to brighten shaded areas. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  17. 78 FR 25458 - Ryan White HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV...

    Science.gov (United States)

    2013-05-01

    ... HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV/AIDS Program AGENCY: Health Resources and Services Administration (HRSA), HHS. ACTION: Notice of Ryan White HIV/AIDS... HIV/AIDS, HRSA will provide a one-time noncompetitive Ryan White HIV/AIDS Program Part C funds award...

  18. 78 FR 10183 - Ryan White HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV...

    Science.gov (United States)

    2013-02-13

    ... HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV/AIDS Program.... ACTION: Notice of Ryan White HIV/AIDS Program Part C Early Intervention Services One-Time Noncompetitive... care services for persons living with HIV/AIDS, HRSA will provide one-time noncompetitive Ryan White...

  19. 78 FR 31568 - Ryan White HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV...

    Science.gov (United States)

    2013-05-24

    ... HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV/AIDS Program.... ACTION: Notice of Ryan White HIV/AIDS Program Part C Early Intervention Services One-Time Noncompetitive... care services for persons living with HIV/AIDS, HRSA will provide a one-time noncompetitive Ryan White...

  20. Rare White dwarf stars with carbon atmospheres

    OpenAIRE

    Dufour, P.; Liebert, James; Fontaine, G.; Behara, N.

    2007-01-01

    White dwarfs represent the endpoint of stellar evolution for stars with initial masses between approximately 0.07 msun and 8-10 msun, where msun is the mass of the Sun (more massive stars end their life as either black holes or neutron stars). The theory of stellar evolution predicts that the majority of white dwarfs have a core made of carbon and oxygen, which itself is surrounded by a helium layer and, for ~80 per cent of known white dwarfs, by an additional hydrogen layer. All white dwarfs...

  1. White dwarfs in the WTS: Eclipsing binaries

    Directory of Open Access Journals (Sweden)

    Burleigh M.R.

    2013-04-01

    Full Text Available We have identified photometric white dwarf candidates in the WFCAM transit survey through a reduced proper motion versus colour approach. Box-fitting with parameters adjusted to detect the unique signature of a white dwarf + planet/brown dwarf transit/eclipse event was performed, as well as looking for variability due to the irradiation of the companions atmosphere by the white dwarf's high UV flux. We have also performed a simple sensitivity analysis in order to assess the ability of the survey to detect companions to white dwarfs via the transit method.

  2. CdSe white quantum dots-based white light-emitting diodes with high color rendering index

    Science.gov (United States)

    Su, Yu-Sheng; Hsiao, Chih-Chun; Chung, Shu-Ru

    2016-09-01

    A white light emission CdSe quantum dots (QDs) can be prepared by chemical route under 180°C. An organic oleic acid (OA) is used to react with CdO to form Cd-OA complex. Hexadecylamine (HDA) and 1-Octadecene (ODE) were used as co-surfactants. By controlling the reaction time, a white light emission CdSe QDs can be obtained after reacts for 3 to 10 min. The luminescence spectra compose two obvious emission peaks and entire visible light ranges from 400 to 650 nm. Based on TEM measurement result, spherical morphologies with particle size 2.39+/-0.27 nm can be obtained. The quantum yields (QYs) of white CdSe QD are between 20 and 60 %, which depends on reaction time. A white CdSe QDs were mixed with UV cured gel (OPAS-226) with weight ratios 50.0 wt. %, and putted the mixture into reflective cup (3020, 13 mil) as convert type. The white LEDs have controllable CIE coordinates and correlated color temperature (CCT). The luminous efficacy of the device is less than 3 lm/W, but the color rendering index (CRI) for all devices are higher than 80. Since the luminous efficacy of hybrid devices has a direct dependence on the external QY of the UV-LED as well, the luminous efficacy can be improved by well dispersion of CdSe QDs in UV gel matrix and using optimized LED chips. Therefore, in this study, we provide a new and simple method to prepare high QY of white CdSe QDs and its have a potential to applicate in solid-state lighting.

  3. Margaret Bourke-White (1904-1971)

    Science.gov (United States)

    Perry, Alyce

    2004-01-01

    This brief article describes notable events in Margaret Bourke-White's life and links these events to one of her well-known prints, "The George Washington Bridge." Margaret Bourke-White is best known for her photojournalism and commercial photography. Her photograph of the George Washington Bridge published in Fortune magazine in 1933, explores…

  4. 21 CFR 137.255 - Bolted white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted white corn meal. 137.255 Section 137.255... Flours and Related Products § 137.255 Bolted white corn meal. (a) Bolted white corn meal is the food prepared by so grinding and sifting cleaned white corn that: (1) Its crude fiber content is less than 1.2...

  5. Polarized radiation in magnetic white dwarfs

    International Nuclear Information System (INIS)

    Rosi, L.A.; Zimmerman, R.L.; Kemp, J.C.

    1976-01-01

    A model for magnetic white dwarfs is proposed which attributes the partially polarized light to synchrotron radiation. The source of the radiation is relativistic electrons trapped in the magnetosphere of a white dwarf. The white dwarf's magnetic field is assumed to be dipolar. The Stokes parameters for the synchrotron radiation are tabulated as a function of frequency, observer's orientation, and energy and spatial distribution of the relativistic electrons. The results of the synchrotron calculations are applied to the polarization observations of Grw+70degree8247 and DQ Herculis. This model can account for the major features of the polarized radiation coming from these two magnetic white dwarfs. The calculations predict for Grw+70degree8247 that the surface magnetic field is B/sub s/approximately-less-than4 x 10 6 gauss, that the incident viewing angle is 45degreeapproximately-less-thantheta 0 approximately-less-than75degree, and that the electrons are trapped with nearly an isotropic distribution about the white dwarf. For DQ Herculis the surface magnetic field is B/sub s/approximately-less-than7 x 10 6 gauss and the trapped electrons are confined to a dislike region about the white dwarf. For both cases the density of electrons in the magnetosphere falls in the range of 10 5 approximately-less-thannapproximately-less-than10 7 cm -3 with energies of about 4--35 MeV

  6. The Veil of Professionalism: An Autoethnographic Critique of White Positional Identities in the Figured Worlds of White Research Performance

    Science.gov (United States)

    Pennington, Julie L.; Prater, Kathryn

    2016-01-01

    Two white researchers critique the professional veil of silence they created as they reflected on a qualitative study they performed 12 years earlier. Autoethnography and performance ethnography are utilized to examine the ways in which whiteness can remain unexamined throughout the research process due to the construction of white positional…

  7. White pine blister rust resistance of 12 western white pine families at three field sites in the Pacific Northwest

    Science.gov (United States)

    Richard A. Sniezko; Robert Danchok; Jim Hamlin; Angelia Kegley; Sally Long; James Mayo

    2012-01-01

    Western white pine (Pinus monticola Douglas ex D. Don) is highly susceptible to the non-native, invasive pathogen Cronartium ribicola, the causative agent of white pine blister rust. The susceptibility of western white pine to blister rust has limited its use in restoration and reforestation throughout much of western North...

  8. Tough or Tender: (Dis)Similarities in White College Students' Perceptions of Black and White Women

    Science.gov (United States)

    Donovan, Roxanne A.

    2011-01-01

    Although intersectional theory and empirical evidence suggest that race impacts how women are perceived, there is a dearth of research on how the dominant culture stereotypes Black women compared to White women. The current study addresses this gap using an intersectional framework to investigate White college students' stereotypes of Black and…

  9. 21 CFR 160.150 - Frozen egg whites.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by freezing...

  10. Vertical migrations of a deep-sea fish and its prey.

    Directory of Open Access Journals (Sweden)

    Pedro Afonso

    Full Text Available It has been speculated that some deep-sea fishes can display large vertical migrations and likely doing so to explore the full suite of benthopelagic food resources, especially the pelagic organisms of the deep scattering layer (DSL. This would help explain the success of fishes residing at seamounts and the increased biodiversity found in these features of the open ocean. We combined active plus passive acoustic telemetry of blackspot seabream with in situ environmental and biological (backscattering data collection at a seamount to verify if its behaviour is dominated by vertical movements as a response to temporal changes in environmental conditions and pelagic prey availability. We found that seabream extensively migrate up and down the water column, that these patterns are cyclic both in short-term (tidal, diel as well as long-term (seasonal scales, and that they partially match the availability of potential DSL prey components. Furthermore, the emerging pattern points to a more complex spatial behaviour than previously anticipated, suggesting a seasonal switch in the diel behaviour mode (benthic vs. pelagic of seabream, which may reflect an adaptation to differences in prey availability. This study is the first to document the fine scale three-dimensional behaviour of a deep-sea fish residing at seamounts.

  11. White Sturgeon Bibliography, 1985 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Fickeisen, Duane H. (Pacific Northwest National Laboratory, Richland, WA)

    1986-03-01

    This bibliography presents citations to the majority of published materials on white sturgeon (Acipenser transmontanus). The purpose was to assist in planning and implementing research on white sturgeon in the Columbia River system. (ACR)

  12. The antiplaque efficacy of white tea extract mouthrinse

    Directory of Open Access Journals (Sweden)

    Dipika Kalyan Mitra

    2016-01-01

    Full Text Available Objective: This study was conducted to assess the antiplaque efficacy of a mouthwash containing white tea. It also assessed the antibacterial properties of white tea against Prevotella intermedia (Pi, Porphyromonas gingivalis (Pg, and Aggregatibacter actinomycetemcomitans (Aa in vitro. Materials and Methods: Forty-five subjects with healthy periodontium were randomly chosen and were divided into three groups and advised to use mouthwashes A, B, and C (Group A, white tea; Group B, distilled water [placebo]; Group C, chlorhexidine for 4 days. They were advised to refrain from any kind of mechanical oral hygiene techniques. Plaque index (PI was checked on day 1 and 5. In vitro testing for against Pi, Pg, and Aa against white tea extract was undertaken. Results: PI significantly increased from day 1 to day 5 (P < 0.01 in Groups A, B, and C. In inter-group comparison, there was a statistical significant difference between white tea mouthrinse group and placebo group, chlorhexidine group and placebo group and also chlorhexidine group and white tea mouthrinse group. However, chlohexidine showed superior antiplaque activity. In vitro test, white tea showed effective inhibition against all three bacterial strains Pi, Pg, and Aa at 1% concentration. Conclusion: White tea mouthrinse potently inhibits plaque formation although not as comparable to chlorhexidine mouthrinse. Hence, for those preferring herbal products, white tea mouthrinse is a good option.

  13. 78 FR 78976 - Ryan White HIV/AIDS Program Part C Early Intervention Services Grant Under the Ryan White HIV...

    Science.gov (United States)

    2013-12-27

    ... HIV/AIDS Program Part C Early Intervention Services Grant Under the Ryan White HIV/AIDS Program AGENCY...: Notice of Ryan White HIV/AIDS Program Part C Early Intervention Services One-Time Noncompetitive Award To... services for persons living with HIV/AIDS, HRSA will provide a one-time noncompetitive Ryan White HIV/AIDS...

  14. Effects of temperature and salinity on resting metabolism in two ...

    African Journals Online (AJOL)

    This study investigates the resting metabolic rate (RMR; mg O2 g/h) of the resident rock pool fish Caffrogobius caffer and the transient sparid Diplodus sargus capensis at a range of salinities (5, 15, 25, 35 and 45 PSU) and temperatures (14, 20 and 28°C) using closed-vessel respirometry. Both species were temperature ...

  15. Evaluation of Whiteness in Linen and Semi-linen Fabrics

    Directory of Open Access Journals (Sweden)

    Liucina Kot

    2015-03-01

    Full Text Available Whiteness of textiles is one of the main "white" product quality indicators described by the following parameters: lightness of a colour, colour tone (white shade, white uniformity and stability under the influence of physical factors. “White” textile products can be perceived by comparing them with a white standard (Pantone colour palette. On the other hand, the whiteness of the fabric can be estimated using the colorimeter and determining lightness of a fabric L. The purpose of a research is to assess the whiteness of a linen and semi-linen fabric using two different methods, to carry out a comparative analysis of the results and to associate fabric whiteness with the fabric structure parameters. Two methods were used for experiment (colorimeter Spectraflash SF450X and expert assessment of whiteness. The analysed colours of a fabric were divided into five colours: white, whitish, light grey, grey and dark grey. The examination of the two methods, different results were obtained: testing with colorimeter, white colour was found in only one fabric, while the experts found the fabrics of white colour much more. The opinions of experts vary also. Fabric lightness L was associated with fabric structure parameters – the warp and weft settings and fabric weave. It was found that these fabric structure parameters affect the lightness of a colour of a fabric L very little.DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5348

  16. ZnO-nanorods: A possible white LED phosphor

    Science.gov (United States)

    Sarangi, Sachindra Nath; T., Arun; Ray, Dinseh K.; Sahoo, Pratap Kumar; Nozaki, Shinji; Sugiyama, Noriyuki; Uchida, Kazuo

    2017-05-01

    The white light-emitting diodes (LEDs) have drawn much attention to replace conventional lighting sources because of low energy consumption, high light efficiency and long lifetime. Although the most common approach to produce white light is to combine a blue LED chip and a yellow phosphor, such a white LED cannot be used for a general lighting application, which requires a broad luminescence spectrum in the visible wavelength range. We have successfully chemically synthesized the ZnO nanorods showing intense broad luminescence in the visible wavelength range and made a white LED using the ZnO nanorods as phosphor excited with a blue LED. Their lengths and diameters were 2 - 10 μm and 200 - 800 nm, respectively. The wurtzite structure was confirmed by the x-ray diffraction measurement. The PL spectrum obtained by exciting the ZnO nanorods with the He-Cd laser has two peaks, one associated with the near band-edge recombination and the other with recombination via defects. The peak intensity of the near band-edge luminescence at 388 nm is much weaker than that of the defect-related luminescence. The latter luminescence peak ranges from 450 to 850 nm and broad enough to be used as a phosphor for a white LED. A white LED has been fabricated using a blue LED with 450 nm emission and ZnO nanorod powders. The LED performances show a white light emission and the electroluminescence measurement shows a stiff increase in white light intensity with increasing blue LED current. The Commission International de1'Eclairage (CIE) chromaticity colour coordinates of 450 nm LED pumped white emission shows a coordinate of (0.31, 0.32) for white LED at 350 mA. These results indicate that ZnO nanorods provides an alternate and effective approach to achieve high-performance white LEDs and also other optoelectronic devices.

  17. Explosive helium burning in white dwarf stars

    Energy Technology Data Exchange (ETDEWEB)

    Khokhlov, A.M. (AN SSSR, Moscow. Astronomicheskij Sovet)

    1984-04-01

    Helium burning kinetics in white dwarfs has been considered at constant temperatures T >= 10/sup 9/ K and densities rho >10/sup 5/ g/cm/sup 3/. It is found, that helium detonation in white dwarfs does not lead to formation of light (A < 56) elements. Thus, helium white dwarf model for supernova 1 is inconsistent with observations.

  18. White noise excitation in a hot plasma

    International Nuclear Information System (INIS)

    Ito, Masataka

    1977-01-01

    In a low frequency range, a property of white noise in a hot plasma is studied experimentally. A frequency component of white noise is observed to propagate with a phase velocity which is equal to the ion accoustic wave velocity. The white noise, which is launched in a plasma, is considered as the sum of ion acoustic waves. (auth.)

  19. White-black and white-Hispanic differences on fluid and crystallized abilities by age across the 11- to 94-year range.

    Science.gov (United States)

    Kaufman, J C; McLean, J E; Kaufman, A S; Kaufman, N L

    1994-12-01

    Standardization data for the Kaufman Adolescent and Adult Intelligence Test (KAIT) were used to examine white-black and white-Hispanic differences on the Horn-Cattell crystallized and fluid constructs at several age groups across the broad 11- to 94-year span. Samples included 1,547 white, 241 black, and 140 Hispanic persons. Multivariate analyses with educational attainment covaried yielded only one significant finding: the white-black difference on the Crystallized Famous Faces subtest became smaller with increasing age.

  20. The WFCAM transit survey and cool white dwarfs

    Directory of Open Access Journals (Sweden)

    Pinfield D.

    2013-04-01

    Full Text Available We present results from our search for cool white dwarfs in the WTS (WFCAM Transit Survey. Repeat observations starting in 2007 allowed to produce deep stacked images in J and measure proper motions. We combine this with deep optical imaging to select cool white dwarf candidates (Teff < 5000 K. About 27 cool white dwarf candidates with proper motions above 0.10 arcsec/yr were identified in one of the fields representing 1/8th of the survey area. Follow-up spectroscopy with the 10.2 m GTC telescope at La Palma confirmed the white dwarf status for all observed candidates. On-going work is being carried out to increase the sample of cool white dwarfs that will allow a more comprehensive study of the thick disk/halo white dwarf population.

  1. Effects of magnetic fields in white dwarfs

    International Nuclear Information System (INIS)

    Franzon, Bruno; Schramm, Stefan

    2017-01-01

    We perform calculations of white dwarfs endowed with strong magnetic fields. White dwarfs are the progenitors of supernova Type Ia explosions and they are widely used as candles to show that the Universe is expanding and accelerating. However, observations of ultraluminous supernovae have suggested that the progenitor of such an explosion should be a white dwarf with mass above the well-known Chandrasekhar limit ∼ 1.4 M⊙. In corroboration with other works, but by using a fully general relativistic framework, we obtained also strongly magnetized white dwarfs with masses M ∼ 2.0 M⊙. (paper)

  2. Axion cooling of white dwarfs

    OpenAIRE

    Isern, J.; Catalan, S.; Garcia--Berro, E.; Salaris, M.; Torres, S.

    2013-01-01

    The evolution of white dwarfs is a simple gravothermal process. This process can be tested in two ways, through the luminosity function of these stars and through the secular variation of the period of pulsation of those stars that are variable. Here we show how the mass of the axion can be constrained using the white dwarf luminosity function.

  3. What fraction of white dwarfs are members of binary systems?

    International Nuclear Information System (INIS)

    Holberg, J B

    2009-01-01

    White dwarfs were originally discovered as the subordinate faint companions of bright nearby stars (i.e. Sirius B and 40 Eri B). Several general categories of binary systems involving white dwarfs are recognized: Sirius-like systems, where the white dwarf may be difficult to detect, binary systems containing white dwarfs and low mass stars, where the white dwarf is often readily discerned; and double degenerate systems. Different modes of white dwarf discovery influence our perception of both the overall binary fraction and the nature of these systems; proper motion surveys emphasize resolved systems, while photometric surveys emphasize unresolved systems containing relatively hot white dwarfs. Recent studies of the local white dwarf population offer some hope of achieving realistic estimates of the relative number of binary systems containing white dwarfs. A sample of 132 white dwarfs within 20 pc indicates that an individual white dwarf has a probability of 32 ± 8% of occurring within a binary or multiple star system.

  4. Whiteness as Cursed Property: An Interdisciplinary Intervention with Joyce Carol Oates’s Bellefleur and Cheryl Harris’s “Whiteness as Property”

    Directory of Open Access Journals (Sweden)

    Karen Gaffney

    2015-02-01

    Full Text Available This article begins with the assertion that now more than ever, in the aftermath of Ferguson and in a time when many believe our society to be post-racial, we need to bring together scholars and activists who care about racial justice, regardless of discipline, and build interdisciplinary tools for fighting racism. Furthermore, we need to understand and reveal how whiteness has been socially constructed because the power of whiteness lies in its invisibility, and that fuels the perpetuation of systemic racism. In making whiteness visible, we can see how it has been wielded as a weapon, which in turn will allow us to see how destructive it is for everyone, whites included. As part of this work, we need to break down the disciplinary boundary between literary studies and critical race theory (a field within legal studies that examines systemic racism in the context of the law. One example of such an interdisciplinary intervention is to bring together Cheryl Harris, a critical race theorist, and Joyce Carol Oates, a novelist. Harris published one of the foundational pieces of critical race theory in 1993 with her law review article “Whiteness as Property,” a legal analysis of whiteness, and Oates produced a masterpiece of American literature in 1980 with her novel Bellefleur, a complex story of a powerful white family that spans seven generations. This pairing lays the groundwork for the type of interdisciplinary dialogue we need because, within literary studies, when the novelist is white and the characters are white, there is still very little emphasis on the study of whiteness even though race is a significant focus of attention when the novelist and characters are people of color. Whiteness is still invisible, and that is part of the problem I am describing, both within literary studies and in our society at large. We need an interdisciplinary intervention to pull back the curtain on whiteness, see how it operates, recognize its danger, and

  5. Immigration concern and the white/non-white difference in smoking: Group position theory and health.

    Science.gov (United States)

    Samson, Frank L

    2017-12-01

    National data indicate that U.S. whites have a higher prevalence of smoking compared to non-whites. Group position theory and public opinion data suggest racial differences in immigration concern. This study examines whether immigration concern mediates the racial difference in smoking. Drawing on the 2012 General Social Survey, the 2012 American National Election Study, and the 2006 Portraits of American Life Study, immigration concern was associated with smoking, controlling for covariates across all three nationally representative surveys. Mediation analysis indicated that immigration concern partially mediated the higher odds of smoking among whites across all surveys. Immigration concern also presents a possible explanation for the healthy immigrant advantage and Hispanic paradox as they pertain to smoking differences.

  6. White matter alterations in neurodegenerative and vascular dementia

    International Nuclear Information System (INIS)

    Supprian, T.; Kessler, H.; Falkai, P.; Retz, W.; Roesler, M.; Grunwald, I.; Reith, W.

    2003-01-01

    Due to a significant overlap of the two syndromes, differentiation of degenerative dementia of the Alzheimer-type from vascular dementia may be difficult even when imaging studies are available. White matter changes occur in many patients suffering from Alzheimer's disease. Little is known about the impact of white matter changes on the course and clinical presentation of Alzheimer's disease. High sensitivity of MRI in the detection of white matter alterations may account for over-diagnosing vascular dementia. The clinical significance of white matter alterations in dementia is still a matter of debate. The article reviews current concepts about the role of white matter alterations in dementia. (orig.) [de

  7. Nucleosynthesis in cold white dwarf explosions

    International Nuclear Information System (INIS)

    Canal, R.; Hernanz, M.

    1986-01-01

    Type I supernovae (SNI) are generally thought to be the main contributors to the galactic nucleosynthesis of iron-peak elements and their yields of intermediate-mass elements may also be important. We concentrate here upon a different class of models, based on the explosion of cold, massive, partially solid white dwarfs. We show that such white dwarfs must be relatively frequent among SNI progenitors and how their hydrodynamics upon ignition is very different from that of hotter, fluid white dwarfs. The implications for nucleosynthesis are briefly discussed and some preliminary results are presented

  8. White Paranoia

    DEFF Research Database (Denmark)

    Jørholt, Eva

    2017-01-01

    Inspired by Alain Robbe-Grillet’s novel La Jalousie (1957), the essay contends that Michael Haneke’s Caché (2005) takes its viewers inside a postcolonial white paranoia which is, arguably, the root cause of the exclusion, segregation and racist discrimination that many immigrants from the former ...

  9. White matter abnormalities in tuberous sclerosis complex

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, P.D. [Sheffield Univ. (United Kingdom). Academic Dept. of Radiology; Bolton, P. [Cambridge Univ. (United Kingdom). Section of Developmental Psychiatry; Verity, C. [Addenbrooke`s NHS Trust, Cambridge (United Kingdom). Dept. of Paediatric Radiology

    1998-09-01

    The aim of this study was to investigate and describe the range of white matter abnormalities in children with tuberous sclerosis complex by means of MR imaging. Material and Methods: A retrospective cross-sectional study was performed on the basis of MR imaging findings in 20 cases of tuberous sclerosis complex in children aged 17 years or younger. Results: White matter abnormalities were present in 19/20 (95%) cases of tuberous sclerosis complex. These were most frequently (19/20 cases) found in relation to cortical tubers in the supratentorial compartment. White matter abnormalities related to tubers were found in the cerebellum in 3/20 (15%) cases. White matter abnormalities described as radial migration lines were found in relation to 5 tubers in 3 (15%) children. In 4/20 (20%) cases, white matter abnormalities were found that were not related to cortical tubers. These areas had the appearance of white matter cysts in 3 cases and infarction in the fourth. In the latter case there was a definable event in the clinical history, supporting the diagnosis of stroke. Conclusion: A range of white matter abnormalities were found by MR imaging in tuberous sclerosis complex, the commonest being gliosis and hypomyelination related to cortical tubers. Radial migration lines were seen infrequently in relation to cortical tubers and these are thought to represent heterotopic glia and neurons along the expected path of cortical migration. (orig.)

  10. A possible magnetic DA white dwarf

    International Nuclear Information System (INIS)

    Wickramasinghe, D.T.; Bessell, M.S.

    1976-01-01

    The spectrum of a peculiar southern white dwarf suspect BPM 25114 is described. A possible magnetic interpretation suggests a DA white dwarf with a field of about 10 7 gauss. The star appears to be both a spectrum variable and perhaps light variable

  11. Black and white human skin differences

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Maibach, H I

    1979-01-01

    This review of black and white human skin differences emphasizes the alleged importance of factors other than the obvious, i.e., skin color. Physicochemical differences and differences in susceptibility to irritants and allergens suggest a more resistant black than white skin. Differences appear...

  12. Optical appearance of white holes

    International Nuclear Information System (INIS)

    Lake, K.; Roeder, R.C.

    1978-01-01

    The detailed optical properties of white holes are examined within the framework of geometrical optics. It is shown that the appearance of the objects most likely to be observed at late times is in fact determined by their early histories. These ccalculations indicate that one cannot invoke the simple concept of a stable white hole as a ''natural'' explanation of highly energetic astrophysical phenomena

  13. European Whiteness?

    DEFF Research Database (Denmark)

    Blaagaard, Bolette

    2008-01-01

    Born out of the United States’ (U.S.) history of slavery and segregation and intertwined with gender studies and feminism, the field of critical whiteness studies does not fit easily into a European setting and the particular historical context that entails. In order for a field of European...

  14. White dwarf stars with carbon atmospheres.

    Science.gov (United States)

    Dufour, P; Liebert, J; Fontaine, G; Behara, N

    2007-11-22

    White dwarfs represent the endpoint of stellar evolution for stars with initial masses between approximately 0.07 and 8-10, where is the mass of the Sun (more massive stars end their life as either black holes or neutron stars). The theory of stellar evolution predicts that the majority of white dwarfs have a core made of carbon and oxygen, which itself is surrounded by a helium layer and, for approximately 80 per cent of known white dwarfs, by an additional hydrogen layer. All white dwarfs therefore have been traditionally found to belong to one of two categories: those with a hydrogen-rich atmosphere (the DA spectral type) and those with a helium-rich atmosphere (the non-DAs). Here we report the discovery of several white dwarfs with atmospheres primarily composed of carbon, with little or no trace of hydrogen or helium. Our analysis shows that the atmospheric parameters found for these stars do not fit satisfactorily in any of the currently known theories of post-asymptotic giant branch evolution, although these objects might be the cooler counterpart of the unique and extensively studied PG 1159 star H1504+65 (refs 4-7). These stars, together with H1504+65, might accordingly form a new evolutionary sequence that follows the asymptotic giant branch.

  15. White dwarf models of supernovae and cataclysmic variables

    International Nuclear Information System (INIS)

    Nomoto, K.; Hashimoto, M.

    1986-01-01

    If the accreting white dwarf increases its mass to the Chandrasekhar mass, it will either explode as a Type I supernova or collapse to form a neutron star. In fact, there is a good agreement between the exploding white dwarf model for Type I supernovae and observations. We describe various types of evolution of accreting white dwarfs as a function of binary parameters (i.e,. composition, mass, and age of the white dwarf, its companion star, and mass accretion rate), and discuss the conditions for the precursors of exploding or collapsing white dwarfs, and their relevance to cataclysmic variables. Particular attention is given to helium star cataclysmics which might be the precursors of some Type I supernovae or ultrashort period x-ray binaries. Finally we present new evolutionary calculations using the updated nuclear reaction rates for the formation of O+Ne+Mg white dwarfs, and discuss the composition structure and their relevance to the model for neon novae. 61 refs., 14 figs

  16. A COLOR THAT COMMUNICATES WITHOUT A WORD – "WHITE"

    OpenAIRE

    Shivani Sharma; Vandana Bharti

    2017-01-01

    The meaning of color white is purity, innocence, wholeness and completeness. It is the color produced by the combination of all the colors of visible spectrum.The color white belongs to ancient history. During the Paleolithic age, the artists used calcite and in chalk in their paintings. Egyptians connected it with their goddess Isis,who only dressed in white linen and hence used to wrap mummies.White was often associated with mother’s milk, in Greek mythology .White is the color of the human...

  17. 21 CFR 137.270 - Self-rising white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising white corn meal. 137.270 Section 137... Cereal Flours and Related Products § 137.270 Self-rising white corn meal. (a) Self-rising white corn meal is an intimate mixture of white corn meal, sodium bicarbonate, and one or both of the acid-reacting...

  18. The Challenge of White Dialectics: Making the "Invisible" Visible

    Science.gov (United States)

    Sue, Derald Wing

    2011-01-01

    In this article, the author comments on the substance of Todd and Abrams's study on "White Dialectics: A New Framework for Theory, Research, and Practice With White Students" (2011). The study is a major contribution to the importance of raising awareness of how Whiteness, White privilege, and one's own complicity in the perpetuation of racism are…

  19. Light Sterile Neutrinos: A White Paper

    DEFF Research Database (Denmark)

    Abazajian, K. N.; Acero, M. A.; Agarwalla, S. K.

    2012-01-01

    This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data.......This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data....

  20. Spaceflight Effect on White Matter Structural Integrity

    Science.gov (United States)

    Lee, Jessica K.; Kopplemans, Vincent; Paternack, Ofer; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

    2017-01-01

    Recent reports of elevated brain white matter hyperintensity (WMH) counts and volume in postflight astronaut MRIs suggest that further examination of spaceflight's impact on the microstructure of brain white matter is warranted. To this end, retrospective longitudinal diffusion-weighted MRI scans obtained from 15 astronauts were evaluated. In light of the recent reports of microgravity-induced cephalad fluid shift and gray matter atrophy seen in astronauts, we applied a technique to estimate diffusion tensor imaging (DTI) metrics corrected for free water contamination. This approach enabled the analysis of white matter tissue-specific alterations that are unrelated to fluid shifts, occurring from before spaceflight to after landing. After spaceflight, decreased fractional anisotropy (FA) values were detected in an area encompassing the superior and inferior longitudinal fasciculi and the inferior fronto-occipital fasciculus. Increased radial diffusivity (RD) and decreased axial diffusivity (AD) were also detected within overlapping regions. In addition, FA values in the corticospinal tract decreased and RD measures in the precentral gyrus white matter increased from before to after flight. The results show disrupted structural connectivity of white matter in tracts involved in visuospatial processing, vestibular function, and movement control as a result of spaceflight. The findings may help us understand the structural underpinnings of the extensive spaceflight-induced sensorimotor remodeling. Prospective longitudinal assessment of the white matter integrity in astronauts is needed to characterize the evolution of white matter microstructural changes associated with spaceflight, their behavioral consequences, and the time course of recovery. Supported by a grant from the National Space Biomedical Research Institute, NASA NCC 9-58.

  1. White dwarfs in cataclysmic variables

    International Nuclear Information System (INIS)

    Sion, E.M.

    1987-01-01

    The physical properties and evolutionary state of the underlying white dwarfs in CVs are explored. Observations of 25 white dwarfs with effective temperature upper limits of 9000-75,000 K are discussed. Correlations between effective temperature, orbital period, accretion rate, and CV type with respect to the CV period gap are considered. Quasi-static and hydrodynamic evolutionary models are used to explain the surface temperature/luminosity distribution ratios. 42 references

  2. White Free Speech: The Fraser Event and its Enlightenment Legacies

    Directory of Open Access Journals (Sweden)

    Goldie Osuri

    2011-04-01

    Full Text Available This essay discusses the 2005 Australia-wide controversy about the white supremacist comments made by Macquarie University academic Associate Professor Andrew Fraser. It locates the means by which this white supremacism manifested itself not only through Fraser comments, but also through arguments surrounding free speech/academic freedom. Using whiteness theory and its examination of whiteness as an Enlightenment legacy, Osuri argues that the collusion between Fraser’s white supremacism and the free speech/academic freedom argument is based on a disavowal of how whiteness operates, as Aileen Moreton-Robinson describes it, as an epistemological and ontological a priori, an embodied form of knowledge-production, and collective white hegemony.

  3. White dwarf evolution - Cradle-to-grave constraints via pulsation

    Science.gov (United States)

    Kawaler, Steven D.

    1990-01-01

    White dwarf evolution, particularly in the early phases, is not very strongly constrained by observation. Fortunately, white dwarfs undergo nonradial pulsation in three distinct regions of the H-R diagram. These pulsations provide accurate masses, surface compositional structure and rotation velocities, and help constrain other important physical properties. We demonstrate the application of the tools of stellar seismology to white dwarf evolution using the hot white dwarf star PG 1159-035 and the cool DAV (or ZZ Ceti) stars as examples. From pulsation studies, significant challenges to the theory of white dwarf evolution emerge.

  4. White Awareness: The Frontier of Racism Awareness Training

    Science.gov (United States)

    Katz, Judy H.; Ivey, Allen

    1977-01-01

    This article's purpose is to make white professional helpers aware of how racism undermines the helping field and to demonstrate how racism affects white people. A systematic training program for white people that develops an awareness of the masking effect of racism and develops interventions for changes is presented. (Author)

  5. Tuning the color point of a white LED

    NARCIS (Netherlands)

    Adhikary, Manashee; Meretska, Maryna; Ladovrechis, K.; Fokkema, Wouter K.; Vissenberg, Gilles; Lagendijk, Ad; Ijzerman, W.L.; Vos, Willem L.

    2018-01-01

    White light is conveniently characterized by a color point that is represented on the color space. Color point of white LED is fixed by the design parameters (e.g. Phosphor type and concentration). When the design parameters are chosen, the color point of the white LED cannot be changed. Here, we

  6. A genomewide catalogue of single nucleotide polymorphisms in white-beaked and Atlantic white-sided dolphins

    DEFF Research Database (Denmark)

    Fernández, R.; Schubert, M.; Vargas-Velázquez, A. M.

    2015-01-01

    The field of population genetics is rapidly moving into population genomics as the quantity of data generated by high-throughput sequencing platforms increases. In this study, we used restriction-site-associated DNA sequencing (RADSeq) to recover genomewide genotypes from 70 white-beaked (Lagenor......The field of population genetics is rapidly moving into population genomics as the quantity of data generated by high-throughput sequencing platforms increases. In this study, we used restriction-site-associated DNA sequencing (RADSeq) to recover genomewide genotypes from 70 white...... of genetic clusters among our sample set, we obtained an estimate of two to four clusters, corresponding to both species and possibly, two further clusters within each species. A higher diversity and lower population structuring was encountered in white-sided dolphins from the north-east Atlantic, in line...

  7. A Pilot Examination of Differences in College Adjustment Stressors and Depression and Anxiety Symptoms between White, Hispanic and White, Non-Hispanic Female College Students

    Science.gov (United States)

    Holliday, Ryan; Anderson, Elizabeth; Williams, Rush; Bird, Jessica; Matlock, Alyse; Ali, Sania; Edmondson, Christine; Morris, E. Ellen; Mullen, Kacy; Surís, Alina

    2016-01-01

    Differences in four adjustment stressors (family, interpersonal, career, and academic), and depression and anxiety symptoms were examined between White, non-Hispanic and White, Hispanic undergraduate college female students. White, Hispanic female college students reported significantly greater academic and family adjustment stressors than White,…

  8. PIXE analysis of Chinese ancient greenish white porcelain

    International Nuclear Information System (INIS)

    Cheng Lin; Ding Xunliang; Feng Songlin; Cheng Huangsheng; Zhang WenJiang; Fan Changsheng

    2006-01-01

    This paper reports the results about the PIXE analysis of major, minor and trace elements of Chinese ancient greenish white porcelain and blue-and-white porcelain produced in Hutian Kiln (Jingdezhen district, Jiangxi province) during 10th-14th centuries. The porcelain body and greenish white glaze from northern Song (AD 960), southern Song (AD 1037-1276), early Yuan (AD 1279-1320), later Yuan (AD 1320-1368) were investigated together with white-and-blue glaze from Ming dynasty (AD 1368-1644). The obtained data were further analyzed by factor analysis

  9. PIXE analysis of Chinese ancient greenish white porcelain

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Lin [Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China)]. E-mail: chenglinbnu@hotmail.com; Ding Xunliang [Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Feng Songlin [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Cheng Huangsheng [Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Zhang WenJiang [Jiangxi Provincial Institute of Cultural Relics and Archaeology, Nanchang 330008 (China); Fan Changsheng [Jiangxi Provincial Institute of Cultural Relics and Archaeology, Nanchang 330008 (China)

    2006-03-15

    This paper reports the results about the PIXE analysis of major, minor and trace elements of Chinese ancient greenish white porcelain and blue-and-white porcelain produced in Hutian Kiln (Jingdezhen district, Jiangxi province) during 10th-14th centuries. The porcelain body and greenish white glaze from northern Song (AD 960), southern Song (AD 1037-1276), early Yuan (AD 1279-1320), later Yuan (AD 1320-1368) were investigated together with white-and-blue glaze from Ming dynasty (AD 1368-1644). The obtained data were further analyzed by factor analysis.

  10. PIXE analysis of Chinese ancient greenish white porcelain

    Science.gov (United States)

    Cheng, Lin; Ding, Xun-liang; Feng, Song-lin; Cheng, Huang-sheng; Zhang, Wen-Jiang; Fan, Chang-Sheng

    2006-03-01

    This paper reports the results about the PIXE analysis of major, minor and trace elements of Chinese ancient greenish white porcelain and blue-and-white porcelain produced in Hutian Kiln (Jingdezhen district, Jiangxi province) during 10th-14th centuries. The porcelain body and greenish white glaze from northern Song (AD 960), southern Song (AD 1037-1276), early Yuan (AD 1279-1320), later Yuan (AD 1320-1368) were investigated together with white-and-blue glaze from Ming dynasty (AD 1368-1644). The obtained data were further analyzed by factor analysis.

  11. Status of white pine blister rust and seed collections in california's high-elevation white pine species

    Science.gov (United States)

    J. Dunlap

    2011-01-01

    White pine blister rust (caused by the non-native pathogen Cronartium ribicola) reached northern California about 80 years ago. Over the years its spread southward had been primarily recorded on sugar pine. However, observations on its occurrence had also been reported in several of the higher elevation five-needled white pine species in California. Since the late...

  12. White matter cysts in patients with tuberous sclerosis

    International Nuclear Information System (INIS)

    Marti-Bonmati, L.; Dosda, R.; Menor, F.; Arana, E.; Poyatos, C.

    1999-01-01

    The presence of cysts in the white matter of the central nervous system of patients with tuberous sclerosis (TS) is an uncommon finding that has been reported only recently in neuroimaging studies. This article assesses the prevalence of these lesions in a large series of patients studied by magnetic resonance imaging (MRI) and their relationship to other epidemiological and imaging findings. MRI studies were performed in 46 patients (23 males and 23 females) with a mean age of 12.7 years, and the results were examined retrospectively in the search for cortical tubers, subependymal nodules and white matter nodules, lines and cysts. Nine patients (19.6%) presented cysts in white matter. Seven had only one cyst and the remaining two patients each had two. Multiple regression analysis relating the presence of the cysts with other neuroimaging findings in these patients revealed a statistically significant relationship only with white matter nodules (odds ratio: 7.5; p=0.006). White matter cysts are small, supratentorial lesions of deep location. There is a statistically relationship between the presence of these cysts and that of nodular lesions in the white matter. This finding supports the theory that the cyst originate from white matter nodules. (Author) 17 refs

  13. A DARK SPOT ON A MASSIVE WHITE DWARF

    Energy Technology Data Exchange (ETDEWEB)

    Kilic, Mukremin; Gianninas, Alexandros; Curd, Brandon; Wisniewski, John P. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Bell, Keaton J.; Winget, D. E.; Winget, K. I. [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Brown, Warren R. [Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA 02138 (United States); Hermes, J. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Dufour, Patrick [Institut de recherche sur les exoplanétes (iREx), Département de Physique, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, QC H3C 3J7 (Canada)

    2015-12-01

    We present the serendipitous discovery of eclipse-like events around the massive white dwarf SDSS J152934.98+292801.9 (hereafter J1529+2928). We selected J1529+2928 for time-series photometry based on its spectroscopic temperature and surface gravity, which place it near the ZZ Ceti instability strip. Instead of pulsations, we detect photometric dips from this white dwarf every 38 minutes. Follow-up optical spectroscopy observations with Gemini reveal no significant radial velocity variations, ruling out stellar and brown dwarf companions. A disintegrating planet around this white dwarf cannot explain the observed light curves in different filters. Given the short period, the source of the photometric dips must be a dark spot that comes into view every 38 minutes due to the rotation of the white dwarf. Our optical spectroscopy does not show any evidence of Zeeman splitting of the Balmer lines, limiting the magnetic field strength to B < 70 kG. Since up to 15% of white dwarfs display kG magnetic fields, such eclipse-like events should be common around white dwarfs. We discuss the potential implications of this discovery on transient surveys targeting white dwarfs, like the K2 mission and the Large Synoptic Survey Telescope.

  14. White on black: can white parents teach black adoptive children how to understand and cope with racism?

    Science.gov (United States)

    Smith, Darron T; Juarez, Brenda G; Jacobson, Cardell K

    2011-01-01

    In this article, the authors examine White parents’ endeavors toward the racial enculturation and inculcation of their transracially adopted Black children. Drawing on in-depth interviews, the authors identify and analyze themes across the specific race socialization strategies and practices White adoptive parents used to help their adopted Black children to develop a positive racial identity and learn how to effectively cope with issues of race and racism. The central aim of this article is to examine how these lessons about race help to connect family members to U.S. society’s existing racial hierarchy and how these associations position individuals to help perpetuate or challenge the deeply embedded and historical structures of White supremacy. The authors use the notion of White racial framing to move outside of the traditional arguments for or against transracial adoption to instead explore how a close analysis of the adoptive parents’ racial instructions may serve as a learning tool to foster more democratic and inclusive forms of family and community.

  15. Black and White Women Managers: Access to Opportunity

    Science.gov (United States)

    Hite, Linda M.

    2004-01-01

    This study explores the differing views of Black and White female managers regarding access to key career opportunities for White women and women of color. Items addressed include access to hiring, promotions, key assignments, salary increases, acknowledgment for work, and mentors. Access to each is described by comparing White women and women of…

  16. BIOMODIFICATION OF KENAF USING WHITE ROT FUNGI

    OpenAIRE

    Rasmina Halis,; Hui Rus Tan,; Zaidon Ashaari,; Rozi Mohamed

    2012-01-01

    White rot fungi can be used as a pretreatment of biomass to degrade lignin. It also alters the structure of the lignocellulosic matter, thus increasing its accessibility to enzymes able to convert polysaccharides into simple sugars. This study compares the ability of two species of white rot fungi, Pycnoporous sanguineus and Oxyporus latemarginatus FRIM 31, to degrade lignin in kenaf chips. The white rot fungi were originally isolated from the tropical forest in Malaysia. Kenaf chips were fir...

  17. White Flame Energy switches to backhoes

    Energy Technology Data Exchange (ETDEWEB)

    Fiscor, S.

    2005-06-01

    The mountaintop coal operator, White Flame Energy has switched to different truck-shovel arrangement. Along with many surface mining operations throughout central Appalachia, the company is using hoe-configured hydraulic excavators as opposed to the traditional front-shovel arrangements. Located in Varney, WV, White Flame Energy uses two Terex O & K mining shovels, an RH170 and an RH 200, which have the capacity to move 2 million cu yards per month from five seams, primarily the Coalburg, Stockton, and No 5 Block and associated rider seams. The article records conversations on the operations with Mike Vines, the general manager, and Don Nicewonder, the owner of White Flame Energy. 2 photos.

  18. A Neural-Network-Based Approach to White Blood Cell Classification

    Directory of Open Access Journals (Sweden)

    Mu-Chun Su

    2014-01-01

    Full Text Available This paper presents a new white blood cell classification system for the recognition of five types of white blood cells. We propose a new segmentation algorithm for the segmentation of white blood cells from smear images. The core idea of the proposed segmentation algorithm is to find a discriminating region of white blood cells on the HSI color space. Pixels with color lying in the discriminating region described by an ellipsoidal region will be regarded as the nucleus and granule of cytoplasm of a white blood cell. Then, through a further morphological process, we can segment a white blood cell from a smear image. Three kinds of features (i.e., geometrical features, color features, and LDP-based texture features are extracted from the segmented cell. These features are fed into three different kinds of neural networks to recognize the types of the white blood cells. To test the effectiveness of the proposed white blood cell classification system, a total of 450 white blood cells images were used. The highest overall correct recognition rate could reach 99.11% correct. Simulation results showed that the proposed white blood cell classification system was very competitive to some existing systems.

  19. Conditions for accretion-induced collapse of white dwarfs

    International Nuclear Information System (INIS)

    Nomoto, Kenichi; Kondo, Yoji

    1991-01-01

    Recent discovery of an unexpectedly large number of low-mass binary pulsars (LMBPs) in globular clusters has instigated active discussions on the evolutionary origin of binary pulsars. Prompted by the possibility that at least some of LMBPs originate from accretion-induced collapse (AIC) of white dwarfs, a reexamination is conducted as to whether or not AIC occurs for the new models of O + Ne + Mg white dwarfs and solid C + O white dwarfs that can ignite explosive nuclear burning at significantly lower central densities than in the previous models. Even with low critical densities, AIC is still much more likely than explosion for both types of white dwarfs. Possible regions for AIC are presented in a diagram of mass accretion rate vs initial mass of the white dwarfs. 42 refs

  20. THE WHITE DWARF AGE OF NGC 2477

    International Nuclear Information System (INIS)

    Jeffery, Elizabeth J.; Von Hippel, Ted; DeGennaro, Steven; Jefferys, William H.; Van Dyk, David A.; Stein, Nathan

    2011-01-01

    We present deep photometric observations of the open cluster NGC 2477 using HST/WFPC2. By identifying seven cluster white dwarf candidates, we present an analysis of the white dwarf age of this cluster, using both the traditional method of fitting isochrones to the white dwarf cooling sequence, and by employing a new Bayesian statistical technique that has been developed by our group. This new method performs an objective, simultaneous model fit of the cluster and stellar parameters (namely, age, metallicity, distance, reddening, as well as individual stellar masses, mass ratios, and cluster membership) to the photometry. Based on this analysis, we measure a white dwarf age of 1.035 ± 0.054 ± 0.087 Gyr (uncertainties represent the goodness of model fits and discrepancy among models, respectively) in good agreement with the cluster's main-sequence turnoff age. This work is part of our ongoing work to calibrate main-sequence turnoff and white dwarf ages using open clusters, and to improve the precision of cluster ages to the ∼5% level.

  1. Efficient and stable laser-driven white lighting

    Directory of Open Access Journals (Sweden)

    Kristin A. Denault

    2013-07-01

    Full Text Available Laser-based white lighting offers a viable option as an efficient and color-stable high-power solid-state white light source. We show that white light generation is possible using blue or near-UV laser diodes in combination with yellow-emitting cerium-substituted yttrium aluminum garnet (YAG:Ce or a mixture of red-, green-, and blue-emitting phosphors. A variety of correlated color temperatures (CCT are achieved, ranging from cool white light with a CCT of 4400 K using a blue laser diode to a warm white light with a CCT of 2700 K using a near-UV laser diode, with respective color rendering indices of 57 and 95. The luminous flux of these devices are measured to be 252 lm and 53 lm with luminous efficacies of 76 lm/W and 19 lm/W, respectively. An estimation of the maximum efficacy of a device comprising a blue laser diode in combination with YAG:Ce is calculated and the results are used to optimize the device.

  2. Facilitation of Retention by White Noise

    Science.gov (United States)

    Baumeister, Alfred A.; Kistler, Doris

    1975-01-01

    This study attempted to determine if white noise (an arousing stimulus), when presented at the time of recall, facilitates performance of second and fifth grade students, and if this effect generalizes across different kinds of learning tasks. Findings indicate that white noise produces improvements in performance in both age groups. (GO)

  3. Understanding Colombian Amazonian white sand forests

    NARCIS (Netherlands)

    Peñuela-Mora, M.C.

    2014-01-01

    Although progress has been made in studies on white sand forests in the Amazon, there is still a considerable gap in our knowledge of the unique species composition of white sand forests and their structure and dynamics, especially in Western Amazon. This thesis aims to fill this gap by addressing

  4. Measurements of anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter using two Scheimpflug imaging devices

    Directory of Open Access Journals (Sweden)

    Alberto Domínguez-Vicent

    2014-08-01

    Full Text Available Purpose: To compare the ocular anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter, as measured with two different Scheimpflug imaging devices. Methods: This transversal study included 80 right eyes from 80 subjects aged from 20 to 40 years. Their spherical equivalents ranged from -4.25 to +1.00 diopters (D. Each eye's anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter, were measured for far vision using both the Galilei G4 (double Scheimpflug camera and the Pentacam HR (single Scheimpflug camera systems. Results: Mean anterior chamber depths were calculated as 3.12 ± 0.23 mm and 3.19 ± 0.24 mm when measured with the Galilei G4 and the Pentacam HR, respectively. The mean white-to-white distance measured was 11.84 ± 0.31 mm and 11.90 ± 0.43 mm when measured with the Galilei G4 and the Pentacam HR, respectively. Mean pupil diameters were measured as 3.22 ± 0.58 mm and 3.22 ± 0.52 mm when measured with the Galilei G4 and the Pentacam HR, respectively. Finally, the mean anterior chamber angle was 34.30 ± 2.86 degrees when it was measured with the Galilei G4, and 39.26 ± 2.85 degrees when measured with the Pentacam HR. A comparative analysis revealed that the Galilei G4 yielded a significantly lower (P0.05 for both devices were obtained for the white-to-white distance measurements. Conclusion: The Galilei G4 and Pentacam HR Scheimpflug systems cannot be used interchangeably because they produce significant measurement differences.

  5. Straight and White: Talking with My Mouth Full

    Science.gov (United States)

    Myers, W. Benjamin

    2008-01-01

    By using straight and white teeth as a metaphor for a straight and White identity, the author reflects on how this identity is performed, maintained, and often problematic. Using literature about identity performance, three different voices speak to and from straight and White identity. Using irony by blending arrogance and ignorance in the voice…

  6. Working through Whiteness: White, Male College Students Challenging Racism

    Science.gov (United States)

    Cabrera, Nolan L.

    2012-01-01

    This qualitative study relies on Freire's conception of liberatory praxis to examine White male college students' becoming aware of racism and translating awareness into action. The participants developed racial cognizance via cross-racial contact and course content. They also tended to be open to interrogating racism and racial privilege due to…

  7. White-light-emitting supramolecular gels.

    Science.gov (United States)

    Praveen, Vakayil K; Ranjith, Choorikkat; Armaroli, Nicola

    2014-01-07

    Let there be light, let it be white: Recent developments in the use of chromophore-based gels as scaffolds for the assembly of white-light-emitting soft materials have been significant. The main advantage of this approach lies in the facile accommodation of selected luminescent components within the gel. Excitation-energy-transfer processes between these components ultimately generate the desired light output. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Greening of the White House: Six year report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1999-11-01

    The White House, which recently celebrated its 200th birthday, has a long tradition of demonstrating technological innovation. In keeping with that tradition, President Clinton announced the Greening of the White House Initiative on Earth Day 1993. The initiative improves the energy and environmental performance of the White House complex by identifying opportunities to reduce waste, lower energy use, and make an appropriate use of renewable resources, all while improving indoor air quality and building comfort. This report on President Clinton's legacy of greening at the White House summarizes progress made to date and gives an overview of new opportunities identified during the past year. It also includes an environmental history of the White House and a short tour of the buildings that make up the White House complex. Over the past five years, this initiative has involved hundreds of dedicated people from both within and outside government. A description of how they worked together to develop and implement the Greening Plan is also included in this report.

  9. Color Image of Snow White Trenches and Scraping

    Science.gov (United States)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on the 31st Martian day of the mission, or Sol 31 (June 26, 2008), after the May 25, 2008 landing. This image shows the trenches informally called 'Snow White 1' (left), 'Snow White 2' (right), and within the Snow White 2 trench, the smaller scraping area called 'Snow White 3.' The Snow White 3 scraped area is about 5 centimeters (2 inches) deep. The dug and scraped areas are within the diggiing site called 'Wonderland.' The Snow White trenches and scraping prove that scientists can take surface soil samples, subsurface soil samples, and icy samples all from one unit. Scientists want to test samples to determine if some ice in the soil may have been liquid in the past during warmer climate cycles. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver

  10. White plan and crisis management. Help guide for the elaboration of extended white plans and of white plans for health establishments. Issue 2006, appendix to circular nr DHOS/CGR/2006/401 of 2006 September 14

    International Nuclear Information System (INIS)

    2006-01-01

    White plans are specific emergency plans to be implemented in public and private health establishments. While introducing necessary modifications and taking public health policy effects into account, this document first defines crises and their management (levels of intervention from the local to the national level, typology of emergency plans, emergency medical chain, extended white plans). The second part proposes a set of sheets which aim to be a support in the elaboration of the extended white plan and of the white plan. The third part, based on professional contributions and lessons learned, addresses two important issues: firstly, the crisis management exercise, and secondly the hospital under tension and white plan triggering thresholds

  11. Effects of white phosphorus on mallard reproduction

    Science.gov (United States)

    Vann, S.I.; Sparling, D.W.; Ottinger, M.A.

    2000-01-01

    Extensive waterfowl mortality involving thousands of ducks, geese, and swans has occurred annually at Eagle River Flats, Alaska since at least 1982. The primary agent for this mortality has been identified as white phosphorus. Although acute and subacute lethality have been described, sublethal effects are less well known. This study reports on the effects of white phosphorus on reproductive function in the mallard (Anas platyrhynchos) in captivity. Fertility, hatching success, teratogenicity, and egg laying frequency were examined in 70 adult female mallards who received up to 7 daily doses of 0, 0.5, 1.0, and 2.0 mg/kg of white phosphorus. Measurements of fertility and hatchability were reduced by the white phosphorus. Teratogenic effects were observed in embryos from hens dosed at all treatment levels. Egg laying frequency was reduced even at the lowest treatment level; treated hens required a greater number of days to lay a clutch of 12 eggs than control hens. After two doses at 2.0 mg/kg, all females stopped laying completely for a minimum of 10 days and laying frequency was depressed for at least 45 days. Fertility of 10 adult male mallards dosed with 1.0 mg/kg of white phosphorus did not differ from 10 controls, but plasma testosterone levels were significantly (p free-ranging mallards may be impaired if they are exposed to white phosphorus at typical field levels.

  12. White dwarf evolution - Cradle-to-grave constraints via pulsation

    International Nuclear Information System (INIS)

    Kawaler, S.D.

    1990-01-01

    White dwarf evolution, particularly in the early phases, is not very strongly constrained by observation. Fortunately, white dwarfs undergo nonradial pulsation in three distinct regions of the H-R diagram. These pulsations provide accurate masses, surface compositional structure and rotation velocities, and help constrain other important physical properties. We demonstrate the application of the tools of stellar seismology to white dwarf evolution using the hot white dwarf star PG 1159-035 and the cool DAV (or ZZ Ceti) stars as examples. From pulsation studies, significant challenges to the theory of white dwarf evolution emerge. 44 refs

  13. White matter hyperintensities and normal-appearing white matter integrity in the aging brain.

    Science.gov (United States)

    Maniega, Susana Muñoz; Valdés Hernández, Maria C; Clayden, Jonathan D; Royle, Natalie A; Murray, Catherine; Morris, Zoe; Aribisala, Benjamin S; Gow, Alan J; Starr, John M; Bastin, Mark E; Deary, Ian J; Wardlaw, Joanna M

    2015-02-01

    White matter hyperintensities (WMH) of presumed vascular origin are a common finding in brain magnetic resonance imaging of older individuals and contribute to cognitive and functional decline. It is unknown how WMH form, although white matter degeneration is characterized pathologically by demyelination, axonal loss, and rarefaction, often attributed to ischemia. Changes within normal-appearing white matter (NAWM) in subjects with WMH have also been reported but have not yet been fully characterized. Here, we describe the in vivo imaging signatures of both NAWM and WMH in a large group of community-dwelling older people of similar age using biomarkers derived from magnetic resonance imaging that collectively reflect white matter integrity, myelination, and brain water content. Fractional anisotropy (FA) and magnetization transfer ratio (MTR) were significantly lower, whereas mean diffusivity (MD) and longitudinal relaxation time (T1) were significantly higher, in WMH than NAWM (p curve, 0.982; 95% CI, 0.975-0.989). Furthermore, the level of deterioration of NAWM was strongly associated with the severity of WMH, with MD and T1 increasing and FA and MTR decreasing in NAWM with increasing WMH score, a relationship that was sustained regardless of distance from the WMH. These multimodal imaging data indicate that WMH have reduced structural integrity compared with surrounding NAWM, and MD provides the best discriminator between the 2 tissue classes even within the mild range of WMH severity, whereas FA, MTR, and T1 only start reflecting significant changes in tissue microstructure as WMH become more severe. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Major Superficial White Matter Abnormalities in Huntington's Disease

    Science.gov (United States)

    Phillips, Owen R.; Joshi, Shantanu H.; Squitieri, Ferdinando; Sanchez-Castaneda, Cristina; Narr, Katherine; Shattuck, David W.; Caltagirone, Carlo; Sabatini, Umberto; Di Paola, Margherita

    2016-01-01

    Background: The late myelinating superficial white matter at the juncture of the cortical gray and white matter comprising the intracortical myelin and short-range association fibers has not received attention in Huntington's disease. It is an area of the brain that is late myelinating and is sensitive to both normal aging and neurodegenerative disease effects. Therefore, it may be sensitive to Huntington's disease processes. Methods: Structural MRI data from 25 Pre-symptomatic subjects, 24 Huntington's disease patients and 49 healthy controls was run through a cortical pattern-matching program. The surface corresponding to the white matter directly below the cortical gray matter was then extracted. Individual subject's Diffusion Tensor Imaging (DTI) data was aligned to their structural MRI data. Diffusivity values along the white matter surface were then sampled at each vertex point. DTI measures with high spatial resolution across the superficial white matter surface were then analyzed with the General Linear Model to test for the effects of disease. Results: There was an overall increase in the axial and radial diffusivity across much of the superficial white matter (p < 0.001) in Pre-symptomatic subjects compared to controls. In Huntington's disease patients increased diffusivity covered essentially the whole brain (p < 0.001). Changes are correlated with genotype (CAG repeat number) and disease burden (p < 0.001). Conclusions: This study showed broad abnormalities in superficial white matter even before symptoms are present in Huntington's disease. Since, the superficial white matter has a unique microstructure and function these abnormalities suggest it plays an important role in the disease. PMID:27242403

  15. Gill monogenean communities on three commercially important sparid fish in Omani waters

    Directory of Open Access Journals (Sweden)

    Gilha Yoon

    2015-01-01

    Full Text Available The prevalence and intensity of polyopisthocotylean monogeneans on the gills of three commercially important species of sparid caught in Omani coastal waters close to the city port of Muscat were determined and compared. Throughout May 2012 to April 2013, infections on bi-weekly samples of the soldier seabream, Argyrops filamentosus (Valenciennes, 1830, the king soldier seabream, Argyrops spinifer (Forsskål, 1775, and, the silver seabream, Rhabdosargus sabra were evaluated. From a total of 200 specimens (standard length of 26–52 cm, caught by line angling or by traps, at least three species of gill monogenean, namely Omanicotyle [Bivagina] heterospina, Heteromicrocotyla sp. and Microcotyle sp., were commonly encountered. Silver bream, which was infected by all three monogeneans, bore the highest infections (100% prevalence; mean intensity of 20.14 ± 0.92 parasites fish-1, whilst the soldier bream, which was infected only by O. heterospina had the lowest levels of infection (of the three sparids with 63.8% prevalence; mean intensity 5.8 ± 0.17 parasites fish-1. Comments on the distribution of monogeneans on each host are provided but to what extent this is influenced by water current speeds passing through the buccal and opercular cavities, gill morphology, parasite size, and / or the morphology and efficiency of the parasite’s attachment apparatus requires establishing and forms the basis of ongoing investigations.

  16. Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

    Science.gov (United States)

    Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

    2008-01-01

    How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...

  17. ESCO White Paper

    Science.gov (United States)

    EPA developed this white paper to explore energy performance contracting with Energy Service Companies (ESCOs) and its potential to be a best practice for installing solar thermal water heating systems in the commercial and industrial sector.

  18. Heterogeneity in age-related white matter changes

    NARCIS (Netherlands)

    Schmidt, R.; Schmidt, H.; Haybaeck, J.; Loitfelder, M.; Weis, S.; Cavalieri, M.; Seiler, S.; Enzinger, C.; Ropele, S.; Erkinjuntti, T.; Pantoni, L.; Scheltens, P.; Fazekas, F.; Jellinger, K.

    2011-01-01

    White matter changes occur endemically in routine magnetic resonance imaging (MRI) scans of elderly persons. MRI appearance and histopathological correlates of white matter changes are heterogeneous. Smooth periventricular hyperintensities, including caps around the ventricular horns,

  19. White Mango Scale, Aulacaspis tubercularis , Distribution and ...

    African Journals Online (AJOL)

    White Mango Scale, Aulacaspis tubercularis , Distribution and Severity Status in East and West Wollega Zones, ... Among the insect pests attacking mango plant, white mango scale is the most devastating insect pest. ... HOW TO USE AJOL.

  20. Low white blood cell count and cancer

    Science.gov (United States)

    ... gov/ency/patientinstructions/000675.htm Low white blood cell count and cancer To use the sharing features on this page, please enable JavaScript. White blood cells (WBCs) fight infections from bacteria, viruses, fungi, and ...

  1. Evolution of White Dwarf Stars

    OpenAIRE

    L. G. Althaus

    2001-01-01

    This paper is aimed at presenting the main results we have obtained for the study of the evoution of white dwarf stars. The calculations are carried out by means of a detailed evolutionary code based on an updated physical description. In particular, we briefly discuss the results for the evolution of white dwarfs of different stellar masses and chemical composition, and the evolution of whit e dwarfs in the framework of a varying gravitational constant G scenario as well.

  2. Economists and White House Decisions

    OpenAIRE

    Stuart E. Eizenstat

    1992-01-01

    While I served in the White House, [as Assistant to the President for Domestic Affairs and Policy and Executive Director of the White House Domestic Policy Staff from 1977-81], Ph.D. economists occupied the positions of Secretary of Labor, Secretary of Commerce, Secretary of Treasury, Director of the Council on Wage and Price Stability, the President's anti-inflation adviser, Chairman and Council Members of the Council of Economic Advisers, and many other senior positions throughout the gover...

  3. Strong white photoluminescence from annealed zeolites

    International Nuclear Information System (INIS)

    Bai, Zhenhua; Fujii, Minoru; Imakita, Kenji; Hayashi, Shinji

    2014-01-01

    The optical properties of zeolites annealed at various temperatures are investigated for the first time. The annealed zeolites exhibit strong white photoluminescence (PL) under ultraviolet light excitation. With increasing annealing temperature, the emission intensity of annealed zeolites first increases and then decreases. At the same time, the PL peak red-shifts from 495 nm to 530 nm, and then returns to 500 nm. The strongest emission appears when the annealing temperature is 500 °C. The quantum yield of the sample is measured to be ∼10%. The PL lifetime monotonously increases from 223 μs to 251 μs with increasing annealing temperature. The origin of white PL is ascribed to oxygen vacancies formed during the annealing process. -- Highlights: • The optical properties of zeolites annealed at various temperatures are investigated. • The annealed zeolites exhibit strong white photoluminescence. • The maximum PL enhancement reaches as large as 62 times. • The lifetime shows little dependence on annealing temperature. • The origin of white emission is ascribed to the oxygen vacancies

  4. General Relativistic Calculations for White Dwarf Stars

    OpenAIRE

    Mathew, Arun; Nandy, Malay K.

    2014-01-01

    The mass-radius relations for white dwarf stars are investigated by solving the Newtonian as well as Tolman-Oppenheimer-Volkoff (TOV) equations for hydrostatic equilibrium assuming the electron gas to be non-interacting. We find that the Newtonian limiting mass of $1.4562M_\\odot$ is modified to $1.4166M_\\odot$ in the general relativistic case for $^4_2$He (and $^{12}_{\\ 6}$C) white dwarf stars. Using the same general relativistic treatment, the critical mass for $^{56}_{26}$Fe white dwarf is ...

  5. Ex vivo assessment of genotoxicity and cytotoxicity in murine fibroblasts exposed to white MTA or white Portland cement with 15% bismuth oxide.

    Science.gov (United States)

    Zeferino, E G; Bueno, C E S; Oyama, L M; Ribeiro, D A

    2010-10-01

    To evaluate whether white mineral trioxide aggregate (MTA) or white Portland cement with 15% bismuth oxide were able to induce genetic damage and cellular death ex vivo. Aliquots of 1 × 10(4) murine fibroblasts were incubated at 37 °C for 3 h with MTA (white) or white Portland cement with 15% bismuth oxide, at final concentrations ranging from 10 to 1000 μg mL(-1) individually. Data of three independent repeats from the comet assay and the trypan blue exclusion test were assessed by the one-way anova followed by Tukey's test. Mineral trioxide aggregate or Portland cement containing bismuth oxide did not produce genotoxic effects with respect to the single-cell gel (comet) assay data for all concentrations evaluated. Furthermore, no cytotoxicity was observed for MTA or Portland cement. White MTA or white Portland cement containing 15% bismuth oxide were not genotoxic and cytotoxic. © 2010 International Endodontic Journal.

  6. Wide color gamut display with white and emerald backlighting.

    Science.gov (United States)

    Duan, Lvyin; Lei, Zhichun

    2018-02-20

    This paper proposes a wide color gamut approach that uses white and emerald lighting units as the backlight of the liquid crystal display. The white and emerald backlights are controlled by the image to be displayed. The mixing ratio of the white and the emerald lighting is analyzed so that the maximal color gamut coverage ratio can be achieved. Experimental results prove the effectiveness of the wide color gamut approach using white and emerald backlights.

  7. Self-Sorting of White Blood Cells in a Lattice

    Science.gov (United States)

    Carlson, Robert H.; Gabel, Christopher V.; Chan, Shirley S.; Austin, Robert H.; Brody, James P.; James, D. W. Winkelman M.

    1997-09-01

    When a drop of human blood containing red and white blood cells is forced to move via hydrodynamic forces in a lattice of channels designed to mimic the capillary channels, the white cells self-fractionate into the different types of white cells. The pattern of white cells that forms is due to a combination of stretch-activated adhesion of cells with the walls, stochastic sticking probabilities, and heteroavoidance between granulocytes and lymphocytes.

  8. White holes and eternal black holes

    International Nuclear Information System (INIS)

    Hsu, Stephen D H

    2012-01-01

    We investigate isolated white holes surrounded by vacuum, which correspond to the time reversal of eternal black holes that do not evaporate. We show that isolated white holes produce quasi-thermal Hawking radiation. The time reversal of this radiation, incident on a black hole precursor, constitutes a special preparation that will cause the black hole to become eternal. (paper)

  9. White noise solutions to the stochastic mKdV equation

    International Nuclear Information System (INIS)

    Zhang Zhongjun; Wei Caimin

    2009-01-01

    In this paper, we present the white noise solutions of the stochastic mKdV equation via the Hermite transformation and variable-coefficient generalized projected Ricatti equation expansion method. These solutions include white noise solitary wave solutions, white noise soliton-like solutions and white noise trigonometric function solutions.

  10. White dwarf planets

    Directory of Open Access Journals (Sweden)

    Bonsor Amy

    2013-04-01

    Full Text Available The recognition that planets may survive the late stages of stellar evolution, and the prospects for finding them around White Dwarfs, are growing. We discuss two aspects governing planetary survival through stellar evolution to the White Dwarf stage. First we discuss the case of a single planet, and its survival under the effects of stellar mass loss, radius expansion, and tidal orbital decay as the star evolves along the Asymptotic Giant Branch. We show that, for stars initially of 1 − 5 M⊙, any planets within about 1 − 5 AU will be engulfed, this distance depending on the stellar and planet masses and the planet's eccentricity. Planets engulfed by the star's envelope are unlikely to survive. Hence, planets surviving the Asymptotic Giant Branch phase will probably be found beyond ∼ 2 AU for a 1  M⊙ progenitor and ∼ 10 AU for a 5 M⊙ progenitor. We then discuss the evolution of two-planet systems around evolving stars. As stars lose mass, planet–planet interactions become stronger, and many systems stable on the Main Sequence become destabilised following evolution of the primary. The outcome of such instabilities is typically the ejection of one planet, with the survivor being left on an eccentric orbit. These eccentric planets could in turn be responsible for feeding planetesimals into the neighbourhood of White Dwarfs, causing observed pollution and circumstellar discs.

  11. ON THE EVOLUTION OF MAGNETIC WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Tremblay, P.-E. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Fontaine, G.; Brassard, P. [Département de Physique, Université de Montréal, C. P. 6128, Succursale Centre-Ville, Montréal, QC H3C 3J7 (Canada); Freytag, B. [Department of Physics and Astronomy at Uppsala University, Regementsvägen 1, Box 516, SE-75120 Uppsala (Sweden); Steiner, O. [Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, D-79104 Freiburg (Germany); Ludwig, H.-G. [Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, D-69117 Heidelberg (Germany); Steffen, M. [Leibniz-Institut für Astrophysik Potsdam, An der Sternwarte 16, D-14482 Potsdam (Germany); Wedemeyer, S., E-mail: tremblay@stsci.edu [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway)

    2015-10-10

    We present the first radiation magnetohydrodynamic simulations of the atmosphere of white dwarf stars. We demonstrate that convective energy transfer is seriously impeded by magnetic fields when the plasma-β parameter, the thermal-to-magnetic-pressure ratio, becomes smaller than unity. The critical field strength that inhibits convection in the photosphere of white dwarfs is in the range B = 1–50 kG, which is much smaller than the typical 1–1000 MG field strengths observed in magnetic white dwarfs, implying that these objects have radiative atmospheres. We have employed evolutionary models to study the cooling process of high-field magnetic white dwarfs, where convection is entirely suppressed during the full evolution (B ≳ 10 MG). We find that the inhibition of convection has no effect on cooling rates until the effective temperature (T{sub eff}) reaches a value of around 5500 K. In this regime, the standard convective sequences start to deviate from the ones without convection due to the convective coupling between the outer layers and the degenerate reservoir of thermal energy. Since no magnetic white dwarfs are currently known at the low temperatures where this coupling significantly changes the evolution, the effects of magnetism on cooling rates are not expected to be observed. This result contrasts with a recent suggestion that magnetic white dwarfs with T{sub eff} ≲ 10,000 K cool significantly slower than non-magnetic degenerates.

  12. Atrophy of gray and white matters in the brain during aging

    International Nuclear Information System (INIS)

    Takeda, Shumpei; Matsuzawa, Taiju; Ito, Hisao.

    1984-01-01

    We studied atrophy of gray and white matter during aging in 57 males and 44 females with no neurological disturbances using x-ray computed tomography. The ages ranged from 12 to 80 years. Brain atrophy was expressed as brain volume index: 100% x [(brain volume/cranial cavity volume) in individual subjects]/[(brain volume/cranial cavity volume) in normal subjects of 20-39 years]. Atrophy of gray and white matter volume was expressed as gray and white matter volume indices: 100% x (apparent gray or white matter volume index in individual subjects)/(apparent gray or white matter volume index in normal subjects whose brain volume index was greater than 98%), where apparent gray and white matter volume indices were expressed as 100% x [(gray or white matter volume/cranial cavity volume) in individual subjects]/[(gray or white matter volume/cranial cavity volume) in normal subjects of 20-39 years]. Both the gray and white matter volume indices changed proportionally to the brain volume index (p<0.001). As the brain atrophy advanced, the gray matter volume index decreased more than the white matter volume index (P<0.001). Decrease in the gray and white matter volume indices was statistically significant only in seventies (P<0.002 for gray matter, P<0.05 for white matter). (author)

  13. Size of the great white shark (carcharodon).

    Science.gov (United States)

    Randall, J E

    1973-07-13

    The maximum length of 36.5 feet (11.1 meters) attributed to the white shark (Carcharodon carcharias) by Günther and others is a mistake. Examination of the jaws and teeth of the specimen referred to by Günther and comparison with the jaws of white sharks of known length revealed a length of about 17 feet ( approximately 5 meters). The largest white shark reliably measured was a 21-foot (6.4-meter) individual from Cuba. Bites on whale carcasses found off southern Australia suggest that white sharks as long as 25 or 26 feet (7 (1/2) or 8 meters) exist today. The size of extinct Carcharodon has also been grossly exaggerated. Based on a projection of a curve of tooth size of Recent Carcharodon carcharias, the largest fossil Carcharodon were about 43 feet ( approximately 13 meters) long.

  14. Ages of white dwarf-red subdwarf systems

    Directory of Open Access Journals (Sweden)

    Hektor Monteiro

    2006-01-01

    Full Text Available We provide the first age estimates for two recently discovered white dwarf-red subdwarf systems, LHS 193AB and LHS 300AB. These systems provide a new opportunity for linking the reliable age estimates for the white dwarfs to the (measurable metallicities of the red subdwarfs. We have obtained precise photometry in the VJRKCIKCJH bands and spectroscopy covering from 6,000°A to 9,000°A (our spectral coveragefor the two new systems, as well as for a comparison white dwarfmain sequence red dwarf system, GJ 283 AB. Using model grids, we estimate the cooling age as well as temperature, surface gravity, mass, progenitor mass and total lifetimes of the white dwarfs. The results indicate that the two new systems are probably ancient thick disk objects with ages of at least 6-9 gigayears (Gyr.

  15. AMP-Activated Kinase (AMPK Activation by AICAR in Human White Adipocytes Derived from Pericardial White Adipose Tissue Stem Cells Induces a Partial Beige-Like Phenotype.

    Directory of Open Access Journals (Sweden)

    Omar Abdul-Rahman

    Full Text Available Beige adipocytes are special cells situated in the white adipose tissue. Beige adipocytes, lacking thermogenic cues, morphologically look quite similar to regular white adipocytes, but with a markedly different response to adrenalin. White adipocytes respond to adrenergic stimuli by enhancing lipolysis, while in beige adipocytes adrenalin induces mitochondrial biogenesis too. A key step in the differentiation and function of beige adipocytes is the deacetylation of peroxisome proliferator-activated receptor (PPARγ by SIRT1 and the consequent mitochondrial biogenesis. AMP-activated protein kinase (AMPK is an upstream activator of SIRT1, therefore we set out to investigate the role of AMPK in beige adipocyte differentiation using human adipose-derived mesenchymal stem cells (hADMSCs from pericardial adipose tissue. hADMSCs were differentiated to white and beige adipocytes and the differentiation medium of the white adipocytes was supplemented with 100 μM [(2R,3S,4R,5R-5-(4-Carbamoyl-5-aminoimidazol-1-yl-3,4-dihydroxyoxolan-2-yl]methyl dihydrogen phosphate (AICAR, a known activator of AMPK. The activation of AMPK with AICAR led to the appearance of beige-like morphological properties in differentiated white adipocytes. Namely, smaller lipid droplets appeared in AICAR-treated white adipocytes in a similar fashion as in beige cells. Moreover, in AICAR-treated white adipocytes the mitochondrial network was more fused than in white adipocytes; a fused mitochondrial system was characteristic to beige adipocytes. Despite the morphological similarities between AICAR-treated white adipocytes and beige cells, functionally AICAR-treated white adipocytes were similar to white adipocytes. We were unable to detect increases in basal or cAMP-induced oxygen consumption rate (a marker of mitochondrial biogenesis when comparing control and AICAR-treated white adipocytes. Similarly, markers of beige adipocytes such as TBX1, UCP1, CIDEA, PRDM16 and TMEM26 remained

  16. AGREEMENT BETWEEN THE WHITE MATTER CONNECTIVITY BASED ON THE TENSOR-BASED MORPHOMETRY AND THE VOLUMETRIC WHITE MATTER PARCELLATIONS BASED ON DIFFUSION TENSOR IMAGING

    OpenAIRE

    Kim, Seung-Goo; Lee, Hyekyoung; Chung, Moo K.; Hanson, Jamie L.; Avants, Brian B.; Gee, James C.; Davidson, Richard J.; Pollak, Seth D.

    2012-01-01

    We are interested in investigating white matter connectivity using a novel computational framework that does not use diffusion tensor imaging (DTI) but only uses T1-weighted magnetic resonance imaging. The proposed method relies on correlating Jacobian determinants across different voxels based on the tensor-based morphometry (TBM) framework. In this paper, we show agreement between the TBM-based white matter connectivity and the DTI-based white matter atlas. As an application, altered white ...

  17. Exposing Whiteness in Higher Education: White Male College Students Minimizing Racism, Claiming Victimization, and Recreating White Supremacy

    Science.gov (United States)

    Cabrera, Nolan León

    2014-01-01

    This research critically examines racial views and experiences of 12 white men in a single higher education institution via semi-structured interviews. Participants tended to utilize individualized definitions of racism and experience high levels of racial segregation in both their pre-college and college environments. This corresponded to…

  18. Socioeconomic status, white matter, and executive function in children.

    Science.gov (United States)

    Ursache, Alexandra; Noble, Kimberly G

    2016-10-01

    A growing body of evidence links socioeconomic status (SES) to children's brain structure. Few studies, however, have specifically investigated relations of SES to white matter structure. Further, although several studies have demonstrated that family SES is related to development of brain areas that support executive functions (EF), less is known about the role that white matter structure plays in the relation of SES to EF. One possibility is that white matter differences may partially explain SES disparities in EF (i.e., a mediating relationship). Alternatively, SES may differentially shape brain-behavior relations such that the relation of white matter structure to EF may differ as a function of SES (i.e., a moderating relationship). In a diverse sample of 1082 children and adolescents aged 3-21 years, we examined socioeconomic disparities in white matter macrostructure and microstructure. We further investigated relations between family SES, children's white matter volume and integrity in tracts supporting EF, and performance on EF tasks. Socioeconomic status was associated with fractional anisotropy (FA) and volume in multiple white matter tracts. Additionally, family income moderated the relation between white matter structure and cognitive flexibility. Specifically, across multiple tracts of interest, lower FA or lower volume was associated with reduced cognitive flexibility among children from lower income families. In contrast, children from higher income families showed preserved cognitive flexibility in the face of low white matter FA or volume. SES factors did not mediate or moderate links between white matter and either working memory or inhibitory control. This work adds to a growing body of literature suggesting that the socioeconomic contexts in which children develop not only shape cognitive functioning and its underlying neurobiology, but may also shape the relations between brain and behavior.

  19. Virgin microplastics are not causing imminent harm to fish after dietary exposure

    DEFF Research Database (Denmark)

    Jovanović, Boris; Gökdağ, Kerem; Güven, Olgaç

    2018-01-01

    Among aquatic organisms, fish are particularly susceptible to ingesting microplastic particles due to their attractive coloration, buoyancy, and resemblance to food. However, in previous experimental setups, fish were usually exposed to unrealistically high concentrations of microplastics......, or the microplastics were deliberately contaminated with persistent organic chemicals; also, in many experiments, the fish were exposed only during the larval stages. The present study investigated the effects of virgin microplastics in gilt-head seabream (Sparus aurata) after 45 days’ exposure at 0.1 g kg−1...... of virgin microplastics does not cause imminent harm to the adult gilt-head seabream during 45 days of exposure and an additional 30 days of depuration. The retention of virgin microplastics in the gastrointestinal tract was fairly low, indicating effective elimination of microplastics from the body...

  20. White matter volume changes in people who develop psychosis.

    Science.gov (United States)

    Walterfang, Mark; McGuire, Philip K; Yung, Alison R; Phillips, Lisa J; Velakoulis, Dennis; Wood, Stephen J; Suckling, John; Bullmore, Edward T; Brewer, Warrick; Soulsby, Bridget; Desmond, Patricia; McGorry, Patrick D; Pantelis, Christos

    2008-09-01

    Grey matter changes have been described in individuals who are pre- and peri-psychotic, but it is unclear if these changes are accompanied by changes in white matter structures. To determine whether changes in white matter occur prior to and with the transition to psychosis in individuals who are pre-psychotic who had previously demonstrated grey matter reductions in frontotemporal regions. We used magnetic resonance imaging (MRI) to examine regional white matter volume in 75 people with prodromal symptoms. A subset of the original group (n=21) were rescanned at 12-18 months to determine white matter volume changes. Participants were retrospectively categorised according to whether they had or had not developed psychosis at follow-up. Comparison of the baseline MRI data from these two subgroups revealed that individuals who later developed psychosis had larger volumes of white matter in the frontal lobe, particularly in the left hemisphere. Longitudinal comparison of data in individuals who developed psychosis revealed a reduction in white matter volume in the region of the left fronto-occipital fasciculus. Participants who had not developed psychosis showed no reductions in white matter volume but increases in a region subjacent to the right inferior parietal lobule. The reduction in volume of white matter near the left fronto-occipital fasciculus may reflect a change in this tract in association with the onset of frank psychosis.

  1. Shades of white : diffusion properties of T1- and FLAIR-defined white matter signal abnormalities differ in stages from cognitively normal to dementia

    NARCIS (Netherlands)

    Riphagen, Joost M.; Gronenschild, Ed HBM; Salat, David H.; Freeze, Whitney M.; Ivanov, Dimo; Clerx, Lies; Verhey, Frans R. J.; Aalten, Pauline; Jacobs, Heidi I. L.

    The underlying pathology of white matter signal abnormalities (WMSAs) is heterogeneous and may vary dependent on the magnetic resonance imaging contrast used to define them. We investigated differences in white matter diffusivity as an indicator for white matter integrity underlying WMSA based on

  2. The Color of Supremacy: Beyond the Discourse of "White Privilege"

    Science.gov (United States)

    Leonardo, Zeus

    2004-01-01

    In the last decade, the study of white privilege has reached currency in the educational and social science literature. Concerned with the circuits and meanings of whiteness in everyday life, scholars have exposed the codes of white culture, worldview of the white imaginary, and assumptions of the invisible marker that depends on the racial other…

  3. White noise calculus and Fock space

    CERN Document Server

    Obata, Nobuaki

    1994-01-01

    White Noise Calculus is a distribution theory on Gaussian space, proposed by T. Hida in 1975. This approach enables us to use pointwise defined creation and annihilation operators as well as the well-established theory of nuclear space.This self-contained monograph presents, for the first time, a systematic introduction to operator theory on fock space by means of white noise calculus. The goal is a comprehensive account of general expansion theory of Fock space operators and its applications. In particular,first order differential operators, Laplacians, rotation group, Fourier transform and their interrelations are discussed in detail w.r.t. harmonic analysis on Gaussian space. The mathematical formalism used here is based on distribution theory and functional analysis , prior knowledge of white noise calculus is not required.

  4. Family identity: black-white interracial family health experience.

    Science.gov (United States)

    Byrd, Marcia Marie; Garwick, Ann Williams

    2006-02-01

    The purpose of this interpretive descriptive study was to describe how eight Black-White couples with school-aged children constructed their interracial family identity through developmental transitions and interpreted race to their children. Within and across-case data analytic strategies were used to identify commonalities and variations in how Black men and White women in couple relationships formed their family identities over time. Coming together was the core theme described by the Black-White couples as they negotiated the process of forming a family identity. Four major tasks in the construction of interracial family identity emerged: (a) understanding and resolving family of origin chaos and turmoil, (b) transcending Black-White racial history, (c) articulating the interracial family's racial standpoint, and (d) explaining race to biracial children across the developmental stages. The findings guide family nurses in promoting family identity formation as a component of family health within the nurse-family partnership with Black-White mixed-race families.

  5. Is EG 50 a White or Strange Dwarf?

    Science.gov (United States)

    Hajyan, G. S.; Vartanyan, Yu. L.

    2017-12-01

    The time dependences of the luminosity of a white dwarf and four strange dwarfs with masses of 0.5 M (the mass of the white dwarf EG 50 with a surface temperature of 2.1·104 K) are determined taking neutrino energy losses into account. It was assumed that these configurations radiate only at the expense of thermal energy reserves. It is shown that the sources of thermal energy owing to nonequilibrium b-processes and the phenomenon of crystallization of electron-nuclear matter are insignificant in determining the cooling time of white and strange dwarfs with masses of 0.5 M⨀. It is shown that in this approximation the time dependences of the luminosity of white and strange dwarfs with masses of 0.5 M⨀ differ significantly only for surface temperatures TR≥7·104 K, so it is impossible to determine whether EG 50 is a white or strange dwarf based on the cooling time.

  6. White piedra in a mother and daughter.

    Science.gov (United States)

    Roshan, Anupama S; Janaki, C; Parveen, B

    2009-07-01

    White Piedra is a superficial fungal infection of the hair caused by Trichosporon asahii. It is also known as trichomycosis nodosa or trichomycosis nodularis. We report two cases of White Piedra in a mother and her daughter for the rarity of such occurrence.

  7. WHITE SPACE DALAM IKLAN DI MEDIA CETAK

    Directory of Open Access Journals (Sweden)

    Andrian D. Hagijanto

    1999-01-01

    Full Text Available Readers are often unware of advertisments published in print media%2C therefore the elements of communication design composed in the promotion process fail to reach the objectives. One of the methods use to gain attention from the readers so they focus their vision to the advertisment is by presenting the lay out using white space. This article is to discuss about white space in media advertisments%2C especially newspaper and magazines. Abstract in Bahasa Indonesia : Iklan pada media cetak terkadang dilewati begitu saja oleh pembaca%2C sehingga proses promosi yang dikemas dengan elemen desain komunikasi visual itu gagal mencapai tujuannya. Salah satu cara untuk menarik perhatian pembaca agar menghentikan sejenak kedua matanya dan mengamati iklan adalah dengan menciptakan layout iklan lewat peranan white space. Tulisan ini akan membahas mengenai white space di dalam iklan media cetak%2C khususnya koran dan majalah.

  8. Evidence for Functional Networks within the Human Brain's White Matter.

    Science.gov (United States)

    Peer, Michael; Nitzan, Mor; Bick, Atira S; Levin, Netta; Arzy, Shahar

    2017-07-05

    Investigation of the functional macro-scale organization of the human cortex is fundamental in modern neuroscience. Although numerous studies have identified networks of interacting functional modules in the gray-matter, limited research was directed to the functional organization of the white-matter. Recent studies have demonstrated that the white-matter exhibits blood oxygen level-dependent signal fluctuations similar to those of the gray-matter. Here we used these signal fluctuations to investigate whether the white-matter is organized as functional networks by applying a clustering analysis on resting-state functional MRI (RSfMRI) data from white-matter voxels, in 176 subjects (of both sexes). This analysis indicated the existence of 12 symmetrical white-matter functional networks, corresponding to combinations of white-matter tracts identified by diffusion tensor imaging. Six of the networks included interhemispheric commissural bridges traversing the corpus callosum. Signals in white-matter networks correlated with signals from functional gray-matter networks, providing missing knowledge on how these distributed networks communicate across large distances. These findings were replicated in an independent subject group and were corroborated by seed-based analysis in small groups and individual subjects. The identified white-matter functional atlases and analysis codes are available at http://mind.huji.ac.il/white-matter.aspx Our results demonstrate that the white-matter manifests an intrinsic functional organization as interacting networks of functional modules, similarly to the gray-matter, which can be investigated using RSfMRI. The discovery of functional networks within the white-matter may open new avenues of research in cognitive neuroscience and clinical neuropsychiatry. SIGNIFICANCE STATEMENT In recent years, functional MRI (fMRI) has revolutionized all fields of neuroscience, enabling identifications of functional modules and networks in the human

  9. MR imaging of white matter lesions in AIDS

    International Nuclear Information System (INIS)

    Olsen, W.L.; Longo, F.; Norman, D.

    1987-01-01

    Autopsy reports have shown white-matter abnormalities from infection of the brain by the human immunodeficiency virus (HIV), the agent that causes acquired immunodeficiency syndrome (AIDS). The authors observed abnormal signal on T2-weighted images in the white matter of approximately one third of all AIDS patients. Of 50 patients with white-matter lesions, approximately two thirds had no clinical or biopsy evidence of cytomegalovirus, toxoplasmosis, PML, or lymphoma. Several patients were shown at autopsy to have isolated evidence of HIV encephalitis. The authors conclude that white-matter lesions are common in AIDS and are frequently caused by infection with HIV. Some MR findings may be helpful in characterizing these lesions, but the various etiologies are often indistinguishable

  10. White-Light Emission from Layered Halide Perovskites.

    Science.gov (United States)

    Smith, Matthew D; Karunadasa, Hemamala I

    2018-03-20

    With nearly 20% of global electricity consumed by lighting, more efficient illumination sources can enable massive energy savings. However, effectively creating the high-quality white light required for indoor illumination remains a challenge. To accurately represent color, the illumination source must provide photons with all the energies visible to our eye. Such a broad emission is difficult to achieve from a single material. In commercial white-light sources, one or more light-emitting diodes, coated by one or more phosphors, yield a combined emission that appears white. However, combining emitters leads to changes in the emission color over time due to the unequal degradation rates of the emitters and efficiency losses due to overlapping absorption and emission energies of the different components. A single material that emits broadband white light (a continuous emission spanning 400-700 nm) would obviate these problems. In 2014, we described broadband white-light emission upon near-UV excitation from three new layered perovskites. To date, nine white-light-emitting perovskites have been reported by us and others, making this a burgeoning field of study. This Account outlines our work on understanding how a bulk material, with no obvious emissive sites, can emit every color of the visible spectrum. Although the initial discoveries were fortuitous, our understanding of the emission mechanism and identification of structural parameters that correlate with the broad emission have now positioned us to design white-light emitters. Layered hybrid halide perovskites feature anionic layers of corner-sharing metal-halide octahedra partitioned by organic cations. The narrow, room-temperature photoluminescence of lead-halide perovskites has been studied for several decades, and attributed to the radiative recombination of free excitons (excited electron-hole pairs). We proposed that the broad white emission we observed primarily stems from exciton self-trapping. Here, the

  11. NUCLEAR CONDENSATE AND HELIUM WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Bedaque, Paulo F.; Berkowitz, Evan [Maryland Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, MD (United States); Cherman, Aleksey, E-mail: bedaque@umd.edu, E-mail: evanb@umd.edu, E-mail: a.cherman@damtp.cam.ac.uk [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA (United Kingdom)

    2012-04-10

    We consider a high-density region of the helium phase diagram, where the nuclei form a Bose-Einstein condensate rather than a classical plasma or a crystal. Helium in this phase may be present in helium-core white dwarfs. We show that in this regime there is a new gapless quasiparticle not previously noticed, arising when the constraints imposed by gauge symmetry are taken into account. The contribution of this quasiparticle to the specific heat of a white dwarf core turns out to be comparable in a range of temperatures to the contribution from the particle-hole excitations of the degenerate electrons. The specific heat in the condensed phase is two orders of magnitude smaller than in the uncondensed plasma phase, which is the ground state at higher temperatures, and four orders of magnitude smaller than the specific heat that an ion lattice would provide, if formed. Since the specific heat of the core is an important input for setting the rate of cooling of a white dwarf star, it may turn out that such a change in the thermal properties of the cores of helium white dwarfs has observable implications.

  12. NUCLEAR CONDENSATE AND HELIUM WHITE DWARFS

    International Nuclear Information System (INIS)

    Bedaque, Paulo F.; Berkowitz, Evan; Cherman, Aleksey

    2012-01-01

    We consider a high-density region of the helium phase diagram, where the nuclei form a Bose-Einstein condensate rather than a classical plasma or a crystal. Helium in this phase may be present in helium-core white dwarfs. We show that in this regime there is a new gapless quasiparticle not previously noticed, arising when the constraints imposed by gauge symmetry are taken into account. The contribution of this quasiparticle to the specific heat of a white dwarf core turns out to be comparable in a range of temperatures to the contribution from the particle-hole excitations of the degenerate electrons. The specific heat in the condensed phase is two orders of magnitude smaller than in the uncondensed plasma phase, which is the ground state at higher temperatures, and four orders of magnitude smaller than the specific heat that an ion lattice would provide, if formed. Since the specific heat of the core is an important input for setting the rate of cooling of a white dwarf star, it may turn out that such a change in the thermal properties of the cores of helium white dwarfs has observable implications.

  13. AGREEMENT BETWEEN THE WHITE MATTER CONNECTIVITY BASED ON THE TENSOR-BASED MORPHOMETRY AND THE VOLUMETRIC WHITE MATTER PARCELLATIONS BASED ON DIFFUSION TENSOR IMAGING.

    Science.gov (United States)

    Kim, Seung-Goo; Lee, Hyekyoung; Chung, Moo K; Hanson, Jamie L; Avants, Brian B; Gee, James C; Davidson, Richard J; Pollak, Seth D

    2012-01-01

    We are interested in investigating white matter connectivity using a novel computational framework that does not use diffusion tensor imaging (DTI) but only uses T1-weighted magnetic resonance imaging. The proposed method relies on correlating Jacobian determinants across different voxels based on the tensor-based morphometry (TBM) framework. In this paper, we show agreement between the TBM-based white matter connectivity and the DTI-based white matter atlas. As an application, altered white matter connectivity in a clinical population is determined.

  14. Educational Achievement and Black-White Inequality. Statistical Analysis Report.

    Science.gov (United States)

    Jacobson, Jonathan; Olsen, Cara; Rice, Jennifer King; Sweetland, Stephen

    This study explored relationships between black-white differences in educational achievement and black-white differences in various educational and economic outcomes. Three data sets examined the extent to which black-white differences in labor market outcomes, in educational attainment, and in mathematics and reading achievement were present for…

  15. A Weberian medievalist : Hayden White in the 1950s

    NARCIS (Netherlands)

    Paul, Herman

    This article is the first in-depth examination of Hayden White's earliest writings. Ignored by most scholars of White's thought, these medievalist studies, dating from the mid-1950s to the early 1960s, offer a fascinating insight into the young White's approach to history. Much unlike his later,

  16. Observations of the "egg white injury" in ants.

    Directory of Open Access Journals (Sweden)

    Laure-Anne Poissonnier

    Full Text Available A key determinant of the relationship between diet and longevity is the balance of protein to carbohydrate in the diet. Eating excess protein relative to carbohydrate shortens lifespan in solitary and social insects. Here we explored how lifespan and behavior in ants was affected by the quality of protein ingested and the presence of associated antinutrients (i.e. compounds that interfere with the absorption of nutrients. We tested diets prepared with either egg white protein only or a protein mixture. Egg white contains an anti-nutrient called avidin. Avidin binds to the B vitamin biotin, preventing its absorption. First, we demonstrate that an egg-white diet was twice as deleterious as a protein-mixture diet. Second, we show that ingestion of egg-white diet drastically affected social behavior, triggering elevated levels of aggression within the colony. Lastly, we reveal that by adding biotin to the egg white diet we were able to lessen its detrimental effects. This latest result suggests that ants suffered biotin deficiency when fed the egg white diet. In conclusion, anti-nutrients were known to affect health and performance of animals, but this is the first study showing that anti-nutrients also lead to severe changes in behavior.

  17. Secondary poisoning of kestrels by white phosphorus

    Science.gov (United States)

    Sparling, D.W.; Federoff, N.E.

    1997-01-01

    Since 1982, extensive waterfowl mortality due to white phosphorus (P4) has been observed at Eagle River Flats, a tidal marsh near Anchorage, Alaska. Ducks and swans that ingest P4 pellets become lethargic and may display severe convulsions. Intoxicated waterfowl attract raptors and gulls that feed on dead or dying birds. To determine if avian predators can be affected by secondary poisoning, we fed American kestrels (Falco sparverius) 10-day-old domestic chickens that had been dosed with white phosphorus. Eight of 15 kestrels fed intact chicks with a pellet of P4 implanted in their crops died within seven days. Three of 15 kestrels fed chicks that had their upper digestive tracts removed to eliminate any pellets of white phosphorus also died. Hematocrit and hemoglobin in kestrels decreased whereas lactate dehydrogenaseL, glucose, and alanine aminotransferase levels in plasma increased with exposure to contaminated chicks. Histological examination of liver and kidneys showed that the incidence and severity of lesions increased when kestrels were fed contaminated chicks. White phosphorus residues were measurable in 87% of the kestrels dying on study and 20% of the survivors. This study shows that raptors can become intoxicated either by ingesting portions of digestive tracts containing white phosphorus pellets or by consuming tissues of P4 contaminated prey.

  18. Recent developments in white light emitting diodes

    Science.gov (United States)

    Lohe, P. P.; Nandanwar, D. V.; Belsare, P. D.; Moharil, S. V.

    2018-05-01

    In the recent years solid state lighting based on LEDs has revolutionized lighting technology. LEDs have many advantages over the conventional lighting based on fluorescent and incandescent lamps such as mercury free, high conversion efficiency of electrical energy into light, long lifetime reliability and ability to use with many types of devices. LEDs have emerged as a new potentially revolutionary technology that could save up to half of energy used for lighting applications. White LEDs would be the most important light source in the future, so much so that this aspect had been highlighted by the Nobel committee during the award of 2014 Nobel Prize for Physics. Recent advancement in the fabrication of GaN chip capable of emitting in blue and near UV region paved way for fabrication of white LED lamps. Mainly there are two approaches used for preparing white emitting solid state lamp. In the first approach blue light (λ=450 nm) emitted from the InGaN LED chip is partially absorbed by the YAG:Ce3+ phosphor coated on it and re-emitted as yellow fluorescence. A white light can be generated by the combination of blue + yellow emission bands. These lamps are already available. But they are suffering from major drawback that their Colour Rendering Index (CRI) is low. In the second approach, white LEDs are made by coating near ultraviolet emitting (360 to 410nm) LED with a mixture of high efficiency red, green and blue emitting phosphors, analogous to the fluorescent lamp. This method yields lamps with better color rendition. Addition of a yellow emitting phosphor improves CRI further. However conversion efficiency is compromised to some extent. Further the cost of near UV emitting chip is very high compared to blue emitting chips. Thus cost and light output wise, near UV chips are much inferior to blue chips. Recently some rare earth activated oxynitrides, silicates, fluorides have emerged as an important family of luminescent materials for white LED application

  19. 75 FR 78875 - White House Council for Community Solutions

    Science.gov (United States)

    2010-12-17

    ... Order 13560 of December 14, 2010 White House Council for Community Solutions By the authority vested in... White House Council for Community Solutions (Council) within the Corporation for National and Community.... (Presidential Sig.) THE WHITE HOUSE, December 14, 2010. [FR Doc. 2010-31878 Filed 12-16-10; 8:45 am] Billing...

  20. Decoding white coat hypertension

    Science.gov (United States)

    Bloomfield, Dennis A; Park, Alex

    2017-01-01

    There is arguably no less understood or more intriguing problem in hypertension that the “white coat” condition, the standard concept of which is significantly blood pressure reading obtained by medical personnel of authoritative standing than that obtained by more junior and less authoritative personnel and by the patients themselves. Using hospital-initiated ambulatory blood pressure monitoring, the while effect manifests as initial and ending pressure elevations, and, in treated patients, a low daytime profile. The effect is essentially systolic. Pure diastolic white coat hypertension appears to be exceedingly rare. On the basis of the studies, we believe that the white coat phenomenon is a common, periodic, neuro-endocrine reflex conditioned by anticipation of having the blood pressure taken and the fear of what this measurement may indicate concerning future illness. It does not change with time, or with prolonged association with the physician, particularly with advancing years, it may be superimposed upon essential hypertension, and in patients receiving hypertensive medication, blunting of the nighttime dip, which occurs in about half the patients, may be a compensatory mechanisms, rather than an indication of cardiovascular risk. Rather than the blunted dip, the morning surge or the widened pulse pressure, cardiovascular risk appears to be related to elevation of the average night time pressure. PMID:28352632

  1. Genesis of magnetic fields in isolated white dwarfs

    Science.gov (United States)

    Briggs, Gordon P.; Ferrario, Lilia; Tout, Christopher A.; Wickramasinghe, Dayal T.

    2018-05-01

    A dynamo mechanism driven by differential rotation when stars merge has been proposed to explain the presence of strong fields in certain classes of magnetic stars. In the case of the high field magnetic white dwarfs (HFMWDs), the site of the differential rotation has been variously thought to be the common envelope, the hot outer regions of a merged degenerate core or an accretion disc formed by a tidally disrupted companion that is subsequently accreted by a degenerate core. We have shown previously that the observed incidence of magnetism and the mass distribution in HFMWDs are consistent with the hypothesis that they are the result of merging binaries during common envelope evolution. Here we calculate the magnetic field strengths generated by common envelope interactions for synthetic populations using a simple prescription for the generation of fields and find that the observed magnetic field distribution is also consistent with the stellar merging hypothesis. We use the Kolmogorov-Smirnov test to study the correlation between the calculated and the observed field strengths and find that it is consistent for low envelope ejection efficiency. We also suggest that field generation by the plunging of a giant gaseous planet on to a white dwarf may explain why magnetism among cool white dwarfs (including DZ white dwarfs) is higher than among hot white dwarfs. In this picture a super-Jupiter residing in the outer regions of the white dwarf's planetary system is perturbed into a highly eccentric orbit by a close stellar encounter and is later accreted by the white dwarf.

  2. Overset Wolff-Parkinson-White-syndrom

    DEFF Research Database (Denmark)

    Nielsen, Trine Skov; Dalager, Søren; Larsen, Maiken Kudahl

    2010-01-01

    An autopsy in a 28-year-old man did not explain the cause of sudden unexpected death. However, a history of episodes with tachycardia and dizziness and a reassessed previous electrocardiogram exhibiting ventricular pre-excitation was consistent with Wolff-Parkinson-White (WPW) syndrome. In this p......An autopsy in a 28-year-old man did not explain the cause of sudden unexpected death. However, a history of episodes with tachycardia and dizziness and a reassessed previous electrocardiogram exhibiting ventricular pre-excitation was consistent with Wolff-Parkinson-White (WPW) syndrome...

  3. Social imaginaries, sperm and whiteness

    DEFF Research Database (Denmark)

    Andreassen, Rikke

    2017-01-01

    media coverage of these new families, this article explores contemporary constructions of race, especially whiteness, and gender, and shows how imaginaries of Vikings, genes and white superiority circulate in British media and among British mothers. The article illustrates how a racial discourse, which......This article analyses narratives about so-called Viking babies and Viking sperm. Over the last few years an increasing number of British single women and lesbian couples have been creating families by becoming pregnant with Danish donor sperm, termed ‘Viking sperm’. Through analyses of British...

  4. PROXIMATE AND ELEMENTAL COMPOSITION OF WHITE GRUBS

    African Journals Online (AJOL)

    DR. AMINU

    This study determined the proximate and mineral element composition of whole white grubs using standard methods of analysis. ... and 12.75 ± 3.65% respectively. Mineral contents of white grub in terms of relative concentration .... of intracellular Ca, bone mineralization, blood coagulation, and plasma membrane potential ...

  5. Conversion of Biowaste Asian Hard Clam (Meretrix lusoria) Shells into White-Emitting Phosphors for Use in Neutral White LEDs.

    Science.gov (United States)

    Chang, Tsung-Yuan; Wang, Chih-Min; Lin, Tai-Yuan; Lin, Hsiu-Mei

    2016-12-02

    The increasing volume and complexity of waste associated with the modern economy poses a serious risk to ecosystems and human health. However, the remanufacturing and recycling of waste into usable products can lead to substantial resource savings. In the present study, clam shell waste was first transformed into pure and well-crystallized single-phase white light-emitting phosphor Ca₉Gd(PO₄)₇:Eu 2+ ,Mn 2+ materials. The phosphor Ca₉Gd(PO₄)₇:Eu 2+ ,Mn 2+ materials were synthesized by the solid-state reaction method and the carbothermic reduction process, and then characterized and analyzed by means of X-ray diffraction (XRD) and photoluminescence (PL) measurements. The structural and luminescent properties of the phosphors were investigated as well. The PL and quantum efficiency measurements showed that the luminescence properties of clam shell-based phosphors were comparable to that of the chemically derived phosphors. Moreover, white light-emitting diodes were fabricated through the integration of 380 nm chips and single-phase white light-emitting phosphors (Ca 0.979 Eu 0.006 Mn 0.015 )₉Gd(PO₄)₇ into a single package of a white light emitting diode (WLED) emitting a neutral white light of 5298 K with color coordinates of (0.337, 0.344).

  6. Conversion of Biowaste Asian Hard Clam (Meretrix lusoria Shells into White-Emitting Phosphors for Use in Neutral White LEDs

    Directory of Open Access Journals (Sweden)

    Tsung-Yuan Chang

    2016-12-01

    Full Text Available The increasing volume and complexity of waste associated with the modern economy poses a serious risk to ecosystems and human health. However, the remanufacturing and recycling of waste into usable products can lead to substantial resource savings. In the present study, clam shell waste was first transformed into pure and well-crystallized single-phase white light-emitting phosphor Ca9Gd(PO47:Eu2+,Mn2+ materials. The phosphor Ca9Gd(PO47:Eu2+,Mn2+ materials were synthesized by the solid-state reaction method and the carbothermic reduction process, and then characterized and analyzed by means of X-ray diffraction (XRD and photoluminescence (PL measurements. The structural and luminescent properties of the phosphors were investigated as well. The PL and quantum efficiency measurements showed that the luminescence properties of clam shell-based phosphors were comparable to that of the chemically derived phosphors. Moreover, white light-emitting diodes were fabricated through the integration of 380 nm chips and single-phase white light-emitting phosphors (Ca0.979Eu0.006Mn0.0159Gd(PO47 into a single package of a white light emitting diode (WLED emitting a neutral white light of 5298 K with color coordinates of (0.337, 0.344.

  7. Magnetic white dwarfs: Observations, theory and future prospects

    Science.gov (United States)

    García-Berro, Enrique; Kilic, Mukremin; Kepler, Souza Oliveira

    2016-01-01

    Isolated magnetic white dwarfs have field strengths ranging from 103G to 109G, and constitute an interesting class of objects. The origin of the magnetic field is still the subject of a hot debate. Whether these fields are fossil, hence the remnants of original weak magnetic fields amplified during the course of the evolution of the progenitor of white dwarfs, or on the contrary, are the result of binary interactions or, finally, other physical mechanisms that could produce such large magnetic fields during the evolution of the white dwarf itself, remains to be elucidated. In this work, we review the current status and paradigms of magnetic fields in white dwarfs, from both the theoretical and observational points of view.

  8. White light-emitting diodes (LEDs) using (oxy)nitride phosphors

    International Nuclear Information System (INIS)

    Xie, R-J; Hirosaki, N; Sakuma, K; Kimura, N

    2008-01-01

    (Oxy)nitride phosphors have attracted great attention recently because they are promising luminescent materials for phosphor-converted white light-emitting diodes (LEDs). This paper reports the luminescent properties of (oxy)nitride phosphors in the system of M-Si-Al-O-N (M = Li, Ca or Sr), and optical properties of white LEDs using a GaN-based blue LED and (oxy)nitride phosphors. The phosphors show high conversion efficiency of blue light, suitable emission colours and small thermal quenching. The bichromatic white LEDs exhibit high luminous efficacy (∼55 lm W -1 ) and the multi-phosphor converted white LEDs show high colour rendering index (Ra 82-95). The results indicate that (oxy)nitride phosphors demonstrate their superior suitability to use as down-conversion luminescent materials in white LEDs

  9. Weakener of white (Wow), a gene that modifies the expression of the white eye color locus and that suppresses position effect variegation in Drosophila melanogaster.

    Science.gov (United States)

    Birchler, J A; Bhadra, U; Rabinow, L; Linsk, R; Nguyen-Huynh, A T

    1994-08-01

    A locus is described in Drosophila melanogaster that modifies the expression of the white eye color gene. This trans-acting modifier reduces the expression of the white gene in the eye, but elevates the expression in other adult tissues. Because of the eye phenotype in which the expression of white is lessened but not eliminated, the newly described locus is called the Weakener of white (Wow). Northern analysis reveals that Wow can exert an inverse or direct modifying effect depending upon the developmental stage. Two related genes, brown and scarlet, that are coordinately expressed with white, are also affected by Wow. In addition, Wow modulates the steady state RNA level of the retrotransposon, copia. When tested with a white promoter-Alcohol dehydrogenase reporter. Wow confers the modifying effect to the reporter, suggesting a requirement of the white regulatory sequences for mediating the response. In addition to being a dosage sensitive regulator of white, brown, scarlet and copia, Wow acts as a suppressor of position effect variegation. There are many dosage sensitive suppressors of position effect variegation and many dosage-sensitive modifiers of gene expression. The Wow mutations provide evidence for an overlap between the two types of modifiers.

  10. Duodenal White Spots Mimicking Intestinal Candidiasis: Report of Case

    Directory of Open Access Journals (Sweden)

    Ozgur Turk

    2015-12-01

    Full Text Available Duodenal white spots are mentioned in these nonspecific lesions until recently. Although there is not enough studies about duedonal white spots yet; these lesions described in a separate syndrome. Here now we reported a case that we diagnosed multiple Duodenal white spots mimicking intestinal candidiasis. Clinical manifestation and endoscopic appearance of lesions gave rise to thought intestinal candidiasis histopathological examination revealed us several duodenitis. There was no evidence of fungal infection in PAS staining. Early after endoscopy patient took treatment of Lansoprozole at the 30 mg dose and bismuth salicylate. Patients compliant declined and control endoscopy exposed white duodenal spots cleared away three months later. Duodenal white spots are becoming to be designated as a separate disease even a syndrome. Etiology of duodenal white spots must be determined carefully during endoscopy. Sometimes it is difficult to make the correct diagnosis by appearance of lesion; in such cases histopathological examination can be useful both differential diagnosis of disease and determination of etiological factor. [J Contemp Med 2015; 5(4.000: 249-252

  11. Greening of the White House: Six year report; TOPICAL

    International Nuclear Information System (INIS)

    None

    1999-01-01

    The White House, which recently celebrated its 200th birthday, has a long tradition of demonstrating technological innovation. In keeping with that tradition, President Clinton announced the Greening of the White House Initiative on Earth Day 1993. The initiative improves the energy and environmental performance of the White House complex by identifying opportunities to reduce waste, lower energy use, and make an appropriate use of renewable resources, all while improving indoor air quality and building comfort. This report on President Clinton's legacy of greening at the White House summarizes progress made to date and gives an overview of new opportunities identified during the past year. It also includes an environmental history of the White House and a short tour of the buildings that make up the White House complex. Over the past five years, this initiative has involved hundreds of dedicated people from both within and outside government. A description of how they worked together to develop and implement the Greening Plan is also included in this report

  12. Infrared spectrum of an extremely cool white-dwarf star

    Science.gov (United States)

    Hodgkin; Oppenheimer; Hambly; Jameson; Smartt; Steele

    2000-01-06

    White dwarfs are the remnant cores of stars that initially had masses of less than 8 solar masses. They cool gradually over billions of years, and have been suggested to make up much of the 'dark matter' in the halo of the Milky Way. But extremely cool white dwarfs have proved difficult to detect, owing to both their faintness and their anticipated similarity in colour to other classes of dwarf stars. Recent improved models indicate that white dwarfs are much more blue than previously supposed, suggesting that the earlier searches may have been looking for the wrong kinds of objects. Here we report an infrared spectrum of an extremely cool white dwarf that is consistent with the new models. We determine the star's temperature to be 3,500 +/- 200 K, making it the coolest known white dwarf. The kinematics of this star indicate that it is in the halo of the Milky Way, and the density of such objects implied by the serendipitous discovery of this star is consistent with white dwarfs dominating the dark matter in the halo.

  13. A Drosophila melanogaster hobo-white + vector mediates low frequency gene transfer in D. vlrllls with full Interspecific white + complementation

    Science.gov (United States)

    Transformation of a Drosophila virilis white mutant host strain was attempted by using a hobo vector containing the D. melanogaster mini-white+ cassette (H[w+, hawN]) and an unmodified or heat shock regulated hobo transposase helper. Two transformant lines were recovered with the unmodified helper (...

  14. High-efficiency white OLEDs based on small molecules

    Science.gov (United States)

    Hatwar, Tukaram K.; Spindler, Jeffrey P.; Ricks, M. L.; Young, Ralph H.; Hamada, Yuuhiko; Saito, N.; Mameno, Kazunobu; Nishikawa, Ryuji; Takahashi, Hisakazu; Rajeswaran, G.

    2004-02-01

    Eastman Kodak Company and SANYO Electric Co., Ltd. recently demonstrated a 15" full-color, organic light-emitting diode display (OLED) using a high-efficiency white emitter combined with a color-filter array. Although useful for display applications, white emission from organic structures is also under consideration for other applications, such as solid-state lighting, where high efficiency and good color rendition are important. By incorporating adjacent blue and orange emitting layers in a multi-layer structure, highly efficient, stable white emission has been attained. With suitable host and dopant combinations, a luminance yield of 20 cd/A and efficiency of 8 lm/W have been achieved at a drive voltage of less than 8 volts and luminance level of 1000 cd/m2. The estimated external efficiency of this device is 6.3% and a high level of operational stability is observed. To our knowledge, this is the highest performance reported so far for white organic electroluminescent devices. We will review white OLED technology and discuss the fabrication and operating characteristics of these devices.

  15. Trials to improve the response of Orechromis niloticus to Aeromonas ...

    African Journals Online (AJOL)

    sony

    2016-05-25

    May 25, 2016 ... 1 x 109 Saccharomyces cervisiae dried cells according to the manufacturers. The tested ..... Studies on the role of lymphoid organs in the antibody ... or combined, on gilthead seabream cellular innate immune. Fish. Shellfish ...

  16. UN-EDITED VERSION

    Indian Academy of Sciences (India)

    27

    effect of temperature on sex determination, differentiation and sex ratio. At ambient ... in body size (Alvarez and Nicieza 2002; Bellakhal et al. 2014; Harkey ...... expression in the brain-pituitary-gonadal axis in female red seabream during the.

  17. White Kids: Language, Race, and Styles of Youth Identity

    Science.gov (United States)

    Bucholtz, Mary

    2011-01-01

    In White Kids, Mary Bucholtz investigates how white teenagers use language to display identities based on race and youth culture. Focusing on three youth styles--preppies, hip hop fans, and nerds--Bucholtz shows how white youth use a wealth of linguistic resources, from social labels to slang, from Valley Girl speech to African American English,…

  18. White pines, blister rust, and management in the Southwest

    Science.gov (United States)

    D. A. Conklin; M Fairweather; D Ryerson; B Geils; D Vogler

    2009-01-01

    White pines in New Mexico and Arizona are threatened by the invasive disease white pine blister rust, Cronartium ribicola. Blister rust is already causing severe damage to a large population of southwestern white pine in the Sacramento Mountains of southern New Mexico. Recent detection in northern and western New Mexico suggests that a major expansion of the...

  19. White pine blister rust in the interior Mountain West

    Science.gov (United States)

    Kelly Burns; Jim Blodgett; Dave Conklin; Brian Geils; Jim Hoffman; Marcus Jackson; William Jacobi; Holly Kearns; Anna Schoettle

    2010-01-01

    White pine blister rust is an exotic, invasive disease of white, stone, and foxtail pines (also referred to as white pines or five-needle pines) in the genus Pinus and subgenus Strobus (Price and others 1998). Cronartium ribicola, the fungus that causes WPBR, requires an alternate host - currants and gooseberries in the genus Ribes and species of Pedicularis...

  20. Complexity in White Noise Analysis

    Science.gov (United States)

    Hida, Takeyuki

    We restrict our attention to random complex systems and discuss degree their degree of complexity based on a white noise. The white noise is realized as the time derivative of a Brownian motion B(t), and denoted by Ḃ(t). The collection {Ḃ(t)}, is a system of idealized elementary variables and at the same time the system is a stochastic representation of the time t, in other words it is time-oriented. Having expressed the given evolutional random phenomena in question in terms of the Ḃ(t), we introduce the notion of spectral multiplicity, which describes how much the phenomena are complex. The multiplicity is the number of cyclic subspaces that are spanned by the given random phenomena. Each cyclic subspace has further structure. Typical property is multiple Markov property, although this property appears only particular cases. As a related property, in fact as a characteristic of a complex system, one can speak of the time reversibility and irreversibility of certain random phenomena in terms of the white noise. We expect an irreversible random complex system may be decomposed into reversible systems.

  1. Mass-Accretion effects on white dwarf interiors

    International Nuclear Information System (INIS)

    Canal, R.; Hernanz, M.; Isern, J.; Labay, J.; Mochkovitch, R.

    1986-01-01

    There is observational evidence of the presence of young neutron stars in old binary systems. A likely explanation is that those neutron stars were produced in the collapse of old C+O white dwarfs. Old white dwarfs being cold and at least partially solid, accretion-induced mass growth should finally lead in a number of cases, to their collapse rather than to their explosion. We show in detail how mass accretion on initially solid white dwarfs can leave central solid cores when dynamical instability sets in. We also study the different effects of the existence of such cores on the outcome of the competition between thermonuclear explosion and gravitational collapse

  2. Convective mixing and accretion in white dwarfs

    International Nuclear Information System (INIS)

    Koester, D.

    1976-01-01

    The evolution of convection zones in cooling white dwarfs with helium envelopes and outer hydrogen layers is calculated with a complete stellar evolution code. It is shown that white dwarfs of spectral type DB cannot be formed from DA stars by convective mixing. However, for cooler temperatures (Tsub(e) [de

  3. 77 FR 66351 - Establishing the White House Homeland Security Partnership Council

    Science.gov (United States)

    2012-11-02

    ... the White House Homeland Security Partnership Council #0; #0; #0; Presidential Documents #0; #0; #0;#0... White House Homeland Security Partnership Council By the authority vested in me as President by the... States. Sec. 2. White House Homeland Security Partnership Council and Steering Committee. (a) White House...

  4. Red wines good, white wines bad?

    International Nuclear Information System (INIS)

    Van Velden, D.P.; Mansvelt, E.P.G.; Troup, G.J.

    2002-01-01

    Full text: In 1994, free radicals were discovered in red wines, but only in whites exposed to skins and seeds, and/or oak. The radicals are on the phenolics, and therefore a measure of phenolic content. In 1995, Fuhrman, Levy and Aviram published a study showing antioxidant effects of red wine in the standard Israeli diet, but pro-oxidant effects of the white wine used. No phenolic analysis was done, but low or no phenolics were suspected. Letters to the winery used by Aviram proved fruitless. In 2001, Aviram admits that to see a significant antioxidant effect from white wine, he must make his own, giving it skin and seed contact, and adding alcohol to the fermenting stage, to leach out more tannin from the seeds. This would be unsaleable as a table wine, but not as a 'fortified' or 'dessert' wine. A completely independent study by van Velden in South Africa, with phenol analysis of wines, shows pro- oxidant behaviour of white wines low or lacking in phenolic content. This will be summarised. A Japanese study of the antioxidant properties of some wines shows none for wines low or lacking in catechin content. In the 1950's, two similar but independent studies on different laboratory animals showed no ill effects from 10% alcohol red wine in their diet, but serious effects from 10% pure alcohol - water mix. Conclusion. Drinking only of white wines lacking in phenols, either due to 'fining', or to deliberate avoidance in making, at the recommended 'moderate' drinking level, may be deleterious to cardiovascular health, because of their pro-oxidant action, now established

  5. 78 FR 18989 - Ryan White HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV...

    Science.gov (United States)

    2013-03-28

    ... HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV/AIDS Program.... ACTION: Notice of Ryan White HIV/AIDS Program Part C Early Intervention Services One-Time Noncompetitive... care services for persons living with HIV/AIDS, HRSA will provide a one-time noncompetitive Part C...

  6. 78 FR 10182 - Ryan White HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV...

    Science.gov (United States)

    2013-02-13

    ... HIV/AIDS Program, Part C Early Intervention Services Grant Under the Ryan White HIV/AIDS Program.... ACTION: Notice of Ryan White HIV/AIDS Program (Part C) Early Intervention Services One-Time... primary care services for persons living with HIV/AIDS, HRSA will provide one-time noncompetitive Part C...

  7. Cortex Parcellation Associated Whole White Matter Parcellation in Individual Subjects

    Directory of Open Access Journals (Sweden)

    Patrick Schiffler

    2017-07-01

    Full Text Available The investigation of specific white matter areas is a growing field in neurological research and is typically achieved through the use of atlases. However, the definition of anatomically based regions remains challenging for the white matter and thus hinders region-specific analysis in individual subjects. In this article, we focus on creating a whole white matter parcellation method for individual subjects where these areas can be associated to cortex regions. This is done by combining cortex parcellation and fiber tracking data. By tracking fibers out of each cortex region and labeling the fibers according to their origin, we populate a candidate image. We then derive the white matter parcellation by classifying each white matter voxel according to the distribution of labels in the corresponding voxel from the candidate image. The parcellation of the white matter with the presented method is highly reliable and is not as dependent on registration as with white matter atlases. This method allows for the parcellation of the whole white matter into individual cortex region associated areas and, therefore, associates white matter alterations to cortex regions. In addition, we compare the results from the presented method to existing atlases. The areas generated by the presented method are not as sharply defined as the areas in most existing atlases; however, they are computed directly in the DWI space of the subject and, therefore, do not suffer from distortion caused by registration. The presented approach might be a promising tool for clinical and basic research to investigate modalities or system specific micro structural alterations of white matter areas in a quantitative manner.

  8. White matter abnormalities of microstructure and physiological noise in schizophrenia.

    Science.gov (United States)

    Cheng, Hu; Newman, Sharlene D; Kent, Jerillyn S; Bolbecker, Amanda; Klaunig, Mallory J; O'Donnell, Brian F; Puce, Aina; Hetrick, William P

    2015-12-01

    White matter abnormalities in schizophrenia have been revealed by many imaging techniques and analysis methods. One of the findings by diffusion tensor imaging is a decrease in fractional anisotropy (FA), which is an indicator of white matter integrity. On the other hand, elevation of metabolic rate in white matter was observed from positron emission tomography (PET) studies. In this report, we aim to compare the two structural and functional effects on the same subjects. Our comparison is based on the hypothesis that signal fluctuation in white matter is associated with white matter functional activity. We examined the variance of the signal in resting state fMRI and found significant differences between individuals with schizophrenia and non-psychiatric controls specifically in white matter tissue. Controls showed higher temporal signal-to-noise ratios clustered in regions including temporal, frontal, and parietal lobes, cerebellum, corpus callosum, superior longitudinal fasciculus, and other major white matter tracts. These regions with higher temporal signal-to-noise ratio agree well with those showing higher metabolic activity reported by studies using PET. The results suggest that individuals with schizophrenia tend to have higher functional activity in white matter in certain brain regions relative to healthy controls. Despite some overlaps, the distinct regions for physiological noise are different from those for FA derived from diffusion tensor imaging, and therefore provide a unique angle to explore potential mechanisms to white matter abnormality.

  9. White piedra: further evidence of a synergistic infection.

    Science.gov (United States)

    Youker, Summer R; Andreozzi, Robert J; Appelbaum, Peter C; Credito, Kim; Miller, Jeffrey J

    2003-10-01

    White piedra is a fungal infection of the hair shaft caused by Trichosporon beigelii. A synergistic coryneform bacterial infection is often present with T beigelii. White piedra, although not commonly reported to infect scalp hair in North America, is an important consideration in the differential diagnosis of scalp hair concretions. We report a case of white piedra of scalp hair with synergistic coryneform bacterial infection in two sisters, both US natives. Culture and light and electronmicroscopic evidence of the synergistic infection are presented.

  10. White House Communications Agency

    National Research Council Canada - National Science Library

    Gimble, Thomas

    1995-01-01

    ...; and the Deputy Secretary of Defense requested the audit. The Deputy Secretary of Defense emphasized that this review should be as thorough as possible of all White House Communications Agency (WHCA...

  11. White dwarfs, the galaxy and Dirac's cosmology

    International Nuclear Information System (INIS)

    Stothers, R.

    1976-01-01

    Reference is made to the apparent absence, or deficiency, of white dwarfs fainter than about 10 -4 L solar mass. An explanation is here proposed on the basis of Dirac's cosmological hypothesis that the gravitational constant, G, has varied with the time elapsed since the beginning of the expansion of the Universe as t -1 and the number of particles in the Universe has increases as t 2 , if the measurements are made in atomic units. For a white dwarf the Chandrasekhar mass limit is a collection of fundamental constants proportional to Gsup(-3/2) and therefore increases with time as tsup(3/2). In the 'additive' version of Dirac's theory the actual mass, M, of a relatively small object like a star remains essentially unchanged by the creation of new matter in the Universe and hence a white dwarf will become more stable with the course of time; but in the 'multiplicative' version of the theory, M increases as t 2 and may eventually exceed the Chandrasekhar limit, and if this happens, gravitational collapse of the white dwarf into an invisible black hole or neutron star will quickly occur. It is considered interesting to find whether the 'multiplicative' theory may have a bearing on the apparent deficiency of faint white dwarfs, and to consider whether there are any possible consequences for galactic evolution. This is here discussed. (U.K.)

  12. Maximum gravitational redshift of white dwarfs

    International Nuclear Information System (INIS)

    Shapiro, S.L.; Teukolsky, S.A.

    1976-01-01

    The stability of uniformly rotating, cold white dwarfs is examined in the framework of the Parametrized Post-Newtonian (PPN) formalism of Will and Nordtvedt. The maximum central density and gravitational redshift of a white dwarf are determined as functions of five of the nine PPN parameters (γ, β, zeta 2 , zeta 3 , and zeta 4 ), the total angular momentum J, and the composition of the star. General relativity predicts that the maximum redshifts is 571 km s -1 for nonrotating carbon and helium dwarfs, but is lower for stars composed of heavier nuclei. Uniform rotation can increase the maximum redshift to 647 km s -1 for carbon stars (the neutronization limit) and to 893 km s -1 for helium stars (the uniform rotation limit). The redshift distribution of a larger sample of white dwarfs may help determine the composition of their cores

  13. White-centred retinal haemorrhages (Roth spots).

    OpenAIRE

    Ling, R.; James, B.

    1998-01-01

    Roth spots (white-centred retinal haemorrhages) were classically described as septic emboli lodged in the retina of patients with subacute bacterial endocarditis. Indeed many have considered Roth spots pathognomonic for this condition. More recent histological evidence suggests, however, that they are not foci of bacterial abscess. Instead, they are nonspecific and may be found in many other diseases. A review of the histology and the pathogenesis of these white-centred haemorrhages will be p...

  14. A genome-wide scan study identifies a single nucleotide substitution in ASIP associated with white versus non-white coat-colour variation in sheep (Ovis aries).

    Science.gov (United States)

    Li, M-H; Tiirikka, T; Kantanen, J

    2014-02-01

    In sheep, coat colour (and pattern) is one of the important traits of great biological, economic and social importance. However, the genetics of sheep coat colour has not yet been fully clarified. We conducted a genome-wide association study of sheep coat colours by genotyping 47 303 single-nucleotide polymorphisms (SNPs) in the Finnsheep population in Finland. We identified 35 SNPs associated with all the coat colours studied, which cover genomic regions encompassing three known pigmentation genes (TYRP1, ASIP and MITF) in sheep. Eighteen of these associations were confirmed in further tests between white versus non-white individuals, but none of the 35 associations were significant in the analysis of only non-white colours. Across the tests, the s66432.1 in ASIP showed significant association (P=4.2 × 10(-11) for all the colours; P=2.3 × 10(-11) for white versus non-white colours) with the variation in coat colours and strong linkage disequilibrium with other significant variants surrounding the ASIP gene. The signals detected around the ASIP gene were explained by differences in white versus non-white alleles. Further, a genome scan for selection for white coat pigmentation identified a strong and striking selection signal spanning ASIP. Our study identified the main candidate gene for the coat colour variation between white and non-white as ASIP, an autosomal gene that has been directly implicated in the pathway regulating melanogenesis. Together with ASIP, the two other newly identified genes (TYRP1 and MITF) in the Finnsheep, bordering associated SNPs, represent a new resource for enriching sheep coat-colour genetics and breeding.

  15. "The normative idea of queer is a white person": understanding perceptions of white privilege among lesbian, bisexual, and queer women of color in Toronto, Canada.

    Science.gov (United States)

    Logie, Carmen H; Rwigema, Marie-Jolie

    2014-01-01

    White privilege constructs whiteness as normative and central to lesbian, gay, bisexual, and queer (LGBQ) identities and is reproduced through social norms, media representations, and daily interactions. We aimed to enhance understanding of the processes by which white privilege was experienced among lesbian, bisexual, and queer (LBQ) women of color in Toronto, Canada. We conducted two focus groups with LBQ women of color, one with participants who self-identified as masculine of center (n = 8) and the second with participants who identified as feminine of center (n = 8). Findings indicate that LBQ women of color experience intersectional stigma (e.g., homophobia, racism, sexism) on a daily basis. Participant narratives revealed that white privilege shaped the representations of women of color in a particular way that promoted their exclusion from white LBQ spaces and broader society. By representing queerness as white, LBQ women of color were rendered invisible in both queer and racialized communities. LBQ women of color were further marginalized by constructions of "real" women as passive, feminine and white, and conversely perceptions of women of color as aggressive, emotional, and hypersexualized. These representations inform spatialized practices and social interactions through constructing racialized communities as discriminatory and "backwards" while maintaining the invisibility of white privilege and racism in LBQ spaces.

  16. The White Mountain Recreational Enterprise: Bio-Political Foundations for White Mountain Apache Natural Resource Control, 1945–1960

    Directory of Open Access Journals (Sweden)

    David C. Tomblin

    2016-07-01

    Full Text Available Among American Indian nations, the White Mountain Apache Tribe has been at the forefront of a struggle to control natural resource management within reservation boundaries. In 1952, they developed the first comprehensive tribal natural resource management program, the White Mountain Recreational Enterprise (WMRE, which became a cornerstone for fighting legal battles over the tribe’s right to manage cultural and natural resources on the reservation for the benefit of the tribal community rather than outside interests. This article examines how White Mountain Apaches used the WMRE, while embracing both Euro-American and Apache traditions, as an institutional foundation for resistance and exchange with Euro-American society so as to reassert control over tribal eco-cultural resources in east-central Arizona.

  17. MR imaging of white-matter diseases in children

    International Nuclear Information System (INIS)

    Sato, Y.; Yuh, W.T.C.; Mathews, K.; Wiese, J.; Kao, S.; Schreiber, A.; Farner, R.; Smith, W.

    1987-01-01

    MR imaging has become a valuable tool in the investigation of central nervous system abnormalities in children. This exhibit displays the MR imaging patterns in 30 children with diseases involving the white matter. Clinical, CT, and pathologic findings will be presented for comparison. The white matter disease entities studies include acquired white matter diseases, metabolic diseases, and phycomatoses. Specific examples include acute dissemination encephalomyelitis, anoxic encephalopathy, disseminated necrotizing leukoencephalopathy, demyelinating adrenoleukodystrophy, Krabbe disease, metachromatic leukodystrophy, Tay-Sachs disease, Gaucher disease, neurofibromatosis, and Sturge-Weber syndrome

  18. [Health impact assessment of "white-collar exemption" in Japan].

    Science.gov (United States)

    Fujino, Yoshihisa; Matsuda, Shinya

    2007-03-01

    This work conducted a health impact assessment (HIA) of the Japanese Government's proposal concerning the introduction of so called "white-collar exemption" into the Japanese labor market. We adopted the Merseyside model and performed a rapid health impact assessment to assess the potential health effects of white-collar exemption. In this HIA, several health determinants which may possibly be affected, both positively and negatively, were identified based on experts' judgments. Literature evidence was assessed using PubMed and other databases. In addition, we searched for the opinions of those affected by white-collar exemption from internet web sites, and six concerns were identified. Long working hours were identified as the most serious concern by both experts and those affected. White-collar exemption may increase irregular working patterns which may be related to sleep disorder, stress, and cardiovascular disease. Family function and social participation will also be affected by irregular working patterns. On the other hand, in terms of stress, white-collar exemption may benefit from a higher degree of job control. There are possibilities that white-collar exemption may enable an improved work-life balance and enable access of some groups of the population, such as people with disabilities or parents looking after children, greater access to the labour market. However, it is uncertain whether the benefits of white-collar exemption would overcome those of the current free-time or flex-time systems. The present work provides a wide range of health impacts of white-collar exemption, and will hopefully attract the attentions of decision-makers and those likely to be affected in order to contribute to policy-making.

  19. Lanthanum deposition corresponds to white lesions in the stomach.

    Science.gov (United States)

    Iwamuro, Masaya; Urata, Haruo; Tanaka, Takehiro; Kawano, Seiji; Kawahara, Yoshiro; Kimoto, Katsuhiko; Okada, Hiroyuki

    2018-05-23

    Although lanthanum deposition in the stomach has been most frequently reported to occur as white lesions, no study has investigated whether the white lesions observed during esophagogastroduodenoscopy are truly lanthanum-related. Here, we retrospectively investigated the amount of lanthanum in endoscopic biopsy specimens. We reviewed four patients showing gastric white spots or annular whitish mucosa in the gastric white lesions (Bw) and peripheral mucosa where the white substance was not endoscopically observed (Bp) during biopsy. We also reviewed three patients with diffuse whitish mucosa and three patients with no whitish lesions. We performed scanning electron microscopy and energy dispersive X-ray spectrometry to quantify the lanthanum elements (wt%) in the biopsy specimens. The amount of lanthanum in the Bw ranged from 0.15-0.31 wt%, whereas that of Bp was 0.00-0.13 wt%. The difference was statistically significant (P < 0.05). The amount of lanthanum in the Bw, endoscopically presented with white spots or annular whitish mucosa, was significantly higher than that of no whitish lesions (0.05-0.14 wt%, P < 0.05). The amount of lanthanum was also higher in the diffuse whitish mucosa (0.21-0.23 wt%) compared with no whitish lesions (P < 0.01). This study is the first to reveal that pathological lanthanum deposition corresponds to the endoscopically observed white lesions in the gastric mucosa. Therefore, during esophagogastroduodenoscopy, physicians should pay attention to possible presence of white lesions in patients treated with oral lanthanum carbonate to ensure prompt identification of associated issues. Copyright © 2018 Elsevier GmbH. All rights reserved.

  20. Know History, Know Self: Art Therapists' Responsibility to Dismantle White Supremacy

    Science.gov (United States)

    Hamrick, Cassie; Byma, Christine

    2017-01-01

    In this article, we call on white art therapists to assume responsibility for dismantling white supremacy in the field of art therapy, in personal as well as political-structural arenas. We respond to calls from scholars and writers of color for white people to assume increased responsibility for dismantling white supremacy in white communities…

  1. House sparrows benefit from the conservation of white storks

    Science.gov (United States)

    Kosicki, Jakub Z.; Sparks, Tim H.; Tryjanowski, Piotr

    2007-05-01

    As with many farmland bird species, the house sparrow Passer domesticus is declining in Europe, mainly due to intensification of agriculture reducing nest sites and food supplies. During 2002-2005, we studied the population size and nest site characteristics of house sparrows breeding within white stork Ciconia ciconia nests in a large area of agricultural landscape within western Poland. To explain sparrow density within stork nests, we examined characteristics of white stork nests (position, age, productivity) and the farm type around the nest. House sparrow density was greatest in the longest established (and hence larger) white stork nests located on traditionally managed farms. Two recent changes appear to have adverse effects on house sparrows. The first is the intensification of farming and the second is active management of white stork nests on electric poles to reduce nest size and thus avoid both disruption to the electrical supply and electrocution of white storks. Because the white stork has such a high profile in Poland, there are numerous schemes to conserve and enhance this species. In conclusion, we clearly show that protecting one species can have valuable, although unplanned, benefits to another species of conservation interest, the house sparrow.

  2. Proton beam modification of lead white pigments

    International Nuclear Information System (INIS)

    Beck, L.; Gutiérrez, P.C.; Miserque, F.; Thomé, L.

    2013-01-01

    Pigments and paint materials are known to be sensitive to particle irradiation. Occasionally, the analysis of paintings by PIXE can induce a slight or dark stain depending on the experimental conditions (beam current, dose, particle energy). In order to understand this discoloration, we have irradiated various types of art white pigments – lead white (hydrocerussite and basic lead sulfate), gypsum, calcite, zinc oxide and titanium oxide – with an external 3 MeV proton micro-beam commonly used for PIXE experiments. We have observed various sensitivities depending on the pigment. No visible change occurs for calcite and titanium oxide, whereas lead white pigments are very sensitive. For the majority of the studied compounds, the discoloration is proportional to the beam current and charge. The damage induced by proton beam irradiation in lead white pigments was studied by micro-Raman and XPS spectroscopies. Structural modifications and dehydration were detected. Damage recovery was investigated by thermal treatment and UV-light irradiation. The discoloration disappeared after one week of UV illumination, showing that PIXE experiments could be safely undertaken for pigments and paintings

  3. Trump Voters and the White Working Class

    Directory of Open Access Journals (Sweden)

    Stephen L. Morgan

    2018-04-01

    Full Text Available To evaluate the claim that white working-class voters were a crucial block of support for Trump in the 2016 presidential election, this article offers two sets of results. First, self-reports of presidential votes in 2012 and 2016 from the American National Election Studies show that Obama-to-Trump voters and 2012 eligible nonvoters composed a substantial share of Trump’s 2016 voters and were disproportionately likely to be members of the white working class. Second, when county vote tallies in 2012 and 2016 are merged with the public-use microdata samples of the 2012-to-2016 American Community Surveys, areal variations across 1,142 geographic units that sensibly partition the United States show that Trump’s gains in 2016 above Romney’s performance in 2012 are strongly related to the proportion of the voting population in each area that was white and working class. Taken together, these results support the claim that Trump’s appeal to the white working class was crucial for his victory.

  4. Temperatures and luminosities of white dwarfs in dwarf novae

    International Nuclear Information System (INIS)

    Smak, J.

    1984-01-01

    Far ultraviolet radiation observed in dwarf novae at minimum can only be attributed to their white dwarfs. In three systems white dwarfs are detected directly through their eclipses. These data are used to determine the effective temperatures and luminosities of white dwarfs. The resulting temperatures range from about logT e = 4.1 to about 4.9, with typical values of about 4.5. The luminosities range from about logL 1 = 31.0 to about 33.5 and show correlation with the average accretion rates. Radiation from white dwarfs is likely to be the source of excitation of the emission lines from disks. It is also argued that the heating by the white dwarf can significantly modify the structure of the innermost parts of the disk and, particularly, inhibit the incidence of thermal instability in that region. 26 refs., 2 figs., 1 tab. (author)

  5. White certificate: how to launch the system?

    International Nuclear Information System (INIS)

    2005-01-01

    White certificates are a supple and suitable economical system for the quest of diffuse energy saving. It relies on the energy distribution networks and is complementary to other existing system (fiscality, regulation, etc). It is an open system, based on a market logics in order to make energy savings where they are the less costly. This document gathers the synthesis of the conference about white certificates, held in Paris in October 2005, the presentations (transparencies) given by J. Percebois (Creden) about the French system of energy savings and by P. Guyonnet (ATEE) about the way to launch the system of white certificates. The debate with the audience is also reported. (J.S.)

  6. Histopathology confirms white-nose syndrome in bats in Europe.

    Science.gov (United States)

    Pikula, Jiri; Bandouchova, Hana; Novotny, Ladislav; Meteyer, Carol U; Zukal, Jan; Irwin, Nancy R; Zima, Jan; Martínková, Natália

    2012-01-01

    White-nose syndrome, associated with the fungal skin infection geomycosis, caused regional population collapse in bats in North America. Our results, based on histopathology, show the presence of white-nose syndrome in Europe. Dermatohistopathology on two bats (Myotis myotis) found dead in March 2010 with geomycosis in the Czech Republic had characteristics resembling Geomyces destructans infection in bats confirmed with white-nose syndrome in US hibernacula. In addition, a live M. myotis, biopsied for histopathology during hibernation in April 2011, had typical fungal infection with cupping erosion and invasion of muzzle skin diagnostic for white-nose syndrome and conidiospores identical to G. destructans that were genetically confirmed as G. destructans.

  7. Extinction correction in white X-ray and neutron diffraction

    International Nuclear Information System (INIS)

    Tomiyoshi, S.; Yamada, M.; Watanabe, H.

    1980-01-01

    Extinction effects in white-beam X-ray and neutron diffraction are considered. In white-beam diffraction, a small deviation of the wavelength from the Bragg condition Δlambda is a variable which represents the line profile of the diffraction peaks, so that by using the new parameter Δlambda the theory is converted to one in white-beam diffraction. It is shown that for a convex crystal, primary extinction agrees with the results calculated already for monochromatic diffraction. The same relation is shown to hold in secondary extinction. It is concluded that extinction theory derived for monochromatic diffraction is applicable without any modification in white-beam diffraction. (Auth.)

  8. 2012 White Book, Pacific Northwest Loads and Resources Study

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-06

    The White Book is a planning analysis produced by BPA that informs BPA of its load and resource conditions for sales and purchases. The White Book provides a 10-year look at the expected obligations and resources in the Federal system and PNW region. The White Book is used as a planning tool for the Columbia River Treaty (Treaty) studies, as an information tool for customers and regional interests, and as a publication of information utilized by other planning entities for their analyses. The White Book is not used to guide day-to-day operations of the Federal Columbia River Power System (FCRPS) or determine BPA revenues or rates.

  9. Northeast Atlantic blue whiting

    OpenAIRE

    Heino, Mikko

    2010-01-01

    Heino, M. 2010. Northeast Atlantic blue whiting. In Life cycle spatial patterns of small pelagic fish in the Northeast Atlantic, pp. 59-64. Ed by P. Petitgas. ICES Cooperative Research Report 306. ICES, Copenhagen.

  10. White dwarf stars exceeding the Chandrasekhar mass limit

    Science.gov (United States)

    Tomaschitz, Roman

    2018-01-01

    The effect of nonlinear ultra-relativistic electron dispersion on the mass-radius relation of high-mass white dwarfs is studied. The dispersion is described by a permeability tensor in the Dirac equation, generated by the ionized high-density stellar matter, which constitutes the neutralizing background of the nearly degenerate electron plasma. The electron dispersion results in a stable mass-radius relation for high-mass white dwarfs, in contrast to a mass limit in the case of vacuum permeabilities. In the ultra-relativistic regime, the dispersion relation is a power law whose amplitude and scaling exponent is inferred from mass and radius estimates of two high-mass white dwarfs, Sirius B and LHS 4033. Evidence for the existence of super-Chandrasekhar mass white dwarfs is provided by several Type Ia supernovae (e.g., SN 2013cv, SN 2003fg, SN 2007if and SN 2009dc), whose mass ejecta exceed the Chandrasekhar limit by up to a factor of two. The dispersive mass-radius relation is used to estimate the radii, central densities, Fermi temperatures, bulk and compression moduli and sound velocities of their white dwarf progenitors.

  11. White piedra of scalp hair by Trichosporon inkin.

    Science.gov (United States)

    Viswanath, Vishalakshi; Kriplani, Dimple; Miskeen, Autar Kishen; Patel, Bharti; Torsekar, Raghunandan Govind

    2011-01-01

    White piedra is a rare fungal infection of hair and is reported to be all the more rare on scalp. Trichosporon inkin is usually associated with white piedra of pubic hair. We report a case of white piedra of scalp hair caused by T. inkin. This is the first case reported from India and the fifth case reported worldwide. A 50-year-old Muslim female presented with white knots over scalp hair. Diagnosis of Trichosporon was made by examining KOH mounts of epilated hair and Lactophenol Cotton Blue preparations of the growth in culture. Automated mini-API test (for biochemical profiles) and Electronmicroscopy studies (for cell wall structures) helped in identification of the species. Mini-API test was also positive for Cryptococcus curvatus which could be due to similarity in biochemical and physiological properties of the two species. Absence of C. curvatus on culture further supports this view. Topical antifungal therapy resulted in clinical clearance within 2 months. Higher incidence of scalp white piedra is observed in Muslim females; contributing factor being the custom of using a veil, leading to higher humidity and limited sunlight exposure.

  12. Histological study of white rhinoceros integument

    OpenAIRE

    Plochocki, Jeffrey H.; Ruiz, Saul; Rodriguez-Sosa, Jos? R.; Hall, Margaret I.

    2017-01-01

    In this study, we report findings from a microscopic analysis of the white rhinoceros (Ceratotherium simum) integumentary ultrastructure. Skin samples from the cheek, shoulder, flank and rump were taken from a 46-year-old female southern white rhinoceros and examined using H&E and elastic histological stains. The epidermis was thickest in the flank (1.003 mm) followed by the rump, cheek and shoulder. The stratum corneum comprised more than half the epidermal thickness. Numerous melanin granul...

  13. White Dwarfs in the HET Dark Energy Experiment

    Science.gov (United States)

    Castanheira, B. G.; Winget, D. E.; Williams, K.; Montgomery, M. H.; Falcon, R. E.; Hermes, J. J.

    2010-11-01

    In the past decades, large scale surveys have discovered a large number of white dwarfs. For example, the Sloan Digital Sky Survey (SDSS) Data Release 7 [5] lists about 20 000 spectroscopically confirmed new white dwarfs. More than just a number, the new discoveries revealed different flavors of white dwarfs, including a new class of pulsators [7] and a larger percentage of stars with a magnetic field [4]. The HET Dark Energy Experiment (HETDEX) will use the 9.2 m Hobby-Eberly Telescope at McDonald Observatory and a set of 150 spectrographs to map the three-dimensional positions of one million galaxies. The main goal of the survey is to probe dark energy by observing the recent universe (2products. We expect to obtain spectra for about 10 000 white dwarfs in the next 3 to 4 years.

  14. Doubling the number of pulsating DB white dwarfs

    International Nuclear Information System (INIS)

    Nitta, Atsuko; Kleinman, S J; Krzenski, J; Kepler, S O; Metcalfe, T S; Mukadam, Anjum S; Mullally, F; Nather, R E; Winget, D E; Sullivan, D; Thompson, Susan E

    2009-01-01

    We are searching for new pulsating DB white dwarf stars (DBVs) based on the newly found white dwarf stars from the spectra obtained by the Sloan Digital Sky Survey. DBVs pulsate at hotter temperature ranges than their better known cousins, DAVs or ZZ Ceti stars. Since the evolution of white dwarf stars is characterized by cooling, asteroseismological studies of DBVs give us opportunities to study white dwarf structure at a different evolutionary stage than the DAVs. The hottest DBVs are thought to have neutrino luminosities exceeding their photon luminosities (Winget et al. 2004), a quantity measurable through asteroseismology. Therefore, they can also be used to study neutrino physics in the stellar interior. At the time of the meeting, we reported on the nine new DBVs, doubling the number of previously known DBVs. Here we report the new nine pulsators' lightcurves and power spectra.

  15. THE POST-MERGER MAGNETIZED EVOLUTION OF WHITE DWARF BINARIES: THE DOUBLE-DEGENERATE CHANNEL OF SUB-CHANDRASEKHAR TYPE Ia SUPERNOVAE AND THE FORMATION OF MAGNETIZED WHITE DWARFS

    International Nuclear Information System (INIS)

    Ji Suoqing; Fisher, Robert T.; García-Berro, Enrique; Tzeferacos, Petros; Jordan, George; Lee, Dongwook; Lorén-Aguilar, Pablo; Cremer, Pascal; Behrends, Jan

    2013-01-01

    Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white dwarf binaries, referred to as the double-degenerate channel, as the possible progenitor systems for some SNe Ia. Additionally, recent theoretical work suggests that mergers which fail to detonate may produce magnetized, rapidly rotating white dwarfs. In this paper, we present the first multidimensional simulations of the post-merger evolution of white dwarf binaries to include the effect of the magnetic field. In these systems, the two white dwarfs complete a final merger on a dynamical timescale, and are tidally disrupted, producing a rapidly rotating white dwarf merger surrounded by a hot corona and a thick, differentially rotating disk. The disk is strongly susceptible to the magnetorotational instability (MRI), and we demonstrate that this leads to the rapid growth of an initially dynamically weak magnetic field in the disk, the spin-down of the white dwarf merger, and to the subsequent central ignition of the white dwarf merger. Additionally, these magnetized models exhibit new features not present in prior hydrodynamic studies of white dwarf mergers, including the development of MRI turbulence in the hot disk, magnetized outflows carrying a significant fraction of the disk mass, and the magnetization of the white dwarf merger to field strengths ∼2 × 10 8 G. We discuss the impact of our findings on the origins, circumstellar media, and observed properties of SNe Ia and magnetized white dwarfs

  16. The Post-merger Magnetized Evolution of White Dwarf Binaries: The Double-degenerate Channel of Sub-Chandrasekhar Type Ia Supernovae and the Formation of Magnetized White Dwarfs

    Science.gov (United States)

    Ji, Suoqing; Fisher, Robert T.; García-Berro, Enrique; Tzeferacos, Petros; Jordan, George; Lee, Dongwook; Lorén-Aguilar, Pablo; Cremer, Pascal; Behrends, Jan

    2013-08-01

    Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white dwarf binaries, referred to as the double-degenerate channel, as the possible progenitor systems for some SNe Ia. Additionally, recent theoretical work suggests that mergers which fail to detonate may produce magnetized, rapidly rotating white dwarfs. In this paper, we present the first multidimensional simulations of the post-merger evolution of white dwarf binaries to include the effect of the magnetic field. In these systems, the two white dwarfs complete a final merger on a dynamical timescale, and are tidally disrupted, producing a rapidly rotating white dwarf merger surrounded by a hot corona and a thick, differentially rotating disk. The disk is strongly susceptible to the magnetorotational instability (MRI), and we demonstrate that this leads to the rapid growth of an initially dynamically weak magnetic field in the disk, the spin-down of the white dwarf merger, and to the subsequent central ignition of the white dwarf merger. Additionally, these magnetized models exhibit new features not present in prior hydrodynamic studies of white dwarf mergers, including the development of MRI turbulence in the hot disk, magnetized outflows carrying a significant fraction of the disk mass, and the magnetization of the white dwarf merger to field strengths ~2 × 108 G. We discuss the impact of our findings on the origins, circumstellar media, and observed properties of SNe Ia and magnetized white dwarfs.

  17. THE POST-MERGER MAGNETIZED EVOLUTION OF WHITE DWARF BINARIES: THE DOUBLE-DEGENERATE CHANNEL OF SUB-CHANDRASEKHAR TYPE Ia SUPERNOVAE AND THE FORMATION OF MAGNETIZED WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Ji Suoqing; Fisher, Robert T. [University of Massachusetts Dartmouth, Department of Physics, 285 Old Westport Road, North Dartmouth, MA 02740 (United States); Garcia-Berro, Enrique [Departament de Fisica Aplicada, Universitat Politecnica de Catalunya, c/Esteve Terrades, 5, E-08860 Castelldefels (Spain); Tzeferacos, Petros; Jordan, George; Lee, Dongwook [Center for Astrophysical Thermonuclear Flashes, The University of Chicago, Chicago, IL 60637 (United States); Loren-Aguilar, Pablo [School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Cremer, Pascal [Bethe Center for Theoretical Physics, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Behrends, Jan [Fachbereich Physik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin (Germany)

    2013-08-20

    Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white dwarf binaries, referred to as the double-degenerate channel, as the possible progenitor systems for some SNe Ia. Additionally, recent theoretical work suggests that mergers which fail to detonate may produce magnetized, rapidly rotating white dwarfs. In this paper, we present the first multidimensional simulations of the post-merger evolution of white dwarf binaries to include the effect of the magnetic field. In these systems, the two white dwarfs complete a final merger on a dynamical timescale, and are tidally disrupted, producing a rapidly rotating white dwarf merger surrounded by a hot corona and a thick, differentially rotating disk. The disk is strongly susceptible to the magnetorotational instability (MRI), and we demonstrate that this leads to the rapid growth of an initially dynamically weak magnetic field in the disk, the spin-down of the white dwarf merger, and to the subsequent central ignition of the white dwarf merger. Additionally, these magnetized models exhibit new features not present in prior hydrodynamic studies of white dwarf mergers, including the development of MRI turbulence in the hot disk, magnetized outflows carrying a significant fraction of the disk mass, and the magnetization of the white dwarf merger to field strengths {approx}2 Multiplication-Sign 10{sup 8} G. We discuss the impact of our findings on the origins, circumstellar media, and observed properties of SNe Ia and magnetized white dwarfs.

  18. Chemical Assessment of White Wine during Fermentation Process

    Directory of Open Access Journals (Sweden)

    Teodora Coldea

    2014-05-01

    Full Text Available There were investigated chemical properties of indigenous white wine varieties (Fetească albă, Fetească regală and Galbenă de Odobeşti during fermentation. The white wine making process took place at Wine Pilot Station of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. We aimed to monitorize the evolution of fermentation process parameters (temperature, alcohol content, and real extract and the quality of the bottled white wine (total acidity, alcohol content, total sulfur dioxide, total dry extract. The results obtained were in accordance to Romanian Legislation.

  19. A SEARCH FOR ASTEROIDS, MOONS, AND RINGS ORBITING WHITE DWARFS

    International Nuclear Information System (INIS)

    Di Stefano, Rosanne; Howell, Steve B.; Kawaler, Steven D.

    2010-01-01

    Do white dwarfs host asteroid systems? Although several lines of argument suggest that white dwarfs may be orbited by large populations of asteroids, transits would provide the most direct evidence. We demonstrate that the Kepler mission has the capability to detect transits of white dwarfs by asteroids. Because white-dwarf asteroid systems, if they exist, are likely to contain many asteroids orbiting in a spatially extended distribution, discoveries of asteroid transits can be made by monitoring only a small number of white dwarfs, compatible with Kepler's primary mission, which is to monitor stars with potentially habitable planets. Possible future missions that survey 10 times as many stars with similar sensitivity and minute-cadence monitoring can establish the characteristics of asteroid systems around white dwarfs, such as the distribution of asteroid sizes and semimajor axes. Transits by planets would be more dramatic, but the probability that they will occur is lower. Ensembles of planetary moons and/or the presence of rings around planets can also produce transits detectable by Kepler. The presence of moons and rings can significantly increase the probability that Kepler will discover planets orbiting white dwarfs, even while monitoring only a small number of them.

  20. White dwarfs, the galaxy and Dirac's cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Stothers, R [National Aeronautics and Space Administration, Greenbelt, Md. (USA). Goddard Space Flight Center

    1976-08-05

    Reference is made to the apparent absence, or deficiency, of white dwarfs fainter than about 10/sup -4/L solar mass. An explanation is here proposed on the basis of Dirac's cosmological hypothesis that the gravitational constant, G, has varied with the time elapsed since the beginning of the expansion of the Universe as t/sup -1/ and the number of particles in the Universe has increases as t/sup 2/, if the measurements are made in atomic units. For a white dwarf the Chandrasekhar mass limit is a collection of fundamental constants proportional to Gsup(-3/2) and therefore increases with time as tsup(3/2). In the 'additive' version of Dirac's theory the actual mass, M, of a relatively small object like a star remains essentially unchanged by the creation of new matter in the Universe and hence a white dwarf will become more stable with the course of time; but in the 'multiplicative' version of the theory, M increases as t/sup 2/ and may eventually exceed the Chandrasekhar limit, and if this happens, gravitational collapse of the white dwarf into an invisible black hole or neutron star will quickly occur. It is considered interesting to find whether the 'multiplicative' theory may have a bearing on the apparent deficiency of faint white dwarfs, and to consider whether there are any possible consequences for galactic evolution. This is here discussed.

  1. Comparison of allergenicity and allergens between fish white and dark muscles.

    Science.gov (United States)

    Kobayashi, A; Tanaka, H; Hamada, Y; Ishizaki, S; Nagashima, Y; Shiomi, K

    2006-03-01

    Fish is one of the most frequent causes of immunoglobulin E (IgE)-mediated food allergy. Although the fish dark muscle is often ingested with the white muscle, no information about its allergenicity and allergens is available. Heated extracts were prepared from both white and dark muscles of five species of fish and examined for reactivity with IgE in fish-allergic patients by enzyme-linked immunosorbent assay (ELISA) and for allergens by immunoblotting. Cloning of cDNAs encoding parvalbumins was performed by rapid amplification cDNA ends. Parvalbumin contents in both white and dark muscles were determined by ELISA using antiserum against mackerel parvalbumin. Patient sera were less reactive to the heated extract from the dark muscle than to that from the white muscle. A prominent IgE-reactive protein of 12 kDa, which was detected in both white and dark muscles, was identified as parvalbumin. Molecular cloning experiments revealed that the same parvalbumin molecule is contained in both white and dark muscles of either horse mackerel or Pacific mackerel. Parvalbumin contents were four to eight times lower in the dark muscle than in the white muscle. The fish dark muscle is less allergenic than the white muscle, because the same allergen molecule (parvalbumin) is contained at much lower levels in the dark muscle than in the white muscle. Thus, the dark muscle is less implicated in fish allergy than the white muscle.

  2. Contribution to Kinetics of Formation of White Rust on Galvanized Steel

    International Nuclear Information System (INIS)

    Han, D. J.; Pyun, Su Il; Hahn, Y. D.

    1981-01-01

    Kinetics of formation of white rust on galvanized steel coated with various chromating solutions was studied. White rust occurs as a mixture of zinc oxide and zinc hydroxide. White rust formation rate was measured with a salt spray test as related to Cr 3+ ion amount, ratio of Cr 3+ to Cr 6+ ion(by weight) and surface roughness of the chromate film. Incubation time of white rust formation increased as the ratio of Cr 3+ to Cr 6+ ion in the chromate film increased. White rust propagation rate decreased as the amount of Cr 3+ ion increased. Surface roughness had no detectable relationship with incubation time and white rust propagation rate. Experimental results showed that kinetics of white rust formation was as follows: chromate film consists of insoluble Cr 3+ ion and soluble Cr 6+ ion, the latter act: as a corrosion inhibitor. Leaching rate of Cr 6+ ion from the film decreases with an increase of the ratio of Cr 3+ to Cr 6+ ion in the chromate film. When Cr 6+ ion is leached from the film, a bare zine layer is exposed to air and discontinuities occur in the film where white rust formation is initiated. Further white rust formation occurs due to destruction of the chromate film by chlorine ion. It is concluded that two stages of white rust formation are present and can be ascribed to Cr 6+ ion leaching and destruction of the chromate film by chlorine ion

  3. [Research on brain white matter network in cerebral palsy infant].

    Science.gov (United States)

    Li, Jun; Yang, Cheng; Wang, Yuanjun; Nie, Shengdong

    2017-10-01

    Present study used diffusion tensor image and tractography to construct brain white matter networks of 15 cerebral palsy infants and 30 healthy infants that matched for age and gender. After white matter network analysis, we found that both cerebral palsy and healthy infants had a small-world topology in white matter network, but cerebral palsy infants exhibited abnormal topological organization: increased shortest path length but decreased normalize clustering coefficient, global efficiency and local efficiency. Furthermore, we also found that white matter network hub regions were located in the left cuneus, precuneus, and left posterior cingulate gyrus. However, some abnormal nodes existed in the frontal, temporal, occipital and parietal lobes of cerebral palsy infants. These results indicated that the white matter networks for cerebral palsy infants were disrupted, which was consistent with previous studies about the abnormal brain white matter areas. This work could help us further study the pathogenesis of cerebral palsy infants.

  4. Origin of the DA and non-DA white dwarf stars

    Science.gov (United States)

    Shipman, Harry L.

    1989-01-01

    Various proposals for the bifurcation of the white dwarf cooling sequence are reviewed. 'Primordial' theories, in which the basic bifurcation of the white dwarf sequence is rooted in events predating the white dwarf stage of stellar evolution, are discussed, along with the competing 'mixing' theories in which processes occurring during the white dwarf stage are responsible for the existence of DA or non-DA stars. A new proposal is suggested, representing a two-channel scenario. In the DA channel, some process reduces the hydrogen layer mass to the value of less than 10 to the -7th. The non-DA channel is similar to that in the primordial scenario. These considerations suggest that some mechanism operates in both channels to reduce the thickness of the outermost layer of the white dwarf. It is also noted that accretion from the interstellar medium has little to do with whether a particular white dwarf becomes a DA or a non-DA star.

  5. Unpacking the invisible knapsack: The invention of white privilege pedagogy

    Directory of Open Access Journals (Sweden)

    Leslie Margolin

    2015-12-01

    Full Text Available This article uses Ricoeur’s hermeneutics of suspicion, an interpretive strategy directed to the hidden or repressed meanings behind texts, to examine the origins of white privilege pedagogy, in particular their foundational technique, “unpacking the invisible knapsack.” This article’s chief finding is that this pedagogy, though designed to fight racism, has the unintended effect of supporting white privilege. Teaching whites to “unpack their invisible knapsack” does not make them more willing to take action against racial inequality. On the contrary, it makes them more complacent, more at home in an unjust world, and more comfortable with their whiteness. White privilege pedagogy does this by focusing on personal identity (whites’ personal identity over institutional structures, by paying more attention to whites’ experiences than to blacks’, by falsely claiming that the confession of white privileges leads to social action beneficial to blacks, and by restoring and expanding whites’ sense of moral rightness.

  6. The High-Temperature Synthesis of the Nanoscaled White-Light Phosphors Applied in the White-Light LEDs

    Directory of Open Access Journals (Sweden)

    Hao-Ying Lu

    2015-01-01

    Full Text Available The white-light phosphors consisting of Dy3+ doped YPO4 and Dy3+ doped YP1-XVXO4 were prepared by the chemical coprecipitation method. After the 1200°C thermal treatment in the air atmosphere, the white-light phosphors with particle sizes around 90 nm can be obtained. In order to reduce the average particle size of phosphors, the alkaline washing method was applied to the original synthesis process, which reduces the particle sizes to 65 nm. From the PLE spectra, four absorption peaks locating at 325, 352, 366, and 390 nm can be observed in the YPO4-based phosphors. These peaks appear due to the following electron transitions: 6H15/2→4K15/2, 6H15/2→4M15/2+6P7/2, 6H15/2→4I11/2, and 6H15/2→4M19/2. Besides, the emission peaks of wavelengths 484 nm and 576 nm can be observed in the PL spectra. In order to obtain the white-light phosphors, the vanadium ions were applied to substitute the phosphorus ions to compose the YP1-XVXO4 phosphors. From the PL spectra, the strongest PL intensity can be obtained with 30% vanadium ions. As the concentration of vanadium ions increases to 40%, the phosphors with the CIE coordinates locating at the white-light area can be obtained.

  7. Racial residential segregation, socioeconomic disparities, and the White-Black survival gap.

    Directory of Open Access Journals (Sweden)

    Ioana Popescu

    Full Text Available To evaluate the association between racial residential segregation, a prominent manifestation of systemic racism, and the White-Black survival gap in a contemporary cohort of adults, and to assess the extent to which socioeconomic inequality explains this association.This was a cross sectional study of White and Black men and women aged 35-75 living in 102 large US Core Based Statistical Areas. The main outcome was the White-Black survival gap. We used 2009-2013 CDC mortality data for Black and White men and women to calculate age-, sex- and race adjusted White and Black mortality rates. We measured segregation using the Dissimilarity index, obtained from the Manhattan Institute. We used the 2009-2013 American Community Survey to define indicators of socioeconomic inequality. We estimated the CBSA-level White-Black gap in probability of survival using sequential linear regression models accounting for the CBSA dissimilarity index and race-specific socioeconomic indicators.Black men and women had a 14% and 9% lower probability of survival from age 35 to 75 than their white counterparts. Residential segregation was strongly associated with the survival gap, and this relationship was partly, but not fully, explained by socioeconomic inequality. At the lowest observed level of segregation, and with the Black socioeconomic status (SES assumed to be at the White SES level scenario, the survival gap is essentially eliminated.White-Black differences in survival remain wide notwithstanding public health efforts to improve life expectancy and initiatives to reduce health disparities. Eliminating racial residential segregation and bringing Black socioeconomic status (SES to White SES levels would eliminate the White-Black survival gap.

  8. NANOTECHNOLOGY WHITE PAPER | Science Inventory | US ...

    Science.gov (United States)

    Nanotechnology is the science of manipulating materials at the atomic and molecular level to develop new or enhanced materials and products. In December 2004, EPA’s Science Policy Council created a cross-Agency workgroup to identify and describe the issues EPA must address to ensure protection of human health and the environment as this new technology is developed. The draft white paper on nanotechnology is the product of the workgroup. The draft white paper describes the technology, and provides a discussion of the potential environmental benefits of nanotechnology and its applications that can foster sustainable use of resources. Risk management issues and the Agency’s statutory mandates are outlined, followed by an extensive discussion of risk assessment issues. The paper identifies research needs for both environmental applications and implications of nanotechnology and concludes with recommendations on next steps for addressing science policy issues and research needs. Supplemental information is provided in a number of appendices. The Agency will use the white paper to address research needs and risk assessment issues concerning nanotechnology. The draft white paper will undergo independent expert review, which will be conducted in the February time frame. All public comments received by January 31, 2006 will be submitted to the external review panel for their consideration. Comments received beyond that time will be considered by EPA. Follo

  9. The effects of in vitro exposure to white spirit on [Ca2+] in synaptosomes from rats exposed prenatally to white spirit

    DEFF Research Database (Denmark)

    Edelfors, S.; Hass, Ulla; Ravn-Jonsen, A.

    1999-01-01

    Female rats were exposed to white spirit (400 and 800 ppm for 6 hr/day) at day 7-20 during pregnancy. Thirty-five days after birth all female offspring were sacrificed, the brains removed, and the synaptosomal fractions prepared for in vitro studies. The cytosolic calcium concentration was measured...... using the FURA-2 technique. The results show that cytosolic calcium was increased in synaptosomes from rats exposed to white spirit prenatally compared to synaptosomes from unexposed rats. When synaptosomes were exposed to white spirit in vitro, the cytosolic calcium concentration changes were identical...... in all groups of rats. The membrane leakage measured as FURA-2 leakage from the synaptosomes identical in all three groups of animals. The results suggest that prenatal exposure to white spirit induces long-lasting and possibly irreversible changes in calcium homeostasis in the rat nervous system....

  10. Searching for white dwarfs candidates in Sloan Digital Sky Survey Data

    International Nuclear Information System (INIS)

    Nalezyty, Miroslaw; Majczyna, Agnieszka; Ciechanowska, Anna; Madej, Jerzy

    2009-01-01

    Large amount of observational spectroscopic data are recently available from different observational projects, like Sloan Digital Sky Survey. It's become more urgent to identify white dwarfs stars based on data itself i.e. without modelling white dwarf atmospheres. In particular, existing methods of white dwarfs identification presented in Kleinman et al. (2004) and in Eisenstein et al. (2006) did not allow to find all the white dwarfs in examined data. We intend to test various criteria of searching for white dwarf candidates, based on photometric and spectral features.

  11. A DEEPLY ECLIPSING DETACHED DOUBLE HELIUM WHITE DWARF BINARY

    International Nuclear Information System (INIS)

    Parsons, S. G.; Marsh, T. R.; Gaensicke, B. T.; Drake, A. J.; Koester, D.

    2011-01-01

    Using Liverpool Telescope+RISE photometry we identify the 2.78 hr period binary star CSS 41177 as a detached eclipsing double white dwarf binary with a 21,100 K primary star and a 10,500 K secondary star. This makes CSS 41177 only the second known eclipsing double white dwarf binary after NLTT 11748. The 2 minute long primary eclipse is 40% deep and the secondary eclipse 10% deep. From Gemini+GMOS spectroscopy, we measure the radial velocities of both components of the binary from the Hα absorption line cores. These measurements, combined with the light curve information, yield white dwarf masses of M 1 = 0.283 ± 0.064 M sun and M 2 = 0.274 ± 0.034 M sun , making them both helium core white dwarfs. As an eclipsing, double-lined spectroscopic binary, CSS 41177 is ideally suited to measuring precise, model-independent masses and radii. The two white dwarfs will merge in roughly 1.1 Gyr to form a single sdB star.

  12. White and Black American Children’s Implicit Intergroup Bias

    Science.gov (United States)

    Newheiser, Anna-Kaisa; Olson, Kristina R.

    2011-01-01

    Despite a decline in explicit prejudice, adults and children from majority groups (e.g., White Americans) often express bias implicitly, as assessed by the Implicit Association Test. In contrast, minority-group (e.g., Black American) adults on average show no bias on the IAT. In the present research, representing the first empirical investigation of whether Black children’s IAT responses parallel those of Black adults, we examined implicit bias in 7–11-year-old White and Black American children. Replicating previous findings with adults, whereas White children showed a robust ingroup bias, Black children showed no bias. Additionally, we investigated the role of valuing status in the development of implicit bias. For Black children, explicit preference for high status predicted implicit outgroup bias: Black children who explicitly expressed high preference for rich (vs. poor) people showed an implicit preference for Whites comparable in magnitude to White children’s ingroup bias. Implications for research on intergroup bias are discussed. PMID:22184478

  13. Racism in soccer? Perception of challenges of black and white players by white referees, soccer players, and fans.

    Science.gov (United States)

    Wagner-Egger, Pascal; Gygax, Pascal; Ribordy, Farfalla

    2012-02-01

    This experiment investigated challenge evaluations in soccer and their relation to prejudice: more precisely, whether skin colour may influence judgments of soccer tackles. Three groups of participants (soccer players, referees,and soccer fans) were asked to evaluate challenges, featuring Black and White players as aggressors and victims in a mixed-design study. Results showed that participants made some differentiations between Black and White players in a challenge evaluation task. Participants were more likely to consider within-group challenges as fouls and were faster to consider challenges made by Black players as fouls. On the other hand, fouls made by White players were seen as more severe. There were no major differences between the participating groups, suggesting that the observed effects were independent of how good players were or whether the participants were referees or not.

  14. White-Nose Syndrome Fungus (Geomyces destructans) in Bats, Europe

    OpenAIRE

    Wibbelt, Gudrun; Kurth, Andreas; Hellmann, David; Weishaar, Manfred; Barlow, Alex; Veith, Michael; Prüger, Julia; Görföl, Tamás; Grosche, Lena; Bontadina, Fabio; Zöphel, Ulrich; Seidl, Hans-Peter; Cryan, Paul M.; Blehert, David S.

    2010-01-01

    White-nose syndrome is an emerging disease in North America that has caused substantial declines in hibernating bats. A recently identified fungus (Geomyces destructans) causes skin lesions that are characteristic of this disease. Typical signs of this infection were not observed in bats in North America before white-nose syndrome was detected. However, unconfirmed reports from Europe indicated white fungal growth on hibernating bats without associated deaths. To investigate these differences...

  15. Environmental data for the White Oak Creek/White Oak Lake watershed: Environmental Sciences Division publication No. 2779

    International Nuclear Information System (INIS)

    Sherwood, C.B.; Loar, J.M.

    1987-01-01

    Oak Ridge National Laboratory (ORNL) is located in the White Oak Creek (WOC) watershed, which drains approximately 16.8 km 2 (6.5 mile 2 ). The waters of WOC are impounded by White Oak Dam at WOC's intersection with White Wing Road (State Route 95), 1.0 km (0.6 mile) upstream from the Clinch River. The resulting White Oak Lake (WOL) is a small, shallow impoundment, whose water level is controlled by a vertical sluice gate that remains in a fixed position during normal operations. White Oak Creek has been utilized for the discharge of treated and untreated wastes from routine operations since the Laboratory's inception. In addition, most of the more recent (1954 to date) liquid and solid low-level-waste disposal operations have been located in the drainage area of WOC. As a federally owned facility, ORNL is required to comply with all existing federal, state, and local environmental regulations regarding waste management. On July 15, 1985, the US Environmental Protection Agency published final rules to incorporate changes in the Resource Conservation and Recovery Act of 1976 that resulted from the passage of the Hazardous and Solid Waste Amendments of 1984. As a part of the rule changes, a new Sect. 3004(u) was added. The new section requires that any facility permit issued after November 8, 1984, include planned corrective actions for all continuing releases of hazardous waste or constituents from any disposal unit at the facility, regardless of when the waste was placed at the disposal unit. This report was prepared to compile existing information on the content and quantity of hazardous substances (both radioactive and nonradioactive) in the WOC/WOL watershed and to provide background information on the geology, hydrology, and ecology of the site for use in planning future remedial actions. 109 refs., 45 figs., 33 tabs

  16. Environmental data for the White Oak Creek/White Oak Lake watershed: Environmental Sciences Division publication No. 2779

    Energy Technology Data Exchange (ETDEWEB)

    Sherwood, C.B.; Loar, J.M.

    1987-01-01

    Oak Ridge National Laboratory (ORNL) is located in the White Oak Creek (WOC) watershed, which drains approximately 16.8 km/sup 2/ (6.5 mile/sup 2/). The waters of WOC are impounded by White Oak Dam at WOC's intersection with White Wing Road (State Route 95), 1.0 km (0.6 mile) upstream from the Clinch River. The resulting White Oak Lake (WOL) is a small, shallow impoundment, whose water level is controlled by a vertical sluice gate that remains in a fixed position during normal operations. White Oak Creek has been utilized for the discharge of treated and untreated wastes from routine operations since the Laboratory's inception. In addition, most of the more recent (1954 to date) liquid and solid low-level-waste disposal operations have been located in the drainage area of WOC. As a federally owned facility, ORNL is required to comply with all existing federal, state, and local environmental regulations regarding waste management. On July 15, 1985, the US Environmental Protection Agency published final rules to incorporate changes in the Resource Conservation and Recovery Act of 1976 that resulted from the passage of the Hazardous and Solid Waste Amendments of 1984. As a part of the rule changes, a new Sect. 3004(u) was added. The new section requires that any facility permit issued after November 8, 1984, include planned corrective actions for all continuing releases of hazardous waste or constituents from any disposal unit at the facility, regardless of when the waste was placed at the disposal unit. This report was prepared to compile existing information on the content and quantity of hazardous substances (both radioactive and nonradioactive) in the WOC/WOL watershed and to provide background information on the geology, hydrology, and ecology of the site for use in planning future remedial actions. 109 refs., 45 figs., 33 tabs.

  17. Some recent developments in white-pine weevil research in the Northeast

    Science.gov (United States)

    H. A. Jaynes

    1958-01-01

    Eastern white pine is one of the most important sawtimber species in the Northeast. This species would have still greater potential value were it not for the white-pine weevil, Pissodes strobi (Peck), its most serious insect pest. This is a native insect that occurs throughout the range of eastern white pine. A large percentage of the white pines in...

  18. An overview of white dwarf stars

    OpenAIRE

    Fontaine, Gilles; Brassard, Pierre; Charpinet, Stéphane; Randall, Suzanna K.; Van Grootel, Valérie

    2013-01-01

    We present a brief summary of what is currently known about white dwarf stars, with an emphasis on their evolutionary and internal properties. As is well known, white dwarfs represent the end products of stellar evolution for the vast majority of stars and, as such, bear the signatures of past events (such as mass loss, mixing phases, loss and redistribution of angular momentum, and thermonuclear burning) that are of essential importance in the evolution of stars in general. In addition, whit...

  19. Pulsations in white dwarfs: Selected topics

    Directory of Open Access Journals (Sweden)

    Saio H.

    2013-03-01

    Full Text Available This paper presents a very brief overview of the observed properties of g-mode pulsations in variable white dwarfs. We then discuss a few selected topics: Excitation mechanisms (kappa- and convection- mechanisms, and briefly the effect of a strong magnetic field (∼ 1 MG on g-modes as recently found in a hot DQ (carbon-rich atmosphere white dwarf. In the discussion of excitation mechanisms, a simple interpretation for the convection mechanism is given.

  20. White-centred retinal haemorrhages (Roth spots).

    Science.gov (United States)

    Ling, R; James, B

    1998-10-01

    Roth spots (white-centred retinal haemorrhages) were classically described as septic emboli lodged in the retina of patients with subacute bacterial endocarditis. Indeed many have considered Roth spots pathognomonic for this condition. More recent histological evidence suggests, however, that they are not foci of bacterial abscess. Instead, they are nonspecific and may be found in many other diseases. A review of the histology and the pathogenesis of these white-centred haemorrhages will be provided, along with the work-up of the differential diagnosis.

  1. Pulse radiolysis study of egg white

    International Nuclear Information System (INIS)

    Micic, O.I.; Josimovic, L.; Markovic, V.

    1978-01-01

    Radiolytic processes in egg white in intervals of 0.1μs to several seconds have been studied by the pulse radiolysis technique. The formation and decay of short-lived intermediates and their absorption spectra were observed under varied experimental conditions. The results show that intermediates are produced predominantly in reactions of radicals formed in water radiolysis with egg white proteins. The intermediates decay mainly in the first-order intermolecular processes, though the mechanism of transformations is very complex. (author)

  2. NGNP High Temperature Materials White Paper

    Energy Technology Data Exchange (ETDEWEB)

    Lew Lommers; George Honma

    2012-08-01

    This white paper is one in a series of white papers that address key generic issues of the combined construction and operating license (COL) pre-application program key generic issues for the Next Generation Nuclear Plant reactor using the prismatic block fuel technology. The purpose of the pre-application program interactions with the NRC staff is to reduce the time required for COL application review by identifying and addressing key regulatory issues and, if possible, obtaining agreements for their resolution

  3. Histopathology confirms white-nose syndrome in bats in Europe

    Science.gov (United States)

    Pikula, J.; Bandouchova, H.; Novotny, L.; Meteyer, C.U.; Zukal, J.; Irwin, N.R.; Zima, J.; Martinkova, N.

    2012-01-01

    White-nose syndrome, associated with the fungal skin infection geomycosis, caused regional population collapse in bats in North America. Our results, based on histopathology, show the presence of white-nose syndrome in Europe. Dermatohistopathology on two bats (Myotis myotis) found dead in March 2010 with geomycosis in the Czech Republic had characteristics resembling Geomyces destructans infection in bats confirmed with white-nose syndrome in US hibernacula. In addition, a live M. myotis, biopsied for histopathology during hibernation in April 2011, had typical fungal infection with cupping erosion and invasion of muzzle skin diagnostic for white-nose syndrome and conidiospores identical to G. destructans that were genetically confirmed as G. destructans. ?? Wildlife Disease Association 2012.

  4. Food habits of stunted and non-stunted white perch (Morone americana)

    Science.gov (United States)

    Gosch, N.J.C.; Stittie, J.R.; Pope, K.L.

    2010-01-01

    We studied food habits of white perch (Morone americana) from two populations with different stable states (stunted [Branched Oak Lake, Nebraska] and nonstunted [Pawnee Lake, Nebraska]) to determine if change in food habits of white perch is likely to occur in situations where a stunted white perch population is altered to a nonstunted state and vice versa. Three approaches were used to quantitatively describe seasonal (spring = March-May, summer = June-August, autumn = September-November) diets of white perch - 1) frequency of occurrence, 2) percentage of composition by volume, and 3) mean stomach fullness. White perch diets were dominated by cladocerans and dipterans in both reservoirs during all seasons. Fish egg predation was similar between reservoirs, and white perch rarely consumed fishes in either the stunted or the non-stunted population. Shifting a white perch population between stunted and non-stunted states will likely cause little or no change in food habits; fish in both states will primarily consume invertebrates.

  5. Short-range effects in large white dwarfs

    International Nuclear Information System (INIS)

    Membrado, M.C.; Pacheco, A.F.

    1988-01-01

    Recent work of Membrado and Pacheco (1988) on the implication of Yukawa-like effects in small white dwarfs is extended to analyze the very massive case. Although the role of these impurities grows substantially as the radius of the star decreases, when reasonable supergravity parameters are used the predicted change in the white dwarf mass-radius relation is unobservably small. 8 references

  6. Soliciting Performance, Hiding Bias: Whiteness and Librarianship

    Directory of Open Access Journals (Sweden)

    Angela Galvan

    2015-06-01

    Full Text Available Image by Flickr user tweng (CC BY-SA 2.0 In Brief: Despite the growing body of research on our professional demographics and multi-year diversity initiatives, librarianship in the United States remains overwhelmingly white. I suggest the interview process is a series of repetitive gestures designed to mimic and reinforce white middle class values, which ultimately influence […

  7. Worship Discourse and White Race-based Policy Attitudes

    Science.gov (United States)

    Brown, R. Khari; Kaiser, Angela; Jackson, James S.

    2014-01-01

    The current study relies upon the 2004 National Politics Study to examine the association between exposure to race-based messages within places of worship and White race-based policy attitudes. The present study challenges the notion that, for White Americans, religiosity inevitably leads to racial prejudice. Rather, we argue, as others have, that religion exists on a continuum that spans from reinforcing to challenging the status quo of social inequality. Our findings suggests that the extent to which Whites discuss race along with the potential need for public policy solutions to address racial inequality within worship spaces, worship attendance contributes to support for public policies aimed at reducing racial inequality. On the other hand, apolitical and non-structural racial discussions within worship settings do seemingly little to move many Whites to challenge dominant idealistic perceptions of race that eschews public policy interventions as solutions to racial inequality. PMID:25324579

  8. Possible new class of dense white dwarfs

    International Nuclear Information System (INIS)

    Glendenning, N.K.; Kettner, C.; Weber, F.

    1995-01-01

    If the strange quark matter hypothesis is true, then a new class of white dwarfs can exist whose nuclear material in their deep interiors can have a density as high as the neutron drip density, a few hundred times the density in maximum-mass white dwarfs and 4x10 4 the density in dwarfs of mass, M∼0.6 M circle-dot . Their masses fall in the approximate range 10 -4 to 1 M circle-dot . They are stable against acoustical modes of vibration. A strange quark core stabilizes these stars, which otherwise would have central densities that would place them in the unstable region of the sequence between white dwarfs and neutron stars. copyright 1995 American Institute of Physics

  9. White Dwarfs in Cataclysmic Variables: An Update

    Directory of Open Access Journals (Sweden)

    E. M. Sion

    2015-02-01

    Full Text Available In this review, we summarize what is currently known about the surface temperatures of accreting white dwarfs in nonmagnetic and magnetic cataclysmic variables (CVs based upon synthetic spectral analyses of far ultraviolet data. We focus only on white dwarf surface temperatures, since in the area of chemical abundances, rotation rates, WD masses and accretion rates, relatively little has changed since our last review, pending the results of a large HST GO programinvolving 48 CVs of different CV types. The surface temperature of the white dwarf in SS Cygni is re-examined in the light of its revised distance. We also discuss new HST spectra of the recurrent nova T Pyxidis as it transitioned into quiescence following its April 2011 nova outburst.

  10. Theoretical models for asteroseismology of DA white dwarf stars

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, P.A. [XTA, MS B220, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    1996-09-01

    Because white dwarfs are the most common end state of stellar evolution, determining their internal structure will yield many clues about the final stages of stellar evolution and the physics of matter under extreme conditions. We present the results of our parametric survey of evolutionary models of compositionally stratified white dwarfs with hydrogen surface layers (DA white dwarfs) and provide a comprehensive set of theoretical {ital g}-mode pulsation periods for comparison to observations of pulsating DA white dwarfs. This survey complements the previous survey of helium atmosphere (DB) white dwarf periods of Bradley, Winget, & Wood. We show how to use the periods of low-overtone and/or trapped modes to constrain the internal structure of pulsating DA white dwarfs by utilizing their sensitivity to the total stellar mass and the location of the hydrogen/helium transition zone. We use G117-B15A as an example to demonstrate the potential of our models for asteroseismology; we suggest that G117-B15A has a mass of 0.55 {ital M}{sub {circle_dot}} and a hydrogen layer mass of {approx_equal}1.5{times}10{sup {minus}4} {ital M}{sub {asterisk}}. {copyright} {ital 1996 The American Astronomical Society.}

  11. Education and black-white interracial marriage.

    Science.gov (United States)

    Gullickson, Aaron

    2006-11-01

    This article examines competing theoretical claims regarding how an individual's education will affect his or her likelihood of interracial marriage. I demonstrate that prior models of interracial marriage have failed to adequately distinguish the joint and marginal effects of education on interracial marriage and present a model capable of distinguishing these effects. I test this model on black-white interracial marriages using 1980, 1990, and 2000 U.S. census data. The results reveal partial support for status exchange theory within black male-white female unions and strong isolation of lower-class blacks from the interracial marriage market. Structural assimilation theory is not supported because the educational attainment of whites is not related in any consistent fashion to the likelihood of interracial marriage. The strong isolation of lower-class blacks from the interracial marriage market has gone unnoticed in prior research because of the failure of prior methods to distinguish joint and marginal effects.

  12. Histological study of white rhinoceros integument.

    Science.gov (United States)

    Plochocki, Jeffrey H; Ruiz, Saul; Rodriguez-Sosa, José R; Hall, Margaret I

    2017-01-01

    In this study, we report findings from a microscopic analysis of the white rhinoceros (Ceratotherium simum) integumentary ultrastructure. Skin samples from the cheek, shoulder, flank and rump were taken from a 46-year-old female southern white rhinoceros and examined using H&E and elastic histological stains. The epidermis was thickest in the flank (1.003 mm) followed by the rump, cheek and shoulder. The stratum corneum comprised more than half the epidermal thickness. Numerous melanin granules were found in the basal and spinosum layers. The epidermal-dermal junction was characterized by abundant papillary folds increasing surface contact between integument layers. Most of the dermal thickness consisted of organized collagen bundles with scattered elastic fibers. Collagen fiber bundles were thickest in the flank (210.9 μm) followed by shoulder, rump and cheek. Simple coiled sweat glands were present in the dermis, but hair and sebaceous glands were absent. Together, these data suggest the white rhinoceros has a unique integumentary system among large terrestrial herbivores.

  13. P3a from white noise.

    Science.gov (United States)

    Frank, David W; Yee, Ryan B; Polich, John

    2012-08-01

    P3a and P3b event-related brain potentials (ERPs) were elicited with an auditory three-stimulus (target, distracter, and standard) discrimination task in which subjects responded only to the target. Distracter stimuli consisted of white noise or novel sounds with stimulus characteristics perceptually matched. Target/standard discrimination difficulty was manipulated by varying target/standard pitch differences to produce relatively easy, medium, and hard tasks. Error rate and response time increased with increases in task difficulty. P3a was larger for the white noise compared to novel sounds, maximum over the central/parietal recording sites, and did not differ in size across difficulty levels. P3b was unaffected by distracter type, decreased as task difficulty increased, and maximum over the parietal recording sites. The findings indicate that P3a from white noise is robust and should be useful for applied studies as it removes stimulus novelty variability. Theoretical perspectives are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Ideology of white racial supremacy: colonization and de-colonization processes

    Directory of Open Access Journals (Sweden)

    Simone Gibran Nogueira

    2013-01-01

    Full Text Available This article is a literature review on how the ideology of white racial supremacy dehumanizes and colonizes the minds of Whites and Blacks in Brazil. For this aim I use critical references about whiteness to highlight dehumanization processes in Whites, and I make use of critical references of Black and African studies to examine specific dehumanization processes of the Black population. Furthermore, the work seeks to reflect on possibilities of mental humanization and de-colonization in both groups considering current policies of Affirmative Action in Education in Brazil.

  15. Recent advances on the formation and evolution of white dwarfs

    International Nuclear Information System (INIS)

    Sion, E.M.

    1986-01-01

    Advances made in the past seven years in both the theory and observation of white dwarfs which have led to major progress in understanding white dwarf formation and evolution are reviewed. The roles of convective dredge-up, mixing and dilution, accretion, gravitational and thermal diffusion in dense plasmas, radiate forces and mass outflow, nuclear shell burning, diffusion-induced reactions, late thermonuclear shell flashes, rotation, and magnetic fields in white dwarf evolution are considered. Recent work on the properties of white dwarfs in cataclysmic variables is briefly addressed. 153 references

  16. White Sands, New Mexico as seen from STS-60

    Science.gov (United States)

    1994-01-01

    White Sands National Monument (Park) is easily recognized in the center of this near-vertical color photograph. White Sands is the world's largest gypsum dune field. It represents an alabaster sea that covers nearly 300 square miles. At the southwest corner of the White Sands is dry lake, Lucero. In terms of cultural features the city of Alamogordo and Holloman Air Force Base can be seen with great clarity on this photograph.

  17. Management of white spots: resin infiltration technique and microabrasion

    Directory of Open Access Journals (Sweden)

    Jeong-Hye Son

    2011-01-01

    Full Text Available This case report compared the effectiveness of resin infiltration technique (Icon, DMG with microabrasion (Opalustre, Ultradent Products, Inc. in management of white spot lesions. It demonstrates that although neither microabrasion nor resin infiltration technique can remove white spot lesions completely, resin infiltration technique seems to be more effective than microabrasion. Therefore resin infiltration technique can be chosen preferentially for management of white spot lesions and caution should be taken for case selection.

  18. Contrast between white and grey matter: MRI appearance with ageing

    International Nuclear Information System (INIS)

    Magnaldi, S.; Ukmar, M.; Vasciaveo, A.; Longo, R.; Pozzi-Mucelli, R.S.

    1993-01-01

    MRI contrast between white and grey matter appears to be higher in young normal subjects than in older patients. The aim of the present study was to investigate the possible relationships between these changes in contrast and ageing. It consisted of two parts. In the first part we retrospectively evaluated 140 MRI brain examinations of healthy subjects, 20 per decade (age range 20-90 years), in whom the contrast was subjectively scored. In the second part we prospectively measured the actual T1, spin density (SD) and T2 values of white and grey matter in another 22 healthy subjects (age range 20-80 years). In the first group of subjects a progressive decrease in white/grey matter contrast was observed with ageing. In the second group of subjects the T1, SD and T2 values of white matter were always shorter than those of grey matter. There is a close relation among T1, SD and T2 values of white and grey matter with ageing. We suggest that there is a progressive loss of white/grey matter contrast with ageing. Such a phenomenon is possibly due to an increased water content in the white matter and the progressive neuronal loss in the grey matter that occurs with age. (orig.)

  19. Is white-coat hypertension a harbinger of increased risk?

    Science.gov (United States)

    Kollias, Anastasios; Ntineri, Angeliki; Stergiou, George S

    2014-09-01

    White-coat hypertension is defined by elevated office and normal out-of-office blood pressure (home or ambulatory) in untreated subjects. This condition is common in clinical practice and requires appropriate work-up for detection and management. Many studies have examined the relationship between white-coat hypertension and cardiovascular risk but with marked heterogeneity in the definitions and methodology applied. Thus, the results have been inconsistent leading to confusion in scientific research and clinical practice. Some but not all the relevant studies suggested that white-coat hypertension is associated with subclinical target-organ damage, yet the cross-sectional design of these studies and the fact that these indices are only surrogate end points do not allow firm conclusions to be drawn. In recent years, longitudinal studies have examined the prognostic significance of white-coat hypertension in terms of cardiovascular morbidity and mortality. Most of them indicate that white-coat hypertensive compared with normotensive subjects present a moderate-in most cases not significant-increase in risk. Meta-analyses of raw data from large databases, such as the International Database on Ambulatory blood pressure and Cardiovascular Outcomes (IDACO) and the International Database on HOme blood pressure in relation to Cardiovascular Outcomes (IDHOCO) allowed separate powered analyses in untreated subjects and provided a clearer picture regarding the modest risk associated with white-coat hypertension, especially in the long term. White-coat hypertension is regarded as an intermediate phenotype between normotension and hypertension associated with increased risk of developing sustained hypertension, and therefore requires regular follow-up using nonpharmacological measures.

  20. Site of delivery contribution to black-white severe maternal morbidity disparity.

    Science.gov (United States)

    Howell, Elizabeth A; Egorova, Natalia N; Balbierz, Amy; Zeitlin, Jennifer; Hebert, Paul L

    2016-08-01

    The black-white maternal mortality disparity is the largest disparity among all conventional population perinatal health measures, and the mortality gap between black and white women in New York City has nearly doubled in recent years. For every maternal death, 100 women experience severe maternal morbidity, a life-threatening diagnosis, or undergo a life-saving procedure during their delivery hospitalization. Like maternal mortality, severe maternal morbidity is more common among black than white women. A significant portion of maternal morbidity and mortality is preventable, making quality of care in hospitals a critical lever for improving outcomes. Hospital variation in risk-adjusted severe maternal morbidity rates exists. The extent to which variation in hospital performance on severe maternal morbidity rates contributes to black-white disparities in New York City hospitals has not been studied. We examined the extent to which black-white differences in severe maternal morbidity rates in New York City hospitals can be explained by differences in the hospitals in which black and white women deliver. We conducted a population-based study using linked 2011-2013 New York City discharge and birth certificate datasets (n = 353,773 deliveries) to examine black-white differences in severe maternal morbidity rates in New York City hospitals. A mixed-effects logistic regression with a random hospital-specific intercept was used to generate risk-standardized severe maternal morbidity rates for each hospital (n = 40). We then assessed differences in the distributions of black and white deliveries among these hospitals. Severe maternal morbidity occurred in 8882 deliveries (2.5%) and was higher among black than white women (4.2% vs 1.5%, P rates among New York City hospitals ranged from 0.8 to 5.7 per 100 deliveries. White deliveries were more likely to be delivered in low-morbidity hospitals: 65% of white vs 23% of black deliveries occurred in hospitals in the lowest

  1. White dwarf atmospheres and circumstellar environments

    CERN Document Server

    Hoard, Donald W

    2012-01-01

    Written by selected astronomers at the forefront of their fields, this timely and novel book compiles the latest results from research on white dwarf stars, complementing existing literature by focusing on fascinating new developments in our understanding of the atmospheric and circumstellar environments of these stellar remnants. Complete with a thorough refresher on the observational characteristics and physical basis for white dwarf classification, this is a must-have resource for researchers interested in the late stages of stellar evolution, circumstellar dust and nebulae, and the future

  2. Stroemgren photometry of southern white dwarfs

    International Nuclear Information System (INIS)

    Bessell, M.S.; Wickramasinghe, D.T.

    1978-01-01

    Colours of southern white dwarfs in the uvby (Stroemgren four-colour) system have been obtained. The results are compared with those of Graham. The extensive absolute photometry of white dwarfs published by Greenstein has also been transferred into the four-colour system and both sets of results are compared with model atmosphere calculations. The scatter in log (g) is higher than previously supposed, and the evidence for an increase in at the cooler (Tsub(e) < 10 000 K) end of the DA sequence is discussed. (author)

  3. Abnormal white matter properties in adolescent girls with anorexia nervosa

    Directory of Open Access Journals (Sweden)

    Katherine E. Travis

    2015-01-01

    Full Text Available Anorexia nervosa (AN is a serious eating disorder that typically emerges during adolescence and occurs most frequently in females. To date, very few studies have investigated the possible impact of AN on white matter tissue properties during adolescence, when white matter is still developing. The present study evaluated white matter tissue properties in adolescent girls with AN using diffusion MRI with tractography and T1 relaxometry to measure R1 (1/T1, an index of myelin content. Fifteen adolescent girls with AN (mean age = 16.6 years ± 1.4 were compared to fifteen age-matched girls with normal weight and eating behaviors (mean age = 17.1 years ± 1.3. We identified and segmented 9 bilateral cerebral tracts (18 and 8 callosal fiber tracts in each participant's brain (26 total. Tract profiles were generated by computing measures for fractional anisotropy (FA and R1 along the trajectory of each tract. Compared to controls, FA in the AN group was significantly decreased in 4 of 26 white matter tracts and significantly increased in 2 of 26 white matter tracts. R1 was significantly decreased in the AN group compared to controls in 11 of 26 white matter tracts. Reduced FA in combination with reduced R1 suggests that the observed white matter differences in AN are likely due to reductions in myelin content. For the majority of tracts, group differences in FA and R1 did not occur within the same tract. The present findings have important implications for understanding the neurobiological factors underlying white matter changes associated with AN and invite further investigations examining associations between white matter properties and specific physiological, cognitive, social, or emotional functions affected in AN.

  4. Pathological changes associated with white striping in broiler breast muscles.

    Science.gov (United States)

    Kuttappan, V A; Shivaprasad, H L; Shaw, D P; Valentine, B A; Hargis, B M; Clark, F D; McKee, S R; Owens, C M

    2013-02-01

    White striping is a condition in broiler chickens characterized grossly by the occurrence of white striations, seen parallel to the direction of muscle fibers, on broiler breast fillets and thighs. Based on visual evaluation of the intensity of white striping, breast fillets can be categorized into normal (NORM), moderate (MOD), and severe (SEV) categories. This study was undertaken to evaluate the details of changes in histology as well as proximate composition occurring in the fillets with respect to the 3 degrees of white striping. In experiment 1, representative breast fillets for each degree of white striping (n = 20) were collected from 45-d-old broilers, approximately 2 h postmortem. From each fillet, 2 skeletal muscle samples were obtained and fixed in 10% neutral buffered formalin. To identify and differentiate the histological changes, slides were prepared and stained using hematoxylin and eosin, Masson's Trichrome, and Oil Red O stains. In experiment 2, samples with 3 degrees of white striping were collected from 57-d-old birds for conducting proximate analysis. Major histopathological changes observed in the MOD and SEV samples consisted of loss of cross striations, variability in fiber size, floccular/vacuolar degeneration and lysis of fibers, mild mineralization, occasional regeneration (nuclear rowing and multinucleated cells), mononuclear cell infiltration, lipidosis, and interstitial inflammation and fibrosis. Microscopic lesions were visually scored for degeneration and necrosis, fibrosis, and lipidosis. The scale used to score the samples ranged from 0 (normal) to 3 (severe). There was an increase (P white striping increased from NORM to SEV. The results from the histopathological study were supported by the findings from proximate analysis confirming that the fat and protein contents of muscle increased (P white striping increased. In conclusion, the histopathological changes occurring in white striping indicate a degenerative myopathy that

  5. Abnormal white matter properties in adolescent girls with anorexia nervosa

    Science.gov (United States)

    Travis, Katherine E.; Golden, Neville H.; Feldman, Heidi M.; Solomon, Murray; Nguyen, Jenny; Mezer, Aviv; Yeatman, Jason D.; Dougherty, Robert F.

    2015-01-01

    Anorexia nervosa (AN) is a serious eating disorder that typically emerges during adolescence and occurs most frequently in females. To date, very few studies have investigated the possible impact of AN on white matter tissue properties during adolescence, when white matter is still developing. The present study evaluated white matter tissue properties in adolescent girls with AN using diffusion MRI with tractography and T1 relaxometry to measure R1 (1/T1), an index of myelin content. Fifteen adolescent girls with AN (mean age = 16.6 years ± 1.4) were compared to fifteen age-matched girls with normal weight and eating behaviors (mean age = 17.1 years ± 1.3). We identified and segmented 9 bilateral cerebral tracts (18) and 8 callosal fiber tracts in each participant's brain (26 total). Tract profiles were generated by computing measures for fractional anisotropy (FA) and R1 along the trajectory of each tract. Compared to controls, FA in the AN group was significantly decreased in 4 of 26 white matter tracts and significantly increased in 2 of 26 white matter tracts. R1 was significantly decreased in the AN group compared to controls in 11 of 26 white matter tracts. Reduced FA in combination with reduced R1 suggests that the observed white matter differences in AN are likely due to reductions in myelin content. For the majority of tracts, group differences in FA and R1 did not occur within the same tract. The present findings have important implications for understanding the neurobiological factors underlying white matter changes associated with AN and invite further investigations examining associations between white matter properties and specific physiological, cognitive, social, or emotional functions affected in AN. PMID:26740918

  6. "Compromises That We Make": Whiteness in the Dual Language Context

    Science.gov (United States)

    Burns, Meg

    2017-01-01

    This case study of a two-way dual language school explores the role of whiteness in a bilingual space, specifically with regards to parent involvement. I ask how whiteness operates in this setting and how the school's response to parent involvement reflects and/or challenges white supremacy. Using the concept of "interest convergence"…

  7. White-Coat Hypertension: When Blood Pressure Rises at the Doctor's Office

    Science.gov (United States)

    White coat hypertension: When blood pressure rises at the doctor's office My blood pressure is always higher in the ... You could have a condition known as white coat hypertension. White coat hypertension occurs when the blood ...

  8. Some engineering properties of white kidney beans (Phaseolus ...

    African Journals Online (AJOL)

    ajl yemi

    2011-12-19

    Dec 19, 2011 ... ... (physical and mechanical) properties, white kidney beans, moisture content, thousand grain mass, static coefficient of friction. INTRODUCTION. White kidney beans (Phaseolus vulgaris L.) are a culti- vated plant grown for fresh and dry consumption and a common raw material in the canned food industry.

  9. White OLED with a single-component europium complex.

    Science.gov (United States)

    Law, Ga-Lai; Wong, Ka-Leung; Tam, Hoi-Lam; Cheah, Kok-Wai; Wong, Wing-Tak

    2009-11-16

    A new direction for white organic light-emitting devices is shown, fabricated from a novel europium complex; this single component contains a double emission center of bluish-green and red, combined to a give a pure white emission (CIE x = 0.34 and y = 0.35).

  10. Management of post-orthodontic white spot lesions

    DEFF Research Database (Denmark)

    Sonesson, Mikael; Bergstrand, Fredrik; Gizani, Sotiria

    2016-01-01

    BACKGROUND/OBJECTIVES: The management of post-orthodontic white spot lesions is based on remineralization strategies or a minimal-invasive camouflage of the lesions. AIM: The aim of this systematic review was to identify and assess the quality of evidence for the various clinical technologies......-orthodontic white spot lesions. Further well-performed controlled clinical trials with long-term follow-up are needed to establish best clinical practice....

  11. Differential effects of white noise in cognitive and perceptual tasks

    Directory of Open Access Journals (Sweden)

    Nora Alicia Herweg

    2015-11-01

    Full Text Available Beneficial effects of noise on higher cognition have recently attracted attention. Hypothesizing an involvement of the mesolimbic dopamine system and its functional interactions with cortical areas, the current study aimed to demonstrate a facilitation of dopamine-dependent attentional and mnemonic functions by externally applying white noise in five behavioral experiments including a total sample of 167 healthy human subjects. During working memory, acoustic white noise impaired accuracy when presented during the maintenance period (experiment 1-3. In a reward based long-term memory task, white noise accelerated perceptual judgments for scene images during encoding but left subsequent recognition memory unaffected (experiment 4. In a modified Posner task (experiment 5, the benefit due to white noise in attentional orienting correlated weakly with reward dependence, a personality trait that has been associated with the dopaminergic system. These results suggest that white noise has no general effect on cognitive functions. Instead, they indicate differential effects on perception and cognition depending on a variety of factors such as task demands and timing of white noise presentation.

  12. Imaging camera system of OYGBR-phosphor-based white LED lighting

    Science.gov (United States)

    Kobashi, Katsuya; Taguchi, Tsunemasa

    2005-03-01

    The near-ultraviolet (nUV) white LED approach is analogous to three-color fluorescent lamp technology, which is based on the conversion of nUV radiation to visible light via the photoluminescence process in phosphor materials. The nUV light is not included in the white light generation from nUV-based white LED devices. This technology can thus provide a higher quality of white light than the blue and YAG method. A typical device demonstrates white luminescence with Tc=3,700 K, Ra > 93, K > 40 lm/W and chromaticity (x, y) = (0.39, 0.39), respectively. The orange, yellow, green and blue OYGB) or orange, yellow, red, green and blue (OYRGB) device shows a luminescence spectrum broader than of an RGB white LED and a better color rendering index. Such superior luminous characteristics could be useful for the application of several kinds of endoscope. We have shown the excellent pictures of digestive organs in a stomach of a dog due to the strong green component and high Ra.

  13. Differential effects of white noise in cognitive and perceptual tasks.

    Science.gov (United States)

    Herweg, Nora A; Bunzeck, Nico

    2015-01-01

    Beneficial effects of noise on higher cognition have recently attracted attention. Hypothesizing an involvement of the mesolimbic dopamine system and its functional interactions with cortical areas, the current study aimed to demonstrate a facilitation of dopamine-dependent attentional and mnemonic functions by externally applying white noise in five behavioral experiments including a total sample of 167 healthy human subjects. During working memory, acoustic white noise impaired accuracy when presented during the maintenance period (Experiments 1-3). In a reward based long-term memory task, white noise accelerated perceptual judgments for scene images during encoding but left subsequent recognition memory unaffected (Experiment 4). In a modified Posner task (Experiment 5), the benefit due to white noise in attentional orienting correlated weakly with reward dependence, a personality trait that has been associated with the dopaminergic system. These results suggest that white noise has no general effect on cognitive functions. Instead, they indicate differential effects on perception and cognition depending on a variety of factors such as task demands and timing of white noise presentation.

  14. MR imaging of metabolic white matter diseases: Therapeutic response

    International Nuclear Information System (INIS)

    Gebarski, S.S.; Allen, R.

    1987-01-01

    In metabolic diseases affecting the brain, MR imaging abnormalities include white-matter signal aberrations suggesting myelination delay, dysmyelination and demyelination, pathologic iron storage, and finally, loss of substance usually in a nonspecific pattern. The authors suggest that MR imaging may have therapeutic implications: (1) classic galactosemia - white-matter signal aberration became normal after dietary therapy; (2) phenylketonuria - age- and sex-matched treated and nontreated adolescents showed marked differences in brain volume, with the treated patient's volume nearly normal; (3) maple syrup urine disease - gross white-matter signal aberration became nearly normal after dietary therapy; and (4) hyperglycinemia - relentless progression of white-matter signal aberration and loss of brain substance despite therapy. These data suggest that brain MR imaging may provide a therapeutic index in certain metabolic diseases

  15. Chemical changes of proteins of irradiated egg-white

    International Nuclear Information System (INIS)

    Hajos, G.; Kiss, I.; Halasz, A.

    1990-01-01

    The effect of ionizing radiation (Co-60) was studied on egg-white proteins. Our earlier study revealed that the functional properties of egg-white depend on the dose of radiation and 3 kGy was found as optimal from the microbiological point of view. The effect of radiation on the protein structure was investigated in the dose range of 0-12 kGy using SDS polyacrylamide gel electrophoresis. The effect of this treatment was compared in fresh, frozen, and freeze-dried samples and in a 1% aqueous solution of egg-white. In aqueous solution a very important change was a marked formation of aggregates induced by radiation at doses of 1.5, 6.0 and 12.0 kGy. The effect of radiation was found to be much smaller in the freeze-dried and frozen samples. Electrophoretic investigations suggest the formation of radiation-induced aggregates, whereas effects in fresh egg-white were much smaller. (author)

  16. Absolute negative mobility induced by white Poissonian noise

    International Nuclear Information System (INIS)

    Spiechowicz, J; Łuczka, J; Hänggi, P

    2013-01-01

    We study the transport properties of inertial Brownian particles which move in a symmetric periodic potential and are subjected to both a symmetric, unbiased time-periodic external force and a biased Poissonian white shot noise (of non-zero average F) which is composed of a random sequence of δ-shaped pulses with random amplitudes. Upon varying the parameters of the white shot noise, one can conveniently manipulate the transport direction and the overall nonlinear response behavior. We find that within tailored parameter regimes the response is opposite to the applied average bias F of such white shot noise. This particular transport characteristic thus mimics that of a nonlinear absolute negative mobility (ANM) regime. Moreover, such white shot noise driven ANM is robust with respect to the statistics of the shot noise spikes. Our findings can be checked and corroborated experimentally by the use of a setup that consists of a single resistively and capacitively shunted Josephson junction device. (paper)

  17. The applications of VIP 397/418 bulbs in free radical white pigmented coatings: UV curing evaluation for different free radical white pigmented formulations (I)

    International Nuclear Information System (INIS)

    Rong Bao; McCartney, R.

    1999-01-01

    White pigmented coatings have gained commercial success using a Gallium doped microwave F600-V bulb. A novel VIP 397/418 bulb has been made recently, by Fusion UV Systems, to increase UV curing efficiency of white pigmented coatings. Previous research work has shown that the VIP 397/418 bulb can cure cationic white pigmented coatings 40-60% faster than a F600-V bulb. Further evaluations of free radical white pigmented coatings have produced significant data indicating that better physical properties (40-50%) or higher cure speeds (50%) can be obtained by using the VIP 397/418 bulb than a F600-V bulb

  18. Blister rust control in the management of western white pine

    Science.gov (United States)

    Kenneth P. Davis; Virgil D. Moss

    1940-01-01

    The forest industry of the western white pine region depends on the production of white pine as a major species on about 2,670,000 acres of commercial forest land. Continued production of this species and maintenance of the forest industry at anything approaching its present level is impossible unless the white pine blister rust is controlled. Existing merchantable...

  19. Cigarette smoking increases white blood cell aggregation in whole blood.

    OpenAIRE

    Bridges, A B; Hill, A; Belch, J J

    1993-01-01

    We studied the effect of chronic cigarette smoking on white blood cell aggregation, increased aggregation predisposes to microvascular occlusion and damage. Current smokers had significantly increased white blood cell aggregation when compared with non smokers. The presence of chronically activated white blood cells in current smokers may be relevant in the pathogenesis of ischaemic vascular disease.

  20. "Things Get Glossed Over": Rearticulating the Silencing Power of Whiteness in Education

    Science.gov (United States)

    Haviland, Victoria S.

    2008-01-01

    This article investigates the ways that White teachers approach issues of race, racism, and White supremacy in White-dominated educational settings. Drawing from data from a yearlong qualitative research study, the article uses discourse analysis, critical studies of Whiteness, and feminist theory to detail 15 rhetorical, behavioral, analytical,…

  1. White matter damage is related to ataxia severity in SCA3.

    Science.gov (United States)

    Kang, J-S; Klein, J C; Baudrexel, S; Deichmann, R; Nolte, D; Hilker, R

    2014-02-01

    Spinocerebellar ataxia type 3 (SCA3) is the most frequent inherited cerebellar ataxia in Europe, the US and Japan, leading to disability and death through motor complications. Although the affected protein ataxin-3 is found ubiquitously in the brain, grey matter atrophy is predominant in the cerebellum and the brainstem. White matter pathology is generally less severe and thought to occur in the brainstem, spinal cord, and cerebellar white matter. Here, we investigated both grey and white matter pathology in a group of 12 SCA3 patients and matched controls. We used voxel-based morphometry for analysis of tissue loss, and tract-based spatial statistics (TBSS) on diffusion magnetic resonance imaging to investigate microstructural pathology. We analysed correlations between microstructural properties of the brain and ataxia severity, as measured by the Scale for the Assessment and Rating of Ataxia (SARA) score. SCA3 patients exhibited significant loss of both grey and white matter in the cerebellar hemispheres, brainstem including pons and in lateral thalamus. On between-group analysis, TBSS detected widespread microstructural white matter pathology in the cerebellum, brainstem, and bilaterally in thalamus and the cerebral hemispheres. Furthermore, fractional anisotropy in a white matter network comprising frontal, thalamic, brainstem and left cerebellar white matter strongly and negatively correlated with SARA ataxia scores. Tractography identified the thalamic white matter thus implicated as belonging to ventrolateral thalamus. Disruption of white matter integrity in patients suffering from SCA3 is more widespread than previously thought. Moreover, our data provide evidence that microstructural white matter changes in SCA3 are strongly related to the clinical severity of ataxia symptoms.

  2. Racial residential segregation, socioeconomic disparities, and the White-Black survival gap

    Science.gov (United States)

    Duffy, Erin; Mendelsohn, Joshua; Escarce, José J.

    2018-01-01

    Objective To evaluate the association between racial residential segregation, a prominent manifestation of systemic racism, and the White-Black survival gap in a contemporary cohort of adults, and to assess the extent to which socioeconomic inequality explains this association. Design This was a cross sectional study of White and Black men and women aged 35–75 living in 102 large US Core Based Statistical Areas. The main outcome was the White-Black survival gap. We used 2009–2013 CDC mortality data for Black and White men and women to calculate age-, sex- and race adjusted White and Black mortality rates. We measured segregation using the Dissimilarity index, obtained from the Manhattan Institute. We used the 2009–2013 American Community Survey to define indicators of socioeconomic inequality. We estimated the CBSA-level White–Black gap in probability of survival using sequential linear regression models accounting for the CBSA dissimilarity index and race-specific socioeconomic indicators. Results Black men and women had a 14% and 9% lower probability of survival from age 35 to 75 than their white counterparts. Residential segregation was strongly associated with the survival gap, and this relationship was partly, but not fully, explained by socioeconomic inequality. At the lowest observed level of segregation, and with the Black socioeconomic status (SES) assumed to be at the White SES level scenario, the survival gap is essentially eliminated. Conclusion White-Black differences in survival remain wide notwithstanding public health efforts to improve life expectancy and initiatives to reduce health disparities. Eliminating racial residential segregation and bringing Black socioeconomic status (SES) to White SES levels would eliminate the White-Black survival gap. PMID:29474451

  3. Vertebral bomb radiocarbon suggests extreme longevity in white sharks.

    Science.gov (United States)

    Hamady, Li Ling; Natanson, Lisa J; Skomal, Gregory B; Thorrold, Simon R

    2014-01-01

    Conservation and management efforts for white sharks (Carcharodon carcharias) remain hampered by a lack of basic demographic information including age and growth rates. Sharks are typically aged by counting growth bands sequentially deposited in their vertebrae, but the assumption of annual deposition of these band pairs requires testing. We compared radiocarbon (Δ(14)C) values in vertebrae from four female and four male white sharks from the northwestern Atlantic Ocean (NWA) with reference chronologies documenting the marine uptake of (14)C produced by atmospheric testing of thermonuclear devices to generate the first radiocarbon age estimates for adult white sharks. Age estimates were up to 40 years old for the largest female (fork length [FL]: 526 cm) and 73 years old for the largest male (FL: 493 cm). Our results dramatically extend the maximum age and longevity of white sharks compared to earlier studies, hint at possible sexual dimorphism in growth rates, and raise concerns that white shark populations are considerably more sensitive to human-induced mortality than previously thought.

  4. Sea ice - Multiyear cycles and white ice

    Science.gov (United States)

    Ledley, T. S.

    1985-01-01

    The multiyear thickness cycles represent one of the interesting features of the sea ice studies performed by Semtner (1976) and Washington et al. (1976) with simple thermodynamic models of sea ice. In the present article, a description is given of results which show that the insulating effect of snow on the surface of the sea ice is important in producing these multiyear cycles given the physics included in the model. However, when the formation of white ice is included, the cycles almost disappear. White ice is the ice which forms at the snow-ice interface when the snow layer becomes thick enough to depress the ice below the water level. Water infiltrates the snow by coming through the ice at leads and generally freezes there, forming white ice.

  5. Suppression of cooling by strong magnetic fields in white dwarf stars.

    Science.gov (United States)

    Valyavin, G; Shulyak, D; Wade, G A; Antonyuk, K; Zharikov, S V; Galazutdinov, G A; Plachinda, S; Bagnulo, S; Machado, L Fox; Alvarez, M; Clark, D M; Lopez, J M; Hiriart, D; Han, Inwoo; Jeon, Young-Beom; Zurita, C; Mujica, R; Burlakova, T; Szeifert, T; Burenkov, A

    2014-11-06

    Isolated cool white dwarf stars more often have strong magnetic fields than young, hotter white dwarfs, which has been a puzzle because magnetic fields are expected to decay with time but a cool surface suggests that the star is old. In addition, some white dwarfs with strong fields vary in brightness as they rotate, which has been variously attributed to surface brightness inhomogeneities similar to sunspots, chemical inhomogeneities and other magneto-optical effects. Here we describe optical observations of the brightness and magnetic field of the cool white dwarf WD 1953-011 taken over about eight years, and the results of an analysis of its surface temperature and magnetic field distribution. We find that the magnetic field suppresses atmospheric convection, leading to dark spots in the most magnetized areas. We also find that strong fields are sufficient to suppress convection over the entire surface in cool magnetic white dwarfs, which inhibits their cooling evolution relative to weakly magnetic and non-magnetic white dwarfs, making them appear younger than they truly are. This explains the long-standing mystery of why magnetic fields are more common amongst cool white dwarfs, and implies that the currently accepted ages of strongly magnetic white dwarfs are systematically too young.

  6. Considerations for the optimization of induced white matter injury preclinical models

    Directory of Open Access Journals (Sweden)

    Abdullah Shafique Ahmad

    2015-08-01

    Full Text Available The white matter injury in relation to acute neurologic conditions, especially stroke, has remained obscure until recently. Current advances in the imaging technologies in the field of stroke have confirmed that white matter injury plays an important role in the prognosis of stroke and suggest that white matter protection is essential for functional recovery and post-stroke rehabilitation. However, due to the lack of a reproducible animal model of white matter injury, the pathophysiology and mechanisms of this injury are not well studied. Moreover, producing selective white matter injury in animals, especially in rodents, has proven to be challenging. Problems associated with inducing selective white matter ischemic injury in the rodent derive from differences in the architecture of the brain, most particularly the ratio of white matter to gray matter in rodents compared to humans, the agents used to induce the injury, and the location of the injury. Aging, gender differences, and comorbidities further add to this complexity. This review provides a brief account of the techniques commonly used to induce general white matter injury in animal models (stroke and non-stroke related and highlights relevance, optimization issues, and translational potentials associated with this particular form of injury.

  7. Towards a truer multicultural science education: how whiteness impacts science education

    Science.gov (United States)

    Le, Paul T.; Matias, Cheryl E.

    2018-03-01

    The hope for multicultural, culturally competent, and diverse perspectives in science education falls short if theoretical considerations of whiteness are not entertained. Since whiteness is characterized as a hegemonic racial dominance that has become so natural it is almost invisible, this paper identifies how whiteness operates in science education such that it falls short of its goal for cultural diversity. Because literature in science education has yet to fully entertain whiteness ideology, this paper offers one of the first theoretical postulations. Drawing from the fields of education, legal studies, and sociology, this paper employs critical whiteness studies as both a theoretical lens and an analytic tool to re-interpret how whiteness might impact science education. Doing so allows the field to reconsider benign, routine, or normative practices and protocol that may influence how future scientists of Color experience the field. In sum, we seek to have the field consider the theoretical frames of whiteness and how it might influence how we engage in science education such that our hope for diversity never fully materializes.

  8. Black-White Differences on the Vocational Preference Inventory

    Science.gov (United States)

    Doughtie, Eugene B.; And Others

    1976-01-01

    The Vocational Preference Inventory (VPI) was administered to black and white undergraduates. The overall VPI profiles of the two groups were significantly different. The black students scored higher on the Social, Conventional, Enterprising, Self-Control, Status, and Infrequency scales. The white students scored higher on the Masculinity scale.…

  9. Automated measurement of local white matter lesion volume

    DEFF Research Database (Denmark)

    van der Lijn, Fedde; Verhaaren, Benjamin F. J.; Ikram, M. Arfan

    2012-01-01

    in a periventricular region close to the ventricles and a subcortical zone further away. In this work we present a novel automated method for local white matter lesion volume quantification in magnetic resonance images. The method segments and measures the white matter lesion volume in 43 regions defined...

  10. 3D Morphology, Ultrastructure and Development of Ceratomyxa puntazzi Stages: First Insights into the Mechanisms of Motility and Budding in the Myxozoa

    Czech Academy of Sciences Publication Activity Database

    Alama-Bermejo, G.; Bron, J. E.; Raga, J. A.; Holzer, Astrid S.

    2012-01-01

    Roč. 7, č. 2 (2012), e32679 E-ISSN 1932-6203 Institutional support: RVO:60077344 Keywords : ELECTRON-MICROSCOPIC DESCRIPTION * BREAM SPARUS-AURATA * N-SP MYXOSPOREA * HOST-PARASITE RELATIONSHIP * DICENTRARCHUS-LABRAX L * CULTURED SEA BASS * TETRACAPSULOIDES-BRYOSALMONAE * DIPLODUS-PUNTAZZO * ENTERIC PARASITE * ACTIN DYNAMICS Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.730, year: 2012 http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0032679

  11. Estudio parasitológico de osteíctios de interés pesquero en Canarias

    OpenAIRE

    Cuyás Lazarich, Conchi

    2015-01-01

    Programa de doctorado: Medio Ambiente y Gestión de Recursos Marinos [ES]En el presente trabajo se ha estudiado la fauna parasitológica asociada a diez especies de peces de interés comercial para el Archipiélago Canario: Trachurus picturatus, Serranus atricauda, Diplodus sargus cadenati, Mullus surmuletus, Pagellus acarne, Pagellus erythrinus, Spondyliosoma cantharus, Scomber colias, Stephanolepis hispidus y Bothus podas maderensis. Se trata del primer trabajo en Canari...

  12. Permutation entropy of finite-length white-noise time series.

    Science.gov (United States)

    Little, Douglas J; Kane, Deb M

    2016-08-01

    Permutation entropy (PE) is commonly used to discriminate complex structure from white noise in a time series. While the PE of white noise is well understood in the long time-series limit, analysis in the general case is currently lacking. Here the expectation value and variance of white-noise PE are derived as functions of the number of ordinal pattern trials, N, and the embedding dimension, D. It is demonstrated that the probability distribution of the white-noise PE converges to a χ^{2} distribution with D!-1 degrees of freedom as N becomes large. It is further demonstrated that the PE variance for an arbitrary time series can be estimated as the variance of a related metric, the Kullback-Leibler entropy (KLE), allowing the qualitative N≫D! condition to be recast as a quantitative estimate of the N required to achieve a desired PE calculation precision. Application of this theory to statistical inference is demonstrated in the case of an experimentally obtained noise series, where the probability of obtaining the observed PE value was calculated assuming a white-noise time series. Standard statistical inference can be used to draw conclusions whether the white-noise null hypothesis can be accepted or rejected. This methodology can be applied to other null hypotheses, such as discriminating whether two time series are generated from different complex system states.

  13. Discriminatory Policy among the Undergraduate Students towards Racism and White Privilege in America

    Science.gov (United States)

    Sankar, G.

    2014-01-01

    This paper addresses racism and white privilege in America. Racism is generally discriminatory policy and behavior aimed at oppressing non whites whereas white privilege is the advantage gained by whites that is not due to ability or merit. It is argued that white privilege is largely invisible and that this allows the current unacceptable status…

  14. Ecological role of bluefin tuna (Thunnus thynnus) fish farms for associated wild fish assemblages in the Mediterranean Sea.

    Science.gov (United States)

    Stagličić, Nika; Šegvić-Bubić, Tanja; Ugarković, Pero; Talijančić, Igor; Žužul, Iva; Tičina, Vjekoslav; Grubišić, Leon

    2017-12-01

    The ecological effects of tuna fish farms are largely undocumented. This study confirmed their high capacity to attract surrounding wild fish. The aggregation effect persisted year round, without detectable seasonal differences. Farm impact was restricted to close proximity of the sea cages, and was more prominent over the bottom than in the water column strata. Tuna fish farms proved to be high energy trophic resources, as indicated by the enhanced fitness status of two focal species, bogue and seabream. Under abundant food supply, seabream appear to allocate the majority of energy reserves to gonad development. Farm associated bogue had greater parasite loads, with no detrimental effect on fitness status. Overall, tuna fish farms can be regarded as population sources for aggregated wild fish, and under the no fishing conditions within the leasehold areas, can serve as functional marine protected areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. White piedra and pediculosis capitis in the same patient.

    Science.gov (United States)

    Marques, Silvio Alencar; Richini-Pereira, Virgínia Bodelão; Camargo, Rosângela Maria Pires de

    2012-01-01

    White piedra is a superficial mycosis caused by the genus Trichosporon. It is characterized by nodules on the hair shaft. Pediculosis capitis is caused by Pediculus humanus var. capitis of the suborder Anoplura. Whereas pediculosis is a common infestation, clinical reports of white piedra are rare. Molecular biology procedures identified T. inkin as the agent of white piedra in this case report. The authors present associations between the two diseases in the same patient in order to highlight their clinical differences.

  16. Monaural ICA of white noise mixtures is hard

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Petersen, Kaare Brandt

    2003-01-01

    Separation of monaural linear mixtures of `white' source signals is fundamentally ill-posed. In some situations it is not possible to find the mixing coefficients for the full `blind' problem. If the mixing coefficients are known, the structure of the source prior distribution determines the sour...... of white noise signals and give a set of `no go' cases.......Separation of monaural linear mixtures of `white' source signals is fundamentally ill-posed. In some situations it is not possible to find the mixing coefficients for the full `blind' problem. If the mixing coefficients are known, the structure of the source prior distribution determines the source...

  17. White noise on bialgebras

    CERN Document Server

    Schürmann, Michael

    1993-01-01

    Stochastic processes with independent increments on a group are generalized to the concept of "white noise" on a Hopf algebra or bialgebra. The main purpose of the book is the characterization of these processes as solutions of quantum stochastic differential equations in the sense of R.L. Hudsonand K.R. Parthasarathy. The notes are a contribution to quantum probability but they are also related to classical probability, quantum groups, and operator algebras. The Az ma martingales appear as examples of white noise on a Hopf algebra which is a deformation of the Heisenberg group. The book will be of interest to probabilists and quantum probabilists. Specialists in algebraic structures who are curious about the role of their concepts in probablility theory as well as quantum theory may find the book interesting. The reader should havesome knowledge of functional analysis, operator algebras, and probability theory.

  18. Doing fandom, (misdoing whiteness: Heteronormativity, racialization, and the discursive construction of fandom

    Directory of Open Access Journals (Sweden)

    Mel Stanfill

    2011-11-01

    Full Text Available The fans depicted in mainstream media representation are unrelentingly white in a way that constructs fandom—from Star Trek to baseball to Elvis—as the property of white bodies. Though whiteness is typically understood in contemporary American culture as a position of privilege, represented fans seem to contradict this conventional wisdom; they are conceptualized in television shows, fictional films, and documentaries as white people deviating from the constructed-as-white norm of heterosexuality and employment through a "childish" fixation on the object of their fandom. Dominant culture produces an idea of fandom as a sort of failed nonheteronormative whiteness that serves a regulatory function, positioning the supposed inadequacy of fans as the result of bad—but correctable—decisions, reinforcing rather than challenging privilege as a natural property of white, heterosexual masculinity as it produces fandom as a racialized construct.

  19. Whiteness and Ethnocentric Monoculturalism: Making the "Invisible" Visible

    Science.gov (United States)

    Sue, Derald Wing

    2004-01-01

    Whiteness and ethnocentric monoculturalism are powerful and entrenched determinants of worldview. Because they are invisible and operate outside the level of conscious awareness, they can be detrimental to people of color, women, and other marginalized groups in society. Both define a reality that gives advantages to White Euro American males…

  20. Critical Conversations on Whiteness with Young Adult Literature

    Science.gov (United States)

    Schieble, Melissa

    2012-01-01

    In this article, the author argues that whiteness remains an overwhelmingly absent dimension in literacy teaching that addresses systems of power from a critical perspective. One way literacy teachers may bring this dimension more explicitly into the classroom is by facilitating critical conversations on whiteness with young adult literature. As…

  1. Dismantling the White Supremacy Embedded in Our Classrooms: White Faculty in Pursuit of More Equitable Educational Outcomes for Racially Minoritized Students

    Science.gov (United States)

    Haynes, Chayla

    2017-01-01

    An investigation of the literature revealed that racial consciousness and the behaviors of White faculty in the classroom appeared linked. A conceptual framework, Racial Consciousness and Its Influence on the Behaviors of White Faculty in the Classroom, was subsequently developed and tested in this constructivist grounded theory study. Findings…

  2. White noise enhances new-word learning in healthy adults.

    Science.gov (United States)

    Angwin, Anthony J; Wilson, Wayne J; Arnott, Wendy L; Signorini, Annabelle; Barry, Robert J; Copland, David A

    2017-10-12

    Research suggests that listening to white noise may improve some aspects of cognitive performance in individuals with lower attention. This study investigated the impact of white noise on new word learning in healthy young adults, and whether this effect was mediated by executive attention skills. Eighty participants completed a single training session to learn the names of twenty novel objects. The session comprised 5 learning phases, each followed by a recall test. A final recognition test was also administered. Half the participants listened to white noise during the learning phases, and half completed the learning in silence. The noise group demonstrated superior recall accuracy over time, which was not impacted by participant attentional capacity. Recognition accuracy was near ceiling for both groups. These findings suggest that white noise has the capacity to enhance lexical acquisition.

  3. Energy transport in radially accreting white dwarf stars

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, A.M.

    1986-10-01

    Some of the non-thermal energy transport processes which may be present in a white dwarf accretion column are examined and it is determined whether these could in any way contribute to a resolution of the soft X-ray puzzle. The first two Chapters of this Thesis constitute a review of the observations and proposed models for white dwarf accretion columns. In Chapter 3 we show that in Kuijpers and Pringle's original bombardment model of white dwarf accretion columns, in which the energy of the accreting material is deposited uniformly into a static atmosphere which then radiates the energy away as optically thin bremsstrahlung/line radiation, an incorrect Coulomb collisional timescale was used. In Chapter 4 we extend the calculations of Chapter 3 to include the effect of cyclotron radiation. It is concluded that a cyclotron cooled bombardment solution for a white dwarf accretion column may exist. We extend this calculation to derive a simple piecewise uniform temperature structure for such an accretion column, incorporating the effect of thermal conduction. In Chaper 5 we examine two of the non thermal emission mechanisms that might be present in white dwarf accretion columns:- non thermal Lyman-{alpha} emission and non thermal inverse bremsstrahlung emission. It is shown that neither would actually be sufficiently large to be detectable. In Chapter 6 some possible extensions to the work presented are suggested. (author).

  4. PROSPECT OF INDONESIA BLACK AND WHITE PEPPERS EXPORT

    Directory of Open Access Journals (Sweden)

    Tavi Supriana

    2013-04-01

    Full Text Available AbstractThis study analyzes the behavior of pepper exports, consisting of black pepper and white pepper, to various destination countries. The results of this study showed that black pepper exports affected by the destination country's gross domestic product (GDP, the price of white pepper, the population of the country of destination and the exchange rate against the dollar. Meanwhile, white pepper exports affected by the destination country's GDP, the population of the country of destination, the price of black pepper, white pepper prices and the exchange rate against the dollar. The results also showed that black pepper and white pepper are not mutually substituted.Keywords: pepper, exports, GDP, population, exchange rate JEL Classificaiton Numbers: F14, F19AbstrakPenelitian ini menganalisis perilaku ekspor lada, terdiri dari lada hitam dan lada putih, ke berbagai negara tujuan. Hasil penelitian ini menunjukkan bahwa ekspor lada hitam dipengaruhi oleh Pendapatan domestik bruto (PDB negara tujuan, harga lada putih, populasi negara tujuan dan nilai tukar rupiah terhadap dolar. Sementara itu, ekspor lada putih dipengaruhi oleh PDB negara tujuan, populasi negara tujuan, harga lada hitam, harga lada putih dan nilai tukar rupiah terhadap dolar. Hasil penelitian juga menunjukkan bahwa lada hitam dan lada putih tidak saling bersubstitusi.Keywords: Lada, ekspor, PDB, populasi, kursJEL Classificaiton Numbers: F14, F19

  5. Increased Executive Functioning, Attention, and Cortical Thickness in White-Collar Criminals

    Science.gov (United States)

    Raine, Adrian; Laufer, William S.; Yang, Yaling; Narr, Katherine L.; Thompson, Paul; Toga, Arthur W.

    2011-01-01

    Very little is known on white collar crime and how it differs to other forms of offending. This study tests the hypothesis that white collar criminals have better executive functioning, enhanced information processing, and structural brain superiorities compared to offender controls. Using a case-control design, executive functioning, orienting, and cortical thickness was assessed in 21 white collar criminals matched with 21 controls on age, gender, ethnicity, and general level of criminal offending. White collar criminals had significantly better executive functioning, increased electrodermal orienting, increased arousal, and increased cortical gray matter thickness in the ventromedial prefrontal cortex, inferior frontal gyrus, somatosensory cortex, and the temporal-parietal junction compared to controls. Results, while initial, constitute the first findings on neurobiological characteristics of white-collar criminals It is hypothesized that white collar criminals have information-processing and brain superiorities that give them an advantage in perpetrating criminal offenses in occupational settings. PMID:22002326

  6. Feeling threatened about the future: Whites' emotional reactions to anticipated ethnic demographic changes.

    Science.gov (United States)

    Outten, H Robert; Schmitt, Michael T; Miller, Daniel A; Garcia, Amber L

    2012-01-01

    In many Western countries, the proportion of the population that is White will drop below 50% within the next century. Two experiments examined how anticipation of these future ethnic demographics affects current intergroup processes. In Study 1, White Americans who viewed actual demographic projections for a time when Whites are no longer a numerical majority felt more angry toward and fearful of ethnic minorities than Whites who did not view future projections. Whites who viewed the future projections also felt more sympathy for their ingroup than Whites in the control condition. In Study 2, the authors replicated the effects for intergroup emotions with a sample of White Canadians. White Canadians who thought about a future in which Whites were a numerical minority appraised the ingroup as more threatened, which mediated the effect of condition on intergroup emotions. The authors discuss the implications of these findings for race relations in increasingly diverse societies.

  7. BIOMODIFICATION OF KENAF USING WHITE ROT FUNGI

    Directory of Open Access Journals (Sweden)

    Rasmina Halis,

    2012-01-01

    Full Text Available White rot fungi can be used as a pretreatment of biomass to degrade lignin. It also alters the structure of the lignocellulosic matter, thus increasing its accessibility to enzymes able to convert polysaccharides into simple sugars. This study compares the ability of two species of white rot fungi, Pycnoporous sanguineus and Oxyporus latemarginatus FRIM 31, to degrade lignin in kenaf chips. The white rot fungi were originally isolated from the tropical forest in Malaysia. Kenaf chips were first inoculated with each fungus separately using corn steep liquor as a fungal growth promoter. The kenaf chips were inoculated with white rot fungus for a period of 1, 2, 4, 8 and 16 weeks, after which they were observed under the scanning electron microscope (SEM. Chemical analyses were conducted following TAPPI Standard Methods and Fourier Transmission Infra Red (FTIR. SEM observations showed evidence of fungal colonization. When calculating weight loss, both P. sanguineus and O. latemarginatus FRIM 31 showed the greatest reduction. Amounts by mass of cellulose, hemicelluloses, extractives, and lignin in the treated kenaf chips all were lowered. The results show that O. latemarginatus FRIM 31 had a greater ability to degrade lignin when compared to P. sanguineus.

  8. Flora White (1860-1948): New Woman, Stark Choice

    Science.gov (United States)

    Morice, Linda C.

    2009-01-01

    This article examines the life of education reformer Flora White, who both represented and deviated from the stereotypical new woman portrayed in popular literature of the late nineteenth and early twentieth century. White's decision to reject marriage and children in favor of a career resulted in greater financial insecurity and an unmet desire…

  9. In vitro effects of virgin microplastics on fish head-kidney leucocyte activities.

    Science.gov (United States)

    Espinosa, Cristóbal; García Beltrán, José María; Esteban, María Angeles; Cuesta, Alberto

    2018-04-01

    Microplastics are well-documented pollutants in the marine environment that result from production or fragmentation of larger plastic items. The knowledge about the direct effects of microplastics on immunity, including fish, is still very limited. We investigated the in vitro effects of microplastics [polyvinylchloride (PVC) and polyethylene (PE)] on gilthead seabream (Sparus aurata) and European sea bass (Dicentrarchus labrax) head-kidney leucocytes (HKLs). After 1 and 24 h of exposure of HKLs with 0 (control), 1, 10 and 100 mg mL -1 MPs in a rotatory system, cell viability, innate immune parameters (phagocytic, respiratory burst and peroxidase activities) and the expression of genes related to inflammation (il1b), oxidative stress (nrf2, prdx3), metabolism of xenobiotics (cyp1a1, mta) and cell apoptosis (casp3) were studied. Microplastics failed to affect the cell viability of HKLs. In addition, they provoke very few significant effects on the main cellular innate immune activities, as decrease on phagocytosis or increase in the respiratory burst of HKLs with the highest dose of microplastics tested. Furthermore, microplastics failed to affect the expression of the selected genes on sea bass or seabream, except the nrf2 which was up-regulated in seabream HKLs incubated with the highest doses. Present results seem to suggest that continue exposure of fish to PVC or PE microplastics could impair fish immune parameters probably due to the oxidative stress produced in the fish leucocytes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Limonene: attractant kairomone for white pine cone beetles (Coleoptera: Scolytidae) in an Eastern white pine seed orchard in Western North Carolina

    Science.gov (United States)

    Daniel R. Miller

    2007-01-01

    I report on the attraction of the white pine cone beetle, Canophthorus coniperda (Schwarz) (Coleoptera: Scolytidae), to traps baited with the host monoterpene limonene in western North Carolina. Both (+)- and (-)-limonene attracted male and female cone beetles to Japenese beetle traps in an eastern white pine, Pinus strobus L. seed...

  11. Should policy ethics come in two colours: green or white?

    Science.gov (United States)

    Oswald, Malcolm

    2013-05-01

    When writing about policy, do you think in green or white? If not, I recommend that you do. I suggest that writers and journal editors should explicitly label every policy ethics paper either 'green' or 'white'. A green paper is an unconstrained exploration of a policy question. The controversial 'After-birth abortion' paper is an example. Had it been labelled as 'green', readers could have understood what Giubilini and Minerva explained later: that it was a discussion of philosophical ideas, and not a policy proposal advocating infanticide. A serious policy proposal should be labelled by writer(s) and editor(s) as 'white'. Its purpose should be to influence policy. In order to influence policy, I suggest three essential, and two desirable, characteristics of any white paper. Most importantly, a white paper should be set in the context in which the policy is to be made and applied.

  12. 75 FR 65415 - White House Initiative on Educational Excellence for Hispanics

    Science.gov (United States)

    2010-10-22

    ... Part II The President Executive Order 13555--White House Initiative on Educational Excellence for... Order 13555 of October 19, 2010 White House Initiative on Educational Excellence for Hispanics By the... will be substantially enhanced by improving educational outcomes for Hispanics. Sec. 2. White House...

  13. THE INITIAL-FINAL MASS RELATION AMONG WHITE DWARFS IN WIDE BINARIES

    International Nuclear Information System (INIS)

    Zhao, J. K.; Oswalt, T. D.; Willson, L. A.; Wang, Q.; Zhao, G.

    2012-01-01

    We present the initial-final mass relation derived from 10 white dwarfs in wide binaries that consist of a main-sequence star and a white dwarf. The temperature and gravity of each white dwarf were measured by fitting theoretical model atmospheres to the observed spectrum using a χ 2 fitting algorithm. The cooling time and mass were obtained using theoretical cooling tracks. The total age of each binary was estimated from the chromospheric activity of its main-sequence component to an uncertainty of about 0.17 dex in log t. The difference between the total age and white dwarf cooling time is taken as the main-sequence lifetime of each white dwarf. The initial mass of each white dwarf was then determined using stellar evolution tracks with a corresponding metallicity derived from spectra of their main-sequence companions, thus yielding the initial-final mass relation. Most of the initial masses of the white dwarf components are between 1 and 2 M ☉ . Our results suggest a correlation between the metallicity of a white dwarf's progenitor and the amount of post-main-sequence mass loss it experiences—at least among progenitors with masses in the range of 1-2 M ☉ . A comparison of our observations to theoretical models suggests that low-mass stars preferentially lose mass on the red giant branch.

  14. Double Degenerates among DA white dwarfs

    International Nuclear Information System (INIS)

    Bragaglia, A.; Greggio, L.; Renzini, A.; D'odorico, S.

    1990-01-01

    The results of a spectroscopic survey of catalog white dwarfs in search of radial velocity variations indicative of a binary motion are reported. In a sample of 54 DA white dwarfs, one Double Degenerate (DD) system with a period of 1.15 days (the shortest period DD system yet discovered) is found. Two other excellent and two good DD candidates, and two white dwarf + red dwarf pairs were also found. If all the candidates should be confirmed, this would indicate a frequency of about 13 percent of interacting binaries in an unbiased sample of evolved stars, with a DD frequency of about 10 percent. These results suggest fairly large values for the common-envelope parameter alpha, implying that a source of energy other than orbital may be required to eject the envelope during common-envelope events. Finally, in combination with previous evidence our result implies that DDs with WD components of the DA variety are unlikely to be the precursors of Type I supernovae, but DDs with non-DA components remain very attractive candidates. 20 refs

  15. Histological study of white rhinoceros integument.

    Directory of Open Access Journals (Sweden)

    Jeffrey H Plochocki

    Full Text Available In this study, we report findings from a microscopic analysis of the white rhinoceros (Ceratotherium simum integumentary ultrastructure. Skin samples from the cheek, shoulder, flank and rump were taken from a 46-year-old female southern white rhinoceros and examined using H&E and elastic histological stains. The epidermis was thickest in the flank (1.003 mm followed by the rump, cheek and shoulder. The stratum corneum comprised more than half the epidermal thickness. Numerous melanin granules were found in the basal and spinosum layers. The epidermal-dermal junction was characterized by abundant papillary folds increasing surface contact between integument layers. Most of the dermal thickness consisted of organized collagen bundles with scattered elastic fibers. Collagen fiber bundles were thickest in the flank (210.9 μm followed by shoulder, rump and cheek. Simple coiled sweat glands were present in the dermis, but hair and sebaceous glands were absent. Together, these data suggest the white rhinoceros has a unique integumentary system among large terrestrial herbivores.

  16. Black-on-white polymer-stabilized cholesteric formulations

    Science.gov (United States)

    West, John L.; Magyar, Gregory R.; Francl, James J.; Nixon, Christine M.

    1995-08-01

    Recent research by Doane, Yang, and Chien demonstrated the use of cholesteric liquid crystals in multiplexed, high resolution, reflective diplays. These materials utilize the bistability of the cholesteric planar and focal conic states for displays with a colored image on a black background. Many commercial applications of these materials, such as electronic books and newspapers, portable faxes and personal data assistants, require, or at least prefer, black-on- white images. We report on relatively high polymer content (equalsV 20% by weight) dispersions of cholesteric liquid crystals that produce a white, reflecting, planar state. The polymer network appears to form cholesteric domains with varying pitch lengths resulting in planar states that reflect in the red, green, and blue portions of the spectrum. Utilizing a black absorbing layer behind a display using these materials offers white images on a black background, or vice-versa.

  17. Diet composition and breeding cycle of blacktail, Diplodus sargus ...

    African Journals Online (AJOL)

    Ulva sp., Perna perna and Balanu,spp. were prefered species. A new index for ranking prey items, which combines the modified points method and the frequency of occurrence method, is suggested. It is especially useful for omnivorous fish where prey items sucl as seaweed and colonial organisms are difficult to ...

  18. Color Degradation of Textiles with Natural Dyes and of Blue Scale Standards Exposed to White LED Lamps:Evaluation of White LED Lamps for Effectiveness as Museum Lighting

    Science.gov (United States)

    Ishii, Mie; Moriyama, Takayoshi; Toda, Masahiro; Kohmoto, Kohtaro; Saito, Masako

    White light-emitting diodes (LED) are well suited for museum lighting because they emit neither UV nor IR radiation, which damage artifacts. The color degradation of natural dyes and blue scale standards (JIS L 0841) by white LED lamps are examined, and the performance of white LED lamps for museum lighting is evaluated. Blue scale standard grades 1-6 and silk fabrics dyed with 22 types of natural dyes classified as mid to highly responsive in a CIE technical report (CIE157:2004) were exposed to five types of white LED lamps using different luminescence methods and color temperatures. Color changes were measured at each 15000 lx·hr (500 lx at fabric surface × 300 hr) interval ten times. The accumulated exposure totaled 150000 lx·hr. The data on conventional white LED lamps and previously reported white fluorescent (W) and museum fluorescent (NU) lamps was evaluated. All the white LED lamps showed lower fading rates compared with a W lamp on a blue scale grade 1. The fading rate of natural dyes in total was the same between an NU lamp (3000 K) and a white LED lamp (2869 K). However, yellow natural dyes showed higher fading rates with the white LED lamp. This tendency is due to the high power characteristic of the LED lamp around 400-500 nm, which possibly contributes to the photo-fading action on the dyes. The most faded yellow dyes were Ukon (Curcuma longa L.) and Kihada (Phellodendron amurense Rupr.), and these are frequently used in historic artifacts such as kimono, wood-block prints, and scrolls. From a conservation point of view, we need to continue research on white LED lamps for use in museum lighting.

  19. White dwarfs: connection with masses of the parent stars

    International Nuclear Information System (INIS)

    Amnuel', P.R.; Guseinov, O.Kh.; Novruzova, Kh.I.; Rustamov, Yu.S.

    1988-01-01

    A relationship between the mass of a white dwarf and the mass of the parent star on the main sequence is established. The white dwarf birth-rate matches the birth-rate (death-rate) of main sequence stars

  20. ENERGY DISSIPATION THROUGH QUASI-STATIC TIDES IN WHITE DWARF BINARIES

    International Nuclear Information System (INIS)

    Willems, B.; Deloye, C. J.; Kalogera, V.

    2010-01-01

    We present a formalism to study tidal interactions in white dwarf binaries in the limiting case of quasi-static tides, in which the tidal forcing frequencies are small, compared to the inverse of the white dwarf's dynamical timescale. The formalism is valid for arbitrary orbital eccentricities and therefore applicable to white dwarf binaries in the Galactic disk as well as globular clusters. In the quasi-static limit, the total perturbation of the gravitational potential shows a phase shift with respect to the position of the companion, the magnitude of which is determined primarily by the efficiency of energy dissipation through convective damping. We determine rates of secular evolution of the orbital elements and white dwarf rotational angular velocity for a 0.3 M sun helium white dwarf in binaries with orbital frequencies in the Laser Interferometer Space Antenna (LISA) gravitational wave frequency band and companion masses ranging from 0.3 M sun to 10 5 M sun . The resulting tidal evolution timescales for the orbital semimajor axis are longer than a Hubble time, so that convective damping of quasi-static tides need not be considered in the construction of gravitational wave templates of white dwarf binaries in the LISA band. Spin-up of the white dwarf, on the other hand, can occur on timescales of less than 10 Myr, provided that the white dwarf is initially rotating with a frequency much smaller than the orbital frequency. For semi-detached white dwarf binaries spin-up can occur on timescales of less than 1 Myr. Nevertheless, the timescales remain longer than the orbital inspiral timescales due to gravitational radiation, so that the degree of asynchronism in these binaries increases. As a consequence, tidal forcing eventually occurs at forcing frequencies beyond the quasi-static tide approximation. For the shortest period binaries, energy dissipation is therefore expected to take place through dynamic tides and resonantly excited g-modes.

  1. White Namibians in tourism and the politics of belonging through Bushmen

    NARCIS (Netherlands)

    Koot, S.P.

    2015-01-01

    Namibian Bushmen, such as the Hai//om and the Ju/’hoansi, are increasingly involved in the growing, white-dominated tourism industry. In this, white Namibians tend to position Bushmen and themselves as people of nature and conservationists. Elsewhere, whites from southern Africa have avoided contact

  2. The Feynman integrand as a white noise distribution beyond perturbation theory

    International Nuclear Information System (INIS)

    Grothaus, Martin; Vogel, Anna

    2008-01-01

    In this note the concepts of path integrals and techniques how to construct them are presented. Here we concentrate on a White Noise approach. Combining White Noise techniques with a generalized time-dependent Doss' formula Feynman integrands are constructed as white noise distributions beyond perturbation theory

  3. Whites See Racism as a Zero-Sum Game That They Are Now Losing.

    Science.gov (United States)

    Norton, Michael I; Sommers, Samuel R

    2011-05-01

    Although some have heralded recent political and cultural developments as signaling the arrival of a postracial era in America, several legal and social controversies regarding "reverse racism" highlight Whites' increasing concern about anti-White bias. We show that this emerging belief reflects Whites' view of racism as a zero-sum game, such that decreases in perceived bias against Blacks over the past six decades are associated with increases in perceived bias against Whites-a relationship not observed in Blacks' perceptions. Moreover, these changes in Whites' conceptions of racism are extreme enough that Whites have now come to view anti-White bias as a bigger societal problem than anti-Black bias. © The Author(s) 2011.

  4. Histopathology of crustose coralline algae affected by white band and white patch diseases

    Directory of Open Access Journals (Sweden)

    Gaëlle Quéré

    2015-06-01

    Full Text Available Crustose coralline algae (CCA are major benthic calcifiers that play crucial roles in marine ecosystems, particularly coral reefs. Over the past two decades, epizootics have been reported for several CCA species on coral reefs worldwide. However, their causes remain often unknown in part because few studies have investigated CCA pathologies at a microscopic scale. We studied the cellular changes associated with two syndromes: Coralline White Band Syndrome (CWBS and Coralline White Patch Disease (CWPD from samples collected in Curaçao, southern Caribbean. Healthy-looking tissue of diseased CCA did not differ from healthy tissue of healthy CCA. In diseased tissues of both pathologies, the three characteristic cell layers of CCA revealed cells completely depleted of protoplasmic content, but presenting an intact cell wall. In addition, CWBS showed a transition area between healthy and diseased tissues consisting of cells partially deprived of protoplasmic material, most likely corresponding to the white band characterizing the disease at the macroscopic level. This transition area was absent in CWPD. Regrowth at the lesion boundary were sometimes observed in both syndromes. Tissues of both healthy and diseased CCA were colonised by diverse boring organisms. Fungal infections associated with the diseased cells were not seen. However, other bioeroders were more abundant in diseased vs healthy CCA and in diseased vs healthy-looking tissues of diseased CCA. Although their role in the pathogenesis is unclear, this suggests that disease increases CCA susceptibility to bioerosion. Further investigations using an integrated approach are needed to carry out the complete diagnosis of these diseases.

  5. White dwarf radii and boundary-layer constraints in three dwarf novae

    International Nuclear Information System (INIS)

    Wood, J.H.

    1990-01-01

    The structure of the boundary layer between the accretion disc and white dwarf in three quiescent dwarf novae is explored with high signal-to-noise eclipse light curves obtained by phase folding 12-20 eclipses. Models of the eclipse shapes of various white dwarf/boundary layer configurations that might be at the centres of the accretion discs are calculated and compared with observations of the eclipses in Z Cha, OY Car and HT Cas. Possible models for the central objects are found to be a white dwarf with or without its lower hemisphere occulted by the disc, or a white dwarf with an optically thick boundary layer significantly extended in latitude up and down its sides. The most likely of these models for each system is an unocculted white dwarf with no boundary layer contributing significantly to the optical flux, or a white dwarf totally covered by an optically thick boundary layer. (author)

  6. Ageing in old degenerates: asteroseismology of white dwarf stars

    International Nuclear Information System (INIS)

    O'Donoghue, D.

    1988-01-01

    Recent results on the use of pulsations in white dwarf stars as seismic probes of their structure are reviewed. The evolution of stars to the white dwarf stage is first described, followed by a discussion of their structure as expected from the theory of stellar evolution. A summary of the salient points of stellar pulsation theory is given and then compared with observations of pulsating white dwarfs: the pulsations are non-radial 'g-mode' pulsations and occur in all white dwarfs as they cool through the temperature ranges defining each of the four 'instability strips' on the white dwarf cooling curve. The presence of only some of the possible pulsation modes in any given star suggest that a filter mechanism to select these modes is at work, possibly the chemical stratification of the star. The pulsation periods can be measured very accurately so that period changes, due to evolutionary cooling, can be detected over relatively short intervals (2 - 30 years). The detection of such period changes can be used to place interesting limits on the age of the Galaxy and ultimately the age of the Universe. 17 refs., 10 figs., 2 tabs

  7. Study of white noise; Hakushoku zatsuon ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kano, R; Tada, R [Teikoku Oil Co. Ltd., Tokyo (Japan)

    1996-05-01

    A study was made on conditions available for white noise belonging to a finite power function with the use of a power spectrum conception. It was defined that a real variable function with a finite waveform energy was a finite energy function while that with a finite waveform power was a finite power function. A noncorrelative white noise was defined as a real variable function in which an autocorrelation function took a specific value at a certain point; however, the autocorrelation function was different between the finite energy function and the finite power function. In other words, the definition of white noise was such that `an energy spectrum was a fixed value` in the finite energy function, and that `a power spectrum was a fixed value` in the finite power function. It was pointed out, by Matsuyama (1994) with the use of the energy spectrum conception, that the white noise belonging to the finite energy function took only the form of `an arbitrary impulse function that all turned to zero except a certain point`. The same conclusion was obtained with respect to the white noise belonging to the finite power function. 1 ref., 1 tab.

  8. Birth weight trends among interracial black and white infants.

    Science.gov (United States)

    Parker, J D

    2000-05-01

    I examined time trends in low birth weight (LBW) and very low birth weight (VLBW) among interracial compared with single-race infants. Using natality data from 1978 through 1997 for singleton births to black and white parents, I calculated relative risks (RRs) of LBW and VLBW for interracial compared with single-race births, stratified by maternal race and adjusted for maternal characteristics. Among black mothers, interracial births had lower risks of LBW and VLBW than single-race births, and RRs were similar throughout the time period [for example, adjusted RR = 0.76 and 95% confidence interval (CI) = 0.73-0.80 for LBW in 1994-1997]. Among white mothers, interracial infants had higher risks of LBW than single-race infants; however, the adjusted RRs declined over the time period, from 1.22 (95% CI = 1.19-1.27) in 1978-1981 to 1.05 (95% CI = 1.03-1.08) in 1994-1997. Since 1978, there has been some relative improvement in birth outcomes for infants of white mothers and black fathers compared with single-race white births. There was, however, no relative improvement for black mother/black father infants relative to black mother/white father births.

  9. White Nights rebuts Pravda claims

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports that another Russo-foreign joint venture under attack in the Moscow press has denied charges of impropriety and mismanagement in its operations. The White Nights joint venture last month came under scathing attack from Moscow newspaper Pravda, which alleged the venture has reneged on its promises, is virtually bankrupt, and mistreats Russian employees. White Nights is a joint venture owned 50% by Varyeganneftegaz (VNG), a Russian oil and gas enterprise, and 50% by Salomon Inc. unit Phibro Energy Inc., Greenwich, Conn., and Anglo-Suisse (U.S.S.R.) Ltd., a subsidiary of Anglo-Suisse Inc., Houston. The venture started operations Apr. 1, 1991, with a program of workovers, redevelopment, and horizontal wells in West Varyegan and Tagrinsk oil fields in western Siberia

  10. A Dark Spot on a Massive White Dwarf

    Science.gov (United States)

    Kilic, Mukremin; Gianninas, Alexandros; Bell, Keaton J.; Curd, Brandon; Brown, Warren R.; Hermes, J. J.; Dufour, Patrick; Wisniewski, John P.; Winget, D. E.; Winget, K. I.

    2015-12-01

    We present the serendipitous discovery of eclipse-like events around the massive white dwarf SDSS J152934.98+292801.9 (hereafter J1529+2928). We selected J1529+2928 for time-series photometry based on its spectroscopic temperature and surface gravity, which place it near the ZZ Ceti instability strip. Instead of pulsations, we detect photometric dips from this white dwarf every 38 minutes. Follow-up optical spectroscopy observations with Gemini reveal no significant radial velocity variations, ruling out stellar and brown dwarf companions. A disintegrating planet around this white dwarf cannot explain the observed light curves in different filters. Given the short period, the source of the photometric dips must be a dark spot that comes into view every 38 minutes due to the rotation of the white dwarf. Our optical spectroscopy does not show any evidence of Zeeman splitting of the Balmer lines, limiting the magnetic field strength to B Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).

  11. White LED with High Package Extraction Efficiency

    International Nuclear Information System (INIS)

    Yi Zheng; Stough, Matthew

    2008-01-01

    The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W e using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated

  12. White balance tester with color sensor for industrial applications

    Science.gov (United States)

    Chen, Jiasheng; Zhu, XiaoSong

    1996-12-01

    The white balance tester is an instrument that adjusts the white balance for color TVs, monitors, and PC displays. We have designed a new white balance tester for use directly at the production line. It picks up the R (Red), G (Green), and B (Blue) signals for the screen using color sensors, compares the signals with the data previously stored in the internal memory, displays their differences with LED bars in the compare mode or displays x y Y, u v Y, JND (just noticeable difference) as well as correlated color temperature in the numerical mode. A built-in TV signal generator sets the luminance of the adjusting screen to the brightness of the reference white screen automatically. A 16-bit single chip microcomputer processes the measured values and controls the output levels of the TV signal generator.

  13. Is humane slaughter of fish possible for industry?

    NARCIS (Netherlands)

    Vis, van de J.W.; Kestin, S.; Robb, D.; Oehlenschlaeger, J.; Lambooij, E.; Kuhlmann, H.; Kloosterboer, K.

    2003-01-01

    The objective was to evaluate industrial and research slaughter methods for Atlantic salmon (Salmo salar), gilt-head seabream (Sparus auratus) and eel (Anguilla anguilla) with respect to welfare and quality. As a general term of reference, an optimal slaughter method should render fish unconscious

  14. White matter integrity in kleptomania: A pilot study

    Science.gov (United States)

    Grant, Jon E.; Correia, Stephen; Brennan-Krohn, Thea

    2007-01-01

    This study's goal was to examine microstructural organization of frontal white matter in kleptomania. Ten females with DSM-IV kleptomania and 10 female controls underwent diffusion tensor imaging. Inferior frontal white matter was the a priori region of interest. Trace and fractional anisotropy (FA) were also calculated for frontal and posterior cortical regions in both subject groups. Kleptomania subjects had significantly higher mean frontal Trace, and significantly lower mean frontal FA than control subjects. Group differences remained significant when right and left frontal Trace and FA were analyzed. Groups did not differ significantly in posterior Trace or FA. Kleptomania may be associated with decreased white matter microstructural integrity in inferior frontal brain regions. PMID:16956753

  15. WHITE COLLAR CRIME - Investigations

    OpenAIRE

    Nyagudi, Nyagudi Musandu

    2014-01-01

    WHITE COLLAR CRIME - Investigations Presentation By  Dr. Nyagudi MusanduForensic Criminologist 2nd International Securityand Safety Conference and Exhibition, 16th April, 2010 a forum hosted by Events Management Solutions at the Sarit Centre, Nairobi, Kenya  

  16. The search for the white Nordic

    DEFF Research Database (Denmark)

    Andreassen, Rikke

    2014-01-01

    arrived immigrants and descendants. The article includes an analysis of Nordic race science from the turn of the twentieth century in order to illustrate how the New Nordic Kitchen draws upon a longer historical tradition of viewing the Nordic, and especially Nordic whiteness, as superior. The historical...... importance of race science in Denmark is not common knowledge, and very limited research is done in this area. The article therefore also brings new insights to the historical construction of whiteness in the Nordic context. Finally, the article also shows how the New Nordic Kitchen not only draws upon...

  17. White light coronagraph in OSO-7

    International Nuclear Information System (INIS)

    Koomen, M.J.; Detwiler, C.R.; Brueckner, G.E.; Cooper, H.W.; Tousey, R.

    1975-01-01

    A small, externally occulted Lyot-type coronagraph, designated for use in the seventh unmanned Orbiting Solar Observatory (OSO-7), is described. Optical configuration, suppression of stray light, SEC vidicon detector, and data system are discussed, as well as integration of the instrument into the spacecraft and operation in orbit. Orbital operation produced daily images of the white light corona, from 2.8 to 10 solar radii, at least once per day for 2 3/4 yr. The first records of white light coronal transient events were obtained, and the corona was shown to be constantly changing

  18. Cerebral white matter hypoplasia

    International Nuclear Information System (INIS)

    Dietrich, R.B.; Shields, W.D.; Sankar, R.

    1990-01-01

    This paper demonstrates the MR imaging findings in children with cerebral white matter hypoplasia (CWMH). The MR studies of four children, aged 3-7 y (mean age, 2.3 y) with a diagnosis of CWMH were reviewed. In all cases multiplanar T1-weighted and T2-weighted spin-echo images were obtained. All children had similar histories of severe developmental delay and nonprogressive neurologic deficits despite normal gestational and birth histories. In two cases there was a history of maternal cocaine abuse. Autopsy correlation was available in one child. The MR images of all four children demonstrated diffuse lack of white matter and enlarged ventricles but normal-appearing gray matter. The corpus callosum, although completely formed, was severely thinned. There was no evidence of gliosis or porencephaly, and the distribution of myelin deposition was normal for age in all cases. Autopsy finding in one child correlated exactly with the MR finding

  19. Fate of accreting white dwarfs: Type I supernovae vs collapse

    International Nuclear Information System (INIS)

    Nomoto, Ken'ichi.

    1986-01-01

    The final fate of accreting C + O white dwarfs is either thermonuclear explosion or collapse, if the white dwarf mass grows to the Chandrasekhar mass. We discuss how the fate depends on the initial mass, age, composition of the white dwarf and the mass accretion rate. Relatively fast accretion leads to a carbon deflagration at low central density that gives rise to a Type Ia supernova. Slower accretion induces a helium detonation that could be observed as a Type Ib supernova. If the initial mass of the C + O white dwarf is larger than 1.2 Msub solar, a carbon deflagration starts at high central density and induces a collapse of the white dwarf to form a neutron star. We examine the critical condition for which a carbon deflagration leads to collapse, not explosion. For the case of explosion, we discuss to what extent the nucleosynthesis models are consistent with spectra of Type Ia and Ib supernovae. 61 refs., 18 figs

  20. Possibilities of breeding weevil-resistant white pine strains

    Science.gov (United States)

    Jonathan W. Wright; William J. Gabriel

    1959-01-01

    Eastern white pine (Pinus strobus L.) is a highly versatile species. It is easily planted, adaptable to a wide variety of soils and climates, and reproduces itself well. Also it grows rapidly and is capable of producing high-quality lumber. These characteristics once entitled white pine to a top position in the forest economy throughout much of the...

  1. Silvical characteristics of Atlantic white-cedar (Chamaecyparis thyoides)

    Science.gov (United States)

    S. Little

    1959-01-01

    Atlantic white-cedar ((Chamaecyparis thyoides (L.) B.S.P.) has been a highly prized species since Colonial times because of the durability and high quality of its wood. The wood has been used for many purposes: boat boards, shingles and lath, framing, house and boat finish, pails and tanks, cabin logs, posts, and poles. Good white-cedar has always...

  2. White Dwarf Stars

    Science.gov (United States)

    1999-01-01

    Peering deep inside a cluster of several hundred thousand stars, NASA's Hubble Space Telescope has uncovered the oldest burned-out stars in our Milky Way Galaxy, giving astronomers a fresh reading on the age of the universe. Located in the globular cluster M4, these small, burned-out stars -- called white dwarfs -- are about 12 to 13 billion years old. By adding the one billion years it took the cluster to form after the Big Bang, astronomers found that the age of the white dwarfs agrees with previous estimates that the universe is 13 to 14 billion years old. The images, including some taken by Hubble's Wide Field and Planetary Camera 2, are available online at http://oposite.stsci.edu/pubinfo/pr/2002/10/ or http://www.jpl.nasa.gov/images/wfpc . The camera was designed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif. In the top panel, a ground-based observatory snapped a panoramic view of the entire cluster, which contains several hundred thousand stars within a volume of 10 to 30 light-years across. The Kitt Peak National Observatory's .9-meter telescope took this picture in March 1995. The box at left indicates the region observed by the Hubble telescope. The Hubble telescope studied a small region of the cluster. A section of that region is seen in the picture at bottom left. A sampling of an even smaller region is shown at bottom right. This region is only about one light-year across. In this smaller region, Hubble pinpointed a number of faint white dwarfs. The blue circles indicate the dwarfs. It took nearly eight days of exposure time over a 67-day period to find these extremely faint stars. Globular clusters are among the oldest clusters of stars in the universe. The faintest and coolest white dwarfs within globular clusters can yield a globular cluster's age. Earlier Hubble observations showed that the first stars formed less than 1 billion years after the universe's birth in the big bang. So, finding the oldest stars puts astronomers within

  3. In vivo evidence of cerebellar atrophy and cerebral white matter loss in Huntington disease

    DEFF Research Database (Denmark)

    Fennema-Notestine, C; Archibald, S.L.; Jacobsen, M.W.

    2004-01-01

    and education. Primary analyses defined six subcortical regions, the gray and white matter of primary cortical lobes and cerebellum, and abnormal signal in the cerebral white matter. RESULTS: As expected, basal ganglia and cerebral cortical gray matter volumes were significantly smaller in HD. The HD group also...... demonstrated significant cerebral white matter loss and an increase in the amount of abnormal signal in the white matter; occipital white matter appeared more affected than other cerebral white matter regions. Cortical gray and white matter measures were significantly related to caudate volume. Cerebellar gray...

  4. 3 CFR - White House Task Force on Middle-Class Working Families

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false White House Task Force on Middle-Class Working Families Presidential Documents Other Presidential Documents Memorandum of January 30, 2009 White House... times. To these ends, I hereby direct the following: Section 1. White House Task Force on Middle-Class...

  5. Study on the sterilization of egg white powder by irradiation

    International Nuclear Information System (INIS)

    Fu Lixin; Meng Lifen; Zhao Xiaonan; Xu Dechun; Hu Shaoxin; Chen Changdong; Wang Zhidong

    2013-01-01

    The sterilizing effect, influence on main essential nutrient and sensory qualities of egg white powder treated with 60 Co γ-ray irradiation were studied. The microorganism index of egg white powder samples treated with 4 kGy irradiation could meet the government food sanitation standard, and the sterilization rate could reach 100%. The irradiation doses from 4 to 10 kGy had little influence on egg white powder protein, crude fiber and amino acidscontent, and the sensory quality such as color, luster, and scent changed little below 6 kGy irradiation. Considering the result of this study, the optimal irradiation dose for egg white powder sterilization was 4 to 6 kGy. (authors)

  6. White Rose development plan amendment production volume increase

    International Nuclear Information System (INIS)

    2006-09-01

    In January 2001, Husky Oil Operations Limited (Husky), in joint-venture with Petro-Canada, submitted a Benefits Plan for the White Rose Development to the Canada- Newfoundland and Labrador Offshore Petroleum Board (C-NLOPB). This revised document provided the case for requesting an increase in the facility maximum daily production rate and the average annual production rate for the White Rose field from 100,000 barrels per day (bpd) as stated in the approved White Rose Development Plan to 140,000 bpd. In order to determine the potential for increasing oil production through the Floating Production, Storage and Offloading (FPSO) vessel, two things were considered, namely the proper reservoir management of the White Rose field to ensure optimum resource recovery, and the capacity of the FPSO topsides processing system and supporting utilities to accommodate increased production. This document presented a detailed review of all the implications of increased production on the South White Rose Reservoir. In addition, the results from FPSO performance testing were reviewed, including a study of options for de-bottlenecking the process plant on the topsides and capacity testing of selected process streams and support systems. Vibration analysis was conducted before and during performance testing in July 2006 and a small number of areas addressed. The document also addressed flow metering, resource management, certifying authority review, safety plan revisions, environmental effects, as well as benefits to Canada and Newfoundland. 21 tabs., 60 refs

  7. Cigarette smoking is associated with reduced microstructural integrity of cerebral white matter.

    Science.gov (United States)

    Gons, Rob A R; van Norden, Anouk G W; de Laat, Karlijn F; van Oudheusden, Lucas J B; van Uden, Inge W M; Zwiers, Marcel P; Norris, David G; de Leeuw, Frank-Erik

    2011-07-01

    Cigarette smoking doubles the risk of dementia and Alzheimer's disease. Various pathophysiological pathways have been proposed to cause such a cognitive decline, but the exact mechanisms remain unclear. Smoking may affect the microstructural integrity of cerebral white matter. Diffusion tensor imaging is known to be sensitive for microstructural changes in cerebral white matter. We therefore cross-sectionally studied the relation between smoking behaviour (never, former, current) and diffusion tensor imaging parameters in both normal-appearing white matter and white matter lesions as well as the relation between smoking behaviour and cognitive performance. A structured questionnaire was used to ascertain the amount and duration of smoking in 503 subjects with small-vessel disease, aged between 50 and 85 years. Cognitive function was assessed with a neuropsychological test battery. All subjects underwent 1.5 Tesla magnetic resonance imaging. Using diffusion tensor imaging, fractional anisotropy and mean diffusivity were calculated in both normal-appearing white matter and white matter lesions. A history of smoking was associated with significant higher values of mean diffusivity in normal-appearing white matter and white matter lesions (P-trend for smoking status = 0.02) and with poorer cognitive functioning compared with those who never smoked. Associations with smoking and loss of structural integrity appeared to be strongest in normal-appearing white matter. Furthermore, the duration of smoking cessation was positively related to lower values of mean diffusivity and higher values of fractional anisotropy in normal-appearing white matter [β = -0.004 (95% confidence interval -0.007 to 0.000; P = 0.03) and β = 0.019 (95% confidence interval 0.001-0.038; P = 0.04)]. Fractional anisotropy and mean diffusivity values in normal-appearing white matter of subjects who had quit smoking for >20 years were comparable with subjects who had never smoked. These data suggest

  8. Differences from somewhere: the normativity of whiteness in bioethics in the United States.

    Science.gov (United States)

    Myser, Catherine

    2003-01-01

    I argue that there has been inadequate attention to and questioning of the dominance and normativity of whiteness in the cultural construction of bioethics in the United States. Therefore we risk reproducing white privilege and white supremacy in its theory, method, and practices. To make my argument, I define whiteness and trace its broader social and legal history in the United States. I then begin to mark whiteness in U.S. bioethics, recasting Renee Fox's sociological marking of its American-ness as an important initial marking of its whiteness/WASP ethos. Furthermore, I consider the attempts of social scientists to highlight sociocultural diversity as a corrective in U.S. bioethics. I argue that because they fail to problematize white dominance and normativity and the white-other dualism when they describe the standpoints of African-American, Asian-American, and Native-American others, their work merely inoculates difference and creates or maintains minoritized spaces. Accordingly, the dominant white center of mainstream U.S. bioethics must be problematized and displaced for diversity research to make a difference. In conclusion, I give several examples of how we might advance the recommended endeavor of exploring our own ethnicity, class, and other social positioning and norms operating in U.S. bioethics, briefly highlighting "white talk" as one challenge.

  9. White matter hypoperfusion and damage in dementia: post-mortem assessment.

    Science.gov (United States)

    Love, Seth; Miners, J Scott

    2015-01-01

    Neuroimaging has revealed a range of white matter abnormalities that are common in dementia, some that predict cognitive decline. The abnormalities may result from structural diseases of the cerebral vasculature, such as arteriolosclerosis and amyloid angiopathy, but can also be caused by nonstructural vascular abnormalities (eg, of vascular contractility or permeability), neurovascular instability or extracranial cardiac or vascular disease. Conventional histopathological assessment of the white matter has tended to conflate morphological vascular abnormalities with changes that reflect altered interstitial fluid dynamics or white matter ischemic damage, even though the latter may be of extracranial or nonstructural etiology. However, histopathology is being supplemented by biochemical approaches, including the measurement of proteins involved in the molecular responses to brain ischemia, myelin proteins differentially susceptible to ischemic damage, vessel-associated proteins that allow rapid measurement of microvessel density, markers of blood-brain barrier dysfunction and axonal injury, and mediators of white matter damage. By combining neuroimaging with histopathology and biochemical analysis, we can provide reproducible, quantitative data on the severity of white matter damage, and information on its etiology and pathogenesis. Together these have the potential to inform and improve treatment, particularly in forms of dementia to which white matter hypoperfusion makes a significant contribution. © 2014 International Society of Neuropathology.

  10. Testing the white dwarf mass-radius relationship with eclipsing binaries

    Science.gov (United States)

    Parsons, S. G.; Gänsicke, B. T.; Marsh, T. R.; Ashley, R. P.; Bours, M. C. P.; Breedt, E.; Burleigh, M. R.; Copperwheat, C. M.; Dhillon, V. S.; Green, M.; Hardy, L. K.; Hermes, J. J.; Irawati, P.; Kerry, P.; Littlefair, S. P.; McAllister, M. J.; Rattanasoon, S.; Rebassa-Mansergas, A.; Sahman, D. I.; Schreiber, M. R.

    2017-10-01

    We present high-precision, model-independent, mass and radius measurements for 16 white dwarfs in detached eclipsing binaries and combine these with previously published data to test the theoretical white dwarf mass-radius relationship. We reach a mean precision of 2.4 per cent in mass and 2.7 per cent in radius, with our best measurements reaching a precision of 0.3 per cent in mass and 0.5 per cent in radius. We find excellent agreement between the measured and predicted radii across a wide range of masses and temperatures. We also find the radii of all white dwarfs with masses less than 0.48 M⊙ to be fully consistent with helium core models, but they are on average 9 per cent larger than those of carbon-oxygen core models. In contrast, white dwarfs with masses larger than 0.52 M⊙ all have radii consistent with carbon-oxygen core models. Moreover, we find that all but one of the white dwarfs in our sample have radii consistent with possessing thick surface hydrogen envelopes (10-5 ≥ MH/MWD ≥ 10-4), implying that the surface hydrogen layers of these white dwarfs are not obviously affected by common envelope evolution.

  11. Mapping White Matter Microstructure in the One Month Human Brain.

    Science.gov (United States)

    Dean, D C; Planalp, E M; Wooten, W; Adluru, N; Kecskemeti, S R; Frye, C; Schmidt, C K; Schmidt, N L; Styner, M A; Goldsmith, H H; Davidson, R J; Alexander, A L

    2017-08-29

    White matter microstructure, essential for efficient and coordinated transmission of neural communications, undergoes pronounced development during the first years of life, while deviations to this neurodevelopmental trajectory likely result in alterations of brain connectivity relevant to behavior. Hence, systematic evaluation of white matter microstructure in the normative brain is critical for a neuroscientific approach to both typical and atypical early behavioral development. However, few studies have examined the infant brain in detail, particularly in infants under 3 months of age. Here, we utilize quantitative techniques of diffusion tensor imaging and neurite orientation dispersion and density imaging to investigate neonatal white matter microstructure in 104 infants. An optimized multiple b-value diffusion protocol was developed to allow for successful acquisition during non-sedated sleep. Associations between white matter microstructure measures and gestation corrected age, regional asymmetries, infant sex, as well as newborn growth measures were assessed. Results highlight changes of white matter microstructure during the earliest periods of development and demonstrate differential timing of developing regions and regional asymmetries. Our results contribute to a growing body of research investigating the neurobiological changes associated with neurodevelopment and suggest that characteristics of white matter microstructure are already underway in the weeks immediately following birth.

  12. The chemical evolution of white dwarf atmospheres: Diffusion and accretion

    International Nuclear Information System (INIS)

    Vauclair, G.; Vauclair, S.; Greenstein, J.L.

    1979-01-01

    A study of diffusion processes in white dwarfs is presented. We are especially interested in the estimate of the diffusion time scales for C, N, O, Mg, and Ca along the cooling sequence. The effect of the radiative acceleration is important in hot white dwarfs while in cooler ones the thermal diffusion dominates the gravitational settling. In hot white dwarfs, there should be an observable amount of CNO elements unless they have previously left the stars by a selective wind. Observational tests of this result are discussed. The diffusion time scales are always short compared to the evolutionary time scales. It is shown that in both hydrogen and helium envelopes, the convection zone, even at its maximum depth, is not able to bring back to the stellar surface the metals which have previously diffused downwards. The diffusion alone predicts a complete absence of metals in white dwarf atmospheres and envelopes. As metals are observed in white dwarfs, at least at effective temperatures lower than 15,000 K, there must be some mechanism competing with diffusion. We investigate the competition between diffusion and accretion and propose a general scheme for the chemical evolution of white dwarf atmospheres along the cooling sequence. (orig.)

  13. Evolutionary-Optimized Photonic Network Structure in White Beetle Wing Scales.

    Science.gov (United States)

    Wilts, Bodo D; Sheng, Xiaoyuan; Holler, Mirko; Diaz, Ana; Guizar-Sicairos, Manuel; Raabe, Jörg; Hoppe, Robert; Liu, Shu-Hao; Langford, Richard; Onelli, Olimpia D; Chen, Duyu; Torquato, Salvatore; Steiner, Ullrich; Schroer, Christian G; Vignolini, Silvia; Sepe, Alessandro

    2018-05-01

    Most studies of structural color in nature concern periodic arrays, which through the interference of light create color. The "color" white however relies on the multiple scattering of light within a randomly structured medium, which randomizes the direction and phase of incident light. Opaque white materials therefore must be much thicker than periodic structures. It is known that flying insects create "white" in extremely thin layers. This raises the question, whether evolution has optimized the wing scale morphology for white reflection at a minimum material use. This hypothesis is difficult to prove, since this requires the detailed knowledge of the scattering morphology combined with a suitable theoretical model. Here, a cryoptychographic X-ray tomography method is employed to obtain a full 3D structural dataset of the network morphology within a white beetle wing scale. By digitally manipulating this 3D representation, this study demonstrates that this morphology indeed provides the highest white retroreflection at the minimum use of material, and hence weight for the organism. Changing any of the network parameters (within the parameter space accessible by biological materials) either increases the weight, increases the thickness, or reduces reflectivity, providing clear evidence for the evolutionary optimization of this morphology. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Testing the initial-final mass relationship of white dwarfs

    International Nuclear Information System (INIS)

    Catalan, S; Isern, J; Garcia-Berro, E; Ribas, I

    2009-01-01

    In this contribution we revisit the initial-final mass relationship of white dwarfs, which links the mass of a white dwarf with that of its progenitor in the main-sequence. Although this function is of paramount importance to several fields in modern astrophysics, it is still not well constrained either from the theoretical or the observational points of view. We present here a revision of the present semi-empirical initial-final mass relationship using all the available data and including our recent results obtained from studying white dwarfs in common proper motion pairs. We have also analyzed the results obtained so far to provide some clues on the dependence of this relationship on metallicity. Finally, we have also performed an indirect test of the initial-final mass relationship by studying its effect on the luminosity function and on the mass distribution of white dwarfs.

  15. Genetic disorders affecting white matter in the pediatric age.

    Science.gov (United States)

    Di Rocco, Maja; Biancheri, Roberta; Rossi, Andrea; Filocamo, Mirella; Tortori-Donati, Paolo

    2004-08-15

    Pediatric white matter disorders can be distinguished into well-defined leukoencephalopathies, and undefined leukoencephalopathies. The first category may be subdivided into: (a) hypomyelinating disorders; (b) dysmyelinating disorders; (c) leukodystrophies; (d) disorders related to cystic degeneration of myelin; and (e) disorders secondary to axonal damage. The second category, representing up to 50% of leukoencephalopathies in childhood, requires a multidisciplinar approach in order to define novel homogeneous subgroups of patients, possibly representing "new genetic disorders" (such as megalencephalic leukoencepahlopathy with subcortical cysts and vanishing white matter disease that have recently been identified). In the majority of cases, pediatric white matter disorders are inherited diseases. An integrated description of the clinical, neuroimaging and pathophysiological features is crucial for categorizing myelin disorders and better understanding their genetic basis. A review of the genetic disorders affecting white matter in the pediatric age, including some novel entities, is provided. Copyright 2004 Wiley-Liss, Inc.

  16. White House Tapes of the Nixon Administration, 1971 to 1973

    Data.gov (United States)

    National Archives and Records Administration — This dataset provides information about the Nixon Administration's White House Tapes. The White House Tapes contain sound recordings of President Richard Nixon's...

  17. High-Resolution EUV Spectroscopy of White Dwarfs

    Science.gov (United States)

    Kowalski, Michael P.; Wood, K. S.; Barstow, M. A.

    2014-01-01

    We compare results of high-resolution EUV spectroscopic measurements of the isolated white dwarf G191-B2B and the binary system Feige 24 obtained with the J-PEX (Joint Plasmadynamic Experiment), which was sponsored jointly by the U.S. Naval Research Laboratory and NASA. J-PEX delivers the world's highest resolution in EUV and does so at high effective area (e.g., more effective area in a sounding rocket than is available with Chandra at adjacent energies, but in a waveband Chandra cannot reach). The capability J-PEX represents is applicable to the astrophysics of hot plasmas in stellar coronae, white dwarfs and the ISM. G191-B2B and Feige 24 are quite distinct hot white dwarf systems having in common that they are bright in the portion of the EUV where He emission features and edges occur, hence they can be exploited to probe both the stellar atmosphere and the ISM, separating those components by model-fitting that sums over all relevant (He) spectral features in the band. There is evidence from these fits that atmospheric He is being detected but the result is more conservatively cast as a pair of upper limits. We discuss how longer duration satellite observations with the same instrumentation could increase exposure to detect atmospheric He in these and other nearby hot white dwarfs.

  18. The 25 parsec local white dwarf population

    Science.gov (United States)

    Holberg, J. B.; Oswalt, T. D.; Sion, E. M.; McCook, G. P.

    2016-11-01

    We have extended our detailed survey of the local white dwarf population from 20 to 25 pc, effectively doubling the sample volume, which now includes 232 stars. In the process, new stars within 20 pc have been added, a more uniform set of distance estimates as well as improved spectral and binary classifications are available. The present 25 pc sample is estimated to be about 68 per cent complete (the corresponding 20 pc sample is now 86 per cent complete). The space density of white dwarfs is unchanged at 4.8 ± 0.5 × 10-3 pc-3. This new study includes a white dwarf mass distribution and luminosity function based on the 232 stars in the 25 pc sample. We find a significant excess of single stars over systems containing one or more companions (74 per cent versus 26 per cent). This suggests mechanisms that result in the loss of companions during binary system evolution. In addition, this updated sample exhibits a pronounced deficiency of nearby `Sirius-like' systems. 11 such systems were found within the 20 pc volume versus only one additional system found in the volume between 20 and 25 pc. An estimate of white dwarf birth rates during the last ˜8 Gyr is derived from individual remnant cooling ages. A discussion of likely ways new members of the local sample may be found is provided.

  19. Moessbauer spectra of white micas from the Central Western Carpathians Mountains

    International Nuclear Information System (INIS)

    Sitek, J; Toth, I; Sulak, M; Putis, M

    2010-01-01

    Potassium white micas from the rocks included into Cretaceous deformation zones (ca. 100-70 Ma in age) of the Central Western Carpathians were investigated by Moessbauer spectroscopy. White micas formed during a polystage evolution and changing P-T conditions of their crystallization in crustal-scale shear zones. We found criteria for distinguishing generations of celadonite-poor (muscovitic) and celadonite-rich (phengitic) white micas using Moessbauer spectroscopy. This method revealed contrasting spectra characterized by typical quadrupole doublets corresponding to Fe 2+ Fe 3+ contents in white micas. They are in the range of 2.9-3.0 mm/s for phengite, and 2.6-2.7 mm/s for muscovite. Moessbauer spectra reflect well the chemical changes in white mica aggregates, especially of those close to the end-member muscovite and (alumino-)celadonite compositions.

  20. Moessbauer spectra of white micas from the Central Western Carpathians Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Sitek, J; Toth, I [Department of Nuclear Physics and Technology, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkovicova 3, Bratislava (Slovakia); Sulak, M; Putis, M, E-mail: jozef.sitek@stuba.s [Department of of Mineralogy and Petrology, Faculty of Natural Sciences, Comenius University Bratislava, Mlynska dolina G, 842 15 Bratislava (Slovakia)

    2010-03-01

    Potassium white micas from the rocks included into Cretaceous deformation zones (ca. 100-70 Ma in age) of the Central Western Carpathians were investigated by Moessbauer spectroscopy. White micas formed during a polystage evolution and changing P-T conditions of their crystallization in crustal-scale shear zones. We found criteria for distinguishing generations of celadonite-poor (muscovitic) and celadonite-rich (phengitic) white micas using Moessbauer spectroscopy. This method revealed contrasting spectra characterized by typical quadrupole doublets corresponding to Fe{sup 2+} Fe{sup 3+} contents in white micas. They are in the range of 2.9-3.0 mm/s for phengite, and 2.6-2.7 mm/s for muscovite. Moessbauer spectra reflect well the chemical changes in white mica aggregates, especially of those close to the end-member muscovite and (alumino-)celadonite compositions.