Science.gov

Sample records for highly exposed group

  1. Brucellosis in Occupationally Exposed Groups

    PubMed Central

    Sajjan, Annapurna G.; Mohite, Shivajirao T.; Gajul, Shivali

    2016-01-01

    Introduction In India, high incidence of human brucellosis may be expected, as the conditions conducive for human brucellosis exist. Limited studies have been undertaken on human brucellosis especially in occupationally-exposed groups. Aim To estimate prevalence of anti-brucellar antibodies, evaluate the clinical manifestations, risk factors and Knowledge, Attitude and Practices (KAP) levels about brucellosis among occupationally exposed groups. Materials and Methods Blood samples were collected from 2337 occupationally exposed individuals. The serum samples were screened for the presence of anti-brucellar antibodies by Rose Bengal Plate Test (RBPT), Serum Agglutination Test (SAT) and 2-Mercaptoethanol test (2-ME). Clinical manifestations, risk factors and KAP levels were evaluated by personal interview using a structured questionnaire. Results Seroprevalence of brucellosis by RBPT, SAT and 2-ME test was 9.46%, 4.45% and 3.64 % respectively. Clinical symptoms resembling brucellosis were seen in 91 subjects. The major risk factors were animal exposure in veterinarians and abattoirs, both animal exposure and raw milk ingestion in farmers and shepherds, exposure to raw milk and its ingestion in dairy workers and exposure to Brucella culture in laboratory workers. Except laboratory workers, few veterinarians and dairy workers none had heard about brucellosis. KAP levels regarding brucellosis were too poor in all the groups except laboratory workers. Conclusion Brucellosis most of the times was missed or misdiagnosed. Regular screenings for brucellosis and awareness programmes to increase KAP levels are necessary to control brucellosis in occupationally exposed groups. PMID:27190804

  2. Grouped exposed metal heaters

    SciTech Connect

    Vinegar, Harold J.; Coit, William George; Griffin, Peter Terry; Hamilton, Paul Taylor; Hsu, Chia-Fu; Mason, Stanley Leroy; Samuel, Allan James; Watkins, Ronnie Wade

    2012-07-31

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  3. Grouped exposed metal heaters

    DOEpatents

    Vinegar, Harold J.; Coit, William George; Griffin, Peter Terry; Hamilton, Paul Taylor; Hsu, Chia-Fu; Mason, Stanley Leroy; Samuel, Allan James; Watkins, Ronnie Wade

    2010-11-09

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  4. Subject groups high and low in urinary selenium levels: workers exposed to heavy metals and patients with cancer and epilepsy

    SciTech Connect

    Hojo, Y.

    1981-04-01

    Selenium was first recognized for its toxicity; its essential nature in animals was discovered and established later. That Se is essential to human nutrition has yet to be confirmed. Recently the selenoenzyme glutathione peroxidase (GSH-Px) was isolated from human erythrocyte and placenta. In order to discover the role Se plays in human health and disease, Thomson and Robinson emphasized a need for continuing studies of special needs of certain groups such as those exposed to heavy metals and those with certain disease and illness for example, cancer and cardiovascular disease. It is amongst these groups that Se deficiency or Se-responsive conditions may be found. Urinary Se excretion has been mainly used to assess the nutritional Se status. Recently estimation of urinary Se level in the form of its content per creatinine (abbreviated as CT) content using 24-h or random urine samples was shown to be more precise in reducing dilution and variation effects than that per urinary volume using 24-h urines (HOJO). The purpose of this study is to search the subject groups high or low in Se status by employing urinary Se content per CT content or per urine volume.

  5. Effects on the nervous system in different groups of workers exposed to aluminium

    PubMed Central

    Iregren, A; Sjogren, B; Gustafsson, K; Hagman, M; Nylen, L; Frech, W; Andersson, M; Ljunggren, K; Wennberg, A

    2001-01-01

    OBJECTIVE—To investigate possible neurotoxic effects in groups of aluminium pot room and foundry workers, aluminium welders, and a small group of workers exposed to aluminium in the production of flake powder.
METHODS—Exposure to aluminium was evaluated with aluminium concentrations in blood and urine as well as a questionnaire. The groups exposed to aluminium were compared with a group of mild steel welders. Neurotoxic effects were studied with mood and symptom questionnaires and several psychological and neurophysiological tests.
RESULTS—The pot room and foundry workers showed very low aluminium uptake as their aluminium concentrations in blood and urine were close to normal, and no effects on the nervous system were detected. The group of workers exposed to flake powder had high concentrations of aluminium in blood and urine, even higher than those of the aluminium welders. However, aluminium could not be shown to affect the functioning of the nervous system in flake powder producers. Although significant effects could not be shown in the present analysis of the data on welders, the performance of the welders exposed to high concentrations of aluminium was affected according to the analyses in the original paper from this group.
CONCLUSIONS—For the pot room and foundry workers no effects related to the exposure to aluminium could be found. For the group of flake powder producers exposed for a short term no effects on the nervous systems were evident despite high levels of exposure. Due to the high concentrations of aluminium in the biological samples of this group, measures to reduce the exposure to aluminium are recommended, as effects on the central nervous system might develop after protracted exposures. However, this assumption needs to be verified in further studies.


Keywords: aluminium; workers; nervous system PMID:11404450

  6. Dose assessment of population groups exposed to elevated radon levels in radioactive Italian spas

    SciTech Connect

    Sciocchetti, G.; Tosti, S.; Baldassini, P.G.; Sarao, R.; Soldano, E.

    1992-12-31

    The natural spring waters on the Isle of Ischia are among the most radioactive in the world. Therapeutic application of these waters, which contain very high radon concentrations, increases the radon exposure of people treated with them. People who live and work at radioactive spas may be good subjects for testing to evaluate detectable biological effects, especially because their exposures will be less influenced by synergistic factors than those of underground miners. The aim of our investigation was to characterize radon exposure for population groups exposed to high radon levels. Our approach takes into account some peculiar requirements of our epidemiological investigations. To obtain representative dose values, workers were classified into groups to obtain significant results suitable for epidemiological pilot studies. Investigations were carried out on the geological aspects of radon sources, environmental parameters, physical and dosimetric factors which influence radon levels, and related exposures in therapeutic facilities in order to model patterns of radon exposures for the various population groups. We inventoried hyper-radioactive springs on the island. We identified workers in radon spas who were exposed to radiation from inhaled radon daughters and retrospectively assessed their radon exposures. Results showed that, under some conditions, spa employees may have been exposed to much higher than usual levels of radon, which produced up to about 60 mSv y{sup -1} effective dose equivalent.

  7. [Neurological findings in a group of children and adolescents exposed and infected by HIV-1].

    PubMed

    Rocha, Cristiane; Gouvêa, Aída; Machado, Daisy; Cunegundes, Kelly; Beltrão, Suênia; Bononi, Fabiana; Succi, Regina Célia

    2005-09-01

    The CNS infection by HIV-1 in infancy could be present immediately after infection or became manifest later. Microcephalia, mental retardation, pyramidal signs, humor and behavioral disorders and antiretroviral therapy complications are common. This is an observational, sectional and descriptive study about findings on neurological examination of 173 patients in a group of children and adolescents infected and exposed to HIV-1 in perinatal period. Most of them had more than one neurological finding or different diagnosis. The more common findings were: encephalopathy, mental retardation, language delay, pyramidal signs, hyporeflexia. The neurological examination was abnormal in 67% of all patients even in seroreverters. We suggest that this group has a high risk to neurological disease and the development of co-morbidity is directly correlated to clinical deterioration by HIV-1 infection.

  8. Nutritional Status among the Children of Age Group 5-14 Years in Selected Arsenic Exposed and Non-Exposed Areas of Bangladesh

    PubMed Central

    Rezaul Karim, Mohammad; Ahmad, Sk. Akhtar

    2014-01-01

    Objective: To assess and compare the nutritional status of children aged 5-14 years in arsenic exposed and non- exposed areas. Materials and methods: It was a cross sectional study conducted on 600 children of age 5-14 years from arsenic exposed and non-exposed areas in Bangladesh. Designed questionnaire and check list were used for collection of data. To estimate BMI necessary anthropometric measurements of the studied children were done. Dietary intakes of the study children were assessed using 24-hours recall method. Results: The difference of socio-economic conditions between the children of exposed area and non-exposed area was not significant. On an average the body mass index was found to be significantly (p < 0.01) lower among the children of arsenic exposed area (49%) in comparison to that of children in non-exposed area (38%). Stunting (p < 0.01), wasting (p < 0.05) and underweight (p < 0.05) were significantly higher in exposed group in comparison to non-exposed group. No significant difference of nutrition intake was found between exposed and non-exposed children as well as thin and normal children. Conclusion: In this study children exposed to arsenic contaminated water were found to be suffered from lower nutritional status. PMID:25530768

  9. General guidelines for medically screening mixed population groups potentially exposed to nerve or vesicant agents

    SciTech Connect

    Watson, A.P.; Munro, N.B.; Sidell, F.R.; Leffingwell, S.S.

    1992-01-01

    A number of state and local planners have requested guidance on screening protocols and have expressed interest in sampling body fluids from exposed or potentially exposed individuals as a means of estimating agent dose. These guidelines have been developed to provide a clear statement that could be used by state and local emergency response personnel in the event of a nerve or vesicant agent incident resulting in off-post contamination; maximum protection from harm is the goal. The assumption is that any population group so exposed would be heterogeneous for age, gender, reproductive status, and state of health.

  10. Temporary variations in chromosomal aberrations in a group of agricultural workers exposed to pesticides.

    PubMed

    Carbonell, E; Valbuena, A; Xamena, N; Creus, A; Marcos, R

    1995-10-01

    The induction of chromosomal aberrations (CA) was studied in the peripheral lymphocytes of 29 male agricultural workers occupationally exposed to several pesticides. To investigate possible exposure-related changes in the frequency of CA, a longitudinal study has been conducted. Two blood samples were taken from each individual: one in a period of high exposure (spring-summer) and the other in a period of lower exposure (autumn-winter). Simultaneously, two matched control groups constituted by 29 and 24 healthy men, without indication of exposure to pesticides, were analysed. During the period of major exposure, the group of agricultural workers showed a significant increase in the frequency of CA, mainly of chromatid-type, when compared to the unexposed control group; nevertheless, this increase in the expression of CA was not found in the period of minor exposure. This finding could indicate that the frequency of CA is related to the intensity of the pesticide exposure, and that CA have a relatively short-life, recovering the control value a few months later. In addition to the cytogenetic analysis, biochemical and haemotological blood parameters were also analysed and no significant variations were detected. PMID:7491130

  11. Determination of exposed sulfhydryl groups in heated beta-lactoglobulin A using IAEDANS and mass spectrometry.

    PubMed

    Kehoe, Joseph J; Brodkorb, André; Mollé, Daniel; Yokoyama, Emilie; Famelart, Marie-Héléne; Bouhallab, Saíd; Morris, Edwin R; Croguennec, Thomas

    2007-08-22

    This paper takes a new approach to determining which sulfhydryl groups are exposed during the heat denaturation of bovine beta-lactoglobulin A. The sulfhydryl groups exposed after heating were blocked with 5-((((2-iodoacetyl)amino)ethyl)amino)naphthalene-1-sulfonic acid (IAEDANS). The results show that IAEDANS is a suitable blocking agent, and its absorbance at 336 nm enabled the quantification of exposed sulfhydryl groups in a mixture of protein species by gel permeation chromatography. Combined with the specific fragmentation of bound IAEDANS by matrix-assisted laser desorption ionization (MALDI) MS/MS in negative ionization mode, this facilitated the identification of peptides that contained blocked cysteines after enzymatic digestion of the protein. During MALDI MS/MS of the peptides, in positive ionization mode, the IAEDANS molecule remained bound to the cysteines, making it possible to identify exactly which cysteine had been exposed after heating. In beta-lactoglobulin A it was found that cysteine 66 and cysteine 160 were predominantly exposed regardless of the length of exposure to heat.

  12. Increased levels of chromosomal aberrations and DNA damage in a group of workers exposed to formaldehyde.

    PubMed

    Costa, Solange; Carvalho, Sandra; Costa, Carla; Coelho, Patrícia; Silva, Susana; Santos, Luís S; Gaspar, Jorge F; Porto, Beatriz; Laffon, Blanca; Teixeira, João P

    2015-07-01

    Formaldehyde (FA) is a commonly used chemical in anatomy and pathology laboratories as a tissue preservative and fixative. Because of its sensitising properties, irritating effects and cancer implication, FA accounts probably for the most important chemical-exposure hazard concerning this professional group. Evidence for genotoxic effects and carcinogenic properties in humans is insufficient and conflicting, particularly in regard to the ability of inhaled FA to induce toxicity on other cells besides first contact tissues, such as buccal and nasal cells. To evaluate the effects of exposure to FA in human peripheral blood lymphocytes, a group of 84 anatomy pathology laboratory workers exposed occupationally to FA and 87 control subjects were tested for chromosomal aberrations (CAs) and DNA damage (comet assay). The level of exposure to FA in the workplace air was evaluated. The association between genotoxicity biomarkers and polymorphic genes of xenobiotic-metabolising and DNA repair enzymes were also assessed. The estimated mean level of FA exposure was 0.38±0.03 ppm. All cytogenetic endpoints assessed by CAs test and comet assay % tail DNA (%TDNA) were significantly higher in FA-exposed workers compared with controls. Regarding the effect of susceptibility biomarkers, results suggest that polymorphisms in CYP2E1 and GSTP1 metabolic genes, as well as, XRCC1 and PARP1 polymorphic genes involved in DNA repair pathways are associated with higher genetic damage in FA-exposed subjects. Data obtained in this study show a potential health risk situation of anatomy pathology laboratory workers exposed to FA (0.38 ppm). Implementation of security and hygiene measures may be crucial to decrease risk. The obtained information may also provide new important data to be used by health care programs and by governmental agencies responsible for occupational health and safety.

  13. Biosphere Dose Conversion Factors for Reasonably Maximally Exposed Individual and Average Member of Critical Group

    SciTech Connect

    K. Montague

    2000-02-23

    The purpose of this calculation is to develop additional Biosphere Dose Conversion Factors (BDCFs) for a reasonably maximally exposed individual (RMEI) for the periods 10,000 years and 1,000,000 years after the repository closure. In addition, Biosphere Dose Conversion Factors for the average member of a critical group are calculated for those additional radionuclides postulated to reach the environment during the period after 10,000 years and up to 1,000,000 years. After the permanent closure of the repository, the engineered systems within the repository will eventually lose their abilities to contain radionuclide inventory, and the radionuclides will migrate through the geosphere and eventually enter the local water table moving toward inhabited areas. The primary release scenario is a groundwater well used for drinking water supply and irrigation, and this calculation takes these postulated releases and follows them through various pathways until they result in a dose to either a member of critical group or a reasonably maximally exposed individual. The pathways considered in this calculation include inhalation, ingestion, and direct exposure.

  14. Immune response to a potyvirus with exposed amino groups available for chemical conjugation

    PubMed Central

    2012-01-01

    Background The amino terminus of the tobacco etch virus (TEV) capsid protein is located on the external surface of infectious TEV particles, as proposed by previous studies and an in silico model. The epsilon amino groups on the exposed lysine residues are available for chemical conjugation to any given protein, and can thus act as antigen carriers. The availability of amino groups on the surfaces of TEV particles was determined and the immune response to TEV evaluated. Results Using a biotin-tagged molecule that reacts specifically with amino groups, we found that the TEV capsid protein has amino groups on its surface available for coupling to other molecules via crosslinkers. Intraperitoneal TEV was administered to female BALB/c mice, and both their humoral and cellular responses measured. Different IgG isotypes, particularly IgG2a, directed against TEV were induced. In a cell proliferation assay, only spleen cells from vaccinated mice that were stimulated in vitro with TEV showed significant proliferation of CD3+/CD4+ and CD3+/CD8+ subpopulations and secreted significant amounts of interferon γ. Conclusions TEV has surface amino groups that are available for chemical coupling. TEV induces both humoral and cellular responses when administered alone intraperitoneally to mice. Therefore, TEV should be evaluated as a vaccine adjuvant when chemically coupled to antigens of choice. PMID:22452850

  15. Triglycerides, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol in rats exposed to premium motor spirit fumes

    PubMed Central

    Aberare, Ogbevire L.; Okuonghae, Patrick; Mukoro, Nathaniel; Dirisu, John O.; Osazuwa, Favour; Odigie, Elvis; Omoregie, Richard

    2011-01-01

    Background: Deliberate and regular exposure to premium motor spirit fumes is common and could be a risk factor for liver disease in those who are occupationally exposed. A possible association between premium motor spirit fumes and plasma levels of triglyceride, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol using a rodent model could provide new insights in the pathology of diseases where cellular dysfunction is an established risk factor. Aim: The aim of this study was to evaluate the possible effect of premium motor spirit fumes on lipids and lipoproteins in workers occupationally exposed to premium motor spirit fumes using rodent model. Materials and Methods: Twenty-five Wister albino rats (of both sexes) were used for this study between the 4th of August and 7th of September, 2010. The rats were divided into five groups of five rats each. Group 1 rats were not exposed to premium motor spirit fumes (control group), group 2 rats were exposed for 1 hour daily, group 3 for 3 hours daily, group 4 for 5 hours daily and group 5 for 7 hours daily. The experiment lasted for a period of 4 weeks. Blood samples obtained from all the groups after 4 weeks of exposure were used for the estimation of plasma levels of triglyceride, total cholesterol, high density lipoprotein- cholesterol and low density lipoprotein- cholesterol. Result: Results showed significant increase in means of plasma total cholesterol and low density lipoprotein levels (P<0.05). The mean triglyceride and total body weight were significantly lower (P<0.05) in the exposed group when compared with the unexposed. The plasma level of high density lipoprotein, the ratio of low density lipoprotein to high density lipoprotein and the ratio of total cholesterol to high density lipoprotein did not differ significantly in exposed subjects when compared with the control group. Conclusion: These results showed that frequent exposure to petrol fumes may be highly

  16. Changes in biological and virulent characteristics of Helicobacter pylori exposed to high salt.

    PubMed

    Xu, Ying; Jing, Jing-Jing; Gong, Yue-Hua; Xu, Qian; Zhang, Wen-Lu; Piao, Ying; Wang, Yan-Li; Yuan, Yuan

    2011-01-01

    The effect of high salt environments on biological characteristics of Helicobacter pylori is still unclear. In the present study, we therefore investigated biological characteristics of the bacterium exposed to high salt concentrations. H. pylori strain, L301, was cultured in media supplemented with different concentrations (3%, 15% and 30%) of sodium chloride (NaCl) under microaerophilic conditions for 48 h. Morphology was assessed by light microscopy, the ATP content was quantitated by single-tube fluorescent light-emission and the levels of CagA and UreB proteins were determined by Western blotting. After exposure to NaCl, H. pylori transformed from common spiral shape to U or even coccoid shapes. The ATP content was significantly higher in 30% NaCl group than in 15% and 3% NaCl group and the level of CagA protein increased with the salt concentration. The urease reaction was all strongly positive in H. pylori exposed to different salt concentrations. The level of 8-OHdG expression was significantly increased in GES-1 cells co-cultured with H. pylori exposed to high salt, compared with the level in uninfected cells. H. pylori survives under exposure to high salt concentrations up to 30%, exhibiting changes in mobility, morphology and CagA expression, associated with increased 8-OHdG in the gastric epithelial cells, indicative of DNA damage.

  17. Urinary arsenic speciation profile in ethnic group of the Atacama desert (Chile) exposed to variable arsenic levels in drinking water.

    PubMed

    Yáñez, Jorge; Mansilla, Héctor D; Santander, I Paola; Fierro, Vladimir; Cornejo, Lorena; Barnes, Ramón M; Amarasiriwardena, Dulasiri

    2015-01-01

    Ethnic groups from the Atacama Desert (known as Atacameños) have been exposed to natural arsenic pollution for over 5000 years. This work presents an integral study that characterizes arsenic species in water used for human consumption. It also describes the metabolism and arsenic elimination through urine in a chronically exposed population in northern Chile. In this region, water contained total arsenic concentrations up to 1250 μg L(-1), which was almost exclusively As(V). It is also important that this water was ingested directly from natural water sources without any treatment. The ingested arsenic was extensively methylated. In urine 93% of the arsenic was found as methylated arsenic species, such as monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. The original ingested inorganic species [As(V)], represent less than 1% of the total urinary arsenic. Methylation activity among individuals can be assessed by measuring primary [inorganic As/methylated As] and secondary methylation [MMA/DMA] indexes. Both methylation indexes were 0.06, indicating a high biological converting capability of As(V) into MMA and then MMA into DMA, compared with the control population and other arsenic exposed populations previously reported.

  18. Natural killer cells in highly exposed hepatitis C-seronegative injecting drug users.

    PubMed

    Mina, M M; Cameron, B; Luciani, F; Vollmer-Conna, U; Lloyd, A R

    2016-06-01

    Injecting drug use remains the major risk factor for hepatitis C (HCV) transmission. A minority of long-term injecting drug users remain seronegative and aviraemic, despite prolonged exposure to HCV - termed highly exposed seronegative subjects. Natural killer (NK) cells have been implicated in this apparent protection. A longitudinal nested, three group case-control series of subjects was selected from a prospective cohort of seronegative injecting drug users who became incident cases (n = 11), remained seronegative (n = 11) or reported transient high-risk behaviour and remained uninfected (n = 11). The groups were matched by age, sex and initial risk behaviour characteristics. Stored peripheral blood mononuclear cells were assayed in multicolour flow cytometry to enumerate natural killer cell subpopulations and to assess functional activity using Toll-like receptor ligands before measurement of activation, cytokine production and natural cytotoxicity receptor expression. Principal components were derived to describe the detailed phenotypic characteristics of the major NK subpopulations (based on CD56 and CD16 co-expression), before logistic regression analysis to identify associations with exposed, seronegative individuals. The CD56(dim) CD16(+) (P = 0.05, OR 6.92) and CD56(dim) CD16(-) (P = 0.05, OR 6.07) principal components differed between exposed, seronegative individuals and pre-infection samples of the other two groups. These included CD56(dim) CD16(+) and CD56(dim) CD16(-) subsets with CD56(dim) CD16(+) IFN-γ and TNF-α on unstimulated cells, and CD56(dim) CD16(-) CD69(+) , CD107a(+) , IFN-γ and TNF-α following TLR stimulation. The cytotoxic CD56(dim) NK subset thus distinguished highly exposed, seronegative subjects, suggesting NK cytotoxicity may contribute to protection from HCV acquisition. Further investigation of the determinants of this association and prospective assessment of protection against HCV infection are warranted.

  19. Co3O4 nanocages with highly exposed {110} facets for high-performance lithium storage

    PubMed Central

    Liu, Dequan; Wang, Xi; Wang, Xuebin; Tian, Wei; Bando, Yoshio; Golberg, Dmitri

    2013-01-01

    Functional materials with both exposed highly reactive planes and hollow structures have attracted considerable attentions with respect to improved catalytic activity and enhanced electrochemical energy storage. Herein, we report the synthesis of unusual single-crystal Co3O4 nanocages with highly exposed {110} reactive facets via a one-step solution method. When tested as anode materials in lithium-ion batteries, these Co3O4 nanocages deliver a high reversible lithium storage capacity of 864 mAh g−1 at 0.2C over 50 cycles and exhibit an excellent rate capability. The dominantly exposed {110} planes, a high density of atomic steps in nanocages, and the large void interiors lead to the regarded superior electrochemical performance. PMID:23995848

  20. High dietary protein combats the stress of Labeo rohita fingerlings exposed to heat shock.

    PubMed

    Kumar, Shivendra; Sahu, N P; Pal, A K; Subramanian, Saravanan; Priyadarshi, Himanshu; Kumar, Vikas

    2011-12-01

    The amelioration effect of high dietary protein against stress was evaluated in Labeo rohita fingerlings, exposed to heat shock. Two hundred and forty fingerlings (6.57 ± 0.04 g, average weight ± SE) were randomly distributed into 4 treatment groups, each with 4 replicates was fed with either of four diets containing different levels of protein (20, 30, 40 or 45%). Water temperatures of all the treatments were within the range of 25.5-26.5°C throughout the experimental period of 30 days. After 30 days of feeding, fish were given heat shock by exposing to 38°C for 2 h. Heat shock significantly decreased (P < 0.05) liver glycogen content in treatment groups fed with 20 and 30% dietary protein, whereas unaffected in the 40 and 45% protein-fed groups. Heat shock significantly increased (P < 0.05) serum glucose and cortisol level in all the treatments. The 40 and 45% dietary protein-fed groups registered significantly higher survival (%) after the heat shock compared with their lower-protein counterparts. Heat shock increased the glycolytic, gluconeogenic, protein metabolic and antioxidative enzymes to cope up with thermal stress. Our results indicate that high-protein diet (≥40%) combats the stress due to heat shock in Labeo rohita.

  1. High-frequency Audiometry Hearing on Monitoring of Individuals Exposed to Occupational Noise: A Systematic Review

    PubMed Central

    Antonioli, Cleonice Aparecida Silva; Momensohn-Santos, Teresa Maria; Benaglia, Tatiana Aparecida Silva

    2015-01-01

    Introduction  The literature reports on high-frequency audiometry as one of the exams used on hearing monitoring of individuals exposed to high sound pressure in their work environment, due to the method́s greater sensitivity in early identification of hearing loss caused by noise. The frequencies that compose the exam are generally between 9 KHz and 20KHz, depending on the equipment. Objective  This study aims to perform a retrospective and secondary systematic revision of publications on high-frequency audiometry on hearing monitoring of individuals exposed to occupational noise. Data Synthesis  This systematic revision followed the methodology proposed in the Cochrane Handbook, focusing on the question: “Is High-frequency Audiometry more sensitive than Conventional Audiometry in the screening of early hearing loss individuals exposed to occupational noise?” The search was based on PubMed data, Base, Web of Science (Capes), Biblioteca Virtual em Saúde (BVS), and in the references cited in identified and selected articles. The search resulted in 6059 articles in total. Of these, only six studies were compatible with the criteria proposed in this study. Conclusion  The performed meta-analysis does not definitively answer the study's proposed question. It indicates that the 16 KHz high frequency audiometry (HFA) frequency is sensitive in early identification of hearing loss in the control group (medium difference (MD = 8.33)), as well as the 4 KHz frequency (CA), this one being a little less expressive (MD = 5.72). Thus, others studies are necessary to confirm the HFA importance for the early screening of hearing loss on individuals exposed to noise at the workplace. PMID:27413413

  2. Myocardial protection induced by fentanyl in pigs exposed to high-dose adrenaline.

    PubMed

    da Luz, Vinicius Fernando; Otsuki, Denise Aya; Gonzalez, Maria Margarita Castro; Negri, Elnara Marcia; Caldini, Elia Garcia; Damaceno-Rodrigues, Nilsa Regina; Malbouisson, Luiz Marcelo Sá; Viana, Bruno Gonçalves; Vane, Matheus Fachini; Carmona, Maria Jose Carvalho

    2015-10-01

    The use of high doses of adrenaline is common in critical patients, especially during cardiac arrest. During these situations, myocardial dysfunction can be a result of multiple factors, including adrenaline use. In addition, opioids have been shown to have anti-arrhythmic and anti-ischemic mechanisms that may confer cardiac protection. This study aimed to evaluate the effects of fentanyl on myocardial function in pigs exposed to high-dose adrenaline. After institutional ethics committee approval, 26 pigs were randomly allocated to receive either 20 μg/kg fentanyl (n = 10; fentanyl group) administered 5 min before five doses of adrenaline (20 μg/kg), equivalent-volume saline (n = 10; saline group) using the same adrenaline dosing protocol, or neither fentanyl nor adrenaline (n = 6; sham group). The fentanyl group showed lower levels of troponin at the end of the sixth hour compared with the saline group (1.91 ± 1.47 vs 5.44 ± 5.35 ng/mL, P = 0.019). Transmission electron microscopy and immunohistochemistry also showed less myocardial injury in the fentanyl group. The conclusion was reached that fentanyl attenuates myocardial injury caused by high-dose adrenaline without blunting the hemodynamic effect of adrenaline.

  3. Analysis of dental hard tissues exposed to high temperatures for forensic applications: An in vitro study

    PubMed Central

    Shekhawat, Kuldeep Singh; Chauhan, Arunima

    2016-01-01

    Aim: The aim of this study was to observe and record the macroscopic, radiographic, and microscopic findings obtained after subjecting the teeth to high temperatures. Materials and Methods: An in vitro study was conducted to observe macroscopic, radiographic, and microscopic changes in dental hard tissues in 60 unrestored non carious extracted human teeth. The teeth were grouped based on age: Below 30 years, 30–40 years, and above 40 years The teeth from each age group were further divided into five subgroups, and each subgroup was subjected to a particular temperature: 200°C, 400°C, 600°C, 800°C, and 1000°C. [C = Celsius]. Results: Various degrees of changes in relation to temperature were observed macroscopically, radiographically, and microscopically. The histological examination was limited for teeth exposed to 200°C. Conclusion: This investigation was carried out to study the gross changes, radiographic changes and histological changes in dental hard tissues exposed to high temperatures, which is an important part of forensic science. The aforementioned alterations caused by heat may provide useful information about temperature ranges and duration of exposure to high temperatures. PMID:27555725

  4. Quaternary ammonium groups exposed at the surface of silica nanoparticles suitable for DNA complexation in the presence of cationic lipids.

    PubMed

    Reinhardt, Nora; Adumeau, Laurent; Lambert, Olivier; Ravaine, Serge; Mornet, Stéphane

    2015-05-28

    The production of silica nanoparticles (NPs) exposing quaternary ammonium groups (NPQ(+)) has been achieved using an optimized chemical surface functionalization protocol. The procedures of surface modification and quaternization of amino groups were validated by diffuse reflectance infrared Fourier transform (DRIFT) and (1)H NMR spectroscopies. Compared to nonquaternized aminated NP, the colloidal stability of NPQ(+) was improved for various pH and salt conditions as assessed by ζ potential and light scattering measurements. In the context of their use for nucleic acid delivery, DNA efficiently bound to NPQ(+) analyzed by cosedimentation assays for a large pH range and various NaCl concentrations and exhibited a better efficacy at basic pH than nonquaternized NP. The study of NPQ(+)/DNA/cationic lipids ternary complexes was carried out with 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) and analyzed by cryo-electron microscopy (cryo-EM). Cryo-EM images showed ternary assemblies where condensed DNA strands are sandwiched between the NPQ(+) surface and the cationic lipid bilayer. Because of an unusual electrostatic colloidal stability of NPQ(+) and a high propensity to bind DNA molecules particularly at high salt concentrations, a novel type of ternary assembly has been formed that might impact the delivery properties of these complexes including their stability in biological environment.

  5. Quaternary ammonium groups exposed at the surface of silica nanoparticles suitable for DNA complexation in the presence of cationic lipids.

    PubMed

    Reinhardt, Nora; Adumeau, Laurent; Lambert, Olivier; Ravaine, Serge; Mornet, Stéphane

    2015-05-28

    The production of silica nanoparticles (NPs) exposing quaternary ammonium groups (NPQ(+)) has been achieved using an optimized chemical surface functionalization protocol. The procedures of surface modification and quaternization of amino groups were validated by diffuse reflectance infrared Fourier transform (DRIFT) and (1)H NMR spectroscopies. Compared to nonquaternized aminated NP, the colloidal stability of NPQ(+) was improved for various pH and salt conditions as assessed by ζ potential and light scattering measurements. In the context of their use for nucleic acid delivery, DNA efficiently bound to NPQ(+) analyzed by cosedimentation assays for a large pH range and various NaCl concentrations and exhibited a better efficacy at basic pH than nonquaternized NP. The study of NPQ(+)/DNA/cationic lipids ternary complexes was carried out with 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) and analyzed by cryo-electron microscopy (cryo-EM). Cryo-EM images showed ternary assemblies where condensed DNA strands are sandwiched between the NPQ(+) surface and the cationic lipid bilayer. Because of an unusual electrostatic colloidal stability of NPQ(+) and a high propensity to bind DNA molecules particularly at high salt concentrations, a novel type of ternary assembly has been formed that might impact the delivery properties of these complexes including their stability in biological environment. PMID:25950202

  6. High fat diet exacerbates vascular endothelial dysfunction in rats exposed to continuous hypobaric hypoxia.

    PubMed

    Zhao, Yan-Xia; Tang, Feng; Ga, Qin; Wuren, Tana; Wang, Ya-Ping; Rondina, Matthew T; Ge, Ri-Li

    2015-02-13

    Independently, a high fat diet and hypoxia are associated with vascular endothelial dysfunction (VED) and often occur concurrently in patients. Nevertheless, the effects of a high fat diet on vascular endothelial function combined with hypoxia, a situation occurring with increasing frequency in many parts of the world, remain largely unknown. We investigated the effects of a high fat diet on vascular endothelial function in rats exposed to continuous hypoxia for 4 weeks. Seventy two male Sprague-Dawley rats were randomly divided into 3 groups: a hypoxia group fed regular chow, a combined hypoxia and high fat diet (HFD) group, and for comparison, rats maintained in normoxia, regular chow conditions were set as baseline (BL) group. The experimental data of BL group were obtained at beginning of hypoxia given in the other groups. Continuous hypoxia was induced in a hypobaric chamber maintained at an altitude of 5000 m. Compared to hypoxic conditions alone, hypoxia plus a HFD prevented adaptive changes in plasma nitric oxide (NOx) levels and caused earlier and more severe changes in aortic endothelial structures. Functionally, hypoxia plus a HFD resulted in impaired endothelium-dependent vasorelaxation responses to acetylcholine and altered the bioavailability of the nitric oxide synthase (NOS) substrate L-Arginine. At the molecular level, hypoxia plus a HFD blunted increases in endothelial NOS (eNOS) mRNA and protein in aortic endothelial tissue. Taken together, our findings demonstrate that in the setting of hypoxia, a high fat diet leads to earlier and more severe VED than hypoxia alone. These data have important implications for populations residing at high-altitude, as dietary patterns shift towards increased fat intake. PMID:25603049

  7. Effectiveness of a School-Based Group Psychotherapy Program for War-Exposed Adolescents: A Randomized Control Trial

    ERIC Educational Resources Information Center

    Layne, Christopher M.; Saltzman, William R.; Poppleton, Landon; Burlingame, Gary M.; Pasalic, Alma; Durakovic, Elvira; Music, Mirjana; Campara, Nihada; Dapo, Nermin; Arslanagic, Berina; Steinberg, Alan M.; Pynoos, Robert S.

    2008-01-01

    The study assesses the comparative efficacy of a classroom-based psycho-education and skills intervention and a school-based trauma- and grief-focused group treatment of a three-tiered mental health program for adolescents exposed to severe war-trauma, traumatic bereavement, and postwar adversity. The two-tier approach, combined with…

  8. Avoidance Symptom Presentation of Preschoolers Exposed to Intimate Partner Violence in a Group Therapy Setting

    ERIC Educational Resources Information Center

    Galano, Maria M.; Miller, Laura E.; Graham-Bermann, Sandra A.

    2014-01-01

    Post-traumatic stress disorder (PTSD) is a serious problem for children exposed to intimate partner violence (IPV). Recent changes to diagnostic criteria for PTSD include a reduction in avoidance symptom criteria from three to one and the separation of emotional numbing from avoidance symptoms, thus creating a need to better understand how…

  9. Urine metabolomics of women from small villages exposed to high environmental cadmium levels.

    PubMed

    Xu, Yinghua; Wang, Jin; Liang, Xuxia; Gao, Yanhong; Chen, Wencai; Huang, Qiong; Liang, Chunsui; Tang, Liuying; Ouyang, Gangfeng; Yang, Xingfen

    2016-05-01

    The present study aimed to identify urine metabolites in women exposed to high cadmium (Cd) levels. Twenty-one women exposed to environmental Cd and 12 age-matched controls were categorized as high exposure (urine Cd ≥ 15 μg/g creatinine; n = 9) or low exposure (15 μg/g creatinine > urine Cd > 5 μg/g creatinine; n = 12). Low-molecular weight metabolites in urine were analyzed by gas chromatography and mass spectrometry after derivatization. An orthogonal partial least-squares discriminant analysis model was constructed, and metabolites from the dimensional model were selected according to the variable importance in projection (>1). Metabolites differing significantly in abundance between different exposure groups were identified by searching mass spectral databases, and related pathways were analyzed using the Kyoto Encyclopedia of Genes and Genomes. Approximately 110 significantly different metabolites were detected with variable importance in projection > 1, and 48 of them were found to differ markedly in abundance among the 3 groups. Twenty-seven matched with known metabolites, including 22 significantly increased and 5 markedly decreased in the high-exposure group (p < 0.01). Kyoto Encyclopedia of Genes and Genomes results indicated that carbohydrate, amino acid, bone, and intestinal flora metabolism and the tricarboxylic acid cycle were affected by Cd exposure. The present study identified metabolites that differed in abundance in response to Cd exposure. Further studies may connect these biomarkers to early damage caused by Cd.

  10. Germination of vegetable seeds exposed to very high pressure

    NASA Astrophysics Data System (ADS)

    Mori, Y.; Yokota, S.; Ono, F.

    2012-07-01

    Effects of high hydrostatic pressure were investigated on vegetable seeds in the GPa range to examine the potentialities of breed improvement by high-pressure processing. Specimens of several seeds of broccoli (Brassica oleracea var. italica), Turnip leaf (Brassica rapa var. perviridis) and Potherb Mustard (Brassica rapa var. nipposinica) were put in a teflon capsule with liquid high pressure medium, fluorinate, and inserted into a pyrophillite cube. By using a cubic anvil press a hydrostatic pressure of 5.5 GP a was applied to these seeds for 15 minutes. After being brought back to ambient pressure, they were seeded on humid soil in a plant pot. Many of these vegetable seeds began to germinate within 6 days after seeded.

  11. Warts and All: Exposing History to High School Students.

    ERIC Educational Resources Information Center

    Stanley, Gregory

    2003-01-01

    A high school history teacher explains how he tries to make history interesting for his students by suggesting that American history is full of great stories. Talks specifically about teaching about Thomas Jefferson and his relationship with Sally Hemings. Presents a rationale for addressing controversial issues in history instruction. (JOW)

  12. Nanostructures and pinholes on W surfaces exposed to high flux D plasma at high temperatures

    NASA Astrophysics Data System (ADS)

    Jia, Y. Z.; Liu, W.; Xu, B.; Luo, G.-N.; Li, C.; Fu, B. Q.; De Temmerman, G.

    2015-08-01

    Nanostructures and pinholes formed on tungsten surface exposed to high fluxes (1024 m-2 s-1) deuterium ions at 943 K and 1073 K were studied by scanning electron microscopy and electron backscatter diffraction. Nanostructure formation is observed at 943 K and 1073 K, and exhibits a strong dependence on the surface orientation. With increasing fluence, pinholes appear on the surface and are mainly observed on grains with surface normal near [1 1 1]. The pinholes are speculated to be caused by the rupture of bubbles formed near the surface. The formation of pinholes has no obvious relationship with the surface nanostructures.

  13. Copper uptake by Eichhornia crassipes exposed at high level concentrations.

    PubMed

    Melignani, Eliana; de Cabo, Laura Isabel; Faggi, Ana María

    2015-06-01

    The objective of this study was to assess the growth of water hyacinth (Eichhornia crassipes) and its ability to accumulate Cu from polluted water with high Cu concentrations and a mixture of other contaminants under short-term exposure, in order to use this species for the remediation of highly contaminated sites. Two hydroponic experiments were performed under greenhouse conditions for 7 days. One of them consisted of growing water hyacinth in Hoagland solution supplemented with 15 or 25 mg Cu/L and a control. The other one contained water hyacinth growing in polluted river water supplemented with 15 mg Cu/L and a control. Cu was accumulated principally in roots. The maximum Cu concentration was 23,387.2 mg/kg dw in the treatment of 25 mg Cu/L in Hoagland solution. Cu translocation from roots to leaves was low. The mixture of 15 mg Cu/L with polluted water did not appear to have toxic effects on the water hyacinth. This plant showed a remarkable uptake capacity under elevated Cu concentrations in a mixture of pollutants similar to pure industrial effluents in a short time of exposure. This result has not been reported before, to our knowledge. This species is suitable for phytoremediation of waters subject to discharge of mixed industrial effluents containing elevated Cu concentrations (≥15 mg Cu/L), as well as nutrient-rich domestic wastewaters.

  14. Copper uptake by Eichhornia crassipes exposed at high level concentrations.

    PubMed

    Melignani, Eliana; de Cabo, Laura Isabel; Faggi, Ana María

    2015-06-01

    The objective of this study was to assess the growth of water hyacinth (Eichhornia crassipes) and its ability to accumulate Cu from polluted water with high Cu concentrations and a mixture of other contaminants under short-term exposure, in order to use this species for the remediation of highly contaminated sites. Two hydroponic experiments were performed under greenhouse conditions for 7 days. One of them consisted of growing water hyacinth in Hoagland solution supplemented with 15 or 25 mg Cu/L and a control. The other one contained water hyacinth growing in polluted river water supplemented with 15 mg Cu/L and a control. Cu was accumulated principally in roots. The maximum Cu concentration was 23,387.2 mg/kg dw in the treatment of 25 mg Cu/L in Hoagland solution. Cu translocation from roots to leaves was low. The mixture of 15 mg Cu/L with polluted water did not appear to have toxic effects on the water hyacinth. This plant showed a remarkable uptake capacity under elevated Cu concentrations in a mixture of pollutants similar to pure industrial effluents in a short time of exposure. This result has not been reported before, to our knowledge. This species is suitable for phytoremediation of waters subject to discharge of mixed industrial effluents containing elevated Cu concentrations (≥15 mg Cu/L), as well as nutrient-rich domestic wastewaters. PMID:25529492

  15. High prevalence of co-factor independent anticardiolipin antibodies in malaria exposed individuals

    PubMed Central

    Consigny, P H; Cauquelin, B; Agnamey, P; Comby, E; Brasseur, P; Ballet, J J; Roussilhon, C

    2002-01-01

    Anticardiolipin antibodies (aCL) were investigated in 137 individuals chronically exposed to malaria and living in Africa and Asia. They belonged to several groups according to parasite (Plasmodium falciparum or vivax) and clinical manifestations (i.e. asymptomatic parasite carriers, acute uncomplicated attack or severe malaria episodes). aCL were measured in an enzyme immunoassay (ELISA) performed in the presence of either goat serum (aCLs) or gelatin (aCLg). In a group of 53 patients with autoimmune manifestations (i.e. antiphospholipid syndrome and/or lupus), detection of IgG but not IgM aCL was markedly reduced in the presence of gelatin. In malaria donors, high prevalence of serum co-factor-independent IgG and IgM were detected, and the presence of goat serum in the assay consistently decreased their detection. aCLg levels were found to be related to the clinical/endemic status of donors. IgG aCLg were found to be higher in asymptomatic P. falciparum carriers than in patients with uncomplicated acute or cerebral malaria. IgM aCLg were higher in the cerebral malaria group than in groups with uncomplicated acute malaria patients or asymptomatic individuals. Data suggest that using a serum co-factor independent, sensitive ELISA, aCL are commonly detected during malarial infections and related to malarial infection status. PMID:11882047

  16. Plasma gonadotrophins, prolactin and corticosterone concentrations in male mice exposed to high altitude.

    PubMed

    Rattner, B A; Macmillan, B T; Michael, S D; Altland, P D

    1980-11-01

    Groups of sexually-naive male NFR/N mice were maintained at sea level or exposed to simulated altitudes of 18 000 ft (5486 m) or 22 000 ft (6705 m) for 1, 3, 7, 14 or 28 days. Plasma LH concentrations were slightly but not significantly depressed after 1 day of hypoxia. Plasma FSH values were reduced (P < 0.05) after 1, 7, 14 and 28 days of exposure to 22 000 ft when compared to the values in the other groups. Prolactin concentrations fluctuated considerably, but were not uniformly affected by high altitude exposure. Exposure to 18 000 ft resulted in an elevation of plasma corticosterone concentration (P < 0.05) for 3 days, which was followed by a decline to control group values, whereas at 22 000 ft corticosterone levels remained elevated. These findings indicate that plasma LH values are transiently reduced during the initial 24 h of exposure to high altitude and that plasma FSH concentrations are depressed in a sustained manner during severe hypoxia.

  17. Using Creative Group Techniques in High Schools

    ERIC Educational Resources Information Center

    Veach, Laura J.; Gladding, Samuel T.

    2007-01-01

    Groups in high schools that use creative techniques help adolescents express their emotions appropriately, behave differently, and gain insight into themselves and others. This article looks at seven different creative arts media--music, movement, visual art, literature, drama, play, and humor--and offers examples of how they can be used in groups…

  18. Non-auditory health effects among air force crew chiefs exposed to high level sound.

    PubMed

    Jensen, Anker; Lund, Søren Peter; Lücke, Thorsten Høgh; Clausen, Ole Voldum; Svendsen, Jørgen Torp

    2009-01-01

    The possibility of non-auditory health effects in connection with occupational exposure to high level sound is supposed by some researchers, but is still debated. Crew chiefs on airfields are exposed to high-level aircraft sound when working close to aircraft with running engines. We compared their health status with a similar control group who were not subject to this specific sound exposure. Health records of 42 crew chiefs were compared to health records of 42 aircraft mechanics and 17 former crew chiefs. The specific sound exposure of crew chiefs was assessed. The number of reported disease cases was generally small, but generally slightly higher among mechanics than among crew chiefs. Diseases of the ear were more frequent among crew chiefs (not significant). Former crew chiefs reported fewer diseases of the ear and more airways infections (both significant). The sound exposure during launch was up to 144 dB (peak) and 124 dB (L(eq) ), but for limited time. The study did not reveal a higher disease frequency in general among crew chiefs. However, it did reveal a tendency to ear diseases, possibly due to their exposure to high-level sound.

  19. Differential therapeutic outcomes of community-based group interventions for women and children exposed to intimate partner violence.

    PubMed

    McWhirter, Paula T

    2011-08-01

    Two community-based group therapies, emotion focused versus goal oriented, are compared among women exposed to intimate partner violence (n = 46) and their children ( n = 48) aged between 6 and 12 years. A series of repeated measures analyses are employed to evaluate the effects of time from baseline to postintervention following random assignment. Main and treatment effects for women provide support for the relative effectiveness in increasing quality of social support in the emotion-focused intervention and in the reduction of both family conflict and alcohol use for the goal-oriented intervention. PMID:20889533

  20. High risk groups in oil shale workforce

    SciTech Connect

    Gratt, L.B.; Perry, B.W.; Marine, W.M.; Savitz, D.A.

    1984-04-01

    The workforce risks of a hypothetical one million barrels-per-day oil shale industry were estimated. The risks for the different workforce segments were compared and high risk groups were identified. Accidents and injuries were statistically described by rates for fatalities, for accidents with days lost from work, and for accidents with no days lost from work. Workforce diseases analyzed were cancers, silicosia, pneumoconiosis, chronic bronchitis, chronic airway obstruction, and high frequency hearing loss. A comparison of the workforce groups under different risk measures (occurrence, fatality, and life-loss expectancy) was performed. The miners represented the group with the largest fatality and the most serious accident rate, although the estimated rates were below the average industry-wide underground mining experience. Lung disease from inhalation exposure of about the nuisance dust threshold limit value presents a significant risk for future concerns. If future environmental dust exposure is at the 100 ..mu..g/m/sup 3/ alpha-quartz level, safety improvements in the mining sector are of prime importance to reduce the oil shale worker's life-loss expectancy. 11 references, 1 figure, 11 tables.

  1. Levels of 8-hydroxy-2'-deoxyguanosine in DNA of white blood cells from workers highly exposed to asbestos in Germany.

    PubMed

    Marczynski, B; Rozynek, P; Kraus, T; Schlösser, S; Raithel, H J; Baur, X

    2000-07-10

    Asbestos fibers have genotoxic effects and are a potential carcinogenic hazard to occupationally exposed workers. The ability of inhaled asbestos fibers to induce the formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the DNA of white blood cells (WBC) of workers highly exposed at the workplace has been studied. The 8-OHdG adduct level of asbestos-exposed workers was significantly increased (p<0.001) compared to that in the control group in all three years of the study. Asbestos-exposed individuals showed a mean value of 2.61+/-0.91 8-OHdG/10(5) dG (median 2.49, n=496) in 1994-1995, 2.96+/-1.10 8-OHdG/10(5) dG (median 2.76, n=437) in 1995-1996 and 2.55+/-0.56 8-OHdG/10(5) dG (median 2.53, n=447) in 1996-1997. For the control subjects, a mean of 1.52+/-0.39 (median 1.51, n=214) was determined. The results indicate that human DNA samples from exposed individuals contain between 1.7 times and twice the level of oxidative damage relative to that found in control samples in all 3 years of the study. The studies presented here show that asbestos exposure can result in oxidative DNA damage. Our data confirm that oxidative DNA damage occurs in the WBC of workers highly exposed to asbestos fibers, thus supporting the hypothesis that asbestos fibers damage cells through an oxidative mechanism. These in vivo findings underline the importance of oxidative damage in asbestos-induced carcinogenesis and highlight the need for exploring the molecular basis of asbestos-induced diseases, and for more effective diagnosis, prevention and therapy of mesothelioma, lung cancer and pulmonary fibrosis. In addition, preventive and therapeutic approaches using antioxidants may be relevant.

  2. Effect of surface-exposed chemical groups on calcium-phosphate mineralization in water-treatment systems.

    PubMed

    Steiner, Zvi; Rapaport, Hanna; Oren, Yoram; Kasher, Roni

    2010-10-15

    Calcium-phosphate-scale formation on reverse osmosis (RO) membranes is a major limiting factor for cost-effective desalination of wastewater. We determined the effects of various organic chemical groups found on membrane surfaces on calcium-phosphate scaling. Langmuir films exposing different functional groups were equilibrated with a solution simulating the ionic profile of secondary effluent (SSE). Surface pressure-area (Langmuir) isotherms combined with ICP elemental analyses of the interfacial precipitate suggested acceleration of calcium-phosphate mineralization by the surface functional groups in the order: PO(4) > COOH ∼ NH(2) > COOH:NH(2) (1:1) > OH > ethylene glycol. Immersion of gold-coated silicon wafers self-assembled with different alkanethiols in SSE solution showed formation of a hydroxyapatite precipitate by X-ray diffraction and ATR-IR analysis. Data showed diverse influences of functional groups on mineralization, implying low calcium-phosphate scaling for uncharged surfaces or surfaces coated with both positively and negatively charged groups. This information is valuable for understanding scaling processes, and for designing of novel low-scaling membranes for water desalination.

  3. Time may not fully attenuate solvent-associated cognitive deficits in highly exposed workers

    PubMed Central

    Gutierrez, Laure-Anne; Okechukwu, Cassandra A.; Singh-Manoux, Archana; Amieva, Hélène; Goldberg, Marcel; Zins, Marie; Berr, Claudine

    2014-01-01

    Objective: To test the effects of lifetime occupational solvent exposure, as measured by dose and timing, on performance on multiple cognitive tests among retired French utility workers. Methods: A total of 2,143 retirees in the GAZEL cohort underwent cognitive testing in 2010. Lifetime exposure to chlorinated solvents, petroleum solvents, and benzene was assessed using a job exposure matrix. We modeled effects of lifetime solvent dose, timing of last exposure, and a combination of these metrics on risk for cognitive impairment. Results: Thirty-three percent of participants were exposed to chlorinated solvents, 26% to benzene, and 25% to petroleum solvents. High exposure to solvents was significantly associated with poor cognition; for example, those highly exposed to chlorinated solvents were at risk of impairment on the Mini-Mental State Examination (risk ratio 1.18; 95% confidence interval 1.06, 1.31), the Digit Symbol Substitution Test (1.54; 1.31, 1.82), semantic fluency test (1.33; 1.14, 1.55), and the Trail Making Test B (1.49; 1.25, 1.77). Retirees at greatest risk for deficits had both high lifetime exposure to solvents and were last exposed 12 to 30 years before testing. Risk was somewhat elevated among those with high lifetime exposure who were last exposed 31 to 50 years before testing. Those with high, recent exposure exhibited impairment in almost all domains, including those not typically associated with solvent exposure. Conclusions: While risk of cognitive impairment among moderately exposed workers may attenuate with time, this may not be fully true for those with higher exposure. This has implications for physicians working with formerly solvent-exposed patients as well as for workplace exposure limit policies. PMID:24821933

  4. Reduced anticipatory dopamine responses to food in rats exposed to high fat during early development.

    PubMed

    Naef, L; Moquin, L; Gratton, A; Walker, C-D

    2013-06-01

    We have previously demonstrated that exposure to high fat (HF) during early development alters the presynaptic regulation of mesolimbic dopamine (DA), and increases incentive motivation for HF food rewards. The goal of the present experiments was to examine the long-term consequences of early exposure to HF on anticipatory and consumatory nucleus accumbens (NAc) DA responses to HF food rewards. Mothers were maintained on a HF (30% fat) or control diet (CD; 5% fat) from gestation day 13 to postnatal day 22 when offspring from both diet groups were weaned and maintained on the CD until adulthood. In vivo NAc DA responses to food anticipation and consumption were measured in a Pavlovian conditioning paradigm using voltammetry in freely moving rats. HF-exposed offspring displayed reduced NAc DA responses to a tone previously paired with the delivery of HF food rewards. In an unconditioned protocol, consumatory NAc DA responses could be isolated, and were similar in HF and control offspring. These data demonstrate that exposure to HF through maternal diet during early development might program behavioral and functional responses associated with mesolimbic DA neurotransmission, thus leading to an increased HF feeding and obesity.

  5. Assessment of DNA damage in car spray painters exposed to organic solvents by the high-throughput comet assay.

    PubMed

    Londoño-Velasco, Elizabeth; Martínez-Perafán, Fabián; Carvajal-Varona, Silvio; García-Vallejo, Felipe; Hoyos-Giraldo, Luz Stella

    2016-05-01

    Occupational exposure as a painter is associated with DNA damage and development of cancer. Comet assay has been widely adopted as a sensitive and quantitative tool for DNA damage assessment at the individual cell level in populations exposed to genotoxics. The aim of this study was to assess the application of the high-throughput comet assay, to determine the DNA damage in car spray painters. The study population included 52 car spray painters and 52 unexposed subjects. A significant increase in the %TDNA median (p <  0.001) was observed in the exposed group in comparison to the unexposed group. Neither age (%TDNA: p =  0.913) nor time of exposure (%TDNA: p = 0.398) were significantly correlated with DNA damage. The car spray painters who consumed alcohol did not show a significant increase in DNA damage compared to nonalcohol consumers (p  > 0.05). The results showed an increase in DNA breaks in car spray painters exposed to organic solvents and paints; furthermore, they demonstrated the application of high-throughput comet assay in an occupational exposure study to genotoxic agents. PMID:26998723

  6. Assessment of DNA damage in car spray painters exposed to organic solvents by the high-throughput comet assay.

    PubMed

    Londoño-Velasco, Elizabeth; Martínez-Perafán, Fabián; Carvajal-Varona, Silvio; García-Vallejo, Felipe; Hoyos-Giraldo, Luz Stella

    2016-05-01

    Occupational exposure as a painter is associated with DNA damage and development of cancer. Comet assay has been widely adopted as a sensitive and quantitative tool for DNA damage assessment at the individual cell level in populations exposed to genotoxics. The aim of this study was to assess the application of the high-throughput comet assay, to determine the DNA damage in car spray painters. The study population included 52 car spray painters and 52 unexposed subjects. A significant increase in the %TDNA median (p <  0.001) was observed in the exposed group in comparison to the unexposed group. Neither age (%TDNA: p =  0.913) nor time of exposure (%TDNA: p = 0.398) were significantly correlated with DNA damage. The car spray painters who consumed alcohol did not show a significant increase in DNA damage compared to nonalcohol consumers (p  > 0.05). The results showed an increase in DNA breaks in car spray painters exposed to organic solvents and paints; furthermore, they demonstrated the application of high-throughput comet assay in an occupational exposure study to genotoxic agents.

  7. Calcium-dependent binding of rabbit C-reactive protein to supported lipid monolayers containing exposed phosphorylcholine group.

    PubMed Central

    Sui, S F; Sun, Y T; Mi, L Z

    1999-01-01

    The interaction of rabbit C-reactive protein (rCRP) with a supported monolayer containing a phosphorylcholine moiety was studied. Three types of phospholipids were synthesized, each containing a insertion spacer of eight, six, or three atoms between the phosphorylcholine group and hydrophobic tail. By varying the length of the insertion spacer, we can vary the extension of the phosphorylcholine group from the membrane surface. By varying the monolayer composition, we can control the lateral distance between the exposed phosphorylcholine groups. Using the surface plasmon resonance technique (SPR), we demonstrated that the calcium-dependent binding of rCRP to the model membrane is governed not only by the ability of the ligand to access the binding pocket fully (spacer length), but also by lateral hindrance within the two-dimensional plane of the membrane. The value of the apparent binding constant was estimated by theoretical analysis, which is obviously dependent on the composition of the lipid mixture, and a maximum of (9.9 +/- 1.5) x 10(6) M-1 was obtained. PMID:9876145

  8. Impaired Lipid and Glucose Homeostasis in Hexabromocyclododecane-Exposed Mice Fed a High-Fat Diet

    PubMed Central

    Koike, Eiko; Win-Shwe, Tin-Tin; Yamamoto, Megumi; Takano, Hirohisa

    2014-01-01

    Background: Hexabromocyclododecane (HBCD) is an additive flame retardant used in the textile industry and in polystyrene foam manufacturing. Because of its lipophilicity and persistency, HBCD accumulates in adipose tissue and thus has the potential of causing metabolic disorders through disruption of lipid and glucose homeostasis. However, the association between HBCD and obesity remains unclear. Objectives: We investigated whether exposure to HBCD contributes to initiation and progression of obesity and related metabolic dysfunction in mice fed a normal diet (ND) or a high-fat diet (HFD). Methods: Male C57BL/6J mice were fed a HFD (62.2 kcal% fat) or a ND and treated orally with HBCD (0, 1.75, 35, or 700 μg/kg body weight) weekly from 6 to 20 weeks of age. We examined body weight, liver weight, blood biochemistry, histopathological changes, and gene expression profiles in the liver and adipose tissue. Results: In HFD-fed mice, body and liver weight were markedly increased in mice treated with the high (700 μg/kg) and medium (35 μg/kg) doses of HBCD compared with vehicle. This effect was more prominent in the high-dose group. These increases were paralleled by increases in random blood glucose and insulin levels and enhancement of microvesicular steatosis and macrophage accumulation in adipose tissue. HBCD-treated HFD-fed mice also had increased mRNA levels of Pparg (peroxisome proliferator-activated receptor-γ) in the liver and decreased mRNA levels of Glut4 (glucose transporter 4) in adipose tissue compared with vehicle-treated HFD-fed mice. Conclusions: Our findings suggest that HBCD may contribute to enhancement of diet-induced body weight gain and metabolic dysfunction through disruption of lipid and glucose homeostasis, resulting in accelerated progression of obesity. Citation: Yanagisawa R, Koike E, Win-Shwe TT, Yamamoto M, Takano H. 2014. Impaired lipid and glucose homeostasis in hexabromocyclododecane-exposed mice fed a high-fat diet. Environ Health

  9. Photodegradation effects in materials exposed to high flux solar and solar simulated radiation

    SciTech Connect

    Ignatiev, A.

    1992-04-01

    This report contains study results about photodegradation effects in materials exposed to high flux solar and solar simulated radiation. The studies show that high flux photoirradiation of materials can result in significant changes in the stability of materials. Photodesorption and photo-enhanced oxidation were determined to be the major mechanisms. These mechanisms were shown to affect, in extremely adverse ways, the expected thermal stability of solar relevant materials, especially stainless steels, (It is expected that related high temperature alloy steels will be similarly affected.) An analytical expression was generated to predict the flux behavior of the steels using {number_sign}304 as a prototypical stainless steel system.

  10. Gastric dilatation syndrome associated with chronic nephropathy, hypergastrinemia, and gastritis in mice exposed to high levels of environmental antigens.

    PubMed

    García, A; Erdman, S; Sheppard, B J; Murphy, J C; Fox, J G

    2001-06-01

    Gastric dilatation (GD) has been observed in Tac:(SW)fBR surveillance mice, with mean age of 10 months, that are exposed to high levels of environmental antigens during routine exposure to dirty bedding. The aim of the study reported here was to determine whether GD was associated with other systemic conditions affecting mice. Three groups of nine animals including-surveillance mice not exposed to dirty bedding (control), surveillance mice with out GD (NGD), and surveillance mice with GD (group GD)-had mean stomach weight with ingesta of 0.5 +/- 0.02 g, 1.09 +/- 0.07 g (P < 0.0001), and 2.54 +/- 0.4 g (P < 0.0001), respectively. Mean serum creatinine concentration was significantly higher in GD (1.6 +/- 0.25 mg/dl), compared with NGD (0.17 +/- 0.22 mg/dl, P < 0.0001) and control (0.2 +/- 0.16 mg/ dl, P < 0.0001) mice. In addition, lesions consistent with severe chronic nephropathy and mild gastritis were common in GD, compared with NGD and control mice. Finally, serum amidated gastrin concentration was significantly high in GD (179.37 +/- 53.86 pM, P < 0.03) and NGD (264.89 +/- 115.89 pM, P < 0.009), compared with control (60.77 +/- 8.39 pM) mice. Gastric dilatation syndrome is associated with chronic nephropathy, hypergastrinemia, and gastritis in surveillance mice exposed to high levels of environmental antigens. PMID:11924783

  11. CLEFT PALATE IN HIV-EXPOSED NEWBORNS OF MOTHERS ON HIGHLY ACTIVE ANTIRETROVIRAL THERAPY

    PubMed Central

    James, Ayotunde; Oluwatosin, Babatunde; Njideka, Georgina; Babafemi; Benjamin, Onyekwere George; Olufemi, David; Leo, Robert; Folorunso, Isaac; Phylis; Olusina, Olusegun

    2014-01-01

    Aims Cleft lip/palate, though rare, is the commonest head and neck congenital malformation. Both genetic and environmental factors have been implicated in the aetiopathogenesis but the role of in-utero exposure to human immunodeficiency virus (HIV) and highly active antiretroviral therapy (HAART) is still being investigated. This short communication reports the occurrence of cleft palate in three newborns exposed in-utero to HIV and HAART. Material and methods This is a case series of HIV-exposed newborns observed to have cleft palate among a larger cohort of HIV-exposed and unexposed newborns in a study evaluating the effect of HIV infection and HAART on newborn hearing. The Risk Ratio (RR) was calculated to detect a potential association between in-utero exposure to Efavirenz containing ART and cleft palate. Results Three HIV-exposed newborns with cleft palate were identified during hearing screening performed on 126 HIV-exposed and 121 HIV unexposed newborns. Two had exposure to tenofovir+lamivudine+efavirenz (TDF+3TC+EFV) while the third had exposure to zidovudine+lamivudine+nevirapine (ZDV+3TC+NVP) during the first trimester. There was no statistically significant association between presence of cleft palate and exposure to an EFV containing HAART regimen (p=0.07, RR=10.95 [0.94-126.84]). Conclusions This communication highlights the possible aetiologic role of HAART in cleft palate, the need for further prospective follow-up studies and establishment of antiretroviral pregnancy, birth and neonatal registries. PMID:25653715

  12. Animal Rights Groups Target High School Dissection.

    ERIC Educational Resources Information Center

    Trotter, Andrew

    1992-01-01

    Two groups leading the charge against dissection are People for the Ethical Treatment of Animals (PETA) and the Student Action Corps for Animals (SACA). Protests by student and community members remain the movement's strongest weapon. (MLF)

  13. Effectiveness and specificity of a classroom-based group intervention in children and adolescents exposed to war in Lebanon

    PubMed Central

    KARAM, ELIE G.; FAYYAD, JOHN; NASSER KARAM, AIMEE; CORDAHI TABET, CAROLINE; MELHEM, NADINE; MNEIMNEH, ZEINA; DIMASSI, HANI

    2008-01-01

    The purpose of this study was to examine the effectiveness and specificity of a classroom-based psychosocial intervention after war. All students (n=2500) of six villages in Southern Lebanon designated as most heavily exposed to war received a classroom-based intervention delivered by teachers, consisting of cognitive-behavioural and stress inoculation training strategies. A random sample of treated students (n=101) and a matched control group (n=93) were assessed one month post-war and one year later. Mental disorders and psychosocial stressors were assessed using the Diagnostic Interview for Children and Adolescents - Revised with children and parents. War exposure was measured using the War Events Questionnaire. The prevalence of major depressive disorder (MDD), separation anxiety disorder (SAD) and post-traumatic stress disorder (PTSD) was examined pre-war, one month post-war (pre-intervention), and one year post-war. Specificity of treatment was determined by rating teachers’ therapy diaries. The rates of disorders peaked one month post-war and decreased over one year. There was no significant effect of the intervention on the rates of MDD, SAD or PTSD. Post-war MDD, SAD and PTSD were associated with pre-war SAD and PTSD, family violence parameters, financial problems and witnessing war events. These findings have significant policy and public health implications, given current practices of delivering universal interventions immediately post-war. PMID:18560511

  14. Proposed stratigraphic nomenclature and macroscopic identification of lithostratigraphic units of the Paintbrush Group exposed at Yucca Mountain, Nevada

    SciTech Connect

    Buesch, D.C.; Spengler, R.W.; Moyer, T.C.; Geslin, J.K.

    1996-09-01

    This paper describes the formations of the Paintbrush Group exposed at Yucca Mountain, Nevada, presents a detailed stratigraphic nomenclature for the Tiva Canyon and Topopah spring Tuffs, and discusses the criteria that define lithostratigraphic units. The Tiva Canyon and Topopah Spring Tuffs are divided into zones, subzones, and intervals on the basis of macroscopic features observed in surface exposures and borehole samples. Primary divisions reflect depositional and compositional zoning that is expressed by variations in crystal content, phenocryst assemblage, pumice content and composition, and lithic content. Secondary divisions define welding and crystlalization zones, depositional features, or fracture characteristics. Both formations are divided into crystal-rich and crystal-poor members that have an identical sequency of zones, although subzone designations vary slightly between the two units. The identified lithostratigraphic divisions can be used to approximate thermal-mechanical and hydrogeologic boundaries in the field. Linking these three systems of nomenclature provides a framework within which to correlate these properties through regions of sparse data.

  15. PCDD/F and PCB in human serum of differently exposed population groups of an Italian city.

    PubMed

    Turrio-Baldassarri, Luigi; Abate, Vittorio; Battistelli, Chiara Laura; Carasi, Sergio; Casella, Marialuisa; Iacovella, Nicola; Indelicato, Annamaria; La Rocca, Cinzia; Scarcella, Carmelo; Alivernini, Silvia

    2008-08-01

    A chemical plant located in Brescia, an industrial city in North-Western Italy, produced polychlorobiphenyls (PCBs) during a 30-50 year period, causing widespread pollution of the surrounding agricultural area. This area contains several small farms, which principally produce veal meat for private consumption of the farmers' families. The pollution went undiscovered for many years, during which period contaminated food was regularly consumed. This paper reports the polychlorodibenzodioxin (PCDD), polychlorodibenzofuran (PCDF) and PCB levels of a serum sample pooled from the consumers of contaminated food, compared to six population groups of the city of Brescia. Four of these groups were selected in order to represent, respectively, the local general population and the residents of three zones of the polluted area, while the last two groups represented, respectively, the present and the former workers of the plant. One human milk sample from one of the consumers of contaminated food was also analyzed. Results show that the consumers of the contaminated food and the former workers of the plant display considerably higher levels than all other groups. The levels of general population and of all other groups were generally similar both to each other and to the range of literature values for unexposed populations. The respective contribution of PCDDs, PCDFs, mono-ortho and non-ortho PCBs (dioxin-like PCBs) to (Toxicity Equivalents) TEQ of the population groups of this study were also compared to literature data: the two groups with a high contamination level, together with the human milk sample, displayed a higher incidence of mono-ortho PCBs and a lower contribution of PCDD, possibly correlated with the source of contamination.

  16. High dose of N-acetylcysteine increase H₂O₂ and MDA levels and decrease GSH level of HUVECs exposed with malaria serum.

    PubMed

    Fitri, L E; Sardjono, T W; Simamora, D; Sumarno, R P; Setyawati, S K

    2011-04-01

    Dysfunction of endothelial cells in severe malaria may result from excessive activation of tumor necrosis factor (TNF)-α which leads to an increase in production of reactive oxygen species (ROS) and decrease of antioxidant level of endothelial cells. To investigate the effect of N-acetylcysteine (NAC) on hydrogen peroxide (H2O2), malondialdehyde (MDA) and glutathione (GSH) levels produced by endothelial cells exposed with serum of malaria falciparum patient, an in vitro model of human umbilical vein endothelial cells (HUVECs) culture was used. Sample groups were normal HUVECs (group A), HUVECs that was exposed with malaria serum without any treatment (group B), HUVECs that were exposed with malaria serum and treated with NAC 2 μM (group C), HUVECs that were exposed with malaria serum and treated with NAC 4 μM (group D), and HUVECs that were exposed with malaria serum and treated with NAC 8 μM (group E). The level of MDA was measured by thio-barbituric acid reaction assay and H2O2 level was measured by NWLSS Hydrogen Peroxyde/Peroxydase Assay kit. The level of GSH was determined by using NWLSS Glutathione Assay kit. The level of H2O2 and MDA decreased after administration of low dose of NAC. Unfortunately, increased H2O2 and MDA levels were found on HUVECs treated with high dose of NAC (8 μM). There was a positive correlation between NAC dose and H2O2 level (r= 0,603) and between NAC dose and MDA level (r= 0,721). A significant decreased level of GSH was found on HUVECs treated with high dose of NAC (p = 0,023). It can be concluded that the use of high dose of NAC as supportive therapy in severe malaria infection must be taken carefully.

  17. Smoking Rates Still High in Some Racial Groups, CDC Reports

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_160256.html Smoking Rates Still High in Some Racial Groups, CDC ... lot of progress in getting Americans to stop smoking, some groups still have high smoking rates, a ...

  18. Workplace response of companies exposed to the 9/11 World Trade Center attack: a focus-group study

    PubMed Central

    North, Carol S.; Pfefferbaum, Betty; Hong, Barry A.; Gordon, Mollie R.; Kim, You-Seung; Lind, Lisa; Pollio, David E.

    2014-01-01

    The terrorist attacks of 11 September 2001 (9/11) left workplaces in pressing need of a mental health response capability. Unaddressed emotional sequelae may be devastating to the productivity and economic stability of a company’s workforce. In the second year after the attacks, 85 employees of five highly affected agencies participated in 12 focus groups to discuss workplace mental health issues. Managers felt ill prepared to manage the magnitude and the intensity of employees’ emotional responses. Rapid return to work, provision of workplace mental health services, and peer support were viewed as contributory to emotional recovery. Formal mental health services provided were perceived as insufficient. Drawing on their post-9/11 workplace experience, members of these groups identified practical measures that they found helpful in promoting healing outside of professional mental health services. These measures, consistent with many principles of psychological first aid, may be applied by workplace leaders who are not mental health professionals. PMID:23066661

  19. Workplace response of companies exposed to the 9/11 World Trade Center attack: a focus-group study.

    PubMed

    North, Carol S; Pfefferbaum, Betty; Hong, Barry A; Gordon, Mollie R; Kim, You-Seung; Lind, Lisa; Pollio, David E

    2013-01-01

    The terrorist attacks of 11 September 2001 (9/11) left workplaces in pressing need of a mental health response capability. Unaddressed emotional sequelae may be devastating to the productivity and economic stability of a company's workforce. In the second year after the attacks, 85 employees of five highly affected agencies participated in 12 focus groups to discuss workplace mental health issues. Managers felt ill prepared to manage the magnitude and the intensity of employees' emotional responses. Rapid return to work, provision of workplace mental health services, and peer support were viewed as contributory to emotional recovery. Formal mental health services provided were perceived as insufficient. Drawing on their post-9/11 workplace experience, members of these groups identified practical measures that they found helpful in promoting healing outside of professional mental health services. These measures, consistent with many principles of psychological first aid, may be applied by workplace leaders who are not mental health professionals.

  20. High School Transfer Students: A Group Approach

    ERIC Educational Resources Information Center

    Valine, Warren J.; Amos, Louise Cleary

    1973-01-01

    A counselor's awareness of many incidents of adjustment problems among new students in a large and impersonal high school prompted an effort to make changes in the situation; the resulting program, designed to help new students is described in this article. (Author)

  1. Selecting Music for High School Pop Groups.

    ERIC Educational Resources Information Center

    Santy, Jeff

    1990-01-01

    Describes the criteria a high school music teacher used to select music for a new non-traditional class titled "Pop Band." Lists criteria that each song must have: playability, special feature, popular appeal, variety, artist's qualification, and appropriateness. Students took an active role in the decision-making process. (GG)

  2. Coronary blood flow in rats native to simulated high altitude and in rats exposed to it later in life.

    PubMed

    Turek, Z; Turek-Maischeider, M; Claessens, R A; Ringnalda, B E; Kreuzer, F

    1975-03-22

    In rats exposed to a simulated high altitude of 3500 m for their whole prenatal and postnatal life a severe cardiac hypertrophy develops. In rats born and first staying 5 weeks at sea level and then being exposed to simulated high altitude, only a unilateral right cardiac hypertrophy occurs. In both groups nutritional coronary blood flow was estimated in left ventricle, right ventricle, and septum and was compared with control animals of similar age. Coronary blood flow was measured at hypoxia in all groups. At first cardiac output was determined by the Fick principle, then 86Rb was applied and the animals were killed after 55 sec. Activity of 86Rb was measured in both cardiac ventricles and septum and the fractional uptake was calculated. According to Sapirstein (1956, 1958) the distribution of 86-RB follows the distribution of cardiac output and from both these data the nutritional blood flow to the parts of the heart may be estimated. Cardiac output was similar in rats exposed to simulated high altitude later in life ('newcomers') and in control animals, but it was significantly lower in rats born in the low pressure chamber ('natives'). Fractions of cardiac output supplying cardiac ventricles and septum in rats from both hypoxic groups were significantly higher than in control animals. In the 'natives' they were significantly higher than in the 'newcomers'. The fractions of cardiac output in both 'newcomers' and 'natives' remained significantly higher than those of the control animals, also when calculated per gram of heart tissue. Nutritional coronary blood flow (in ml/min) was higher in both ventricles and septum of the 'newcomers' and in the right ventricle of the 'natives', and lower in the septum of the 'natives', when compared with control animals. Coronary blood flow per gram of heart tissue (in ml/min.g) was significantly higher in all cardiac parts of the 'newcomers', but it was about the same in all cardiac parts of the 'natives' when compared with

  3. Reconstruction of high voltage electric burn wound with exposed shoulder joint by thoracoacromial artery perforator propeller flap.

    PubMed

    Rout, Debesh Kumar; Nayak, Bibhuti Bhusan; Choudhury, Arun Kumar; Pati, Ajit Kumar

    2014-05-01

    We describe the reconstruction of high voltage electric burn injury with exposed shoulder joint by thoracoacromial artery perforator propeller flap based on the delto-pectoral perforators of thoracoacromial artery. The successful use of this propeller flap to cover the exposed shoulder joint in a case with limited local flap options demonstrates its use as an alternative technique.

  4. High and dry: high elevations disproportionately exposed to regional climate change in Mediterranean-climate landscapes

    USGS Publications Warehouse

    McCullough, Ian M.; Davis, Frank W.; Dingman, John R.; Flint, Lorraine E.; Flint, Alan L.; Serra-Diaz, Josep M.; Syphard, Alexandra D.; Moritz, Max A.; Hannah, Lee; Franklin, Janet

    2016-01-01

    In moisture-limited, Mediterranean-climate landscapes, high elevations may experience the greatest exposure to climate change in the 21st century. High elevation species may thus be especially vulnerable to continued climate change as habitats shrink and historically energy-limited locations become increasingly moisture-limited in the future.

  5. Des-acyl ghrelin prevents heatstroke-like symptoms in rats exposed to high temperature and high humidity.

    PubMed

    Inoue, Yoshiyuki; Hayashi, Yujiro; Kangawa, Kenji; Suzuki, Yoshihiro; Murakami, Noboru; Nakahara, Keiko

    2016-02-26

    We have shown previously that des-acyl ghrelin decreases body temperature in rats through activation of the parasympathetic nervous system. Here we investigated whether des-acyl ghrelin ameliorates heatstroke in rats exposed to high temperature. Peripheral administration of des-acyl ghrelin significantly attenuated hyperthermia induced by exposure to high-temperature (35°C) together with high humidity (70-80%). Although biochemical analysis revealed that exposure to high temperature significantly increased hematocrit and the serum levels of aspartate amino transferase (AST), alanine transaminase (ALT), blood urea nitrogen (BUN), creatinine and electrolytes (Na(+), K(+), Cl(-)), most of these heatstroke-associated reactions were significantly reduced by treatment with des-acyl ghrelin. The level of des-acyl ghrelin in plasma was also found to be significantly increased under high-temperature conditions. These results suggest that des-acyl ghrelin could be useful for preventing heatstroke under high temperature condition. PMID:26773867

  6. Des-acyl ghrelin prevents heatstroke-like symptoms in rats exposed to high temperature and high humidity.

    PubMed

    Inoue, Yoshiyuki; Hayashi, Yujiro; Kangawa, Kenji; Suzuki, Yoshihiro; Murakami, Noboru; Nakahara, Keiko

    2016-02-26

    We have shown previously that des-acyl ghrelin decreases body temperature in rats through activation of the parasympathetic nervous system. Here we investigated whether des-acyl ghrelin ameliorates heatstroke in rats exposed to high temperature. Peripheral administration of des-acyl ghrelin significantly attenuated hyperthermia induced by exposure to high-temperature (35°C) together with high humidity (70-80%). Although biochemical analysis revealed that exposure to high temperature significantly increased hematocrit and the serum levels of aspartate amino transferase (AST), alanine transaminase (ALT), blood urea nitrogen (BUN), creatinine and electrolytes (Na(+), K(+), Cl(-)), most of these heatstroke-associated reactions were significantly reduced by treatment with des-acyl ghrelin. The level of des-acyl ghrelin in plasma was also found to be significantly increased under high-temperature conditions. These results suggest that des-acyl ghrelin could be useful for preventing heatstroke under high temperature condition.

  7. High energy flare physics group summary

    NASA Technical Reports Server (NTRS)

    Ryan, J. M.; Kurfess, J. D.

    1989-01-01

    The contributions of the High Energy Flare Physics Special Session in the American Astronomical Society Solar Physics Division Meeting are reviewed. Oral and poster papers were presented on observatories and instruments available for the upcoming solar maximum. Among these are the space-based Gamma Ray Observatory, the Solar Flare and Cosmic Burst Gamma Ray Experiment on the Ulysses spacecraft, the Soft X Ray Telescope on the spacecraft Solar-A, and the balloon-based Gamma Ray Imaging Device. Ground based observatories with new capabilities include the BIMA mm-wave interferometer (Univ. of California, Berkeley; Univ. of Illinois; Univ. of Maryland), Owens Valley Radio Observatory and the Very Large Array. The highlights of the various instrument performances are reported and potential data correlations and collaborations are suggested.

  8. Natural infection of guinea pigs exposed to patients with highly drug-resistant tuberculosis

    PubMed Central

    Dharmadhikari, Ashwin S.; Basaraba, Randall J.; Van Der Walt, Martie L.; Weyer, Karin; Mphahlele, Matsie; Venter, Kobus; Jensen, Paul A.; First, Melvin W.; Parsons, Sydney; McMurray, David N.; Orme, Ian M.; Nardell, Edward A.

    2012-01-01

    A natural TB infection model using guinea pigs may provide useful information for investigating differences in transmission efficiency and establishment of active disease by clinical TB strains in a highly susceptible host under controlled environmental conditions. We sought to examine the capacity of naturally transmitted multidrug-resistant M. tuberculosis to establish infection and produce active disease in guinea pigs. Guinea pigs were continuously exposed for 4 months to the exhaust air of a 6-bed multidrug-resistant tuberculosis inpatient hospital ward in South Africa. Serial tuberculin skin test reactions were measured to determine infection. All animals were subsequently evaluated for histologic disease progression at necropsy. Although 75% of the 362 exposed guinea pigs had positive skin test reactions [≥6mm], only 12% had histopathologic evidence of active disease. Reversions (≥ 6 mm change) in skin test reactivity were seen in 22% of animals, exclusively among those with reactions of 6 to 13 mm. Only two of 86 guinea pigs with reversion had histological evidence of disease compared to 47% (31/66) of guinea pigs with large, non-reverting reactions. Immunosuppression of half the guinea pigs across all skin test categories did not significantly accelerate disease progression. In guinea pigs that reverted a skin test, a second positive reaction in 27 (33%) of them strongly suggested re-infection due to ongoing exposure. These results show that a large majority of guinea pigs naturally exposed to human-source strains of multidrug-resistant tuberculosis became infected, but that many resolved their infection and a large majority failed to progress to detectable disease. PMID:21478054

  9. NO/peroxynitrite dynamics of high glucose-exposed HUVECs: chemiluminescent measurement and computational model.

    PubMed

    Potdar, Sunil; Kavdia, Mahendra

    2009-09-01

    Pathogenesis of many of diabetes-related vascular complications is associated with endothelial cell (EC) dysfunction, which is reduced bioavailability of EC-released nitric oxide (NO). Interaction dynamics of NO, superoxide (O(2)(-)) and peroxynitrite (ONOO(-)) are dependent on both their productions and consumptions through various pathways. Quantitative knowledge of these interaction dynamics in high glucose-induced EC dysfunction remains poorly understood. We developed an integrated experimental and computational approach to gain a quantitative understanding of the interactions of NO, O(2)(-) and ONOO(-) in high glucose-exposed ECs. End-products, nitrite and nitrate, were measured using a chemiluminescence analyzer. A computational biochemical reaction network model was developed to predict the effect of high glucose on ECs NO, O(2)(-) and ONOO(-). ECs NO and O(2)(-) productions increased in high glucose as evidenced by increased total NOx concentration, primarily increasing nitrate concentration. The model predicted an increase in O(2)(-) and ONOO(-) concentrations and a decrease in NO concentration in high glucose conditions. Administration of superoxide dismutase (SOD) decreased O(2)(-) concentration and increased NO concentration, thus SOD improved high glucose-induced changes in these interactions. An important finding of this study was that the NO bioavailability decreased in high glucose conditions even though NO production of EC increased. The integrated approach provides a framework to predict NO, O(2)(-) and ONOO(-) concentrations and productions that are difficult to measure in one experiment and will be useful in further EC dysfunction studies. PMID:19362569

  10. Cleavable ester linked magnetic nanoparticles for labeling of solvent exposed primary amine groups of peptides/proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to study the solvent exposed lysine residues of peptides/proteins, we previously reported disulfide linked N-hydrosuccinimide ester modified silica coated iron oxide magnetic nanoparticles (NHS-SS-SiO2@Fe3O4 MNPs). The presence of a disulfide bond in the linker limits the use of disulfide r...

  11. Micronuclei induction in human fibroblasts exposed in vitro to Los Alamos high-energy neutrons

    NASA Astrophysics Data System (ADS)

    Gersey, Brad; Sodolak, John; Hada, Megumi; Saganti, Prem; Wilkins, Richard; Cucinotta, Francis; Wu, Honglu

    High-energy secondary neutrons, produced by the interaction of galactic cosmic rays with the atmosphere, spacecraft structure and planetary surfaces, contribute to a significant fraction to the dose equivalent in crew members and passengers during commercial aviation travel, and astronauts in space missions. The Los Alamos Nuclear Science Center (LANSCE) neutron facility's ICE House 30L beamline is known to generate neutrons that simulate the secondary neutron spectra of earth's atmosphere. The neutron spectrum is also similar to that measured onboard spacecraft like the MIR and International Space Station (ISS). To evaluate the biological damage, we exposed human fibroblasts in vitro to the LANSCE neutron beams without degrader at an entrance dose rate of 25 mGy/h and analyzed the micronuclei (MN) induction. The cells were also placed behind a 9.9 cm water column to study the effect of shielding in the protection of neutron induced damages. It was found that the dose response in the MN frequency was linear for the samples with and without shielding and the slope of the MN yield behind the shielding was reduced by a factor of 3.5. Compared to the MN induction in human fibroblasts exposed to a γ source at a similar low dose rate, the RBE was found to be 16.7 and 10.0 for the neutrons without and with the 9.9 cm water shielding, respectively.

  12. The Exposed Moho In the Kohistan Arc: Seismic Properties At High Temperature And Pressure

    NASA Astrophysics Data System (ADS)

    Burg, J.; Burlini, L.

    2005-12-01

    The exposed crustal and mantle section in the Kohistan paleo-island arc in Pakistan is one of the most continuous and fresh example of exposed Moho. The geometrical relationships between mantle rocks and lower crustal intrusives and metamorphites are well preserved, making this section a natural laboratory for geological and geophysical investigation. In this study we investigated the relationships between the petrological and seismic Moho at geological relevant conditions, by measuring the speed of ultrasounds in rocks samples at high pressure and temperature. The compressional wave velocities were measured at confining pressures of up to 0.5 GPa and temperatures of up to 1200°C in an internally heated gas medium apparatus (Paterson rig) in three orthogonal cores per sample, cut parallel or normal to the mineral lineation and the foliation normal. Measurements were done on dunites, pyroxenites and wherlites representative of the upper mantle; on garnetites, amphibolites and gabbros representative of the lower crust. Interestingly, both the pyroxenite and the garnetite developed partial melting at temperatures greater than 1100°C at about 0.5 GPa confining pressure. During the melting we did not observed a remarkable reduction in the seismic velocities, but a remarkable reduction in the seismic amplitude, suggesting a large variation in seismic attenuation. The geological implication of our findings is that at (or above) the Moho, the presence of partially molten rocks might be detected by anomalies in the P-wave attenuation.

  13. Micronuclei Induction in Human Fibroblasts Exposed In Vitro to Los Alamos High-Energy Neutrons

    NASA Technical Reports Server (NTRS)

    Gersey, Brad; Sodolak, John; Hada, Megumi; Saganti, Prem; Wilkins, Richard; Cucinotta, Francis; Wu, Honglu

    2006-01-01

    High-energy secondary neutrons, produced by the interaction of galactic cosmic rays with the atmosphere, spacecraft structure and planetary surfaces, contribute to a significant fraction to the dose equivalent in crew members and passengers during commercial aviation travel, and astronauts in space missions. The Los Alamos Nuclear Science Center (LANSCE) neutron facility#s ICE House 30L beamline is known to generate neutrons that simulate the secondary neutron spectra of earth#s atmosphere. The neutron spectrum is also similar to that measured onboard spacecraft like the MIR and International Space Station (ISS). To evaluate the biological damage, we exposed human fibroblasts in vitro to the LANSCE neutron beams without degrader at an entrance dose rate of 25 mGy/hr and analyzed the micronuclei (MN) induction. The cells were also placed behind a 9.9 cm water column to study effect of shielding in the protection of neutron induced damages. It was found that the dose response in the MN frequency was linear for the samples with and without shielding and the slope of the MN yield behind the shielding was reduced by a factor of 3.5. Compared to the MN induction in human fibroblasts exposed to a gamma source at a low dose rate, the RBE was found to be 16.7 and 10.0 for the neutrons without and with 9.9 cm water shielding, respectively.

  14. Vapor Corrosion Response of Low Carbon Steel Exposed to Simulated High Level Radioactive Waste

    SciTech Connect

    Wiersma, B

    2006-01-26

    A program to resolve the issues associated with potential vapor space corrosion and liquid/air interface corrosion in the Type III high level waste tanks is in place. The objective of the program is to develop understanding of vapor space (VSC) and liquid/air interface (LAIC) corrosion to ensure a defensible technical basis to provide accurate corrosion evaluations with regard to vapor space and liquid/air interface corrosion. The results of the FY05 experiments are presented here. The experiments are an extension of the previous research on the corrosion of tank steel exposed to simple solutions to corrosion of the steel when exposed to complex high level waste simulants. The testing suggested that decanting and the consequent residual species on the tank wall is the predominant source of surface chemistry on the tank wall. The laboratory testing has shown that at the boundary conditions of the chemistry control program for solutions greater than 1M NaNO{sub 3}{sup -}. Minor and isolated pitting is possible within crevices in the vapor space of the tanks that contain stagnant dilute solution for an extended period of time, specifically when residues are left on the tank wall during decanting. Liquid/air interfacial corrosion is possible in dilute stagnant solutions, particularly with high concentrations of chloride. The experimental results indicate that Tank 50 would be most susceptible to the potential for liquid/air interfacial corrosion or vapor space corrosion, with Tank 49 and 41 following, since these tanks are nearest to the chemistry control boundary conditions. The testing continues to show that the combination of well-inhibited solutions and mill-scale sufficiently protect against pitting in the Type III tanks.

  15. Transcriptome Profile Analysis of Breast Muscle Tissues from High or Low Levels of Atmospheric Ammonia Exposed Broilers (Gallus gallus)

    PubMed Central

    Sa, Renna; Zhong, Ruqing; Xing, Huan; Zhang, Hongfu

    2016-01-01

    Atmospheric ammonia is a common problem in poultry industry. High concentrations of aerial ammonia cause great harm to broilers' health and production. For the consideration of human health, the limit exposure concentration of ammonia in houses is set at 25 ppm. Previous reports have shown that 25 ppm is still detrimental to livestock, especially the gastrointestinal tract and respiratory tract, but the negative relationship between ammonia exposure and the tissue of breast muscle of broilers is still unknown. In the present study, 25 ppm ammonia in poultry houses was found to lower slaughter performance and breast yield. Then, high-throughput RNA sequencing was utilized to identify differentially expressed genes in breast muscle of broiler chickens exposed to high (25 ppm) or low (3 ppm) levels of atmospheric ammonia. The transcriptome analysis showed that 163 genes (fold change ≥ 2 or ≤ 0.5; P-value < 0.05) were differentially expressed between Ammonia25 (treatment group) and Ammonia3 (control group), including 96 down-regulated and 67 up-regulated genes. qRT-PCR analysis validated the transcriptomic results of RNA sequencing. Gene Ontology (GO) functional annotation analysis revealed potential genes, processes and pathways with putative involvement in growth and development inhibition of breast muscle in broilers caused by aerial ammonia exposure. This study facilitates understanding of the genetic architecture of the chicken breast muscle transcriptome, and has identified candidate genes for breast muscle response to atmospheric ammonia exposure. PMID:27611572

  16. Transcriptome Profile Analysis of Breast Muscle Tissues from High or Low Levels of Atmospheric Ammonia Exposed Broilers (Gallus gallus).

    PubMed

    Yi, Bao; Chen, Liang; Sa, Renna; Zhong, Ruqing; Xing, Huan; Zhang, Hongfu

    2016-01-01

    Atmospheric ammonia is a common problem in poultry industry. High concentrations of aerial ammonia cause great harm to broilers' health and production. For the consideration of human health, the limit exposure concentration of ammonia in houses is set at 25 ppm. Previous reports have shown that 25 ppm is still detrimental to livestock, especially the gastrointestinal tract and respiratory tract, but the negative relationship between ammonia exposure and the tissue of breast muscle of broilers is still unknown. In the present study, 25 ppm ammonia in poultry houses was found to lower slaughter performance and breast yield. Then, high-throughput RNA sequencing was utilized to identify differentially expressed genes in breast muscle of broiler chickens exposed to high (25 ppm) or low (3 ppm) levels of atmospheric ammonia. The transcriptome analysis showed that 163 genes (fold change ≥ 2 or ≤ 0.5; P-value < 0.05) were differentially expressed between Ammonia25 (treatment group) and Ammonia3 (control group), including 96 down-regulated and 67 up-regulated genes. qRT-PCR analysis validated the transcriptomic results of RNA sequencing. Gene Ontology (GO) functional annotation analysis revealed potential genes, processes and pathways with putative involvement in growth and development inhibition of breast muscle in broilers caused by aerial ammonia exposure. This study facilitates understanding of the genetic architecture of the chicken breast muscle transcriptome, and has identified candidate genes for breast muscle response to atmospheric ammonia exposure. PMID:27611572

  17. Gene expression profile of Jurkat cells exposed to high power terahertz radiation

    NASA Astrophysics Data System (ADS)

    Grundt, Jessica E.; Roth, Caleb C.; Rivest, Benjamin D.; Doroski, Michael L.; Payne, Jason; Ibey, Bennett L.; Wilmink, Gerald J.

    2011-03-01

    Terahertz (THz) radiation sources are now being used in a host of military, defense, and medical applications. Widespread employment of these applications has prompted concerns regarding the health effects associated with THz radiation. In this study, we examined the gene expression profile of mammalian cells exposed to THz radiation. We hypothesized that if THz radiation couples directly to cellular constituents, then exposed cells may express a specific gene expression profile indicative of ensuing damage. To test this hypothesis, Jurkat cells were irradiated with a molecular gas THz laser (2.52 THz, 636 mWcm-2, durations: 5, 10, 20, 30, 40, or 50 minutes). Viability was assessed 24 h post-exposure using MTT assays, and gene expression profiles were evaluated 4 h post-exposure using mRNA microarrays. Comparable analyses were also performed for hyperthermic positive controls (44°C for 40 minutes). We found that cellular temperatures increased by ~6 °C during THz exposures. We also found that cell death increased with exposure duration, and the median lethal dose (LD50) was calculated to be ~44 minutes. The microarray data showed that THz radiation induced the transcriptional activation of genes associated with cellular proliferation, differentiation, transcriptional activation, chaperone protein stabilization, and apoptosis. For most genes, we found that the magnitude of differential expression was comparable for both the THz and thermal exposure groups; however, several genes were specifically activated by the THz exposure. These results suggest that THz radiation may elicit effects that are not exclusively due to the temperature rise created during THz exposures (i.e. thermal effects). In future work, we plan to verify the results of our microarray experiments using qPCR techniques.

  18. Defective titanium dioxide single crystals exposed by high-energy {001} facets for efficient oxygen reduction

    PubMed Central

    Pei, Dan-Ni; Gong, Li; Zhang, Ai-Yong; Zhang, Xing; Chen, Jie-Jie; Mu, Yang; Yu, Han-Qing

    2015-01-01

    The cathodic material plays an essential role in oxygen reduction reaction for energy conversion and storage systems. Titanium dioxide, as a semiconductor material, is usually not recognized as an efficient oxygen reduction electrocatalyst owning to its low conductivity and poor reactivity. Here we demonstrate that nano-structured titanium dioxide, self-doped by oxygen vacancies and selectively exposed with the high-energy {001} facets, exhibits a surprisingly competitive oxygen reduction activity, excellent durability and superior tolerance to methanol. Combining the electrochemical tests with density-functional calculations, we elucidate the defect-centred oxygen reduction reaction mechanism for the superiority of the reductive {001}-TiO2−x nanocrystals. Our findings may provide an opportunity to develop a simple, efficient, cost-effective and promising catalyst for oxygen reduction reaction in energy conversion and storage technologies. PMID:26493365

  19. Deuterium retention and surface modifications of nanocrystalline tungsten films exposed to high-flux plasma

    NASA Astrophysics Data System (ADS)

    `t Hoen, M. H. J.; Dellasega, D.; Pezzoli, A.; Passoni, M.; Kleyn, A. W.; Zeijlmans van Emmichoven, P. A.

    2015-08-01

    Deuterium retention studies are presented for nanostructured tungsten films exposed to high-flux deuterium plasmas. Thin tungsten films of ∼1 μm thickness were deposited with pulsed laser deposition (PLD) on bulk tungsten. Surface modifications were studied with scanning electron microscopy and deuterium retention with thermal desorption spectroscopy. Three types of PLD films with different densities and crystallinity were studied after exposure to deuterium plasmas. The surface temperature ranged from about 460 K at the periphery to about 520 K in the centre of the targets. The films withstand the intense plasma exposure well and maintain their overall integrity. An increase of deuterium retention is observed with decreasing tungsten density and crystallite size. We found that the filling of these thin films with deuterium is significantly faster than for pre-damaged polycrystalline tungsten. We observed formation of micrometer-sized blisters as well as structures on the nanometer scale, both depending on the layer type.

  20. Defective titanium dioxide single crystals exposed by high-energy {001} facets for efficient oxygen reduction.

    PubMed

    Pei, Dan-Ni; Gong, Li; Zhang, Ai-Yong; Zhang, Xing; Chen, Jie-Jie; Mu, Yang; Yu, Han-Qing

    2015-01-01

    The cathodic material plays an essential role in oxygen reduction reaction for energy conversion and storage systems. Titanium dioxide, as a semiconductor material, is usually not recognized as an efficient oxygen reduction electrocatalyst owning to its low conductivity and poor reactivity. Here we demonstrate that nano-structured titanium dioxide, self-doped by oxygen vacancies and selectively exposed with the high-energy {001} facets, exhibits a surprisingly competitive oxygen reduction activity, excellent durability and superior tolerance to methanol. Combining the electrochemical tests with density-functional calculations, we elucidate the defect-centred oxygen reduction reaction mechanism for the superiority of the reductive {001}-TiO2-x nanocrystals. Our findings may provide an opportunity to develop a simple, efficient, cost-effective and promising catalyst for oxygen reduction reaction in energy conversion and storage technologies.

  1. Recovery time of high temperature superconducting tapes exposed in liquid nitrogen

    NASA Astrophysics Data System (ADS)

    Sheng, Jie; Zeng, Weina; Yao, Zhihao; Zhao, Anfeng; Hu, Daoyu; Hong, Zhiyong

    2016-08-01

    The recovery time is a crucial parameter to high temperature superconducting tapes, especially in power applications. The cooperation between the reclosing device and the superconducting facilities mostly relies on the recovery time of the superconducting tapes. In this paper, a novel method is presented to measure the recovery time of several different superconducting samples. In this method criterion used to judge whether the sample has recovered is the liquid nitrogen temperature, instead of the critical temperature. An interesting phenomenon is observed during the testing of superconducting samples exposed in the liquid nitrogen. Theoretical explanations of this phenomenon are presented from the aspect of heat transfer. Optimization strategy of recovery characteristics based on this phenomenon is also briefly discussed.

  2. Retention of nanocrystalline WNx layers exposed to high-fluence deuterium plasmas

    NASA Astrophysics Data System (ADS)

    Vassallo, E.; Caniello, R.; Angella, G.; Dellasega, D.; Granucci, G.; Mellera, V.; Minelli, D.; Pedroni, M.; Ricci, D.; Rigato, V.; Passoni, M.

    2015-11-01

    For high-power plasma operation regimes in tokamak fusion devices the power load onto W divertor plates must be kept below acceptable limits for materials. N2 gas is likely to be used to reduce the power load. However, because of erosion phenomena, WNx compounds will be produced in the divertor and tritium retention is issue of concern. We report recent experiments using the GYM linear plasma device that examined D retention in WNx compounds exposed to D plasma at divertor relevant fluence (∼1024 m-2). It is shown that WNx compounds with different nitrogen concentration have very similar D retention, lower than the case of the tungsten without nitrogen and in any case lower than the acceptable limit for operation in ITER.

  3. SCC Initiation in Alloy 600 Heat Affected Zones Exposed to High Temperature Water

    SciTech Connect

    E Richey; DS Morton; RA Etien; GA Young; RB Bucinell

    2006-11-03

    Studies have shown that grain boundary chromium carbides improve the stress corrosion cracking (SCC) resistance of nickel based alloys exposed to high temperature, high purity water. However, thermal cycles from welding can significantly alter the microstructure of the base material near the fusion line. In particular, the heat of welding can solutionize grain boundary carbides and produce locally high residual stresses and strains, reducing the SCC resistance of the Alloy 600 type material in the heat affected zone (HAZ). Testing has shown that the SCC growth rate in Alloy 600 heat affected zone samples can be {approx}30x faster than observed in the Alloy 600 base material under identical testing conditions due to fewer intergranular chromium rich carbides and increased plastic strain in the HAZ [1, 2]. Stress corrosion crack initiation tests were conducted on Alloy 600 HAZ samples at 360 C in hydrogenated, deaerated water to determine if these microstructural differences significantly affect the SCC initiation resistance of Alloy 600 heat affected zones compared to the Alloy 600 base material. Alloy 600 to EN82H to Alloy 600 heat-affected-zone (HAZ) specimens where fabricated from an Alloy 600 to Alloy 600 narrow groove weld with EN82H filler metal. The approximate middle third of the specimen gauge region was EN82H such that each specimen had two HAZ regions. Tests were conducted with in-situ monitored smooth tensile specimens under a constant load, and a direct current electric potential drop was used for in-situ detection of SCC. Test results suggest that the SCC initiation resistance of Alloy 600 and its weld metal follows the following order: EN82H > Alloy 600 HAZ > Alloy 600. The high SCC initiation resistance observed to date in Alloy 600 heat affected zones compared to wrought Alloy 600 is unexpected based on the microstructure of HAZ versus wrought material and based on prior SCC growth rate studies. The observed behavior for the HAZ specimens is likely

  4. Distribution of Chromosome Breakpoints in Human Epithelial Cells Exposed to Low- and High-LET Radiations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, Francis; Wu, Honglu

    2009-01-01

    The advantage of the multicolor banding in situ hybridization (mBAND) technique is not only its ability to identify simultaneously both inter- and intrachromosome exchanges, but also the ability to measure the breakpoint location along the length of the chromosome in a precision that is unmatched with other traditional banding techniques. Breakpoints on specific regions of a chromosome have been known to associate with specific cancers. The breakpoint distribution in cells after low- and high-LET radiation exposures will also provide the data for biophysical modeling of the chromatin structure, as well as the data for the modeling the formation of radiation-induced chromosome aberrations. In a series of experiments, we studied low- and high-LET radiation-induced chromosome aberrations using the mBAND technique with chromosome 3 painted in 23 different colored bands. Human epithelial cells (CH1 84B5F5/M10) were exposed in vitro to Cs- 137 rays at both low and high dose rates, secondary neutrons with a broad energy spectrum at a low dose rate and 600 MeV/u Fe ions at a high dose rate. The data of both inter- and intrachromosome aberrations involving the painted chromosome have been reported previously. Here we present data of the location of the chromosome breaks along the length of chromosome 3 in the cells after exposures to each of the four radiation scenarios. In comparison to the expected breakpoint distribution based on the length of the bands, the observed distribution appeared to be non-random for both the low- and high-LET radiations. In particular, hot spots towards both ends of the chromosome were found after low-LET irradiations of either low or high dose rates. For both high-LET radiation types (Fe ions and neutrons), the breakpoint distributions were similar, and were much smoother than that for low-LET radiation. The dependence of the breakpoint distribution on the radiation quality requires further investigations.

  5. Tensile Properties and Swelling Behavior of Sealing Rubber Materials Exposed to High-Pressure Hydrogen Gas

    NASA Astrophysics Data System (ADS)

    Yamabe, Junichiro; Nishimura, Shin

    Rubber O-rings exposed to high-pressure hydrogen gas swell, and the volume increase induced by swelling influences tensile properties of the O-rings. Samples of nonfilled (NF), carbon black-filled (CB), and silica-filled (SC) sulfur-vulcanized acrylonitrile-butadiene rubber were exposed to hydrogen at 30 °C and pressures of up to 100 MPa, and the effect of hydrogen exposure on the volume increase, hydrogen content, and tensile properties was investigated. The residual hydrogen content, measured 35 minutes after decompression, increased with increasing hydrogen pressure in the range 0.7-100 MPa for all three samples. In contrast, the volumes of NF, CB, and SC barely changed at pressures below 10 MPa, whereas they increased at pressures above 10 MPa. This nonlinear volume increase is probably related to the free volume of the rubber structure. The volume increase of the CB and SC samples was smaller than that of the NF samples, possibly because of the superior tensile properties of CB and SC. As the volumes of the NF, CB, and SC samples increased, their tensile elastic moduli decreased as a result of a decrease in crosslink density and elongation by volume increase. Although the true fracture stress of NF was barely dependent on the volume of the specimen, those of CB and SC clearly decreased as the volume increased. The decrease in the true fracture stress of CB and SC was related to the volume increase by swelling, showing that the boundary structure between the filler and the rubber matrix was changed by the volume increase.

  6. Effects of High-Butterfat Diet on Embryo Implantation in Female Rats Exposed to Bisphenol A.

    PubMed

    Martinez, Alan M; Cheong, Ana; Ying, Jun; Xue, Jingchuan; Kannan, Kurunthachalam; Leung, Yuet-Kin; Thomas, Michael A; Ho, Shuk-Mei

    2015-12-01

    Bisphenol A (BPA) is an endocrine disruptor associated with poor pregnancy outcomes in human and rodents. The effects of butterfat diets on embryo implantation and whether it modifies BPA's actions are currently unknown. We aimed to determine the effects of butterfat diet on embryo implantation success in female rats exposed to an environmentally relevant dose of BPA. Female Sprague-Dawley rats were exposed to dietary butterfat (10% or 39% kcal/kg body weight [BW]) in the presence or absence of BPA (250 μg/kg BW) or ethinylestradiol (0.1 μg/kg BW) shortly before and during pregnancy to assess embryo implantation potentials by preimplantation development and transport, in vitro blastulation, outgrowth, and implantation. On gestational day (GD) 4.5, rats treated with BPA alone had higher serum total BPA level (2.3-3.7 ng/ml). They had more late-stage preimplantation embryos, whereas those receiving high butterfat (HBF) diet had the most advanced-stage embryos; dams cotreated with HBF and BPA had the most number of advanced embryos. BPA markedly delayed embryo transport to the uterus, but neither amount of butterfat had modifying effects. An in vitro implantation assay showed HBF doubled the outgrowth area, with BPA having no effect. In vivo, BPA reduced the number of implanted embryos on GD8, and cotreatment with HBF eliminated this adverse effect. HBF diet overall resulted in more and larger GD8 embryos. This study reveals the implantation disruptive effects of maternal exposure to an environmentally relevant dose of BPA and identifies HBF diet as a modifier of BPA in promoting early embryonic health.

  7. Porosity of UHPFRC exposed to high temperatures determined by different techniques

    NASA Astrophysics Data System (ADS)

    Korecký, Tomáš; Pokorný, Jaroslav; Fořt, Jan; Čítek, David; Pavlík, Zbyšek

    2016-07-01

    The pore system characterization of an Ultra High Performance Fibre Reinforced Concrete (UHPFRC) exposed to the elevated temperatures is presented in the paper. The porosity and pore size distribution of building materials are of the particular importance because of their clear effect on durability and service life of structural elements and buildings. Material characteristics as mechanical, thermal and hygric properties are strongly dependent on pore system. For porosity measurement, several techniques having specific advantages or disadvantages with respect to the pore size are available. In building materials research, usage of Mercury Intrusion Porosimetry (MIP) with range of the detected pores up to 100 µm is the most common. Nevertheless, in practical measurements, the differences between the porosity values determined by helium pycnometry and MIP are usually observed. It can be attributed to the presence of pores bigger than 100 µm. Based on the literature analysis it is evident that the porosity increases with the amount of fibres used since fibres application reduces workability of fresh mixture and thus cause heterogeneities and microcavities in material microstructure and interfacial transition zone between fibres, aggregates and cement paste. Therefore, the Optical Porosimetry (OP) based on an image analysis is presented in the paper as a suitable supplemental method for classification number, size and shape of bigger pores. At first, porosity is investigated on samples without temperature loading. Then, on samples which are exposed to the temperatures of 400, 800, and 1000 °C respectively. Pores size distribution is studied using mercury intrusion porosimeters Pascal 140 and 440. Images are captured by an optical microscope with an attached digital camera. The obtained results show necessity to apply the combined technique for the assessment of the porosity value.

  8. Excretion of hexachlorobenzene and metabolites in feces in a highly exposed human population.

    PubMed Central

    To-Figueras, J; Barrot, C; Sala, M; Otero, R; Silva, M; Ozalla, M D; Herrero, C; Corbella, J; Grimalt, J; Sunyer, J

    2000-01-01

    A set of 53 individuals from a population highly exposed to airborne hexachlorobenzene (HCB) were selected to study the elimination kinetics of this chemical in humans. The volunteers provided blood, 24-hr urine, and feces samples for analysis of HCB and metabolites. The serum HCB concentrations ranged from 2.4 to 1,485 ng/mL (mean +/- SD, 124 +/- 278), confirming that this human population has the highest HCB blood levels ever reported. All analyzed feces samples contained unchanged HCB (range, 11-3,025 ng/g dry weight; mean +/- SD, 395 +/- 629). The HCB concentration in feces strongly correlated with HCB in serum (r = 0.85; p < 0.001), suggesting an equilibrium in feces/serum that is compatible with a main pulmonary entrance of the chemical and low intestinal excretion of nonabsorbed foodborne HCB. The equilibrium is also compatible with a nonbiliary passive transfer of the chemical to the intestinal lumen. Two HCB main metabolites, pentachlorophenol (PCP) and pentachlorobenzenethiol (PCBT), were detected in 51% and 54% of feces samples, respectively. All urine samples contained PCP and PCBT, confirming the conclusions of a previous study [Environ Health Perspect 105:78-83 (1997)]. The comparison between feces and urine showed that whereas daily urinary elimination of metabolites may account for 3% of total HCB in blood, intestinal excretion of unchanged HCB may account for about 6%, thus showing the importance of metabolism in the overall elimination of HCB. The elimination of HCB and metabolites by both routes, however, appears to be very small (< 0.05%/day) as compared to the estimated HCB adipose depots. Features of HCB kinetics that we present in this study, i.e., nonsaturated intestinal elimination of HCB and excretion in feces and urine of inert glutathione derivatives, may explain, in part, the absence of porphyria cutanea in this human population heavily exposed to HCB. Images Figure 1 Figure 2 PMID:10903610

  9. Manganese oxide-induced strategy to high-performance iron/nitrogen/carbon electrocatalysts with highly exposed active sites

    NASA Astrophysics Data System (ADS)

    Sun, Tao; Wu, Qiang; Zhuo, Ou; Jiang, Yufei; Bu, Yongfeng; Yang, Lijun; Wang, Xizhang; Hu, Zheng

    2016-04-01

    Iron/nitrogen/carbon (Fe/N/C) catalyst is so far the most promising non-precious metal electrocatalyst for oxygen reduction reaction (ORR) in acidic medium, whose performance depends closely on the synthesis chemistry. Herein, we report a MnOx-induced strategy to construct the Fe/N/C with highly exposed Fe-Nx active sites, which involves the uniform spreading of polyaniline on hierarchical N-doped carbon nanocages by a reactive-template polymerization, followed by the successive iron incorporation and polyaniline pyrolysis. The resulting Fe/N/C demonstrates an excellent ORR performance, including an onset potential of 0.92 V (vs. RHE), four electron selectivity, superb stability and immunity to methanol crossover. The excellent performance is well correlated with the greatly enhanced surface active sites of the catalyst stemming from the unique MnOx-induced strategy. This study provides an efficient approach for exploring the advanced ORR electrocatalysts by increasing the exposed active sites.Iron/nitrogen/carbon (Fe/N/C) catalyst is so far the most promising non-precious metal electrocatalyst for oxygen reduction reaction (ORR) in acidic medium, whose performance depends closely on the synthesis chemistry. Herein, we report a MnOx-induced strategy to construct the Fe/N/C with highly exposed Fe-Nx active sites, which involves the uniform spreading of polyaniline on hierarchical N-doped carbon nanocages by a reactive-template polymerization, followed by the successive iron incorporation and polyaniline pyrolysis. The resulting Fe/N/C demonstrates an excellent ORR performance, including an onset potential of 0.92 V (vs. RHE), four electron selectivity, superb stability and immunity to methanol crossover. The excellent performance is well correlated with the greatly enhanced surface active sites of the catalyst stemming from the unique MnOx-induced strategy. This study provides an efficient approach for exploring the advanced ORR electrocatalysts by increasing the

  10. Body and organ weights of rats exposed to carbon monoxide at high altitude.

    PubMed

    McGrath, J J

    1988-01-01

    Although chronic exposure to carbon monoxide (CO) or high altitude produces pronounced cardiovascular changes in humans as well as animals, there is little information on the effects elicited by these stressors combined. Theoretical considerations, as well as data from acute studies, suggest that CO inhaled at high altitude may be more detrimental than CO inhaled at low altitude. The purpose of these studies was to construct a system in which CO and altitude could be controlled precisely, and to investigate the effects of continuous exposure to CO and high altitude on body weights and hematocrit ratios, as well as heart, spleen, adrenals, kidneys, and pituitary weights. Male, laboratory rats were exposed for 6 wk in steel barometric chambers to (1) 100 ppm CO, (2) 15,000 ft simulated high altitude (SHA), and (3) CO at SHA. Altitude was simulated by a system of gate valves and a vacuum pump, and measured by an altimeter. CO, from high-pressure cylinders, was introduced into the air supplying each chamber through a mass flow controller and measured by a nondispersive infrared (NDIR) analyzer. Although SHA had no affect on left ventricle plus septum (LV + S), adrenal, spleen, or kidney weights, SHA decreased body weights, and increased hematocrit ratios, as well as right ventricle (RV), total heart (HT), and pituitary weights. CO had no affect on body weights, RV, HT, adrenal, spleen, or kidney weights, but CO increased hematocrit ratios and LV + S weights. There was no significant interaction between SHA and CO on any parameter except kidney weight. These results indicate that, in general, the effects produced by 15,000 ft SHA are not intensified by exposure to 100 ppm CO. PMID:3351978

  11. Prediction of Ablation Rates from Solid Surfaces Exposed to High Temperature Gas Flow

    NASA Technical Reports Server (NTRS)

    Akyuzlu, Kazim M.; Coote, David

    2013-01-01

    A mathematical model and a solution algorithm is developed to study the physics of high temperature heat transfer and material ablation and identify the problems associated with the flow of hydrogen gas at very high temperatures and velocities through pipes and various components of Nuclear Thermal Rocket (NTR) motors. Ablation and melting can be experienced when the inner solid surface of the cooling channels and the diverging-converging nozzle of a Nuclear Thermal Rocket (NTR) motor is exposed to hydrogen gas flow at temperatures around 2500 degrees Kelvin and pressures around 3.4 MPa. In the experiments conducted on typical NTR motors developed in 1960s, degradation of the cooling channel material (cracking in the nuclear fuel element cladding) and in some instances melting of the core was observed. This paper presents the results of a preliminary study based on two types of physics based mathematical models that were developed to simulate the thermal-hydrodynamic conditions that lead to ablation of the solid surface of a stainless steel pipe exposed to high temperature hydrogen gas near sonic velocities. One of the proposed models is one-dimensional and assumes the gas flow to be unsteady, compressible and viscous. An in-house computer code was developed to solve the conservations equations of this model using a second-order accurate finite-difference technique. The second model assumes the flow to be three-dimensional, unsteady, compressible and viscous. A commercial CFD code (Fluent) was used to solve the later model equations. Both models assume the thermodynamic and transport properties of the hydrogen gas to be temperature dependent. In the solution algorithm developed for this study, the unsteady temperature of the pipe is determined from the heat equation for the solid. The solid-gas interface temperature is determined from an energy balance at the interface which includes heat transfer from or to the interface by conduction, convection, radiation, and

  12. Raman and electron microscopy analysis of carbon nanotubes exposed to high power laser irradiance

    SciTech Connect

    Ramadurai, Krishna; Cromer, Christopher L.; Lehman, John H.; Dillon, Anne C.; Mahajan, Roop L.

    2009-05-01

    High power laser radiometry requires efficient and damage-resistant detectors. The current study explores the evolving nature of carbon nanotube coatings for such detectors upon their exposure to incrementally increasing laser power levels. Electron microscopy images along with the D-band to G-band intensity ratios from the Raman spectra from eight irradiance levels are used to evaluate changes before and after the exposure. Electron microscopy images of the exposed multiwalled carbon nanotubes revealed the formation of intermittent pockets of moundlike structures at high power densities exceeding 11 kW/cm{sup 2}. Raman spectroscopy measurements also demonstrated higher values for the ratio of the D-band intensity to that of the G-band, suggesting the possible transformation of nanotubes into structurally different forms of carbon. Exposure to a sample of single-walled nanotubes did not demonstrate the evolution of structural changes, which could be due in part to the higher irradiance levels relative to the damage threshold, employed in the experiment.

  13. High transmittance in-plane switching liquid crystal mode using double-exposed UV alignment method

    NASA Astrophysics Data System (ADS)

    Mun, Byung-June; Cho, Jung-Ho; Lee, Joun Ho; Kim, Byeong Koo; Choi, Hyun Chul; Lee, Seung Hee; Kang, Bongsoon; Lee, Gi-Dong

    2015-02-01

    In general, the super in-plane switching (S-IPS) liquid crystal (LC) mode is widely used for LCD applications because of its wide-viewing properties. However, it can also diminish the aperture ratio in active areas due to the zigzag pattern. In this paper, we proposed an IPS LC mode that has wide-viewing properties even if the stripe-patterned electrodes, which can provide a high transmittance property, are applied using the double-exposed UV alignment method to the upper/lower domain of the active area. The initial alignment direction of the upper/lower domain was optimized with simple experiments and we achieved both the superior dark level in the initial mode and wide-viewing properties in the applied voltage mode. As a result, we obtained an increased aperture ratio of about 10% and a higher optical transmittance of 15% compared to the conventional S-IPS LC cell because of the high aperture ratio without any optical loss of the initial dark state and viewing angle property.

  14. Roughening and reflection performance of molybdenum coatings exposed to a high-flux deuterium plasma

    NASA Astrophysics Data System (ADS)

    Eren, B.; Marot, L.; Ryzhkov, I. V.; Lindig, S.; Houben, A.; Wisse, M.; Skoryk, O. O.; Oberkofler, M.; Voitsenya, V. S.; Linsmeier, Ch.; Meyer, E.

    2013-11-01

    Optical diagnostic systems of ITER are foreseen to include metallic, plasma-facing, electromagnetic radiation reflecting components called first mirrors (FMs). Molybdenum coatings are important candidates for these components. Depending on the local plasma parameters of the reactor, the mirrors may be under net erosion or deposition conditions. In this work, we exposed molybdenum coatings to a high-flux deuterium plasma in order to test their roughening limits under erosion conditions. The high energy of deuterium ions (500 eV on average) results in more vigorous roughening of the surface compared with lower energy ions (200 eV). Longer exposure (3 × 1020 ions cm-2) of the 200 eV ions results in only a slightly increased roughness compared with shorter exposure (6.8 × 1019 ions cm-2). Both phenomena match to the theory regarding roughening dynamics of physical sputtering. A comparison of results in this work with previous studies gives support to the hypothesis that roughening is flux and temperature dependent. Partial delamination of the coatings is observed upon exposure at room temperature, but not at an elevated temperature (200 °C). In summary, Mo coatings will remain functional in the ITER environment under the expected conditions. However, changes in the expected conditions such as 500 eV mean energy of impinging charge exchange neutrals or <100 °C surface temperature of the mirrors can lead to gradual or sudden failure of the coatings.

  15. The impact of humidity on evaporative cooling in small desert birds exposed to high air temperatures.

    PubMed

    Gerson, Alexander R; Smith, Eric Krabbe; Smit, Ben; McKechnie, Andrew E; Wolf, Blair O

    2014-01-01

    Environmental temperatures that exceed body temperature (Tb) force endothermic animals to rely solely on evaporative cooling to dissipate heat. However, evaporative heat dissipation can be drastically reduced by environmental humidity, imposing a thermoregulatory challenge. The goal of this study was to investigate the effects of humidity on the thermoregulation of desert birds and to compare the sensitivity of cutaneous and respiratory evaporation to reduced vapor density gradients. Rates of evaporative water loss, metabolic rate, and Tb were measured in birds exposed to humidities ranging from ∼2 to 30 g H2O m(-3) (0%-100% relative humidity at 30°C) at air temperatures between 44° and 56°C. In sociable weavers, a species that dissipates heat primarily through panting, rates of evaporative water loss were inhibited by as much as 36% by high humidity at 48°C, and these birds showed a high degree of hyperthermia. At lower temperatures (40°-44°C), evaporative water loss was largely unaffected by humidity in this species. In Namaqua doves, which primarily use cutaneous evaporation, increasing humidity reduced rates of evaporative water loss, but overall rates of water loss were lower than those observed in sociable weavers. Our data suggest that cutaneous evaporation is more efficient than panting, requiring less water to maintain Tb at a given temperature, but panting appears less sensitive to humidity over the air temperature range investigated here.

  16. Charge collection efficiency in ionization chambers exposed to electron beams with high dose per pulse.

    PubMed

    Laitano, R F; Guerra, A S; Pimpinella, M; Caporali, C; Petrucci, A

    2006-12-21

    The correction for charge recombination was determined for different plane-parallel ionization chambers exposed to clinical electron beams with low and high dose per pulse, respectively. The electron energy was nearly the same (about 7 and 9 MeV) for any of the beams used. Boag's two-voltage analysis (TVA) was used to determine the correction for ion losses, k(s), relevant to each chamber considered. The presence of free electrons in the air of the chamber cavity was accounted for in determining k(s) by TVA. The determination of k(s) was made on the basis of the models for ion recombination proposed in past years by Boag, Hochhäuser and Balk to account for the presence of free electrons. The absorbed dose measurements in both low-dose-per-pulse (less than 0.3 mGy per pulse) and high-dose-per-pulse (20-120 mGy per pulse range) electron beams were compared with ferrous sulphate chemical dosimetry, a method independent of the dose per pulse. The results of the comparison support the conclusion that one of the models is more adequate to correct for ion recombination, even in high-dose-per-pulse conditions, provided that the fraction of free electrons is properly assessed. In this respect the drift velocity and the time constant for attachment of electrons in the air of the chamber cavity are rather critical parameters because of their dependence on chamber dimensions and operational conditions. Finally, a determination of the factor k(s) was also made by zero extrapolation of the 1/Q versus 1/V saturation curves, leading to the conclusion that this method does not provide consistent results in high-dose-per-pulse beams. PMID:17148826

  17. Below Regulatory Concern Owners Group: Doses to the maximally exposed individual from NRC-licensed activities: Final report

    SciTech Connect

    Waite, D.A.; Dolan, M.M.; Mantooth, D.S.

    1989-07-01

    This report estimates the additional radiation dose potentially received by the maximally exposed individual (MEI) from the disposal of Below Regulatory Concern (BRC) waste from other NRC-licensed activities potentially resulting in exposures to members of the general public. The MEI for BRC waste disposal has been identified as the driver of the disposal truck containing BRC waste. The additional doses received by the BRC waste truck driver are determined by identifying the following: (1) the MEI from NRC-licensed activities that result in exposures to the general public (documented in the literature); and (2) the likelihood that the truck driver is also the MEI for those activities. The likelihood that the truck driver is also the MEI from other activities is evaluated based on the time of the potential exposure, its geographic proximity to the BRC waste MEI, and the critical exposure pathway. 3 refs., 1 tab.

  18. Cytoprotective responses in HaCaT keratinocytes exposed to high doses of curcumin.

    PubMed

    Lundvig, Ditte M S; Pennings, Sebastiaan W C; Brouwer, Katrien M; Mtaya-Mlangwa, Matilda; Mugonzibwa, Emeria; Kuijpers-Jagtman, Anne Marie; Wagener, Frank A D T G; Von den Hoff, Johannes W

    2015-08-15

    Wound healing is a complex process that involves the well-coordinated interactions of different cell types. Topical application of high doses of curcumin, a plant-derived polyphenol, enhances both normal and diabetic cutaneous wound healing in rodents. For optimal tissue repair interactions between epidermal keratinocytes and dermal fibroblasts are essential. We previously demonstrated that curcumin increased reactive oxygen species (ROS) formation and apoptosis in dermal fibroblasts, which could be prevented by pre-induction of the cytoprotective enzyme heme oxygenase (HO)-1. To better understand the effects of curcumin on wound repair, we now assessed the effects of high doses of curcumin on the survival of HaCaT keratinocytes and the role of the HO system. We exposed HaCaT keratinocytes to curcumin in the presence or absence of the HO-1 inducers heme (FePP) and cobalt protoporphyrin (CoPP). We then assessed cell survival, ROS formation, and caspase activation. Curcumin induced caspase-dependent apoptosis in HaCaT keratinocytes via a ROS-dependent mechanism. Both FePP and CoPP induced HO-1 expression, but only FePP protected against curcumin-induced ROS formation and caspase-mediated apoptosis. In the presence of curcumin, FePP but not CoPP induced the expression of the iron scavenger ferritin. Together, our data show that the induction of ferritin, but not HO, protects HaCaT keratinocytes against cytotoxic doses of curcumin. The differential response of fibroblasts and keratinocytes to high curcumin doses may provide the basis for improving curcumin-based wound healing therapies. PMID:26071936

  19. New strategies for exploring RNA's 2'-OH expose the importance of solvent during group II intron catalysis.

    PubMed

    Gordon, Peter M; Fong, Robert; Deb, Shirshendu K; Li, Nan-Sheng; Schwans, Jason P; Ye, Jing-Dong; Piccirilli, Joseph A

    2004-02-01

    The 2'-hydroxyl group contributes inextricably to the functional behavior of many RNA molecules, fulfilling numerous essential chemical roles. To assess how hydroxyl groups impart functional behavior to RNA, we developed a series of experimental strategies using an array of nucleoside analogs. These strategies provide the means to investigate whether a hydroxyl group influences function directly (via hydrogen bonding or metal ion coordination), indirectly (via space-filling capacity, inductive effects, and sugar conformation), or through interactions with solvent. The nucleoside analogs span a broad range of chemical diversity, such that quantitative structure activity relationships (QSAR) now become possible in the exploration of RNA biology. We employed these strategies to investigate the spliced exons reopening (SER) reaction of the group II intron. Our results suggest that the cleavage site 2'-hydroxyl may mediate an interaction with a water molecule.

  20. Focused study on the quiet side effect in dwellings highly exposed to road traffic noise.

    PubMed

    Van Renterghem, Timothy; Botteldooren, Dick

    2012-12-01

    This study provides additional evidence for the positive effect of the presence of a quiet façade at a dwelling and aims at unraveling potential mechanisms. Locations with dominant road traffic noise and high L(den)-levels at the most exposed façade were selected. Dwellings both with and without a quiet façade were deliberately sought out. Face-to-face questionnaires (N = 100) were taken to study the influence of the presence of a quiet side in relation to noise annoyance and sleep disturbance. As a direct effect, the absence of a quiet façade in the dwelling (approached as a front-back façade noise level difference smaller than 10 dBA) leads to an important increase of at least moderately annoyed people (odds-ratio adjusted for noise sensitivity equals 3.3). In an indirect way, a bedroom located at the quiet side leads to an even stronger reduction of the self-reported noise annoyance (odds-ratio equal to 10.6 when adjusted for noise sensitivity and front façade L(den)). The quiet side effect seems to be especially applicable for noise sensitive persons. A bedroom located at the quiet side also reduces noise-induced sleep disturbances. On a loud side, bedroom windows are more often closed, however, conflicting with the preference of dwellers.

  1. Viability of Rhodococcus equi and Parascaris equorum eggs exposed to high temperatures.

    PubMed

    Hébert, Laurent; Cauchard, Julien; Doligez, Pauline; Quitard, Lola; Laugier, Claire; Petry, Sandrine

    2010-01-01

    There is great concern about the potential pathogen contamination of horse manure compost spread in the same fields horses graze in. To ensure that pathogen destruction occurs, temperatures need to be sufficiently high during composting. Here, we investigated the survival rate of two marker organisms, Rhodococcus equi and Parascaris equorum eggs, exposed to temperatures potentially encountered during horse manure composting. Our results show that the time required to achieve a 1 log10 reduction in R. equi population (D-value) are 17.1 h (+/-1.47) at 45 degrees C, 8.6 h (+/-0.28) at 50 degrees C, 2.9 h (+/-0.04) at 55 degrees C and 0.7 h (+/-0.04) at 60 degrees C. For P. equorum eggs we show that at 45 and 50 degrees C, 2 log10 reduction of viability is reached between 8 and 24 h of incubation and that it takes less than 2 h at 55 and 60 degrees C to achieve a viability reduction of 2 log10. These results are useful for identifying composting conditions that will reduce the risk of environmental contamination by R. equi and P. equorum eggs.

  2. Ultrastructure of pea and cress root statocytes exposed to high gradient magnetic field

    NASA Astrophysics Data System (ADS)

    Belyavskaya, N. A.; Chernishov, V. I.; Polishchuk, O. V.; Kondrachuk, A. V.

    As it was demonstrated by Kuznetsov & Hasenstein (1996) the high gradient magnetic field (HGMF) can produce a ponderomotive force that results in displacements of amyloplasts and causes the root response similar to the graviresponse. It was suggested that the HGMF could allow to imitate the effects of gravity in microgravity and/or change them in laboratory conditions correspondingly, as well as to study statolith-related processes in graviperception. Therefore, the correlation between the direction of the ponderomotive force resulting in statolith displacements and the direction of the HGMF-induced plant curvature can be the serious argument to support this suggestion and needs the detailed ultrastructural analysis. Seeds of dicotyledon Pisum sativum L. cv. Damir-2 and monocotyledon Lepidium sativum L. cv. P896 were soaked and grown in a vertical position on moist filter paper in chambers at room temperature. Tips of primary roots of vertical control, gravistimulated and exposed to HGMF seedlings were fixed for electron microscopy using conventional techniques. At ultrastructural level, we observed no significant changes in the volume of the individual statocytes or amyloplasts, relative volumes of cellular organelles (except vacuoles), number of amyloplasts per statocyte or surface area of endoplasmic reticulum. No consistent contacts between amyloplasts and any cellular structures, including plasma membrane, were revealed at any stage of magneto- and gravistimulation. By 5 min after onset of magnetostimulation, amyloplasts were located along cell wall distant from magnets. In HGMF, the locations of amyloplasts in columella cells were similar to those in horizontally-oriented roots up to 1 h stimulation. In the latter case, there were sometimes cytoplasmic spherical bodies with a dense vesicle-rich cytoplasm in pea statocytes, which were absent in seedlings exposed to HGMF. In cress root statocytes, both gravi- and magnetostimulation were found to cause the

  3. 3-(3,4-Dihydroxyphenyl)adenine, a urinary DNA adduct formed in mice exposed to high concentrations of benzene.

    PubMed

    Mikeš, Petr; Sístek, Václav; Krouželka, Jan; Králík, Antonín; Frantík, Emil; Mráz, Jaroslav; Linhart, Igor

    2013-06-01

    Metabolism of benzene, an important environmental and industrial carcinogen, produces three electrophilic intermediates, namely, benzene oxide and 1,2- and 1,4-benzoquinone, capable of reacting with the DNA. Numerous DNA adducts formed by these metabolites in vitro have been reported in the literature, but only one of them was hitherto identified in vivo. In a search for urinary DNA adducts, specific LC-ESI-MS methods have been developed for the determination in urine of six nucleobase adducts, namely, 7-phenylguanine, 3-phenyladenine, 3-hydroxy-3,N(4) -benzethenocytosine, N(2) -(4-hydroxyphenyl)guanine, 7-(3,4-dihydroxyphenyl)guanine and 3-(3,4-dihydroxyphenyl)-adenine (DHPA), with detection limits of 200, 10, 260, 50, 400 and 200 pg ml(-1) , respectively. Mice were exposed to benzene vapors at concentrations of 900 and 1800 mg m(-3) , 6 h per day for 15 consecutive days. The only adduct detected in their urine was DHPA. It was found in eight out of 30 urine samples from the high-exposure group at concentrations of 352 ± 146 pg ml(-1) (mean ± SD; n = 8), whereas urines from the low-exposure group were negative. Assuming the DHPA concentration in the negative samples to be half of the detection limit, conversion of benzene to DHPA was estimated to 2.2 × 10(-6) % of the absorbed dose. Thus, despite the known high mutagenic and carcinogenic potential of benzene, only traces of a single DNA adduct in urine were detected. In conclusion, DHPA is an easily depurinating adduct, thus allowing indication of only high recent exposure to benzene, but not long-term damage to DNA in tissues.

  4. ANTIOXIDANT SUPPLEMENTATION AND NASAL INFLAMMATORY RESPONSES AMONG YOUNG ASTHMATICS EXPOSED TO HIGH LEVELS OF OZONE

    EPA Science Inventory

    Background: Recent studies examining the inflammatory response in atopic asthma to ozone suggest a release of soluble mediators of inflammation factors that might be related to reactive oxygen species (ROS). Antioxidant could prove useful in subjects exposed to additional oxidati...

  5. Bulk retention of deuterium in graphites exposed to deuterium plasma at high temperature

    NASA Astrophysics Data System (ADS)

    Arkhipov, I. I.; Gorodetsky, A. E.; Zakharov, A. P.; Khripunov, B. I.; Shapkin, V. V.; Petrov, V. B.; Pistunovich, V. I.; Negodaev, M. A.; Bagulya, A. V.

    1996-10-01

    A highly ionized deuterium plasma with a low residual gas pressure and a high intensity D 2+-ion beam were used for the study of deuterium retention in RG-Ti-91 and POCO AXF-5Q graphites. Deuterium retention in the samples was estimated by TDS during heating to 2000 K. Mechanical removal of a surface layer 100 μm thick was used to distinguish bulk and surface fractions of retained deuterium. The samples of RG-Ti and POCO graphites were exposed to a plasma with an ion flux of 3 × 10 17 D/cm 2 · s in the 'Lenta' plasma device for 10 to 10 4 s at residual deuterium pressure of 0.04 Pa at 1400 K. Under plasma exposure deuterium capture in RG-Ti graphite reached the saturation level at a fluence of 4 × 10 20 D/cm 2 while the bulk inventory was negligible. As for POCO graphite, deuterium retention increased with fluence and was equal to 18 appm in the bulk for a fluence of 7 × 10 21 D/cm 2. The same amount of deuterium in the bulk was obtained after gas exposure of POCO at an effective pressure of 0.8 Pa (1400 K, 6 h). With this result, the tritium concentration in the plasma-facing graphite materials can reach 1500 appm or 380 grams of tritium per ton of graphite. To understand the role of ion flux in generation of effective pressure, POCO was irradiated with 16 keV D 2+-ions at 1400 K for 4 h to 8 × 10 20 D/cm 2 (ion flux was 6 × 10 16 D/cm 2 · s, residual deuterium pressure was 0.004 Pa). The results are discussed on the basis of structural differences for POCO and RG-Ti graphites.

  6. Nitrogen retention in contrasting temperate forests exposed to high nitrogen deposition

    NASA Astrophysics Data System (ADS)

    Staelens, J.; Adriaenssens, S.; Wuyts, K.; Verheyen, K.; Boeckx, P. F.

    2011-12-01

    A better understanding of factors affecting nitrogen (N) retention is needed to assess the impact of changing anthropogenic N emissions and climatic conditions on N cycling and N loss by terrestrial ecosystems. Retention of N has been demonstrated for a wide range of forests, including ecosystems exposed to chronically enhanced N deposition, but it is still unclear which factors determine this N retention capacity. Therefore, we examined the possible effects of forest type on N retention using stable N isotopes. The study was carried out in adjacent equal-aged deciduous (pedunculate oak (Quercus robur L.)) and coniferous (Scots pine (Pinus sylvestris L.)) stands with a similar stand history and growing on a well-drained sandy soil in a region with enhanced N deposition (Belgium). The N input-output budgets and gross soil N transformation rates differed significantly between the two stands. The forest floor was exposed to a high inorganic N input from atmospheric deposition, which was nearly twice as high in the pine stand (33 ± 2 kg N ha-1 yr-1; mean ± standard error) as in the oak stand (18 ± 1 kg N ha-1 yr-1). The N input was reflected in the soil solution under the rooting zone, but the mean nitrate concentration was eight times higher under pine (19 ± 5 mg N L-1) than under oak (2.3 ± 0.9 mg N L-1). Gross N dynamics in the mineral topsoil were determined by in situ 15N labelling of undisturbed soil cores combined with numerical data analysis. Gross N mineralization was two times faster in the oak soil while nitrate production was two times faster in the pine soil, indicating a dominant effect of vegetation cover on soil N cycling. The higher gross nitrification, particularly due to oxidation of organic N, in the pine soil compared to the oak soil, combined with negligible nitrate immobilization, was in line with the higher nitrate leaching under the pine forest. On a larger spatial and temporal scale, the fate of dissolved inorganic N within these forests

  7. Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

    NASA Technical Reports Server (NTRS)

    Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

    2011-01-01

    Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT

  8. The Making of a Cowboy: A High School Group Phenomenon.

    ERIC Educational Resources Information Center

    Serrano, Rodolfo G.

    A study focusing on the development and maintenance of peer groups was undertaken at South High School in the San Joaquin Valley (California). The central purpose of the study was to determine if a school culture existed at this school. Ethnographic and field observation methods were employed to examine the phenomenon of the "cowboys," a group of…

  9. Deuterium retention in codeposited layers and carbon materials exposed to high flux D-plasma

    NASA Astrophysics Data System (ADS)

    Arkhipov, I. I.; Gorodetsky, A. E.; Zalavutdinov, R. Kh; Zakharov, A. P.; Burtseva, T. A.; Mazul, I. V.; Khripunov, B. I.; Shapkin, V. V.; Petrov, V. B.

    A ceramic BCN target with samples of dense RG-Ti-91 without boron, RG-Ti-B with boron (0.1 at.%) and porous POCO AXF-5Q graphites was exposed in a stationary D-plasma of the `Lenta' device with an ion energy of 200 eV and an ion flux of (3 - 6) × 10 17 D/cm 2s at 1040 and 1400 K to a fluence of ˜1 × 10 22 D/cm 2. Codeposited layers were obtained for comparison on the target surface. Thermal desorption spectroscopy (TDS) showed that the amount of deuterium in RG-Ti after exposure at 1040 K was more than an order of magnitude higher than in POCO (9 × 10 17 and 7 × 10 16 D/cm 2, respectively). The retention took place preferentially in a surface layer about 100 μm thick. The bulk deuterium concentration in both RG-Ti and POCO was lower than 1 appm. The irradiated RG-Ti surface was subjected to strong erosion and consisted of `columnar' grains covered with TiC at their tips. The deuterium in RG-Ti irradiated at 1400 K was located in the surface layer (1.5 × 10 16 D/cm 2). The value of the bulk concentration did not exceed 0.1 appm while in POCO it was equal to about 20 appm. TDS for deuterium in RG-Ti demonstrated a spectrum similar to that for codeposited layers on a target surface. The differences in deuterium retention in the graphites are explained on the basis of structural differences. Considering tritium inventory assessment for ITER, dense graphites like RG-Ti are preferred for working divertor plates at high temperatures.

  10. Phenotypic Modifications in Staphylococcus aureus Cells Exposed to High Concentrations of Vancomycin and Teicoplanin

    PubMed Central

    Gonçalves, Fábio D. A.; de Carvalho, Carla C. C. R.

    2016-01-01

    Bacterial cells are known to change the fatty acid (FA) composition of the phospholipids as a phenotypic response to environmental conditions and to the presence of toxic compounds such as antibiotics. In the present study, Staphylococcus aureus cells collected during the exponential growth phase were challenged with 50 and 100 mg/L of vancomycin and teicoplanin, which are concentrations high enough to kill the large majority of the cell population. Colony-forming unit counts showed biphasic killing kinetics, typical for persister cell enrichment, in both antibiotics and concentrations tested. However, fluorescence microscopy showed the existence of viable but non-culturable (VBNC) cells in a larger number than that of possible persister cells. The analysis of the FA composition of the cells showed that, following antibiotic exposure up to 6 h, the survivor cells have an increased percentage of saturated FAs, a significant reduced percentage of branched FAs and an increased iso/anteiso branched FA ratio when compared to cells exhibiting a regular phenotype. This should result in lower membrane fluidity. However, cells exposed for 8–24 h presented an increased branched/saturated and lower iso/anteiso branched FA ratios, and thus increased membrane fluidity. Furthermore, the phenotypic changes were transmitted to daughter cells grown in drug-free media. The fact that VBNC cells presented nearly the same FA composition as those obtained after cell growth in drug-free media, which could only be the result of growth of persister cells, suggest that VBNC and persister phenotypes share the same type of response to antibiotics at the lipid level. PMID:26834731

  11. Early and delayed reproductive death in human cells exposed to high energy iron-ion beams

    NASA Astrophysics Data System (ADS)

    Bettega, D.; Calzolari, P.; Doneda, L.; Durante, M.; Tallone, L.

    For radiation protection of the astronauts it is important to know both the acute and the late effects of charged particles. Iron is the most abundant high charge and energy (HZE) specie in galactic cosmic radiation. (HZE) ions are considered to be the major contributors to equivalent dose in space, but the Relative Biological Effectiveness of HZE particles has large uncertainties, expecially for late effects. We have determined early and delayed reproductive death in human fibroblast cells (AG1522) exposed to iron ion beams of energies between 0.2 and 1 GeV/n. The cells were irradiated at the HIMAC accelerator in Chiba (0.2 and 0.5 GeV/n) and at the AGS accelerator at the NASA Space Radiation Laboratory in Brookhaven (1 GeV/n). For each beam the dose--effect curves were measured at least twice in the dose range between 0.5 and 2 Gy. 60 Co gamma rays were used as reference radiation. The following results were obtained: 1) the 1 GeV/n beam effectiveness for inactivation of the AG1522 cells is higher than that of any other beam. 2) the progeny of the irradiated cells show the presence of delayed damage in the form of reproductive death for all the beams with the 1 GeV/n being the most effective. 3) the relative biological effectiveness of the iron beams is higher for delayed compared to early reproductive death. A comparison with preliminary results obtained with 970 MeV/n Ti and 490 MeV/n Si ions will be also reported .

  12. Spatial Cognition in Adult and Aged Mice Exposed to High-Fat Diet.

    PubMed

    Kesby, James P; Kim, Jane J; Scadeng, Miriam; Woods, Gina; Kado, Deborah M; Olefsky, Jerrold M; Jeste, Dilip V; Achim, Cristian L; Semenova, Svetlana

    2015-01-01

    Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD) exposure, that produce a diabetic phenotype and metabolic dysfunction may indirectly lead to exacerbated brain aging and promote the development of cognitive deficits. The present work investigated whether exposure to HFD exacerbates age-related cognitive deficits in adult versus aged mice. Adult (5 months old) and aged (15 months old) mice were exposed to control diet or HFD for three months prior to, and throughout, behavioral testing. Anxiety-like behavior in the light-dark box test, discrimination learning and memory in the novel object/place recognition tests, and spatial learning and memory in the Barnes maze test were assessed. HFD resulted in significant gains in body weight and fat mass content with adult mice gaining significantly more weight and adipose tissue due to HFD than aged mice. Weight gain was attributed to food calories sourced from fat, but not total calorie intake. HFD increased fasting insulin levels in all mice, but adult mice showed a greater increase relative to aged mice. Behaviorally, HFD increased anxiety-like behavior in adult but not aged mice without significantly affecting spatial cognition. In contrast, aged mice fed either control or HFD diet displayed deficits in novel place discrimination and spatial learning. Our results suggest that adult mice are more susceptible to the physiological and anxiety-like effects of HFD consumption than aged mice, while aged mice displayed deficits in spatial cognition regardless of dietary influence. We conclude that although HFD induces systemic metabolic dysfunction in both adult and aged mice, overall cognitive function was not adversely affected under the current experimental conditions.

  13. Phenotypic Modifications in Staphylococcus aureus Cells Exposed to High Concentrations of Vancomycin and Teicoplanin.

    PubMed

    Gonçalves, Fábio D A; de Carvalho, Carla C C R

    2016-01-01

    Bacterial cells are known to change the fatty acid (FA) composition of the phospholipids as a phenotypic response to environmental conditions and to the presence of toxic compounds such as antibiotics. In the present study, Staphylococcus aureus cells collected during the exponential growth phase were challenged with 50 and 100 mg/L of vancomycin and teicoplanin, which are concentrations high enough to kill the large majority of the cell population. Colony-forming unit counts showed biphasic killing kinetics, typical for persister cell enrichment, in both antibiotics and concentrations tested. However, fluorescence microscopy showed the existence of viable but non-culturable (VBNC) cells in a larger number than that of possible persister cells. The analysis of the FA composition of the cells showed that, following antibiotic exposure up to 6 h, the survivor cells have an increased percentage of saturated FAs, a significant reduced percentage of branched FAs and an increased iso/anteiso branched FA ratio when compared to cells exhibiting a regular phenotype. This should result in lower membrane fluidity. However, cells exposed for 8-24 h presented an increased branched/saturated and lower iso/anteiso branched FA ratios, and thus increased membrane fluidity. Furthermore, the phenotypic changes were transmitted to daughter cells grown in drug-free media. The fact that VBNC cells presented nearly the same FA composition as those obtained after cell growth in drug-free media, which could only be the result of growth of persister cells, suggest that VBNC and persister phenotypes share the same type of response to antibiotics at the lipid level. PMID:26834731

  14. Spatial Cognition in Adult and Aged Mice Exposed to High-Fat Diet.

    PubMed

    Kesby, James P; Kim, Jane J; Scadeng, Miriam; Woods, Gina; Kado, Deborah M; Olefsky, Jerrold M; Jeste, Dilip V; Achim, Cristian L; Semenova, Svetlana

    2015-01-01

    Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD) exposure, that produce a diabetic phenotype and metabolic dysfunction may indirectly lead to exacerbated brain aging and promote the development of cognitive deficits. The present work investigated whether exposure to HFD exacerbates age-related cognitive deficits in adult versus aged mice. Adult (5 months old) and aged (15 months old) mice were exposed to control diet or HFD for three months prior to, and throughout, behavioral testing. Anxiety-like behavior in the light-dark box test, discrimination learning and memory in the novel object/place recognition tests, and spatial learning and memory in the Barnes maze test were assessed. HFD resulted in significant gains in body weight and fat mass content with adult mice gaining significantly more weight and adipose tissue due to HFD than aged mice. Weight gain was attributed to food calories sourced from fat, but not total calorie intake. HFD increased fasting insulin levels in all mice, but adult mice showed a greater increase relative to aged mice. Behaviorally, HFD increased anxiety-like behavior in adult but not aged mice without significantly affecting spatial cognition. In contrast, aged mice fed either control or HFD diet displayed deficits in novel place discrimination and spatial learning. Our results suggest that adult mice are more susceptible to the physiological and anxiety-like effects of HFD consumption than aged mice, while aged mice displayed deficits in spatial cognition regardless of dietary influence. We conclude that although HFD induces systemic metabolic dysfunction in both adult and aged mice, overall cognitive function was not adversely affected under the current experimental conditions. PMID:26448649

  15. Indoor tanning and risk of melanoma: a case-control study in a highly exposed population

    PubMed Central

    Lazovich, DeAnn; Vogel, Rachel Isaksson; Berwick, Marianne; Weinstock, Martin A.; Anderson, Kristin E.; Warshaw, Erin M.

    2010-01-01

    Background Indoor tanning has been only weakly associated with melanoma risk; most reports were unable to adjust for sun exposure, confirm a dose-response, or examine specific tanning devices. A population-based case-control study was conducted to address these limitations. Methods Cases of invasive cutaneous melanoma, diagnosed in Minnesota between 2004-2007 at ages 25-59, were ascertained from a statewide cancer registry; age-, gender-matched controls were randomly selected from state driver's license lists. Self-administered questionnaires and telephone interviews included information on ever use of indoor tanning, device types used, initiation age, period of use, dose, duration, and indoor-tanning related burns. Odds ratios (OR) and 95% confidence intervals (CI) were adjusted for known melanoma risk factors. Results Among 1167 cases and 1101 controls, 62.9% of cases and 51.1% of controls had tanned indoors (adjusted OR 1.74, 95% CI 1.42-2.14). Melanoma risk was pronounced among users of UVB-enhanced (adjusted OR 2.86, 95% CI 2.03-4.03) and primarily UVA-emitting devices (adjusted OR 4.44, 95% CI 2.45, 8.02). Risk increased with use: years (p<0.006), hours (p<0.0001), or sessions (p=0.0002). Odds ratios were elevated within each initiation age category; among indoor tanners, years used was more relevant for melanoma development. Conclusions In a highly exposed population, frequent indoor tanning increased melanoma risk, regardless of age when indoor tanning began. Elevated risks were observed across devices. Impact This study overcomes some of the limitations of earlier reports and provides strong support for the recent declaration by International Agency for Research on Cancer that tanning devices are carcinogenic in humans. PMID:20507845

  16. Comparative toxicity and micronuclei formation in Tribolium castaneum, Callosobruchus maculatus and Sitophilus oryzae exposed to high doses of gamma radiation.

    PubMed

    Ahmadi, Mehrdad; Mozdarani, Hossein; Abd-Alla, Adly M M

    2015-07-01

    The effects of gamma radiation on mortality and micronucleus formation in Tribolium castaneum Herbst, Callosobruchus maculatus (F.) and Sitophilus oryzae (L.) genital cells were evaluated. Two groups of healthy and active adult insects 1-3 and 8-10 days old were irradiated with various doses (50-200 Gy) gamma ray. Seven days post-irradiation; mortality rates and micronucleus formation were assessed in genital cells of the irradiated insects. The results show that with increasing gamma doses, the mortality rate of each species increased and T. castaneum and S. oryzae showed the low and high sensitivity respectively. It was shown that the micronucleus appearance in the tested insects had correlation with amount and intensity of radiation doses. Moreover our results indicate different levels in the genotoxicity of gamma radiation among the insects' genital cells under study. The frequency of micronuclei in genital cells of 1-3 days old insects exposed to 50 and 200 Gy were 12.6 and 38.8 Mn/1000 cells in T. castaneum, 20.8 and 46.8 Mn/1000 cells in C. maculatus and 16.8 and 57.2 Mn/1000 cells in S. oryzae respectively. A high sensitivity of the genital cells to irradiation exposure was seen in S. oryzae correlated with its high mortality rate compared with the other two species. These results might be indicative of inflicting chromosomal damage expressed as micronucleus in high mortality rates observed in the pest population; an indication of genotoxic effects of radiation on the studied species.

  17. CRITICAL BODY RESIDUES FOR FRESHWATER AND SALTWATER AMPHIPODS EXPOSED TO SEDIMENT CONTAINING A MIXTURE OF HIGH KOW PAHS

    EPA Science Inventory

    Sediments were spiked with a mixture of 13 high log Kow (5.4-6.8) PAH compounds to determine critical body residues (CBR) in Hyalella azteca and Leptocheirus plumulosus. Hyalella were exposed for 28 d in a intermittent flow test and for 10 d in a static test to compare PAH uptake...

  18. Mental Health Service Use among High School Students Exposed to Interpersonal Violence

    ERIC Educational Resources Information Center

    Green, Jennifer Greif; Johnson, Renee M.; Dunn, Erin C.; Lindsey, Michael; Xuan, Ziming; Zaslavsky, Alan M.

    2014-01-01

    Background: Violence-exposed youth rarely receive mental health services, even though exposure increases risk for academic and psychosocial problems. This study examines the association between violence exposure and mental health service contact. The 4 forms of violence exposure were peer, family, sexual, and witnessing. Methods: Data are from…

  19. Histologic study of the internal organs of rats chronically exposed to a high-intensity electric field

    SciTech Connect

    Seto, Y.J.; Majeau-Chargois, D.; Lymangrover, J.R.; Dunlap, W.P.; Hsieh, S.T.

    1985-01-01

    The effect of 120-day exposure to a high-intensity (80 kV/m), 60-Hz electric field on histology of selected internal organs of Sprague-Dawley rats was investigated. The organs examined were the pituitary, thymus, heart, lungs, liver, spleen, right and left adrenals, right and left kidneys, and right and left testes. Histological examination of 10-micron tissue sections from randomly selected animals revealed no specific evidence of histopathologic differences between field-exposed and sham-exposed animals at the light microscopic level.

  20. Identification of heat shock proteins via transcriptome profiling of tree peony leaf exposed to high temperature.

    PubMed

    Zhang, Y Z; Cheng, Y W; Ya, H Y; Han, J M; Zheng, L

    2015-07-28

    The tree peony leaf is an important vegetative organ that is sensitive to abiotic stress and particularly to high temperature. This sensitivity affects plant growth and restricts tree peony distribution. However, the transcriptomic information currently available on the peony leaf in public databases is limited. In this study, we sequenced the transcriptomes of peony leaves subjected to high temperature using the Illumina HiSeq TM 2000 platform. We performed de novo assembly of 93,714 unigenes (average length of 639.7 bp). By searching the public databases, 22,323 unigenes and 13,107 unigenes showed significant similarities with proteins in the NCBI non-redundant protein database and SWISS-PROT database (E-value < 1e-5), respectively. We assigned 17,340 unigenes to Gene Ontology categories, and we assigned 7618 unigenes to clusters of orthologous groups for eukaryotic complete genomes. By searching the Kyoto Encyclopedia of Genes and Genomes Pathway database, 8014 unigenes were assigned to 6 main categories, including 290 KEGG pathways. To advance research on improving thermotolerance, we identified 24 potential heat shock protein genes with complete open reading frames from the transcriptomic sequences. This is the first study to characterize the leaf transcriptome of tree peony leaf using high-throughput sequencing. The information obtained from the tree peony leaf is valuable for gene discovery, and the identified heat shock protein genes can be used to improve plant stress-tolerance.

  1. Metabolomics in Lung Inflammation: A High Resolution 1H NMR Study of Mice Exposed to Silica Dust

    PubMed Central

    Hu, Jian Zhi; Rommereim, Donald N.; Minard, Kevin R.; Woodstock, Angie; Harrer, Bruce J.; Wind, Robert A.; Phipps, Richard P.; Sime, Patricia J.

    2010-01-01

    Here we report the first 1H NMR metabolomics studies on excised lungs and bronchoalveolar lavage fluid (BALF) from mice exposed to crystalline silica. High resolution 1H NMR metabolic profiling on intact excised lungs was performed using slow magic angle sample spinning (slow-MAS) 1H PASS (phase altered spinning sidebands) at a sample spinning rate of 80 Hz. Metabolic profiling on BALF was completed using fast magic angle spinning at 2kHz. Major findings are that the relative concentrations of choline, phosphocholine (PC) and glycerophosphocholine(GPC) were statistically significantly increased in silica-exposed mice compared to sham controls, indicating an altered membrane choline phospholipids metabolism (MCPM). The relative concentrations of glycogen/glucose, lactate and creatine were also statistically significantly increased in mice exposed to silica dust, suggesting that cellular energy pathways were affected by silica dust. Elevated levels of glycine, lysine, glutamate, proline and 4-hydroxyproline were also increased in exposed mice, suggesting the activation of a collagen pathway. Furthermore, metabolic profiles in mice exposed to silica dust were found to be spatially heterogeneous, in consistent with regional inflammation revealed by in vivo magnetic resonance imaging (MRI). PMID:20020862

  2. The quantification of wound healing as a method to assess late radiation damage in primate skin exposed to high-energy protons

    NASA Astrophysics Data System (ADS)

    Cox, A. B.; Lett, J. T.

    In an experiment examining the effects of space radiations on primates, different groups of rhesus monkeys (Macaca mulatta) were exposed to single whole-body doses of 32- or 55-MeV protons. Survivors of those exposures, together with age-matched controls, have been monitored continuously since 1964 and 1965. Late effects of nominal proton doses ranging from 2-6 Gray have been measured in vitro using skin fibroblasts from the animals. A logical extension of that study is reported here, and it involves observations of wound healing after 3-mm diameter dermal punches were removed from the ears (pinnae) of control and irradiated monkeys. Tendencies in the reduction of competence to repair cutaneous wound have been revealed by the initial examinations of animals that received doses greater than 2 Gy more than 2 decades earlier. These trends indicate that this method of assessing radiation damage to skin exposed to high-energy radiations warrants further study.

  3. Occurrence of trivalent monomethyl arsenic and other urinary arsenic species in a highly exposed juvenile population in Bangladesh.

    PubMed

    Kalman, David A; Dills, Russell L; Steinmaus, Craig; Yunus, Md; Khan, Al Fazal; Prodhan, Md Mofijuddin; Yuan, Yan; Smith, Allan H

    2014-01-01

    Following reports of high cytotoxicity and mutagenicity of monomethyl arsonous acid (MMA(III)) and early reports of urinary MMA(III) in arsenic-exposed individuals, MMA(III) has often been included in population studies. Use of urinary MMA(III) as an indicator of exposure and/or health risk is challenged by inconsistent results from field studies and stability studies, which indicate potential artifacts. We measured urinary arsenic species in children chronically exposed to arsenic in drinking water, using collection, storage, and analysis methods shown to conserve MMA(III). MMA(III) was easily oxidized in sample storage and processing, but recoveries of 80% or better in spiked urine samples were achieved. Attempts to preserve the distribution of MMA between trivalent and pentavalent forms using complexing agents were unsuccessful and MMA(III) spiked into treated urine samples actually showed lower stability than in untreated samples. In 643 urine samples from a highly exposed population from the Matlab district in Bangladesh stored for 3-6 months at ≤-70 °C, MMA(III) was detected in 41 samples, with an estimated median value of 0.3 μg/l, and levels of MMA(III) above 1 μg/l in only two samples. The low urinary concentrations in highly exposed individuals and known difficulties in preserving sample oxidation state indicate that urinary MMA(III) is not suitable for use as an epidemiological biomarker.

  4. Simultaneous realization of high catalytic activity and stability for catalytic cracking of n-heptane on highly exposed (010) crystal planes of nanosheet ZSM-5 zeolite.

    PubMed

    Xiao, Xia; Zhang, Yaoyuan; Jiang, Guiyuan; Liu, Jia; Han, Shanlei; Zhao, Zhen; Wang, Ruipu; Li, Cong; Xu, Chunming; Duan, Aijun; Wang, Yajun; Liu, Jian; Wei, Yuechang

    2016-08-01

    Nanosheet ZSM-5 zeolite with highly exposed (010) crystal planes demonstrates high reactivity and good anti-coking stability for the catalytic cracking of n-heptane, which is attributed to the synergy of high external surface area and acid sites, fully accessible channel intersection acid sites, and hierarchical porosity caused by the unique morphology.

  5. High-performance heterogeneous catalysis with surface-exposed stable metal nanoparticles

    PubMed Central

    Huang, Ning; Xu, Yanhong; Jiang, Donglin

    2014-01-01

    Protection of metal nanoparticles from agglomeration is critical for their functions and applications. The conventional method for enhancing their stability is to cover them with passivation layers to prevent direct contact. However, the presence of a protective shell blocks exposure of the metal species to reactants, thereby significantly impeding the nanoparticles' utility as catalysts. Here, we report that metal nanoparticles can be prepared and used in a surface-exposed state that renders them inherently catalytically active. This strategy is realised by spatial confinement and electronic stabilisation with a dual-module mesoporous and microporous three-dimensional π-network in which surface-exposed nanoparticles are crystallised upon in situ reduction. The uncovered palladium nanoparticles serve as heterogeneous catalysts that are exceptionally active in water, catalyse unreactive aryl chlorides for straightforward carbon–carbon bond formation and are stable for repeated use in various types of cross couplings. Therefore, our results open new perspectives in developing practical heterogeneous catalysts. PMID:25427425

  6. Homology Groups of High-Resolution Temporal Rainfall

    NASA Astrophysics Data System (ADS)

    Vásquez Aguilar, R.; Carsteanu, A. A.

    2015-12-01

    Using high-resolution temporal rainfall intensities from Iowa City, IA (IIHR, U of Iowa), we perform an analysis of the homology groups generated by data connectivity in state space, and attempt a qualitative interpretation of the first and second homology groups. Let us note that homology groups are generated, in the context of topological data analysis (TDA), by representing the data in n-dimensional state space and building a connectivity diagram according to the respective distances between the data points. Subsequently, the topological invariants of the resulting connected structures are being analyzed.

  7. Thermal shock behaviour of H and H/He-exposed tungsten at high temperature

    NASA Astrophysics Data System (ADS)

    Lemahieu, N.; Greuner, H.; Linke, J.; Maier, H.; Pintsuk, G.; Wirtz, M.; Van Oost, G.; Noterdaeme, J.-M.

    2016-02-01

    Polycrystalline tungsten samples were characterized and exposed to a pure H beam or mixed H/He beam containing 6% He in GLADIS at a surface temperature of 600 °C, 1000 °C, or 1500 °C. After 5400 s of exposure time with a heat flux of 10.5 MW m-2, the total accumulated fluence of 2 × 1025 m-2 was reached. Thereafter, edge localized mode (ELM)-like thermal shocks with a duration of 1 ms and an absorbed power density of 190 MW m-2 and 380 MW m-2 were applied on the samples in JUDITH 1. During the thermal shocks, the base temperature was kept at 1000 °C. The ELM-experiments with the lowest transient power density did not result in any detected damage. The other tests showed the beginning of crack formation for every sample, except the sample pre-exposed with the pure H-beam at 1500 °C in GLADIS. This sample was roughened, but did not show any crack initiation. With exception to the roughened sample, the category of ELM-induced damage for the pre-exposed samples is identical to the reference tests without pre-exposure to a particle flux.

  8. High-order social interactions in groups of mice

    PubMed Central

    Shemesh, Yair; Sztainberg, Yehezkel; Forkosh, Oren; Shlapobersky, Tamar; Chen, Alon; Schneidman, Elad

    2013-01-01

    Social behavior in mammals is often studied in pairs under artificial conditions, yet groups may rely on more complicated social structures. Here, we use a novel system for tracking multiple animals in a rich environment to characterize the nature of group behavior and interactions, and show strongly correlated group behavior in mice. We have found that the minimal models that rely only on individual traits and pairwise correlations between animals are not enough to capture group behavior, but that models that include third-order interactions give a very accurate description of the group. These models allow us to infer social interaction maps for individual groups. Using this approach, we show that environmental complexity during adolescence affects the collective group behavior of adult mice, in particular altering the role of high-order structure. Our results provide new experimental and mathematical frameworks for studying group behavior and social interactions. DOI: http://dx.doi.org/10.7554/eLife.00759.001 PMID:24015357

  9. High-throughput transcriptome analysis of barley (Hordeum vulgare) exposed to excessive boron.

    PubMed

    Tombuloglu, Guzin; Tombuloglu, Huseyin; Sakcali, M Serdal; Unver, Turgay

    2015-02-15

    Boron (B) is an essential micronutrient for optimum plant growth. However, above certain threshold B is toxic and causes yield loss in agricultural lands. While a number of studies were conducted to understand B tolerance mechanism, a transcriptome-wide approach for B tolerant barley is performed here for the first time. A high-throughput RNA-Seq (cDNA) sequencing technology (Illumina) was used with barley (Hordeum vulgare), yielding 208 million clean reads. In total, 256,874 unigenes were generated and assigned to known peptide databases: Gene Ontology (GO) (99,043), Swiss-Prot (38,266), Clusters of Orthologous Groups (COG) (26,250), and the Kyoto Encyclopedia of Genes and Genomes (KEGG) (36,860), as determined by BLASTx search. According to the digital gene expression (DGE) analyses, 16% and 17% of the transcripts were found to be differentially regulated in root and leaf tissues, respectively. Most of them were involved in cell wall, stress response, membrane, protein kinase and transporter mechanisms. Some of the genes detected as highly expressed in root tissue are phospholipases, predicted divalent heavy-metal cation transporters, formin-like proteins and calmodulin/Ca(2+)-binding proteins. In addition, chitin-binding lectin precursor, ubiquitin carboxyl-terminal hydrolase, and serine/threonine-protein kinase AFC2 genes were indicated to be highly regulated in leaf tissue upon excess B treatment. Some pathways, such as the Ca(2+)-calmodulin system, are activated in response to B toxicity. The differential regulation of 10 transcripts was confirmed by qRT-PCR, revealing the tissue-specific responses against B toxicity and their putative function in B-tolerance mechanisms.

  10. Trends in annual minimum exposed snow and ice cover in High Mountain Asia from MODIS

    NASA Astrophysics Data System (ADS)

    Rittger, Karl; Brodzik, Mary J.; Painter, Thomas H.; Racoviteanu, Adina; Armstrong, Richard; Dozier, Jeff

    2016-04-01

    Though a relatively short record on climatological scales, data from the Moderate Resolution Imaging Spectroradiometer (MODIS) from 2000-2014 can be used to evaluate changes in the cryosphere and provide a robust baseline for future observations from space. We use the MODIS Snow Covered Area and Grain size (MODSCAG) algorithm, based on spectral mixture analysis, to estimate daily fractional snow and ice cover and the MODICE Persistent Ice (MODICE) algorithm to estimate the annual minimum snow and ice fraction (fSCA) for each year from 2000 to 2014 in High Mountain Asia. We have found that MODSCAG performs better than other algorithms, such as the Normalized Difference Index (NDSI), at detecting snow. We use MODICE because it minimizes false positives (compared to maximum extents), for example, when bright soils or clouds are incorrectly classified as snow, a common problem with optical satellite snow mapping. We analyze changes in area using the annual MODICE maps of minimum snow and ice cover for over 15,000 individual glaciers as defined by the Randolph Glacier Inventory (RGI) Version 5, focusing on the Amu Darya, Syr Darya, Upper Indus, Ganges, and Brahmaputra River basins. For each glacier with an area of at least 1 km2 as defined by RGI, we sum the total minimum snow and ice covered area for each year from 2000 to 2014 and estimate the trends in area loss or gain. We find the largest loss in annual minimum snow and ice extent for 2000-2014 in the Brahmaputra and Ganges with 57% and 40%, respectively, of analyzed glaciers with significant losses (p-value<0.05). In the Upper Indus River basin, we see both gains and losses in minimum snow and ice extent, but more glaciers with losses than gains. Our analysis shows that a smaller proportion of glaciers in the Amu Darya and Syr Darya are experiencing significant changes in minimum snow and ice extent (3.5% and 12.2%), possibly because more of the glaciers in this region are smaller than 1 km2 than in the Indus

  11. High risk groups in an oil shale workforce

    SciTech Connect

    Gratt, L.B.; Marine, W.M.; Perry, B.W.; Savitz, D.A.

    1984-04-01

    The workforce risks of a hypothetical one million barrels-per-day oil shale industry were estimated. The risks for the different workforce segments were compared and high risk groups were identified. Accidents and injuries were statistically described by rates for fatalities, for accidents with days lost from work, and for accidents with no days lost from work. Workforce diseases analyzed were cancers, silicosis, pneumoconiosis, chronic bronchitis, chronic airway obstruction, and high frequency hearing loss. A comparison of the workforce groups under different risk measures (occurrence, fatality, and life-loss expectancy) was performed. The miners represented the group with the largest fatality and the most serious accident rate, although the estimated rates were below the average industry-wide underground mining experience. Lung disease from inhalation exposure of about the nuisance dust threshold limit value presents a significant risk for future concerns.

  12. A layered mixed zirconium phosphate/phosphonate with exposed carboxylic and phosphonic groups: X-ray powder structure and proton conductivity properties.

    PubMed

    Donnadio, Anna; Nocchetti, Morena; Costantino, Ferdinando; Taddei, Marco; Casciola, Mario; da Silva Lisboa, Fábio; Vivani, Riccardo

    2014-12-15

    A novel mixed zirconium phosphate/phosphonate based on glyphosine, of formula Zr2(PO4)H5(L)2·H2O [L = (O3PCH2)2NCH2COO], was synthesized in mild conditions. The compound has a layered structure that was solved ab initio from laboratory PXRD data. It crystallizes in the monoclinic C2/c space group with the following cell parameters: a = 29.925(3), b = 8.4225(5), c = 9.0985(4) Å, and β = 98.474(6)°. Phosphate groups are placed inside the sheets and connect the zirconium atoms in a tetradentate fashion, while uncoordinated carboxylate and P-OH phosphonate groups are exposed on the layer surface. Due to the presence of these acidic groups, the compound showed remarkable proton conductivity properties, which were studied in a wide range of temperature and relative humidity (RH). The conductivity is strongly dependent on RH and reaches 1 × 10(-3) S cm(-1) at 140 °C and 95% RH. At this RH, the activation energy of conduction is 0.15 eV in the temperature range 80-140 °C. The similarities of this structure with related structures already reported in the literature were also discussed.

  13. Social aspects of high-risk notification among chromium-exposed workers.

    PubMed

    Needleman, C

    1993-01-01

    This study, based on 169 telephone interviews, explores how a sample of chromium-exposed workers responded to notification of their cohort's elevated risk of lung cancer. It is important to recognize that notified workers do not react as isolated individuals. Their responses are social, actively constructed through interaction with others, unfolding over time within a context of relationships and shared symbols that mediate the risk information. This report illustrates some of the ways that socially-based beliefs and interaction with the social environment can influence worker response, and suggests a more sociologically sophisticated concept of notification to fit the realities of workers' lives.

  14. Designing High Quality Research in Special Education: Group Experimental Designs.

    ERIC Educational Resources Information Center

    Gersten, Russell; Lloyd, John Wills; Baker, Scott

    This paper, a result of a series of meetings of researchers, discusses critical issues related to the conduct of high-quality intervention research in special education using experimental and quasi-experimental designs that compare outcomes for different groups of students. It stresses the need to balance design components that satisfy laboratory…

  15. Association between TLR3 rs3775291 and resistance to HIV among highly exposed Caucasian intravenous drug users

    PubMed Central

    Huik, Kristi; Avi, Radko; Pauskar, Merit; Kallas, Eveli; Jõgeda, Ene-Ly; Karki, Tõnis; Marsh, Kristina; Jarlais, Don Des; Uusküla, Anneli; Lutsar, Irja

    2014-01-01

    Background TLR3 recognizes dsRNA and triggers immune responses against RNA and DNA viruses. A polymorphism in TLR3, rs3775291 (Leu412Phe), has been associated with the increased susceptibility to enteroviral myocarditis, protection against tick-borne encephalitis virus and HIV-1 infection. We investigated Caucasian intravenous drug users (IDUs) and blood donors in order to evaluate the associations between TLR3 genotypes and susceptibility to HIV infection. Materials and methods A total of 345 Caucasian IDUs were recruited, 50% of them were HIV positive, 89% HCV and 77% HBV positive. Based on their history of needle sharing, 20 of the HIV negative IDUs were classified as highly exposed HIV seronegatives (HESNs), 68 as non-HESNs and 85 as unexposed. The control group consisting of 497 blood donors tested negative for all three viruses. TLR3 rs3775291 were determined by using TaqMan Allelic Discrimination Assay. Results The TLR3 rs3775291 T allele frequency was similar among the HIV negative and HIV positive IDUs and blood donors – 36%, 31% and 34%, respectively. The frequency of persons possessing at least one TLR3 rs3775291 T allele was significantly higher in HESNs compared with blood donors and HIV positive IDUs (80% vs. 55%; p = 0.037 and 80% vs. 53%; p = 0.031, respectively). In the univariate analysis, persons who possessed at least one T allele had reduced odds of being HIV seropositive (OR = 0.29, 95% CI = 0.09–0.90). This association remained significant (OR = 0.25, 95% CI = 0.07–0.87) after the adjustment for other co-variates (HCV, HBV serostatus and duration of intravenous drug use). Conclusions The TLR3 rs3775291 T allele has a protective effect against HIV infection among HESNs IDUs. PMID:23962581

  16. Effect of high-fat intake on motor activity, homovanillic acid and 5-hydroxyindoleacetic acid levels in striatum and cortex of rats exposed to stress.

    PubMed

    Kirac, Deniz; Ozden, Inci; Yildirim, Alper; Genç, Ece

    2009-04-01

    The aim of the present study was to investigate whether high fat consumption changes the effects of stress on both motor activity performance, striatal and cortical dopamine and serotonin metabolites in rats. The animals were fed either with high fat or standard diet for 4 weeks. Restraint stress lasting for 15 min at +4 degrees C was applied daily to stress-exposed groups. Motor activity performance was measured weekly by using motor activity monitoring systems. At the end of the study, homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) levels of the striatum and cerebral cortex were measured by HPLCEC. It was observed that restraint stress increased locomotor activity and high-fat diet prevented this effect. Stress and high-fat intake had an additive decreasing effect on striatal HVA levels. 5-HIAA levels, on the other hand, were lower in both high fat and high fat + stress groups compared to the stress group. These results suggest that high-fat intake differentially affected the stress response on striatal dopaminergic and serotonergic neurons in rat brain regions studied and this may be related to the effects observed in motor activity performance.

  17. Mice repeatedly exposed to Group-A β-Haemolytic Streptococcus show perseverative behaviors, impaired sensorimotor gating, and immune activation in rostral diencephalon

    PubMed Central

    Macrì, Simone; Ceci, Chiara; Onori, Martina Proietti; Invernizzi, Roberto William; Bartolini, Erika; Altabella, Luisa; Canese, Rossella; Imperi, Monica; Orefici, Graziella; Creti, Roberta; Margarit, Immaculada; Magliozzi, Roberta; Laviola, Giovanni

    2015-01-01

    Repeated exposure to Group-A β-Haemolytic Streptococcus (GAS) may constitute a vulnerability factor in the onset and course of pediatric motor disturbances. GAS infections/colonization can stimulate the production of antibodies, which may cross the blood brain barrier, target selected brain areas (e.g. basal ganglia), and exacerbate motor alterations. Here, we exposed developing SJL male mice to four injections with a GAS homogenate and evaluated the following domains: motor coordination; general locomotion; repetitive behaviors; perseverative responses; and sensorimotor gating (pre-pulse inhibition, PPI). To demonstrate that behavioral changes were associated with immune-mediated brain alterations, we analyzed, in selected brain areas, the presence of infiltrates and microglial activation (immunohistochemistry), monoamines (HPLC), and brain metabolites (in vivo Magnetic Resonance Spectroscopy). GAS-exposed mice showed increased repetitive and perseverative behaviors, impaired PPI, and reduced concentrations of serotonin in prefrontal cortex, a brain area linked to the behavioral domains investigated, wherein they also showed remarkable elevations in lactate. Active inflammatory processes were substantiated by the observation of infiltrates and microglial activation in the white matter of the anterior diencephalon. These data support the hypothesis that repeated GAS exposure may elicit inflammatory responses in brain areas involved in motor control and perseverative behavior, and result in phenotypic abnormalities. PMID:26304458

  18. Mice repeatedly exposed to Group-A β-Haemolytic Streptococcus show perseverative behaviors, impaired sensorimotor gating, and immune activation in rostral diencephalon.

    PubMed

    Macrì, Simone; Ceci, Chiara; Onori, Martina Proietti; Invernizzi, Roberto William; Bartolini, Erika; Altabella, Luisa; Canese, Rossella; Imperi, Monica; Orefici, Graziella; Creti, Roberta; Margarit, Immaculada; Magliozzi, Roberta; Laviola, Giovanni

    2015-08-25

    Repeated exposure to Group-A β-Haemolytic Streptococcus (GAS) may constitute a vulnerability factor in the onset and course of pediatric motor disturbances. GAS infections/colonization can stimulate the production of antibodies, which may cross the blood brain barrier, target selected brain areas (e.g. basal ganglia), and exacerbate motor alterations. Here, we exposed developing SJL male mice to four injections with a GAS homogenate and evaluated the following domains: motor coordination; general locomotion; repetitive behaviors; perseverative responses; and sensorimotor gating (pre-pulse inhibition, PPI). To demonstrate that behavioral changes were associated with immune-mediated brain alterations, we analyzed, in selected brain areas, the presence of infiltrates and microglial activation (immunohistochemistry), monoamines (HPLC), and brain metabolites (in vivo Magnetic Resonance Spectroscopy). GAS-exposed mice showed increased repetitive and perseverative behaviors, impaired PPI, and reduced concentrations of serotonin in prefrontal cortex, a brain area linked to the behavioral domains investigated, wherein they also showed remarkable elevations in lactate. Active inflammatory processes were substantiated by the observation of infiltrates and microglial activation in the white matter of the anterior diencephalon. These data support the hypothesis that repeated GAS exposure may elicit inflammatory responses in brain areas involved in motor control and perseverative behavior, and result in phenotypic abnormalities.

  19. BOOGIE: Predicting Blood Groups from High Throughput Sequencing Data

    PubMed Central

    Giollo, Manuel; Minervini, Giovanni; Scalzotto, Marta; Leonardi, Emanuela; Ferrari, Carlo; Tosatto, Silvio C. E.

    2015-01-01

    Over the last decade, we have witnessed an incredible growth in the amount of available genotype data due to high throughput sequencing (HTS) techniques. This information may be used to predict phenotypes of medical relevance, and pave the way towards personalized medicine. Blood phenotypes (e.g. ABO and Rh) are a purely genetic trait that has been extensively studied for decades, with currently over thirty known blood groups. Given the public availability of blood group data, it is of interest to predict these phenotypes from HTS data which may translate into more accurate blood typing in clinical practice. Here we propose BOOGIE, a fast predictor for the inference of blood groups from single nucleotide variant (SNV) databases. We focus on the prediction of thirty blood groups ranging from the well known ABO and Rh, to the less studied Junior or Diego. BOOGIE correctly predicted the blood group with 94% accuracy for the Personal Genome Project whole genome profiles where good quality SNV annotation was available. Additionally, our tool produces a high quality haplotype phase, which is of interest in the context of ethnicity-specific polymorphisms or traits. The versatility and simplicity of the analysis make it easily interpretable and allow easy extension of the protocol towards other phenotypes. BOOGIE can be downloaded from URL http://protein.bio.unipd.it/download/. PMID:25893845

  20. Mechanisms of blood pressure regulation that differ in men repeatedly exposed to high-G acceleration

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.

    2001-01-01

    The purpose of this study was to test the hypothesis that repeated exposure to high acceleration (G) would be associated with enhanced functions of specific mechanisms of blood pressure regulation. We measured heart rate (HR), stroke volume (SV), cardiac output (), mean arterial blood pressure, central venous pressure, forearm and leg vascular resistance, catecholamines, and changes in leg volume (%DeltaLV) during various protocols of lower body negative pressure (LBNP), carotid stimulation, and infusions of adrenoreceptor agonists in 10 males after three training sessions on different days over a period of 5-7 days using a human centrifuge (G trained). These responses were compared with the same measurements in 10 males who were matched for height, weight, and fitness but did not undergo G training (controls). Compared with the control group, G-trained subjects demonstrated greater R-R interval response to equal carotid baroreceptor stimulation (7.3 +/- 1.2 vs. 3.9 +/- 0.4 ms/mmHg, P = 0.02), less vasoconstriction to equal low-pressure baroreceptor stimulation (-1.4 +/- 0.2 vs. -2.6 +/- 0.3 U/mmHg, P = 0.01), and higher HR (-1.2 +/- 0.2 vs. -0.5 +/- 0.1 beats. min(-1). mmHg(-1), P = 0.01) and alpha-adrenoreceptor response (32.8 +/- 3.4 vs. 19.5 +/- 4.7 U/mmHg, P = 0.04) to equal dose of phenylephrine. During graded LBNP, G-trained subjects had less decline in and SV, %DeltaLV, and elevation in thoracic impedance. G-trained subjects also had greater total blood (6,497 +/- 496 vs. 5,438 +/- 228 ml, P = 0.07) and erythrocyte (3,110 +/- 364 vs. 2,310 +/- 96 ml, P = 0.06) volumes. These results support the hypothesis that exposure to repeated high G is associated with increased capacities of mechanisms that underlie blood pressure regulation.

  1. Mechanisms of blood pressure regulation that differ in men repeatedly exposed to high-G acceleration.

    PubMed

    Convertino, V A

    2001-04-01

    The purpose of this study was to test the hypothesis that repeated exposure to high acceleration (G) would be associated with enhanced functions of specific mechanisms of blood pressure regulation. We measured heart rate (HR), stroke volume (SV), cardiac output (), mean arterial blood pressure, central venous pressure, forearm and leg vascular resistance, catecholamines, and changes in leg volume (%DeltaLV) during various protocols of lower body negative pressure (LBNP), carotid stimulation, and infusions of adrenoreceptor agonists in 10 males after three training sessions on different days over a period of 5-7 days using a human centrifuge (G trained). These responses were compared with the same measurements in 10 males who were matched for height, weight, and fitness but did not undergo G training (controls). Compared with the control group, G-trained subjects demonstrated greater R-R interval response to equal carotid baroreceptor stimulation (7.3 +/- 1.2 vs. 3.9 +/- 0.4 ms/mmHg, P = 0.02), less vasoconstriction to equal low-pressure baroreceptor stimulation (-1.4 +/- 0.2 vs. -2.6 +/- 0.3 U/mmHg, P = 0.01), and higher HR (-1.2 +/- 0.2 vs. -0.5 +/- 0.1 beats. min(-1). mmHg(-1), P = 0.01) and alpha-adrenoreceptor response (32.8 +/- 3.4 vs. 19.5 +/- 4.7 U/mmHg, P = 0.04) to equal dose of phenylephrine. During graded LBNP, G-trained subjects had less decline in and SV, %DeltaLV, and elevation in thoracic impedance. G-trained subjects also had greater total blood (6,497 +/- 496 vs. 5,438 +/- 228 ml, P = 0.07) and erythrocyte (3,110 +/- 364 vs. 2,310 +/- 96 ml, P = 0.06) volumes. These results support the hypothesis that exposure to repeated high G is associated with increased capacities of mechanisms that underlie blood pressure regulation. PMID:11247814

  2. Identifying Differences between Two Groups of High-Needs High Schools

    ERIC Educational Resources Information Center

    Englert, Kerry; Barley, Zoe A.

    2008-01-01

    This study examined differences in nine factors between a group of the highest-performing needs high schools (HPHN) and a group of the lowest performing high-needs (LPHN) high schools using teacher responses from a national dataset. The factors are: (1) shared mission and goals; (2) professional development; (3) collaboration among teachers (4)…

  3. The effects of catechin isolated from green tea GMB-4 on NADPH and nitric oxide levels in endothelial cells exposed to high glucose

    PubMed Central

    Peristiowati, Yuly; Indasah, Indasah; Ratnawati, Retty

    2015-01-01

    Aim: This study aimed to investigate whether a catechin isolated from GMB-4 green tea is able to increase the reducing equivalent system and nitric oxide (NO) level in endothelial cells exposed to high glucose (HG) level. Materials and Methods: Endothelial cells were obtained from human umbilical vascular tissues. At confluent, human endothelial cells were divided into five groups, which included control (untreated), endothelial cells exposed to HG (30 mM), endothelial cells exposed to HG in the presence of green tea catechin (HG + C) at the following three doses: 0.03; 0.3; and 3 mg/ml. Analysis of NADP+, NADPH, and NO levels were performed colorimetrically. Results: This decrease in NADPH was significantly (P < 0.05) attenuated by both the 0.3 and 3 mg/ml treatments of catechin. HG level significantly decreased NO compared with untreated cells. This increase in NO was significantly attenuated by the 0.3 mg/ml dose of the catechin. Conclusion: In conclusion, catechin isolated from GMB-4 green tea prohibits the decrease in NADPH and NO in endothelial cells induced by HG. Therefore this may provide a natural therapy for attenuating the endothelial dysfunction found in diabetes mellitus. PMID:26401396

  4. Studies of radiation damage to CAMEX64 preamplifiers exposed to γ-rays at the Cornell high energy synchrotron source

    NASA Astrophysics Data System (ADS)

    Alexander, J. P.; Bebek, C.; Browder, T. E.; Dobbins, J. A.; Gray, S. G.; Honscheid, K.; Jones, C. D.; Katayama, N.; Katris, J. S.; Kim, P. C.; Selen, M.; Worden, H. M.; Würthwein, F.; Cinabro, D.; Henderson, S.; Yamamoto, H.; Artuso, M.; Sobolewski, Z.; Akerib, D.; Chadha, M.; Chan, S.; Cowen, D. F.; Miller, J. S.; Gronberg, J.; Korte, C.; Morrison, R. J.; Nelson, H. N.; Nelson, T. K.; Schmidt, D. M.; Sperka, D.; Qiao, C.; Tajima, H.; Balest, R.; Smith, J. G.

    1993-12-01

    CAMEX64 preamplifiers, developed at the MPI-Munich for use in the readout of silicon strip detectors, have been exposed to well-measured doses of monochromatic γ-rays from the Cornell high energy synchrotron source (CHESS) and measurements of the resulting radiation damage have been made. Silicon strip detectors with their associated CAMEXes will be installed close to the interaction region in the CLEO-II experiment at Cornell University, where they will be exposed to both charged particle and photon fluences. Powered and unpowered CAMEXes were irradiated and after each exposure measurements of pedestals, gains, coherent and incoherent noise were made, until the devices could no longer be read out. Results are quoted for noise and gain degradation as a function of dose.

  5. Delivering asthma education to special high risk groups.

    PubMed

    FitzGerald, J M; Turner, M O

    1997-12-01

    Patients at high risk from their asthma and therefore worthy of more focused asthma education are those at risk of fatal and near fatal asthma(NFA). In recent years the characteristics of these patients have been better defined. The most important risk factor appears to be a prior history of NFA. Other important features include prior emergency room visits or hospitalization for asthma. Excess use of beta-agonists, especially in the absence of inhaled corticosteroids, also confers increased risk. High risk groups also share similar psychosocial barriers as well as economic deprivation. The benefits of asthma education in these groups have been assessed in a number of studies. In general, asthma education has been shown to have an impact on these patients. Greater effects have been achieved where there has been consistent follow-up by the same physician. Patients require frequent reinforcement of their asthma management, especially regarding their response to acute exacerbations. A sub-group of patients with more severe asthma appear to have a problem perceiving dyspnoea and may therefore benefit from peak flow monitoring but the problem of compliance with this intervention is significant. Behaviour modification plays an important role as does ensuring the patient has adequate resources to purchase medications especially the more expensive anti-inflammatory therapy. Future studies should focus on optimizing the potential benefits of educating high risk patients as they are not only those at greatest risk of death but also consume a disproportionate amount of health care resources.

  6. Diagnosis and Management of High Risk Group for Gastric Cancer

    PubMed Central

    Yoon, Hyuk; Kim, Nayoung

    2015-01-01

    Gastric cancer is associated with high morbidity and mortality worldwide. To reduce the socioeconomic burden related to gastric cancer, it is very important to identify and manage high risk group for gastric cancer. In this review, we describe the general risk factors for gastric cancer and define high risk group for gastric cancer. We discuss strategies for the effective management of patients for the prevention and early detection of gastric cancer. Atrophic gastritis (AG) and intestinal metaplasia (IM) are the most significant risk factors for gastric cancer. Therefore, the accurate selection of individuals with AG and IM may be a key strategy for the prevention and/or early detection of gastric cancer. Although endoscopic evaluation using enhanced technologies such as narrow band imaging-magnification, the serum pepsinogen test, Helicobacter pylori serology, and trefoil factor 3 have been evaluated, a gold standard method to accurately select individuals with AG and IM has not emerged. In terms of managing patients at high risk of gastric cancer, it remains uncertain whether H. pylori eradication reverses and/or prevents the progression of AG and IM. Although endoscopic surveillance in high risk patients is expected to be beneficial, further prospective studies in large populations are needed to determine the optimal surveillance interval. PMID:25547086

  7. Diagnosis and management of high risk group for gastric cancer.

    PubMed

    Yoon, Hyuk; Kim, Nayoung

    2015-01-01

    Gastric cancer is associated with high morbidity and mortality worldwide. To reduce the socioeconomic burden related to gastric cancer, it is very important to identify and manage high risk group for gastric cancer. In this review, we describe the general risk factors for gastric cancer and define high risk group for gastric cancer. We discuss strategies for the effective management of patients for the prevention and early detection of gastric cancer. Atrophic gastritis (AG) and intestinal metaplasia (IM) are the most significant risk factors for gastric cancer. Therefore, the accurate selection of individuals with AG and IM may be a key strategy for the prevention and/or early detection of gastric cancer. Although endoscopic evaluation using enhanced technologies such as narrow band imaging-magnification, the serum pepsinogen test, Helicobacter pylori serology, and trefoil factor 3 have been evaluated, a gold standard method to accurately select individuals with AG and IM has not emerged. In terms of managing patients at high risk of gastric cancer, it remains uncertain whether H. pylori eradication reverses and/or prevents the progression of AG and IM. Although endoscopic surveillance in high risk patients is expected to be beneficial, further prospective studies in large populations are needed to determine the optimal surveillance interval.

  8. The prevalence of stunting is high in HIV-1-exposed uninfected infants in Kenya.

    PubMed

    McGrath, Christine J; Nduati, Ruth; Richardson, Barbra A; Kristal, Alan R; Mbori-Ngacha, Dorothy; Farquhar, Carey; John-Stewart, Grace C

    2012-04-01

    As prevention of mother-to-child HIV-1 transmission (PMTCT) programs decrease the numbers of HIV-1-infected infants, it remains important to improve growth in HIV-1-exposed, uninfected (EU) infants. To determine the growth rate and predictors of growth faltering in breast-fed and formula-fed EU infants, growth analyses [weight-for-age (WAZ), weight-for-length (WLZ), and length-for-age (LAZ) Z-scores] were conducted by using data from a randomized feeding trial in HIV-1-infected women in Kenya. Growth faltering in EU infants was compared based on randomization to breastfeeding (BF) or formula feeding (FF) using Cox proportional hazards regression models. Linear mixed-effects models determined rate and cofactors of length growth. Among 338 EU infants, 164 (49%) were breast-fed and 174 (51%) formula-fed. In both arms, growth declined steadily during follow-up. By 2 y, 29% of children were underweight (WAZ < -2), 18% were wasted (WLZ < -2), and 58% were stunted (LAZ < -2), with no differences by feeding arm. Higher maternal education (y) and taller stature (cm) were associated with a decreased risk of underweight and stunting [underweight: adjusted HR (aHR) = 0.90 (95% CI: 0.83, 0.99), P = 0.03, and aHR = 0.92 (95% CI: 0.87, 0.97), P = 0.002; and stunting: aHR = 0.91 (95% CI: 0.85, 0.97), P = 0.003, and aHR = 0.96 (95% CI: 0.92, 0.99), P = 0.02, respectively]. Diarrhea was associated with an increased risk of wasting [aHR = 2.26 (95% CI: 1.11, 4.62), P = 0.03]. In multivariate analyses, FF was associated with slower declines in length velocity [0.24 LAZ/y (95% CI: 0.06, 0.43), P = 0.009]. Despite being uninfected, HIV-1-exposed infants showed frequent growth faltering, suggesting the need for vigilance in recognizing stunting within PMTCT programs. The slower rate of decline in length growth with FF may reflect benefits of micronutrients. Because BF is the best option for HIV-1-infected mothers in resource-limited settings, nutritional interventions should be examined

  9. Activation of the Cardiac Renin-Angiotensin System in High Oxygen-Exposed Newborn Rats: Angiotensin Receptor Blockade Prevents the Developmental Programming of Cardiac Dysfunction.

    PubMed

    Bertagnolli, Mariane; Dios, Anne; Béland-Bonenfant, Sarah; Gascon, Gabrielle; Sutherland, Megan; Lukaszewski, Marie-Amélie; Cloutier, Anik; Paradis, Pierre; Schiffrin, Ernesto L; Nuyt, Anne Monique

    2016-04-01

    Newborn rats exposed to high oxygen (O2), mimicking preterm birth-related neonatal stress, develop later in life cardiac hypertrophy, dysfunction, fibrosis, and activation of the renin-angiotensin system. Cardiac renin-angiotensin system activation in O2-exposed adult rats is characterized by an imbalance in angiotensin (Ang) receptors type 1/2 (AT1/2), with prevailing AT1 expression. To study the role of renin-angiotensin system in the developmental programming of cardiac dysfunction, we assessed Ang receptor expression during neonatal high O2 exposure and whether AT1 receptor blockade prevents cardiac alterations in early adulthood. Sprague-Dawley newborn rats were kept with their mother in 80% O2 or room air (control) from days 3 to 10 (P3-P10) of life. Losartan or water was administered by gavage from P8 to P10 (n=9/group). Rats were studied at P3 (before O2 exposure), P5, P10 (end of O2), and P28. Losartan treatment had no impact on growth or kidney development. AT1 and Ang type 2 receptors were upregulated in the left ventricle by high O2 exposure (P5 and P10), which was prevented by Losartan treatment at P10. Losartan prevented the cardiac AT1/2 imbalance at P28. Losartan decreased cardiac hypertrophy and fibrosis and improved left ventricle fraction of shortening in P28 O2-exposed rats, which was associated with decreased oxidation of calcium/calmodulin-dependent protein kinase II, inhibition of the transforming growth factor-β/SMAD3 pathway, and upregulation of cardiac angiotensin-converting enzyme 2. In conclusion, short-term Ang II blockade during neonatal high O2 prevents the development of cardiac alterations later in life in rats. These findings highlight the key role of neonatal renin-angiotensin system activation in the developmental programming of cardiac dysfunction induced by deleterious neonatal conditions.

  10. Oxidative stress in earthworms short- and long-term exposed to highly Hg-contaminated soils.

    PubMed

    Colacevich, Andrea; Sierra, María J; Borghini, Francesca; Millán, Rocio; Sanchez-Hernandez, Juan C

    2011-10-30

    Exposure to mercury is often assessed by the measurement of molecular and biochemical antioxidant defences against an excessive production of reactive oxygen species. Here we examined some selected biomarkers of oxidative stress in the earthworm Lumbricus terrestris short- (2d) and long-term (44 d) exposed to Hg-contaminated soils (up to 1287 mg/kg dry wt). This level of Hg exposure did not cause earthworm mortality, however it yielded organisms to a situation of oxidative stress which was evidenced by the time-dependent responses of biomarkers. The reduced to oxidized glutathione ratio was a sensitive and early biomarker of Hg exposure, although the glutathione reductase activity back returned their normal physiological concentrations. Metallothioneins and total glutathione seemed to have a significant role in reducing Hg-induced oxidative stress when exposure to Hg prolonged up to 44 d. We combined biomarker responses into an integrate biomarker index which positively correlated with the Hg concentrations measured in the postmitochondrial fraction of the earthworm muscle, and with the available Hg fraction in soil. Current results suggest that glutathione redox cycle can be a complementary tool in the exposure and effect assessment of Hg-polluted soils. PMID:21871720

  11. [Bone disorders in children with chronic renal insufficiency exposed to high ingestion of aluminum].

    PubMed

    Gordillo-Paniagua, G; Valencia-Mayoral, P; Mercado, L; Medina-Mercado, M

    1990-05-01

    Bone disorders in 28 children with chronic renal failure exposed to aluminum intoxication were studied. All of the children were in the dialysis program. Aluminum blood levels were higher than normal in all of the children and without any correlation to the magnitude of hypocalcemia or with the increase of the parathormone, which were found in different amounts in all of the children. All of the children had various degrees of skeletal retardation and only one had pathological fractures. The bone biopsy showed hypocellular marrow, decreased osteoclastic activity in the majority of the cases same as trabecular mineralization, although the amount of osteoid was lacking in the trabeculae in the majority of the cases. The deposit of aluminum was detected in a great number of them. It is concluded that osteodystrophy recognizes a number of factors as may be hypocalcemia due to a decrease in the production of 1,25-cholecalciferol, an increase in the parathyroid hormone and the deposit of aluminum, coming mainly from water, in the trabeculae which interfere with the incorporation of calcium in the formation of new bone.

  12. [Pathophysiological changes in mitochondria of mammalian exposed to hypoxia at high altitude].

    PubMed

    Gao, Wen-xiang; Wu, Gang; Gao, Yu-qi

    2014-11-01

    As human beings ascend to high altitude, a number of reactions may occur against hypoxic injuries. These hypoxic responses are related to intake, transportation and utility of the oxygen. As a crucial subcellular organelle of oxygen utility, mitochondrion is a central link of high altitude acclimatization, adaptation and mountain sicknesses. In this review, we discussed the recent advances in researches on hypoxic mitochondrial responses at high altitude. PMID:26016358

  13. Pressure-induced phase transitions of exposed curved surface nano-TiO2 with high photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Huang, Yanwei; Chen, Fengjiao; Li, Xin; Yuan, Ye; Dong, Haini; Samanta, Sudeshna; Yu, Zhenhai; Rahman, Saqib; Zhang, Jun; Yang, Ke; Yan, Shuai; Wang, Lin

    2016-06-01

    We report a unique phase transition in compressed exposed curved surface nano-TiO2 with high photocatalytic activity using in situ synchrotron X-ray diffraction and Raman Spectroscopy. High-pressure studies indicate that the anatase phase starts to transform into baddeleyite phase upon compression at 19.4 GPa, and completely transforms into the baddeleyite phase above 24.6 GPa. Upon decompression, the baddeleyite phase was maintained until the pressure was released to 6.4 GPa and then transformed into the α-PbO2 phase at 2.7 GPa. Together with the results of high-resolution transmission electron microscopy and the pressure-volume relationship, this phase transition's characteristics during the compression-decompression cycle demonstrate that the truncated biconic morphology possessed excellent stability. This study may provide an insight to the mechanisms of stability for high photocatalytic activity of nano-TiO2.

  14. Potential approaches to the spectroscopic characterization of high performance polymers exposed to energetic protons and heavy ions

    NASA Technical Reports Server (NTRS)

    Suleman, Naushadalli K.

    1991-01-01

    A potential limitation to human activity on the lunar surface or in deep space is the exposure of the crew to unacceptably high levels of penetrating space radiations. The radiations of most concerns for such missions are high-energy protons emitted during solar flares, and galactic cosmic rays which are high-energy ions ranging from protons to iron. The development of materials for effective shielding from energetic space radiations will clearly require a greater understanding of the underlying mechanisms of radiation-induced damage in bulk materials. This can be accomplished in part by the detailed spectroscopic characterization of bulk materials that were exposed to simulated space radiations. An experimental data base thus created can then be used in conjunction with existing radiation transport codes in the design and fabrication of effective radiation shielding materials. Electron Paramagnetic Resonance Spectroscopy was proven very useful in elucidating radiation effects in polymers (high performance polymers are often an important components of structural composites).

  15. Indiana University High Energy Physics Group, Task E

    SciTech Connect

    Alyea, E.D. Jr.

    1991-01-01

    This progress report for Task E of the Indiana University High Energy Physics Group covers the period June 1, 1990 to April 15, 1991. All my research effort was devoted to the Large Volume Detector (LVD) at the Gran Sasso Laboratory in Italy. The first of five towers'' of LVD is currently under construction. My primary effort during this time has been to bring to fruition the cabling plans developed by me the previous year. Other activities have included consultations on the design of the tracking trigger electronics, work on several hardware systems for the direct mount tracking modules, and coordination of various projects at the Gran Sasso Lab.

  16. Ultrasonic and metallographic studies on AISI 4140 steel exposed to hydrogen at high pressure and temperature

    NASA Astrophysics Data System (ADS)

    Oruganti, Malavika

    This thesis conducts an investigation to study the effects of hydrogen exposure at high temperature and pressure on the behavior of AISI 4140 steel. Piezoelectric ultrasonic technique was primarily used to evaluate surface longitudinal wave velocity and defect geometry variations, as related to time after exposure to hydrogen at high temperature and pressure. Critically refracted longitudinal wave technique was used for the former and pulse-echo technique for the latter. Optical microscopy and scanning electron microscopy were used to correlate the ultrasonic results with the microstructure of the steel and to provide better insight into the steel behavior. The results of the investigation indicate that frequency analysis of the defect echo, determined using the pulse-echo technique at regular intervals of time, appears to be a promising tool for monitoring defect growth induced by a high temperature and high pressure hydrogen-related attack.

  17. Distribution of Chromosome Breakpoints in Human Epithelial Cells Exposed to Low- and High-LET Radiation

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Zhang, Ye; Cucinotta, Francis A.; Feiveson, Alan; Wu, Honglu

    2010-01-01

    Low-and high-LET radiations produced distinct breakpoint distributions. The difference of the breakpoint distributions between low-and high-LET only appeared in break ends involved in interchromosome exchanges. The breakpoint distributions for break ends participating in intrachromosome exchanges were similar. Gene-rich regions do not necessarily have more chromosome breaks. High-LET appeared to produce long live (data not shown) or longer live breaks that can migrate a longer distance before rejoining with other breaks. Domains occupied by different segments of the chromosomes may be responsible for the breakpoint distribution. The dose responses for interchromosomal exchanges were linear in all four exposures. However, the dose response for intrachromosomal exchanges were none linear. Increasing dose of high dose rate exposure (Fe-ions or -rays) increase the fraction of cells with intrachromosome aberrations, whereas increasing dose of low dose rate exposure (neutrons or -rays) does not affect the fraction of cells with intrachromosome aberrations.

  18. Distinct vasopressin content in the hypothalamic supraoptic and paraventricular nucleus of rats exposed to low and high ambient temperature.

    PubMed

    Jasnic, N; Dakic, T; Bataveljic, D; Vujovic, P; Lakic, I; Jevdjovic, T; Djurasevic, S; Djordjevic, J

    2015-08-01

    Both high and low ambient temperature represent thermal stressors that, among other physiological responses, induce activation of the hypothalamic-pituitary-adrenal (HPA) axis and secretion of arginine-vasopressin (AVP). The exposure to heat also leads to disturbance of osmotic homeostasis. Since AVP, in addition to its well-known peripheral effects, has long been recognized as a hormone involved in the modulation of HPA axis activity, the aim of the present study was to elucidate the hypothalamic AVP amount in the acutely heat/cold exposed rats. Rats were exposed to high (+38°C) or low (+4°C) ambient temperature for 60min. Western blot was employed for determining hypothalamic AVP levels, and the difference in its content between supraoptic (SON) and paraventricular nucleus (PVN) was detected using immunohistochemical analysis. The results showed that exposure to both high and low ambient temperature increased hypothalamic AVP levels, although the increment was higher under heat conditions. On the other hand, patterns of AVP level changes in PVN and SON were stressor-specific, given that exposure to cold increased the AVP level in both nuclei, while heat exposure affected the PVN AVP content alone. In conclusion, our results revealed that cold and heat stress influence hypothalamic AVP amount with different intensity. Moreover, different pattern of AVP amount changes in the PVN and SON indicates a role of this hormone not only in response to heat as an osmotic/physical threat, but to the non-osmotic stressors as well.

  19. High-temperature-oxidation-induced ordered structure in Inconel 939 superalloy exposed to oxy-combustion environments

    SciTech Connect

    Zhu, Jingxi; Wise, Adam; Nuhfer, Thomas; Holcomb, Gordon R; Jablonski, Paul D; Sridhar, Seetharaman; Laughlin, David E

    2013-04-20

    In the integrated oxy-fuel combustion and turbine power generation system, turbine alloys are exposed to high temperature and an atmosphere comprised of steam, CO2 and O2. While surface and internal oxidation of the alloy takes place, the microstructure in the subsurface region also changes due to oxidation that results in the loss of the strengthening precipitates. In an earlier study of the oxidation of Inconel 939 Ni-based superalloy exposed to oxy-fuel combustion environment for up to 1000 hours, a high-temperature-oxidation-induced phase transformation in the sub-surface region was noticed and a two-phase region formed at the expense of strengthening γ' phase. While one of the two phases was identified as the Ni-matrix (γ solid solution, face-center-cubic) phase, the other product phase remained unidentified. In this study, the crystal structure of the unknown phase and its orientation relationship with the parent Ni-matrix phase was investigated through electron diffraction and high-resolution transmission electron microscopy. It was determined that the crystal structure of the unknown phase could be modeled as a ternary derivative of the ordered η-Ni3Ti phase (D024) structure with lattice parameters of a = 0.5092 nm and c = 0.8336 nm, α = 90º, β = 90º and γ = 120º.

  20. Physiological and molecular alterations in plants exposed to high [CO2] under phosphorus stress.

    PubMed

    Pandey, Renu; Zinta, Gaurav; AbdElgawad, Hamada; Ahmad, Altaf; Jain, Vanita; Janssens, Ivan A

    2015-01-01

    Atmospheric [CO2] has increased substantially in recent decades and will continue to do so, whereas the availability of phosphorus (P) is limited and unlikely to increase in the future. P is a non-renewable resource, and it is essential to every form of life. P is a key plant nutrient controlling the responsiveness of photosynthesis to [CO2]. Increases in [CO2] typically results in increased biomass through stimulation of net photosynthesis, and hence enhance the demand for P uptake. However, most soils contain low concentrations of available P. Therefore, low P is one of the major growth-limiting factors for plants in many agricultural and natural ecosystems. The adaptive responses of plants to [CO2] and P availability encompass alterations at morphological, physiological, biochemical and molecular levels. In general low P reduces growth, whereas high [CO2] enhances it particularly in C3 plants. Photosynthetic capacity is often enhanced under high [CO2] with sufficient P supply through modulation of enzyme activities involved in carbon fixation such as ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). However, high [CO2] with low P availability results in enhanced dry matter partitioning towards roots. Alterations in below-ground processes including root morphology, exudation and mycorrhizal association are influenced by [CO2] and P availability. Under high P availability, elevated [CO2] improves the uptake of P from soil. In contrast, under low P availability, high [CO2] mainly improves the efficiency with which plants produce biomass per unit P. At molecular level, the spatio-temporal regulation of genes involved in plant adaptation to low P and high [CO2] has been studied individually in various plant species. Genome-wide expression profiling of high [CO2] grown plants revealed hormonal regulation of biomass accumulation through complex transcriptional networks. Similarly, differential transcriptional regulatory networks are involved in P

  1. High mortality rates occur in copper deficient rats exposed to a normally nonlethal endotoxin treatment

    SciTech Connect

    DiSilvestro, R.; Joseph, E.; Yang, F.L. )

    1991-03-15

    Endotoxin hepatotoxicity is proposed to occur by processes which could be retarded by 3 copper enzymes: ceruloplasmin, Cu-Zn superoxide dismutase (SOD), and extracellular (EC) SOD. Weanling rats fed low copper for 40 days showed low activity levels of these enzymes, and a very high mortality rate 20 h after endotoxin injection. No rats fed adequate copper died from this treatment. In addition, serum transaminase activities, indicators of liver damage, were elevated by 3 h to a greater extent in the deficient rats than in the adequates. The high susceptibility to endotoxemia in the deficient rats was not associated with low hepatic glutathione, high liver malondialedhyde, nor restricted metallothionein induction 3 h after endotoxin injection. Endotoxin reduced serum EC SOD activities in adequate and deficient rats, but final values were lower in the latter. Studies on roles of specific copper enzymes in resistance to endotoxemia are currently underway.

  2. Modulation of lipid metabolism in glycyrrhizic acid-treated rats fed on a high-calorie diet and exposed to short or long-term stress.

    PubMed

    Yaw, Hui Ping; Ton, So Ha; Chin, Hsien-Fei; Karim, Muhammad Kaiser Abdul; Fernando, Hamish Alexander; Kadir, Khalid Abdul

    2015-01-01

    Stress and high-calorie diets increase the risk of developing metabolic syndrome. Glycyrrhizic acid (GA) has been shown to improve dyslipidaemia in rats fed on a high-calorie diet. This study aimed to examine the effects of GA on lipid metabolism in rats exposed to short- or long-term stress and on a high-calorie diet. The parameters examined included serum lipid profiles, serum free fatty acids and fatty acid profiles in tissues, and expression of peroxisome proliferator-activated receptors (PPAR), lipoprotein lipase (LPL), elongases and desaturases. Within the 14- or 28-day exposure groups, neither stress nor GA affected the lipid profile and serum free fatty acids. Stress did not affect PPAR-α expression in both the 14- and 28-day exposure groups. However, GA-treated rats from the former group had increased PPAR-α expression only in the kidney while all other tissues from the latter group were unaffected. Stress increased PPAR-γ expression in the heart of the 28-day exposure group but its expression was unaffected in all tissues of the 14-day exposure group. GA elevated PPAR-γ expression in the kidney and the skeletal muscles. Neither stress nor GA affected LPL expressions in all tissues from the 14-day exposure group but its expressions were elevated in the QF of the stressed rats and heart of the GA-treated rats of the 28-day exposure group. As for the elongases and desaturases in the liver, stress down-regulated ELOVL5 in the long-term exposure group while up-regulated ELOVL6 in the short-term exposure group while hepatic desaturases were unaffected by stress. Neither elongase nor desaturase expressions in the liver were affected by GA. This research is the first report of GA on lipid metabolism under stress and high-calorie diet conditions and the results gives evidence for the role of GA in ameliorating MetS via site-specific regulation of lipid metabolism gene expressions and modification of fatty acids.

  3. Modulation of lipid metabolism in glycyrrhizic acid-treated rats fed on a high-calorie diet and exposed to short or long-term stress

    PubMed Central

    Yaw, Hui Ping; Ton, So Ha; Chin, Hsien-Fei; Karim, Muhammad Kaiser Abdul; Fernando, Hamish Alexander; Kadir, Khalid Abdul

    2015-01-01

    Stress and high-calorie diets increase the risk of developing metabolic syndrome. Glycyrrhizic acid (GA) has been shown to improve dyslipidaemia in rats fed on a high-calorie diet. This study aimed to examine the effects of GA on lipid metabolism in rats exposed to short- or long-term stress and on a high-calorie diet. The parameters examined included serum lipid profiles, serum free fatty acids and fatty acid profiles in tissues, and expression of peroxisome proliferator-activated receptors (PPAR), lipoprotein lipase (LPL), elongases and desaturases. Within the 14- or 28-day exposure groups, neither stress nor GA affected the lipid profile and serum free fatty acids. Stress did not affect PPAR-α expression in both the 14- and 28-day exposure groups. However, GA-treated rats from the former group had increased PPAR-α expression only in the kidney while all other tissues from the latter group were unaffected. Stress increased PPAR-γ expression in the heart of the 28-day exposure group but its expression was unaffected in all tissues of the 14-day exposure group. GA elevated PPAR-γ expression in the kidney and the skeletal muscles. Neither stress nor GA affected LPL expressions in all tissues from the 14-day exposure group but its expressions were elevated in the QF of the stressed rats and heart of the GA-treated rats of the 28-day exposure group. As for the elongases and desaturases in the liver, stress down-regulated ELOVL5 in the long-term exposure group while up-regulated ELOVL6 in the short-term exposure group while hepatic desaturases were unaffected by stress. Neither elongase nor desaturase expressions in the liver were affected by GA. This research is the first report of GA on lipid metabolism under stress and high-calorie diet conditions and the results gives evidence for the role of GA in ameliorating MetS via site-specific regulation of lipid metabolism gene expressions and modification of fatty acids. PMID:26069530

  4. A Public Relations Nightmare: ACLU Class Action Lawsuit Exposes Inaccurate and Inequitable High School Graduation Rates

    ERIC Educational Resources Information Center

    Watson, Terri N.; Brown, Kathleen M.

    2010-01-01

    Florida's decision to equate a GED to a high school diploma undermines the attempt of No Child Left Behind to close the achievement gap, while infringing on the public's trust. Public trust fosters a culture of systemic equity and social justice, which are necessary for academic excellence (Byrk & Schneider, 2003). Florida's code of ethics for…

  5. High-Fidelity Patient Simulators to Expose Undergraduate Students to the Clinical Relevance of Physiology Concepts

    ERIC Educational Resources Information Center

    Harris, David M.; Bellew, Christine; Cheng, Zixi J.; Cendán, Juan C.; Kibble, Jonathan D.

    2014-01-01

    The use of high-fidelity patient simulators (HFPSs) has expanded throughout medical, nursing, and allied health professions education in the last decades. These manikins can be programmed to represent pathological states and are used to teach clinical skills as well as clinical reasoning. First, the students are typically oriented either to the…

  6. A follow-up cytogenetic study of workers highly exposed inside the Chernobyl sarcophagus.

    PubMed

    Khvostunov, I K; Snigiryova, G P; Moiseenko, V V; Lloyd, D C

    2015-12-01

    Data are presented on some of the engineers and scientists who regularly entered highly radioactive areas of the sarcophagus chamber constructed around the ruins of the Chernobyl reactor. Previous investigations on six of them by unstable chromosomal aberrations, quartz fibre electrometers and, in some cases, tooth electron spin resonance have all indicated high doses accumulated over several years of work inside the sarcophagus. Here, the authors present the data on eleven of the men who agreed to be monitored cytogenetically although two have since died aged 45 and 66 y. The present data were combined with the previous to examine the time-courses of these individuals' changes in their aberration frequencies. As expected, dicentric aberrations showed a clear drop down to 2-3 per 100 cells since the men ceased working inside the sarcophagus. In contrast, the translocation yields remained at a high level showing no tendency to decrease and so proved reliable for retrospective biodosimetry. These data are particularly useful in demonstrating the value of FISH long after high but protracted and fractionated exposure.

  7. Activity patterns in elementary and high school students exposed to oxidant pollution

    SciTech Connect

    Spier, C.E.; Little, D.E.; Trim, S.C.; Johnson, T.R.; Linn, W.S.; Hackney, J.D. )

    1992-07-01

    We investigated activity patterns of 17 elementary school students aged 10-12, and 19 high school students aged 13-17, in suburban Los Angeles during the oxidant pollution season. Individuals' relationships between ventilation rate (VR) and heart rate (HR) were calibrated' in supervised outdoor walking/jogging. Log VR was consistently proportional to HR; although calibrations' were limited by a restricted range of exercise, and possibly by artifact due to mouthpiece breathing, which may cause overestimation of VR at rest. Each subject then recorded activities in diaries, and recorded HR once per minute by wearing Heart Watches, over 3 days (Saturday-Monday). For each activity the subject estimated a breathing rate--slow (slow walking), medium (fast walking), or fast (running). VR ranges for each breathing rate and activity type were estimated from HR recordings. High-school students' diaries showed their aggregate distribution of waking hours as 68% slow inside, 8% slow outside, 10% medium inside, 9% medium outside, 1.5% fast inside, 1.5% fast outside. Elementary students' distribution was 47% slow inside, 15% slow outside, 20% medium inside, 12% medium outside, 2.5% fast inside, 3.5% fast outside. Sleep occupied 38% of high-school students' and 40% of elementary students' time; HR were generally lower in sleep than in slow waking activity. High school students' mean VR estimates were 13 L/min for slow breathing, 18 for medium, and 23 for fast; elementary students' were 14 slow, 18 medium, and 19 fast. VR distributions were approximately lognormal. Maximum estimated VR were approximately 70 L/min in elementary and approximately 100 L/min in high school students. Compared to adults studied similarly, students reported more medium or fast breathing, and had equal or higher VR estimates during slow and medium breathing despite their smaller size. These results suggest that, relative to body size, young people inhale larger doses of outdoor air pollutants than adults.

  8. Mutagenic adaptive response to high-LET radiation in human lymphoblastoid cells exposed to X-rays.

    PubMed

    Varès, Guillaume; Wang, Bing; Tanaka, Kaoru; Kakimoto, Ayana; Eguchi-Kasai, Kyomi; Nenoi, Mitsuru

    2011-01-10

    The ability of cells to adapt low-dose or low-dose rate radiation is well known. High-LET radiation has unique characteristics, and the data concerning low doses effects and high-LET radiation remain fragmented. In this study, we assessed in vitro the ability of low doses of X-rays to induce an adaptive response (AR) to a subsequent challenging dose of heavy-ion radiation. Lymphoblastoid cells (TK6, AHH-1, NH32) were exposed to priming 0.02-0.1Gy X-rays, followed 6h later by challenging 1Gy heavy-ion radiation (carbon-ion: 20 and 40keV/μm, neon-ion: 150keV/μm). Pre-exposure of p53-competent cells resulted in decreased mutation frequencies at hypoxanthine-guanine phosphoribosyl transferase locus and different H2AX phosphorylation kinetics, as compared to cells exposed to challenging radiation alone. This phenomenon did not seem to be linked with cell cycle effects or radiation-induced apoptosis. Taken together, our results suggested the existence of an AR to mutagenic effects of heavy-ion radiation in lymphoblastoid cells and the involvement of double-strand break repair mechanisms.

  9. Calcium homeostasis of isolated heart muscle cells exposed to pulsed high-frequency electromagnetic fields

    SciTech Connect

    Wolke, S.; Gollnick, F.; Meyer, R.; Neibig, U.; Elsner, R.

    1996-05-01

    The intracellular calcium concentration ([Ca{sup 2+}]{sub i}) of isolated ventricular cardiac myocytes of the guinea pig was measured during the application of pulsed high-frequency electromagnetic fields. The high-frequency fields were applied in a transverse electromagnetic cell designed to allow microscopic observation of the myocytes during the presence of the high-frequency fields. The [Ca{sup 2+}]{sub i} was measured as fura-2 fluorescence by means of digital image analysis. Both the carrier frequency and the square-wave pulse-modulation pattern were varied during the experiments (carrier frequencies: 900, 1,300, and 1,800 MHz pulse modulated at 217 Hz with 14% duty cycle; pulsation pattern at 900 MHz; continuous wave, 16 Hz,and 50 Hz modulation with 50% duty cycle and 30 kHz modulation with 80% duty cycle). The mean specific absorption rate (SAR) values in the solution were within one order of magnitude of 1 mW/kg. They varied depending on the applied carrier frequency and pulse pattern. The experiments were designed in three phases: 500 s of sham exposure, followed by 500 s of field exposure, then chemical stimulation without field. The chemical stimulation (K{sup +}-depolarization) indicated the viability of the cells. The K{sup +} depolarization yielded a significant increase in [Ca{sup 2+}]{sub i}. Significant differences between sham exposure and high-frequency field exposure were not found except when a very small but statistically significant difference was detected in the case of 900 MHz/50 Hz. However, this small difference was not regarded as a relevant effect of the exposure.

  10. Abdominal Obesity and Insulin Resistance in People Exposed to Moderate-to-High Levels of Dioxin

    PubMed Central

    Chang, Jung-Wei; Chen, Hsiu-Ling; Su, Huey-Jen; Lee, Ching-Chang

    2016-01-01

    Obesity, a risk factor for developing metabolic complications, is a major public health problem. Abdominal obesity is strongly accompanied by a cluster of metabolic abnormalities characterized by insulin resistance. The link between persistent organic pollutants (POPs) and insulin resistance has been investigated in animal and epidemiological studies. We aimed to examine whether insulin resistance is greater in people with abdominal obesity (AO) and concomitant exposure to serum dioxins (PCDD/Fs). We conducted a cross-sectional descriptive study of 2876 participants living near a PCDD/Fs contaminated area. Seventeen 2,3,7,8-substituted PCDD/Fs congeners were measured, and then the associations between the main predictor variable, serum TEQDF-1998, abdominal obesity (AO), dependent variables, and insulin resistance were examined. Twelve of the 17 congeners, widely distributed among PCDDs, and PCDFs, had trends for associations with abdominal adiposity. In men, the highest quintiles of 1,2,3,7,8-PeCDF; 1,2,3,7,8-PeCDD; 2,3,7,8-TCDD; 2,3,7,8-TCDF; and 2,3,4,7,8-PeCDF had the top five adjusted odds ratios (AORs) + 95% confidence intervals (CIs):[4.2; 2.7–6.4], [3.6; 2.3–5.7], [3.2; 2.1–5.0], [3.0; 2.0–4.5], and [2.9; 1.9–4.7], respectively. In women, the highest quintiles of 1,2,3,4,7,8,9-HpCDF; 1,2,3,6,7,8-HxCDF; and 1,2,3,4,6,7,8-HpCDF had the top three AORs + 95% CIs:[3.0; 1.9–4.7], [2.0; 1.3–3.1], and [1.9; 1.3–2.9], respectively. After confounding factors had been adjusted for, men, but not women, with higher serum TEQDF-1998 levels or abdominal obesity had a significantly (Ptrend < 0.001) greater risk for abnormal insulin resistance. The groups with the highest joint serum TEQDF-1998 and abdominal obesity levels were associated with elevated insulin resistance at 5.0 times the odds of the groups with the lowest joint levels (AOR 5.23; 95% CI: 3.53–7.77). We hypothesize that serum TEQDF-1998 and abdominal obesity affect the association with

  11. Exposing high-z obscured AGNs in the deepest IR/X-rays surveys

    NASA Astrophysics Data System (ADS)

    Daddi, Emanuele

    2012-01-01

    The identification and study of the elusive population of high redshift obscured AGNs is an important step towards understanding the fundamental phase of black hole growth in the young universe. Here we propose NIR spectroscopy with MOIRCS to confirm and characterize candidate high-z obscured/Compton-thick AGNs found in the deepest Herschel and X-ray surveys. The sample, designed to cover a range of redshifts (1.5 < z < 4), is selected from the GOODS field by use of Herschel+Spitzer (MIR to FIR colors and the presence of power-law MIR emission) and X-ray spectral properties from XMM and Chandra. The MOIRCS data are crucial to fully confirm and exploit our sample. The specific science goals include (a) obtaining independent AGN classifications and luminosities via rest-frame optical spectroscopy; (b) testing for the expected strong outflows in these high bolometric luminosity QSOs; (c) spectroscopically confirming redshifts of objects which currently have only z_phot. In the larger picture, this study will put stronger constraints on the number density of Compton-thick AGNs and on the evolution of supermassive black holes and their host galaxies.

  12. Factors influencing the inactivation of Alicyclobacillus acidoterrestris spores exposed to high hydrostatic pressure in apple juice

    NASA Astrophysics Data System (ADS)

    Sokołowska, B.; Skąpska, S.; Fonberg-Broczek, M.; Niezgoda, J.; Chotkiewicz, M.; Dekowska, A.; Rzoska, S. J.

    2013-03-01

    Alicyclobacillus acidoterrestris, a thermoacidophilic and spore-forming bacterium, survives the typical pasteurization process and can cause the spoilage of juices, producing compounds associated with disinfectant-like odour (guaiacol, 2,6 - dibromophenol, 2,6 - dichlorophenol). Therefore, the use of other more effective techniques such as high hydrostatic pressure (HHP) is considered for preserving juices. The aim of this study was to search for factors affecting the resistance of A. acidoterrestris spores to HHP. The baroprotective effect of increased solute concentration in apple juice on A. acidoterrestris spores during high pressure processing was observed. During the 45 min pressurization (200 MPa, 50°C) of the spores in concentrated apple juice (71.1°Bx), no significant changes were observed in their number. However, in the juices with a soluble solids content of 35.7, 23.6 and 11.2°Bx, the reduction in spores was 1.3-2.4 log, 2.6-3.3 log and 2.8-4.0 log, respectively. No clear effect of age of spores on the survival under high pressure conditions was found. Spores surviving pressurization and subjected to subsequent HHP treatment showed increased resistance to pressure, by even as much as 2.0 log.

  13. High prevalence of chitotriosidase deficiency in Peruvian Amerindians exposed to chitin-bearing food and enteroparasites

    PubMed Central

    Manno, N.; Sherratt, S.; Boaretto, F.; Coico, F. Mejìa; Camus, C. Espinoza; Campos, C. Jara; Musumeci, S.; Battisti, A.; Quinnell, R.J.; León, J. Mostacero; Vazza, G.; Mostacciuolo, M.L.; Paoletti, M.G.; Falcone, F.H.

    2014-01-01

    The human genome encodes a gene for an enzymatically active chitinase (CHIT1) located in a single copy on Chromosome 1, which is highly expressed by activated macrophages and in other cells of the innate immune response. Several dysfunctional mutations are known in CHIT1, including a 24-bp duplication in Exon 10 causing catalytic deficiency. This duplication is a common variant conserved in many human populations, except in West and South Africans. Thus it has been proposed that human migration out of Africa and the consequent reduction of exposure to chitin from environmental factors may have enabled the conservation of dysfunctional mutations in human chitinases. Our data obtained from 85 indigenous Amerindians from Peru, representative of populations characterized by high prevalence of chitin-bearing enteroparasites and intense entomophagy, reveal a very high frequency of the 24-bp duplication (47.06%), and of other single nucleotide polymorphisms which are known to partially affect enzymatic activity (G102S: 42.7% and A442G/V: 25.5%). Our finding is in line with a founder effect, but appears to confute our previous hypothesis of a protective role against parasite infection and sustains the discussion on the redundancy of chitinolytic function. PMID:25256524

  14. Evidence of sulfur-bound reduced copper in bamboo exposed to high silicon and copper concentrations.

    PubMed

    Collin, Blanche; Doelsch, Emmanuel; Keller, Catherine; Cazevieille, Patrick; Tella, Marie; Chaurand, Perrine; Panfili, Frédéric; Hazemann, Jean-Louis; Meunier, Jean-Dominique

    2014-04-01

    We examined copper (Cu) absorption, distribution and toxicity and the role of a silicon (Si) supplementation in the bamboo Phyllostachys fastuosa. Bamboos were maintained in hydroponics for 4 months and submitted to two different Cu (1.5 and 100 μm Cu(2+)) and Si (0 and 1.1 mM) concentrations. Cu and Si partitioning and Cu speciation were investigated by chemical analysis, microscopic and spectroscopic techniques. Copper was present as Cu(I) and Cu(II) depending on plant parts. Bamboo mainly coped with high Cu exposure by: (i) high Cu sequestration in the root (ii) Cu(II) binding to amino and carboxyl ligands in roots, and (iii) Cu(I) complexation with both organic and inorganic sulfur ligands in stems and leaves. Silicon supplementation decreased the visible damage induced by high Cu exposure and modified Cu speciation in the leaves where a higher proportion of Cu was present as inorganic Cu(I)S compounds, which may be less toxic.

  15. Highly adaptive tests for group differences in brain functional connectivity.

    PubMed

    Kim, Junghi; Pan, Wei

    2015-01-01

    Resting-state functional magnetic resonance imaging (rs-fMRI) and other technologies have been offering evidence and insights showing that altered brain functional networks are associated with neurological illnesses such as Alzheimer's disease. Exploring brain networks of clinical populations compared to those of controls would be a key inquiry to reveal underlying neurological processes related to such illnesses. For such a purpose, group-level inference is a necessary first step in order to establish whether there are any genuinely disrupted brain subnetworks. Such an analysis is also challenging due to the high dimensionality of the parameters in a network model and high noise levels in neuroimaging data. We are still in the early stage of method development as highlighted by Varoquaux and Craddock (2013) that "there is currently no unique solution, but a spectrum of related methods and analytical strategies" to learn and compare brain connectivity. In practice the important issue of how to choose several critical parameters in estimating a network, such as what association measure to use and what is the sparsity of the estimated network, has not been carefully addressed, largely because the answers are unknown yet. For example, even though the choice of tuning parameters in model estimation has been extensively discussed in the literature, as to be shown here, an optimal choice of a parameter for network estimation may not be optimal in the current context of hypothesis testing. Arbitrarily choosing or mis-specifying such parameters may lead to extremely low-powered tests. Here we develop highly adaptive tests to detect group differences in brain connectivity while accounting for unknown optimal choices of some tuning parameters. The proposed tests combine statistical evidence against a null hypothesis from multiple sources across a range of plausible tuning parameter values reflecting uncertainty with the unknown truth. These highly adaptive tests are not only

  16. Highly adaptive tests for group differences in brain functional connectivity.

    PubMed

    Kim, Junghi; Pan, Wei

    2015-01-01

    Resting-state functional magnetic resonance imaging (rs-fMRI) and other technologies have been offering evidence and insights showing that altered brain functional networks are associated with neurological illnesses such as Alzheimer's disease. Exploring brain networks of clinical populations compared to those of controls would be a key inquiry to reveal underlying neurological processes related to such illnesses. For such a purpose, group-level inference is a necessary first step in order to establish whether there are any genuinely disrupted brain subnetworks. Such an analysis is also challenging due to the high dimensionality of the parameters in a network model and high noise levels in neuroimaging data. We are still in the early stage of method development as highlighted by Varoquaux and Craddock (2013) that "there is currently no unique solution, but a spectrum of related methods and analytical strategies" to learn and compare brain connectivity. In practice the important issue of how to choose several critical parameters in estimating a network, such as what association measure to use and what is the sparsity of the estimated network, has not been carefully addressed, largely because the answers are unknown yet. For example, even though the choice of tuning parameters in model estimation has been extensively discussed in the literature, as to be shown here, an optimal choice of a parameter for network estimation may not be optimal in the current context of hypothesis testing. Arbitrarily choosing or mis-specifying such parameters may lead to extremely low-powered tests. Here we develop highly adaptive tests to detect group differences in brain connectivity while accounting for unknown optimal choices of some tuning parameters. The proposed tests combine statistical evidence against a null hypothesis from multiple sources across a range of plausible tuning parameter values reflecting uncertainty with the unknown truth. These highly adaptive tests are not only

  17. Deer exposed to exceptionally high concentrations of lead near the continental mine in Idaho, USA

    USGS Publications Warehouse

    Beyer, W.N.; Gaston, G.; Brazzle, R.; O'Connell, A.F.; Audet, D.J.

    2007-01-01

    Habitat surrounding the inactive Continental Mine in northern Idaho, USA, supports bear (Ursus arctos, Ursus americanus), moose (Alces alces), elk (Cervus elaphus), woodland caribou (Rangifer tarandus caribou), and abundant mule (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus). Tailings on the mining site were capped and remediated in 2003 to reduce environmental exposure of surrounding soil and sediments of Blue Joe Creek, downslope of the mine. Before capping, the mean Pb concentration in deer pellets collected on-site was 920 mg/kg of Pb (dry wt). This exposure, if chronic, would be comparable to an exposure that could be lethal to cattle or horses. Surprisingly, the mean pellet Pb concentration of 950 mg/kg in 2004 was as high as it was before remediation, and it was related to a high rate of soil ingestion. Mean soil content of the pellets collected from the capped site in 2004 was 22% dry weight, estimated from the acid-insoluble ash, a marker of soil ingestion. Clumps of sand and bits of rock were observed inside some of the pellets, and Pb concentrations in the pellets were correlated (p < 0.05) with soil content. Although terrestrial risk assessments generally estimate exposure from diets and from incidentally ingested soil, the deer at this site were directly ingesting contaminated soil or mining waste. The mean Pb concentration of this ingested soil was estimated as 6,700 mg/kg and the maximum as 25,000 mg/kg, well above the Pb concentrations measured in the remediated cap. The deer seemed to be ingesting soil or mining waste from one or more small but highly contaminated sources located beyond the remediated cap.

  18. Mechanical behavior of precipitation hardenable steels exposed to highly corrosive environment

    NASA Technical Reports Server (NTRS)

    Rosa, Ferdinand

    1994-01-01

    Unexpected occurrences of failures, due to stress corrosion cracking (SCC) of structural components, indicate a need for improved characterization of materials and more advanced analytical procedures for reliably predicting structures performance. Accordingly, the purpose of this study was to determine the stress corrosion susceptibility of 15 - 5 PH steel over a wide range of applied strain rates in a highly corrosive environment. The selected environment for this investigation was a 3.5 percent NaCl aqueous solution. The material selected for the study was 15 - 5 PH steel in the H 900 condition. The Slow Strain Rate technique was used to test the metallic specimens.

  19. Damage correlations in semiconductor devices exposed to gamma and high energy swift heavy ions

    NASA Astrophysics Data System (ADS)

    Pushpa, N.; Prakash, A. P. Gnana

    2015-05-01

    NPN rf power transistors and N-channel depletion MOSFETs are irradiated by different high energy swift heavy ions and 60Co gamma radiation in the dose range of 100 krad to 100 Mrad. The damage created by different heavy ions and 60Co gamma radiation in NPN rf power transistors and N-channel depletion MOSFETs have been correlated and studied in the same dose range. The recoveries in the electrical characteristics of different swift heavy ions and 60Co gamma irradiated devices have been studied after annihilation.

  20. Damage correlations in semiconductor devices exposed to gamma and high energy swift heavy ions

    SciTech Connect

    Pushpa, N.; Prakash, A. P. Gnana

    2015-05-15

    NPN rf power transistors and N-channel depletion MOSFETs are irradiated by different high energy swift heavy ions and {sup 60}Co gamma radiation in the dose range of 100 krad to 100 Mrad. The damage created by different heavy ions and {sup 60}Co gamma radiation in NPN rf power transistors and N-channel depletion MOSFETs have been correlated and studied in the same dose range. The recoveries in the electrical characteristics of different swift heavy ions and {sup 60}Co gamma irradiated devices have been studied after annihilation.

  1. Optimal group size in a highly social mammal.

    PubMed

    Markham, A Catherine; Gesquiere, Laurence R; Alberts, Susan C; Altmann, Jeanne

    2015-12-01

    Group size is an important trait of social animals, affecting how individuals allocate time and use space, and influencing both an individual's fitness and the collective, cooperative behaviors of the group as a whole. Here we tested predictions motivated by the ecological constraints model of group size, examining the effects of group size on ranging patterns and adult female glucocorticoid (stress hormone) concentrations in five social groups of wild baboons (Papio cynocephalus) over an 11-y period. Strikingly, we found evidence that intermediate-sized groups have energetically optimal space-use strategies; both large and small groups experience ranging disadvantages, in contrast to the commonly reported positive linear relationship between group size and home range area and daily travel distance, which depict a disadvantage only in large groups. Specifically, we observed a U-shaped relationship between group size and home range area, average daily distance traveled, evenness of space use within the home range, and glucocorticoid concentrations. We propose that a likely explanation for these U-shaped patterns is that large, socially dominant groups are constrained by within-group competition, whereas small, socially subordinate groups are constrained by between-group competition and predation pressures. Overall, our results provide testable hypotheses for evaluating group-size constraints in other group-living species, in which the costs of intra- and intergroup competition vary as a function of group size.

  2. Optimal group size in a highly social mammal

    PubMed Central

    Markham, A. Catherine; Gesquiere, Laurence R.; Alberts, Susan C.; Altmann, Jeanne

    2015-01-01

    Group size is an important trait of social animals, affecting how individuals allocate time and use space, and influencing both an individual’s fitness and the collective, cooperative behaviors of the group as a whole. Here we tested predictions motivated by the ecological constraints model of group size, examining the effects of group size on ranging patterns and adult female glucocorticoid (stress hormone) concentrations in five social groups of wild baboons (Papio cynocephalus) over an 11-y period. Strikingly, we found evidence that intermediate-sized groups have energetically optimal space-use strategies; both large and small groups experience ranging disadvantages, in contrast to the commonly reported positive linear relationship between group size and home range area and daily travel distance, which depict a disadvantage only in large groups. Specifically, we observed a U-shaped relationship between group size and home range area, average daily distance traveled, evenness of space use within the home range, and glucocorticoid concentrations. We propose that a likely explanation for these U-shaped patterns is that large, socially dominant groups are constrained by within-group competition, whereas small, socially subordinate groups are constrained by between-group competition and predation pressures. Overall, our results provide testable hypotheses for evaluating group-size constraints in other group-living species, in which the costs of intra- and intergroup competition vary as a function of group size. PMID:26504236

  3. Protective Pleiotropic Effect of Flavonoids on NAD+ Levels in Endothelial Cells Exposed to High Glucose

    PubMed Central

    Boesten, Daniëlle M. P. H. J.; von Ungern-Sternberg, Saskia N. I.; den Hartog, Gertjan J. M.; Bast, Aalt

    2015-01-01

    NAD+ is important for oxidative metabolism by serving as an electron transporter. Hyperglycemia decreases NAD+ levels by activation of the polyol pathway and by overactivation of poly(ADP-ribose)-polymerase (PARP). We examined the protective role of three structurally related flavonoids (rutin, quercetin, and flavone) during high glucose conditions in an in vitro model using human umbilical vein endothelial cells (HUVECs). Additionally we assessed the ability of these flavonoids to inhibit aldose reductase enzyme activity. We have previously shown that flavonoids can inhibit PARP activation. Extending these studies, we here provide evidence that flavonoids are also able to protect endothelial cells against a high glucose induced decrease in NAD+. In addition, we established that flavonoids are able to inhibit aldose reductase, the key enzyme in the polyol pathway. We conclude that this protective effect of flavonoids on NAD+ levels is a combination of the flavonoids ability to inhibit both PARP activation and aldose reductase enzyme activity. This study shows that flavonoids, by a combination of effects, maintain the redox state of the cell during hyperglycemia. This mode of action enables flavonoids to ameliorate diabetic complications. PMID:26180598

  4. Karyotypes of Human Lymphocytes Exposed to High-Energy Iron Ions

    NASA Technical Reports Server (NTRS)

    Durante, M.; George, K.; Wu, H.; Cucinotta, F. A.

    2002-01-01

    Chromosomal aberrations were analyzed using multicolor fluorescence in situ hybridization (mFISH) in human peripheral blood lymphocytes after in vitro exposure to gamma rays or accelerated (56)Fe ions (1 GeV/nucleon, 145 keV/microm) at Brookhaven National Laboratory (Upton, NY). Doses of 0.3 and 3 Gy were used for both radiation types. Chromosomes were prematurely condensed by a phosphatase inhibitor (calyculin A) to avoid the population selection bias observed at metaphase as a result of the severe cell cycle delays induced by heavy ions. A total of 1053 karyotypes (G(2) and M phases) were analyzed in irradiated lymphocytes. Results revealed different distribution patterns for chromosomal aberrations after low- and high-LET radiation exposures: Heavy ions induced a much higher fraction of cells with multiple aberrations, while the majority of the aberrant cells induced by low doses of gamma rays contained a single aberration. The high fraction of complex-type exchanges after heavy ions leads to an overestimation of simple-type asymmetrical interchanges (dicentrics) from analysis of Giemsa-stained samples. However, even after a dose of 3 Gy iron ions, about 30% of the cells presented no complex-type exchanges. The involvement of individual chromosomes in exchanges was similar for densely and sparsely ionizing radiation, and no statistically significant evidence of a nonrandom involvement of specific chromosomes was detected.

  5. High CO2-capture ability of a porous organic polymer bifunctionalized with carboxy and triazole groups.

    PubMed

    Xie, Lin-Hua; Suh, Myunghyun Paik

    2013-08-26

    A new porous organic polymer, SNU-C1, incorporating two different CO2 -attracting groups, namely, carboxy and triazole groups, has been synthesized. By activating SNU-C1 with two different methods, vacuum drying and supercritical-CO2 treatment, the guest-free phases, SNU-C1-va and SNU-C1-sca, respectively, were obtained. Brunauer-Emmett-Teller (BET) surface areas of SNU-C1-va and SNU-C1-sca are 595 and 830 m(2) g(-1), respectively, as estimated by the N2-adsorption isotherms at 77 K. At 298 K and 1 atm, SNU-C1-va and SNU-C1-sca show high CO2 uptakes, 2.31 mmol  g(-1) and 3.14 mmol  g(-1), respectively, the high level being due to the presence of abundant polar groups (carboxy and triazole) exposed on the pore surfaces. Five separation parameters for flue gas and landfill gas in vacuum-swing adsorption were calculated from single-component gas-sorption isotherms by using the ideal adsorbed solution theory (IAST). The data reveal excellent CO2-separation abilities of SNU-C1-va and SNU-C1-sca, namely high CO2-uptake capacity, high selectivity, and high regenerability. The gas-cycling experiments for the materials and the water-treated samples, experiments that involved treating the samples with a CO2-N2 gas mixture (15:85, v/v) followed by a pure N2 purge, further verified the high regenerability and water stability. The results suggest that these materials have great potential applications in CO2 separation.

  6. [Effects of palmitic acid on activity of uncoupling proteins and proton leak in in vitro cerebral mitochondria from the rats exposed to simulated high altitude hypoxia].

    PubMed

    Xu, Yu; Liu, Jun-Ze; Xia, Chen

    2008-02-25

    To reveal the roles of uncoupling proteins (UCPs) in disorder of mitochondrial oxidative phosphorylation induced by free fatty acid during hypoxic exposure, the effects of palmitic acid on activity of UCPs, proton leak and mitochondrial membrane potential in hypoxia-exposed rat brain mitochondria were observed in vitro. Adult Sprague-Dawley (SD) rats were set randomly into control, acute hypoxia and chronic hypoxia groups (n=8 in each group). The acute and chronic hypoxic rats were exposed to simulated 5000 m high altitude in a hypobaric chamber 23 h/d for 3 d and 30 d, respectively. The brain mitochondria were isolated by centrifugation. UCP content and activity were detected by [(3)H]-GTP binding method. The proton leak was measured by TPMP(+) electrode and oxygen electrode. The membrane potential of mitochondria was calculated by detecting the fluorescence from Rodamine 123. Hypoxic exposure resulted in an increase in UCP activity and content as well as proton leak, but a decrease in the membrane potential of rat brain mitochondria. Palmitic acid resulted in further increases in UCP activity and content as well as proton leak, and further decrease in membrane potential of brain mitochondria in vitro from hypoxia-exposed rats, but hypoxic exposure decreased the reactivity of cerebral mitochondria to palmitic acid, especially in the acute hypoxia group. There was a negative correlation between mitochondrial proton leak and K(d) value (representing derivative of UCP activity, P<0.01, r = -0.906), and a positive correlation between proton leak and B(max) (representing the maximal content of UCPs in mitochondrial inner membrane, P<0.01, r = 0.856). Cerebral mitochondrial membrane potential was negatively correlated with proton leak (P<0.01, r = -0.880). It is suggested that hypoxia-induced proton leak enhancement and membrane potential decrease are correlated with the increased activity of UCPs. Hypoxia can also decrease the sensitivity of cerebral mitochondria to

  7. Evaluating the abnormal ossification in tibiotarsi of developing chick embryos exposed to 1.0ppm doses of platinum group metals by spectroscopic techniques.

    PubMed

    Stahler, Adam C; Monahan, Jennifer L; Dagher, Jessica M; Baker, Joshua D; Markopoulos, Marjorie M; Iragena, Diane B; NeJame, Britney M; Slaughter, Robert; Felker, Daniel; Burggraf, Larry W; Isaac, Leon A C; Grossie, David; Gagnon, Zofia E; Sizemore, Ioana E Pavel

    2013-04-01

    Platinum group metals (PGMs), i.e., palladium (Pd), platinum (Pt) and rhodium (Rh), are found at pollutant levels in the environment and are known to accumulate in plant and animal tissues. However, little is known about PGM toxicity. Our previous studies showed that chick embryos exposed to PGM concentrations of 1mL of 5.0ppm (LD50) and higher exhibited severe skeletal deformities. This work hypothesized that 1.0ppm doses of PGMs will negatively impact the mineralization process in tibiotarsi. One milliliter of 1.0ppm of Pd(II), Pt(IV), Rh(III) aqueous salt solutions and a PGM-mixture were injected into the air sac on the 7th and 14th day of incubation. Control groups with no-injection and vehicle injections were included. On the 20th day, embryos were sacrificed to analyze the PGM effects on tibiotarsi using four spectroscopic techniques. 1) Micro-Raman imaging: Hyperspectral Raman data were collected on paraffin embedded cross-sections of tibiotarsi, and processed using in-house-written MATLAB codes. Micro-Raman univariate images that were created from the ν1(PO4(3-)) integrated areas revealed anomalous mineral inclusions within the bone marrow for the PGM-mixture treatment. The age of the mineral crystals (ν(CO3(2-))/ν1(PO4(3-))) was statistically lower for all treatments when compared to controls (p≤0.05). 2) FAAS: The percent calcium content of the chemically digested tibiotarsi in the Pd and Pt groups changed by ~45% with respect to the no-injection control (16.1±0.2%). 3) Micro-XRF imaging: Abnormal calcium and phosphorus inclusions were found within the inner longitudinal sections of tibiotarsi for the PGM-mixture treatment. A clear increase in the mineral content was observed for the outer sections of the Pd treatment. 4) ICP-OES: PGM concentrations in tibiotarsi were undetectable (<5ppb). The spectroscopic techniques gave corroborating results, confirmed the hypothesis, and explained the observed pathological (skeletal developmental abnormalities

  8. Antioxidant responses of Propylaea japonica (Coleoptera: Coccinellidae) exposed to high temperature stress.

    PubMed

    Zhang, Shize; Fu, Wenyan; Li, Ning; Zhang, Fan; Liu, Tong-Xian

    2015-02-01

    Temperature is one of the most important environmental factors, and is responsible for a variety of physiological stress responses in organisms. Induced thermal stress is associated with elevated reactive oxygen species (ROS) generation leading to oxidative damage. The ladybeetle, Propylaea japonica (Thunberg) (Coleoptera: Coccinellidae), is considered a successful natural enemy because of its tolerance to high temperatures in arid and semi-arid areas in China. In this study, we investigated the effect of high temperatures (35, 37, 39, 41 and 43 °C) on the survival and activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidases (POD), glutathione-S-transferases (GST), and total antioxidant capacity (TAC) as well as malondialdehyde (MDA) concentrations in P. japonica adults. The results indicated that P. japonica adults could not survive at 43 °C. CAT, GST and TAC were significantly increased when compared to the control (25 °C), and this played an important role in the process of antioxidant response to thermal stress. SOD and POD activity, as well as MDA, did not differ significantly at 35 and 37 °C compared to the control; however, there were increased levels of SOD, POD and MDA when the temperature was above 37 °C. These results suggest that thermal stress leads to oxidative stress and antioxidant enzymes play important roles in reducing oxidative damage in P. japonica adults. This study represents the first comprehensive report on the antioxidant defense system in predaceous coccinellids (the third trophic level). The findings provide useful information for predicting population dynamics and understanding the potential for P. japonica as a natural enemy to control pest insects under varied environmental conditions. PMID:25614965

  9. Dynamics of liquid films exposed to high-frequency surface vibration.

    PubMed

    Manor, Ofer; Rezk, Amgad R; Friend, James R; Yeo, Leslie Y

    2015-05-01

    We derive a generalized equation that governs the spreading of liquid films under high-frequency (MHz-order) substrate vibration in the form of propagating surface waves and show that this single relationship is universally sufficient to collectively describe the rich and diverse dynamic phenomena recently observed for the transport of oil films under such substrate excitation, in particular, Rayleigh surface acoustic waves. In contrast to low-frequency (Hz- to kHz-order) vibration-induced wetting phenomena, film spreading at such high frequencies arises from convective drift generated by the viscous periodic flow localized in a region characterized by the viscous penetration depth β(-1)≡(2μ/ρω)(1/2) adjacent to the substrate that is invoked directly by its vibration; μ and ρ are the viscosity and the density of the liquid, respectively, and ω is the excitation frequency. This convective drift is responsible for driving the spreading of thin films of thickness h≪k(l)(-1), which spread self-similarly as t(1/4) along the direction of the drift corresponding to the propagation direction of the surface wave, k(l) being the wave number of the compressional acoustic wave that forms in the liquid due to leakage of the surface wave energy from the substrate into the liquid and t the time. Films of greater thicknesses h∼k(l)(-1)≫β(-1), in contrast, are observed to spread with constant velocity but in a direction that opposes the drift and surface wave propagation due to the attenuation of the acoustic wave in the liquid. The universal equation derived allows for the collective prediction of the spreading of these thin and thick films in opposing directions. PMID:26066257

  10. High Resolution STEM-EELS Study of Silver Nanoparticles Exposed to Light and Humic Substances.

    PubMed

    Römer, Isabella; Wang, Zhi Wei; Merrifield, Ruth C; Palmer, Richard E; Lead, Jamie

    2016-03-01

    Nanoparticles (NPs) are defined as particles with at least one dimension between 1 and 100 nm or with properties that differ from their bulk material, which possess unique properties. The extensive use of NPs means that discharge to the environment is likely increasing, but fate, behavior, and effects under environmentally relevant conditions are insufficiently studied. This paper focuses on the transformations of silver nanoparticles (AgNPs) under simulated but realistic environmental conditions. High resolution aberration-corrected scanning transmission electron microscopy (HAADF STEM) coupled with electron energy loss spectroscopy (EELS) and UV-vis were used within a multimethod approach to study morphology, surface chemistry transformations, and corona formation. Although loss, most likely by dissolution, was observed, there was no direct evidence of oxidation from the STEM-EELS. However, in the presence of fulvic acid (FA), a 1.3 nm oxygen-containing corona was observed around the AgNPs in water; modeled data based on the HAADF signal at near atomic resolution suggest this was an FA corona was formed and was not silver oxide, which was coherent (i.e., fully coated in FA), where observed. The corona further colloidally stabilized the NPs for periods of weeks to months, dependent on the solution conditions. PMID:26792384

  11. Detecting cavitation in mercury exposed to a high-energy pulsed proton beam

    SciTech Connect

    Manzi, Nicholas J; Chitnis, Parag V; Holt, Ray G; Roy, Ronald A; Cleveland, Robin O; Riemer, Bernie; Wendel, Mark W

    2010-01-01

    The Oak Ridge National Laboratory Spallation Neutron Source employs a high-energy pulsed proton beam incident on a mercury target to generate short bursts of neutrons. Absorption of the proton beam produces rapid heating of the mercury, resulting in the formation of acoustic shock waves and the nucleation of cavitation bubbles. The subsequent collapse of these cavitation bubbles promote erosion of the steel target walls. Preliminary measurements using two passive cavitation detectors (megahertz-frequency focused and unfocused piezoelectric transducers) installed in a mercury test target to monitor cavitation generated by proton beams with charges ranging from 0.041 to 4.1 C will be reported on. Cavitation was initially detected for a beam charge of 0.082 C by the presence of an acoustic emission approximately 250 s after arrival of the incident proton beam. This emission was consistent with an inertial cavitation collapse of a bubble with an estimated maximum bubble radius of 0.19 mm, based on collapse time. The peak pressure in the mercury for the initiation of cavitation was predicted to be 0.6 MPa. For a beam charge of 0.41 C and higher, the lifetimes of the bubbles exceeded the reverberation time of the chamber (~300 s), and distinct windows of cavitation activity were detected, a phenomenon that likely resulted from the interaction of the reverberation in the chamber and the cavitation bubbles.

  12. Magnetotropism of roots and structure of their statocytes exposed to high gradient magnetic field

    NASA Astrophysics Data System (ADS)

    Belyavskaya, N. A.; Polishchuk, O. V.; Kondrachuk, A. V.

    In most living organisms gravity perception is based on the response of the gravisensing system to displacement of specific mass induced by a gravitational force The amyloplasts in higher plants are known to play the important role as the specific mass in gravisensing cells As was shown by Kuznetsov Hasenstein 1996 the high-gradient magnetic field HGMF exerts a directional ponderomotive force on such diamagnetic structures as amyloplasts This effect of the HGMF results in root curvature similar to that produced by gravity It was suggested that the HGMF could allow to imitate the effects of gravity in microgravity and or to change them in laboratory conditions correspondingly as well as to study statolith-related processes in graviperception Therefore the correlation between the direction of the ponderomotive force resulting in statolith displacements and the direction of the HGMF-induced plant curvature can be the serious argument to support this suggestion and needs the detailed structural analysis We have designed the HGMF facility that allows for generating the HGMF and analyzing its effects on higher plants roots The parameters of kinetics of Lepidium sativum L and Pisum sativum L root curvatures under both the HGMF action and gravistimulation were recorded by video system and measured by means of image analysis software The main results of the study are followings 1 the magnetotropic effect of the HGMF on root growth was found for pea and cress roots 2 the critical value of ponderomotive force that

  13. Identification of highly reactive cysteine residues at less exposed positions in the Fab constant region for site-specific conjugation.

    PubMed

    Shiraishi, Yasuhisa; Muramoto, Takashige; Nagatomo, Kazutaka; Shinmi, Daisuke; Honma, Emiko; Masuda, Kazuhiro; Yamasaki, Motoo

    2015-06-17

    Engineered cysteine residues are currently used for the site-specific conjugation of antibody-drug conjugates (ADC). In general, positions on the protein surface have been selected for substituting a cysteine as a conjugation site; however, less exposed positions (with less than 20% of accessible surface area [ASA]) have not yet been evaluated. In this study, we engineered original cysteine positional variants of a Fab fragment, with less than 20% of ASA, and evaluated their thiol reactivities through conjugation with various kinds of payloads. As a result, we have identified three original cysteine positional variants (heavy chain: Hc-A140C, light chain: Lc-Q124C and Lc-L201C), which exhibited similar monomer content, thermal stability, and antigen binding affinity in comparison to the wild-type Fab. In addition, the presence of cysteine in these positions made it possible for the Fab variants to react with variable-sized molecules with high efficiency. The favorable physical properties of the cysteine positional variants selected in our study suggest that less exposed positions, with less than 20% of ASA, provide an alternative for creating conjugation sites.

  14. Resilience of a High Latitude Red Sea Frining Corals Exposed to Extreme Temperatures

    NASA Astrophysics Data System (ADS)

    Moustafa, M.; Moustafa, M. S.; Moustafa, S.; Moustafa, Z. D.

    2013-05-01

    , while minimum daily means at Ein Sokhna were almost equal to those at Ismailia (200 km north). These trends were opposite to what was expected considering each stations geographical locations. The unexpected temperature trends, the daily/half daily dominant frequencies, and the short distance between the mountain range and Zaki's Reef vs. Hurghada (0.5 vs. 35 km), prompted us to hypothesize that a Foehn wind may be responsible for the high air temperatures observed at Ein Sokhna. We applied NOAA's HYSPLIT model to explore local circulation patterns, which suggest that the high mountain range blocks the year-round trade wind and forces it to climb up the western slope, where it loses moisture and reduces its temperature. As this cool, denser air reaches the mountain top, the air parcel starts rolling down the eastern slopes, which causes air temperature to rise and result in an increase in local air temperatures. These warmer than normal air temperatures measured here may aid in securing these northernmost reefs survival. Further scrutiny of the mechanisms by which area reefs are able to thrive extreme environmental conditions continues to be investigated.

  15. Economy of locomotion in high-altitude Tibetan migrants exposed to normoxia

    PubMed Central

    Marconi, Claudio; Marzorati, Mauro; Sciuto, Daniele; Ferri, Alessandra; Cerretelli, Paolo

    2005-01-01

    High-altitude Tibetans undergo a pattern of adaptations to chronic hypoxia characterized, among others, by a more efficient aerobic performance compared with acclimatized lowlanders. To test whether such changes may persist upon descent to moderate altitude, oxygen uptake of 17 male Tibetan natives lifelong residents at 3500–4500 m was assessed within 1 month upon migration to 1300 m. Exercise protocols were: 5 min treadmill walking at 6 km h−1 on increasing inclines from +5 to +15% and 5 min running at 10 km h−1 on a +5% grade. The data (mean ± s.e.m.) were compared with those obtained on Nepali lowlanders. When walking on +10, +12.5 and +15% inclines, net of Tibetans was 25.2 ± 0.7, 29.1 ± 1.1 and 31.3 ± 0.9 ml kg−1 min−1, respectively, i.e. 8, 10 and 13% less (P < 0.05) than that of Nepali. At the end of the heaviest load, blood lactate concentration was lower in Tibetans than in Nepali (6.0 ± 0.9 versus 8.9 ± 0.6 mm; P < 0.05). During running, of Tibetans was 35.1 ± 0.8 versus 39.3 ± 0.7 ml kg−1 min−1 (i.e. 11% less; P < 0.01). In conclusion, during submaximal walking and running at 1300 m, Tibetans are still characterized by lower aerobic energy expenditure than control subjects that is not accounted for by differences in mechanical power output and/or compensated for by anaerobic glycolysis. These findings indicate that chronic hypoxia induces metabolic adaptations whose underlying mechanisms still need to be elucidated, that persist for at least 1 month upon descent to moderate altitude. PMID:16179365

  16. Direct Measurement of Perchlorate Exposure Biomarkers in a Highly Exposed Population: A Pilot Study

    PubMed Central

    Wong, Michelle; Copan, Lori; Olmedo, Luis; Patton, Sharyle; Haas, Robert; Atencio, Ryan; Xu, Juhua; Valentin-Blasini, Liza

    2011-01-01

    Exposure to perchlorate is ubiquitous in the United States and has been found to be widespread in food and drinking water. People living in the lower Colorado River region may have perchlorate exposure because of perchlorate in ground water and locally-grown produce. Relatively high doses of perchlorate can inhibit iodine uptake and impair thyroid function, and thus could impair neurological development in utero. We examined human exposures to perchlorate in the Imperial Valley among individuals consuming locally grown produce and compared perchlorate exposure doses to state and federal reference doses. We collected 24-hour urine specimen from a convenience sample of 31 individuals and measured urinary excretion rates of perchlorate, thiocyanate, nitrate, and iodide. In addition, drinking water and local produce were also sampled for perchlorate. All but two of the water samples tested negative for perchlorate. Perchlorate levels in 79 produce samples ranged from non-detect to 1816 ppb. Estimated perchlorate doses ranged from 0.02 to 0.51 µg/kg of body weight/day. Perchlorate dose increased with the number of servings of dairy products consumed and with estimated perchlorate levels in produce consumed. The geometric mean perchlorate dose was 70% higher than for the NHANES reference population. Our sample of 31 Imperial Valley residents had higher perchlorate dose levels compared with national reference ranges. Although none of our exposure estimates exceeded the U. S. EPA reference dose, three participants exceeded the acceptable daily dose as defined by bench mark dose methods used by the California Office of Environmental Health Hazard Assessment. PMID:21394205

  17. Direct measurement of perchlorate exposure biomarkers in a highly exposed population: a pilot study.

    PubMed

    English, Paul; Blount, Ben; Wong, Michelle; Copan, Lori; Olmedo, Luis; Patton, Sharyle; Haas, Robert; Atencio, Ryan; Xu, Juhua; Valentin-Blasini, Liza

    2011-03-04

    Exposure to perchlorate is ubiquitous in the United States and has been found to be widespread in food and drinking water. People living in the lower Colorado River region may have perchlorate exposure because of perchlorate in ground water and locally-grown produce. Relatively high doses of perchlorate can inhibit iodine uptake and impair thyroid function, and thus could impair neurological development in utero. We examined human exposures to perchlorate in the Imperial Valley among individuals consuming locally grown produce and compared perchlorate exposure doses to state and federal reference doses. We collected 24-hour urine specimen from a convenience sample of 31 individuals and measured urinary excretion rates of perchlorate, thiocyanate, nitrate, and iodide. In addition, drinking water and local produce were also sampled for perchlorate. All but two of the water samples tested negative for perchlorate. Perchlorate levels in 79 produce samples ranged from non-detect to 1816 ppb. Estimated perchlorate doses ranged from 0.02 to 0.51 µg/kg of body weight/day. Perchlorate dose increased with the number of servings of dairy products consumed and with estimated perchlorate levels in produce consumed. The geometric mean perchlorate dose was 70% higher than for the NHANES reference population. Our sample of 31 Imperial Valley residents had higher perchlorate dose levels compared with national reference ranges. Although none of our exposure estimates exceeded the U. S. EPA reference dose, three participants exceeded the acceptable daily dose as defined by bench mark dose methods used by the California Office of Environmental Health Hazard Assessment.

  18. Direct measurement of perchlorate exposure biomarkers in a highly exposed population: a pilot study.

    PubMed

    English, Paul; Blount, Ben; Wong, Michelle; Copan, Lori; Olmedo, Luis; Patton, Sharyle; Haas, Robert; Atencio, Ryan; Xu, Juhua; Valentin-Blasini, Liza

    2011-01-01

    Exposure to perchlorate is ubiquitous in the United States and has been found to be widespread in food and drinking water. People living in the lower Colorado River region may have perchlorate exposure because of perchlorate in ground water and locally-grown produce. Relatively high doses of perchlorate can inhibit iodine uptake and impair thyroid function, and thus could impair neurological development in utero. We examined human exposures to perchlorate in the Imperial Valley among individuals consuming locally grown produce and compared perchlorate exposure doses to state and federal reference doses. We collected 24-hour urine specimen from a convenience sample of 31 individuals and measured urinary excretion rates of perchlorate, thiocyanate, nitrate, and iodide. In addition, drinking water and local produce were also sampled for perchlorate. All but two of the water samples tested negative for perchlorate. Perchlorate levels in 79 produce samples ranged from non-detect to 1816 ppb. Estimated perchlorate doses ranged from 0.02 to 0.51 µg/kg of body weight/day. Perchlorate dose increased with the number of servings of dairy products consumed and with estimated perchlorate levels in produce consumed. The geometric mean perchlorate dose was 70% higher than for the NHANES reference population. Our sample of 31 Imperial Valley residents had higher perchlorate dose levels compared with national reference ranges. Although none of our exposure estimates exceeded the U. S. EPA reference dose, three participants exceeded the acceptable daily dose as defined by bench mark dose methods used by the California Office of Environmental Health Hazard Assessment. PMID:21394205

  19. Laboratory Analysis Of Water, Hydrocarbon And Ammonia Ice Mixtures Exposed To High-energy Electron Irradiation

    NASA Astrophysics Data System (ADS)

    Hand, Kevin P.; Carlson, R. W.; Tsapin, A. I.

    2006-09-01

    Irradiation of low temperature ices in the laboratory provides insight into processes that may be occurring on icy bodies in the solar system. Here we report on results from high-energy (10keV) electron irradiation of thin ice films at 1e-8 torr and 70-120K. Mixtures include water with CO2, C3H8, C3H6, C4H10 (butane and isobutane), C4H8,(1-butene and cis/trans-2-butene), and NH3. During irradiation of H2O + alkane films at 80K, CO2 and CH4 production is observed and both species are retained in the ice, possibly trapped in clathrates. The -CH3 infrared bands initially present are seen to decrease with increasing dose. Bands associated with -CH2- persist, indicating polymerization of the initial short-chain hydrocarbons. In alkenes a similar evolution toward polymerization is observed, however the first step appears to be the destruction of the C=C bond. Upon warming of the film, mass spectra data compliment the mid-infrared data and indicate the production of H2CO, however glycolic acid is not explicitly seen in the mass spectra. When warmed to 300K, residues remained for all irradiated films except that of the H2O + CO2 mixtures. Residues were analyzed with Matrix Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI). Results show the production of large aliphatic, very refractory, hydrocarbons (with m/z up to 2500). Mid-infrared spectra of the residues indicate carbonyls and alcohols, likely due to polymerized aldehydes and carboxylic acids. Films of H2O + C3H8 + NH3 at 70K show the production of OCN- (cyanate ion), formamide, along with other possible amides and hydrocarbons. HPLC results indicate the production of racemic alanine. Finally, results of abiotic experiments are compared to results from the irradiation of bacterial spores in ice. The application to Europa and Enceladus is discussed.

  20. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to High and Low LET Radiations

    NASA Technical Reports Server (NTRS)

    Hada, M.; Wilkins, R.; Saganti, P. B.; Gersey, B.; Cucinotta, F. A.; Wu, H.

    2006-01-01

    Energetic heavy ions pose a health risk to astronauts in extended ISS and future Mars missions. High-LET heavy ions are particularly effective in causing various biological effects including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human epithelial cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells (CH184B5F5/M10) were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory, high energy neutron at the Los Alamos Nuclear Science Center (LANSCE) or Cs-137-gamma radiation source at the University of Texas, MD Anderson Cancer Center. After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The results of the mBAND study showed a higher ratio of inversion involved with interchromosomal exchange in heavy ions compared to -ray irradiation. Analysis of chromosome aberrations using mBAND has the potential to provide useful information on human cell response to space-like radiation.

  1. Cytoplasmic translocation of high-mobility group box-1 protein is induced by diabetes and high glucose in retinal pericytes

    PubMed Central

    Kim, Junghyun; Kim, Chan-Sik; Sohn, Eunjin; Kim, Jin Sook

    2016-01-01

    The aim of the present study was to assess the involvement of the high-mobility group box-1 (HMGB1) protein, receptor for advanced glycation end products (RAGE) and nuclear factor (NF)-κB signaling pathway in the development of diabetic retinopathy. Rat primary retinal pericytes were exposed to 25 mmol/l D-glucose for 48 h. Diabetic retinal vessels were prepared from streptozotocin-induced diabetic rats 12 weeks following the induction of diabetes. The expression of HMGB1 was detected using immunofluorescence staining. The expression of RAGE and the activity of NF-κB were analyzed using western blot and electrophoretic mobility shift assays, respectively. The results showed that HMGB1 was translocated to the cytoplasm of the high glucose-treated pericytes and diabetic retinal pericytes, whereas, in the control cells and the normal retinas, HMGB1 was expressed in the cell nuclei only. The expression of RAGE, a potential receptor for HMGB1, and the activity of NF-κB were also increased in the high glucose-treated pericytes, compared with the normal control cells. In addition, high glucose increased the binding of NF-κB to the RAGE promoter. These findings suggested that the cytoplasmic translocation of HMGB1 may be caused by diabetes and high glucose in retinal pericytes, and that the pathogenic role of HMGB1 may be dependent on the expression of RAGE and activation of NF-κB. PMID:27599553

  2. Cytoplasmic translocation of high-mobility group box-1 protein is induced by diabetes and high glucose in retinal pericytes.

    PubMed

    Kim, Junghyun; Kim, Chan-Sik; Sohn, Eunjin; Kim, Jin Sook

    2016-10-01

    The aim of the present study was to assess the involvement of the high-mobility group box-1 (HMGB1) protein, receptor for advanced glycation end products (RAGE) and nuclear factor (NF)-κB signaling pathway in the development of diabetic retinopathy. Rat primary retinal pericytes were exposed to 25 mmol/l D‑glucose for 48 h. Diabetic retinal vessels were prepared from streptozotocin-induced diabetic rats 12 weeks following the induction of diabetes. The expression of HMGB1 was detected using immunofluorescence staining. The expression of RAGE and the activity of NF‑κB were analyzed using western blot and electrophoretic mobility shift assays, respectively. The results showed that HMGB1 was translocated to the cytoplasm of the high glucose‑treated pericytes and diabetic retinal pericytes, whereas, in the control cells and the normal retinas, HMGB1 was expressed in the cell nuclei only. The expression of RAGE, a potential receptor for HMGB1, and the activity of NF‑κB were also increased in the high glucose‑treated pericytes, compared with the normal control cells. In addition, high glucose increased the binding of NF‑κB to the RAGE promoter. These findings suggested that the cytoplasmic translocation of HMGB1 may be caused by diabetes and high glucose in retinal pericytes, and that the pathogenic role of HMGB1 may be dependent on the expression of RAGE and activation of NF‑κB. PMID:27599553

  3. Biofluid metabotyping of occupationally exposed subjects to air pollution demonstrates high oxidative stress and deregulated amino acid metabolism

    PubMed Central

    Pradhan, Surya Narayan; Das, Aleena; Meena, Ramovatar; Nanda, Ranjan Kumar; Rajamani, Paulraj

    2016-01-01

    Occupational exposure to air pollution induces oxidative stress and prolonged exposure increases susceptibility to cardiovascular and respiratory diseases in several working groups. Biofluid of these subjects may reflect perturbed metabolic phenotypes. In this study we carried out a comparative molecular profiling study using parallel biofluids collected from subjects (n = 85) belonging to auto rickshaw drivers (ARD), traffic cops (TC) and office workers (OW). Higher levels of oxidative stress and inflammation markers in serum of ARD subjects were observed as compared to OW and TC. Uni and multivariate analyses of metabolites identified in urine by 1H NMR revealed 11 deregulated molecules in ARD subjects and involved in phenylalanine, histidine, arginine and proline metabolism. Despite contribution of confounding factors like exposure period, dietary factors including smoking and alcohol status, our results demonstrate existence of exposure specific metabotypes in biofluids of ARD, OW and TC groups. Monitoring serum oxidative stress and inflammation markers and urine metabolites by NMR may be useful to characterize perturbed metabolic phenotypes in populations exposed to urban traffic air pollution. PMID:27767182

  4. Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Final Report

    SciTech Connect

    Hardage, Bob A.; DeAngelo, Michael V.; Ermolaeva, Elena; Hardage, Bob A.; Remington, Randy; Sava, Diana; Wagner, Donald; Wei, Shuijion

    2013-02-01

    The objective of our research was to develop and demonstrate seismic data-acquisition and data-processing technologies that allow geothermal prospects below high-velocity rock outcrops to be evaluated. To do this, we acquired a 3-component seismic test line across an area of exposed high-velocity rocks in Brewster County, Texas, where there is high heat flow and surface conditions mimic those found at numerous geothermal prospects. Seismic contractors have not succeeded in creating good-quality seismic data in this area for companies who have acquired data for oil and gas exploitation purposes. Our test profile traversed an area where high-velocity rocks and low-velocity sediment were exposed on the surface in alternating patterns that repeated along the test line. We verified that these surface conditions cause non-ending reverberations of Love waves, Rayleigh waves, and shallow critical refractions to travel across the earth surface between the boundaries of the fast-velocity and slow-velocity material exposed on the surface. These reverberating surface waves form the high level of noise in this area that does not allow reflections from deep interfaces to be seen and utilized. Our data-acquisition method of deploying a box array of closely spaced geophones allowed us to recognize and evaluate these surface-wave noise modes regardless of the azimuth direction to the surface anomaly that backscattered the waves and caused them to return to the test-line profile. With this knowledge of the surface-wave noise, we were able to process these test-line data to create P-P and SH-SH images that were superior to those produced by a skilled seismic data-processing contractor. Compared to the P-P data acquired along the test line, the SH-SH data provided a better detection of faults and could be used to trace these faults upward to the boundaries of exposed surface rocks. We expanded our comparison of the relative value of S-wave and P-wave seismic data for geothermal

  5. Humoral immunity in tuberculin skin test anergy and its role in high-risk persons exposed to active tuberculosis.

    PubMed

    Encinales, Liliana; Zuñiga, Joaquin; Granados-Montiel, Julio; Yunis, Maria; Granados, Julio; Almeciga, Ingrid; Clavijo, Olga; Awad, Carlos; Collazos, Vilma; Vargas-Rojas, María Inés; Bañales-Mendez, José Luis; Vazquez-Castañeda, Lilia; Stern, Joel N; Romero, Viviana; Fridkis-Hareli, Masha; Frindkis-Hareli, Masha; Terreros, Daniel; Fernandez-Viña, Marcelo; Yunis, Edmond J

    2010-02-01

    The most common test to identify latent tuberculosis is the tuberculin skin test that detects T cell responses of delayed type hypersensitivity type IV. Since it produces false negative reactions in active tuberculosis or in high-risk persons exposed to tuberculosis patients as shown in this report, we studied antibody profiles to explain the anergy of such responses in high-risk individuals without active infection. Our results showed that humoral immunity against tuberculin, regardless of the result of the tuberculin skin test is important for protection from active tuberculosis and that the presence of high antibody titers is a more reliable indicator of infection latency suggesting that latency can be based on the levels of antibodies together with in vitro proliferation of peripheral blood mononuclear cells in the presence of the purified protein derivative. Importantly, anti-tuberculin IgG antibody levels mediate the anergy described herein, which could also prevent reactivation of disease in high-risk individuals with high antibody titers. Such anti-tuberculin IgG antibodies were also found associated with blocking and/or stimulation of in vitro cultures of PBMC with tuberculin. In this regard, future studies need to establish if immune responses to Mycobacterium tuberculosis can generate a broad spectrum of reactions either toward Th1 responses favoring stimulation by cytokines or by antibodies and those toward diminished responses by Th2 cytokines or blocking by antibodies; possibly involving mechanisms of antibody dependent protection from Mtb by different subclasses of IgG.

  6. The treatment with the probiotic Shewanella putrefaciens Pdp11 of specimens of Solea senegalensis exposed to high stocking densities to enhance their resistance to disease.

    PubMed

    Tapia-Paniagua, S T; Vidal, S; Lobo, C; Prieto-Álamo, M J; Jurado, J; Cordero, H; Cerezuela, R; García de la Banda, I; Esteban, M A; Balebona, M C; Moriñigo, M A

    2014-12-01

    Aquaculture industry exposes fish to acute stress events, such as high stocking density, and a link between stress and higher susceptibility to diseases has been concluded. Several studies have demonstrated increased stress tolerance of fish treated with probiotics, but the mechanisms involved have not been elucidated. Shewanella putrefaciens Pdp11 is a strain isolated from healthy gilthead seabream (Sparus aurata L.) and it is considered as probiotics. The aim of this study was to evaluate the effect of the dietary administration of this probiotics on the stress tolerance of Solea senegalensis specimens farmed under high stocking density (PHD) compared to a group fed a commercial diet and farmed under the same conditions (CHD). In addition, during the experiment, a natural infectious outbreak due to Vibrio species affected fish farmed under crowding conditions. Changes in the microbiota and histology of intestine and in the transcription of immune response genes were evaluated at 19 and 30 days of the experiment. Mortality was observed after 9 days of the beginning of the experiment in CHD and PHD groups, it being higher in the CHD group. Fish farmed under crowding stress showed reduced expression of genes at 19 day probiotic feeding. On the contrary, a significant increase in immune related gene expression was detected in CHD fish at 30 day, whereas the gene expression in fish from PHD group was very similar to that showed in specimens fed and farmed with the conventional conditions. In addition, the dietary administration of S. putrefaciens Pdp11 produced an important modulation of the intestinal microbiota, which was significantly correlated with the high number of goblet cells detected in fish fed the probiotic diet. PMID:25149590

  7. Thermal behavior and temperature measurements of melting beryllium plasma-facing components exposed to high heat flux

    NASA Astrophysics Data System (ADS)

    Gauthier, E.; Pocheau, C.; Kovari, M.; Barnard, J. M.; Crowley, B.; Godwin, J.; Lane, C.

    2015-08-01

    The emissivity of metallic materials is low and varies with temperature and wavelength inducing errors on surface temperature measurements. High heat flux experiments on beryllium were carried out to investigate the thermal behavior of bulk Be tiles. Thermal modeling aiming at determining the surface and bulk temperatures have been performed using ANSYS®. A Be tile was exposed to heat flux with power density ranging between 1 and 7 MW/m2. Surface temperatures were measured using an infrared camera in the 3-5 μm range and two-color pyrometers, one at short wavelengths (1.5-1.7 μm) and one at mid IR range wavelengths (2-4 μm) range. Both the IR camera and two-color pyrometers do not provide accurate temperature measurements on melted Be due to changes in the emissivities and emissivity ratio induced by surface modifications.

  8. Sunflower exposed to high-intensity microwave-frequency electromagnetic field: electrophysiological response requires a mechanical injury to initiate.

    PubMed

    Roux, David; Catrain, Alexandre; Lallechere, Sébastien; Joly, Jean-Christophe

    2015-01-01

    We have monitored the electrical potential variations (EPV) of sunflower plants illuminated by a high-intensity microwave-frequency (2.5 GHz, 1.5 kV/m) electromagnetic field (EMF). We have designed an appropriate set-up that allows parallel temperature and EPV measurements while part of the plant is being exposed to the field. The results show that the considered EMF does not induce plant EPV directly. This electrophysiological response appears only when the EMF leads to a mechanical injury of the tissues via a thermal effect (dielectric heating). Once the plant inner temperature reached a threshold, we systematically observed burn-like lesions associated with the bending of the stem or leaf-stalks. Theses mechanical constraints were rapidly followed by EPVs, moving through the stem.

  9. High interindividual variability in dose-dependent reduction in speed of movement after exposing C. elegans to shock waves.

    PubMed

    Angstman, Nicholas B; Kiessling, Maren C; Frank, Hans-Georg; Schmitz, Christoph

    2015-01-01

    In blast-related mild traumatic brain injury (br-mTBI) little is known about the connections between initial trauma and expression of individual clinical symptoms. Partly due to limitations of current in vitro and in vivo models of br-mTBI, reliable prediction of individual short- and long-term symptoms based on known blast input has not yet been possible. Here we demonstrate a dose-dependent effect of shock wave exposure on C. elegans using shock waves that share physical characteristics with those hypothesized to induce br-mTBI in humans. Increased exposure to shock waves resulted in decreased mean speed of movement while increasing the proportion of worms rendered paralyzed. Recovery of these two behavioral symptoms was observed during increasing post-traumatic waiting periods. Although effects were observed on a population-wide basis, large interindividual variability was present between organisms exposed to the same highly controlled conditions. Reduction of cavitation by exposing worms to shock waves in polyvinyl alcohol resulted in reduced effect, implicating primary blast effects as damaging components in shock wave induced trauma. Growing worms on NGM agar plates led to the same general results in initial shock wave effect in a standard medium, namely dose-dependence and high interindividual variability, as raising worms in liquid cultures. Taken together, these data indicate that reliable prediction of individual clinical symptoms based on known blast input as well as drawing conclusions on blast input from individual clinical symptoms is not feasible in br-mTBI. PMID:25705183

  10. High interindividual variability in dose-dependent reduction in speed of movement after exposing C. elegans to shock waves

    PubMed Central

    Angstman, Nicholas B.; Kiessling, Maren C.; Frank, Hans-Georg; Schmitz, Christoph

    2015-01-01

    In blast-related mild traumatic brain injury (br-mTBI) little is known about the connections between initial trauma and expression of individual clinical symptoms. Partly due to limitations of current in vitro and in vivo models of br-mTBI, reliable prediction of individual short- and long-term symptoms based on known blast input has not yet been possible. Here we demonstrate a dose-dependent effect of shock wave exposure on C. elegans using shock waves that share physical characteristics with those hypothesized to induce br-mTBI in humans. Increased exposure to shock waves resulted in decreased mean speed of movement while increasing the proportion of worms rendered paralyzed. Recovery of these two behavioral symptoms was observed during increasing post-traumatic waiting periods. Although effects were observed on a population-wide basis, large interindividual variability was present between organisms exposed to the same highly controlled conditions. Reduction of cavitation by exposing worms to shock waves in polyvinyl alcohol resulted in reduced effect, implicating primary blast effects as damaging components in shock wave induced trauma. Growing worms on NGM agar plates led to the same general results in initial shock wave effect in a standard medium, namely dose-dependence and high interindividual variability, as raising worms in liquid cultures. Taken together, these data indicate that reliable prediction of individual clinical symptoms based on known blast input as well as drawing conclusions on blast input from individual clinical symptoms is not feasible in br-mTBI. PMID:25705183

  11. High-mobility group box-1 in sterile inflammation.

    PubMed

    Tsung, A; Tohme, S; Billiar, T R

    2014-11-01

    High-mobility group box 1 (HMGB1) was originally defined as a ubiquitous nuclear protein, but it was later determined that the protein has different roles both inside and outside of cells. Nuclear HMGB1 regulates chromatin structure and gene transcription, whereas cytosolic HMGB1 is involved in inflammasome activation and autophagy. Extracellular HMGB1 has drawn attention because it can bind to related cell signalling transduction receptors, such as the receptor for advanced glycation end products, Toll-like receptor (TLR)2, TLR4 and TLR9. It also participates in the development and progression of a variety of diseases. HMGB1 is actively secreted by stimulation of the innate immune system, and it is passively released by ischaemia or cell injury. This review focuses on the important role of HMGB1 in the pathogenesis of acute and chronic sterile inflammatory conditions. Strategies that target HMGB1 have been shown to significantly decrease inflammation in several disease models of sterile inflammation, and this may represent a promising clinical approach for treatment of certain conditions associated with sterile inflammation. PMID:24935761

  12. High-Mobility Group Box 1, Oxidative Stress, and Disease

    PubMed Central

    Kang, Rui; Zeh, Herbert J.

    2011-01-01

    Abstract Oxidative stress and associated reactive oxygen species can modify lipids, proteins, carbohydrates, and nucleic acids, and induce the mitochondrial permeability transition, providing a signal leading to the induction of autophagy, apoptosis, and necrosis. High-mobility group box 1 (HMGB1) protein, a chromatin-binding nuclear protein and damage-associated molecular pattern molecule, is integral to oxidative stress and downstream apoptosis or survival. Accumulation of HMGB1 at sites of oxidative DNA damage can lead to repair of the DNA. As a redox-sensitive protein, HMGB1 contains three cysteines (Cys23, 45, and 106). In the setting of oxidative stress, it can form a Cys23-Cys45 disulfide bond; a role for oxidative homo- or heterodimerization through the Cys106 has been suggested for some of its biologic activities. HMGB1 causes activation of nicotinamide adenine dinucleotide phosphate oxidase and increased reactive oxygen species production in neutrophils. Reduced and oxidized HMGB1 have different roles in extracellular signaling and regulation of immune responses, mediated by signaling through the receptor for advanced glycation end products and/or Toll-like receptors. Antioxidants such as ethyl pyruvate, quercetin, green tea, N-acetylcysteine, and curcumin are protective in the setting of experimental infection/sepsis and injury including ischemia-reperfusion, partly through attenuating HMGB1 release and systemic accumulation. Antioxid. Redox Signal. 14, 1315–1335. PMID:20969478

  13. Indiana University High Energy Physics Group, Task C

    SciTech Connect

    Heinz, R.M.; Mufson, S.L.; Musser, J.

    1991-01-01

    The Indiana University High Energy Physics Group, Task C has been actively involved in the MACRO experiment at Gran Sasso and the SSC experiment L during the current contract year. MACRO is a large US-Italian Monopole, Astrophysics, and Cosmic Ray Observatory being built under the Gran Sasso Mountain outside of Rome. Indiana University is in charge of organizing the United States software effort. We have built a state-of-the-art two-meter spectrophotometer for the MACRO liquid scintillator. We are in charge of ERP, the Event Reconstruction Processor online trigger processor for muons and stellar collapse. We are designing an air Cerenkov array to be placed on top of the Gran Sasso. Our other activity involves participation in the SSC experiment L. As long-standing members of L we have done proposal writing and have worked on important L planning and organization matters. We are now doing development work on the L Central Tracker straw drift tubes, including gas optimization, readout, and Monte Carlos. 12 refs., 20 figs., 1 tab.

  14. Contribution of Direct and Indirect Exposure to Human Serum Concentrations of Perfluorooctanoic Acid in an Occupationally Exposed Group of Ski Waxers.

    PubMed

    Gomis, Melissa I; Vestergren, Robin; Nilsson, Helena; Cousins, Ian T

    2016-07-01

    The contribution of direct (i.e., uptake of perfluorooctanoic acid (PFOA) itself) and indirect (i.e., uptake of 8:2 fluorotelomer alcohol (FTOH) and metabolism to PFOA) exposure to PFOA serum concentrations was investigated using a dynamic one-compartment pharmacokinetic (PK) model. The PK model was applied to six occupationally exposed ski waxers for whom direct and indirect exposures via inhalation were characterized using multiple measurements with personal air sampling devices. The model was able to predict the diverging individual temporal trends of PFOA in serum with correlation coefficients of 0.82-0.94. For the four technicians with high initial concentrations of PFOA in serum (250-1050 ng/mL), the ongoing occupational exposure (both direct and indirect) was of minor importance and net depuration of PFOA was observed throughout the ski season. An estimated average intrinsic elimination half-life of 2.4 years (1.8-3.1 years accounting for variation between technicians and model uncertainty) was derived for these technicians. The remaining two technicians, who had much lower initial serum concentrations (10-17 ng/mL), were strongly influenced by exposure during the ski season with indirect exposure contributing to 45% of PFOA serum concentrations. On the basis of these model simulations, an average metabolism yield of 0.003 (molar concentration basis; uncertainty range of 0.0006-0.01) was derived for transformation of 8:2 FTOH to PFOA. An uncertainty analysis was performed, and it was determined that the input parameters quantifying the intake of PFOA were mainly responsible for the uncertainty of the metabolism yield and the initial concentration of PFOA in serum was mainly contributing to the uncertainty of estimated serum half-lives.

  15. Alteration of the serum N-glycome of mice locally exposed to high doses of ionizing radiation.

    PubMed

    Chaze, Thibault; Slomianny, Marie-Christine; Milliat, Fabien; Tarlet, Georges; Lefebvre-Darroman, Tony; Gourmelon, Patrick; Bey, Eric; Benderitter, Marc; Michalski, Jean-Claude; Guipaud, Olivier

    2013-02-01

    Exposure of the skin to ionizing radiation leads to characteristic reactions that will often turn into a pathophysiological process called the cutaneous radiation syndrome. The study of this disorder is crucial to finding diagnostic and prognostic bioindicators of local radiation exposure or radiation effects. It is known that irradiation alters the serum proteome content and potentially post-translationally modifies serum proteins. In this study, we investigated whether localized irradiation of the skin alters the serum glycome. Two-dimensional differential in-gel electrophoresis of serum proteins from a man and from mice exposed to ionizing radiation showed that potential post-translational modification changes occurred following irradiation. Using a large-scale quantitative mass-spectrometry-based glycomic approach, we performed a global analysis of glycan structures of serum proteins from non-irradiated and locally irradiated mice exposed to high doses of γ-rays (20, 40, and 80 Gy). Non-supervised descriptive statistical analyses (principal component analysis) using quantitative glycan structure data allowed us to discriminate between uninjured/slightly injured animals and animals that developed severe lesions. Decisional statistics showed that several glycan families were down-regulated whereas others increased, and that particular structures were statistically significantly changed in the serum of locally irradiated mice. The observed increases in multiantennary N-glycans and in outer branch fucosylation and sialylation were associated with the up-regulation of genes involved in glycosylation in the liver, which is the main producer of serum proteins, and with an increase in the key proinflammatory serum cytokines IL-1β, IL-6, and TNFα, which can regulate the expression of glycosylation genes. Our results suggest for the first time a role of serum protein glycosylation in response to irradiation. These protein-associated glycan structure changes might

  16. Health impacts of exposure to second hand smoke (SHS) amongst a highly exposed workforce: survey of London casino workers

    PubMed Central

    Pilkington, Paul A; Gray, Selena; Gilmore, Anna B

    2007-01-01

    Background Casino workers are exposed to high levels of secondhand smoke (SHS) at work, yet remain at risk of being excluded from smoke-free legislation around the world. If the prime motivation for smoke-free legislation is the protection of workers, then a workforce experiencing ill-health associated with SHS exposure should not be excluded from legislation. This study aimed to determine the prevalence of respiratory and sensory irritation symptoms among a sample of casino workers, to identify any association between the reporting of symptoms and exposure to SHS at work, and to compare the prevalence of symptoms with that in other workers exposed to SHS. Methods A postal questionnaire survey of 1568 casino workers in London. Using multivariate analysis we identified predictors of respiratory and sensory irritation symptoms. Results 559 workers responded to the questionnaire (response of 36%). 91% of casino workers reported the presence of one or more sensory irritation symptoms in the previous four weeks, while the figure was 84% for respiratory symptoms. The presence of one or more sensory irritation symptoms was most strongly associated with reporting the highest exposure to SHS at work (OR 3.26; 1.72, 6.16). This was also true for reporting the presence of one or more respiratory irritation symptoms (OR 2.24; 1.34, 3.74). Prevalence of irritation symptoms in the casino workers was in general appreciably higher than that reported in studies of bar workers. Conclusion Our research supports the need for comprehensive smoke-free legislation around the world, covering all indoor workplaces including casinos. PMID:17888155

  17. High Seroprevalence for Typhus Group Rickettsiae, Southwestern Tanzania

    PubMed Central

    Dill, Tatjana; Dobler, Gerhard; Saathoff, Elmar; Clowes, Petra; Kroidl, Inge; Ntinginya, Elias; Machibya, Harun; Maboko, Leonard; Löscher, Thomas; Hoelscher, Michael

    2013-01-01

    Rickettsioses caused by typhus group rickettsiae have been reported in various African regions. We conducted a cross-sectional survey of 1,227 participants from 9 different sites in the Mbeya region, Tanzania; overall seroprevalence of typhus group rickettsiae was 9.3%. Risk factors identified in multivariable analysis included low vegetation density and highway proximity. PMID:23347529

  18. Dietary L-arginine supplement alleviates hepatic heat stress and improves feed conversion ratio of Pekin ducks exposed to high environmental temperature.

    PubMed

    Zhu, W; Jiang, W; Wu, L Y

    2014-12-01

    The current intensive indoor production system of commercial Pekin ducks never allows adequate water for swimming or wetting. Therefore, heat stress is a key factor affecting health and growth of ducks in the hot regions and season. Experiment 1 was conducted to study whether heat stress was deleterious to certain organs of ducks. Forty-one-day-old mixed-sex Pekin ducks were randomly allocated to four electrically heated battery brooders comprised of 10 ducks each. Ducks were suddenly exposed to 37 °C ambient temperature for 3 h and then slaughtered, in one brooder at 21 days and in another brooder at 49 days of age. The results showed that body weight and weight of immune organs, particularly liver markedly decreased in acute heat stress ducks compared with the control. Experiment 2 was carried out to investigate the influences of dietary L-arginine (Arg) supplement on weight and compositions of certain lymphoid organs, and growth performance in Pekin ducks, under daily cyclic hot temperature environment. A total of 151-day-old mixed-sex Pekin ducks were randomly divided into one negative control and two treatment groups, fed experimental diets supplemented with 0, 5, and 10 g L-Arginine (L-Arg)/kg to the basal diet respectively. Ducks were exposed to cyclic high temperature simulating natural summer season. The results showed that the addition of L-Arg improves feed conversion ratio (FCR) during a period of 7-week trial, as well as increases hepatic weight relative to body weight at 21 days, while decreases the hepatic water content at 49 days of age. This study indicated that the liver was more sensitive to acute heat stress, and the hepatic relative weight and chemical composition could be regulated by dietary L-Arg supplementation in Pekin ducks being reared at high ambient temperature. These beneficial effects of Arg on liver might be a cause of improved FCR.

  19. Average Exceptional Lie Group Hierarchy and High Energy Physics

    SciTech Connect

    El Naschie, M. S.

    2008-05-29

    Starting from an invariant total dimension for an exceptional Lie symmetry groups hierarchy, we drive all the essential characteristic and coupling constants of the fundamental interactions of physics. It is shown in a most simplistic fashion that all physical fields are various transfinite scaling transformation and topological deformation of each other. An extended standard model on the other hand turned out to be a compact sub group H of a version of E7 exceptional Lie group E7(-5) with dim H = 69. Thus particle physics, electromagnetism as well as gravity and the bulk are all representable via modular spaces akin to the famous compactified version of F. Klein's modular curve.

  20. Safety Guidelines for Laser Illumination on Exposed High Explosives and Metals in Contact with High Explosives with Calculational Results

    SciTech Connect

    Benterou, J; Roeske, F; Wilkins, P; Carpenter, K H

    2002-04-17

    Experimental tests have been undertaken to determine safe levels of laser exposure on bare high explosive (HE) samples and on common metals used in intimate contact with HE. Laser light is often focused on bare HE and upon metals in contact with HE during alignment procedures and experimental metrology experiments. This paper looks at effects caused by focusing laser beams at high energy densities directly onto the surface of various bare HE samples. Laser energy densities (fluence) exceeding 19 kilowatts/cm{sup 2} using a 5-milliwatt, 670 nm, cw laser diode were generated by focusing the laser down to a spot size diameter of 4 microns. Upon careful inspection, no laser damage was observed in any of the HE samples illuminated at this fluence level. Direct laser exposure of metals directly contacting HE surfaces was also tested. Laser energy densities (fluence) varying from 188 Watts/cm{sup 2} to 12.7 KW/cm{sup 2} were generated using an 11-Watt, 532 nm frequency-doubled Nd:YAG cw laser with focal spot size diameters as small as 100 microns. These measurements look at the temperature rise of the surface of the metal in contact with HE when laser energy is incident on the opposite side of the metal. The temperature rise was experimentally measured as a function of incident laser power, spot size, metal composition and metal thickness. Numerical simulations were also performed to solve the two-dimensional heat flow problem for this experimental geometry. In order to simplify the numerical simulation to allow representation of a large number of physical cases, the equations used in the simulation are expressed in terms of dimensionless variables. The normalized numerical solutions are then compared to the various experimental configurations utilized. Calculations and experiment agree well over the range measured. Safety guidelines for alignment laser illumination upon bare HE are outlined.

  1. Investigation of the oxidation behavior of dispersion stabilized alloys when exposed to a dynamic high temperature environment

    NASA Technical Reports Server (NTRS)

    Tenney, D. R.

    1974-01-01

    The oxidation behavior of TD-NiCr and TD-NiCrAlY alloys have been studied at 2000 and 2200 F in static and high speed flowing air environments. The TD-NiCrAlY alloys preoxidized to produce an Al2O3 scale on the surface showed good oxidation resistance in both types of environments. The TD-NiCr alloy which had a Cr2O3 oxide scale after preoxidation was found to oxidize more than an order of magnitude faster under the dynamic test conditions than at comparable static test conditions. Although Cr2O3 normally provides good oxidation protection, it was rapidly lost due to formation of volatile CrO3 when exposed to the high speed air stream. The preferred oxide arrangement for the dynamic test consisted of an external layer of NiO with a porous mushroom type morphology, an intermediate duplex layer of NiO and Cr2O3, and a continuous inner layer of Cr2O3 in contact with the alloy substrate. An oxidation model has been developed to explain the observed microstructure and overall oxidation behavior of all alloys.

  2. Electrocardiographic abnormalities among arsenic-exposed persons through groundwater in Bangladesh.

    PubMed

    Ahmad, S Akhtar; Khatun, Fatema; Sayed, M H Salim Ullah; Khan, Manzurul Haque; Aziz, Rashed; Hossain, Mohammed Zakir; Faruquee, M H

    2006-06-01

    This study was carried out among arsenic-exposed and non-exposed people of Bangladesh to assess and compare their cardiac status based on electrocardiographic (ECG) findings. For the purpose of the study, participants were included in three groups: arsenic-exposed persons with arsenicosis (arsenicosis group), arsenic-exposed persons without arsenicosis (non-arsenicosis group), and persons not exposed to arsenic (non-exposed group). Each group included 50 respondents. In this study, no significant difference in heart rate, rhythm, axis, and pulse rate interval was detected among the arsenicosis, non-arsenicosis and non-exposed groups. A significant difference in corrected QT interval between the arsenicosis and the non-exposed group (p<0.05) was observed. On the contrary, no statistically significant difference in corrected QT interval between the non-arsenicosis and the non-exposed group was found. Abnormal QRS complex was found among 14%, 8%, and 2% of the arsenicosis, non-arsenicosis, and non-exposed groups respectively. ECG findings, indicative of left ventricular hypertrophy, ischaemic heart disease, and right bundle branch block, were high among the arsenicosis group. Overall, abnormal ECG findings were high (58%) among the respondents of the arsenicosis group and were highly significant (p<0.001). The findings revealed that there was a significant association between ECG abnormalities and arsenic exposure.

  3. Effect of Vitamin E Supplementation on Intestinal Barrier Function in Rats Exposed to High Altitude Hypoxia Environment

    PubMed Central

    Sun, Rui; Qiao, Xiangjin; Xu, Cuicui; Shang, Xiaoya; Niu, Weining; Chao, Yu

    2014-01-01

    The study was conducted to investigate the role of vitamin E in the high altitude hypoxia-induced damage to the intestinal barrier in rats. Sprague-Dawley rats were divided into control (Control), high altitude hypoxia (HH), and high altitude hypoxia+vitamin E (250 mg/kg BW*d) (HV) groups. After the third day, the HH and HV groups were placed in a hypobaric chamber at a stimulated elevation of 7000 m for 5 days. The rats in the HV group were given vitamin E by gavage daily for 8 days. The other rats were given equal volume saline. The results showed that high altitude hypoxia caused the enlargement of heart, liver, lung and kidney, and intestinal villi damage. Supplementation with vitamin E significantly alleviated hypoxia-caused damage to the main organs including intestine, increased the serum superoxide dismutase (SOD) (p< 0.05), diamino oxidase (DAO) (p< 0.01) levels, and decreased the serum levels of interleukin-2 (IL-2) (p< 0.01), interleukin-4 (IL-4) (p<0.001), interferon-gamma (IFN-γ) (p<0.01) and malondialdehyde (MDA) (p<0.001), and decreased the serum erythropoietin (EPO) activity (p<0.05). Administration of vitamin E significantly increased the S-IgA (p<0.001) in ileum and significantly improved the expression levels of occludin and IκBα, and decreased the expression levels of hypoxia-inducible factor 1 alpha and 2 alpha (HIF-1α and HIF-2α), Toll-like receptors (TLR4), P-IκBα and nuclear factor-κB p65(NF-κB P65) in ileum compared to the HH group. This study suggested that vitamin E protectis from intestinal injury caused by high altitude hypoxia environment. These effects may be related to the HIF and TLR4/NF-κB signaling pathway. PMID:25177163

  4. Real-time measurements of temperature, pressure and moisture profiles in High-Performance Concrete exposed to high temperatures during neutron radiography imaging

    SciTech Connect

    Toropovs, N.; Lo Monte, F.; Wyrzykowski, M.; Weber, B.; Sahmenko, G.; Vontobel, P.; Felicetti, R.; Lura, P.

    2015-02-15

    High-Performance Concrete (HPC) is particularly prone to explosive spalling when exposed to high temperature. Although the exact causes that lead to spalling are still being debated, moisture transport during heating plays an important role in all proposed mechanisms. In this study, slabs made of high-performance, low water-to-binder ratio mortars with addition of superabsorbent polymers (SAP) and polypropylene fibers (PP) were heated from one side on a temperature-controlled plate up to 550 °C. A combination of measurements was performed simultaneously on the same sample: moisture profiles via neutron radiography, temperature profiles with embedded thermocouples and pore pressure evolution with embedded pressure sensors. Spalling occurred in the sample with SAP, where sharp profiles of moisture and temperature were observed. No spalling occurred when PP-fibers were introduced in addition to SAP. The experimental procedure described here is essential for developing and verifying numerical models and studying measures against fire spalling risk in HPC.

  5. Aryl hydrocarbon receptor expression is associated with a family history of upper gastrointestinal tract cancer in a high-risk population exposed to aromatic hydrocarbons

    SciTech Connect

    Roth, M.J.; Wei, W.Q.; Baer, J.; Abnet, C.C.; Wang, G.Q.; Sternberg, L.R.; Warner, A.C.; Johnson, L.L.; Lu, N.; Giffen, C.A.; Dawsey, S.M.; Qiao, Y.L.; Cherry, J.

    2009-09-15

    Polycyclic aromatic hydrocarbon (PAH) exposure is a risk factor for esophageal squamous cell carcinoma, and PAHs are ligands of the aryl hydrocarbon receptor (AhR). This study measured the expression of AhR and related genes in frozen esophageal cell samples from patients exposed to different levels of indoor air pollution, who did or did not have high-grade squamous dysplasia and who did or did not have a family history of upper gastrointestinal tract (UGI) cancer. 147 samples were evaluated, including 23 (16%) from patients with high-grade dysplasia and 48 (33%) from patients without dysplasia who heated their homes with coal, without a chimney (a 'high' indoor air pollution group), and 27 (18%) from patients with high-grade dysplasia and 49 (33%) from patients without dysplasia who did not heat their homes at all (a 'low' indoor air pollution group). Sixty-four (44%) had a family history of UGI cancer. RNA was extracted and quantitative PCR analysis was done. AhR gene expression was detectable in 85 (58%) of the samples and was >9-fold higher in those with a family history of UGI cancer (median expression (interquartile range), -1,964 (-18,000, -610) versus -18,000 (-18,000, -1036); P = 0.02, Wilcoxon rank-sum test). Heating status, dysplasia category, age, gender, and smoking were not associated with AhR expression (linear regression; all P values {ge} 0.1). AhR expression was higher in patients with a family history of UGI cancer. Such individuals may be more susceptible to the deleterious effects of PAH exposure, including PAH-induced cancer.

  6. High Performance Liquid Chromatography Coupled with Pre-column Derivatization for Determination of Oxidized Glutathione Level in Rats Exposed to Paraquat.

    PubMed

    Hami, Zahra; Amini, Mohsen; Kiani, Amir; Ghazi-Khansari, Mahmoud

    2013-01-01

    Glutathione (GSH) is one of the most important antioxidants that plays an essential role in detoxification of reactive oxygen species (ROS) which oxidizes to glutathione disulfide (GSSG). Paraquat (PQ), awidely used herbicide, causes pulmonary injury with the productionof ROS. Excessive ROS accumulation as a consequence of PQ exposure are frequently targeted by GSH thereby oxidative stress leads to depletion of cellular GSH by transforming of GSH to glutathione disulfide (GSSG). A precise method of measuring of GSSG concentration in plasma as indicator of oxidative stress is needed. Some analytical techniques such as high-performance liquid chromatography (HPLC), gas chromatography and capillary electrophoresis have been used for determination of GSSG concentration. In the present study, a new HPLC method with fluorescence detection based on derivatization of the amine group of glutathione with 9-fluorenylmethyl chloroformate (FMOC-Cl) was developed. Male Wistar albino rats exposed to different doses of PQ (20-60 mg/kg) and control group were used and after protein precipitation, their plasma was subjected to derivatization with FMOC in the presence of borate buffer. The derivatized samples were injected to HPLC system with C18 column, mobile phase consisting of methanol and phosphate buffer, λem= 315 nm, λex= 260 nm. Among all experimental groups, the rats which received 60 mg/kg PQ, showed a significant increase in the amount of oxidized glutathione (GSSG) compared to the control group. In this study, the applied derivatization and HPLC method made it possible to measure small amounts of glutathione in plasma using a precise and sensitive technique.

  7. Uranium Series Diagenesis in Corals Exposed to Fresh Water: Toward Better Prospecting for Closed System Samples for High Accuracy Dating

    NASA Astrophysics Data System (ADS)

    Mey, J.; Fairbanks, R.; Mortlock, R.; Bradtmiller, L.

    2005-12-01

    A better understanding of U-series diagenesis in corals exposed to the vadose and phreatic freshwater environments is required to help prospect for closed-system samples needed for high-accuracy dates. Disequilibrium U-series are common in corals exposed to fresh water and a priori screening is generally insufficient to reject samples prior to dating. As a result, a vast number of U-series dates reported in the literature are open system and numerous authors have resorted to various correction models (Bender et al., 1979; Gallup et al., 1994; Thompson et al., 2003; Villemant and Feuillet, 2003; and Scholz et al., 2004). The majority of studies assumes or models continuous or episodic addition of 234U and/or 230Th over time and relies on the low solubility of 230Th and/or 234Th. Several recent studies emphasize progressive production of 234U via α-recoil (Thompson et al., 2003; Villemant and Feuillet, 2003), however the application of these models may lead to over-parameterization and are mainly idiosyncratic to host sample locations (Scholz et al., 2004). Already, some studies make model corrections to open system ages and draw critical conclusions about sea level change (e.g. Scholz et al., 2004; Thompson and Goldstein, 2005). Characteristic of all of these studies is a general correlation between the 234U/238U activity ratio and the 230Th/238U activity ratio between intra-reef samples. On Barbados, the largest activity ratio offsets appear in the youngest samples exposed to fresh water; just the opposite finding of most diagenesis models. Our measurements are consistent with the observations of Scholz et al. (2004) from the Red Sea. The greatest addition of 234U, 230Th, and 231Pa to the Barbados samples occurred during the first exposure to fresh water, in this case Marine Isotope State 3 (MIS3), when 234U, 230Th, and 231Pa are added to samples in similar proportions, but varying amounts. The bulk of reef sands and rubble is aragonite, which releases U

  8. The Highly Perturbed X-ray Bright Group NGC 5044

    NASA Astrophysics Data System (ADS)

    David, Laurence

    2014-09-01

    The NGC 5044 group is the X-ray brightest group in the sky and hosts many small X-ray cavities that were inflated by weak AGN outbursts. The cumulative effect of many weak AGN outbursts may be the dominant reheating mechanism in cooling flows. While AGN feedback probably prevents the bulk of gas from cooling in NGC 5044, the presence of molecular structures, Halpha filaments, [CII] emission and star formation indicates that at least some gas is able to condense out of the hot phase. The near by 5044 group is the best target for detecting small X-ray cavities with Chandra and investigating the cumulative effect of repeated weak AGN outbursts. The wealth of multi-frequency data also makes NGC 5044 an ideal target for studying gas over a broad range of temperatures in a cooling flow.

  9. Apoptosis and biochemical biomarkers of stress in spiders from industrially polluted areas exposed to high temperature and dimethoate.

    PubMed

    Wilczek, Grazyna

    2005-06-01

    The aim of this study was to evaluate the relations between apoptosis and the activity of antioxidant enzymes (superoxide dismutase; catalase) and quantitative changes in stress protein positive cells (Hsp70; metallothionein) in midgut glands of funnel web spiders Agelena labyrinthica (Agelenidae) and wolf spiders Pardosa lugubris (Lycosidae) exposed to high temperature and pesticide under laboratory conditions. The spiders were collected from two meadow ecosystems differently polluted with metals (Olkusz and Pilica, southern Poland). Under stress conditions, P. lugubris had fewer apoptotic cells in the midgut glands than A. labyrinthica. In P. lugubris from both sites, the observed increase in the percentage of metallothionein and Hsp70-positive cells, simultaneous with intensification of superoxide dismutase and catalase activity, suggests an anti-apoptotic function of those proteins in representatives of wandering spiders. In the midgut glands of A. labyrinthica, heat shock and dimethoate increased the number of Annexin V-positive cells as well as the amounts of mitochondria with low transmembrane potential (DeltaPsi(m)) versus the control. The changes in the percentage of MT- and Hsp70-positive cells in funnel web spiders were less than in wolf spiders. The absence of change in SOD and CAT activity in A. labyrinthica shows that the participation of those enzymes in antioxidant reactions is minimal in this species.

  10. Phase and Structural States Formed in Titanium Nickelide Subsurface Layers Exposed to High-Current Pulsed Electron Beams

    NASA Astrophysics Data System (ADS)

    Neyman, A. A.; Meisner, L. L.; Lotkov, A. I.; Semin, V. O.

    2015-06-01

    The behavior of the non-equilibrium states formed in the subsurface layers of a titanium nickelide-based alloy exposed to electron beams operated in the pulsed surface layer melting mode is investigated experimentally. Using methods of an x-ray diffraction analysis, and optical, scanning, and transmission electron microscopies, an 8-10 μm thick surface layer is shown to exhibit В2 phase-based structure undergoing inhomogeneous lattice microstrain. The core layer located at a depth of 10-20 μm below the irradiated surface contains a small amount (up to 5 vol.%) of a phase with В19' martensite structure along with a slightly distorted lattice and unmelted Ti2Ni phase particles. Electron beam treatment brings about changes in the chemical composition of the surface-modified layer which becomes enriched in titanium owing to the dissolution of the Ti2Ni phase particles therein. Transmission electron microscopy has not revealed martensite phases in the modified layer. The electron beam exposure of the titanium nickelide surface is assumed to give rise to nonequilibrium highly distorted bcc structure.

  11. The Keenan Project: Comprehensive Group Guidance in High School.

    ERIC Educational Resources Information Center

    Cooper-Haber, Karen; Bowman, R. P.

    1985-01-01

    Describes the Keenan Project in Columbia, South Carolina, which provides ongoing group guidance to students on various topics, including communication skills, family concerns, and study skills. Its success is attributed to careful attention to building support, using available resources, including other staff members, and following systematic…

  12. High School Biology: A Group Approach to Concept Mapping.

    ERIC Educational Resources Information Center

    Brown, David S.

    2003-01-01

    Explains concept mapping as an instructional method in cooperative learning environments, and describes a study investigating the effectiveness of concept mapping on student learning during a photosynthesis and cellular respiration unit. Reports on the positive effects of concept mapping in the experimental group. (Contains 16 references.) (YDS)

  13. Ultrastructural findings in the brain of fruit flies (Drosophila melanogaster) and mice exposed to high-energy particle radiation

    SciTech Connect

    D'Amelio, F.; Kraft, L.M.; D'Antoni-D'Amelio, E.; Benton, E.V.; Miquel, J.

    1984-01-01

    Effects of high energy, heavy particle (HZE) radiation were studied in the brain of the fruit fly (Drosophila melanogaster) exposed to argon (40Ar) or krypton (84Kr) ions. In the flies exposed to argon the fluence ranged from 6 X 10(4) to 8 X 10(7) particles/cm2. The insects were killed 35 days after exposure. Extensive tissue fragmentation was observed at the higher fluence employed. At fluences ranging from 5 X 10(6) (one hit/two cell bodies) to 9 X 10(4) (one hit/90 cell bodies) particles/cm2, swelling of the neuronal cytoplasm and focally fragmented membranes was observed. Marked increase of glial lamellae around nerve cell processes was seen at fluences ranging from one hit/six to one hit/135 cell bodies. In the flies irradiated with krypton, the fluences employed were 5.8 X 10(3) and 2.2 X 10(6) particles/cm2. Acute and late effects were evaluated. In the flies killed 36 hours after exposure (acute effects) to either fluence, glycogen particles were found in the neuroglial compartment. The granules were no longer present in flies killed 35 days later (late effects). From these studies it appears that the Drosophila brain is a useful model to investigate radiation damage to mature neurons, neuroglia, and therefore, to the glio-neuronal metabolic unit. In a separate study, the synaptic profiles of the neuropil in layers II-III of the frontal cerebral cortex of anesthesized adult LAFl mice were quantitatively appraised after exposure to argon (40Ar) particles. The absorbed dose ranged from 0.05 to 5 gray (Gy) plateau. It was determined that the sodium pentobarbital anesthesia per se results in a significant decrease in synaptic profile length one day after anesthetization, with return to normal values after 2-28 days. Irradiation with 0.05-5 Gy argon particles significantly inhibited the synaptic shortening effect of anesthesia at one day after exposure.

  14. Partitioning of absorbed light energy differed between the sun-exposed side and the shaded side of apple fruits under high light conditions.

    PubMed

    Chen, Changsheng; Zhang, Di; Li, Pengmin; Ma, Fengwang

    2012-11-01

    Fractions of absorbed light energy consumed via photochemistry and different thermal dissipation processes was quantified and compared between the sun-exposed peel and the shaded peel of apple fruits at different developmental stages. During fruit development, the fraction of absorbed light consumed via photochemistry was no more than 7% in the sun-exposed peel and no more than 5% in the shaded peel under high light conditions. Under high light, the fraction of absorbed light energy consumed via light dependent thermal dissipation was higher whereas that via constitutive thermal dissipation was lower in the sun-exposed peel. The light dependent thermal dissipation in the sun-exposed peel mainly depended on the xanthophyll cycle, and the xanthophyll cycle pool size was significantly larger in the sun-exposed peel than in the shaded peel. The light dependent thermal dissipation in the shaded peel was dependent on both the xanthophyll cycle and the presence of inactivated reaction centers. Under high light conditions, the densities of both Q(A)-reducing reaction centers and Q(B)-reducing reaction centers decreased faster in the shaded peel than in the sun-exposed peel. The thermal dissipation related to photoinhibition increased and then kept unchanged in the sun-exposed peel but decreased in the shaded peel during fruit development. We conclude that under high light intensities, fruit peel looses the excess energy in order of predominance: first by the xanthophyll cycle, then the thermal dissipation related to photoinhibition, next through inactivated reaction centers, and finally by constitutive thermal dissipation.

  15. Phlebotomy Treatment for Elimination of Perfluoroalkyl Acids in a Highly Exposed Family: A Retrospective Case-Series

    PubMed Central

    Genuis, Stephen J.; Liu, Yanna; Genuis, Quentin I. T.; Martin, Jonathan W.

    2014-01-01

    diminish the body burden of PFAAs in highly exposed people. PMID:25504057

  16. Noise-induced hearing loss: A possible marker for high blood pressure in older noise-exposed populations

    SciTech Connect

    Talbott, E.O.; Findlay, R.C.; Kuller, L.H.; Lenkner, L.A.; Matthews, K.A.; Day, R.D.; Ishii, E.K. )

    1990-08-01

    The present study assessed the relationships among occupational noise exposure, noise-induced hearing loss, and high blood pressure. The study population consisted of 245 retired metal assembly workers from Pittsburgh aged 56 to 68 with chronic noise exposure of 30 or more years at greater than or equal to 89 dBA. Results of the audiometric testing indicated 52% of the younger workers (ages 56 to 63) have severe noise-induced hearing loss (greater than or equal to 65 dBA loss at 3, 4, or 6 kHz) and 67% of older workers (ages 64 to 68). Body mass index and alcohol intake were significantly related to systolic and diastolic blood pressure. Among older men, there was a marginally significant increased prevalence of high blood pressure (greater than or equal to 90 mm diastolic or taking blood pressure medicine) among those with severe noise-induced hearing loss (P = .05). Moreover, another measure of hearing loss at high frequencies, speech discrimination score in noise (measured in the better ear), referred to as the W-22 MAX score, was also found to be related to the prevalence of high blood pressure in the older (64 to 68) age group (P less than .05). Multiple regression analysis revealed W-22 MAX and severe noise-induced hearing loss were independent predictors of hypertension in the older, but not in the younger group of retired workers.

  17. Animal Welfare Groups Press for Limits on High School Research.

    ERIC Educational Resources Information Center

    BioScience, 1979

    1979-01-01

    Discussions from the conference on "The Use of Animals in High School Biology Classes" are highlighted in this article. The list of science fair rules, which resulted from the conference, is included. (SA)

  18. Mechanisms of modulation of cytokine release by human cord blood monocytes exposed to high concentrations of caffeine

    PubMed Central

    Chavez-Valdez, Raul; Ahlawat, Rajni; Wills-Karp, Marsha; Gauda, Estelle B.

    2016-01-01

    Background Serum caffeine concentrations >20µg/mL (100 µM) in infants treated for apnea of prematurity increases TNF-α and decreases IL-10, change that perhaps is linked to co-morbidities. We hypothesize that this pro-inflammatory cytokine profile may be linked to differential binding of caffeine to adenosine receptor subtypes (AR), inhibition of phosphodiesterases (PDEs), and modulation of toll-like receptors (TLR). Methods LPS-activated cord blood monocytes (CBM) from 19 infants were exposed to caffeine (0 to 200 µM) with or without previous exposure to A1R, A3R, or PDE IV antagonists to determine changes in dose-response curves. Cytokines levels (ELISA), intracellular cAMP accumulation (EIA) and TLR gene expression (real time qRT PCR) were measured. Results Caffeine at ≤100µM decreased TNF-α levels (~25%, p=0.01) and cAMP. All caffeine concentrations decreased IL-10 levels (17 to 35%, p<0.01). A1R, A3R and PDE blockades decreased TNF-α (31%, 21%, and 88%, p≤0.01), but not IL-10. Caffeine further decreased TNF-α following A3R and PDE blockades. Caffeine concentrations directly correlated to TLR4 gene expression (r=0.84; p<0.001). Conclusion Neither A3R, nor PDE blockades are involved in caffeine’s modulation of cytokine release by CBM at any concentration. Besides A1R blockade, caffeine’s up-regulation of TLR4 may promote inflammation at high concentrations. PMID:26982450

  19. High-resolution δ13CO2 soil efflux monitoring in tree girdling experiment exposes large temporal variability

    NASA Astrophysics Data System (ADS)

    Egan, J. E.; Risk, D. A.; Nickerson, N. R.

    2011-12-01

    Carbon stable isotopes (δ13C) help us link above- and below-ground ecosystem processes, telling us about the temporal speed at which carbon cycles through plants to the soil and the amount of autotrophic respiration contributing to total soil respiration. In the past few years, we have seen rapid advances in the way we measure δ13CO2, using Tunable Diode Lasers (TDL) or Cavity Ring Down Spectroscopy (CRDS), which has helped make us aware of the high isotopic variability in natural soils. There is also growing recognition that most sampling strategies induce gas transport fractionations, which can be of high magnitude. Previous high profile studies using δ13CO2 are increasingly being called into question for these reasons, as variability or transport fractionations may have overprinted the biologic variability of interest. Our aim in this study was to conduct a girdling experiment similar to other widely cited girdling experiments, where we were interested in identifying isotopic signatures and magnitudes of respiration associated with autotrophic and heterotrophic activity, the temporal link between photosynthesis and respiration, and spatial variation within treatment plots. Our study is different from previous studies in that it relies on automated continuous CRDS measurements from several locations, using a sampling methodology that we developed specifically to address previous fractionation issues. The new methodology, called Isotopic-Forced Diffusion (Iso-FD), measures δ13CO2 efflux. It was tested in the lab and using models, and then implemented in the field for the tree girdling experiment in two 400-m2 pine plots in Antigonish County, NS, Canada. In addition to Iso-FD continuous data, spatial δ13CO2 data from gas chambers, and meteorological data were also collected in growing seasons of both 2010 and 2011. Variation was seen in bulk flux rates between the plots, and girdling both resulted in increased CO2 fluxes and decreased temporal variability in

  20. Chromosome Aberrations in Human Epithelial Cells Exposed Los Alamos High-Energy Secondary Neutrons: M-BAND Analysis

    NASA Technical Reports Server (NTRS)

    Hada, M.; Saganti, P. B.; Gersey, B.; Wilkins, R.; Cucinotta, F. A.; Wu, H.

    2007-01-01

    High-energy secondary neutrons, produced by the interaction of galactic cosmic rays (GCR) with the atmosphere, spacecraft structure and planetary surfaces, contribute a significant fraction to the dose equivalent radiation measurement in crew members and passengers of commercial aviation travel as well as astronauts in space missions. The Los Alamos Nuclear Science Center (LANSCE) neutron facility's 30L beam line (4FP30L-A/ICE House) is known to generate neutrons that simulate the secondary neutron spectrum of the Earth's atmosphere at high altitude. The neutron spectrum is also similar to that measured onboard spacecrafts like the MIR and the International Space Station (ISS). To evaluate the biological damage, we exposed human epithelial cells in vitro to the LANSCE neutron beams with an entrance dose rate of 2.5 cGy/hr, and studied the induction of chromosome aberrations that were identified with multicolor-banding in situ hybridization (mBAND) technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of inter-chromosomal aberrations (translocation to unpainted chromosomes) and intra-chromosomal aberrations (inversions and deletions within a single painted chromosome). Compared to our previous results with gamma-rays and 600 MeV/nucleon Fe ions of high dose rate at NSRL (NASA Space Radiation Laboratory at Brookhaven National Laboratory), the neutron data from the LANSCE experiments showed significantly higher frequency of chromosome aberrations. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. Most of the inversions in gamma-ray irradiated samples were accompanied by other types of intrachromosomal aberrations but few inversions were accompanied by interchromosomal aberrations. In contrast, neutrons and Fe ions induced a significant fraction of inversions that involved complex rearrangements of both

  1. High pressure phase transition in group III nitrides compounds

    NASA Astrophysics Data System (ADS)

    Soni, Shubhangi; Verma, S.; Kaurav, Netram; Choudhary, K. K.

    2016-05-01

    Using an effective interionic interaction potential (EIOP), the pressure induced structural phase transformation from ZnS-type (B3) to NaCl-type (B1) structure in group III Post-Transition Metal Nitrides [TMN; TM=Ga and Tl] were investigated. The long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach with modified ionic charge are properly incorporated in the EIOP. The vdW coefficients are computed following the Slater-Kirkwood variational method, as both the ions are polarizable. The estimated value of the phase transition pressure (Pt) and the magnitude of the discontinuity in volume at the transition pressure are consistent as compared to the reported data.

  2. Low-temperature synthesis of high-ordered anatase TiO2 nanotube array films coated with exposed {001} nanofacets

    PubMed Central

    Ding, Jie; Huang, Zhennan; Zhu, Jihao; Kou, Shengzhong; Zhang, Xiaobin; Yang, Hangsheng

    2015-01-01

    High-ordered anatase TiO2 nanotube array films coated with exposed high-reactive {001} nanofacets were fabricated by a modified hydrothermal method using amorphous anodic TiO2 nanotube arrays (ATONAs) as starting materials. It was found that the reaction between gas phase HF and solid ATONAs played a key role in the transformation process from amorphous to anatase TiO2, and the TiO2 tubular structure kept unchanged during the surface modification with an exposed {001} facets up to 76.5%, which could be attributed to the low reaction temperature of 130 °C. Our study provided a novel route for the facile preparation of {001} facets exposed anatase TiO2. PMID:26634815

  3. Distribution of influenza vaccine to high-risk groups.

    PubMed

    Ompad, Danielle C; Galea, Sandro; Vlahov, David

    2006-01-01

    Vaccine distribution programs have historically targeted individuals at high risk of complications due to influenza. Despite recommendations from the Advisory Committee on Immunization Practices, vaccination coverage among high-risk populations has been generally low. This review systematically summarizes the recent literature evaluating programs in different settings, from within medical settings to venue-based and community-based approaches, in an effort to identify successful program components. The published literature was identified by using the MEDLINE database from 1990 to 2006 covering studies that reported on interventions or programs aimed at vaccinating high-risk populations. The authors reviewed 56 studies. In the United States, the Healthy People 2010 goals included 90% vaccination coverage for adults aged > or = 65 years and 60% for high-risk adults aged 18-64 years. Only a handful of the studies reviewed managed to meet those goals. Interventions that increased vaccination coverage to Healthy People 2010 goals included advertising, provider and patient mailings, registry-based telephone calls, patient and staff education, standing orders coupled with standardized forms, targeting of syringe exchange customers, and visiting nurses. Few studies evaluated the impact of vaccination programs by race/ethnicity and socioeconomic status. Few studies targeted individuals outside of the health-care and social services sectors. Given the growing disparities in health and health-care access, understanding the way in which interventions can remedy disparities is crucial.

  4. Nontargeted stressful effects in normal human fibroblast cultures exposed to low fluences of high charge, high energy (HZE) particles: kinetics of biologic responses and significance of secondary radiations.

    PubMed

    Gonon, Géraldine; Groetz, Jean-Emmanuel; de Toledo, Sonia M; Howell, Roger W; Fromm, Michel; Azzam, Edouard I

    2013-04-01

    The induction of nontargeted stressful effects in cell populations exposed to low fluences of high charge (Z) and high energy (E) particles is relevant to estimates of the health risks of space radiation. We investigated the up-regulation of stress markers in confluent normal human fibroblast cultures exposed to 1,000 MeV/u iron ions [linear energy transfer (LET) ∼151 keV/μm] or 600 MeV/u silicon ions (LET ∼50 keV/μm) at mean absorbed doses as low as 0.2 cGy, wherein 1-3% of the cells were targeted through the nucleus by a primary particle. Within 24 h postirradiation, significant increases in the levels of phospho-TP53 (serine 15), p21(Waf1) (CDKN1A), HDM2, phospho-ERK1/2, protein carbonylation and lipid peroxidation were detected, which suggested participation in the stress response of cells not targeted by primary particles. This was supported by in situ studies that indicated greater increases in 53BP1 foci formation, a marker of DNA damage. than expected from the number of primary particle traversals. The effect was expressed as early as 15 min after exposure, peaked at 1 h and decreased by 24 h. A similar tendency occurred after exposure of the cell cultures to 0.2 cGy of 3.7 MeV α particles (LET ∼109 keV/μm) that targets ∼1.6% of nuclei, but not after 0.2 cGy from 290 MeV/u carbon ions (LET ∼13 keV/μm) by which, on average, ∼13% of the nuclei were hit, which highlights the importance of radiation quality in the induced effect. Simulations with the FLUKA multi-particle transport code revealed that fragmentation products, other than electrons, in cell cultures exposed to HZE particles comprise <1% of the absorbed dose. Further, the radial spread of dose due to secondary heavy ion fragments is confined to approximately 10-20 μm. Thus, the latter are unlikely to significantly contribute to stressful effects in cells not targeted by primary HZE particles.

  5. Nontargeted stressful effects in normal human fibroblast cultures exposed to low fluences of high charge, high energy (HZE) particles: kinetics of biologic responses and significance of secondary radiations.

    PubMed

    Gonon, Géraldine; Groetz, Jean-Emmanuel; de Toledo, Sonia M; Howell, Roger W; Fromm, Michel; Azzam, Edouard I

    2013-04-01

    The induction of nontargeted stressful effects in cell populations exposed to low fluences of high charge (Z) and high energy (E) particles is relevant to estimates of the health risks of space radiation. We investigated the up-regulation of stress markers in confluent normal human fibroblast cultures exposed to 1,000 MeV/u iron ions [linear energy transfer (LET) ∼151 keV/μm] or 600 MeV/u silicon ions (LET ∼50 keV/μm) at mean absorbed doses as low as 0.2 cGy, wherein 1-3% of the cells were targeted through the nucleus by a primary particle. Within 24 h postirradiation, significant increases in the levels of phospho-TP53 (serine 15), p21(Waf1) (CDKN1A), HDM2, phospho-ERK1/2, protein carbonylation and lipid peroxidation were detected, which suggested participation in the stress response of cells not targeted by primary particles. This was supported by in situ studies that indicated greater increases in 53BP1 foci formation, a marker of DNA damage. than expected from the number of primary particle traversals. The effect was expressed as early as 15 min after exposure, peaked at 1 h and decreased by 24 h. A similar tendency occurred after exposure of the cell cultures to 0.2 cGy of 3.7 MeV α particles (LET ∼109 keV/μm) that targets ∼1.6% of nuclei, but not after 0.2 cGy from 290 MeV/u carbon ions (LET ∼13 keV/μm) by which, on average, ∼13% of the nuclei were hit, which highlights the importance of radiation quality in the induced effect. Simulations with the FLUKA multi-particle transport code revealed that fragmentation products, other than electrons, in cell cultures exposed to HZE particles comprise <1% of the absorbed dose. Further, the radial spread of dose due to secondary heavy ion fragments is confined to approximately 10-20 μm. Thus, the latter are unlikely to significantly contribute to stressful effects in cells not targeted by primary HZE particles. PMID:23465079

  6. Nontargeted Stressful Effects in Normal Human Fibroblast Cultures Exposed to Low Fluences of High Charge, High Energy (HZE) Particles: Kinetics of Biologic Responses and Significance of Secondary Radiations

    PubMed Central

    Gonon, Géraldine; Groetz, Jean-Emmanuel; de Toledo, Sonia M.; Howell, Roger W.; Fromm, Michel; Azzam, Edouard I.

    2014-01-01

    The induction of nontargeted stressful effects in cell populations exposed to low fluences of high charge (Z) and high energy (E) particles is relevant to estimates of the health risks of space radiation. We investigated the up-regulation of stress markers in confluent normal human fibroblast cultures exposed to 1,000 MeV/u iron ions [linear energy transfer (LET) ~151 keV/μm] or 600 MeV/u silicon ions (LET ~50 keV/μm) at mean absorbed doses as low as 0.2 cGy, wherein 1–3% of the cells were targeted through the nucleus by a primary particle. Within 24 h postirradiation, significant increases in the levels of phospho-TP53 (serine 15), p21Waf1 (CDKN1A), HDM2, phospho-ERK1/2, protein carbonylation and lipid peroxidation were detected, which suggested participation in the stress response of cells not targeted by primary particles. This was supported by in situ studies that indicated greater increases in 53BP1 foci formation, a marker of DNA damage. than expected from the number of primary particle traversals. The effect was expressed as early as 15 min after exposure, peaked at 1 h and decreased by 24 h. A similar tendency occurred after exposure of the cell cultures to 0.2 cGy of 3.7 MeV α particles (LET ~109 keV/μm) that targets ~1.6% of nuclei, but not after 0.2 cGy from 290 MeV/u carbon ions (LET ~13 keV/μm) by which, on average, ~13% of the nuclei were hit, which highlights the importance of radiation quality in the induced effect. Simulations with the FLUKA multi-particle transport code revealed that fragmentation products, other than electrons, in cell cultures exposed to HZE particles comprise <1% of the absorbed dose. Further, the radial spread of dose due to secondary heavy ion fragments is confined to approximately 10–20 μm. Thus, the latter are unlikely to significantly contribute to stressful effects in cells not targeted by primary HZE particles. PMID:23465079

  7. Effect of intermittent hypoxia on the reproduction of rats exposed to high altitude in the Chilean Altiplano.

    PubMed

    Cikutovic, Marcos; Fuentes, Nelson; Bustos-Obregón, Eduardo

    2009-01-01

    Environmental parameters such as the large day-night temperature differences, high light radiation, and low humidity may have a synergistic effect with low oxygen pressure. To evaluate the effects of the exposure to intermittent chronic hypobaric hypoxia (ICHH) in nature on rat reproduction, a group of rats was alternately moved to a location at 3400 meters over sea level (moml) for 7 days and returned the subsequent week to sea level; this procedure was repeated six times. Hematological and reproductive parameters were measured and analyzed. At the end of the experimental protocol, hematocrit and hemoglobin concentrations were significantly greater in the ICHH group compared to the control group (Nx) (p < 0.05). The diameter of the seminiferous tubule and the height of the spermatogenic epithelium in ICHH rats presented a significant decrease in relation to Nx rats (p < 0.05). Consequently, the number of epididymal spermatozoa in the experimental animals decreased compared to normal rats, with no evidence of recovery after 84 days. The offspring of the different matings between normal and hypoxic animals decreased proportionally to hypoxia exposure. The low oxygen and the changes in testicular temperature homeostasis would provide a novel local mechanism to explain the decrease in sperm cell production and the reduced number of puppies born. The alterations of the reproductive parameters of the hypoxic female, plus testicular injuries and diminished sperm in males, result in a significant decrease in the reproductive activity of the animals.

  8. Enhanced Gas-Sensing Properties of the Hierarchical TiO₂ Hollow Microspheres with Exposed High-Energy {001} Crystal Facets.

    PubMed

    Yang, Yong; Liang, Yan; Wang, Guozhong; Liu, Liangliang; Yuan, Cailei; Yu, Ting; Li, Qinliang; Zeng, Fanyan; Gu, Gang

    2015-11-11

    Anatase hierarchical TiO2 with innovative designs (hollow microspheres with exposed high-energy {001} crystal facets, hollow microspheres without {001} crystal facets, and solid microspheres without {001} crystal facets) were synthesized via a one-pot hydrothermal method and characterized. Based on these materials, gas sensors were fabricated and used for gas-sensing tests. It was found that the sensor based on hierarchical TiO2 hollow microspheres with exposed high-energy {001} crystal facets exhibited enhanced acetone sensing properties compared to the sensors based on the other two materials due to the exposing of high-energy {001} crystal facets and special hierarchical hollow structure. First-principle calculations were performed to illustrate the sensing mechanism, which suggested that the adsorption process of acetone molecule on TiO2 surface was spontaneous, and the adsorption on high-energy {001} crystal facets would be more stable than that on the normally exposed {101} crystal facets. Further characterization indicated that the {001} surface was highly reactive for the adsorption of active oxygen species, which was also responsible for the enhanced sensing performance. The present studies revealed the crystal-facets-dependent gas-sensing properties of TiO2 and provided a new insight into improving the gas sensing performance by designing hierarchical hollow structure with special-crystal-facets exposure.

  9. Ethnic characterization of a population of children exposed to high doses of arsenic via drinking water and a possible correlation with metabolic processes.

    PubMed

    Bobillo, Cecilia; Navoni, Julio A; Olmos, Valentina; Merini, Luciano J; Villaamil Lepori, Edda; Corach, Daniel

    2014-01-01

    Because the ratio between the two major arsenic metabolites is related to the adverse health effects of arsenic, numerous studies have been performed to establish a relationship between the ability to metabolically detoxify arsenic and other variables, including exposure level, gender, age and ethnicity. Because ethnicity may play a key role and provide relevant information for heterogeneous populations, we characterized a group of 70 children from rural schools in the Argentinean provinces of Chaco and Santiago del Estero who were exposed to high levels of arsenic. We used genetic markers for maternal, paternal and bi-parental ancestry to achieve this goal. Our results demonstrate that the Amerindian maternal linages are present in 100% of the samples, whereas the Amerindian component transmitted through the paternal line is less than 10%. Informative markers for autosomal ancestry show a predominantly European ancestry, in which 37% of the samples contained between 90 and 99% European ancestry. The native American component ranged from 50 to 80% in 15.7% of the samples, and in all but four samples, the African component was less than 10%. Correlation analysis demonstrated that the ethnicity and the ratio of the excreted arsenic metabolites monomethyl arsenic and dimethyl arsenic are not associated, dismissing a relationship between ethnic origin and differential metabolism.

  10. Ethnic characterization of a population of children exposed to high doses of arsenic via drinking water and a possible correlation with metabolic processes

    PubMed Central

    Bobillo, Cecilia; Navoni, Julio A; Olmos, Valentina; Merini, Luciano J; Villaamil Lepori, Edda; Corach, Daniel

    2014-01-01

    Because the ratio between the two major arsenic metabolites is related to the adverse health effects of arsenic, numerous studies have been performed to establish a relationship between the ability to metabolically detoxify arsenic and other variables, including exposure level, gender, age and ethnicity. Because ethnicity may play a key role and provide relevant information for heterogeneous populations, we characterized a group of 70 children from rural schools in the Argentinean provinces of Chaco and Santiago del Estero who were exposed to high levels of arsenic. We used genetic markers for maternal, paternal and bi-parental ancestry to achieve this goal. Our results demonstrate that the Amerindian maternal linages are present in 100% of the samples, whereas the Amerindian component transmitted through the paternal line is less than 10%. Informative markers for autosomal ancestry show a predominantly European ancestry, in which 37% of the samples contained between 90 and 99% European ancestry. The native American component ranged from 50 to 80% in 15.7% of the samples, and in all but four samples, the African component was less than 10%. Correlation analysis demonstrated that the ethnicity and the ratio of the excreted arsenic metabolites monomethyl arsenic and dimethyl arsenic are not associated, dismissing a relationship between ethnic origin and differential metabolism. PMID:24596592

  11. Short Circuits or Superconductors? Effects of Group Composition on High-Achieving Students' Science Assessment Performance.

    ERIC Educational Resources Information Center

    Webb, Noreen M.; Nemer, Kariane Mari; Zuniga, Stephen

    2002-01-01

    Studied the effects of group ability composition (homogeneous versus heterogeneous) on group processes and outcomes for high-ability students completing science assessments. Results for 83 high ability students show the quality of group functioning serves as the strongest predictor of high-ability students' performance and explained much of the…

  12. High resolution photoelectron spectroscopy of clusters of Group V elements

    SciTech Connect

    Wang, Lai-sheng; Niu, B.; Lee, Y.T.; Shirley, D.A.

    1989-07-01

    High resolution HeI (580{angstrom}) photoelectron spectra of As{sub 2}, As{sub 4}, and P{sub 4} were obtained with a newly-built high temperature molecular beam source. Vibrational structure was resolved in the photoelectron spectra of the three cluster species. The Jahn-Teller effect is discussed for the {sup 2}E and {sup 2}T{sub 2} states of P{sub 4}{sup +} and As{sub 4}{sup +}. As a result of the Jahn-Teller effect, the {sup 2}E state splits into two bands, and the {sup 2}T{sub 2} state splits into three bands, in combination with the spin-orbit effect. It was observed that the {nu}{sub 2} normal vibrational mode was involved in the vibronic interaction of the {sup 2}E state, while both the {nu}{sub 2} and {nu}{sub 3} modes were active in the {sup 2}T{sub 2} state. 26 refs., 5 figs., 3 tabs.

  13. [Mercury and creatinine in urine of employees exposed to magnetic fields. A study of a group electrolysis-operators in Norzink A/S in Odda].

    PubMed

    Schmidt, F; Mannsåker

    1997-01-20

    The results described are based on a study of 26 male cell house employees. They were exposed to a combination of static magnetic fields (3-10 mT) and low frequency oscillating magnetic fields of variable frequency and strength for eight hours a day over a period of four weeks. Every fifth week was spent off work. Urine samples collected at the end of the four weeks of exposure were compared with samples collected at the end of the week off work. The results show that the cell house workers excreted significantly more mercury in their urine after exposure to magnetic fields (p = 0.01). The mercury/creatinine ratio was also significantly higher after exposure (p < 0.01). These results support findings by Schmidt in a study from 1992 when the levels of mercury and creatinine in the urine of cell house workers were compared with the levels in office personnel.

  14. 9 CFR 79.4 - Designation of scrapie-positive animals, high-risk animals, exposed animals, suspect animals...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... designated scrapie epidemiologist may conduct testing of animals if he or she determines such testing is... epidemiologist will select animals for testing in a manner that will provide a 95 percent confidence of detecting... lambed in the flock are available for testing, may limit the testing to all exposed and suspect...

  15. 9 CFR 79.4 - Designation of scrapie-positive animals, high-risk animals, exposed animals, suspect animals...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... designated scrapie epidemiologist may conduct testing of animals if he or she determines such testing is... epidemiologist will select animals for testing in a manner that will provide a 95 percent confidence of detecting... lambed in the flock are available for testing, may limit the testing to all exposed and suspect...

  16. 9 CFR 79.4 - Designation of scrapie-positive animals, high-risk animals, exposed animals, suspect animals...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... designated scrapie epidemiologist may conduct testing of animals if he or she determines such testing is... epidemiologist will select animals for testing in a manner that will provide a 95 percent confidence of detecting... lambed in the flock are available for testing, may limit the testing to all exposed and suspect...

  17. 9 CFR 79.4 - Designation of scrapie-positive animals, high-risk animals, exposed animals, suspect animals...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... designated scrapie epidemiologist may conduct testing of animals if he or she determines such testing is... epidemiologist will select animals for testing in a manner that will provide a 95 percent confidence of detecting... lambed in the flock are available for testing, may limit the testing to all exposed and suspect...

  18. 9 CFR 79.4 - Designation of scrapie-positive animals, high-risk animals, exposed animals, suspect animals...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... designated scrapie epidemiologist may conduct testing of animals if he or she determines such testing is... epidemiologist will select animals for testing in a manner that will provide a 95 percent confidence of detecting... lambed in the flock are available for testing, may limit the testing to all exposed and suspect...

  19. AIR POLLUTION EXPOSURE AND TELOMERE LENGTH IN HIGHLY EXPOSED SUBJECTS IN BEIJING, CHINA: A REPEATED-MEASURE STUDY

    PubMed Central

    Hou, Lifang; Wang, Sheng; Dou, Chang; Zhang, Xiao; Yu, Yue; Zheng, Yinan; Avula, Umakanth; Hoxha, Mirjam; Díaz, Anaité; McCracken, John; Barretta, Francesco; Marinelli, Barbara; Bertazzi, Pier Alberto; Schwartz, Joel; Baccarelli, Andrea A.

    2013-01-01

    Background Ambient particular matter (PM) exposure has been associated with short- and long-term effects on cardiovascular disease (CVD). Telomere length (TL) is a biomarker of CVD risk that is modified by inflammation and oxidative stress, two key pathways for PM effects. Whether PM exposure modifies TL is largely unexplored. Objectives To investigate effects of PM on blood TL in a highly-exposed population. Methods We measured blood TL in 120 blood samples from truck drivers and 120 blood samples from office workers in Beijing, China. We measured personal PM2.5 and Elemental Carbon (EC, a tracer of traffic particles) using light-weight monitors. Ambient PM10 was obtained from local monitoring stations. We used covariate-adjusted regression models to estimate percent changes in TL per an interquartile-range increase in exposure. Results Covariate-adjusted TL was higher in drivers (mean=0.87, 95%CI: 0.74; 1.03) than in office workers (mean=0.79, 95%CI: 0.67; 0.93; p=0.001). In all participants combined, TL increased in association with personal PM2.5 (+5.2%, 95%CI: 1.5; 9.1; p=0.007), personal EC (+4.9%, 95%CI: 1.2; 8.8; p=0.01), and ambient PM10 (+7.7%, 95%CI: 3.7; 11.9; p<0.001) on examination days. In contrast, average ambient PM10 over the 14 days before the examinations was significantly associated with shorter TL (−9.9%, 95%CI: −17.6; −1.5; p=0.02). Conclusions Short-term exposure to ambient PM is associated with increased blood TL, consistent with TL roles during acute inflammatory responses. Longer exposures may shorten TL as expected after prolonged pro-oxidant exposures. The observed TL alterations may participate in the biological pathways of short- and long-term PM effects. PMID:22871507

  20. Effects of dietary green tea polyphenol supplementation on the health of workers exposed to high-voltage power lines.

    PubMed

    Zhang, Yang; Zhang, Dan; Zhu, Baoyu; Zhang, He; Sun, Ye; Sun, Chengxun

    2016-09-01

    Although it has been several decades since the focus on the effect of extremely low frequency electromagnetic fields (ELF-EMF) of high-voltage power lines on human health, no consistent conclusion has been drawn. The present study aimed to investigate the change in oxidative stress after exposure to ELF-EMFs, and potential protective effects of green tea polyphenol supplementation (GTPS) on ELF-EMFs induced oxidative stress. A total of 867 subjects, including workers with or without exposure to ELF-EMFs of 110-420kV power lines, participated and were randomized into GTPS and placebo treatment groups. Oxidative stress and oxidative damage to DNA were assessed by urinary tests of 8-isoprostane and 8-OHdG. Significant increased urinary 8-isoprostane and 8-OHdG were observed in workers with ELF-EMFs exposure, which were diminished after 12 months of GTPS. No protective effects of GTPS on oxidative stress and oxidative damage to DNA were observed after three months of GTPS withdraw. We found a negative impact of high-voltage power lines on the health of workers. Long-term GTPS could be an efficient protection against the health issues induced by high-voltage power lines. PMID:27490209

  1. Effects of dietary green tea polyphenol supplementation on the health of workers exposed to high-voltage power lines.

    PubMed

    Zhang, Yang; Zhang, Dan; Zhu, Baoyu; Zhang, He; Sun, Ye; Sun, Chengxun

    2016-09-01

    Although it has been several decades since the focus on the effect of extremely low frequency electromagnetic fields (ELF-EMF) of high-voltage power lines on human health, no consistent conclusion has been drawn. The present study aimed to investigate the change in oxidative stress after exposure to ELF-EMFs, and potential protective effects of green tea polyphenol supplementation (GTPS) on ELF-EMFs induced oxidative stress. A total of 867 subjects, including workers with or without exposure to ELF-EMFs of 110-420kV power lines, participated and were randomized into GTPS and placebo treatment groups. Oxidative stress and oxidative damage to DNA were assessed by urinary tests of 8-isoprostane and 8-OHdG. Significant increased urinary 8-isoprostane and 8-OHdG were observed in workers with ELF-EMFs exposure, which were diminished after 12 months of GTPS. No protective effects of GTPS on oxidative stress and oxidative damage to DNA were observed after three months of GTPS withdraw. We found a negative impact of high-voltage power lines on the health of workers. Long-term GTPS could be an efficient protection against the health issues induced by high-voltage power lines.

  2. One size does not fit all: HIV testing preferences differ among high-risk groups in Northern Tanzania

    PubMed Central

    Ostermann, Jan; Njau, Bernard; Mtuy, Tara; Brown, Derek S.; Mühlbacher, Axel; Thielman, Nathan

    2014-01-01

    In order to maximize the effectiveness of “Seek, Test, and Treat” strategies for curbing the HIV epidemic, new approaches are needed to increase the uptake of HIV testing services, particularly among high-risk groups. Low HIV testing rates among such groups suggests that current testing services may not align well with the testing preferences of these populations. Female bar workers and male mountain porters have been identified as two important high-risk groups in the Kilimanjaro Region of Tanzania. We used conventional survey methods and a Discrete Choice Experiment (DCE), a preference elicitation method increasingly applied by economists and policy makers to inform health policy and services, to analyze trade-offs made by individuals and quantify preferences for HIV testing services. Compared to 486 randomly selected community members, 162 female bar workers and 194 male Kilimanjaro porters reported 2 to 3 times as many lifetime sexual partners (p<0.001), but similar numbers of lifetime HIV tests (median 1–2 across all groups). Bivariate descriptive statistics were used to analyze differences in survey responses across groups. For the DCE, participants’ stated choices across 11,178 hypothetical HIV testing scenarios (322 female and 299 male participants × 9 choice tasks × 2 alternatives) were analyzed using gender-specific mixed logit models. Direct assessments and the DCE data demonstrated that barworkers were less likely to prefer home testing and were more concerned about disclosure issues compared with their community counterparts. Male porters preferred testing in venues where antiretroviral therapy was readily available. Both high-risk groups were less averse to traveling longer distances to test compared to their community counterparts. These results expose systematic differences in HIV testing preferences across high-risk populations compared to their community peers. Tailoring testing options to the preferences of high-risk populations should

  3. The epigenetic effects of a high prenatal folate intake in male mouse fetuses exposed in utero to arsenic

    SciTech Connect

    Tsang, Verne; Fry, Rebecca C.; Niculescu, Mihai D.; Rager, Julia E.; Saunders, Jesse; Paul, David S.; Zeisel, Steven H.; Waalkes, Michael P.; Stýblo, Miroslav; Drobná, Zuzana

    2012-11-01

    Inorganic arsenic (iAs) is a complete transplacental carcinogen in mice. Previous studies have demonstrated that in utero exposure to iAs promotes cancer in adult mouse offspring, possibly acting through epigenetic mechanisms. Humans and rodents enzymatically convert iAs to its methylated metabolites. This reaction requires S-adenosylmethionine (SAM) as methyl group donor. SAM is also required for DNA methylation. Supplementation with folate, a major dietary source of methyl groups for SAM synthesis, has been shown to modify iAs metabolism and the adverse effects of iAs exposure. However, effects of gestational folate supplementation on iAs metabolism and fetal DNA methylation have never been thoroughly examined. In the present study, pregnant CD1 mice were fed control (i.e. normal folate, or 2.2 mg/kg) or high folate diet (11 mg/kg) from gestational day (GD) 5 to 18 and drank water with 0 or 85 ppm of As (as arsenite) from GD8 to 18. The exposure to iAs significantly decreased body weight of GD18 fetuses and increased both SAM and S-adenosylhomocysteine (SAH) concentrations in fetal livers. High folate intake lowered the burden of total arsenic in maternal livers but did not prevent the effects of iAs exposure on fetal weight or hepatic SAM and SAH concentrations. In fact, combined folate-iAs exposure caused further significant body weight reduction. Notably, iAs exposure alone had little effect on DNA methylation in fetal livers. In contrast, the combined folate-iAs exposure changed the CpG island methylation in 2,931 genes, including genes known to be imprinted. Most of these genes were associated with neurodevelopment, cancer, cell cycle, and signaling networks. The canonical Wnt-signaling pathway, which regulates fetal development, was among the most affected biological pathways. Taken together, our results suggest that a combined in utero exposure to iAs and a high folate intake may adversely influence DNA methylation profiles and weight of fetuses

  4. Participation of gap junction communication in potentially lethal damage repair and DNA damage in human fibroblasts exposed to low- or high-LET radiation

    PubMed Central

    Autsavapromporn, Narongchai; Suzuki, Masao; Plante, Ianik; Liu, Cuihua; Uchihori, Yukio; Hei, Tom K.; Azzam, Edouard I.; Murakami, Takeshi

    2014-01-01

    Existing research has not fully explained how different types of ionizing radiation (IR) modulate the responses of cell populations or tissues. In our previous work, we showed that gap junction intercellular communication (GJIC) mediates the propagation of stressful effects among irradiated cells exposed to high linear energy transfer (LET) radiations, in which almost every cells is traversed by an IR track. In the present study, we conducted an in-depth study of the role of GJIC in modulating the repair of potentially lethal damage (PLDR) and micronuclei formation in cells exposed to low- or high-LET IR. Confluent human fibroblasts were exposed in the presence or absence of a gap junction inhibitor to 200 kV X rays (LET ∼ 1.7 keV/µm), carbon ions (LET ∼ 76 keV/µm), silicon ions (LET ∼ 113 keV/µm) or iron ions (LET ∼ 400 keV/µm) that resulted in isosurvival levels. The fibroblasts were incubated for various times at 37 °C. As expected, high-LET IR were more effective than were low-LET X rays at killing cells and damaging DNA shortly after irradiation. However, when cells were held in a confluent state for several hours, PLDR associated with a reduction in DNA damage, occurred only in cells exposed to X rays. Interestingly, inhibition of GJIC eliminated the enhancement of toxic effects, which resulted in an increase of cell survival and reduction in the level of micronucleus formation in cells exposed to high, but not in those exposed to low-LET IR. The experiment shows that gap-junction communication plays an important role in the propagation of stressful effects among irradiated cells exposed to high-LET IR while GJIC has only a minimal effect on PLDR and DNA damage following low-LET irradiation. Together, our results show that PLDR and induction of DNA damage clearly depend on gap-junction communication and radiation quality. PMID:23867854

  5. Highly enhanced acetone sensing performances of porous and single crystalline ZnO nanosheets: high percentage of exposed (100) facets working together with surface modification with Pd nanoparticles.

    PubMed

    Xiao, Yuanhua; Lu, Lingzhen; Zhang, Aiqin; Zhang, Yonghui; Sun, Li; Huo, Lei; Li, Feng

    2012-08-01

    Porous and single crystalline ZnO nanosheets, which were synthesized by annealing hydrozincite Zn(5)(CO(3))(2)(OH)(6) nanoplates produced with a water/ethylene glycol solvothermal method, are used as building blocks to construct functional Pd-ZnO nanoarchitectures together with Pd nanoparticles based on a self-assembly approach. Chemical sensing performances of the ZnO nanosheets were investigated carefully before and after their surface modification with Pd nanoparticles. It was found that the chemical sensors made with porous ZnO nanosheets exhibit high selectivity and quick response for detecting acetone, because of the 2D ZnO nanocrystals exposed in (100) facets at high percentage. The performances of the acetone sensors can be further improved dramatically, after the surfaces of ZnO nanosheets are modified with Pd nanoparticles. Novel acetone sensors with enhanced response, selectivity and stability have been fabricated successfully by using nanoarchitectures consisting of ZnO nanosheets and Pd nanoparticles.

  6. Ghosts of thermal past: reef fish exposed to historic high temperatures have heightened stress response to further stressors

    NASA Astrophysics Data System (ADS)

    Mills, S. C.; Beldade, R.; Chabanet, P.; Bigot, L.; O'Donnell, J. L.; Bernardi, G.

    2015-12-01

    Individual exposure to stressors can induce changes in physiological stress responses through modulation of the hypothalamic-pituitary-interrenal (HPI) axis. Despite theoretical predictions, little is known about how individuals will respond to unpredictable short-lived stressors, such as thermal events. We examine the primary neuroendocrine response of coral reef fish populations from the Îles Eparses rarely exposed to anthropogenic stress, but that experienced different thermal histories. Skunk anemonefish, Amphiprion akallopisos, showed different cortisol responses to a generic stressor between islands, but not along a latitudinal gradient. Those populations previously exposed to higher maximum temperatures showed greater responses of their HPI axis. Archive data reveal thermal stressor events occur every 1.92-6 yr, suggesting that modifications to the HPI axis could be adaptive. Our results highlight the potential for adaptation of the HPI axis in coral reef fish in response to a climate-induced thermal stressor.

  7. High and Low Consensus Groups: A Content and Relational Interaction Analysis.

    ERIC Educational Resources Information Center

    DeStephen, Rolayne S.

    1983-01-01

    Analyzed the complete interaction of high and low consensus groups in a basic small group course. Interaction analysis indicated that both the relational and content levels of communication are significantly different for high versus low consensus groups. The conclusion that increased feedback leads to decision satisfaction was confirmed. (JAC)

  8. Does Homogeneous Ability Grouping for High School Honors English Instruction Benefit the High Achiever?

    ERIC Educational Resources Information Center

    Hostetter, Douglas Paul

    2013-01-01

    Public schools are examining their policies and instructional practices to address the achievement gap exposed by the reporting requirements of NCLB (Wenglinski, 2004). As accountability measures and stakes rise, there is a call for an improved use of scientific evidence to inform educational policymaking (Wiseman, 2010). In terms of the…

  9. Effect of high-fructose and high-fat diets on pulmonary sensitivity, motor activity, and body composition of brown Norway rats exposed to ozone.

    PubMed

    Gordon, C J; Phillips, P M; Johnstone, A F M; Beasley, T E; Ledbetter, A D; Schladweiler, M C; Snow, S J; Kodavanti, U P

    2016-04-01

    Diet-induced obesity has been suggested to lead to increased susceptibility to air pollutants such as ozone (O3); however, there is little experimental evidence. Thirty day old male and female Brown Norway rats were fed a normal, high-fructose or high-fat diet for 12 weeks and then exposed to O3 (acute - air or 0.8 ppm O3 for 5 h, or subacute - air or 0.8 ppm O3 for 5 h/d 1 d/week for 4 weeks). Body composition was measured non-invasively using NMR. Ventilatory parameters and exploratory behavior were measured after the third week of subacute exposure. Bronchoalveolar lavage fluid (BALF) and blood chemistry data were collected 18 h after acute O3 and 18 h after the fourth week of subacute O3. The diets led to increased body fat in male but not female rats. O3-induced changes in ventilatory function were either unaffected or improved with the fructose and fat diets. O3-induced reduction in exploratory behavior was attenuated with fructose and fat diets in males and partially in females. O3 led to a significant decrease in body fat of males fed control diet but not the fructose or fat diet. O3 led to significant increases in BALF eosinophils, increase in albumin, and reductions in macrophages. Female rats appeared to be more affected than males to O3 regardless of diet. Overall, treatment with high-fructose and high-fat diets attenuated some O3 induced effects on pulmonary function, behavior, and metabolism. Exacerbation of toxicity was observed less frequently. PMID:27092583

  10. The Epigenetic Effects of a High Prenatal Folate Intake in Male Mouse Fetuses Exposed In Utero to Arsenic

    PubMed Central

    Tsang, Verne; Fry, Rebecca C.; Niculescu, Mihai D.; Rager, Julia E.; Saunders, Jesse; Paul, David S.; Zeisel, Steven H.; Waalkes, Michael P.; Stýblo, Miroslav; Drobná, Zuzana

    2012-01-01

    Inorganic arsenic (iAs) is a complete transplacental carcinogen in mice. Previous studies have demonstrated that in utero exposure to iAs promotes cancer in adult mouse offspring, possibly acting through epigenetic mechanisms. Humans and rodents enzymatically convert iAs to its methylated metabolites. This reaction requires S-adenosylmethionine (SAM) as methyl group donor. SAM is also required for DNA methylation. Supplementation with folate, a major dietary source of methyl groups for SAM synthesis, has been shown to modify iAs metabolism and the adverse effects of iAs exposure. However, effects of gestational folate supplementation on iAs metabolism and fetal DNA methylation have never been thoroughly examined. In the present study, pregnant CD1 mice were fed control (i.e. normal folate, or 2.2 mg/kg) or high folate diet (11 mg/kg) from gestational day (GD) 5 to 18 and drank water with 0 or 85 ppm of As (as arsenite) from GD8 to 18. The exposure to iAs significantly decreased body weight of GD18 fetuses and increased both SAM and S-adenosylhomocysteine (SAH) concentrations in fetal livers. High folate intake lowered the burden of total arsenic in maternal livers but did not prevent the effects of iAs exposure on fetal weight or hepatic SAM and SAH concentrations. In fact, combined folate-iAs exposure caused further significant body weight reduction. Notably, iAs exposure alone had little effect on DNA methylation in fetal livers. In contrast, the combined folate-iAs exposure changed the CpG island methylation in 2,931 genes, including genes known to be imprinted. Most of these genes were associated with neurodevelopment, cancer, cell cycle, and signaling networks. The canonical Wnt-signaling pathway, which regulates fetal development, was among the most affected biological pathways. Taken together, our results suggest that a combined in utero exposure to iAs and a high folate intake may adversely influence DNA methylation profiles and weight of fetuses

  11. Effects of Cooperative Grouping on Stoichiometric Problem Solving in High School Chemistry.

    ERIC Educational Resources Information Center

    Tingle, Joy B.; Good, Ron

    1990-01-01

    Determined was the effect that cooperative groups heterogeneously based on proportional reasoning ability have on problem solving in regular and honors high school chemistry. Characteristics of successful and unsuccessful problem solvers individually and in groups are discussed. (KR)

  12. Prevalence of HIV antibody in high and low risk groups in England. Public Health Laboratory Service Working Group.

    PubMed Central

    1989-01-01

    Most studies of the spread of HIV infection have centred on homosexuals and intravenous drug users. To estimate the extent of infection in different groups, including heterosexuals, the prevalence of HIV antibody was studied in 34,222 subjects tested with consent between October 1986 and December 1987 in England. These included subjects in high risk groups for HIV infection, heterosexuals with partners in the high risk groups and heterosexuals with multiple partners or with no identifiable risk factors. The prevalence was highest in homosexual or bisexual men in London (15.1%; 213/1412), being 4.0% (146/3607) outside London. The yearly incidence of infection in 632 homosexual or bisexual men without HIV antibody when retested during the study period was 3%. Among intravenous drug users the prevalence of HIV antibody was 5.7% (36/633) in London and 1.5% (39/2562) outside. Of 3272 heterosexual subjects tested, whose partner was in a risk group, eight of 515 (1.6%) in London and six of 2757 (0.2%) outside were positive for the antibody. Among 20,455 heterosexuals with a history of multiple partners or with no declared risk, only six subjects with HIV antibody were identified, two of whom had been infected abroad. Heterosexual spread of infection in England is evidently still largely confined to subjects whose partner has an identifiable risk. PMID:2495048

  13. Eryptosis in lead-exposed workers

    SciTech Connect

    Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

    2014-12-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca{sup 2+}]{sub i} and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca{sup 2+}], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers

  14. Surface vibration and nearby cavitation of an ex vivo bovine femur exposed to high intensity focused ultrasound.

    PubMed

    Zhang, Siyuan; Li, Chong; Yin, Hui; Wang, Supin; Wan, Mingxi

    2013-08-01

    The acoustic pressure distribution, thermal ablation, and sonochemiluminescence (SCL) generated by cavitation near the surface of an ex vivo bovine femur were investigated at normal and oblique incidences of high intensity focused ultrasound (HIFU), as were the characteristics of bone surface vibrations. The acoustic pressure at the HIFU focus, the width of thermal ablation, and the SCL intensity in the pre-focal region were 1.3 MPa, 7 mm, and 454 electrons, respectively, in the control group at normal incidence, and they respectively increased to 1.5 MPa, 12 mm and 968 electrons in the presence of the bone. At oblique incidence from the left, the acoustic pressure at 3 mm to the right of the HIFU focus was 0.6 MPa and decreased to 0.4 MPa at 3 mm to the left of the focus. The thermal ablation was 20 mm in width and extended along the front surface of the bone to the right of the HIFU focus. The SCL intensity on the right of the HIFU focus was 394 electrons and was 362 electrons on the left. The presence of bone would directionally change the spatial distribution of acoustic pressure, thermal and cavitation effects for oblique incidence of HIFU.

  15. Blood B Lymphocyte Stimulator (BLyS)/BAFF levels may reflect natural immunity to HIV in highly exposed uninfected Beninese Commercial Sex Workers.

    PubMed

    Sabourin-Poirier, Catherine; Fourcade, Lyvia; Chagnon-Choquet, Josiane; Labbé, Annie-Claude; Alary, Michel; Guédou, Fernand; Poudrier, Johanne; Roger, Michel

    2016-01-01

    We have previously shown that excess B lymphocyte Stimulator (BLyS)/BAFF in plasma and on surface of blood dendritic cells (DC) of HIV-infected progressors coincides with B-cell dysregulations and increased frequencies of "precursor" innate marginal zone (MZ)-like B-cells. In contrast, both blood BLyS levels and frequencies of this population remained unaltered in HIV elite-controllers. Based on these observations, we hypothesized that control of BLyS and innate B-cell status could be associated with natural immunity against HIV infection. Therefore, we assessed blood BLyS levels and B-cell status in HIV highly-exposed commercial sex workers (CSWs) from Benin. We found blood BLyS levels of HIV-uninfected CSWs were lower than those observed in both HIV-infected CSW and HIV-uninfected non-CSW groups. Furthermore, levels of BLyS expression on blood T-cells and monocytes were lower in HIV-uninfected CSWs when compared to HIV-infected CSWs, but higher than those observed for HIV-uninfected non-CSWs. Concomitantly, HIV-infected CSWs presented a dysregulated blood B-cell compartment, characterized by increased total IgG1, increased frequencies of populations presenting immature and/or innate profiles and a higher ratio of IgG(+)/IgA(+) plasmablasts. In contrast, relatively low levels of BLyS in the blood of HIV-uninfected CSWs coincided with a rather preserved B-cell compartment. PMID:27561453

  16. Blood B Lymphocyte Stimulator (BLyS)/BAFF levels may reflect natural immunity to HIV in highly exposed uninfected Beninese Commercial Sex Workers

    PubMed Central

    Sabourin-Poirier, Catherine; Fourcade, Lyvia; Chagnon-Choquet, Josiane; Labbé, Annie-Claude; Alary, Michel; Guédou, Fernand; Poudrier, Johanne; Roger, Michel

    2016-01-01

    We have previously shown that excess B lymphocyte Stimulator (BLyS)/BAFF in plasma and on surface of blood dendritic cells (DC) of HIV-infected progressors coincides with B-cell dysregulations and increased frequencies of “precursor” innate marginal zone (MZ)-like B-cells. In contrast, both blood BLyS levels and frequencies of this population remained unaltered in HIV elite-controllers. Based on these observations, we hypothesized that control of BLyS and innate B-cell status could be associated with natural immunity against HIV infection. Therefore, we assessed blood BLyS levels and B-cell status in HIV highly-exposed commercial sex workers (CSWs) from Benin. We found blood BLyS levels of HIV-uninfected CSWs were lower than those observed in both HIV-infected CSW and HIV-uninfected non-CSW groups. Furthermore, levels of BLyS expression on blood T-cells and monocytes were lower in HIV-uninfected CSWs when compared to HIV-infected CSWs, but higher than those observed for HIV-uninfected non-CSWs. Concomitantly, HIV-infected CSWs presented a dysregulated blood B-cell compartment, characterized by increased total IgG1, increased frequencies of populations presenting immature and/or innate profiles and a higher ratio of IgG+/IgA+ plasmablasts. In contrast, relatively low levels of BLyS in the blood of HIV-uninfected CSWs coincided with a rather preserved B-cell compartment. PMID:27561453

  17. Overexpression of DJ-1 reduces oxidative stress and attenuates hypoxia/reoxygenation injury in NRK-52E cells exposed to high glucose

    PubMed Central

    Shen, Zi-Ying; Sun, Qian; Xia, Zhong-Yuan; Meng, Qing-Tao; Lei, Shao-Qing; Zhao, Bo; Tang, Ling-Hua; Xue, Rui; Chen, Rong

    2016-01-01

    Patients with diabetes are more vulnerable to renal ischemia/reperfusion (I/R) injury, which is implicated in hyperglycemia-induced oxidative stress. We previously reported that the hyperglycemia-induced inhibition of DJ-1, a novel oncogene that exhibits potent antioxidant activity, is implicated in the severity of myocardial I/R injury. In the present study, we aimed to explore the role of DJ-1 in hypoxia/reoxygenation (H/R) injury in renal cells exposed to high glucose (HG). For this purpose, NRK-52E cells were exposed to HG (30 mM) for 48 h and then exposed to hypoxia for 4 h and reoxygenation for 2 h, which significantly decreased cell viability and superoxide dismutase (SOD) activity, and increased the malondialdehyde (MDA) content, accompanied by a decrease in DJ-1 protein expression. The overexpression of DJ-1 by transfection with a DJ-1 overexpression plasmid exerted protective effects against HG-induced H/R injury, as evidenced by increased CCK-8 levels and SOD activity, the decreased release of lactate dehydrogenase (LDH) and the decreased MDA content, and increased nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase-1 (HO-1) expression. Similar effects were observed following treatment with the antioxidant, N-acetylcysteine. These results suggest that the overexpression of DJ-1 reduces oxidative stress and attenuates H/R injury in NRK-52E cells exposed to HG. PMID:27430285

  18. Inflight resistance measurement on high-T(sub c) superconducting thin films exposed to orbital atomic oxygen on CONCAP-2 (STS-46)

    NASA Technical Reports Server (NTRS)

    Gregory, J. C.; Raiker, G. N.; Bijvoet, J. A.; Nerren, P. D.; Sutherland, W. T.; Mogro-Camperso, A.; Turner, L. G.; Kwok, Hoi; Raistrick, I. D.; Cross, J. B.

    1995-01-01

    In 1992, UAH (University of Alabama in Huntsville) conducted a unique experiment on STS-46 in which YBa2Cu3O7 (commonly known as '1-2-3' superconductor) high-T(c) superconducting thin film samples prepared at three different laboratories were exposed to 5 eV atomic oxygen in low Earth orbit on the ambient and 320 C hot plate during the first flight of the CONCAP-2 (Complex Autonomous Payload) experiment carrier. The resistance of the thin films was measured in flight during the atomic oxygen exposure and heating cycle. Superconducting properties were measured in the laboratory before and after the flight by the individual experimenters. Films with good superconducting properties, and which were exposed to the oxygen flux, survived the flight including those heated to 320 C (600 K) with properties essentially unchanged, while other samples which were heated but not exposed to oxygen were degraded. The properties of other flight controls held at ambient temperature appear unchanged and indistinguishable from those of ground controls, whether exposed to oxygen or not.

  19. Student Counseling Groups in Senior High School Settings: An Evaluation of Outcome.

    ERIC Educational Resources Information Center

    Henry, Susan E.; Kilmann, Peter R.

    1979-01-01

    This paper reviewed the studies which evaluated counseling groups in senior high school settings. A methodological evaluation was conducted within four areas: subjects, counselors, treatment, and outcome criteria. Overall, behavioral and directive groups achieved greater success than nondirective or client-centered groups. (Author)

  20. Influences on Member Assimilation in Work Groups in High-Reliability Organizations: A Multilevel Analysis

    ERIC Educational Resources Information Center

    Myers, Karen Kroman; McPhee, Robert D.

    2006-01-01

    This multilevel investigation examined the effect of group interaction and its influence on individual-level membership variables and group assimilation. The study is based on a model of group socialization developed by Moreland and Levine (1982) and was modified in this study to investigate the development and maintenance of highly interdependent…

  1. ABC's of Group Work: Building Community in Schools. A Workbook for High School and College.

    ERIC Educational Resources Information Center

    Ellsworth, J'Anne

    This workbook takes the theories and research from many disciplines and experts and combines them into short, easy-to-assimilate units that facilitate group participation at the high school and college level. Group skills are presented as 26 distinctive lessons. Each lesson begins with an explanation page, then an activity page gives the group an…

  2. Combined effects of crystallography, heat treatment and surface polishing on blistering in tungsten exposed to high-flux deuterium plasma

    NASA Astrophysics Data System (ADS)

    Zayachuk, Y.; Tanyeli, I.; Van Boxel, S.; Bystrov, K.; Morgan, T. W.; Roberts, S. G.

    2016-08-01

    For tungsten exposed to low-energy hydrogen-plasmas, it has been thought that grains with < \\text{1} \\text{1} \\text{1}> surface normal are most susceptible to blistering while those with < \\text{0} \\text{0} \\text{1}> surface normal are virtually impervious to it. Here, we report results showing that non-uniformity of blister distribution depends on the state of the surface due to polishing. In electrochemically polished material blisters appear on the grains with all orientations, while in mechanically polished material blister-free areas associated with particular orientations emerge. On the other hand, blistering is shown to have a strong dependence on the level of deformation within particular grains in partially recrystallized material.

  3. RET/PTC rearrangements preferentially occurred in papillary thyroid cancer among atomic bomb survivors exposed to high radiation dose.

    PubMed

    Hamatani, Kiyohiro; Eguchi, Hidetaka; Ito, Reiko; Mukai, Mayumi; Takahashi, Keiko; Taga, Masataka; Imai, Kazue; Cologne, John; Soda, Midori; Arihiro, Koji; Fujihara, Megumu; Abe, Kuniko; Hayashi, Tomayoshi; Nakashima, Masahiro; Sekine, Ichiro; Yasui, Wataru; Hayashi, Yuzo; Nakachi, Kei

    2008-09-01

    A major early event in papillary thyroid carcinogenesis is constitutive activation of the mitogen-activated protein kinase signaling pathway caused by alterations of a single gene, typically rearrangements of the RET and NTRK1 genes or point mutations in the BRAF and RAS genes. In childhood papillary thyroid cancer, regardless of history of radiation exposure, RET/PTC rearrangements are a major event. Conversely, in adult-onset papillary thyroid cancer among the general population, the most common molecular event is BRAF(V600E) point mutation, not RET/PTC rearrangements. To clarify which gene alteration, chromosome aberration, or point mutation preferentially occurs in radiation-associated adult-onset papillary thyroid cancer, we have performed molecular analyses on RET/PTC rearrangements and BRAF(V600E) mutation in 71 papillary thyroid cancer cases among atomic bomb survivors (including 21 cases not exposed to atomic bomb radiation), in relation to radiation dose as well as time elapsed since atomic bomb radiation exposure. RET/PTC rearrangements showed significantly increased frequency with increased radiation dose (P(trend) = 0.002). In contrast, BRAF(V600E) mutation was less frequent in cases exposed to higher radiation dose (P(trend) < 0.001). Papillary thyroid cancer subjects harboring RET/PTC rearrangements developed this cancer earlier than did cases with BRAF(V600E) mutation (P = 0.03). These findings were confirmed by multivariate logistic regression analysis. These results suggest that RET/PTC rearrangements play an important role in radiation-associated thyroid carcinogenesis.

  4. Increased oxidative stress and toxicity in ADH and CYP2E1 overexpressing human hepatoma VL-17A cells exposed to high glucose.

    PubMed

    Chandrasekaran, Karthikeyan; Swaminathan, Kavitha; Kumar, S Mathan; Clemens, Dahn L; Dey, Aparajita

    2012-05-01

    High glucose mediated oxidative stress and cell death is a well documented phenomenon. Using VL-17A cells which are HepG2 cells over-expressing alcohol dehydrogenase (ADH) and cytochrome P450 2E1 (CYP2E1) and control HepG2 cells, the association of ADH and CYP2E1 with high glucose mediated oxidative stress and toxicity in liver cells was investigated. Cell viability was measured and apoptosis or necrosis was determined through caspase-3 activity, Annexin V-propidium iodide staining and detecting decreases in mitochondrial membrane potential. Reactive oxygen species, lipid peroxidation and the formation of advanced glycated-end products were assessed. The levels of several antioxidants which included glutathione, glutathione peroxidase, catalase and superoxide dismutase were altered in high glucose treated VL-17A cells. Greater toxicity was observed in VL-17A cells exposed to high glucose when compared to HepG2 cells. Oxidative stress parameters were greatly increased in high glucose exposed VL-17A cells and apoptotic cell death was observed. Inhibition of CYP2E1 or caspase 3 or addition of the antioxidant trolox led to significant decreases in high glucose mediated oxidative stress and toxicity. Thus, the over-expression of ADH and CYP2E1 in liver cells is associated with increased high glucose mediated oxidative stress and toxicity.

  5. Victimization of high performers: the roles of envy and work group identification.

    PubMed

    Kim, Eugene; Glomb, Theresa M

    2014-07-01

    Drawing from victim precipitation, social comparison, and identity theories, this study develops and tests an integrative model of the victimization of high-performing employees. We examine envy as an explanatory mechanism of the victimization of high performers from fellow group members and propose work group identification as a moderator of this envy mechanism. Study 1, in a sample of 4,874 university staff employees in 339 work groups, supports the proposition that high performers are more likely to be targets of victimization. In Study 2, multisource data collected at 2 time points (217 employees in 67 work groups in 3 organizations), supports the proposition that high performers are more likely to be targets of victimization because of fellow group members' envy, and work group identification mitigates the mediated relationship.

  6. 'Bounce' Exposed

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This approximate true-color image, acquired by the Mars Exploration Rover Opportunity's panoramic camera, features the hole ground by the rover's rock abrasion tool into 'Bounce' rock. The hole measures approximately 35 centimeters (14 inches) long and 10 centimeters (4 inches) high. The depression measures 6.44 millimeters (0.25 inch) deep and about 4.5 centimeters (1.7 inches) across. The grinding procedure took place on the rover's 66th sol on Mars and lasted 2 hours and 15 minutes. A combination of limited solar power, added safety measures and the rock's jagged texture led the rock abrasion tool team to set more aggressive grinding parameters to ensure that the end result was a full circle, suitable for a thorough read from the rover's spectrometers.

    Bounce's outer ring consists of the cuttings from the rock, pushed out by the brushes on the grinding instrument. The small impressions filled with red dust on the outer ring were caused by the instrument's contact mechanism, which serves to stabilize it while grinding.

    This image was created using the panoramic camera's blue, green and red filters.

  7. Solvothermal synthesis of nanostructured BiVO4 with highly exposed (0 1 0) facets and enhanced sunlight-driven photocatalytic properties

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Zhao, Guosheng; An, Maozhong; Chang, Limin

    2015-12-01

    Nanostructured monoclinic BiVO4 (m-BiVO4) sheets with highly exposed (0 1 0) facets was synthesized by a surfactant-free solvothermal route, during which glycerol aqueous solution was first used as solvent. The effects of volume fraction of glycerol aqueous solution and pH value in the solvothermal process have been studied by means of the XRD, SEM, TEM, HRTEM, EDS, BET, FTIR, and UV-vis techniques. The adoption of glycerol is shown to influence preferential crystal growth of BiVO4 along its (0 1 0) facets to further act as the directing agent, as well as the morphology and crystalline structure. Moreover, the pH value also has significant influence on the crystal growth direction and morphology of the products. The sheet-like m-BiVO4 sample with highly exposed (0 1 0) facets could be obtained by using 15% glycerol aqueous solution as solvent at pH 6, and exhibited the best sunlight-driven photocatalytic performance for methylene blue degradation. It is concluded that the excellent photocatalytic activity on m-BiVO4 can be attributed to the preferentially exposed surfaces of the (0 1 0) facets which increases the separation efficiency of photogenerated electron-hole pairs and improves the surface active sites.

  8. Hierarchical LiMn2O4 Hollow Cubes with Exposed {111} Planes as High-Power Cathodes for Lithium-Ion Batteries.

    PubMed

    Wu, Yu; Cao, Chuanbao; Zhang, Junting; Wang, Lin; Ma, Xilan; Xu, Xingyan

    2016-08-01

    Hierarchical LiMn2O4 hollow cubes with exposed {111} planes have been synthesized using cube-shaped MnCO3 precursors, which are fabricated through a facile co-precipitation reaction. Without surface modification, the as-prepared LiMn2O4 exhibits excellent cyclability and superior rate capability. Surprisingly, even over 70% of primal discharge capacity can be maintained for up to 1000 cycles at 50 C, and with only about 72 s of discharge time the as-prepared materials can deliver initial discharge capacity of 96.5 mA h g(-1). What is more, the materials have 98.4% and 90.7% capacity retentions for up to 100 cycles at 5 C under the temperatures of 25 and 60 °C, respectively. The superior electrochemical performance can be attributed to the unique hierarchical and interior hollow structure, exposed {111} planes, and high-quality crystallinity.

  9. Na2 Ti6 O13 Nanorods with Dominant Large Interlayer Spacing Exposed Facet for High-Performance Na-Ion Batteries.

    PubMed

    Cao, Kangzhe; Jiao, Lifang; Pang, Wei Kong; Liu, Huiqiao; Zhou, Tengfei; Guo, Zaiping; Wang, Yijing; Yuan, Huatang

    2016-06-01

    As the delegate of tunnel structure sodium titanates, Na2 Ti6 O13 nanorods with dominant large interlayer spacing exposed facet are prepared. The exposed large interlayers provide facile channels for Na(+) insertion and extraction when this material is used as anode for Na-ion batteries (NIBs). After an activation process, this NIB anode achieves a high specific capacity (a capacity of 172 mAh g(-1) at 0.1 A g(-1) ) and outstanding cycling stability (a capacity of 109 mAh g(-1) after 2800 cycles at 1 A g(-1) ), showing its promising application on large-scale energy storage systems. Furthermore, the electrochemical and structural characterization reveals that the expanded interlayer spacings should be in charge of the activation process, including the enhanced kinetics, the lowered apparent activation energy, and the increased capacity. PMID:27095282

  10. Hierarchical LiMn2O4 Hollow Cubes with Exposed {111} Planes as High-Power Cathodes for Lithium-Ion Batteries.

    PubMed

    Wu, Yu; Cao, Chuanbao; Zhang, Junting; Wang, Lin; Ma, Xilan; Xu, Xingyan

    2016-08-01

    Hierarchical LiMn2O4 hollow cubes with exposed {111} planes have been synthesized using cube-shaped MnCO3 precursors, which are fabricated through a facile co-precipitation reaction. Without surface modification, the as-prepared LiMn2O4 exhibits excellent cyclability and superior rate capability. Surprisingly, even over 70% of primal discharge capacity can be maintained for up to 1000 cycles at 50 C, and with only about 72 s of discharge time the as-prepared materials can deliver initial discharge capacity of 96.5 mA h g(-1). What is more, the materials have 98.4% and 90.7% capacity retentions for up to 100 cycles at 5 C under the temperatures of 25 and 60 °C, respectively. The superior electrochemical performance can be attributed to the unique hierarchical and interior hollow structure, exposed {111} planes, and high-quality crystallinity. PMID:27400369

  11. Grain boundary depletion and migration during selective oxidation of Cr in a Ni-5Cr binary alloy exposed to high-temperature hydrogenated water

    SciTech Connect

    Schreiber, Daniel K.; Olszta, Matthew J.; Bruemmer, Stephen M.

    2014-10-01

    High-resolution microscopy of a high-purity Ni-5Cr alloy exposed to 360°C hydrogenated water reveals intergranular selective oxidation of Cr accompanied by local Cr depletion and diffusion-induced grain boundary migration (DIGM). The corrosion-product oxide consists of a porous, interconnected network of Cr2O3 platelets with no further O ingress into the metal ahead. Extensive grain boundary depletion of Cr (to <0.05at.%) is observed typically 20–100 nm wide as a result of DIGM and reaching depths of many micrometers beyond the oxidation front.

  12. Investigation of fertility and in utero effects in rats chronically exposed to a high-intensity 60-Hz electric field

    SciTech Connect

    Seto, Y.J.; Majeau-Chargois, D.; Lymangrover, J.R.; Dunlap, W.P.; Walker, C.F.

    1984-11-01

    A study was undertaken to investigate subtle bioeffects in Sprague-Dawley rats chronically exposed to a 60-Hz electric field at 80 kV/m unperturbed intensity. The details of our exposure facility, artifact considerations, environmental conditions, and exposure protocol are reported in this paper. Results of electric field exposure on reproduction and prenatal and postnatal development of rats over four generations are discussed. Statistical analysis of data from 305 females, 213 pregnancies, and 2683 births revealed no effects of electric field exposure on fertility, fecundity, nurturing, survival, or sex ratio of off-spring. In the final generation, 51 pregnant females were euthanized between days 16 and 20 of gestation, and 681 fetuses were carefully examined for gross malformations. Statistical analysis indicated that exposure to the electric field produced no significant increase in gross malformations, nor were any differences noted in resorptions, orientation of fetus in utero, sex ratio, or differential frequencies of uterine horn implantation. A detailed discussion of statistical power and sensitivity is included.

  13. Window contamination on Expose-R

    NASA Astrophysics Data System (ADS)

    Demets, R.; Bertrand, M.; Bolkhovitinov, A.; Bryson, K.; Colas, C.; Cottin, H.; Dettmann, J.; Ehrenfreund, P.; Elsaesser, A.; Jaramillo, E.; Lebert, M.; van Papendrecht, G.; Pereira, C.; Rohr, T.; Saiagh, K.

    2015-01-01

    Expose is a multi-user instrument for astrobiological and astrochemical experiments in space. Installed at the outer surface of the International Space Station, it enables investigators to study the impact of the open space environment on biological and biochemical test samples. Two Expose missions have been completed so far, designated as Expose-E (Rabbow et al. 2012) and Expose-R (Rabbow et al. this issue). One of the space-unique environmental factors offered by Expose is full-spectrum, ultraviolet (UV)-rich electromagnetic radiation from the Sun. This paper describes and analyses how on Expose-R, access of the test samples to Solar radiation degraded during space exposure in an unpredicted way. Several windows in front of the Sun-exposed test samples acquired a brown shade, resulting in a reduced transparency in visible light, UV and vacuum UV (VUV). Post-flight investigations revealed the discolouration to be caused by a homogenous film of cross-linked organic polymers at the inside of the windows. The chemical signature varied per sample carrier. No such films were found on windows from sealed, pressurized compartments, or on windows that had been kept out of the Sun. This suggests that volatile compounds originating from the interior of the Expose facility were cross-linked and photo-fixed by Solar irradiation at the rear side of the windows. The origin of the volatiles was not fully identified; most probably there was a variety of sources involved including the biological test samples, adhesives, plastics and printed circuit boards. The outer surface of the windows (pointing into space) was chemically impacted as well, with a probable effect on the transparency in VUV. The reported analysis of the window contamination on Expose-R is expected to help the interpretation of the scientific results and offers possibilities to mitigate this problem on future missions - in particular Expose-R2, the direct successor of Expose-R.

  14. Directly correlated transmission electron microscopy and atom probe tomography of grain boundary oxidation in a Ni-Al binary alloy exposed to high-temperature water

    SciTech Connect

    Schreiber, Daniel K.; Olszta, Matthew J.; Bruemmer, Stephen M.

    2013-06-14

    Intergranular oxidation of a Ni-4Al alloy exposed to hydrogenated, high-temperature water was characterized using directly correlated transmission electron microscopy and atom probe tomography. These combined analyses revealed that discrete, well-separated oxides (NiAl2O4) precipitated along grain boundaries in the metal. Aluminum was depleted from the grain boundary between oxides and also from one side of the boundary as a result of grain boundary migration. The discrete oxide morphology, disconnected from the continuous surface oxidation, suggests intergranular solid-state internal oxidation of Al. Keywords: oxidation; grain boundaries; nickel alloys; atom probe tomography; transmission electron microscopy (TEM)

  15. High-Resolution Crystal Structures Elucidate the Molecular Basis of Cholera Blood Group Dependence.

    PubMed

    Heggelund, Julie Elisabeth; Burschowsky, Daniel; Bjørnestad, Victoria Ariel; Hodnik, Vesna; Anderluh, Gregor; Krengel, Ute

    2016-04-01

    Cholera is the prime example of blood-group-dependent diseases, with individuals of blood group O experiencing the most severe symptoms. The cholera toxin is the main suspect to cause this relationship. We report the high-resolution crystal structures (1.1-1.6 Å) of the native cholera toxin B-pentamer for both classical and El Tor biotypes, in complexes with relevant blood group determinants and a fragment of its primary receptor, the GM1 ganglioside. The blood group A determinant binds in the opposite orientation compared to previously published structures of the cholera toxin, whereas the blood group H determinant, characteristic of blood group O, binds in both orientations. H-determinants bind with higher affinity than A-determinants, as shown by surface plasmon resonance. Together, these findings suggest why blood group O is a risk factor for severe cholera.

  16. High-Resolution Crystal Structures Elucidate the Molecular Basis of Cholera Blood Group Dependence

    PubMed Central

    Heggelund, Julie Elisabeth; Burschowsky, Daniel; Bjørnestad, Victoria Ariel; Hodnik, Vesna; Anderluh, Gregor; Krengel, Ute

    2016-01-01

    Cholera is the prime example of blood-group-dependent diseases, with individuals of blood group O experiencing the most severe symptoms. The cholera toxin is the main suspect to cause this relationship. We report the high-resolution crystal structures (1.1–1.6 Å) of the native cholera toxin B-pentamer for both classical and El Tor biotypes, in complexes with relevant blood group determinants and a fragment of its primary receptor, the GM1 ganglioside. The blood group A determinant binds in the opposite orientation compared to previously published structures of the cholera toxin, whereas the blood group H determinant, characteristic of blood group O, binds in both orientations. H-determinants bind with higher affinity than A-determinants, as shown by surface plasmon resonance. Together, these findings suggest why blood group O is a risk factor for severe cholera. PMID:27082955

  17. Groups with Historically High Incidences of Unemployment. A Report to the Congress.

    ERIC Educational Resources Information Center

    Helmeke, Kerry; And Others

    This report dealing with groups with historically high incidences of unemployment is made in response to Section 4 (d) (3) of the Fair Labor Standards Act. (These groups include teenagers; 20-24 year-olds; veterans [20-24 year-olds]; females; blacks and other minorities; persons of Hispanic origin; and the elderly [65 years and older]). The report…

  18. Flexible Grouping and Student Learning in a High-Needs School

    ERIC Educational Resources Information Center

    Castle, Sharon; Deniz, Carla Baker; Tortora, Michael

    2005-01-01

    The study focused on the impact of flexible grouping on student learning during a period of time in a high-needs school. The study tracked non transient, below-goal elementary students on multiple literacy assessments during a 5-year flexible grouping implementation. Results showed that the percentage of students attaining mastery increased in 16…

  19. 77 FR 1778 - U.S.-EU High Level Working Group on Jobs and Growth

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-11

    ... TRADE REPRESENTATIVE U.S.-EU High Level Working Group on Jobs and Growth AGENCY: Office of the United... Working Group on Jobs and Growth, led by U.S. Trade Representative Ron Kirk and EU Trade Commissioner... and investment to support mutually beneficial job creation, economic growth, and...

  20. Preference for High Status Predicts Implicit Outgroup Bias among Children from Low-Status Groups

    ERIC Educational Resources Information Center

    Newheiser, Anna-Kaisa; Dunham, Yarrow; Merrill, Anna; Hoosain, Leah; Olson, Kristina R.

    2014-01-01

    Whereas members of high-status racial groups show ingroup preference when attitudes are measured implicitly, members of low-status racial groups--both adults and children--typically show no bias, potentially reflecting awareness of the ingroup's low status. We hypothesized that when status differences are especially pronounced, children from…

  1. Teratogenicity, genotoxicity and oxidative stress in zebrafish embryos (Danio rerio) co-exposed to arsenic and atrazine.

    PubMed

    Adeyemi, Joseph A; da Cunha Martins-Junior, Airton; Barbosa, Fernando

    2015-01-01

    Arsenic and atrazine are common environmental contaminants probably due to their extensive use as pesticides on agricultural farmlands. In this study, zebrafish embryos were exposed to 0.8mM arsenic, 0.1mM atrazine or mixture of both for 96h, and various indices which are indicative of teratogenicity (egg coagulation, growth retardation, edema formation, hatching success, scoliosis), genotoxicity (DNA tail moments) and oxidative stress (lipid peroxidation and reduced glutathione (GSH) levels, catalase and glutathione peroxidase activities) were determined. The negative control were exposed to 0.5% DMSO while the positive control group were exposed to 4mg/L 3,4 dichloroaniline. Egg coagulation was highest in the positive control (85%), followed by the group that was exposed to mixture of arsenic and atrazine (30%) and least in the arsenic-exposed group (20%). The incidences of edema (59%) and growth retardation (35.2%) were more frequent in the group that was exposed to contaminant mixture and least in atrazine-exposed group where incidences of both edema and growth retardation were 15%. The incidence of scoliosis ranged between 20% in arsenic-exposed group and 10% in atrazine-exposed group. Hatching success was generally high in all the groups ranging between 95% in atrazine-exposed group and 88% in the group that was exposed to mixture of arsenic and atrazine. There was no evidence of teratogenic effect in the negative control group. DNA tail moments and lipid peroxidation levels increased significantly while GSH levels and catalase activity decreased significantly in contaminant-exposed groups, especially the mixture compared to the negative control. There was no significant change in GPx activity in the exposed groups compared to the negative control. The results of this study demonstrate that both arsenic and atrazine are potentially teratogenic and genotoxic, and can cause oxidative stress in zebrafish embryos, and these effects are potentiated by toxic

  2. Teratogenicity, genotoxicity and oxidative stress in zebrafish embryos (Danio rerio) co-exposed to arsenic and atrazine.

    PubMed

    Adeyemi, Joseph A; da Cunha Martins-Junior, Airton; Barbosa, Fernando

    2015-01-01

    Arsenic and atrazine are common environmental contaminants probably due to their extensive use as pesticides on agricultural farmlands. In this study, zebrafish embryos were exposed to 0.8mM arsenic, 0.1mM atrazine or mixture of both for 96h, and various indices which are indicative of teratogenicity (egg coagulation, growth retardation, edema formation, hatching success, scoliosis), genotoxicity (DNA tail moments) and oxidative stress (lipid peroxidation and reduced glutathione (GSH) levels, catalase and glutathione peroxidase activities) were determined. The negative control were exposed to 0.5% DMSO while the positive control group were exposed to 4mg/L 3,4 dichloroaniline. Egg coagulation was highest in the positive control (85%), followed by the group that was exposed to mixture of arsenic and atrazine (30%) and least in the arsenic-exposed group (20%). The incidences of edema (59%) and growth retardation (35.2%) were more frequent in the group that was exposed to contaminant mixture and least in atrazine-exposed group where incidences of both edema and growth retardation were 15%. The incidence of scoliosis ranged between 20% in arsenic-exposed group and 10% in atrazine-exposed group. Hatching success was generally high in all the groups ranging between 95% in atrazine-exposed group and 88% in the group that was exposed to mixture of arsenic and atrazine. There was no evidence of teratogenic effect in the negative control group. DNA tail moments and lipid peroxidation levels increased significantly while GSH levels and catalase activity decreased significantly in contaminant-exposed groups, especially the mixture compared to the negative control. There was no significant change in GPx activity in the exposed groups compared to the negative control. The results of this study demonstrate that both arsenic and atrazine are potentially teratogenic and genotoxic, and can cause oxidative stress in zebrafish embryos, and these effects are potentiated by toxic

  3. Hierarchical sulfur-impregnated hydrogenated TiO2 mesoporous spheres comprising anatase nanosheets with highly exposed (001) facets for advanced Li-S batteries

    NASA Astrophysics Data System (ADS)

    Yuan, Changzhou; Zhu, Siqi; Cao, Hui; Hou, Linrui; Lin, Jingdong

    2016-01-01

    In this contribution, we purposefully designed hierarchical hydrogenated TiO2 spheres (HTSs) constructed from ultrathin anatase nanosheets with highly exposed (001) facets, and further utilized them as an efficient encapsulated host of sulfur species for advanced Li-S batteries (LSBs). Strikingly, the as-fabricated hybrid S/HTSs cathode exhibited high Coulombic efficiency (>94%), exceptional long cycling performance (capacity decay of ˜0.399% per cycle at 0.5 C), and large reversible discharge capacity (˜579 mAh g-1 at 2.0 C) at high C rates, benefiting from better electronic conductivity, smaller charge transfer resistance and strong chemical bonding between {{{{S}}}n}2- and the reduced (001) facets of HTSs, according to experimental measurements and systematical theoretical calculations. More significantly, our in-depth insights into the mechanism involved in the hybrid S/HTSs could efficiently guide future design, optimization and synthesis of other metal oxide-based matrixes with specific exposed crystal facets for next-generation advanced LSBs.

  4. High Frequency and Regular Audiometry among Selected Groups of High School Students

    ERIC Educational Resources Information Center

    Corliss, Leland M.; And Others

    1970-01-01

    Among study findings are: (1) girls seem to have less tendency to acoustic trauma than boys though the sampling groups was smaller; (2) the significant difference exists between those students who subject their ears to loud noises regularly and those who do not. (Author)

  5. High-resolution nuclear microprobe elemental mapping of teeth enamel-dentine interface exposed to acidic conditions

    NASA Astrophysics Data System (ADS)

    Pineda-Vargas, C. A.; Eisa, M. E.; Chikte, U. M. E.; Conradie, J. L.

    2004-10-01

    The process of demineralisation in tooth erosion due to exposure to acidic media was investigated in a group of test and control healthy human molar teeth. Analysis by micro-PIXE and proton-backscattering showed that the levels of trace elements were enriched and/or depleted according to experimental treatment. The atomic ratios of major constituents in the matrix were characteristic of test or controls with typical ratios: O 5P 1Ca 3F 1 for tests and O 6P 0.5Ca 3F 0.5 for controls. The correlation between maps of Ca and Zn in and around the interface between dentine and enamel in control samples showed two kinds of correlation strengths (for enamel and dentine). The strongest correlation was related to the enamel area.

  6. Analysis of unrejoined chromosomal breakage in human fibroblast cells exposed to low- and high-LET radiation

    NASA Technical Reports Server (NTRS)

    Wu, Honglu; Furusawa, Yoshiya; George, Kerry; Kawata, Tetsuya; Cucinotta, Francis A.

    2002-01-01

    Reported studies of DNA breakage induced by radiation of various qualities have generally shown a higher fraction of unrejoined residual breaks after high-LET exposure. This observation is supported by the argument that high-LET radiation induced DNA breaks that are more complex in nature and, thus, less likely to be repaired. In most cases the doses used in these studies were very high. We have studied unrejoined chromosome breaks by analyzing chromosome aberrations using a fluorescence in situ hybridization (FISH) technique with a combination of whole chromosome specific probes and probes specific for the telomere region of the chromosomes. Confluent human fibroblast cells (AG1522) were irradiated with gamma rays, 490 MeV/nucleon Si, or with Fe ions at either 200 and 500 MeV/nucleon, and were allowed to repair at 37 degrees C for 24 hours after exposure. A chemically induced premature chromosome condensation (PCC) technique was used to condense chromosomes in the G2 phase of the cell cycle. Results showed that the frequency of unrejoined chromosome breaks was higher after high-LET radiation, and the ratio of unrejoined to misrejoined chromosome breaks increased steadily with LET up a peak value at 440 keV/microm.

  7. Asymmetric anatase TiO2 nanocrystals with exposed high-index facets and their excellent lithium storage properties

    NASA Astrophysics Data System (ADS)

    Wu, Hao Bin; Chen, Jun Song; Lou, Xiong Wen (David); Hng, Huey Hoon

    2011-10-01

    In this work, we demonstrate a unique organic solvent system to synthesize asymmetric anatase TiO2 nanocrystals with a bipyramidal structure, where the upper pyramid is bound by (201) facets, and the lower pyramid is bound by (401) surfaces. Due to the high surface energy of these (401) high-index facets, the nanocrystals tend to assemble on these facets to minimize the free energy, leading to the formation of a dandelion-like hierarchical structure.In this work, we demonstrate a unique organic solvent system to synthesize asymmetric anatase TiO2 nanocrystals with a bipyramidal structure, where the upper pyramid is bound by (201) facets, and the lower pyramid is bound by (401) surfaces. Due to the high surface energy of these (401) high-index facets, the nanocrystals tend to assemble on these facets to minimize the free energy, leading to the formation of a dandelion-like hierarchical structure. Electronic supplementary information (ESI) available: Detailed experimental procedures, supplementary BET/SEM/TEM/XRD/electrochemical data. See DOI: 10.1039/c1nr10854a

  8. NEUROBEHAVIORAL EVALUATION OF RATS EXPOSED TO CHLORPYRIFOS VIA CHRONIC DIETARY AND REPEATED HIGH-LEVEL SPIKE EXPOSURE.

    EPA Science Inventory

    This study aimed to model long-term subtoxic human exposure to an organophosphorus pesticide, chlorpyrifos (CPF), and to examine the influence of that exposure on the response to intermittent high-dose acute challenges. Adult Long-Evans male rats were maintained at 350g body wei...

  9. Imbalance between oxygen photoreduction and antioxidant capacities in Symbiodinium cells exposed to combined heat and high light stress

    NASA Astrophysics Data System (ADS)

    Roberty, S.; Fransolet, D.; Cardol, P.; Plumier, J.-C.; Franck, F.

    2015-12-01

    During the last decades, coral reefs have been affected by several large-scale bleaching events, and such phenomena are expected to increase in frequency and severity in the future, thus compromising their survival. High sea surface temperature accompanied by high levels of solar irradiance has been found to be responsible for the induction of oxidative stress ultimately ending with the disruption of the symbiosis between cnidarians and Symbiodinium. For two decades, many studies have pointed to the water-water cycle (WWC) as being one of the primary mediators of this phenomenon, but the impacts of environmental stress on the O2 reduction by PSI and the associated reactive oxygen species (ROS)-detoxifying enzymes remain to be determined. In this study, we analyzed the impacts of acute thermal and light stress on the WWC in the model Symbiodinium strain A1. We observed that the high light treatment at 26 °C resulted in the up-regulation of superoxide dismutase, ascorbate peroxidase, and glutathione reductase activities and an increased production of ROS with no significant change in O2-dependent electron transport. Under high light and at 33 °C, O2-dependent electron transport was significantly increased relative to total electron transport. This increase was concomitant with a twofold increase in ROS generation compared with the treatment at 26 °C, while enzymes involved in the WWC were largely inactivated. These data show for the first time that combined heat and light stress inactivate antioxidant capacities of the WWC and suggests that its photoprotective functions are overwhelmed under these conditions. This study also indicates that cnidarians may be more prone to bleach if they harbor Symbiodinium cells having a highly active Mehler-type electron transport, unless they are able to quickly up-regulate their antioxidant capacities.

  10. A Secure Multicast Framework in Large and High-Mobility Network Groups

    NASA Astrophysics Data System (ADS)

    Lee, Jung-San; Chang, Chin-Chen

    With the widespread use of Internet applications such as Teleconference, Pay-TV, Collaborate tasks, and Message services, how to construct and distribute the group session key to all group members securely is becoming and more important. Instead of adopting the point-to-point packet delivery, these emerging applications are based upon the mechanism of multicast communication, which allows the group member to communicate with multi-party efficiently. There are two main issues in the mechanism of multicast communication: Key Distribution and Scalability. The first issue is how to distribute the group session key to all group members securely. The second one is how to maintain the high performance in large network groups. Group members in conventional multicast systems have to keep numerous secret keys in databases, which makes it very inconvenient for them. Furthermore, in case that a member joins or leaves the communication group, many involved participants have to change their own secret keys to preserve the forward secrecy and the backward secrecy. We consequently propose a novel version for providing secure multicast communication in large network groups. Our proposed framework not only preserves the forward secrecy and the backward secrecy but also possesses better performance than existing alternatives. Specifically, simulation results demonstrate that our scheme is suitable for high-mobility environments.

  11. Evaluation of the EGSnrc Monte Carlo code for interface dosimetry near high-Z media exposed to kilovolt and 60Co photons

    NASA Astrophysics Data System (ADS)

    Verhaegen, Frank

    2002-05-01

    High atomic number (Z) heterogeneities in tissue exposed to photons with energies of up to about 1 MeV can cause significant dose perturbations in their immediate vicinity. The recently released Monte Carlo (MC) code EGSnrc (Kawrakow 2000a Med. Phys. 27 485-98) was used to investigate the dose perturbation of high-Z heterogeneities in tissue in kilovolt (kV) and 60Co photon beams. Simulations were performed of measurements with a dedicated thin-window parallel-plate ion chamber near a high-Z interface in a 60Co photon beam (Nilsson et al 1992 Med. Phys. 19 1413-21). Good agreement was obtained between simulations and measurements for a detailed set of experiments in which the thickness of the ion chamber window, the thickness of the air gap between ion chamber and heterogeneity, the depth of the ion chamber in polystyrene and the material of the interface was varied. The EGSnrc code offers several improvements in the electron and photon production and transport algorithms over the older EGS4/PRESTA code (Nelson et al 1985 Stanford Linear Accelerator Center Report SL AC-265, Bielajew and Rogers 1987 Nucl. Instrum. Methods Phys. Res. B 18 165-81). The influence of the new EGSnrc features was investigated for simulations of a planar slab of a high-Z medium embedded in water and exposed to kV or 60Co photons. It was found that using the new electron transport algorithm in EGSnrc, including relativistic spin effects in elastic scattering, significantly affects the calculation of dose distribution near high-Z interfaces. The simulations were found to be independent of the maximum fractional electron energy loss per step (ESTEPE), which was often a cause for concern in older EGS4 simulations. Concerning the new features of the photon transport algorithm sampling of the photoelectron angular distribution was found to have a significant effect, whereas the effect of binding energies in Compton scatter was found to be negligible. A slight dose artefact very close to high

  12. Coarsening behaviour of M23C6 carbides in creep-resistant steel exposed to high temperatures

    NASA Astrophysics Data System (ADS)

    Godec, M.; Skobir Balantič, D. A.

    2016-07-01

    High operating temperatures can have very deleterious effects on the long-term performance of high-Cr, creep-resistant steels used, for example, in the structural components of power plants. For the popular creep-resistant steel X20CrMoV12.1 we analysed the processes of carbide growth using a variety of analytical techniques: transmission electron microscopy (TEM) and diffraction (TED), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD). The evolution of the microstructure after different aging times was the basis for a much better understanding of the boundary-migration processes and the growth of the carbides. We present an explanation as to why some locations are preferential for this growth, and using EBSD we were able to define the proper orientational relationship between the carbides and the matrix.

  13. Coarsening behaviour of M23C6 carbides in creep-resistant steel exposed to high temperatures.

    PubMed

    Godec, M; Skobir Balantič, D A

    2016-01-01

    High operating temperatures can have very deleterious effects on the long-term performance of high-Cr, creep-resistant steels used, for example, in the structural components of power plants. For the popular creep-resistant steel X20CrMoV12.1 we analysed the processes of carbide growth using a variety of analytical techniques: transmission electron microscopy (TEM) and diffraction (TED), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD). The evolution of the microstructure after different aging times was the basis for a much better understanding of the boundary-migration processes and the growth of the carbides. We present an explanation as to why some locations are preferential for this growth, and using EBSD we were able to define the proper orientational relationship between the carbides and the matrix. PMID:27406340

  14. Coarsening behaviour of M23C6 carbides in creep-resistant steel exposed to high temperatures

    PubMed Central

    Godec, M.; Skobir Balantič, D. A.

    2016-01-01

    High operating temperatures can have very deleterious effects on the long-term performance of high-Cr, creep-resistant steels used, for example, in the structural components of power plants. For the popular creep-resistant steel X20CrMoV12.1 we analysed the processes of carbide growth using a variety of analytical techniques: transmission electron microscopy (TEM) and diffraction (TED), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD). The evolution of the microstructure after different aging times was the basis for a much better understanding of the boundary-migration processes and the growth of the carbides. We present an explanation as to why some locations are preferential for this growth, and using EBSD we were able to define the proper orientational relationship between the carbides and the matrix. PMID:27406340

  15. [Change in the properties of titanium alloys exposed to a stream of high-frequency, low-pressure radiating plasma].

    PubMed

    Matukhnov, V M; Abdullin, I Sh; Altareva, G I; Zheltukhin, V S; Gerasev, G P

    1985-01-01

    The Nitrogen-Argon plasma of a high-frequency low-pressure discharge is proven to be very effective in machining pieces made of titanium alloys. The optimum operating modes are found that improve surface microhardness, reduce surface roughness, increase durability and endurance limits, and do not produce the effect on the residual stress. The operating modes have been tested with great success in machining microsurgical and ultrasonic surgical instruments.

  16. Possibility of the effect of absolute negative conductivity in quantum superlattice exposed to the high-frequency electromagnetic radiation

    NASA Astrophysics Data System (ADS)

    Kryuchkov, S. V.; Kukhar', E. I.

    2015-07-01

    Current density in superlattice placed in quantizing electric field and in high-frequency field of electromagnetic wave was calculated. The calculations were performed by taking into account an inelastic scattering of charge carriers by phonons. Possibility of the effect of absolute negative conductivity, i.e. the effect of appearance of electric current flowing in opposite direction than that of vector of quantizing electric field intensity, was shown. Such effect in graphene superlattices was discussed.

  17. High self-control protects the link between social support and positivity ratio for Israeli students exposed to contextual risk.

    PubMed

    Orkibi, Hod; Ronen, Tammie

    2015-08-01

    This study examined how Israeli students, despite exposure to contextual risk factors, may experience a high ratio of self-reported positive to negative emotions (i.e., positivity ratio). Self-control skills and perceived social support were tested as protective factors, where each was posited to moderate the relation between risk status and positivity ratio. The participants were 460 Israeli students (51% girls) in grades 8-10. Contrary to expectations, students attending a school with high contextual risks did not differ from students attending a school with low contextual risks in their scores on self-control skills, perceived social support, or positivity ratio. However, an exploratory follow-up moderation analysis revealed a significant three-way interaction, indicating that while low self-control skills eliminate the link between social support and positivity ratio for students attending the school defined as at-risk, high self-control protects this link. These results suggest that neither contextual risk in itself nor initial differences in self-control or social support account for differences in students' positivity ratio. Rather, it is the way these factors interact with each other that matters. Study limitations and implications are discussed.

  18. Pathogenesis of tuberculosis in mice exposed to low and high doses of an environmental mycobacterial saprophyte before infection.

    PubMed Central

    Hernandez-Pando, R; Pavön, L; Arriaga, K; Orozco, H; Madrid-Marina, V; Rook, G

    1997-01-01

    Mycobacteria are ubiquitous in the environment, but they are not part of the normal human microbial flora. It has been suggested that variable contact with mycobacteria can influence susceptibility to mycobacterial pathogens and the efficacy of subsequent Mycobacterium bovis BCG vaccination. To test this, mice were immunized with high or low doses of an environmental saprophyte, M. vaccae, that is intensely immunogenic as an autoclaved preparation. Two months later, they received an intratracheal challenge with M. tuberculosis H37Rv. Recipients of a low Th1-inducing dose (10(7) organisms) were partially protected and maintained a high ratio of interleukin 2 (IL-2)-positive to IL-4-positive cells in the perivascular, peribronchial, and granulomatous areas of the lung, whereas in unimmunized controls the IL-4-positive cells increased markedly between days 21 and 28. In contrast, recipients of the high dose (10(9) organisms), which primes Th2 as well as Th1 cytokine production, died more rapidly than unimmunized controls and showed massive pneumonia from day 7. The ratio of IL-2-positive to IL-4-positive cells in all compartments of the lung rapidly fell to 1 by day 14 for these animals. These events correlated with cytokine mRNA profiles and with increases in the local toxicity of tumor necrosis factor alpha (TNF-alpha), demonstrable only when a major Th2 component was present. These data indicate that cross-reactive epitopes present in an environmental saprophyte can evoke either protective responses or responses that increase susceptibility to M. tuberculosis. The latter are associated with the presence of a Th2 component and increased sensitivity to TNF-alpha. PMID:9234793

  19. Restoring redox balance enhances contractility in heart trabeculae from type 2 diabetic rats exposed to high glucose

    PubMed Central

    Bhatt, Niraj M.; Aon, Miguel A.; Tocchetti, Carlo G.; Shen, Xiaoxu; Dey, Swati; Ramirez-Correa, Genaro; O′Rourke, Brian; Gao, Wei Dong

    2014-01-01

    Hearts from type 2 diabetic (T2DM) subjects are chronically subjected to hyperglycemia and hyperlipidemia, both thought to contribute to oxidizing conditions and contractile dysfunction. How redox alterations and contractility interrelate, ultimately diminishing T2DM heart function, remains poorly understood. Herein we tested whether the fatty acid palmitate (Palm), in addition to its energetic contribution, rescues function by improving redox [glutathione (GSH), NAD(P)H, less oxidative stress] in T2DM rat heart trabeculae subjected to high glucose. Using cardiac trabeculae from Zucker Diabetic Fatty (ZDF) rats, we assessed the impact of low glucose (EG) and high glucose (HG), in absence or presence of Palm or insulin, on force development, energetics, and redox responses. We found that in EG ZDF and lean trabeculae displayed similar contractile work, yield of contractile work (Ycw), representing the ratio of force time integral over rate of O2 consumption. Conversely, HG had a negative impact on Ycw, whereas Palm, but not insulin, completely prevented contractile loss. This effect was associated with higher GSH, less oxidative stress, and augmented matrix GSH/thioredoxin (Trx) in ZDF mitochondria. Restoration of myocardial redox with GSH ethyl ester also rescued ZDF contractile function in HG, independently from Palm. These results support the idea that maintained redox balance, via increased GSH and Trx antioxidant activities to resist oxidative stress, is an essential protective response of the diabetic heart to keep contractile function. PMID:25485897

  20. Kinetics of chromatid break repair in G2-human fibroblasts exposed to low- and high-LET radiations

    NASA Technical Reports Server (NTRS)

    Kawata, T.; Durante, M.; George, K.; Furusawa, Y.; Gotoh, E.; Takai, N.; Wu, H.; Cucinotta, F. A.

    2001-01-01

    The purpose of this study is to determine the kinetics of chromatid break rejoining following exposure to radiations of different quality. Exponentially growing human fibroblast cells AG1522 were irradiated with gamma-rays, energetic carbon (290 MeV/u), silicon (490 MeV/u) and iron (200 MeV/u, 600 MeV/u). Chromosomes were prematurely condensed using calyculin A. Prematurely condensed chromosomes were collected after several post-irradiation incubation times, ranging from 5 to 600 minutes, and the number of chromatid breaks and exchanges in G2 cells were scored. The relative biological effectiveness (RBE) for initial chromatid breaks per unit dose showed LET dependency having a peak at 55 keV/micrometers silicon (2.4) or 80 keV/micrometers carbon particles (2.4) and then decreased with increasing LET. The kinetics of chromatid break rejoining following low- or high-LET irradiation consisted of two exponential components. Chromatid breaks decreased rapidly after exposure, and then continued to decrease at a slower rate. The rejoining kinetics was similar for exposure to each type of radiation, although the rate of unrejoined breaks was higher for high-LET radiation. Chromatid exchanges were also formed quickly.

  1. A High-Leverage Language Teaching Practice: Leading an Open-Ended Group Discussion

    ERIC Educational Resources Information Center

    Kearney, Erin

    2015-01-01

    In response to calls for more practice-based teacher education, this study investigated the way in which two high-performing novice world language teachers, one in Spanish and one in Latin, implemented a high-leverage teaching practice, leading an open-ended group discussion. Observational data revealed a number of constituent micro-practices. The…

  2. Sense of Belonging among High School Students Representing 4 Ethnic Groups

    ERIC Educational Resources Information Center

    Faircloth, Beverly S.; Hamm, Jill V.

    2005-01-01

    The authors investigated the dimensions and mechanisms of belonging relevant to motivation and achievement among high school students representing 4 ethnic groups. Using survey data from 9th to 12th grade students (N = 5,494) attending 7 ethnically-diverse high schools, structural equation modeling was employed to explore, independently for each…

  3. Effects of film thickness on scintillation characteristics of columnar CsI:Tl films exposed to high gamma radiation doses

    NASA Astrophysics Data System (ADS)

    Shinde, Seema; Singh, S. G.; Sen, S.; Gadkari, S. C.

    2016-02-01

    Oriented columnar films of Tl doped CsI (CsI:Tl) of varying thicknesses from 50 μm to 1000 μm have been deposited on silica glass substrates by a thermal evaporation technique. The SEM micrographs confirmed the columnar structure of the film while the powder X-ray diffraction pattern recorded for the films revealed a preferred orientation of the grown columns along the <200> direction. Effects of high energy gamma exposure up to 1000 Gy on luminescence properties of the films were investigated. Results of radio-luminescence, photo-luminescence and scintillation studies on the films are compared with those of a CsI:Tl single crystal with similar thickness. A possible correlation between the film thicknesses and radiation damage in films has been observed.

  4. Characterization of microstructure and property evolution in advanced cladding and duct: Materials exposed to high dose and elevated temperature

    DOE PAGES

    Allen, Todd R.; Kaoumi, Djamel; Wharry, Janelle P.; Jiao, Zhijie; Topbasi, Cem; Kohnert, Aaron; Barnard, Leland; Certain, Alicia; Field, Kevin G.; Was, Gary S.; et al

    2015-05-20

    Designing materials for performance in high-radiation fields can be accelerated through a carefully chosen combination of advanced multiscale modeling paired with appropriate experimental validation. Here, the studies reported in this work, the combined efforts of six universities working together as the Consortium on Cladding and Structural Materials, use that approach to focus on improving the scientific basis for the response of ferritic–martensitic steels to irradiation. A combination of modern modeling techniques with controlled experimentation has specifically focused on improving the understanding of radiation-induced segregation, precipitate formation and growth under radiation, the stability of oxide nanoclusters, and the development of dislocationmore » networks under radiation. Experimental studies use both model and commercial alloys, irradiated with both ion beams and neutrons. Lastly, transmission electron microscopy and atom probe are combined with both first-principles and rate theory approaches to advance the understanding of ferritic–martensitic steels.« less

  5. Characterization of microstructure and property evolution in advanced cladding and duct: Materials exposed to high dose and elevated temperature

    SciTech Connect

    Allen, Todd R.; Kaoumi, Djamel; Wharry, Janelle P.; Jiao, Zhijie; Topbasi, Cem; Kohnert, Aaron; Barnard, Leland; Certain, Alicia; Field, Kevin G.; Was, Gary S.; Morgan, Dane L.; Motta, Arthur T.; Wirth, Brian D.; Yang, Y.

    2015-05-20

    Designing materials for performance in high-radiation fields can be accelerated through a carefully chosen combination of advanced multiscale modeling paired with appropriate experimental validation. Here, the studies reported in this work, the combined efforts of six universities working together as the Consortium on Cladding and Structural Materials, use that approach to focus on improving the scientific basis for the response of ferritic–martensitic steels to irradiation. A combination of modern modeling techniques with controlled experimentation has specifically focused on improving the understanding of radiation-induced segregation, precipitate formation and growth under radiation, the stability of oxide nanoclusters, and the development of dislocation networks under radiation. Experimental studies use both model and commercial alloys, irradiated with both ion beams and neutrons. Lastly, transmission electron microscopy and atom probe are combined with both first-principles and rate theory approaches to advance the understanding of ferritic–martensitic steels.

  6. Serosurvey of prevalence of human immunodeficiency virus amongst high risk groups in Port Sudan, Sudan.

    PubMed

    Burans, J P; McCarthy, M; el Tayeb, S M; el Tigani, A; George, J; Abu-Elyazeed, R; Woody, J N

    1990-09-01

    During October, 1987, 593 sera were collected from risk groups in Sudan's only major deepwater port, Port Sudan. The risk groups included prostitutes, lorry drivers and prisoners. A large proportion of the study participants practised high risk behaviour which included sexual promiscuity, medical treatment by injection, scarification and tattooing. Despite high risk behaviour and evidence of a high prevalence of hepatitis B infection, a virus transmitted in a manner similar to HIV, no study participants were positive for HIV infection. This data suggests that the prevalence of HIV infection amongst high risk groups in Port Sudan is very low. These findings confirm a lack of clinical cases of AIDS in hospitalized patients in Port Sudan and the small number of reported cases in other areas of northern Sudan. PMID:2253574

  7. REPORT OF THE SNOWMASS M6 WORKING GROUP ON HIGH INTENSITY PROTON SOURCES.

    SciTech Connect

    CHOU,W.; WEI,J.

    2001-08-14

    The M6 working group had more than 40 active participants (listed in Section 4). During the three weeks at Snowmass, there were about 50 presentations, covering a wide range of topics associated with high intensity proton sources. The talks are listed in Section 5. This group also had joint sessions with a number of other working groups, including E1 (Neutrino Factories and Muon Colliders), E5 (Fixed-Target Experiments), M1 (Muon Based Systems), T4 (Particle Sources), T5 (Beam dynamics), T7 (High Performance Computing) and T9 (Diagnostics). The M6 group performed a survey of the beam parameters of existing and proposed high intensity proton sources, in particular, of the proton drivers. The results are listed in Table 1. These parameters are compared with the requirements of high-energy physics users of secondary beams in Working Groups E1 and E5. According to the consensus reached in the E1 and E5 groups, the U.S. HEP program requires an intense proton source, a 1-4 MW Proton Driver, by the end of this decade.

  8. Re-187 Os-187 Isotopic and Highly Siderophile Element Systematics of Group IVB Irons

    NASA Technical Reports Server (NTRS)

    Honesto, J.; McDonough, W. F.; Walker, R. J.; McCoy, T. J.; Ash, R. D.

    2005-01-01

    Study of the magmatic iron meteorite groups permits constraints to be placed on the chemical and isotopic composition of parent bodies, and the timing of, and crystal-liquid fractionation processes involved in the crystallization of asteroidal cores. Here we examine Re-Os isotopic and trace elemental systematics of group IVB irons. Compared to most irons, the irons comprising this group are enriched in some of the most refractory siderophile elements, yet highly-depleted in most volatile siderophile elements. These characteristics have been attributed to processes such as high temperature condensation of precursor materials and oxidation in the parent body. Most recently it has been suggested that both processes may be involved in the chemical complexity of the group. Here, high precision isotopic and highly siderophile element (HSE) concentrations are used to further examine these possible origins, and the crystallization history of the group. In addition, we have begun to assess the possibility of relating certain ungrouped irons with major groups via multi-element, trace element modeling. In a companion abstract, the isotopic and trace element systematics of the ungrouped iron Tishomingo are compared with the IVB irons.

  9. Family correlations of arsenic methylation patterns in children and parents exposed to high concentrations of arsenic in drinking water.

    PubMed Central

    Chung, Joyce S; Kalman, David A; Moore, Lee E; Kosnett, Michael J; Arroyo, Alex P; Beeris, Martin; Mazumder, D N Guha; Hernandez, Alexandra L; Smith, Allan H

    2002-01-01

    We investigated the evidence of a familial contribution to urinary methylation patterns in families ingesting arsenic in drinking water. Arsenic methylation can be assessed by measuring urinary levels of inorganic arsenic (InAs) and its methylated metabolites, monomethylarsonate (MMA), and dimethylarsinate (DMA). Methylation activity is reflected in the ratios: InAs/methylated arsenic (InAs/metAs) and MMA/DMA. Eleven families from Chile were selected because of their long-term exposure to very high levels of arsenic in drinking water (735-762 microg/L). Each family consisted of a father, a mother, and two children. We measured urinary arsenic and its methylated metabolites for each participant (n = 44). The intraclass correlation coefficients showed that 13-52% of the variations in the methylation patterns were from being a member of a specific family. Family correlations were calculated for father-mother, parent-child, and sibling-sibling pairs. Methylation patterns correlated strongly between siblings [r = 0.78 for InAs/metAs, 95% confidence interval (CI), 0.34-0.94; r = 0.82 for MMA/DMA, 95%CI, 0.43-0.95] compared to lower correlations in father-mother pairs (r = 0.18, r = -0.01, respectively), after adjustment for total urinary arsenic, age, and sex. Family correlations were not notably altered when adjustments were made for specific blood micronutrients (methionine, homocysteine, folate, vitamin B6, selenium, and vitamin B12 potentially related to methylation. We also report on a family pedigree with high prevalence of arsenic-induced effects. Participants from this family had low InAs/metAs values, which is consistent with increased toxicity of trivalent methylated arsenic species. Despite our small sample size, we observed that methylation patterns aggregate in families and are correlated in siblings, providing evidence of a genetic basis for the variation in arsenic methylation. Larger studies with more extensive pedigrees will need to be conducted to

  10. Family correlations of arsenic methylation patterns in children and parents exposed to high concentrations of arsenic in drinking water.

    PubMed

    Chung, Joyce S; Kalman, David A; Moore, Lee E; Kosnett, Michael J; Arroyo, Alex P; Beeris, Martin; Mazumder, D N Guha; Hernandez, Alexandra L; Smith, Allan H

    2002-07-01

    We investigated the evidence of a familial contribution to urinary methylation patterns in families ingesting arsenic in drinking water. Arsenic methylation can be assessed by measuring urinary levels of inorganic arsenic (InAs) and its methylated metabolites, monomethylarsonate (MMA), and dimethylarsinate (DMA). Methylation activity is reflected in the ratios: InAs/methylated arsenic (InAs/metAs) and MMA/DMA. Eleven families from Chile were selected because of their long-term exposure to very high levels of arsenic in drinking water (735-762 microg/L). Each family consisted of a father, a mother, and two children. We measured urinary arsenic and its methylated metabolites for each participant (n = 44). The intraclass correlation coefficients showed that 13-52% of the variations in the methylation patterns were from being a member of a specific family. Family correlations were calculated for father-mother, parent-child, and sibling-sibling pairs. Methylation patterns correlated strongly between siblings [r = 0.78 for InAs/metAs, 95% confidence interval (CI), 0.34-0.94; r = 0.82 for MMA/DMA, 95%CI, 0.43-0.95] compared to lower correlations in father-mother pairs (r = 0.18, r = -0.01, respectively), after adjustment for total urinary arsenic, age, and sex. Family correlations were not notably altered when adjustments were made for specific blood micronutrients (methionine, homocysteine, folate, vitamin B6, selenium, and vitamin B12 potentially related to methylation. We also report on a family pedigree with high prevalence of arsenic-induced effects. Participants from this family had low InAs/metAs values, which is consistent with increased toxicity of trivalent methylated arsenic species. Despite our small sample size, we observed that methylation patterns aggregate in families and are correlated in siblings, providing evidence of a genetic basis for the variation in arsenic methylation. Larger studies with more extensive pedigrees will need to be conducted to

  11. High-resolution morphologic and spectral characteristics of Crater-exposed Bedrock on Mars: Insights into the petrogenesis, stratigraphy and geologic history of the Martian crust

    NASA Astrophysics Data System (ADS)

    Tornabene, L. L.; Caudill, C. M.; McEwen, A. S.; Osinski, G.; Wray, J. J.; Mustard, J. F.; Skok, J. R.; Marzo, G.; Grant, J. A.

    2010-12-01

    Rocks form under a variety of geologic settings and conditions, thus the mineral composition, texture, structures and stratigraphic relationships of exposed rocks provide geologists a means to access information about the past geologic and climatic history. Typically, tectonic events (e.g., orogenic) and erosional processes expose sections of older terrestrial rocks at the surface. On Mars, a lack of complex tectonics and lower erosion rates make these tectonic exposures virtually non-existent. Impacts, however, generate localized displacements and structural uplift of target rocks and exposes them within the crater rim, walls, terraces and central structural uplifts. Imagery from the High Resolution Imaging Science Experiment (HiRISE) of this Crater-Exposed Bedrock (CEB) reveals unprecedented meter to decameter textural and structural detail [1]. Our initial work, based on previous efforts [1-3], has revealed that not all craters are well exposed due to impact melt coatings and ongoing degradation, infilling, and mantling of crater rims, floors and walls. Thus, making a database (DB) of craters with good exposures is an essential step towards understanding the spatial and temporal distribution of CEB textures, structures and compositions. When complete, the DB will aid our ability to make inferences regarding the petrogenesis, evolution and geologic history of the upper crust at regional and potentially global scales. Our CEB DB will be used to focus on spectral units that specifically correlate with CEB textures and stratigraphic relationships. Our preliminary results suggest that CEB can be classified into three textural categories, 1) Megabreccias (MB), 2) Intact layered Stratigraphy (IS), and 3) a massive textured Fractured Bedrock (FB), with each of these classifications being informative with respect to a specific geologic setting or possible set of histories (e.g., late-heavy bombardment, cyclical volcanism and sedimentation). Preliminary spectral analyses

  12. Biosynthesis of lead nanoparticles by the aquatic water fern, Salvinia minima Baker, when exposed to high lead concentration.

    PubMed

    Castro-Longoria, E; Trejo-Guillén, K; Vilchis-Nestor, A R; Avalos-Borja, M; Andrade-Canto, S B; Leal-Alvarado, D A; Santamaría, J M

    2014-02-01

    Salvinia minima Baker is a small floating aquatic fern that is efficient for the removal and storage of heavy metals such as lead and cadmium. In this study, we report that lead removal by S. minima causes large accumulation of lead inside the cells in the form of nanoparticles (PbNPs). The accumulation pattern of lead was analyzed in both, submerged root-like modified fronds (here named "roots"), and in its aerial leaf-like fronds ("leaves"). Analysis by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) confirmed the biosynthesis of PbNPs by the plant. In both, roots and leaves, PbNPs were found to accumulate almost exclusively at the cell wall and closely associated to the cell membrane. Two types of PbNPs shapes were found in cells of both tissues, those associated to the cell wall were quasi-spherical with 17.2±4.2 nm of diameter, while those associated to the cell membrane/cytoplasm were elongated. Elongated particles were 53.7±29.6 nm in length and 11.1±2.4 nm wide. Infrared spectroscopy (IR) results indicate that cellulose, lignin and pectin are the major components that may be acting as the reducing agents for lead ions; these findings strongly suggest the potential use of this fern to further explore the bio-assisted synthesis of heavy metal nanostructures.

  13. Hydrogen embrittlement of cathodically protected high-strength, low-alloy steels exposed to sulfate-reducing bacteria

    SciTech Connect

    Robinson, M.J.; Kilgallon, P.J. . School of Industrial and Manufacturing Science)

    1994-08-01

    Hydrogen embrittlement (HE) of two high-strength, low-alloy steels was studied in conditions typical of the marine environment. Double-cantilever beam specimens, heat-treated to produce the microstructure in the heat-affected zone of a weld, were tested in seawater containing sulfate-reducing bacteria (SRB) at a range of cathodic protection potentials. The threshold stress intensities (K[sub th]) required to cause subcritical crack propagation were recorded. The concentration of H absorbed by the steel (C[sub 0]) was measured using a permeation technique and was shown to be higher at more cathodic potentials and significantly increased when SRB were present. An inverse relationship was established between log K[sub th] and C[sub 0] for sterile and biologically active environments. It was concluded that crack propagation occurred by a single HE mechanism, regardless of whether SRB were present. The bacteria were believed to increase sulfide concentration in the biofilm at the metal surface, which promoted increased C[sub 0].

  14. Field-dependent critical state of high-Tc superconducting strip simultaneously exposed to transport current and perpendicular magnetic field

    SciTech Connect

    Xue, Cun; He, An; Yong, Huadong; Zhou, Youhe

    2013-12-15

    We present an exact analytical approach for arbitrary field-dependent critical state of high-T{sub c} superconducting strip with transport current. The sheet current and flux-density profiles are derived by solving the integral equations, which agree with experiments quite well. For small transport current, the approximate explicit expressions of sheet current, flux-density and penetration depth for the Kim model are derived based on the mean value theorem for integration. We also extend the results to the field-dependent critical state of superconducting strip in the simultaneous presence of applied field and transport current. The sheet current distributions calculated by the Kim model agree with experiments better than that by the Bean model. Moreover, the lines in the I{sub a}-B{sub a} plane for the Kim model are not monotonic, which is quite different from that the Bean model. The results reveal that the maximum transport current in thin superconducting strip will decrease with increasing applied field which vanishes for the Bean model. The results of this paper are useful to calculate ac susceptibility and ac loss.

  15. Pathological bone changes in the mandibles of wild red deer (Cervus elaphus L.) exposed to high environmental levels of fluoride

    PubMed Central

    SCHULTZ, MICHAEL; KIERDORF, UWE; SEDLACEK, FRANTISEK; KIERDORF, HORST

    1998-01-01

    A macroscopic, microscopic and scanning electron microscope study was performed on the pathological bone changes of the mandibles of wild red deer (n=61) exhibiting severe dental fluorosis. The animals originated from a highly fluoride polluted area in Central Europe (Ore mountains and their southern foreland, Czech-German border region) and constituted 11.2% of the studied red deer sample (n=545) from this area. Pathologically increased wear and fracture of fluorosed teeth caused a variety of mandibular bone alterations, including periodontal breakdown, periostitis, osteitis and chronic osteomyelitis. As a further consequence of severe dental attrition, opening of the pulp chamber and formation of periapical abscesses were occasionally observed. In case of severe periodontal breakdown, loss of teeth from the mandibles was found. In addition to the inflammatory bone changes, the occurrence of osteofluorotic alterations was also diagnosed in the specimens with the highest bone fluoride concentrations (>4000 mg F−/kg dry wt). These changes comprised extended apposition of periosteal bone onto the mandibular cortex as well as deformation of the mandibular body, which was attributed to a fluoride-induced osteomalacia. The present study provided circumstantial evidence that, in addition to fluoride induced dental lesions, the occurrence of marked periodontal disease and tooth loss is an important factor responsible for a reduction of life expectancy in severely fluorotic wild red deer. PMID:9877298

  16. Characterization of gypsum crystals exposed to a high CO{sub 2} concentration fog using x-ray

    SciTech Connect

    Carreño-Márquez, I. J. A.; Castillo-Sandoval, I.; Esparza-Ponce, H. E.; Fuentes-Cobas, L.; Montero-Cabrera, M. E.

    2015-07-23

    In Chihuahua State, a little town called Naica has the largest gypsum single crystals in the world. The growth of these structures has been described as a long and stable process developed over thousands of years. Due to the change in the environmental conditions, these crystals could suffer alterations on their surface. In this project we study the cause of possible deterioration of the giant crystals and intend to suggest measures for their preservation. For this sake, our first experiment consists on several gypsum crystals that have been subjected in a climate chamber to a fog at high CO{sub 2} concentration and 51 °C for a period of time of six months, extracting two crystals every 15 days. Then the crystals have been characterized through Grazing Incidence X-Ray Diffraction using a diffractometer PanAlytical X’PertPro with two different detectors; Xe-filled proportional detector and a Pixel 3D detector. The results were compared to determine which technique is the most suitable to study the degradation of gypsum single crystals. In the two cases, we have identified only the gypsum phase, but with different crystal plane orientations.

  17. Biosynthesis of lead nanoparticles by the aquatic water fern, Salvinia minima Baker, when exposed to high lead concentration.

    PubMed

    Castro-Longoria, E; Trejo-Guillén, K; Vilchis-Nestor, A R; Avalos-Borja, M; Andrade-Canto, S B; Leal-Alvarado, D A; Santamaría, J M

    2014-02-01

    Salvinia minima Baker is a small floating aquatic fern that is efficient for the removal and storage of heavy metals such as lead and cadmium. In this study, we report that lead removal by S. minima causes large accumulation of lead inside the cells in the form of nanoparticles (PbNPs). The accumulation pattern of lead was analyzed in both, submerged root-like modified fronds (here named "roots"), and in its aerial leaf-like fronds ("leaves"). Analysis by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) confirmed the biosynthesis of PbNPs by the plant. In both, roots and leaves, PbNPs were found to accumulate almost exclusively at the cell wall and closely associated to the cell membrane. Two types of PbNPs shapes were found in cells of both tissues, those associated to the cell wall were quasi-spherical with 17.2±4.2 nm of diameter, while those associated to the cell membrane/cytoplasm were elongated. Elongated particles were 53.7±29.6 nm in length and 11.1±2.4 nm wide. Infrared spectroscopy (IR) results indicate that cellulose, lignin and pectin are the major components that may be acting as the reducing agents for lead ions; these findings strongly suggest the potential use of this fern to further explore the bio-assisted synthesis of heavy metal nanostructures. PMID:24211828

  18. Working group report on advanced high-voltage high-power and energy-storage space systems

    NASA Technical Reports Server (NTRS)

    Cohen, H. A.; Cooke, D. L.; Evans, R. W.; Hastings, D.; Jongeward, G.; Laframboise, J. G.; Mahaffey, D.; Mcintyre, B.; Pfizer, K. A.; Purvis, C.

    1986-01-01

    Space systems in the future will probably include high-voltage, high-power energy-storage and -production systems. Two such technologies are high-voltage ac and dc systems and high-power electrodynamic tethers. The working group identified several plasma interaction phenomena that will occur in the operation of these power systems. The working group felt that building an understanding of these critical interaction issues meant that several gaps in our knowledge had to be filled, and that certain aspects of dc power systems have become fairly well understood. Examples of these current collection are in quiescent plasmas and snap over effects. However, high-voltage dc and almost all ac phenomena are, at best, inadequately understood. In addition, there is major uncertainty in the knowledge of coupling between plasmas and large scale current flows in space plasmas. These gaps in the knowledge are addressed.

  19. Modulation of GSH with exogenous agents leads to changes in glyoxalase 1 enzyme activity in VL-17A cells exposed to chronic alcohol plus high glucose.

    PubMed

    Kumar, S Mathan; Swaminathan, Kavitha; Clemens, Dahn L; Dey, Aparajita

    2014-02-01

    Gluthathione (GSH) is a major cellular antioxidant. The present study utilizing VL-17A cells exposed to chronic alcohol plus high glucose investigated the changes in oxidative stress, toxicity, and glyoxalase 1 activity as a detoxification pathway due to changes in GSH level through GSH supplementation with N-acetyl cysteine (NAC) or ursodeoxycholic acid (UDCA) and its depletion through buthionine sulfoximine (BSO) or diethyl maleate (DEM). Glyoxalase 1 plays an important role in detoxification of methylglyoxal which is formed as a precursor of advanced glycated end products formed due to high glucose mediated oxidative stress. Significant changes in glyoxalase 1 activity utilizing methylglyoxal or glyoxal as substrates occurred with NAC or UDCA or BSO or DEM supplementation in chronic alcohol plus high glucose treated VL-17A cells. NAC or UDCA administration in chronic alcohol plus high glucose treated VL-17A cells increased viability and decreased ROS levels, lipid peroxidation and 3-nitrotyrosine adduct formation. Similarly, GSH depletion with BSO or DEM had an opposite effect on the parameters in chronic alcohol plus high glucose treated VL-17A cells. In conclusion, modulation of GSH with NAC or UDCA or BSO or DEM leads to significant changes in oxidative stress, glyoxalase 1 enzyme activity and toxicity in chronic alcohol plus high glucose treated VL-17A cells.

  20. High resolution and dynamic imaging of biopersistence and bioreactivity of extra and intracellular MWNTs exposed to microglial cells

    PubMed Central

    Gonzalez Carter, Daniel A.; Motskin, Michael; Pienaar, Ilse S.; Chen, Shu; Hu, Sheng; Ruenraroengsak, Pakatip; Ryan, Mary P.; Shaffer, Milo S. P.; Dexter, David T.

    2016-01-01

    Multi-walled carbon nanotubes (MWNTs) are increasingly being developed both as neuro-therapeutic drug delivery systems to the brain and as neural scaffolds to drive tissue regeneration across lesion sites. MWNTs with different degrees of acid oxidation may have different bioreactivities and propensities to aggregate in the extracellular environment, and both individualised and aggregated MWNTs may be expected to be found in the brain. Before practical application, it is vital to understand how both aggregates and individual MWNTs will interact with local phagocytic immune cells, the microglia, and ultimately to determine their biopersistence in the brain. The processing of extra- and intracellular MWNTs (both pristine and when acid oxidised) by microglia was characterised across multiple length scales by correlating a range of dynamic, quantitative and multi-scale techniques, including: UV-vis spectroscopy, light microscopy, focussed ion beam scanning electron microscopy and transmission electron microscopy. Dynamic, live cell imaging revealed the ability of microglia to break apart and internalise micron-sized extracellular agglomerates of acid oxidised MWNT, but not pristine MWNTs. The total amount of MWNTs internalised by, or strongly bound to, microglia was quantified as a function of time. Neither the significant uptake of oxidised MWNTs, nor the incomplete uptake of pristine MWNTs affected microglial viability, pro-inflammatory cytokine release or nitric oxide production. However, after 24 hrs exposure to pristine MWNTs, a significant increase in the production of reactive oxygen species was observed. Small aggregates and individualised oxidised MWNTs were present in the cytoplasm and vesicles, including within multilaminar bodies, after 72 hours. Some evidence of morphological damage to oxidised MWNT structure was observed including highly disordered graphitic structures, suggesting possible biodegradation. This work demonstrates the utility of dynamic

  1. The Mt. Perkins block, northwestern Arizona: An exposed cross section of a synextensional volcano in highly extended terrane

    SciTech Connect

    Faulds, J.E. . Dept. of Geology)

    1993-04-01

    Despite widespread and voluminous middle to late Tertiary volcanism in the Basin and Range province, relatively few volcanic centers have been located, especially in highly extended regions. Although large-magnitude tilting and structural dismemberment generally obscure conventional exposures of volcanic centers, they can potentially provide cross sectional views of major volcanic edifices. In the northern Colorado River extensional corridor, the steeply (90[degree]) W-tilted Mt. Perkins block incorporates a cross-sectional view of part of a major Miocene volcanic center. In ascending structural order from east to west, the Mt. Perkins block includes (a) a 15.96 Ma quartz monzonite to diorite pluton emplaced in Proterozoic gneiss, (b) a 20 km long, NNW-striking, gently to moderately (0--45[degree]) E-dipping felsic dike swarm (one dike dated at 14.7 Ma), (c) a nonconformity at the base of the Miocene volcanic section, (d) basaltic andesite flows and dacite flows and domes, (e) a 300--1,500 m thick section of rhyolite flows, surges, and tuffs bracketed between 16.4 and 14.4 Ma, and (f) capping basalt flows. Tilts decrease from 90 to 30 W between the base of the rhyolite section and upper basalt flows. Geologic and paleomagnetic data indicate 40--90 of W-tilting of the dike swarm and pluton. The felsic dike swarm invades the lower part of the volcanic section and terminates upward in the coeval sequence of rhyolites. In addition, the dike swarm and rhyolite section terminate along-strike in roughly the same area. Restoration places the rhyolites above the dike swarm, which in turn is situated directly above the pluton. These data indicate a genetic tie between at least the felsic dike swarm and thick sequence of rhyolites. Geochemical fingerprinting of the lavas, dike swarm, and pluton is underway to test the tilted volcano'' hypothesis.

  2. The dependence of radiation enhancement effect on the concentration of gold nanoparticles exposed to low- and high-LET radiations.

    PubMed

    Liu, Yan; Liu, Xi; Jin, Xiaodong; He, Pengbo; Zheng, Xiaogang; Dai, Zhongying; Ye, Fei; Zhao, Ting; Chen, Weiqiang; Li, Qiang

    2015-05-01

    We examined the dependence of hydroxyl radical production on the concentration of 15 nm citrate-capped AuNPs and dose using coumarin-3-carboxylic acid in phosphate buffered saline (PBS), and investigated the radiosensitisation of different concentration AuNPs on human cervix carcinoma HeLa cells through clonogenic survival assay for X-rays and carbon ions. The enhancement factor of AuNPs for hydroxyl radical production reached a maximum 3.66 for X-rays at the concentration of 0.1 μg/mL while the maximum was 5.52 for carbon ions in presence of 1.0 μg/mL AuNPs in PBS. At 50% survival level, the sensitizer enhancement ratios of X-rays and carbon ions varied from 1.14 to 2.88 and from 1.27 to 1.44, respectively, when cells were co-cultured with 1.5-15.0 μg/mL AuNPs. Our data indicate AuNPs showed radiosensitisation in terms of hydroxyl radical production and cell killing for low- and high-LET radiations. The concentration of AuNPs in PBS and cells played an important role in radiosensitizing effect. Based on the fact-the AuNPs in PBS could improve the production of hydroxyl radical and no accumulation of cells in the G2/M phase was observed, we deduce that the increment of hydroxyl radical production with AuNPs provided a mechanism for radiosensitisation.

  3. High resolution and dynamic imaging of biopersistence and bioreactivity of extra and intracellular MWNTs exposed to microglial cells.

    PubMed

    Goode, Angela E; Gonzalez Carter, Daniel A; Motskin, Michael; Pienaar, Ilse S; Chen, Shu; Hu, Sheng; Ruenraroengsak, Pakatip; Ryan, Mary P; Shaffer, Milo S P; Dexter, David T; Porter, Alexandra E

    2015-11-01

    Multi-walled carbon nanotubes (MWNTs) are increasingly being developed both as neuro-therapeutic drug delivery systems to the brain and as neural scaffolds to drive tissue regeneration across lesion sites. MWNTs with different degrees of acid oxidation may have different bioreactivities and propensities to aggregate in the extracellular environment, and both individualised and aggregated MWNTs may be expected to be found in the brain. Before practical application, it is vital to understand how both aggregates and individual MWNTs will interact with local phagocytic immune cells, the microglia, and ultimately to determine their biopersistence in the brain. The processing of extra- and intracellular MWNTs (both pristine and when acid oxidised) by microglia was characterised across multiple length scales by correlating a range of dynamic, quantitative and multi-scale techniques, including: UV-vis spectroscopy, light microscopy, focussed ion beam scanning electron microscopy and transmission electron microscopy. Dynamic, live cell imaging revealed the ability of microglia to break apart and internalise micron-sized extracellular agglomerates of acid oxidised MWNTs, but not pristine MWNTs. The total amount of MWNTs internalised by, or strongly bound to, microglia was quantified as a function of time. Neither the significant uptake of oxidised MWNTs, nor the incomplete uptake of pristine MWNTs affected microglial viability, pro-inflammatory cytokine release or nitric oxide production. However, after 24 h exposure to pristine MWNTs, a significant increase in the production of reactive oxygen species was observed. Small aggregates and individualised oxidised MWNTs were present in the cytoplasm and vesicles, including within multilaminar bodies, after 72 h. Some evidence of morphological damage to oxidised MWNT structure was observed including highly disordered graphitic structures, suggesting possible biodegradation. This work demonstrates the utility of dynamic

  4. Prevalence of Diabetes, Obesity and Dyslipidaemia in Persons within High and Low Income Groups Living in North and South Trinidad

    PubMed Central

    Rahming, Valendrea; Raghunanan, Yudestri; Raghoonath, Chandani; Rahman, Adriel; Rajh, Dillon; Rambadan, Sherry; Ramdass, Nandini

    2016-01-01

    Introduction Diabetes Mellitus, obesity and dyslipidaemia are metabolic disorders characterized by similar risk factors, complications and outcomes including stroke, insulin resistance, MI and even death. Studies have indicated that impoverished and low income areas of developing countries are more prone to increasing obesity which when uncontrolled can lead to diabetes mellitus and dyslipidaemia. Aim The study was aimed to compare the prevalence of diabetes mellitus, obesity and dyslipidaemia in high and low income groups of North and South Trinidad, to determine factors that contribute to its prevalence and to observe any associations between the three aforementioned diseases. Materials and Methods The cross-sectional study was conducted on 200 participants who visited the two major hospitals at south and north Trinidad where the mean differences between fasting glucose, lipid profile, BMI, waist and hip ratio and blood pressure of both diabetic and non-diabetic participants were obtained via questionnaires and then analysed using SPSS. Results Residents of south Trinidad showed a higher proportion of persons with diabetes and dyslipidaemia at 68.6% and 52% when compared to 28.6% and 27% respectively for the north population. Those from north Trinidad showed a higher prevalence of obesity at 45.9% with higher income levels. About 17.3% participants smoked or were exposed to cigarettes in north compared to 9.8% of participants whom smoked or were exposed to cigarettes in south. North had 2% of alcohol consumed daily and 3.9% consumed alcohol daily in south. In north, 21.4% of participants were stressed when compared to 18.6% from south. Conclusion A significant correlation was established between cholesterol, LDL and triglycerides which lead to the conclusion that obesity is caused by dyslipidaemia. Also, our study concluded that stress and dyslipidaemia are income related. PMID:27437244

  5. Prevalence of HCV among the high risk groups in Khyber Pakhtunkhwa

    PubMed Central

    2011-01-01

    Hepatitis C is an infectious disease, caused by blood borne pathogen; the Hepatitis C Virus. In this study we analyzed blood samples collected from various risk groups for the prevalence of anti-HCV and active HCV infection with the help of Immunochromtographic tests and nested PCR. The prevalence of active HCV infection among the high risk groups was 15.57% (26/167). The prevalence of HCV in individual risk groups was 15%, 28%, 8%, 14.28% and 14.28% in the case of thalassemics, dialysis, major surgery group, dental surgery group and injection drug users respectively. Our analysis reveals the fact that health care facilities in the Khyber Pakhtunkhwa province of Pakistan are contributing a great deal towards the spread of HCV infection. PMID:21663685

  6. Impact of High Velocity Interactions on Galaxy Evolution in Galaxy Groups

    NASA Astrophysics Data System (ADS)

    Machacek, Marie E.; Jones, C.; Forman, W. R.; Kraft, R. P.; Ashby, M. L.; Hardcastle, M. J.

    2007-05-01

    Galaxy interactions in cool groups dominate galaxy evolution at high redshift. Observations of galaxies interacting in nearby galaxy groups, where the same dynamical processes that transform galaxies at high redshift can be studied in detail, are critical to our understanding of galaxy and group evolution. X-ray observations of hot gas features, e.g. surface brightness edges and wakes, reveal that high velocity interactions play a significant role in the transformation of galaxies in groups, yet, because these encounters are difficult to identify in other wavebands, few have been studied. We present two case studies of high velocity galaxy-galaxy and galaxy-gas interactions in galaxy groups: NGC4782(3C278) and NGC4783 in LGG316, and NGC6872 and NGC6876 in the Pavo group. From Chandra and XMM-Newton X-ray data, we measure the hot gas temperature, density and metal abundance in the galaxies and the intragroup medium (IGM) to characterize the thermodynamic state of the group, constrain 3D motions of the galaxies through the IGM, and determine the dominant processes transferring matter and energy between the galaxy and group gas. We compare these results with VLA observations of NGC4782/3 and Spitzer IRAC observations of NGC6872 and NGC6876 to study the impact of these interactions on nuclear activity, radio jet evolution, and star formation in these galaxies, and on the heating and enrichment of the IGM. This work was supported in part by the Smithsonian Institution, the Chandra Science Center, NASA contracts AR5-6011X, GO6-7068X, NNX06AG34G, JPL1279244 and the Royal Society.

  7. Mom Power: preliminary outcomes of a group intervention to improve mental health and parenting among high-risk mothers.

    PubMed

    Muzik, Maria; Rosenblum, Katherine L; Alfafara, Emily A; Schuster, Melisa M; Miller, Nicole M; Waddell, Rachel M; Stanton Kohler, Emily

    2015-06-01

    Maternal psychopathology and traumatic life experiences may adversely impact family functioning, the quality of the parent-child relationship and the attachment bond, placing the child's early social-emotional development at risk. Attachment-based parenting interventions may be particularly useful in decreasing negative outcomes for children exposed to risk contexts, yet high risk families frequently do not engage in programs to address mental health and/or parenting needs. This study evaluated the effects of Mom Power (MP), a 13-session parenting and self-care skills group program for high-risk mothers and their young children (age <6 years old), focused on enhancing mothers' mental health, parenting competence, and engagement in treatment. Mothers were referred from community health providers for a phase 1 trial to assess feasibility, acceptability, and pilot outcomes. At baseline, many reported several identified risk factors, including trauma exposure, psychopathology, poverty, and single parenthood. Ninety-nine mother-child pairs were initially recruited into the MP program with 68 women completing and providing pre- and post-self-report measures assessing demographics and trauma history (pre-assessment only), maternal mental health (depression and post-traumatic stress disorder (PTSD)), parenting, and intervention satisfaction. Results indicate that MP participation was associated with reduction in depression, PTSD, and caregiving helplessness. A dose response relationship was evident in that, despite baseline equivalence, women who attended ≥70 % of the 10 groups (completers; N = 68) improved on parenting and mental health outcomes, in contrast to non-completers (N = 12). Effects were most pronounced for women with a mental health diagnosis at baseline. The intervention was perceived as helpful and user-friendly. Results indicate that MP is feasible, acceptable, and holds promise for improving maternal mental health and parenting competence among

  8. Mom Power: Preliminary Outcomes of a Group Intervention to Improve Mental Health and Parenting Among High-Risk Mothers

    PubMed Central

    Muzik, Maria; Rosenblum, Katherine L.; Alfafara, Emily A.; Schuster, Melisa M.; Miller, Nicole M.; Waddell, Rachel M.; Kohler, Emily Stanton

    2015-01-01

    Purpose Maternal psychopathology and traumatic life experiences may adversely impact family functioning, the quality of the parent-child relationship and the attachment bond, placing the child’s early social-emotional development at risk. Attachment-based parenting interventions may be particularly useful in decreasing negative outcomes for children exposed to risk contexts, yet high risk families frequently do not engage in programs to address mental health and/or parenting needs. This study evaluated the effects of Mom Power (MP), a 13-session parenting and self-care skills group program for high-risk mothers and their young children (age <6 years old), focused on enhancing mothers’ mental health, parenting competence and engagement in treatment. Methods Mothers were referred from community health providers for a Phase 1 trial to assess feasibility, acceptability and pilot outcomes. At baseline, many reported several identified risk factors, including trauma exposure, psychopathology, poverty and single parenthood. 99 mother-child pairs were initially recruited into the MP program with 68 women completing and providing pre- and post- self-report measures assessing demographics and trauma history (pre-assessment only), maternal mental health (depression and PTSD), parenting and intervention satisfaction. Results Results indicate that MP participation was associated with reduction in depression, PTSD and caregiving helplessness. A dose response relationship was evident in that, despite baseline equivalence, women who attended ≥70% of the 10 groups (completers; N=68) improved on parenting and mental health outcomes, in contrast to non-completers (N=12). Effects were most pronounced for women with a mental health diagnosis at baseline. The intervention was perceived as helpful and user-friendly. Conclusions Results indicate that MP is feasible, acceptable and holds promise for improving maternal mental health and parenting competence among high-risk dyads

  9. Mom Power: preliminary outcomes of a group intervention to improve mental health and parenting among high-risk mothers.

    PubMed

    Muzik, Maria; Rosenblum, Katherine L; Alfafara, Emily A; Schuster, Melisa M; Miller, Nicole M; Waddell, Rachel M; Stanton Kohler, Emily

    2015-06-01

    Maternal psychopathology and traumatic life experiences may adversely impact family functioning, the quality of the parent-child relationship and the attachment bond, placing the child's early social-emotional development at risk. Attachment-based parenting interventions may be particularly useful in decreasing negative outcomes for children exposed to risk contexts, yet high risk families frequently do not engage in programs to address mental health and/or parenting needs. This study evaluated the effects of Mom Power (MP), a 13-session parenting and self-care skills group program for high-risk mothers and their young children (age <6 years old), focused on enhancing mothers' mental health, parenting competence, and engagement in treatment. Mothers were referred from community health providers for a phase 1 trial to assess feasibility, acceptability, and pilot outcomes. At baseline, many reported several identified risk factors, including trauma exposure, psychopathology, poverty, and single parenthood. Ninety-nine mother-child pairs were initially recruited into the MP program with 68 women completing and providing pre- and post-self-report measures assessing demographics and trauma history (pre-assessment only), maternal mental health (depression and post-traumatic stress disorder (PTSD)), parenting, and intervention satisfaction. Results indicate that MP participation was associated with reduction in depression, PTSD, and caregiving helplessness. A dose response relationship was evident in that, despite baseline equivalence, women who attended ≥70 % of the 10 groups (completers; N = 68) improved on parenting and mental health outcomes, in contrast to non-completers (N = 12). Effects were most pronounced for women with a mental health diagnosis at baseline. The intervention was perceived as helpful and user-friendly. Results indicate that MP is feasible, acceptable, and holds promise for improving maternal mental health and parenting competence among

  10. MOCVD growth of group III nitrides for high power, high frequency applications

    NASA Astrophysics Data System (ADS)

    di Forte Poisson, M.-A.; Magis, M.; Tordjman, M.; Sarazin, N.; di Persio, J.

    2005-02-01

    This paper reports on the LP-MOCVD growth optimisation of bulk GaN, GaAlN materials and GaAlN/GaN heterostructures grown on Sapphire and Silicon Carbide substrates for MESFET and HEMT applications, and on the device performances obtained with these structures. High purity and high resistivity GaN grown on sapphire and Silicon Carbide has been obtained. GaN/Al2O3 MESFETs based on such high purity GaN buffer layers, have exhibited very promising static and microwave performances: high beakdown voltage 200 V, ft = 12 GHz, fmax = 25 GHz and CW output power in excess of 2.2 W/mm at 2 GHz.. They have shown the best low frequency noise performances, with the lowest Hooge's parameter as compared to previous values reported in the literature for different GaN-based FETs (HFETs and HEMTs). The main mechanisms involved in the growth of GaAlN/GaN alloys have been studied and their impact on the physical properties of these materials determined. A parasitic reaction was clearly identified to occur in the gas phase between TMA and NH3, with a strong influence on the growth rate and the aluminium incorporation. The SiC substrate surface preparation (both ex-situ and in-situ) and the nucleation layer growth conditions (growth temperature, thickness, composition and strain) have been found to be key steps of the GaAlN/GaN/SiC growth process. Static characteristics of the devices such as maximum drain current Idss or pinch-off voltage have been correlated with the nucleation layer composition of the HEMT structure and the defect density of the SiC substrate. The devices performances related to our first GaAlN/GaN HEMT structures grown on Sapphire and Silicon Carbide have confirmed the high potentiality of GaN and related alloys for high power microwave transistors. Load-Pull measurements performed at 2 GHz on devices related to GaAlN/GaN/Al2O3 HEMT structures, have shown a remarkably high output power density (4.4 W/mm) and absolute power level (3.2 W

  11. The synthesis of monomers with pendent ethynyl group for modified high performance thermoplastics

    NASA Technical Reports Server (NTRS)

    Nwokogu, Godson C.; Antoine, Miquel D.; Ansong, Omari

    1992-01-01

    The objectives of this project were to develop synthetic schemes for the following classes of modified monomers: (1) difunctional triarylethanes with pendent acetylenic groups; and (2) tertiary aspartimides with terminal acetylene groups at the two ends. Our efforts have resulted in the successful development of high yield schemes for the syntheses of several diamino and bisphenolic analogs of difunctional triarylethanes with pendent ethynyl group. A scheme for one new tertiary aspartimide was also established. Multi-gram samples of all prepared new monomers were provided to our technical contact at NASA-LaRC and preliminary polymerization studies were encouraging. Details of the accomplished work within the last four years are described.

  12. Immunization of high-risk paediatric populations: Central European Vaccination Awareness Group recommendations.

    PubMed

    Richter, Darko; Anca, Ioana; André, Francis E; Bakir, Mustafa; Chlibek, Roman; Čižman, Milan; Mangarov, Atanas; Mészner, Zsófia; Pokorn, Marko; Prymula, Roman; Salman, Nuran; Simurka, Pavol; Tamm, Eda; Tešović, Goran; Urbančíková, Ingrid; Usonis, Vytautas; Wysocki, Jacek; Zavadska, Dace; Central European Vaccination Awareness Group

    2014-06-01

    Over the last decade, childhood immunization has substantially reduced morbidity and mortality from vaccine-preventable diseases. However, particular paediatric risk groups, such as those with comorbidities, may not be adequately vaccinated despite being more susceptible to complications and death from certain infectious diseases. This may be due to lack of immunization recommendations, lack of awareness, or incomplete adherence to existing guidelines. Furthermore, recommendations for immunization can be inconsistent across Europe. An expanded initiative from the Central European Vaccination Awareness Group aims to raise awareness of the different high-risk paediatric groups, differentiate them according to their specific risk, and formalise a guidance statement for the immunization of each population.

  13. Relations between high and low power groups: the importance of legitimacy.

    PubMed

    Hornsey, Matthew J; Spears, Russell; Cremers, Iris; Hogg, Michael A

    2003-02-01

    Using a social identity perspective, two experiments examined the effects of power and the legitimacy of power differentials on intergroup bias. In Experiment 1, 125 math-science students were led to believe that they had high or low representation in a university decision-making body relative to social-science students and that this power position was either legitimate or illegitimate. Power did not have an independent effect on bias; rather, members of both high and low power groups showed more bias when the power hierarchy was illegitimate than when it was legitimate. This effect was replicated in Experiment 2 (N = 105). In addition, Experiment 2 showed that groups located within an unfair power hierarchy expected the superordinate power body to be more discriminatory than did those who had legitimately high or low power. The results are discussed in terms of their implications for group relations.

  14. Molecular dynamics simulation of the formation, growth and bursting of bubbles in tungsten exposed to high fluxes of low energy deuterium

    NASA Astrophysics Data System (ADS)

    Liu, Shengguang; Dai, Shuyu; Sang, Chaofeng; Sun, Jizhong; Stirner, Thomas; Wang, Dezhen

    2015-08-01

    Molecular dynamics simulations are carried out to investigate the formation, growth and bursting of bubbles in tungsten exposed to the irradiation of an extremely high deuterium flux. It is found that the bubbles form in the region near the location of the implanted ion distribution peaks, and that the effect of the substrate temperature on the bubble formation depth is negligible; it is also found that the percentage of deuterium that is found in D2 molecules increases as the bubble grows, and that the evolution of the bubble's internal pressure is strongly associated with the properties of its surrounding structure. The simulations display the development of a dome-shaped structure at the tungsten surface during the bubble growth. The merging of two deuterium bubbles is also observed. The present simulations also show that the bubble bursts by generating a partially opened lid, which has already been observed in previous independent experiments.

  15. A prospective study of the potential moderating role of social support in preventing marginalization among individuals exposed to bullying and abuse in junior high school.

    PubMed

    Strøm, Ida Frugård; Thoresen, Siri; Wentzel-Larsen, Tore; Sagatun, Åse; Dyb, Grete

    2014-10-01

    Negative physical and psychological long-term consequences of abuse and bullying are well documented. It is reasonable to assume that abuse and bullying early in life also may have an impact on the ability to work and stay economically independent later in life, but such prospective studies are lacking. This study investigates the consequences of exposure to abuse and bullying in junior high school, as measured by receiving long-term social welfare benefits in young adulthood. In addition, it explores the potential protective role of social support. Self-reported data from 13,633 (50.3% female) junior high school students were linked to registry data on their use of social welfare benefits from the age of 18 and for eight consecutive years. Cox regression analyses were applied to test the relationship between exposure to life adversities and the use of social welfare benefits, and the potential moderating role of social support. The analyses showed that individuals exposed to abuse and bullying had an increased likelihood of receiving social-welfare benefits compared with individuals not exposed to these types of abuse. Exposure to multiple types of abuse led to a higher likelihood of using social welfare benefits compared with single types of abuse and no abuse. The findings on the potential moderating role of social support were mixed, depending on the source of social support. Family support and classmate relationships were protective in reducing the likelihood of the use of social welfare benefits, whereas peer and teachers' support showed inconsistent patterns. These results are promising in terms of preventing the long-term negative consequences of abuse and bullying.

  16. Studying high redshift galaxy groups with the Athena Wide-Field-Imager

    NASA Astrophysics Data System (ADS)

    Pacaud, Florian; Reiprich, Thomas; Ramos Ceja, Miriam Elizabeth; Lovisari, Lorenzo

    2016-07-01

    In this contribution, we will discuss the potential of Athena to study high redshift galaxy groups (1groups in Athena WFI observations and our ability to identify them as extended sources among the numerous active galactic nuclei (AGN) at similar fluxes. Our analysis also includes the determination of the physical properties of these galaxy groups (average gas temperature, luminosity). Based on these tools, we discuss the science achievable with such systems thanks to Athena and its dependance on the final instrumental set-up. In particular, we investigate the impact of different levels of contamination by AGNs and assumptions on the luminosity of the groups as a function of their mass.

  17. Tropolone as a High-Performance Robust Anchoring Group for Dye-Sensitized Solar Cells.

    PubMed

    Higashino, Tomohiro; Fujimori, Yamato; Sugiura, Kenichi; Tsuji, Yukihiro; Ito, Seigo; Imahori, Hiroshi

    2015-07-27

    A tropolone group has been employed for the first time as an anchoring group for dye-sensitized solar cells (DSSCs). The DSSC based on a porphyrin, YD2-o-C8T, with a tropolone moiety exhibited a power-conversion efficiency of 7.7 %, which is only slightly lower than that observed for a reference porphyrin, YD2-o-C8, with a conventional carboxylic group. More importantly, YD2-o-C8T was found to be superior to YD2-o-C8 with respect to DSSC durability and binding ability to TiO2 . These results unambiguously demonstrate that tropolone is a highly promising dye-anchoring group for DSSCs in terms of device durability as well as photovoltaic performance.

  18. Review of Social Skills Training Groups for Youth with Asperger Syndrome and High Functioning Autism

    ERIC Educational Resources Information Center

    Cappadocia, M. Catherine; Weiss, Jonathan A.

    2011-01-01

    Although social skills deficits represent core symptoms of Asperger Syndrome and High Functioning Autism, there is limited research investigating the empirical validity of social skills interventions currently being used with these populations. This literature review compares three types of social skills training groups: traditional, cognitive…

  19. High Energy Accelerator and Colliding Beam User Group: Progress report, March 1, 1988--February 28, 1989

    SciTech Connect

    Not Available

    1988-09-01

    This report discusses work carried out by the High Energy Accelerator and Colliding Beam User Group at the University of Maryland. Particular topics discussed are: OPAL experiment at LEP; deep inelastic muon interactions; B physics with the CLEO detector at CESR; further results from JADE; and search for ''small'' violation of the Pauli principle. (LSP)

  20. Internet-based Group Relations: A High School Peace Educational Project in Israel.

    ERIC Educational Resources Information Center

    Yablon, Yaacov B.; Katz, Yaacov J.

    2001-01-01

    Describes how Internet-based group communication was used as the major strategy to promote the societal values of understanding, equality, tolerance, and peace between Jewish and Bedouin Arab high school students in Israel. Discusses changes in student attitudes and considers the prognosis for long-term change and cooperation between the two…

  1. Urinary Cortisol Circadian Rhythm in a Group of High-Functioning Children with Autism.

    ERIC Educational Resources Information Center

    Richdale, Amanda L.; Prior, Margot R.

    1992-01-01

    This study found no evidence for abnormal temporal placement of the basal urinary cortisol circadian rhythm in a group of 18 high-functioning children (ages 4-14) with autism. There was a tendency toward cortisol hypersecretion during the day, predominantly in autistic children who were integrated into the normal school system. (Author/JDD)

  2. A Guide to Group Counseling in Junior High School. Futureprint Counseling Component.

    ERIC Educational Resources Information Center

    Guillen, Mary A.

    Designed for junior high school counselors, the guide offers an outline for facilitating group counseling sessions. Intended to be held one class period a week for eight weeks, the sessions aim toward potential improvement in self-esteem, personal relationships, peer understanding, self-awareness, academic performance, and social skills. Each…

  3. The Effect of the Vocational Exploration Group on Career Decision Making Behaviors of High School Students.

    ERIC Educational Resources Information Center

    Torrez, Daniel S.; And Others

    1979-01-01

    In this study the effect of the Vocational Exploration Group on high school students was investigated, using measures of attitude, information-seeking behaviors and knowledge of interests and skills. Analyses of variance showed that treatment subjects had significantly higher scores on the knowledge measure than did control subjects. (Author)

  4. A Support Group Intervention for At-Risk Female High School Students.

    ERIC Educational Resources Information Center

    Houck, Gail M.; Darnell, Susan; Lussman, Sarah

    2002-01-01

    Pre- and post-intervention, female high school students with signs of depression completed surveys about risk and protective factors. Students participated in a weekly support group that enhanced coping skills and provided emotional support. Before the intervention, students were at risk for suicide. At the end, there was a 55 percent reduction in…

  5. Comparative genomic hybridisation divides retinoblastomas into a high and a low level chromosomal instability group

    PubMed Central

    van der Wal, J E; Hermsen, M A J A; Gille, H J P; Schouten-Van Meeteren, N Y N; Moll, A C; Imhof, S M; Meijer, G A; Baak, J P A; van der Valk, P

    2003-01-01

    Background: Retinoblastoma is the most common intraocular malignancy in childhood and is responsible for approximately 1% of all deaths caused by childhood cancer. Aims/methods: Comparative genomic hybridisation was performed on 13 consecutive, histologically confirmed retinoblastomas to analyse patterns of chromosomal changes and correlate these to clinicopathological variables. Six cases were hereditary and seven cases were sporadic. Results: In 11 of the 13 tumours chromosomal abnormalities were detected, most frequently gains. Frequent chromosomal gains concerned 6p (46%), 1q (38%), 2p, 9q (30%), 5p, 7q, 10q, 17q, and 20q (23%). Frequent losses occurred at Xq (46%), 13q14, 16q, and 4q (23%). High level copy number gains were found at 5p15 and 6p11–12. A loss at 13q14 occurred in three cases only. Relatively few events occurred in the hereditary cases (27) compared with the non-hereditary cases (70 events). The number of chromosomal aberrations in these 13 retinoblastomas showed a bimodal distribution. Seven tumours showed less than four chromosomal aberrations, falling into a low level chromosomal instability (CIN) group, and six tumours showed at least eight aberrations, falling into a high level CIN group. In the low level CIN group the mean age was half that seen in the high level CIN group, there were less male patients, and there were more hereditary and bilateral cases. Microsatellite instability was not detected in either of the two groups. Conclusion: Despite the complex pattern of genetic changes in retinoblastomas, certain chromosomal regions appear to be affected preferentially. On the basis of the number of genetic events, retinoblastomas can be divided in low and a high level chromosomal instability groups, which have striking differences in clinical presentation. PMID:12499428

  6. High-Frequency Heart Rate Variability Linked to Affiliation with a New Group

    PubMed Central

    Sahdra, Baljinder K.; Ciarrochi, Joseph; Parker, Philip D.

    2015-01-01

    This study tests the hypothesis that high levels of high-frequency heart rate variability (HF-HRV) predisposes individuals to affiliate with new groups. Resting cardiac physiological recordings were taken before and after experimental sessions to measure trait high-frequency heart rate variability as an index of dispositional autonomic influence on heart rate. Following an experimental manipulation of priming of caring-related words, participants engaged in a minimal group paradigm, in which they imagined being a member of one of two arbitrary groups, allocated money to members of the two groups, and rated their affiliation with the groups. High levels of HF-HRV were associated with ingroup favouritism while allocating money, an effect largely attributable to a positive relationship between HF-HRV and allocation of money to the ingroup, and less due to a negative relationship between HF-HRV and money allocation to the outgroup. HF-HRV was also associated with increased self-reported affiliation feelings for the ingroup but was unrelated to feelings towards the outgroup. These effects remained substantial even after controlling for age, gender, BMI, mood, caffeine consumption, time of day of data collection, smoking and alcohol behaviour, and respiration rate. Further, the effects were observed regardless of whether participants were primed with caring-related words or not. This study is the first to bridge a long history of research on ingroup favouritism to the relatively recent body of research on cardiac vagal tone by uncovering a positive association between HF-HRV and affiliation with a novel group. PMID:26106891

  7. High-Frequency Heart Rate Variability Linked to Affiliation with a New Group.

    PubMed

    Sahdra, Baljinder K; Ciarrochi, Joseph; Parker, Philip D

    2015-01-01

    This study tests the hypothesis that high levels of high-frequency heart rate variability (HF-HRV) predisposes individuals to affiliate with new groups. Resting cardiac physiological recordings were taken before and after experimental sessions to measure trait high-frequency heart rate variability as an index of dispositional autonomic influence on heart rate. Following an experimental manipulation of priming of caring-related words, participants engaged in a minimal group paradigm, in which they imagined being a member of one of two arbitrary groups, allocated money to members of the two groups, and rated their affiliation with the groups. High levels of HF-HRV were associated with ingroup favouritism while allocating money, an effect largely attributable to a positive relationship between HF-HRV and allocation of money to the ingroup, and less due to a negative relationship between HF-HRV and money allocation to the outgroup. HF-HRV was also associated with increased self-reported affiliation feelings for the ingroup but was unrelated to feelings towards the outgroup. These effects remained substantial even after controlling for age, gender, BMI, mood, caffeine consumption, time of day of data collection, smoking and alcohol behaviour, and respiration rate. Further, the effects were observed regardless of whether participants were primed with caring-related words or not. This study is the first to bridge a long history of research on ingroup favouritism to the relatively recent body of research on cardiac vagal tone by uncovering a positive association between HF-HRV and affiliation with a novel group. PMID:26106891

  8. Childhood Adversity Among Institutionalized Male Juvenile Offenders and Other High-Risk Groups Without Offense Records in Portugal.

    PubMed

    Pinto, Ricardo José; Fernandes, Ana Isabel; Mesquita, Cristina; Maia, Ângela Costa

    2015-01-01

    The literature has shown that delinquent adolescents report high rates of childhood adversity and family dysfunction. However, it is important to know both the degree of adversity among delinquent adolescents in comparison with other high-risk samples and the contribution of each single form of adversity to this comparison. The purpose of this study was to evaluate childhood adversity, psychopathology, and risk behaviors among 4 high-risk groups, including incarcerated delinquent youths. The participants were 120 male youths between 13 and 19 years old (M = 16.18, SD = 1.26), including 30 youths who were arrested and held in detention centers as a consequence of violent crimes; 30 youths who were identified by Child Protective Services (CPS) and remained with their families; 30 youths who were identified by CPS, removed from their homes, and placed in child and youth residential care; and 30 youths who were randomly selected from schools. The incarcerated youths reported significantly more adversity, global psychopathology, and global index of risk behaviors. When considering each risk behavior, the incarcerated youths reported higher percentages of alcohol abuse, drug use, early smoking initiation, physical assault, carrying weapons, early initiation of sexual intercourse, sexual intercourse under the influence of drugs, and sexual intercourse without condom use. The logistic regression analyses showed that only emotional neglect was significantly associated with delinquency. This study suggests that delinquent youths are exposed to a great magnitude of adversities in childhood, with emotional neglect as an independent risk factor for delinquency. In addition, these youths have higher rates of psychopathology and risk behaviors compared to other high-risk samples. PMID:26159627

  9. Effects of melatonin and green-wavelength LED light on the physiological stress and immunity of goldfish, Carassius auratus, exposed to high water temperature.

    PubMed

    Jung, Seo Jin; Kim, Na Na; Choi, Young Jae; Choi, Ji Yong; Choi, Young-Ung; Heo, Youn Seong; Choi, Cheol Young

    2016-10-01

    This study investigated the effects of increasing water temperature (22-30 °C) on the physiological stress response and immunity of goldfish, Carassius auratus, and the ability of green light-emitting diode (LED) irradiation or melatonin injections to mitigate this temperature-induced stress. To evaluate the effects of either green-wavelength LED light or melatonin on stress in goldfish, we measured plasma triiodothyronine (T3), thyroxine (T4), and thyroid hormone receptor (TR) mRNA expression; plasma cortisol and glucose; and immunoglobulin M (IgM) and lysozyme mRNA expression. The thyroid hormone activities, TR mRNA expression, and plasma cortisol and glucose were higher in goldfish exposed to high-temperature water, but were lower after exposure to melatonin or green-wavelength LED light. Lysozyme mRNA expression and plasma IgM activity and protein expression were lower after exposure to high water temperatures and higher after melatonin or green-wavelength LED light treatments. Therefore, high water temperature induced stress and decreased immunity; however, green-wavelength LED light and melatonin treatments mitigated the effects of stress and enhanced immunity. The benefits of melatonin decreased with time, whereas those of green-wavelength LED treatment did not.

  10. Effects of melatonin and green-wavelength LED light on the physiological stress and immunity of goldfish, Carassius auratus, exposed to high water temperature.

    PubMed

    Jung, Seo Jin; Kim, Na Na; Choi, Young Jae; Choi, Ji Yong; Choi, Young-Ung; Heo, Youn Seong; Choi, Cheol Young

    2016-10-01

    This study investigated the effects of increasing water temperature (22-30 °C) on the physiological stress response and immunity of goldfish, Carassius auratus, and the ability of green light-emitting diode (LED) irradiation or melatonin injections to mitigate this temperature-induced stress. To evaluate the effects of either green-wavelength LED light or melatonin on stress in goldfish, we measured plasma triiodothyronine (T3), thyroxine (T4), and thyroid hormone receptor (TR) mRNA expression; plasma cortisol and glucose; and immunoglobulin M (IgM) and lysozyme mRNA expression. The thyroid hormone activities, TR mRNA expression, and plasma cortisol and glucose were higher in goldfish exposed to high-temperature water, but were lower after exposure to melatonin or green-wavelength LED light. Lysozyme mRNA expression and plasma IgM activity and protein expression were lower after exposure to high water temperatures and higher after melatonin or green-wavelength LED light treatments. Therefore, high water temperature induced stress and decreased immunity; however, green-wavelength LED light and melatonin treatments mitigated the effects of stress and enhanced immunity. The benefits of melatonin decreased with time, whereas those of green-wavelength LED treatment did not. PMID:27012684

  11. Highly active oxygen reduction non-platinum group metal electrocatalyst without direct metal-nitrogen coordination

    NASA Astrophysics Data System (ADS)

    Strickland, Kara; Miner, Elise; Jia, Qingying; Tylus, Urszula; Ramaswamy, Nagappan; Liang, Wentao; Sougrati, Moulay-Tahar; Jaouen, Frédéric; Mukerjee, Sanjeev

    2015-06-01

    Replacement of noble metals in catalysts for cathodic oxygen reduction reaction with transition metals mostly create active sites based on a composite of nitrogen-coordinated transition metal in close concert with non-nitrogen-coordinated carbon-embedded metal atom clusters. Here we report a non-platinum group metal electrocatalyst with an active site devoid of any direct nitrogen coordination to iron that outperforms the benchmark platinum-based catalyst in alkaline media and is comparable to its best contemporaries in acidic media. In situ X-ray absorption spectroscopy in conjunction with ex situ microscopy clearly shows nitrided carbon fibres with embedded iron particles that are not directly involved in the oxygen reduction pathway. Instead, the reaction occurs primarily on the carbon-nitrogen structure in the outer skin of the nitrided carbon fibres. Implications include the potential of creating greater active site density and the potential elimination of any Fenton-type process involving exposed iron ions culminating in peroxide initiated free-radical formation.

  12. Highly active oxygen reduction non-platinum group metal electrocatalyst without direct metal-nitrogen coordination.

    PubMed

    Strickland, Kara; Miner, Elise; Jia, Qingying; Tylus, Urszula; Ramaswamy, Nagappan; Liang, Wentao; Sougrati, Moulay-Tahar; Jaouen, Frédéric; Mukerjee, Sanjeev

    2015-06-10

    Replacement of noble metals in catalysts for cathodic oxygen reduction reaction with transition metals mostly create active sites based on a composite of nitrogen-coordinated transition metal in close concert with non-nitrogen-coordinated carbon-embedded metal atom clusters. Here we report a non-platinum group metal electrocatalyst with an active site devoid of any direct nitrogen coordination to iron that outperforms the benchmark platinum-based catalyst in alkaline media and is comparable to its best contemporaries in acidic media. In situ X-ray absorption spectroscopy in conjunction with ex situ microscopy clearly shows nitrided carbon fibres with embedded iron particles that are not directly involved in the oxygen reduction pathway. Instead, the reaction occurs primarily on the carbon-nitrogen structure in the outer skin of the nitrided carbon fibres. Implications include the potential of creating greater active site density and the potential elimination of any Fenton-type process involving exposed iron ions culminating in peroxide initiated free-radical formation.

  13. Highly active oxygen reduction non-platinum group metal electrocatalyst without direct metal-nitrogen coordination.

    PubMed

    Strickland, Kara; Miner, Elise; Jia, Qingying; Tylus, Urszula; Ramaswamy, Nagappan; Liang, Wentao; Sougrati, Moulay-Tahar; Jaouen, Frédéric; Mukerjee, Sanjeev

    2015-01-01

    Replacement of noble metals in catalysts for cathodic oxygen reduction reaction with transition metals mostly create active sites based on a composite of nitrogen-coordinated transition metal in close concert with non-nitrogen-coordinated carbon-embedded metal atom clusters. Here we report a non-platinum group metal electrocatalyst with an active site devoid of any direct nitrogen coordination to iron that outperforms the benchmark platinum-based catalyst in alkaline media and is comparable to its best contemporaries in acidic media. In situ X-ray absorption spectroscopy in conjunction with ex situ microscopy clearly shows nitrided carbon fibres with embedded iron particles that are not directly involved in the oxygen reduction pathway. Instead, the reaction occurs primarily on the carbon-nitrogen structure in the outer skin of the nitrided carbon fibres. Implications include the potential of creating greater active site density and the potential elimination of any Fenton-type process involving exposed iron ions culminating in peroxide initiated free-radical formation. PMID:26059552

  14. Highly active oxygen reduction non-platinum group metal electrocatalyst without direct metal–nitrogen coordination

    PubMed Central

    Strickland, Kara; Miner, Elise; Jia, Qingying; Tylus, Urszula; Ramaswamy, Nagappan; Liang, Wentao; Sougrati, Moulay-Tahar; Jaouen, Frédéric; Mukerjee, Sanjeev

    2015-01-01

    Replacement of noble metals in catalysts for cathodic oxygen reduction reaction with transition metals mostly create active sites based on a composite of nitrogen-coordinated transition metal in close concert with non-nitrogen-coordinated carbon-embedded metal atom clusters. Here we report a non-platinum group metal electrocatalyst with an active site devoid of any direct nitrogen coordination to iron that outperforms the benchmark platinum-based catalyst in alkaline media and is comparable to its best contemporaries in acidic media. In situ X-ray absorption spectroscopy in conjunction with ex situ microscopy clearly shows nitrided carbon fibres with embedded iron particles that are not directly involved in the oxygen reduction pathway. Instead, the reaction occurs primarily on the carbon–nitrogen structure in the outer skin of the nitrided carbon fibres. Implications include the potential of creating greater active site density and the potential elimination of any Fenton-type process involving exposed iron ions culminating in peroxide initiated free-radical formation. PMID:26059552

  15. How well do blood folate concentrations predict dietary folate intakes in a sample of Canadian lactating women exposed to high levels of folate? An observational study

    PubMed Central

    Houghton, Lisa A; Sherwood, Kelly L; O'Connor, Deborah L

    2007-01-01

    Background In 1998, mandatory folic acid fortification of white flour and select cereal grain products was implemented in Canada with the intention to increase dietary folate intakes of reproducing women. Folic acid fortification has produced a dramatic increase in blood folate concentrations among reproductive age women, and a reduction in neural tube defect (NTD)-affected pregnancies. In response to improved blood folate concentrations, many health care professionals are asking whether a folic acid supplement is necessary for NTD prevention among women with high blood folate values, and how reliably high RBC folate concentrations predict folate intakes shown in randomized controlled trials to be protective against NTDs. The objective of this study was to determine how predictive blood folate concentrations and folate intakes are of each other in a sample of well-educated lactating Canadian women exposed to high levels of synthetic folate. Methods The relationship between blood folate concentrations and dietary folate intakes, determined by weighed food records, were assessed in a sample of predominantly university-educated lactating women (32 ± 4 yr) at 4-(n = 53) and 16-wk postpartum (n = 55). Results Median blood folate concentrations of all participants were well above plasma and RBC folate cut-off levels indicative of deficiency (6.7 and 317 nmol/L, respectively) and all, except for 2 subjects, were above the cut-off for NTD-risk reduction (>906 nmol/L). Only modest associations existed between total folate intakes and plasma (r = 0.46, P < 0.001) and RBC (r = 0.36, P < 0.01) folate concentrations at 16-wk postpartum. Plasma and RBC folate values at 16-wk postpartum correctly identified the quartile of folate intake of only 26 of 55 (47%) and 18 of 55 (33%) of subjects, respectively. The mean RBC folate concentration of women consuming 151–410 μg/d of synthetic folate (2nd quartile of intake) did not differ from that of women consuming >410 μg/d (3rd and

  16. Urinary arsenic metabolism in a Western Chinese population exposed to high-dose inorganic arsenic in drinking water: influence of ethnicity and genetic polymorphisms.

    PubMed

    Fu, Songbo; Wu, Jie; Li, Yuanyuan; Liu, Yan; Gao, Yanhui; Yao, Feifei; Qiu, Chuanying; Song, Li; Wu, Yu; Liao, Yongjian; Sun, Dianjun

    2014-01-01

    To investigate the differences in urinary arsenic metabolism patterns of individuals exposed to a high concentration of inorganic arsenic (iAs) in drinking water, an epidemiological investigation was conducted with 155 individuals living in a village where the arsenic concentration in the drinking water was 969μg/L. Blood and urine samples were collected from 66 individuals including 51 cases with skin lesions and 15 controls without skin lesions. The results showed that monomethylated arsenic (MMA), the percentage of MMA (%MMA) and the ratio of MMA to iAs (MMA/iAs) were significantly increased in patients with skin lesions as compared to controls, while dimethylated arsenic (DMA), the percentage of DMA (%DMA) and the ratio of DMA to MMA (DMA/MMA) were significantly reduced. The percent DMA of individuals with the Ala/Asp genotype of glutathione S-transferase omega 1 (GSTO1) was significantly lower than those with Ala/Ala. The percent MMA of individuals with the A2B/A2B genotype of arsenic (+3 oxidation state) methyltransferase (AS3MT) was significantly lower than those with AB/A2B. The iAs and total arsenic (tAs) content in the urine of a Tibetan population were significantly higher than that of Han and Hui ethnicities, whereas MMA/iAs was significantly lower than that of Han and Hui ethnicities. Our results showed that when exposed to the same arsenic environment, different individuals exhibited different urinary arsenic metabolism patterns. Gender and ethnicity affect these differences and above polymorphisms may be effectors too.

  17. Summary report of working group 3: High gradient and laser-structure based acceleration

    SciTech Connect

    Solyak, N.; Cowan, B.M.; /Tech-X, Boulder

    2010-01-01

    The charge for the working group on high gradient and laser-structure based acceleration was to assess the current challenges involved in developing an advanced accelerator based on electromagnetic structures, and survey state-of-the-art methods to address those challenges. The topics of more than 50 presentations in the working group covered a very broad range of issues, from ideas, theoretical models and simulations, to design and manufacturing of accelerating structures and, finally, experimental results on obtaining extremely high accelerating gradients in structures from conventional microwave frequency range up to THz and laser frequencies. Workshop discussion topics included advances in the understanding of the physics of breakdown and other phenomena, limiting high gradient performance of accelerating structures. New results presented in this workshop demonstrated significant progress in the fields of conventional vacuum structure-based acceleration, dielectric wakefield acceleration, and laser-structure acceleration.

  18. The high mobility group A1 gene: transforming inflammatory signals into cancer?

    PubMed

    Resar, Linda M S

    2010-01-15

    High mobility group A1 (HMGA1) is highly expressed during embryogenesis and in poorly differentiated cancers, and high levels portend a poor prognosis in some tumors. HMGA1 induces oncogenic transformation in cultured cells and causes aggressive cancers in transgenic mice, whereas blocking it interferes with transformation in experimental models. These findings suggest a pivotal role for HMGA1 in cancer. This review focuses on two recently described HMGA1 transcriptional targets that mediate inflammatory signals and drive malignant transformation because they could serve as biomarkers or therapeutic targets. Further elucidation of HMGA1 function in transformation promises to have a major impact on our war on cancer. PMID:20068164

  19. Effect of High Fructose and High Fat Diets on Pulmonary Sensitivity, Motor Activity, and Body Composition of Brown Norway Rats Exposed to Ozone

    EPA Science Inventory

    Diet-induced obesity has been suggested to lead to increased susceptibility to air pollutants such as ozone (03); however, there is little experimental evidence. Thirty day old male and female Brown Norway rats were fed a normal, high-fructose or high-fat diet for 12 weeks and th...

  20. Preference for High Status Predicts Implicit Outgroup Bias among Children from Low-Status Groups

    PubMed Central

    Newheiser, Anna-Kaisa; Dunham, Yarrow; Merrill, Anna; Hoosain, Leah; Olson, Kristina R.

    2014-01-01

    Whereas members of high-status racial groups show ingroup preference when attitudes are measured implicitly, members of low-status racial groups – both adults and children – typically show no bias, potentially reflecting awareness of the ingroup’s low status. We hypothesized that when status differences are especially pronounced, children from low-status groups would show an implicit outgroup bias, the strength of which might relate to attitudes toward status. We tested these predictions among 6–11-year-old Black and Coloured (i.e., multiracial) children from South Africa, a country marked by extreme status differentials among racial groups. As a measure of implicit intergroup bias, children (N=78) completed an Implicit Association Test, a speeded categorization task that assesses the relative strength of association between two target groups (in the present study, either Whites vs. Blacks or Whites vs. Coloureds) and positive versus negative evaluation. Children also completed explicit (i.e., self-report) measures of attitudes toward racial groups, as well as rich and poor people (a measure of attitudes toward status). Both groups of children showed an implicit outgroup-favoring (i.e., pro-White) bias, suggesting that children were sensitive to the extent of status differences. The only instance in which implicit pro-White bias did not emerge involved Black children’s evaluations of Whites versus Coloureds, both higher-status outgroups. Explicit preference for high status predicted implicit pro-White bias, particularly when the IAT contrasted two outgroups. The impact of status on the development of implicit and explicit intergroup bias is discussed. PMID:24219317

  1. University of Virginia High Energy Physics Group. Final performance report, June 1, 1989--January 31, 1994

    SciTech Connect

    1994-12-31

    The US Department of Energy Contracts for 1989 covered the initial year of the University of Virginia High Energy Physics Group. The first proposal was submitted in the fall of 1988 and the first allocation of funding was received in June 1989. This first contract which covered the time period June 1, 1989--January 31, 1990 was in the amount of $186,000 and covered UVa HEP group operations and equipment during that period. At that point, a regular contract year was established and two subsequent contracts were issued for February 1, 1990--January 31, 1991 and February 1, 1991--January 31, 992 with awards of $280,000 and $580,000, respectively. The funding between June, 1989 and January, 1992 covered the activities of both the UVa Theory Group (Task A) and the UVa HEP Experimental Group (Task B). Expenditures of all above funds was completed by January 31, 1994. In this time period, certain initial things were accomplished using the operating funds provided by DOE and the seed funds ($2.2 million over the period). There were three main areas of activities, the building of the University of Virginia HEP infrastructure (construction of lab space, computer facilities, electronic shop, machine shop and office space), the hiring of personnel (faculty, post docs, and students) and the physics activities of the group. Much of the physics program of the experimental group revolved around the study of production and decay of heavy flavor. A list of technical papers generated by their work is provided.

  2. Sex inequality, high transport costs, and exposed clinic location: reasons for loss to follow-up of clients under prevention of mother-to-child HIV transmission in eastern Uganda – a qualitative study

    PubMed Central

    Lubega, Muhamadi; Musenze, Ibrahim A; Joshua, Gukiina; Dhafa, George; Badaza, Rose; Bakwesegha, Christopher J; Reynolds, Steven J

    2013-01-01

    Background In Iganga, Uganda, 45% of women who tested HIV-positive during antenatal care between 2007 and 2010 were lost to follow-up (LTFU). We explored reasons for LTFU during prevention of mother-to-child transmission (PMTCT) from a client perspective in eastern Uganda, where antiretroviral therapy (ART) awareness is presumably high. Methods Seven key informant interviews and 20 in-depth interviews, including both clients who had been retained under PMTCT care and those LTFU during PMTCT were held. Ten focus-group discussions involving a total of 112 participants were also conducted with caretakers/ relatives of the PMTCT clients. Content analysis was performed to identify recurrent themes. Results Our findings indicate that LTFU during PMTCT in eastern Uganda was due to sex inequality, high transport costs to access the services, inadequate posttest counseling, lack of HIV status disclosure, and the isolated/exposed location of the ART clinic, which robs the clients of their privacy. Conclusion There is a need for approaches that empower women with social capital, knowledge, and skills to influence health-seeking practices. There is also a need to train low-ranking staff and take PMTCT services closer to the clients at the lower-level units to make them affordable and accessible to rural clients. Posttest counseling should be improved to enable PMTCT clients to appreciate the importance of PMTCT services through increasing the number of staff in antenatal care to match the client numbers for improved quality. The counseling should emphasize HIV status disclosure to partners and encourage partner escort for antenatal care visits for further counseling. The exposed and isolated ART clinic should be integrated with the other regular outpatient services to reduce the labeling stigma. PMID:23737663

  3. High mobility group B1 levels in sepsis and Disseminated Intravascular Coagulation.

    PubMed

    Eskici, Zeynep M; Açıkgöz, Şerefden; Pişkin, Nihal; Mungan, Görkem; Can, Murat; Güven, Berrak; Köktürk, Fürüzan

    2012-01-01

    Cytokines trigger coagulant and fibrinolytic systems in sepsis to result in Disseminated Intravascular Coagulation (DIC) that is an important complication and leads to disseminated hemorrhages and multi-organ failure. High Mobility Group B1 DNA Binding (HMGB1) protein is a cytokine taking part in systemic inflammatory response. The objective of this study was to investigate HMGB1 levels in groups of septic patients with and without DIC.Twenty-one septic patients without DIC and 12 septic patients with DIC from the Intensive Care Unit (ICU) were included in the study. In addition, 20 patients admitted to the ICU without sepsis or DIC and 20 healthy volunteers served as controls. Levels of HMGB1, prothrombin time, activated partial thromboplastin time, fibrinogen, D-dimer, protein C, protein S, anti-thrombin III (ATIII), platelet (thrombocyte) and leukocyte count were determined. Levels of fibrinogen, protein C, ATIII and platelet count were significantly lower and D-dimer was significantly higher in the group with sepsis plus DIC compared to the group with sepsis without DIC. Levels of HMGB1 were higher in the group with sepsis and DIC compared to the group with sepsis; however, the difference was not statistically significant and the levels of HGMB1 of both groups were significantly higher compared to ICU and healthy control groups. HMGB1 levels were not significantly different in survivor and non survivor patients. HMGB1 levels did not differ in lower respiratory tract infection (LRTI) and urinary tract infection (UTI) in regard to the etiology of sepsis.

  4. Cell membrane fatty acid changes and desaturase expression of Saccharomyces bayanus exposed to high pressure homogenization in relation to the supplementation of exogenous unsaturated fatty acids

    PubMed Central

    Serrazanetti, Diana I.; Patrignani, Francesca; Russo, Alessandra; Vannini, Lucia; Siroli, Lorenzo; Gardini, Fausto; Lanciotti, Rosalba

    2015-01-01

    Aims: The aim of this work was to study the responses of Saccharomyces bayanus cells exposed to sub-lethal high-pressure homogenization (HPH) and determine whether the plasmatic membrane can sense HPH in the presence, or absence, of exogenous unsaturated fatty acids (UFAs) in the growth medium. Methods and Results: High-pressure homogenization damaged and caused the collapse of cell walls and membranes of a portion of cells; however, HPH did not significantly affect S. bayanus cell viability (less than 0.3 Log CFU ml-1). HPH strongly affected the membrane fatty acid (FA) composition by increasing the percentage of total UFA when compared with saturated fatty acids. The gene expression showed that the transcription of OLE1, ERG3, and ERG11 increased after HPH. The presence of exogenous UFA abolished HPH-induced effects on the OLE1 and ERG3 genes, increased the percentage of membrane lipids and decreased the expression of OLE1 and ERG3 within 30 min of treatment. Conclusion: The results suggest a key role for UFA in the microbial cell response to sub-lethal stress. In addition, these data provide insight into the molecular basis of the response of S. bayanus to this innovative technology. Significance and Impact of the Study: Elucidation of the mechanism of action for sub-lethal HPH will enable the utilization of this technology to modulate the starter performance at the industrial scale. PMID:26528258

  5. Group velocity locked vector dissipative solitons in a high repetition rate fiber laser.

    PubMed

    Luo, Yiyang; Li, Lei; Liu, Deming; Sun, Qizhen; Wu, Zhichao; Xu, Zhilin; Tang, Dingyuan; Fu, Songnian; Zhao, Luming

    2016-08-01

    Vectorial nature of dissipative solitons (DSs) with high repetition rate is studied for the first time in a normal-dispersion fiber laser. Despite the fact that the formed DSs are strongly chirped and the repetition rate is greater than 100 MHz, polarization locked and polarization rotating group velocity locked vector DSs can be formed under 129.3 MHz fundamental mode-locking and 258.6 MHz harmonic mode-locking of the fiber laser, respectively. The two orthogonally polarized components of these vector DSs possess distinctly different central wavelengths and travel together at the same group velocity in the laser cavity, resulting in a gradual spectral edge and small steps on the optical spectrum, which can be considered as an auxiliary indicator of the group velocity locked vector DSs. Moreover, numerical simulations well confirm the experimental observations and further reveal the impact of the net cavity birefringence on the properties of the formed vector DSs. PMID:27505834

  6. Soluble Thrombomodulin Ameliorates Ischemia-Reperfusion Injury of Liver Grafts by Modulating the Proinflammatory Role of High-Mobility Group Box 1.

    PubMed

    Kashiwadate, Toshiaki; Miyagi, Shigehito; Hara, Yasuyuki; Akamatsu, Yorihiro; Sekiguchi, Satoshi; Kawagishi, Naoki; Ohuchi, Noriaki; Satomi, Susumu

    2016-01-01

    Transplantation using grafts obtained after cardiac death (CD) is considered a promising solution for graft shortages. However, no standard criteria for organ preservation have been established for CD donors. High-mobility group box 1 (HMGB1) is a DNA-binding protein that is released from dying hepatocytes as an early mediator of inflammation and organ tissue damage. HMGB1 stimulates immunocytes to produce inflammatory cytokines, thereby amplifying the inflammatory response. Thrombomodulin is an integral membrane protein that functions as an endothelial anticoagulant cofactor, and it binds HMGB1 through the extracellular domain. We investigated the effects of ART-123, recombinant human soluble thrombomodulin, on warm ischemia-reperfusion injury in liver grafts. Male Wistar rats were divided into four ex vivo groups: heart-beating (HB) group, in which livers were isolated from HB donors; CD group, in which livers were isolated from CD donors exposed to apnea-induced conditions and warm ischemic conditions for 30 min after cardiac arrest; and two CD groups pretreated with ART-123 (1 or 5 mg/kg). Each isolated liver was reperfused for 1 h after cold preservation for 6 h. The perfusate levels of HMGB1, LDH, TNF-α, and IL-6 were significantly lower in the CD group pretreated with ART-123 (5 mg/kg) than in the CD group. Bile production was significantly higher in the CD group pretreated with ART-123 (5 mg/kg) than in the CD group. The sinusoidal spaces were significantly narrower in the CD group than in the other groups. We propose that ART-123 maintains sinusoidal microcirculation by reducing endothelial cell damage during warm ischemia-reperfusion injury. PMID:27523810

  7. Urinary arsenic metabolism in a Western Chinese population exposed to high-dose inorganic arsenic in drinking water: Influence of ethnicity and genetic polymorphisms

    SciTech Connect

    Fu, Songbo; Wu, Jie; Li, Yuanyuan; Liu, Yan; Gao, Yanhui; Yao, Feifei; Qiu, Chuanying; Song, Li; Wu, Yu; Liao, Yongjian; Sun, Dianjun

    2014-01-01

    To investigate the differences in urinary arsenic metabolism patterns of individuals exposed to a high concentration of inorganic arsenic (iAs) in drinking water, an epidemiological investigation was conducted with 155 individuals living in a village where the arsenic concentration in the drinking water was 969 μg/L. Blood and urine samples were collected from 66 individuals including 51 cases with skin lesions and 15 controls without skin lesions. The results showed that monomethylated arsenic (MMA), the percentage of MMA (%MMA) and the ratio of MMA to iAs (MMA/iAs) were significantly increased in patients with skin lesions as compared to controls, while dimethylated arsenic (DMA), the percentage of DMA (%DMA) and the ratio of DMA to MMA (DMA/MMA) were significantly reduced. The percent DMA of individuals with the Ala/Asp genotype of glutathione S-transferase omega 1 (GSTO1) was significantly lower than those with Ala/Ala. The percent MMA of individuals with the A2B/A2B genotype of arsenic (+ 3 oxidation state) methyltransferase (AS3MT) was significantly lower than those with AB/A2B. The iAs and total arsenic (tAs) content in the urine of a Tibetan population were significantly higher than that of Han and Hui ethnicities, whereas MMA/iAs was significantly lower than that of Han and Hui ethnicities. Our results showed that when exposed to the same arsenic environment, different individuals exhibited different urinary arsenic metabolism patterns. Gender and ethnicity affect these differences and above polymorphisms may be effectors too. - Highlights: • We first survey a village with high iAs content in the drinking water (969 μg/L). • 90 villagers suffered typical skin lesions with a morbidity rate of 58%. • Cases exhibited higher %MMA and MMA/iAs, and lower %DMA and DMA/MMA than controls. • Gender and ethnicity affect the differences of iAs methylation metabolism levels. • GSTO1 and AS3MT gene polymorphisms may be factors too.

  8. High-Resolution Group Quantization Phase Processing Method in Radio Frequency Measurement Range.

    PubMed

    Du, Baoqing; Feng, Dazheng; Tang, Yaohua; Geng, Xin; Zhang, Duo; Cai, Chaofeng; Wan, Maoquan; Yang, Zhigang

    2016-01-01

    Aiming at the more complex frequency translation, the longer response time and the limited measurement precision in the traditional phase processing, a high-resolution phase processing method by group quantization higher than 100 fs level is proposed in radio frequency measurement range. First, the phase quantization is used as a step value to quantize every phase difference in a group by using the fixed phase relationships between different frequencies signals. The group quantization is formed by the results of the quantized phase difference. In the light of frequency drift mainly caused by phase noise of measurement device, a regular phase shift of the group quantization is produced, which results in the phase coincidence of two comparing signals which obtain high-resolution measurement. Second, in order to achieve the best coincidences pulse, a subtle delay is initiatively used to reduce the width of the coincidences fuzzy area according to the transmission characteristics of the coincidences in the specific medium. Third, a series of feature coincidences pulses of fuzzy area can be captured by logic gate to achieve the best phase coincidences information for the improvement of the measurement precision. The method provides a novel way to precise time and frequency measurement. PMID:27388587

  9. High-Resolution Group Quantization Phase Processing Method in Radio Frequency Measurement Range

    PubMed Central

    Du, Baoqing; Feng, Dazheng; Tang, Yaohua; Geng, Xin; Zhang, Duo; Cai, Chaofeng; Wan, Maoquan; Yang, Zhigang

    2016-01-01

    Aiming at the more complex frequency translation, the longer response time and the limited measurement precision in the traditional phase processing, a high-resolution phase processing method by group quantization higher than 100 fs level is proposed in radio frequency measurement range. First, the phase quantization is used as a step value to quantize every phase difference in a group by using the fixed phase relationships between different frequencies signals. The group quantization is formed by the results of the quantized phase difference. In the light of frequency drift mainly caused by phase noise of measurement device, a regular phase shift of the group quantization is produced, which results in the phase coincidence of two comparing signals which obtain high-resolution measurement. Second, in order to achieve the best coincidences pulse, a subtle delay is initiatively used to reduce the width of the coincidences fuzzy area according to the transmission characteristics of the coincidences in the specific medium. Third, a series of feature coincidences pulses of fuzzy area can be captured by logic gate to achieve the best phase coincidences information for the improvement of the measurement precision. The method provides a novel way to precise time and frequency measurement. PMID:27388587

  10. High-Resolution Group Quantization Phase Processing Method in Radio Frequency Measurement Range.

    PubMed

    Du, Baoqing; Feng, Dazheng; Tang, Yaohua; Geng, Xin; Zhang, Duo; Cai, Chaofeng; Wan, Maoquan; Yang, Zhigang

    2016-07-08

    Aiming at the more complex frequency translation, the longer response time and the limited measurement precision in the traditional phase processing, a high-resolution phase processing method by group quantization higher than 100 fs level is proposed in radio frequency measurement range. First, the phase quantization is used as a step value to quantize every phase difference in a group by using the fixed phase relationships between different frequencies signals. The group quantization is formed by the results of the quantized phase difference. In the light of frequency drift mainly caused by phase noise of measurement device, a regular phase shift of the group quantization is produced, which results in the phase coincidence of two comparing signals which obtain high-resolution measurement. Second, in order to achieve the best coincidences pulse, a subtle delay is initiatively used to reduce the width of the coincidences fuzzy area according to the transmission characteristics of the coincidences in the specific medium. Third, a series of feature coincidences pulses of fuzzy area can be captured by logic gate to achieve the best phase coincidences information for the improvement of the measurement precision. The method provides a novel way to precise time and frequency measurement.

  11. High-Resolution Group Quantization Phase Processing Method in Radio Frequency Measurement Range

    NASA Astrophysics Data System (ADS)

    Du, Baoqing; Feng, Dazheng; Tang, Yaohua; Geng, Xin; Zhang, Duo; Cai, Chaofeng; Wan, Maoquan; Yang, Zhigang

    2016-07-01

    Aiming at the more complex frequency translation, the longer response time and the limited measurement precision in the traditional phase processing, a high-resolution phase processing method by group quantization higher than 100 fs level is proposed in radio frequency measurement range. First, the phase quantization is used as a step value to quantize every phase difference in a group by using the fixed phase relationships between different frequencies signals. The group quantization is formed by the results of the quantized phase difference. In the light of frequency drift mainly caused by phase noise of measurement device, a regular phase shift of the group quantization is produced, which results in the phase coincidence of two comparing signals which obtain high-resolution measurement. Second, in order to achieve the best coincidences pulse, a subtle delay is initiatively used to reduce the width of the coincidences fuzzy area according to the transmission characteristics of the coincidences in the specific medium. Third, a series of feature coincidences pulses of fuzzy area can be captured by logic gate to achieve the best phase coincidences information for the improvement of the measurement precision. The method provides a novel way to precise time and frequency measurement.

  12. The effect of individual or group guidelines on the calibration accuracy of high school biology students

    NASA Astrophysics Data System (ADS)

    Walck, Camilla C.

    The effect of individual or group guidelines on the calibration accuracy of high school biology students was investigated. The study was conducted with 102 International Baccalaureate Middle Years Program biology students in a public school setting. The study was carried out over three testing occasions. Students worked in group or individual settings with and without calibration guidelines. Four intact classes were randomly assigned to one of four conditions: groups calibrating without guidelines; groups calibrating with guidelines; individuals calibrating without guidelines; individuals calibrating with guidelines. The students participated in the calibration activities one block before they actually took each of the three tests. On the day of each test, immediately before taking the test, each student made predictions as to what they thought they would score on the test. Immediately after taking the test each student made postdictions on what they thought they scored on the test. Calibration accuracy was determined by calculating the difference between prediction and postdiction scores and the actual test score achieved. The results indicated that students who calibrated in groups showed trends of more accurate calibration predictions. Although one testing intervention showed significant results for postdiction accuracy, the other two testing interventions showed varied results. Students who calibrated in groups achieved higher scores on tests than did students who calibrated individually. In addition, guidelines were shown to be a significant factor in increasing achievement for students who calibrated individually. For students calibrating in groups guidelines had little impact. The results support the need for more research in metacognition and calibration techniques in order to improve student academic success.

  13. Chronic bronchitis is an independently associated factor for more symptom and high-risk groups

    PubMed Central

    Choi, Joon Young; Yoon, Hyoung Kyu; Park, Seoung Ju; Park, Yong Bum; Shin, Kyeong-Cheol; Na, Ju Ock; Yoo, Kwang Ha; Jung, Ki-Suck; Kim, Young Kyoon; Rhee, Chin Kook

    2016-01-01

    Background The chronic bronchitis (CB) phenotype has been associated with poor quality of life and an increased risk of disease in patients with COPD. However, little information exists regarding the relationship between the CB phenotype and the COPD assessment test (CAT) score. The goal of this study was to reveal the different pattern of CAT scores between CB and non-CB patients. Moreover, we aimed to investigate whether the CB phenotype is an independently associated factor for more symptom and high-risk groups. Methods Data were obtained from the Korea COPD Subgroup Study cohort recruited from 46 centers in South Korea since April 2012. CB patients were defined as having a chronic cough and sputum for 3 months per year, for a period of 2 consecutive years. We investigated the pattern of CAT and subquestionnaire scores between CB and non-CB patients. We also analyzed the proportion of CB phenotypes in each Global initiative for chronic Obstructive Lung Disease (GOLD) stage. Finally, we performed a logistic regression analysis to identify whether the CB phenotype was an independently associated factor for more symptom and high-risk groups. Results Of the 1,106 study patients, 11.5% of patients were found to have a CB phenotype. CB phenotypes were most common in GOLD III (GOLD 2006) and GOLD D (GOLD 2015) stages. CAT scores were significantly higher in CB patients not only in terms of the total score but also for each subquestionnaire. Logistic regression revealed that the CB phenotype is an independently associated factor for more symptom and high-risk groups. Conclusion The present study revealed that CB patients have higher CAT scores and subquestionnaire results compared to non-CB patients. Additionally, we demonstrated that the CB phenotype is an independently associated factor for both more symptom and high-risk groups. PMID:27382269

  14. Calculation of intensity of high energy muon groups observed deep underground

    NASA Technical Reports Server (NTRS)

    Vavilov, Y. N.; Dedenko, L. G.

    1985-01-01

    The intensity of narrow muon groups observed in Kolar Gold Field (KGF) at the depth of 3375 m.w.e. was calculated in terms of quark-gluon strings model for high energy hadron - air nuclei interactions by the method of direct modeling of nuclear cascade in the air and muon propagation in the ground for normal primary cosmic ray composition. The calculated intensity has been found to be approx. 10 to the 4 times less than one observed experimentally.

  15. The space shuttle payload planning working groups. Volume 3: High energy astrophysics

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The findings of the High Energy Astrophysics working group of the space shuttle payload planning activity are presented. The objectives to be accomplished during space shuttle missions are defined as: (1) X-ray astronomy, (2) hard X-ray and gamma ray astronomy, and (3) cosmic ray astronomy. The instruments and test equipment required to accomplish the mission are identified. Recommendations for managing the installation of the equipment and conducting the missions are included.

  16. Culturable microbial groups and thallium-tolerant fungi in soils with high thallium contamination.

    PubMed

    Sun, Jialong; Zou, Xiao; Ning, Zengping; Sun, Min; Peng, Jingquan; Xiao, Tangfu

    2012-12-15

    Thallium (Tl) contamination in soil exerts a significant threat to the ecosystem health due to its high toxicity. However, little is known about the effect of Tl on the microbial community in soil. The present study aimed at characterizing the culturable microbial groups in soils which experience for a long time high Tl contamination and elevated Hg and As. The contamination originates from As, Hg and Tl sulfide mineralization and the associated mining activities in the Guizhou Province, Southwest China. Our investigation showed the existence of culturable bacteria, filamentous fungi and actinomyces in long-term Tl-contaminated soils. Some fungal groups grow in the presence of high Tl level up to 1000 mg kg⁻¹. We have isolated and identified nine Tl-tolerant fungal strains based on the morphological traits and ITS analysis. The dominant genera identified were Trichoderma, Penicillium and Paecilomyces. Preliminary data obtained in this study suggested that certain microbes were able to face high Tl pollution in soil and maintain their metabolic activities and resistances. The highly Tl-tolerant fungi that we have isolated are potentially useful in the remediation of Tl-contaminated sites.

  17. Deuterium occupation of vacancy-type defects in argon-damaged tungsten exposed to high flux and low energy deuterium plasma

    NASA Astrophysics Data System (ADS)

    Zhu, Xiu-Li; Zhang, Ying; Cheng, Long; Yuan, Yue; De Temmerman, Gregory; Wang, Bao-Yi; Cao, Xing-Zhong; Lu, Guang-Hong

    2016-03-01

    Doppler broadening spectroscopy in the positron annihilation technique (DBS-PA) has been employed to investigate the defect properties in argon-damaged tungsten exposed to low-energy and high flux deuterium plasma. Argon ion irradiations with energy 500 keV are performed for tungsten samples with various levels of damage. The remarkable increment of the S parameter in DBS-PA indicates the introduction of vacancy-type defects in argon irradiated tungsten. An increase of ion fluence results in a continuous increase of the S parameter until saturation. Unexpectedly, a much higher fluence leads to a decrease of the S parameter in the near surface, and the (S,W) slope changes greatly. This should be associated with the formation of argon-vacancy complexes in the near surface produced by the excessive implanted argon ions. With deuterium plasma exposure, a significant decrease of the S parameter occurs in the pre-irradiated tungsten, suggesting the sharp reduction of the number and density of the vacancy-type defects. The thermal desorption spectroscopy results demonstrate that the argon-damaged tungsten, compared to the pristine one, exhibits an enhanced low-temperature desorption peak and an additional and broad high-temperature desorption peak, which indicates that deuterium atoms are trapped in both low-energy and high-energy sites. All these observations directly indicate the deuterium occupation of irradiation-induced vacancy defects in damaged tungsten, which is responsible for the remarkable increase of the deuterium retention in comparison with the pristine one.

  18. Infection Risk for Persons Exposed to Highly Pathogenic Avian Influenza A H5 Virus–Infected Birds, United States, December 2014–March 2015

    PubMed Central

    Nelson, Deborah I.; Deliberto, Thomas J.; Blanton, Lenee; Kniss, Krista; Levine, Min Z.; Trock, Susan C.; Finelli, Lyn; Jhung, Michael A.

    2015-01-01

    Newly emerged highly pathogenic avian influenza (HPAI) A H5 viruses have caused outbreaks among birds in the United States. These viruses differ genetically from HPAI H5 viruses that previously caused human illness, most notably in Asia and Africa. To assess the risk for animal-to-human HPAI H5 virus transmission in the United States, we determined the number of persons with self-reported exposure to infected birds, the number with an acute respiratory infection (ARI) during a 10-day postexposure period, and the number with ARI who tested positive for influenza by real-time reverse transcription PCR or serologic testing for each outbreak during December 15, 2014–March 31, 2015. During 60 outbreaks in 13 states, a total of 164 persons were exposed to infected birds. ARI developed in 5 of these persons within 10 days of exposure. H5 influenza virus infection was not identified in any persons with ARI, suggesting a low risk for animal-to-human HPAI H5 virus transmission. PMID:26583382

  19. Protein kinase A-Iα regulates Na,K-ATPase endocytosis in alveolar epithelial cells exposed to high CO(2) concentrations.

    PubMed

    Lecuona, Emilia; Sun, Haiying; Chen, Jiwang; Trejo, Humberto E; Baker, Margaret A; Sznajder, Jacob I

    2013-05-01

    Elevated concentrations of CO2 (hypercapnia) lead to alveolar epithelial dysfunction by promoting Na,K-ATPase endocytosis. In the present report, we investigated whether the CO2/HCO3(-) activated soluble adenylyl cyclase (sAC) regulates this process. We found that hypercapnia increased the production of cyclic adenosine monophosphate (cAMP) and stimulated protein kinase A (PKA) activity via sAC, which was necessary for Na,K-ATPase endocytosis. During hypercapnia, cAMP was mainly produced in specific microdomains in the proximity of the plasma membrane, leading to PKA Type Iα activation. In alveolar epithelial cells exposed to high CO2 concentrations, PKA Type Iα regulated the time-dependent phosphorylation of the actin cytoskeleton component α-adducin at serine 726. Cells expressing small hairpin RNA for PKAc, dominant-negative PKA Type Iα, small interfering RNA for α-adducin, and α-adducin with serine 726 mutated to alanine prevented Na,K-ATPase endocytosis. In conclusion, we provide evidence for a new mechanism by which hypercapnia via sAC, cAMP, PKA Type Iα, and α-adducin regulates Na,K-ATPase endocytosis in alveolar epithelial cells. PMID:23349050

  20. Infection Risk for Persons Exposed to Highly Pathogenic Avian Influenza A H5 Virus-Infected Birds, United States, December 2014-March 2015.

    PubMed

    Arriola, Carmen S; Nelson, Deborah I; Deliberto, Thomas J; Blanton, Lenee; Kniss, Krista; Levine, Min Z; Trock, Susan C; Finelli, Lyn; Jhung, Michael A

    2015-12-01

    Newly emerged highly pathogenic avian influenza (HPAI) A H5 viruses have caused outbreaks among birds in the United States. These viruses differ genetically from HPAI H5 viruses that previously caused human illness, most notably in Asia and Africa. To assess the risk for animal-to-human HPAI H5 virus transmission in the United States, we determined the number of persons with self-reported exposure to infected birds, the number with an acute respiratory infection (ARI) during a 10-day postexposure period, and the number with ARI who tested positive for influenza by real-time reverse transcription PCR or serologic testing for each outbreak during December 15, 2014-March 31, 2015. During 60 outbreaks in 13 states, a total of 164 persons were exposed to infected birds. ARI developed in 5 of these persons within 10 days of exposure. H5 influenza virus infection was not identified in any persons with ARI, suggesting a low risk for animal-to-human HPAI H5 virus transmission.

  1. Influence of temperature-dependent thermal parameters on temperature elevation of tissue exposed to high-intensity focused ultrasound: numerical simulation.

    PubMed

    Guntur, Sitaramanjaneya Reddy; Choi, Min Joo

    2015-03-01

    High-intensity focused ultrasound (HIFU) has been used successfully as a non-invasive modality in treating solid tumors. The temperature rise HIFU irradiation causes in a tissue depends on the thermal properties of the tissue. This study was motivated by our observation that the thermal properties of a tissue vary significantly with temperature (Guntur SR, Lee KI, Paeng DG, Coleman AJ, Choi MJ. Ultrasound Med Biol 2013;39:1771-1784). This research investigated how significantly the alteration of tissue thermal parameters, in the ranges of values measured at 25°C-90°C, affects prediction of the temperature elevation of tissue under the same HIFU exposure. The numerical simulation was performed by coupling a non-linear Khokhlov-Zabolotskaya-Kuznetsov equation with a bio-heat transfer function. In the conventional method of prediction, the thermal parameters were set as constants measured at room temperature (25°C). This study compared the conventional prediction with those predicted with different thermal parameters measured at the various temperatures up to 90°C. The results indicated that the conventional method significantly overestimated the rise in focal temperature in the liver tissue exposed to a clinical HIFU field, compared with the prediction made using thermal parameters measured at temperatures that cause thermal denaturation. This finding suggests that temperature-dependent thermal parameters should be considered in predicting the temperature rise in a tissue to avoid use of an insufficient thermal dose in treatment planning for HIFU surgery.

  2. Infection Risk for Persons Exposed to Highly Pathogenic Avian Influenza A H5 Virus-Infected Birds, United States, December 2014-March 2015.

    PubMed

    Arriola, Carmen S; Nelson, Deborah I; Deliberto, Thomas J; Blanton, Lenee; Kniss, Krista; Levine, Min Z; Trock, Susan C; Finelli, Lyn; Jhung, Michael A

    2015-12-01

    Newly emerged highly pathogenic avian influenza (HPAI) A H5 viruses have caused outbreaks among birds in the United States. These viruses differ genetically from HPAI H5 viruses that previously caused human illness, most notably in Asia and Africa. To assess the risk for animal-to-human HPAI H5 virus transmission in the United States, we determined the number of persons with self-reported exposure to infected birds, the number with an acute respiratory infection (ARI) during a 10-day postexposure period, and the number with ARI who tested positive for influenza by real-time reverse transcription PCR or serologic testing for each outbreak during December 15, 2014-March 31, 2015. During 60 outbreaks in 13 states, a total of 164 persons were exposed to infected birds. ARI developed in 5 of these persons within 10 days of exposure. H5 influenza virus infection was not identified in any persons with ARI, suggesting a low risk for animal-to-human HPAI H5 virus transmission. PMID:26583382

  3. Super-high photocatalytic activity of Fe2O3 nanoparticles anchored on Bi2O2CO3 nanosheets with exposed {0 0 1} active facets

    NASA Astrophysics Data System (ADS)

    Hu, Dandan; Zhang, Kaiyou; Yang, Qi; Wang, Mingjun; Xi, Yi; Hu, Chenguo

    2014-10-01

    Structure engineering enables us to design novel photocatalysts with high efficiency and stability. Here visible light absorbing Fe2O3 semiconductor is chosen as sensitizer to modify wide band-gap Bi2O2CO3 semiconductor in order to enhance its photocatalytic properties by shifting the UV-driven catalytic activity to visible-light-driven catalytic activity. The Bi2O2CO3@Fe2O3 nanosheets with exposed active {0 0 1} facet were fabricated by a facile one-step modified hydrothermal method. The thermal stability, crystal structure, morphology and optical band gap were characterized. The photocatalytic activities of the Bi2O2CO3 and Bi2O2CO3@Fe2O3 with different molar ratio of Fe2O3 to Bi2O2CO3 were compared. It was found that the Bi2O2CO3@Fe2O3 catalyst can degrade rhodamine-B within 25 min under the simulated sunlight, displaying greatly enhanced photocatalytic activity with respect to the Bi2O2CO3 catalyst. The photocatalyst showed good photostability and recyclability. A mixture of multi-colored dyes including rhodamine-B, methylene blue and methyl orange can be completely degraded by the Bi2O2CO3@Fe2O3 catalyst (5 mol% Fe2O3) within 45 min under the simulated sunlight irradiation. The photocatalytic mechanism was discussed in detail.

  4. Ethyl pyruvate attenuates murine allergic rhinitis partly by decreasing high mobility group box 1 release

    PubMed Central

    Chen, Shan; Wang, Yanjun; Gong, Guoqing; Chen, Jianjun; Niu, Yongzhi

    2015-01-01

    High-mobility group box 1 (HMGB1) protein, a pro-inflammatory DNA-binding protein, meditates inflammatory responses through Toll-like receptor-4 signals and amplifies allergic inflammation by interacting with the receptor for advanced glycation end products. Previous studies have shown that HMGB1 is elevated in the nasal lavage fluids (NLF) of children suffering from allergic rhinitis (AR) and is associated with the severity of this disease. Furthermore, HMGB1 has been implicated in the pathogenesis of lower airway allergic diseases, such as asthma. Ethyl pyruvate (EP) has proven to be an effective anti-inflammatory agent for numerous airway diseases. Moreover, EP can inhibit the secretion of HMGB1. However, few studies have examined the effect of EP on AR. We hypothesized that HMGB1 plays an important role in the pathogenesis of AR and studied it using an AR mouse model. Forty BALB/c mice were divided into four groups: the control group, AR group, 50 mg/kg EP group, and 100 mg/kg EP group. The mice in the AR and EP administration groups received ovalbumin (OVA) sensitization and challenge, whereas those in the control group were given sterile saline instead of OVA. The mice in the EP administration group were given an intraperitoneal injection of EP 30 min before each OVA treatment. The number of nasal rubbings and sneezes of each mouse was counted after final treatment. Hematoxylin–eosin staining, AB-PAS staining, interleukin-4 and 13 in NLF, IgE, and the protein expression of HMGB1 were measured. Various features of the allergic inflammation after OVA exposure, including airway eosinophilia, Th-2 cytokine production, total IgE, and goblet cell hyperplasia were significantly inhibited by treatment with EP and the expression and release of HMGB1 were reduced after EP administration in a dose-dependent manner. These results indicate that HMGB1 is a potential therapeutic target of AR and that EP attenuates AR by decreasing HMGB1 expression. PMID:25681468

  5. Update: cohort mortality study of workers highly exposed to polychlorinated biphenyls (PCBs) during the manufacture of electrical capacitors, 1940-1998

    PubMed Central

    Prince, Mary M; Hein, Misty J; Ruder, Avima M; Waters, Martha A; Laber, Patricia A; Whelan, Elizabeth A

    2006-01-01

    Background The National Institute for Occupational Safety and Health previously reported mortality for a cohort of workers considered highly exposed to polychlorinated biphenyls (PCBs) between 1939 and 1977 at two electrical capacitor manufacturing plants. The current study updated vital status, examined liver and rectal cancer mortality previously reported in excess in this cohort and evaluated mortality from non-Hodgkin's lymphoma (NHL) and cancers of the stomach, intestine, breast, prostate, skin (melanoma) and brain reported to be in excess in other cohort and case-control studies of PCB-exposed persons. Methods Mortality was updated through 1998 for 2572 workers. Age-, gender-, race- and calendar year-adjusted standardized mortality ratios (SMRs) and 95% confidence intervals (CI) were calculated using U.S., state and county referent rates. SMRs using U.S. referent rates are reported. Duration of employment was used as a surrogate for exposure. Results Consistent with the previous follow-up, mortality from biliary passage, liver and gall bladder cancer was significantly elevated (11 deaths, SMR 2.11, CI 1.05 – 3.77), but mortality from rectal cancer was not (6 deaths, SMR 1.47, CI 0.54 – 3.21). Among women, mortality from intestinal cancer (24 deaths, SMR 1.89, CI 1.21 – 2.82) and from "other diseases of the nervous system and sense organs", which include Parkinson's disease and amyotrophic lateral sclerosis, (15 deaths, SMR 2.07, CI 1.16 – 3.42) were elevated. There were four ALS deaths, all women (SMR 4.35, CI 1.19–11.14). Mortality was elevated for myeloma (7 deaths, SMR 2.11, CI 0.84 – 4.34), particularly among workers employed 10 years or more (5 deaths, SMR 2.80, CI 0.91 – 6.54). No linear associations between mortality and duration of employment were observed for the cancers of interest. Conclusion This update found that the earlier reported excess in this cohort for biliary, liver and gall bladder cancer persisted with longer follow

  6. Report of the Snowmass M6 Working Group on high intensity proton sources

    SciTech Connect

    Weiren Chou and J. Wei

    2002-08-20

    The U.S. high-energy physics program needs an intense proton source, a 1-4 MW Proton Driver (PD), by the end of this decade. This machine will serve as a stand-alone facility that will provide neutrino superbeams and other high intensity secondary beams such as kaons, muons, neutrons, and anti-protons (cf. E1 and E5 group reports) and also serve as the first stage of a neutrino factory (cf. M1 group report). It can also be a high brightness source for a VLHC. Based on present accelerator technology and project construction experience, it is both feasible and cost-effective to construct a 1-4 MW Proton Driver. Two recent PD design studies have been made, one at FNAL and the other at the BNL. Both designed PD's for 1 MW proton beams at a cost of about U.S. $200M (excluding contingency and overhead) and both designs were upgradeable to 4 MW. An international collaboration between FNAL, BNL and KEK on high intensity proton facilities is addressing a number of key design issues. The superconducting (sc) RF cavities, cryogenics, and RF controls developed for the SNS can be directly adopted to save R&D efforts, cost, and schedule. PD studies are also actively being pursued at Europe and Japan.

  7. Closeout Report: Experimental High Energy Physics Group at the University of South Alabama

    SciTech Connect

    Jenkins, Charles M; Godang, Romulus

    2013-06-25

    The High Energy Physics group at the University of South Alabama has been supported by this research grant (DE-FG02-96ER40970) since 1996. One researcher, Dr. Merrill Jenkins, has been supported on this grant during this time worked on fixed target experiments at the Fermi National Accelerator Laboratory, west of Chicago, Illinois. These experiments have been E-705, E-771, E-871 (HyperCP) and E-921 (CKM) before it was canceled for budgetary reasons. After the cancellation of CKM, Dr. Jenkins joined the Compact Muon Solenoid (CMS) experiment as an associate member via the High Energy Physics Group at the Florida State University. A second, recently tenured faculty member, Dr. Romulus Godang joined the group in 2009 and has been supported by this grant since then. Dr. Godang is working on the BaBaR experiment at SLAC and has joined the Belle-II experiment located in Japan at KEK. According to the instructions sent to us by our grant monitor, we are to concentrate on the activities over the last three years in this closeout report.

  8. Report of the Snowmass T7 working group on high performance computing

    SciTech Connect

    K. Ko; R. Ryne; P. Spentzouris

    2002-12-05

    The T7 Working Group on High Performance Computing (HPC) had more than 30 participants. During the three weeks at Snowmass there were about 30 presentations. This working group also had joint sessions with a number of other working groups, including E1 (Neutrino Factories and Muon Colliders), M1 (Muon Based Systems), M6 (High Intensity Proton Sources), T4 (Particle sources), T5 (Beam dynamics), and T8 (Advanced Accelerators). The topics that were discussed fall naturally into three areas: (1) HPC requirements for next-generation accelerator design, (2) state-of-the-art in HPC simulation of accelerator systems, and (3) applied mathematics and computer science activities related to the development of HPC tools that will be of use to the accelerator community (as well as other communities). This document summarizes the material mentioned above and includes recommendations for future HPC activities in the accelerator community. The relationship of those activities to the HENP/SciDAC project on 21st century accelerator simulation is also discussed.

  9. A performance-based method for calculating the design thickness of compacted clay liners exposed to high strength leachate under simulated landfill conditions.

    PubMed

    Safari, Edwin; Jalili Ghazizade, Mahdi; Abdoli, Mohammad Ali

    2012-09-01

    Compacted clay liners (CCLs) when feasible, are preferred to composite geosynthetic liners. The thickness of CCLs is typically prescribed by each country's environmental protection regulations. However, considering the fact that construction of CCLs represents a significant portion of overall landfill construction costs; a performance based design of liner thickness would be preferable to 'one size fits all' prescriptive standards. In this study researchers analyzed the hydraulic behaviour of a compacted clayey soil in three laboratory pilot scale columns exposed to high strength leachate under simulated landfill conditions. The temperature of the simulated CCL at the surface was maintained at 40 ± 2 °C and a vertical pressure of 250 kPa was applied to the soil through a gravel layer on top of the 50 cm thick CCL where high strength fresh leachate was circulated at heads of 15 and 30 cm simulating the flow over the CCL. Inverse modelling using HYDRUS-1D indicated that the hydraulic conductivity after 180 days was decreased about three orders of magnitude in comparison with the values measured prior to the experiment. A number of scenarios of different leachate heads and persistence time were considered and saturation depth of the CCL was predicted through modelling. Under a typical leachate head of 30 cm, the saturation depth was predicted to be less than 60 cm for a persistence time of 3 years. This approach can be generalized to estimate an effective thickness of a CCL instead of using prescribed values, which may be conservatively overdesigned and thus unduly costly. PMID:22617473

  10. Dose response of multiple parameters for calyculin A-induced premature chromosome condensation in human peripheral blood lymphocytes exposed to high doses of cobalt-60 gamma-rays.

    PubMed

    Lu, Xue; Zhao, Hua; Feng, Jiang-Bin; Zhao, Xiao-Tao; Chen, De-Qing; Liu, Qing-Jie

    2016-09-01

    Many studies have investigated exposure biomarkers for high dose radiation. However, no systematic study on which biomarkers can be used in dose estimation through premature chromosome condensation (PCC) analysis has been conducted. The present study aims to screen the high-dose radiation exposure indicator in calyculin A-induced PCC. The dose response of multiple biological endpoints, including G2/A-PCC (G2/M and M/A-PCC) index, PCC ring (PCC-R), ratio of the longest/shortest length (L/L ratio), and length and width ratio of the longest chromosome (L/B ratio), were investigated in calyculin A-induced G2/A-PCC spreads in human peripheral blood lymphocytes exposed to 0-20Gy (dose-rate of 1Gy/min) cobalt-60 gamma-rays. The G2/A-PCC index was decreased with enhanced absorbed doses of 4-20Gy gamma-rays. The G2/A PCC-R at 0-12Gy gamma-rays conformed to Poisson distribution. Three types of PCC-R were scored according to their shape and their solidity or hollowness. The frequencies of hollow PCC-R and PCC-R including or excluding solid ring in G2/A-PCC spreads were enhanced with increased doses. The length and width of the longest chromosome, as well as the length of the shortest chromosome in each G2/M-PCC or M/A-PCC spread, were measured. All L/L or L/B ratios in G2/M-PCC or M/A-PCC spread increased with enhanced doses. A blind test with two new irradiated doses was conducted to validate which biomarker could be used in dose estimation. Results showed that hollow PCC-R and PCC-R including solid ring can be utilized for accurate dose estimation, and that hollow PCC-R was optimal for practical application.

  11. A performance-based method for calculating the design thickness of compacted clay liners exposed to high strength leachate under simulated landfill conditions.

    PubMed

    Safari, Edwin; Jalili Ghazizade, Mahdi; Abdoli, Mohammad Ali

    2012-09-01

    Compacted clay liners (CCLs) when feasible, are preferred to composite geosynthetic liners. The thickness of CCLs is typically prescribed by each country's environmental protection regulations. However, considering the fact that construction of CCLs represents a significant portion of overall landfill construction costs; a performance based design of liner thickness would be preferable to 'one size fits all' prescriptive standards. In this study researchers analyzed the hydraulic behaviour of a compacted clayey soil in three laboratory pilot scale columns exposed to high strength leachate under simulated landfill conditions. The temperature of the simulated CCL at the surface was maintained at 40 ± 2 °C and a vertical pressure of 250 kPa was applied to the soil through a gravel layer on top of the 50 cm thick CCL where high strength fresh leachate was circulated at heads of 15 and 30 cm simulating the flow over the CCL. Inverse modelling using HYDRUS-1D indicated that the hydraulic conductivity after 180 days was decreased about three orders of magnitude in comparison with the values measured prior to the experiment. A number of scenarios of different leachate heads and persistence time were considered and saturation depth of the CCL was predicted through modelling. Under a typical leachate head of 30 cm, the saturation depth was predicted to be less than 60 cm for a persistence time of 3 years. This approach can be generalized to estimate an effective thickness of a CCL instead of using prescribed values, which may be conservatively overdesigned and thus unduly costly.

  12. Is screening for pharyngeal Chlamydia trachomatis warranted in high-risk groups?

    PubMed

    Tipple, C; Hill, S C; Smith, A

    2010-11-01

    A recent survey reported that 36% of UK genitourinary medicine clinics offer testing for pharyngeal Chlamydia trachomatis (CT). Screening at this site is targeted at high-risk groups attending our centre, including female sex workers (FSWs) and male sex workers (MSWs). A total of 2406 patients were screened between November 2006 and October 2007. A retrospective case-note review was performed for positive cases. The prevalence of pharyngeal CT was 1.9% in both men and women. The mean number of sexual partners reported in the preceding three months was 168 and 56 for FSWs and MSWs, respectively. Lack of consistent condom use and high numbers of sexual partners identify this population as potential core transmitters of infection. While the British Association of Sexual Health and HIV (BASHH) guidelines do not recommend routine screening for pharyngeal CT, there may be a role in selected high-risk populations.

  13. Is screening for pharyngeal Chlamydia trachomatis warranted in high-risk groups?

    PubMed

    Tipple, C; Hill, S C; Smith, A

    2010-11-01

    A recent survey reported that 36% of UK genitourinary medicine clinics offer testing for pharyngeal Chlamydia trachomatis (CT). Screening at this site is targeted at high-risk groups attending our centre, including female sex workers (FSWs) and male sex workers (MSWs). A total of 2406 patients were screened between November 2006 and October 2007. A retrospective case-note review was performed for positive cases. The prevalence of pharyngeal CT was 1.9% in both men and women. The mean number of sexual partners reported in the preceding three months was 168 and 56 for FSWs and MSWs, respectively. Lack of consistent condom use and high numbers of sexual partners identify this population as potential core transmitters of infection. While the British Association of Sexual Health and HIV (BASHH) guidelines do not recommend routine screening for pharyngeal CT, there may be a role in selected high-risk populations. PMID:21187360

  14. Using focus groups to develop a nutrition education video for high school students.

    PubMed

    James, D C; Rienzo, B A; Frazee, C

    1997-11-01

    Focus group interviews were used to develop a nutrition education video and a teacher's guide for use in Florida high schools. Authors conducted a pilot and four focus group interviews with ninth grade students in five geographically distinct regions of Florida. Most students agreed that a video with scenarios or success stories would work well. Teens expressed interest in 10 topics: eating disorders; consequences of unhealthy eating; preparing quick, healthy meals; what constitutes a balanced diet; nutrition and fitness; weight control; food and the environment; the food guide pyramid; nutrition facts and fallacies; and food labels. Students suggested no more than three or four topics should be covered in the video, and the video cast should consist mainly of teen-agers with different body sizes, who were average, attractive, and from different ethnic backgrounds. Music was recommended only for transitions between scenes, as background, or during the credits. PMID:9471089

  15. High-Density Plasma Etching of Group-III Nitride Films for Device Application

    SciTech Connect

    Baca, A.G.; Crawford, M.H.; Han, J.; Lester, L.F.; Pearton, S.J.; Ren, F.; Shul, R.J.; Willison, C.G.; Zhang, L.; Zolper, J.C.

    1999-02-17

    As III-V nitride device structures become more complicated and design rules shrink, well-controlled etch processes are necessary. Due to limited wet chemical etch results for the group-III nitrides, a significant amount of effort has been devoted to the development of dry etch processing. Dry etch development was initially focused on mesa structures where high etch rates, anisotropic profiles, smooth sidewalls, and equi-rate etching of dissimilar materials were required. For example, commercially available LEDs and laser facets for GaN-based laser diodes have been patterned using reactive ion etching (RIE). With the recent interest in high power, high temperature electronic devices, etch characteristics may also require smooth surface morphology, low plasma-induced damage, and selective etching of one layer over another. The principal criteria for any plasma etch process is its utility in the fabrication of a device. In this study, we will report plasma etch results for the group-III nitrides and their application to device structures.

  16. Necrotizing fasciitis secondary to group A streptococcus. Morbidity and mortality still high.

    PubMed Central

    Leitch, H. A.; Palepu, A.; Fernandes, C. M.

    2000-01-01

    OBJECTIVE: To update physicians on Group A streptococcal necrotizing fasciitis, including current methods of diagnosis and treatment. QUALITY OF EVIDENCE: Current literature (1990-1998) was searched via MEDLINE using the MeSH headings necrotizing fasciitis, toxic shock syndrome, and Streptococcus. Articles were selected based on clinical relevance and design. Most were case reports, case series, or population-based surveys. There were no randomized controlled trials. MAIN MESSAGE: The hallmark of clinical diagnosis of necrotizing fasciitis is pain out of proportion to physical findings. Suspicion of underlying soft tissue infection should prompt urgent surgical examination. Therapy consists of definitive excisional surgical debridement in conjunction with high-dose intravenous penicillin G and clindamicin. Risk factors for mortality include advanced age, underlying illness, hypotension, and bacteremia. CONCLUSION: Necrotizing soft tissue infections due to Group A streptococcus might be increasing in frequency and aggression. Overall mortality remains high (20% to 34% in larger series). Clinical diagnosis requires a high level of suspicion and should prompt urgent surgical referral. Images Figure 1 Figure 2 PMID:10925760

  17. Biochemical markers in butadiene-exposed workers

    SciTech Connect

    Bechtold, W.E.; Hayes, R.B.; Thornton-Manning, J.R.; Henderson, R.F.

    1994-11-01

    1,3-Butadiene (BD) is used to manufacture a wide range of polymers and copolymers including styrene-butadiene rubber, polybutadiene, and acrylonitrile-butadiene-syrene resins. The carcinogenicity of BD has been determined in life-span inhalation studies in both Sprague-Dawley rats and B6C3F{sub 1} mice. Results suggest a marked species difference in the carcinogenic effects of BD. For example, female mice exposed to as low as 6.25 ppm BD exhibited increased alveolar/bronchiolar neoplasms. In contrast, BD was only a weak carcinogen in Sprague-Dawley rats. Rats were observed to have an increase only in mammary tumors after exposure to 1000 ppm. A biochemical study of highly exposed BD workers and unexposed controls is providing valuable information on BD metabolism in humans, and how this relates to the development of intermediate biologic effects. A group of heavily exposed workers were identified in a BD production facility in China. The purpose of this paper is to report the initial results from the sampling trip in the first quarter of 1994.

  18. Working group II report: Production and dynamics of high brightness beams

    SciTech Connect

    Sheffield, R.L.

    1996-12-31

    This paper summarizes the main discussions of the Working Group on the Production and Dynamics of High Brightness Beams. The following topics are covered in this paper. Proposed new electron sources and needed research on existing sources is covered. The discussions on issues relating to the description of phase space on non-thermalized electron beam distributions and the theoretical modeling on non-thermalized electron beam distributions is presented. Finally, the present status of the theoretical modeling of beam transport in bends is given.

  19. High Energy Accelerator and Colliding Beam User Group. Progress report, May 1, 1980--March 31, 1981

    SciTech Connect

    Snow, G.A.

    1980-12-01

    The major activities of the High Energy Physics Group at the University of Maryland during the current contract period have been: analysis of e{sup +}e{sup {minus}} events from the PLUTO detector at PETRA, design and construction of modifications to PLUTO for 2{gamma} physics, analyses of {nu}{sub {mu}}D{sub 2} bubble chamber pictures from Fermilab, completion of the {nu}{sub {mu}}e elastic scattering experiment at Fermilab, development and demonstration of an ultra cold neutron source produced by Doppler shifting, testing of equipment for the hadron jet experiment at Fermilab that is about to begin, and planning for large projects in the future.

  20. Proteolytic inactivation of nuclear alarmin high-mobility group box 1 by complement protease C1s during apoptosis

    PubMed Central

    Yeo, J G; Leong, J; Arkachaisri, T; Cai, Y; Teo, B H D; Tan, J H T; Das, L; Lu, J

    2016-01-01

    Effective clearance of apoptotic cells by phagocytes prevents the release of intracellular alarmins and manifestation of autoimmunity. This prompt efferocytosis is complemented by intracellular proteolytic degradation that occurs within the apoptotic cells and in the efferosome of the phagocytes. Although the role of extracellular proteases in apoptotic cells clearance is unknown, the strong association of congenital C1s deficiency with Systemic Lupus Erythematosus highlights the protective nature that this extracellular protease has against autoimmunity. The archetypical role of serine protease C1s as the catalytic arm of C1 complex (C1qC1r2C1s2) involve in the propagation of the classical complement pathway could not provide the biological basis for this association. However, a recent observation of the ability of C1 complex to cleave a spectrum of intracellular cryptic targets exposed during apoptosis provides a valuable insight to the underlying protective mechanism. High-mobility group box 1 (HMGB1), an intracellular alarmin that is capable of inducing the formation of antinuclear autoantibodies and causes lupus-like conditions in mice, is identified as a novel potential target by bioinformatics analysis. This is verified experimentally with C1s, both in its purified and physiological form as C1 complex, cleaving HMGB1 into defined fragments of 19 and 12 kDa. This cleavage diminishes HMGB1 ability to enhance lipopolysaccharide mediated pro-inflammatory cytokines production from monocytes, macrophages and dendritic cells. Further mass spectrometric analysis of the C1 complex treated apoptotic cellular proteins demonstrated additional C1s substrates and revealed the complementary role of C1s in apoptotic cells clearance through the proteolytic cleavage of intracellular alarmins and autoantigens. C1 complex may have evolved as, besides the bacteriolytic arm of antibodies in which it activates the complement cascade, a tissue renewal mechanism that reduces the

  1. Proteolytic inactivation of nuclear alarmin high-mobility group box 1 by complement protease C1s during apoptosis

    PubMed Central

    Yeo, J G; Leong, J; Arkachaisri, T; Cai, Y; Teo, B H D; Tan, J H T; Das, L; Lu, J

    2016-01-01

    Effective clearance of apoptotic cells by phagocytes prevents the release of intracellular alarmins and manifestation of autoimmunity. This prompt efferocytosis is complemented by intracellular proteolytic degradation that occurs within the apoptotic cells and in the efferosome of the phagocytes. Although the role of extracellular proteases in apoptotic cells clearance is unknown, the strong association of congenital C1s deficiency with Systemic Lupus Erythematosus highlights the protective nature that this extracellular protease has against autoimmunity. The archetypical role of serine protease C1s as the catalytic arm of C1 complex (C1qC1r2C1s2) involve in the propagation of the classical complement pathway could not provide the biological basis for this association. However, a recent observation of the ability of C1 complex to cleave a spectrum of intracellular cryptic targets exposed during apoptosis provides a valuable insight to the underlying protective mechanism. High-mobility group box 1 (HMGB1), an intracellular alarmin that is capable of inducing the formation of antinuclear autoantibodies and causes lupus-like conditions in mice, is identified as a novel potential target by bioinformatics analysis. This is verified experimentally with C1s, both in its purified and physiological form as C1 complex, cleaving HMGB1 into defined fragments of 19 and 12 kDa. This cleavage diminishes HMGB1 ability to enhance lipopolysaccharide mediated pro-inflammatory cytokines production from monocytes, macrophages and dendritic cells. Further mass spectrometric analysis of the C1 complex treated apoptotic cellular proteins demonstrated additional C1s substrates and revealed the complementary role of C1s in apoptotic cells clearance through the proteolytic cleavage of intracellular alarmins and autoantigens. C1 complex may have evolved as, besides the bacteriolytic arm of antibodies in which it activates the complement cascade, a tissue renewal mechanism that reduces the

  2. Proteolytic inactivation of nuclear alarmin high-mobility group box 1 by complement protease C1s during apoptosis.

    PubMed

    Yeo, J G; Leong, J; Arkachaisri, T; Cai, Y; Teo, B H D; Tan, J H T; Das, L; Lu, J

    2016-01-01

    Effective clearance of apoptotic cells by phagocytes prevents the release of intracellular alarmins and manifestation of autoimmunity. This prompt efferocytosis is complemented by intracellular proteolytic degradation that occurs within the apoptotic cells and in the efferosome of the phagocytes. Although the role of extracellular proteases in apoptotic cells clearance is unknown, the strong association of congenital C1s deficiency with Systemic Lupus Erythematosus highlights the protective nature that this extracellular protease has against autoimmunity. The archetypical role of serine protease C1s as the catalytic arm of C1 complex (C1qC1r2C1s2) involve in the propagation of the classical complement pathway could not provide the biological basis for this association. However, a recent observation of the ability of C1 complex to cleave a spectrum of intracellular cryptic targets exposed during apoptosis provides a valuable insight to the underlying protective mechanism. High-mobility group box 1 (HMGB1), an intracellular alarmin that is capable of inducing the formation of antinuclear autoantibodies and causes lupus-like conditions in mice, is identified as a novel potential target by bioinformatics analysis. This is verified experimentally with C1s, both in its purified and physiological form as C1 complex, cleaving HMGB1 into defined fragments of 19 and 12 kDa. This cleavage diminishes HMGB1 ability to enhance lipopolysaccharide mediated pro-inflammatory cytokines production from monocytes, macrophages and dendritic cells. Further mass spectrometric analysis of the C1 complex treated apoptotic cellular proteins demonstrated additional C1s substrates and revealed the complementary role of C1s in apoptotic cells clearance through the proteolytic cleavage of intracellular alarmins and autoantigens. C1 complex may have evolved as, besides the bacteriolytic arm of antibodies in which it activates the complement cascade, a tissue renewal mechanism that reduces the

  3. Cytomegalovirus pneumonitis and bone marrow transplantation: identification of a specific high risk group.

    PubMed Central

    Foot, A B; Caul, E O; Roome, A P; Darville, J M; Oakhill, A

    1993-01-01

    AIMS--To study the association between cytomegalovirus (CMV) excretion and interstitial pneumonitis in allogeneic bone marrow transplant (BMT) recipients, with reference to donor and recipient CMV antibody response. METHODS--The incidence of CMV excretion was prospectively studied in 62 allogeneic bone marrow transplantations performed on adults and children. All recipients received CMV seronegative blood products. Prophylaxis with high dose acyclovir and CMV immune globulin was given to high risk patients (donor or recipient, or both, CMV seropositive). RESULTS--CMV excretion was detected in eight of 26 (31%) high risk patients but in only one of 36 low risk patients (donor and recipient both CMV seronegative). Five of the eight (63%) excretors in the high risk category developed CMV, of whom four (80%) belonged to the seropositive recipient/seronegative donor group, and included the three CMV seropositive recipients whose CMV complement fixation antibody titres were 64 or greater before transplantation. CONCLUSIONS--These findings suggest that there is a subgroup of patients at especially high risk of developing CMV. PMID:8391547

  4. High-Throughput System for the Presentation of Secreted and Surface-Exposed Proteins from Gram-Positive Bacteria in Functional Metagenomics Studies

    PubMed Central

    Dobrijevic, Dragana; Di Liberto, Gaetana; Tanaka, Kosei; de Wouters, Tomas; Dervyn, Rozenn; Boudebbouze, Samira; Binesse, Johan; Blottière, Hervé M.; Jamet, Alexandre; Maguin, Emmanuelle; van de Guchte, Maarten

    2013-01-01

    Complex microbial ecosystems are increasingly studied through the use of metagenomics approaches. Overwhelming amounts of DNA sequence data are generated to describe the ecosystems, and allow to search for correlations between gene occurrence and clinical (e.g. in studies of the gut microbiota), physico-chemical (e.g. in studies of soil or water environments), or other parameters. Observed correlations can then be used to formulate hypotheses concerning microbial gene functions in relation to the ecosystem studied. In this context, functional metagenomics studies aim to validate these hypotheses and to explore the mechanisms involved. One possible approach is to PCR amplify or chemically synthesize genes of interest and to express them in a suitable host in order to study their function. For bacterial genes, Escherichia coli is often used as the expression host but, depending on the origin and nature of the genes of interest and the test system used to evaluate their putative function, other expression systems may be preferable. In this study, we developed a system to evaluate the role of secreted and surface-exposed proteins from Gram-positive bacteria in the human gut microbiota in immune modulation. We chose to use a Gram-positive host bacterium, Bacillus subtilis, and modified it to provide an expression background that behaves neutral in a cell-based immune modulation assay, in vitro. We also adapted an E. coli – B. subtilis shuttle expression vector for use with the Gateway high-throughput cloning system. Finally, we demonstrate the functionality of this host-vector system through the cloning and expression of a flagellin-coding sequence, and show that the expression-clone elicits an inflammatory response in a human intestinal epithelial cell line. The expression host can easily be adapted to assure neutrality in other assay systems, allowing the use of the presented presentation system in functional metagenomics of the gut and other ecosystems. PMID

  5. Hubble Space Telescope high resolution spectroscoy of the exposed white dwarf in the dwarf nova VW Hydri in quiescence: A rapidly rotating white dwarf

    NASA Technical Reports Server (NTRS)

    Sion, Edward M.; Huang, Min; Szkody, Paula; Cheng, Fu-Hua

    1995-01-01

    We obtained a far-ultraviolet spectrum of the dwarf nova VW Hyi in quiescence, with the Hubble Space Telescope Goddard High Resolution Spectrograph covering the region of the Si iv lambda(lambda)1393, 1402 resonance doublet. The broad, shallow Si iv doublet feature is fully resolved, has a total equivalent width of 2.8 A, and is the first metal absorption feature to be clearly detected in the exposed white dwarf. Our synthetic spectral analysis, using a model grid constructed with the code TLUSTY, resulted in a reasonable fit to a white dwarf photosphere with T(sub eff) = 22,000 +/- 2000 K, log g = 8.0 +/- 0.3, an approximately solar Si/H abundance, and a rotational velocity, v sin i approximately equal to 600 km/s. This rotation rate, while not definitive because it is based upon just one line transition, is 20% of the Keplerian (breakup) velocity of the white dwarf and hence does not account for the unexpectedly low boundary-layer luminosity inferred from the soft-X-ray/extreme ultra-violet bands where most of the boundary-layer luminosity should be radiated. The predicted boundary-layer luminosity for a 0.6 solar mass white dwarf accreting at the rate 10(exp -10) solar mass/yr and rotating at 600 km/s, corresponding to VW Hyi in quiescence, is 2 x 10(exp 32) ergs/s when proper account is taken of the rotational kinetic energy going into spinning up the white dwarf. If the boundary-layer area is equal to that of the white dwarf, then T(sub bl) = 24,000 K. This is essentially identical to the photspheric luminosity and temperature determined in far-ultraviolet photospheric analyses. If the boundary-layer area is 10(exp -3) of the white dwarf surface area, then T(sub bl) = 136,000 K.

  6. Profiles of Reactivity in Cocaine-Exposed Children

    PubMed Central

    Schuetze, Pamela; Molnar, Danielle S.; Eiden, Rina D.

    2012-01-01

    This study explored the possibility that specific, theoretically consistent profiles of reactivity could be identified in a sample of cocaine-exposed infants and whether these profiles were associated with a range of infant and/or maternal characteristics. Cluster analysis was used to identify distinct groups of infants based on physiological, behavioral and maternal reported measures of reactivity. Five replicable clusters were identified which corresponded to 1) Dysregulated/High Maternal Report Reactors, 2) Low Behavioral Reactors, 3) High Reactors, 4) Optimal Reactors and 5) Dysregulated/Low Maternal Report Reactors. These clusters were associated with differences in prenatal cocaine exposure status, birthweight, maternal depressive symptoms, and maternal negative affect during mother-infant interactions. These results support the presence of distinct reactivity profiles among high risk infants recruited on the basis of prenatal cocaine exposure and demographically similar control group infants not exposed to cocaine. PMID:23204615

  7. High temperature fuel cell membranes based on poly(arylene ether)s containing benzimidazole groups

    SciTech Connect

    Kim, Dae Sik; Kim, Yu Seung; Lee, Kwan - Soo; Boncella, James M; Kuiper, David; Guiver, Michael D

    2009-01-01

    Development of new high-performance polymer membranes that retain their proton conductivity under low humidity conditions is one of the most critical requirements to commercialize PEMFC systems. Current sulfonated proton exchange membranes acquire proton conductivity by water that solvates ion and carries proton. Consequently, a loss of water under low RH conditions immediately results in a loss of proton conductivity. One approach to maintain proton conductivity under low RH conditions is to replace water with a less volatile proton solvent. Kreuer has pointed out the possibility to develop fully polymeric proton-conducting membranes based on nitrogen-containing heterocycles such as imidazole, benzimidazole, and pyrazole. We have attempted to blend those less volatile proton solvent with sulfonated copolymers such as polystyrene sulfonic acid, Nafion, poly(arylene ether sulfone, BPSH-xx). [Ref. DOE review meeting 2007 and 2008] However, we observed that imidazole was slowly sublimated out as temperature and humidity increases which could cause poisoning of electro-catalyst, corrosion and losing conductivity. In this presentation, we report the synthesis of novel poly(arylene ether sulfone)s containing benzimidazole groups These benzimidazole containing polymer was blended with sulfonated poly(arylene ether sulfone). In the blend system, benzimidazole group attached to the polysulfone acts as a medium through the basic nitrogen for transfer of protons between the sulfonic acid groups. Proton conductivity of the blend membranes was investigated as a function of water content at 80 C and compared the performance with water based proton conduction system.

  8. Assessment of low ABSPI among arsenic exposed and non-exposed populations: a pilot study.

    PubMed

    Khan, Manzurul Haque; Sarkar, Sudipta; Khan, Nasreen; Sarwar, A F M; Ahmad, S Akhtar

    2010-04-01

    This cross-sectional study was carried out to assess and compare Ankle Brachial Systolic Pressure Index (ABSPI) amongst 120 arsenic exposed and 120 non-exposed populations of Samta village in Bangladesh. Abnormal ABSPI was more prevalent in arsenic exposed (13.3%) than in non-exposed (2.5%) group. The prevalence of abnormal ABSPI for respondents when adjusted for age, sex, BMI, blood pressure status and diabetic status, the prevalence remain significantly different. The findings suggest that those exposed to arsenic have increased chance of having abnormal ABSP and hence increased chance of peripheral arterial disease in Bangladesh.

  9. A simple colorimetric chemosensor bearing a carboxylic acid group with high selectivity for CN-

    NASA Astrophysics Data System (ADS)

    Park, Gyeong Jin; Choi, Ye Won; Lee, Dongkuk; Kim, Cheal

    2014-11-01

    A new simple ‘naked eye' chemosensor 1 (sodium (E)-2-((2-(3-hydroxy-2-naphthoyl)hydrazono)methyl)benzoate) has been synthesized for detection of CN- in a mixture of DMF/H2O (9:1). The sensor 1 comprises of a naphthoic hydrazide as efficient hydrogen bonding donor group and a benzoic acid as the moiety with the water solubility. The receptor 1 showed high selectivity toward cyanide ions in a 1:1 stoichiometric manner, which induces a fast color change from colorless to yellow for CN- over other anions. Therefore, receptor 1 could be useful for cyanide detection in aqueous environment, displaying a high distinguishable selectivity from hydrogen bonded anions and being clearly visible to the naked eye.

  10. High energy accelerator and colliding beam user group: Progress report, March 1, 1987-February 29, 1988

    SciTech Connect

    Not Available

    1987-09-01

    Progress is reported on the OPAL experiment at LEP, including construction and assembly of the hadron calorimeter and development of OPAL software. Progress on the JADE experiment, which examines e/sup +/e/sup -/ interactions at PETRA, and of the PLUTO collaboration are also discussed. Experiments at Fermilab are reported, including deep inelastic muon scattering at TeV II, the D0 experiment at TeV I, and hadron jet physics. Neutrino-electron elastic scattering and a search for point-sources of ultra-high energy cosmic rays are reported. Other activities discussed include polarization in electron storage rings, participation in studies for the SSC and LEP 200, neutron-antineutron oscillations, and the work of the electronics support group. High energy physics computer experience is also discussed. 158 refs. (LEW)

  11. High mobility group-like proteins of the insect Plodia interpunctella.

    PubMed

    Aleporou-Marinou, Vassiliki; Drosos, Yianis; Ninios, Yiannis; Agelopoulou, Barbara; Patargias, Theocharis

    2003-02-01

    Nuclei from Plodia interpunctella larvae contain four major proteins, which are extracted by 5% perchloric acid and 0.35 M NaCl. The proteins have been designated PL1, PL2, PL3, and PL4. The amino acid analyses of these proteins show that they have high proportions of acidic and basic amino acid residues, a property characteristic of the high mobility group (HMG) proteins isolated from vertebrate tissues. Immunological characterication of these proteins clearly shows that PL1, PL2, and PL4 are more closely related to HMG1 dipteran proteins, while PL3 is more closely related to HMG1 dipteran proteins. The possible relatedness of these proteins to HMG proteins is discussed.

  12. A dangerous duo in adipose tissue: high-mobility group box 1 protein and macrophages.

    PubMed

    Wagner, Marek

    2014-06-01

    High-mobility group box 1 (HMGB1) protein first made headlines 40 years ago as a non-histone nuclear protein that regulates gene expression. Not so long ago, it was also shown that HMGB1 has an additional surprising function. When released into the extracellular milieu, HMGB1 triggers an inflammatory response by serving as an endogenous danger signal. The pro-inflammatory role of HMGB1 is now well-established and has been associated with several diseases, including sepsis, rheumatoid arthritis, and atherosclerosis. Yet very little is known about its role in obesity, wherein adipose tissue is typified by a persistent, smoldering inflammatory response instigated by high macrophage infiltrate that potentiates the risk of obesity-associated comorbidities. This mini-review focuses on the putative causal relationship between HMGB1 and macrophage pro-inflammatory activation in pathologically altered adipose tissue associated with obesity.

  13. Renormalization group evolution of multi-gluon correlators in high energy QCD

    NASA Astrophysics Data System (ADS)

    Dumitru, A.; Jalilian-Marian, J.; Lappi, T.; Schenke, B.; Venugopalan, R.

    2011-12-01

    Many-body QCD in leading high energy Regge asymptotics is described by the Balitsky-JIMWLK hierarchy of renormalization group equations for the x evolution of multi-point Wilson line correlators. These correlators are universal and ubiquitous in final states in deeply inelastic scattering and hadronic collisions. For instance, recently measured di-hadron correlations at forward rapidity in deuteron-gold collisions at the Relativistic Heavy Ion Collider (RHIC) are sensitive to four and six point correlators of Wilson lines in the small x color fields of the dense nuclear target. We evaluate these correlators numerically by solving the functional Langevin equation that describes the Balitsky-JIMWLK hierarchy. We compare the results to mean-field Gaussian and large Nc approximations used in previous phenomenological studies. We comment on the implications of our results for quantitative studies of multi-gluon final states in high energy QCD.

  14. A dangerous duo in adipose tissue: high-mobility group box 1 protein and macrophages.

    PubMed

    Wagner, Marek

    2014-06-01

    High-mobility group box 1 (HMGB1) protein first made headlines 40 years ago as a non-histone nuclear protein that regulates gene expression. Not so long ago, it was also shown that HMGB1 has an additional surprising function. When released into the extracellular milieu, HMGB1 triggers an inflammatory response by serving as an endogenous danger signal. The pro-inflammatory role of HMGB1 is now well-established and has been associated with several diseases, including sepsis, rheumatoid arthritis, and atherosclerosis. Yet very little is known about its role in obesity, wherein adipose tissue is typified by a persistent, smoldering inflammatory response instigated by high macrophage infiltrate that potentiates the risk of obesity-associated comorbidities. This mini-review focuses on the putative causal relationship between HMGB1 and macrophage pro-inflammatory activation in pathologically altered adipose tissue associated with obesity. PMID:24910558

  15. Developmental trajectories of cocaine-and-other-drug-exposed and non-cocaine-exposed children.

    PubMed

    Mayes, Linda C; Cicchetti, Domenic; Acharyya, Suddhasatta; Zhang, Heping

    2003-10-01

    Few data are available concerning the trajectories of mental and motor development across time for cocaine-exposed children compared with others. Findings are presented from individual group curve analyses of the mental and motor development measured by the Bayley Scales of Infant Development-II (BSID-II) on repeated visits from 3 through 36 months of a group of prenatally cocaine-and-other-drug-exposed children (n = 265) compared with those exposed to no drugs (n = 129) or no-cocaine-but-other-drugs (n = 66), including alcohol and/or tobacco. Across time, there was a general decline in motor performance but cocaine-exposed-infants showed a trend toward a greater decrease than children in the other two comparison groups. For mental performance, there was also a decline across age but only through 24 months and no differences in the trajectory of the cocaine-exposed group compared to the other two. And, across all assessment ages, cocaine-exposed-infants showed lower BSID-II mental performance compared to both non-drug and non-cocaine-exposed children. Results suggest that prenatally cocaine-exposed children show delayed developmental indices, particularly in their mental performance, but their trajectories across time are similar to those from impoverished, non-cocaine-exposed groups. PMID:14578693

  16. High-temperature mass spectrometry - Vaporization of group 4-B metal carbides. [using Knudsen effusion

    NASA Technical Reports Server (NTRS)

    Stearns, C. A.; Kohl, F. J.

    1974-01-01

    The high temperature vaporization of the metal-carbon systems TiC, ZrC, HfC, and ThC was studied by the Knudsen effusion - mass spectrometric method. For each system the metal dicarbide and tetracarbide molecular species were identified in the gas phase. Relative ion currents of the carbides and metals were measured as a function of temperature. Second- and third-law methods were used to determine enthalpies. Maximum values were established for the dissociation energies of the metal monocarbide molecules TiC, ZrC, HfC, and ThC. Thermodynamic functions used in the calculations are discussed in terms of assumed molecular structures and electronic contributions to the partition functions. The trends shown by the dissociation energies of the carbides of Group 4B are compared with those of neighboring groups and discussed in relation to the corresponding oxides and chemical bonding. The high temperature molecular beam inlet system and double focusing mass spectrometer are described.

  17. Exploring the development of classroom group identities in an urban high school chemistry class

    NASA Astrophysics Data System (ADS)

    Macaluso, Stefania

    A key to achieving academic success in science is providing students with meaningful experiences and skills to negotiate how these experiences affect them and the society in which they live. Although students strive for academic success, a challenge that faces many urban science students and their teachers is finding ways to promote student engagement in the science classroom. In order to support students in urban settings and to better identify the ways in which students may better learn science concepts and develop a sense of belonging or affiliation to science, this qualitative research study explores the development of a classroom group identity (CGI) based on the frameworks of social identity theory, interaction ritual chain theory, and communities of practice. The interactions and experiences of eighteen student participants in a Bronx high school chemistry class were studied over the course of a full school year. Using a conceptual lens of classroom group identity, a model construct and definition were built identifying four stages of CGI development. At the culmination of the study, a positive change in perceptions, attitudes, leadership skills, and classroom behaviors in learning science was primarily observed by two students developing a CGI. The study has implications for the teaching and learning of high school sciences.

  18. Projection of human immunodeficiency virus among high-risk groups in Malaysia.

    PubMed

    Mondal, Md Nazrul Islam; Shitan, Mahendran

    2013-01-01

    Human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) presents a serious healthcare threat to young individuals in Malaysia and worldwide. This study aimed to identify trends in HIV-related risk behaviors among recognized high-risk groups and to estimate HIV transmission up to the year 2015. Data and necessary information were obtained from the Ministry of Health Malaysia, published reports from the World Health Organization and United Nations Program on HIV/AIDS, and other articles. The Estimation and Projection Package was used to estimate HIV transmission. The results of the present study revealed that within the high-risk groups, intravenous drug users (IDUs) had the highest prevalence rate of HIV transmission, followed by patients with sexually transmitted infections (STIs), female sex workers (SWs), and men who have sex with men (MSM). Within these at-risk populations, patients with STIs have the highest prevalence of HIV, followed by IDUs, MSM, and SWs. If the transmission rate continues to increase, the situation will worsen; therefore, there is an urgent need for a comprehensive prevention program to control HIV transmission in Malaysia. PMID:24047742

  19. Dose response of multiple parameters for calyculin A-induced premature chromosome condensation in human peripheral blood lymphocytes exposed to high doses of cobalt-60 gamma-rays.

    PubMed

    Lu, Xue; Zhao, Hua; Feng, Jiang-Bin; Zhao, Xiao-Tao; Chen, De-Qing; Liu, Qing-Jie

    2016-09-01

    Many studies have investigated exposure biomarkers for high dose radiation. However, no systematic study on which biomarkers can be used in dose estimation through premature chromosome condensation (PCC) analysis has been conducted. The present study aims to screen the high-dose radiation exposure indicator in calyculin A-induced PCC. The dose response of multiple biological endpoints, including G2/A-PCC (G2/M and M/A-PCC) index, PCC ring (PCC-R), ratio of the longest/shortest length (L/L ratio), and length and width ratio of the longest chromosome (L/B ratio), were investigated in calyculin A-induced G2/A-PCC spreads in human peripheral blood lymphocytes exposed to 0-20Gy (dose-rate of 1Gy/min) cobalt-60 gamma-rays. The G2/A-PCC index was decreased with enhanced absorbed doses of 4-20Gy gamma-rays. The G2/A PCC-R at 0-12Gy gamma-rays conformed to Poisson distribution. Three types of PCC-R were scored according to their shape and their solidity or hollowness. The frequencies of hollow PCC-R and PCC-R including or excluding solid ring in G2/A-PCC spreads were enhanced with increased doses. The length and width of the longest chromosome, as well as the length of the shortest chromosome in each G2/M-PCC or M/A-PCC spread, were measured. All L/L or L/B ratios in G2/M-PCC or M/A-PCC spread increased with enhanced doses. A blind test with two new irradiated doses was conducted to validate which biomarker could be used in dose estimation. Results showed that hollow PCC-R and PCC-R including solid ring can be utilized for accurate dose estimation, and that hollow PCC-R was optimal for practical application. PMID:27542714

  20. Prenatal Exposure to p,p′-DDE and p,p′-DDT in Relation to Lower Respiratory Tract Infections in Boys From a Highly Exposed Area of Mexico

    PubMed Central

    Cupul-Uicab, Lea A.; Terrazas-Medina, Efraín A.; Hernández-Ávila, Mauricio; Longnecker, Matthew P.

    2014-01-01

    Background Prenatal exposure to 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE), the major breakdown product of DDT, has been associated with recurrent lower respiratory tract infections (LRTI) in infants. However, epidemiological investigations are limited. Objective To assess the association of prenatal exposure to p,p′-DDE and p,p′-DDT with the occurrence of LRTI in boys from Chiapas, a highly exposed area of Mexico. Methods We analyzed data from 747 singleton boys whose prenatal exposure to p,p′-DDE and p,p′-DDT was determined in maternal serum drawn at delivery (2002–2003). LRTI (i.e., pneumonia, bronchiolitis, and other illness of the bronchi) experienced by the children were reported by their mothers during in-person interviews. The median age of the children when they were last seen was 21.4 months (quartiles 19.1 and 25.3 months). Results Median exposure to p,p′-DDE in this population was higher (2.7 μg/g lipid) than recent U.S. levels (0.20 μg/g). There were 0.19 episodes of LRTI per child-year. After adjusting for potential confounders, children in the highest category of p,p′-DDE (>9.00 μg/g) exposure compared to those in the lowest (≤3.00 μg/g) had an adjusted incidence rate ratio (aIRR) of LRTI of 0.77 (95% confidence interval [CI], 0.41–1.46). The corresponding aIRR for p,p′-DDT (≥2.00 μg/g compared to ≤0.25 μg/g) was 0.65 (95% CI: 0.30–1.39). Conclusion An association of prenatal exposure to p,p′-DDE and p,p′-DDT with LRTI during childhood was not supported in this population with relatively high levels of exposure. PMID:24742723

  1. The implication and potential applications of high-mobility group box 1 protein in breast cancer.

    PubMed

    Sohun, Moonindranath; Shen, Huiling

    2016-06-01

    High-mobility group box 1 protein (HMGB1) is a highly conserved, non-histone and ubiquitous chromosomal protein found enriched in active chromatin forming part of the high mobility group family of proteins and is encoded by the HMGB1 gene (13q12) in human beings. It has various intranuclear and extracellular functions. It plays an important role in the pathogenesis of many diseases including cancer. In 2012, there was approximately 1.67 million new breast cancer cases diagnosed which makes it the second most frequent cancer in the world after lung cancer (25% of all cancers) and the commonest cancer among women. Both pre-clinical and clinical studies have suggested that HMGB1 might be a useful target in the management of breast cancer. This review summarises the structure and functions of HMGB1 and its dual role in carcinogenesis both as a pro-tumorigenic and anti-tumorigenic factor. It also sums up evidence from in vitro and in vivo studies using breast cancer cell lines and samples which demonstrate its influence in radiotherapy, chemotherapy and hormonal therapy in breast cancer. It may have particular importance in HER2 positive and metastatic breast cancer. It might pave the way for new breast cancer treatments through development of novel drugs, use of microRNAs (miRNAs), targeting breast cancer stem cells (CSCs) and breast cancer immunotherapy. It may also play a role in determining breast cancer prognosis. Thus HMGB1 may open up novel avenues in breast cancer management.

  2. The implication and potential applications of high-mobility group box 1 protein in breast cancer

    PubMed Central

    Sohun, Moonindranath

    2016-01-01

    High-mobility group box 1 protein (HMGB1) is a highly conserved, non-histone and ubiquitous chromosomal protein found enriched in active chromatin forming part of the high mobility group family of proteins and is encoded by the HMGB1 gene (13q12) in human beings. It has various intranuclear and extracellular functions. It plays an important role in the pathogenesis of many diseases including cancer. In 2012, there was approximately 1.67 million new breast cancer cases diagnosed which makes it the second most frequent cancer in the world after lung cancer (25% of all cancers) and the commonest cancer among women. Both pre-clinical and clinical studies have suggested that HMGB1 might be a useful target in the management of breast cancer. This review summarises the structure and functions of HMGB1 and its dual role in carcinogenesis both as a pro-tumorigenic and anti-tumorigenic factor. It also sums up evidence from in vitro and in vivo studies using breast cancer cell lines and samples which demonstrate its influence in radiotherapy, chemotherapy and hormonal therapy in breast cancer. It may have particular importance in HER2 positive and metastatic breast cancer. It might pave the way for new breast cancer treatments through development of novel drugs, use of microRNAs (miRNAs), targeting breast cancer stem cells (CSCs) and breast cancer immunotherapy. It may also play a role in determining breast cancer prognosis. Thus HMGB1 may open up novel avenues in breast cancer management. PMID:27386491

  3. The implication and potential applications of high-mobility group box 1 protein in breast cancer.

    PubMed

    Sohun, Moonindranath; Shen, Huiling

    2016-06-01

    High-mobility group box 1 protein (HMGB1) is a highly conserved, non-histone and ubiquitous chromosomal protein found enriched in active chromatin forming part of the high mobility group family of proteins and is encoded by the HMGB1 gene (13q12) in human beings. It has various intranuclear and extracellular functions. It plays an important role in the pathogenesis of many diseases including cancer. In 2012, there was approximately 1.67 million new breast cancer cases diagnosed which makes it the second most frequent cancer in the world after lung cancer (25% of all cancers) and the commonest cancer among women. Both pre-clinical and clinical studies have suggested that HMGB1 might be a useful target in the management of breast cancer. This review summarises the structure and functions of HMGB1 and its dual role in carcinogenesis both as a pro-tumorigenic and anti-tumorigenic factor. It also sums up evidence from in vitro and in vivo studies using breast cancer cell lines and samples which demonstrate its influence in radiotherapy, chemotherapy and hormonal therapy in breast cancer. It may have particular importance in HER2 positive and metastatic breast cancer. It might pave the way for new breast cancer treatments through development of novel drugs, use of microRNAs (miRNAs), targeting breast cancer stem cells (CSCs) and breast cancer immunotherapy. It may also play a role in determining breast cancer prognosis. Thus HMGB1 may open up novel avenues in breast cancer management. PMID:27386491

  4. Teaching high-school Geoscience through a group-based activity: the Geotrivia experiment

    NASA Astrophysics Data System (ADS)

    Bakopoulou, Athanasia

    2015-04-01

    Geotrivia is an educational game which aims at the enhancement of geoscience teaching in secondary education, through an interactive group-based activity. As behavioural teaching methods no longer excite students in a multitask society, new approaches should be implemented to keep up with novel learning methodologies and team-based techniques. Thus, the main aim of the experiment was to come up with an alternative learning process on geology and geography in order to upgrade and attract more students to Geosciences. Geotrivia is based on the techniques of motivation (competition to be the winner) and enjoyable educational time (it is funny to play a game) in terms of team-based student collaboration. Pedagogical aims of Geotrivia consist of team-based work, independency, autonomy and initiative, active participation, student self-evaluation and metacognition. Geotrivia is a card game, consisting of about 150 playing cards, a whistle and an hourglass. Each playing card contains a geology- or geography-related question and the answer to the question is given in the lower part of the card. Class students are divided in about 4 groups of about 5 students each. The aim of each group is to collect as many cards as possible. The hourglass is flipped and a member of the team takes the pack of cards and uses it to ask questions to his team; the other members have to answer as many questions. The team wins a card when they give a correct answer. The game is played at the end of each curriculum unit; a comprehensive version of the game is held at end of the school year. Most -but not all- questions are based on the course syllabus, which deals with the geology and geography of Europe at junior high school level (e.g. what is the cause of high seismicity in Greece?). Accordingly, Geotrivia questions can be adjusted to each country school book of geology - geography at any grade. To evaluate the results of Geotrivia, we used the methodology of pretest and posttest, an

  5. Effect of Solution Focused Group Counseling for High School Students in Order to Struggle with School Burnout

    ERIC Educational Resources Information Center

    Ates, Bünyamin

    2016-01-01

    In this research, the effect of solution focused group counseling upon high school students struggling with school burnout was analyzed. The research was an experimental study in which a pre-test post-test control group random design was used, depending upon the real experimental model. The study group included 30 students that volunteered from…

  6. Long-term exposure to jet fuel: an investigation on occupationally exposed workers with special reference to the nervous system.

    PubMed

    Knave, B; Persson, H E; Goldberg, J M; Westerholm, P

    1976-09-01

    In the present study the results of a neurological and neurophysiological health examination of 29 aircraft factory workers chronically exposed to jet fuel vapors are presented. The exposed subjects were classified into a heavily exposed and a less heavily exposed group. The examination included a standardized clinical neurological examination, measurements of the conduction velocities in the peripheral nerves, and threshold determinations of vibratory sensations in the extremities. All 13 persons examined in the heavily exposed group and 7 of the 16 in the less heavily exposed group stated that they had repeatedly experienced acute effects (dizziness, respiratory tract symptoms, heart palpitations, a feeling of pressure on the chest, nausea, headache) of the jet fuel vapors in the inhaled air. A high rate of symptoms indicative of neurasthenia and psychasthenia and symptoms and signs indicative of polyneuropathy was observed both in the heavily exposed group and in the two groups combined in comparison with reference groups. Considering the presented facts concerning (a) the acute effects on repeated occasions, (b) the high rates of symptoms indicative of neurasthenia and psychasthenia and symptoms and signs indicative of polyneuropathy, and (c) the differences in the observations made between the two groups with varying degrees of exposure to jet fuel, the authors interpreted the results as indicative of a possible effect of long-term exposure to jet fuel on the nervous system.

  7. THE EFFECTS OF A HIGH ANIMAL FAT DIET ON THE INDUCTION OF ABERRANT CRYPT FOCI IN THE COLONS OF MALE F344/N RATS EXPOSED TO TRIHALOMETHANES IN THE DRINKING WATER

    EPA Science Inventory

    The Effects of a High Animal Fat Diet on the Induction of Aberrant Crypt Foci in the Colons of Male F344/N Rats Exposed to Trihalomethanes in the Drinking Water

    Abstract

    Aberrant crypt foci (ACF), identified as the putative precursor lesion in the development of co...

  8. The Group for High Resolution Sea Surface Temperature: Past, Present and Future.

    NASA Astrophysics Data System (ADS)

    Donlon, Craig; Casey, Kenneth; Minnett, Peter; Corlett, Gary

    2014-05-01

    In the last decade, satellite Agencies, science, operational user/producer and Sea Surface Temperature practitioner communities have come together within the Group for High Resolution SST (GHRSST) to create a new framework for generation, delivery and application of improved common format high-resolution (~1-10 km) satellite SST datasets for the benefit of society. The GHRSST data system is a mature, robust, and highly reliable near real time and delayed mode data system known as the GHRSST Regional/Global Task Sharing framework (R/GTS) and has operated in NRT since 2006. It consists of distributed Regional Data Assembly Centers (RDACs) around the world that submit their data to a Global Data Assembly Center (GDAC) maintained at the NASA Jet Propulsion Laboratory Physical Oceanography Distributed Active Archive Center (JPL PO.DAAC), where all the data are available for 30 days. After that they are transferred to the GHRSST Long Term Stewardship and Reanalysis Facility (LTSRF) at the U.S. National Oceanographic Data Center (NODC) for long-term preservation and distribution. The extensive user base includes many operational meteorological services, the scientific community, industry and Government. Since the R/GTS has operated, statistics show over 72,000 users have accessed the R/GTS in NRT, accessing over 100 million files amounting to more than 232 Tb of information. GHRSST has an organisation structure that has both fixed and flexible components allowing it to respond effectively and efficiently to new and emerging challenges. GHRSST has often been cited as a model for other Virtual Communities/Constellations. GHRSST is underpinned by an international Science Team and International Project Office together. Long-standing GHRSST Technical Advisory Groups (TAG) and ad hoc Working Groups (WG) are typically at the "cutting edge" of international SST activities delivering real coordination in space-based Earth observations for societal benefit through the prioritized

  9. Ultra-compact high velocity clouds in the ALFALFA HI survey: Candidate Local Group galaxies?

    NASA Astrophysics Data System (ADS)

    Adams, Elizabeth Ann Kovenz

    The increased sensitivity and spatial resolution of the ALFALFA HI survey has resulted in the detection of ultra-compact high velocity clouds (UCHVCs). These objects are good candidates to represent low mass gas-rich galaxies in the Local Group and Local Volume with stellar populations that are too faint to be detected in extant optical surveys. This idea is referred to as the "minihalo hypothesis". We identify the UCHVCs within the ALFALFA dataset via the use of a 3D matched filtering signal identification algorithm. UCHVCs are selected based on a compact size (< 30'), separation from Galactic HI (|upsilon LSR| > 120 km s-1) and isolation. Within the 40% complete ALFALFA survey (alpha.40), 59 UCHVCs are identified; 19 are in a most-isolated subset and are the best galaxy candidates. Due to the presence of large HVC complexes in the fall sky, most notably the Magellanic Stream, the association of UCHVCs with existing structure cannot be ruled out. In the spring sky, the spatial and kinematic distribution of the UCHVCs is consistent with simulations of dark matter halos within the Local Group. In addition, the HI properties of the UCHVCs (if placed at 1 Mpc) are consistent with both theoretical and observational predictions for low mass gas-rich galaxies. Importantly, the HI properties of the UCHVCs are consistent with those of two recently discovered low mass gas-rich galaxies in the Local Group and Local Volume, Leo T and Leo P. Detailed follow-up observations are key for addressing the minihalo hypothesis. High resolution HI observations can constrain the environment of a UCHVC and offer evidence for a hosting dark matter halo through evidence of rotation support and comparison to theoretical models. Observations of one UCHVC at high resolution (15'') reveal the presence of a clumpy HI distribution, similar to both low mass galaxies and circumgalactic compact HVCs. An extended envelope containing ˜50% of the HI flux is resolved out by the array configuration

  10. Two high-mobility group box domains act together to underwind and kink DNA

    SciTech Connect

    Sánchez-Giraldo, R.; Acosta-Reyes, F. J.; Malarkey, C. S.; Saperas, N.; Churchill, M. E. A.; Campos, J. L.

    2015-06-30

    The crystal structure of HMGB1 box A bound to an unmodified AT-rich DNA fragment is reported at a resolution of 2 Å. A new mode of DNA recognition for HMG box proteins is found in which two box A domains bind in an unusual configuration generating a highly kinked DNA structure. High-mobility group protein 1 (HMGB1) is an essential and ubiquitous DNA architectural factor that influences a myriad of cellular processes. HMGB1 contains two DNA-binding domains, box A and box B, which have little sequence specificity but have remarkable abilities to underwind and bend DNA. Although HMGB1 box A is thought to be responsible for the majority of HMGB1–DNA interactions with pre-bent or kinked DNA, little is known about how it recognizes unmodified DNA. Here, the crystal structure of HMGB1 box A bound to an AT-rich DNA fragment is reported at a resolution of 2 Å. Two box A domains of HMGB1 collaborate in an unusual configuration in which the Phe37 residues of both domains stack together and intercalate the same CG base pair, generating highly kinked DNA. This represents a novel mode of DNA recognition for HMGB proteins and reveals a mechanism by which structure-specific HMG boxes kink linear DNA.

  11. High burden of invasive group A streptococcal disease in the Northern Territory of Australia.

    PubMed

    Boyd, R; Patel, M; Currie, B J; Holt, D C; Harris, T; Krause, V

    2016-04-01

    Although the incidence of invasive group A streptococcal disease in northern Australia is very high, little is known of the regional epidemiology and molecular characteristics. We conducted a case series of Northern Territory residents reported between 2011 and 2013 with Streptococcus pyogenes isolates from a normally sterile site. Of the 128 reported episodes, the incidence was disproportionately high in the Indigenous population at 69·7/100 000 compared to 8·8/100 000 in the non-Indigenous population. Novel to the Northern Territory is the extremely high incidence in haemodialysis patients of 2205·9/100 000 population; and for whom targeted infection control measures could prevent transmission. The incidences in the tropical north and semi-arid Central Australian regions were similar. Case fatality was 8% (10/128) and streptococcal toxic shock syndrome occurred in 14 (11%) episodes. Molecular typing of 82 isolates identified 28 emm types, of which 63 (77%) were represented by four emm clusters. Typing confirmed transmission between infant twins. While the diverse range of emm types presents a challenge for effective coverage by vaccine formulations, the limited number of emm clusters raises optimism should cluster-specific cross-protection prove efficacious. Further studies are required to determine effectiveness of chemoprophylaxis for contacts and to inform public health response. PMID:26364646

  12. High burden of invasive group A streptococcal disease in the Northern Territory of Australia.

    PubMed

    Boyd, R; Patel, M; Currie, B J; Holt, D C; Harris, T; Krause, V

    2016-04-01

    Although the incidence of invasive group A streptococcal disease in northern Australia is very high, little is known of the regional epidemiology and molecular characteristics. We conducted a case series of Northern Territory residents reported between 2011 and 2013 with Streptococcus pyogenes isolates from a normally sterile site. Of the 128 reported episodes, the incidence was disproportionately high in the Indigenous population at 69·7/100 000 compared to 8·8/100 000 in the non-Indigenous population. Novel to the Northern Territory is the extremely high incidence in haemodialysis patients of 2205·9/100 000 population; and for whom targeted infection control measures could prevent transmission. The incidences in the tropical north and semi-arid Central Australian regions were similar. Case fatality was 8% (10/128) and streptococcal toxic shock syndrome occurred in 14 (11%) episodes. Molecular typing of 82 isolates identified 28 emm types, of which 63 (77%) were represented by four emm clusters. Typing confirmed transmission between infant twins. While the diverse range of emm types presents a challenge for effective coverage by vaccine formulations, the limited number of emm clusters raises optimism should cluster-specific cross-protection prove efficacious. Further studies are required to determine effectiveness of chemoprophylaxis for contacts and to inform public health response.

  13. Isolation of a very high molecular weight polylactosamine from an ovarian cyst mucin of blood group

    SciTech Connect

    Wu, A.S.S.; Bush, C.A.

    1986-05-01

    Treatment of a blood group A active ovarian cyst mucin glycoprotein with alkaline borohydride under conditions expected to cleave-O-glycosidically linked carbohydrate chains releases a polysaccharide of average molecular weight 25,000 daltons. It contains no peptide or mannose at the 1% level and carbohydrate analysis gives fuc:galNAc:gal:glcNAc in the ratio of 1:1:2.5:2.5. The /sup 13/C and /sup 1/H NMR spectra show that the polysaccharide has non-reducing terminal side chains of the structure galNAc(..cap alpha..-1 ..-->.. 3)(fuc(..cap alpha..-1 ..-->.. 2)) gal(..beta..-1 ..-->.. 3) glcNAc (i.e. a type 1 chain). Periodate oxidation removes all the fucose and galNAc from the non-reducing terminal but leaves intact the backbone composed of ..beta..-linked gal and glcNAc as would be expected for a polylactosamine. They conclude that this is a high molecular weight polylactosamine which is related to the asparagine linked polylactosamine chains of cell surface glycoproteins which have been implicated in cell differentiation. However, the blood group A polysaccharide from the ovarian cyst mucin is unique in several respects. It has a much larger molecular weight than even the erythroglycan of the red cell membrane protein, band 3, and is linked to the protein by an -O-glycosidic bond rather than the -N-asparagine linkage of the previously known polylactosamines which have a trimannosyl core. Its blood group A side chains are on a type one core rather than type 2 which is found on other polylactosamines.

  14. Nosocomial infections in Brazilian pediatric patients: using a decision tree to identify high mortality groups.

    PubMed

    Lopes, Julia M M; Goulart, Eugenio M A; Siqueira, Arminda L; Fonseca, Inara K; Brito, Marcus V S de; Starling, Carlos E F

    2009-04-01

    Nosocomial infections (NI) are frequent events with potentially lethal outcomes. We identified predictive factors for mortality related to NI and developed an algorithm for predicting that risk in order to improve hospital epidemiology and healthcare quality programs. We made a prospective cohort NI surveillance of all acute-care patients according to the National Nosocomial Infections Surveillance System guidelines since 1992, applying the Centers for Disease Control and Prevention 1988 definitions adapted to a Brazilian pediatric hospital. Thirty-eight deaths considered to be related to NI were analyzed as the outcome variable for 754 patients with NI, whose survival time was taken into consideration. The predictive factors for mortality related to NI (p < 0.05 in the Cox regression model) were: invasive procedures and use of two or more antibiotics. The mean survival time was significantly shorter (p < 0.05 with the Kaplan-Meier method) for patients who suffered invasive procedures and for those who received two or more antibiotics. Applying a tree-structured survival analysis (TSSA), two groups with high mortality rates were identified: one group with time from admission to the first NI less than 11 days, received two or more antibiotics and suffered invasive procedures; the other group had the first NI between 12 and 22 days after admission and was subjected to invasive procedures. The possible modifiable factors to prevent mortality involve invasive devices and antibiotics. The TSSA approach is helpful to identify combinations of predictors and to guide protective actions to be taken in continuous-quality-improvement programs. PMID:20140354

  15. Highly Fluorescent Group 13 Metal Complexes with Cyclic, Aromatic Hydroxamic Acid Ligands

    SciTech Connect

    Seitz, Michael; Moore, Evan G.; Raymond, Kenneth N.

    2008-02-11

    The neutral complexes of two ligands based on the 1-oxo-2-hydroxy-isoquinoline (1,2-HOIQO) motif with group 13 metals (Al, Ga, In) show bright blue-violet luminescence in organic solvents. The corresponding transition can be attributed to ligand-centered singlet emission, characterized by a small Stokes shifts of only a few nm combined with lifetimes in the range between 1-3 ns. The fluorescence efficiency is high, with quantum yields of up to 37% in benzene solution. The crystal structure of one of the indium(III) complexes (trigonal space group R-3, a = b = 13.0384(15) {angstrom}, c = 32.870(8) {angstrom}, ? = {beta} = 90{sup o}, {gamma} = 120{sup o}, V = 4839.3(14) {angstrom}{sup 3}, Z = 6) shows a six-coordinate geometry around the indium center which is close to trigonal-prismatic, with a twist angle between the two trigonal faces of 20.7{sup o}. Time-dependent density functional theory (TD-DFT) calculations (Al and Ga: B3LYP/6-31G(d)); In: B3LYP/LANL2DZ of the fac and mer isomers with one of the two ligands indicate that there is no clear preference for either one of the isomeric forms of the metal complexes. In addition, the metal centers do not have a significant influence on the electronic structure, and as a consequence, on the predominant intraligand optical transitions.

  16. Objects Grouping for Segmentation of Roads Network in High Resolution Images of Urban Areas

    NASA Astrophysics Data System (ADS)

    Maboudi, M.; Amini, J.; Hahn, M.

    2016-06-01

    Updated road databases are required for many purposes such as urban planning, disaster management, car navigation, route planning, traffic management and emergency handling. In the last decade, the improvement in spatial resolution of VHR civilian satellite sensors - as the main source of large scale mapping applications - was so considerable that GSD has become finer than size of common urban objects of interest such as building, trees and road parts. This technological advancement pushed the development of "Object-based Image Analysis (OBIA)" as an alternative to pixel-based image analysis methods. Segmentation as one of the main stages of OBIA provides the image objects on which most of the following processes will be applied. Therefore, the success of an OBIA approach is strongly affected by the segmentation quality. In this paper, we propose a purpose-dependent refinement strategy in order to group road segments in urban areas using maximal similarity based region merging. For investigations with the proposed method, we use high resolution images of some urban sites. The promising results suggest that the proposed approach is applicable in grouping of road segments in urban areas.

  17. Structural phase stability in group IV metals under static high pressure

    SciTech Connect

    Velisavljevic, Nenad; Chesnut, Garry N; Dattelbaum, Dana M; Vohra, Yogesh K; Stemshorn, Andrew

    2009-01-01

    In group IV metals (Ti, Zr, and Hf) room temperature compression leads to a martensitic transformation from a ductile {alpha} to a brittle {omega} phase. {alpha} {yields} {omega} phase boundary decreases to lower pressure at high temperature and can limit the use of group IV metals in industrial applications. There is a large discrepancy in the transition pressure reported in literature, with some of the variation attributed to experimental conditions (i.e. hydrostatic vs. non-hydrostatic). Shear deformation in non-hydrostatic experiments drives {alpha} {yields} {omega} transition and decreases transition pressure. Impurities can also aid or suppress {alpha} {yields} {omega} transition. By performing x-ray diffraction experiments on samples in a diamond anvil cell we show that interstitial impurities, such as C, N, and O can obstruct {alpha} {yields} {omega} transition and stabilize {alpha} phase to higher pressure. We also show that reduction in grain size can also influence {alpha} {yields} {omega} phase boundary and help stabilize {alpha} phase to higher pressure under non-hydrostatic conditions.

  18. Myxobacterial community is a predominant and highly diverse bacterial group in soil niches.

    PubMed

    Zhou, Xiu-wen; Li, Shu-guang; Li, Wei; Jiang, De-ming; Han, Kui; Wu, Zhi-hong; Li, Yue-zhong

    2014-02-01

    Although many molecular ecological surveys have been conducted, there is little concerning the details of specific bacterial groups, resulting in an incomplete understanding of the microorganismal composition and community structures in the environment. Myxobacteria are micropredators that are metabolically active in the soil microbial food web and have typically been considered minority components of soil bacterial communities. In this study, we surveyed the percentage of myxobacteria in a single soil sample via pyrosequencing on combined universal libraries of the V3-V4 and V6-V8 hypervariable regions of the 16S rRNA gene. Surprisingly, myxobacteria accounted for 4.10% of the bacterial community and 7.5% of the total operational taxonomic units at the 3% similarity level in the soil, containing almost all of the cultivated myxobacterial families or genera. To testify the appearance of myxobacteria in soil niches, we retrieved myxobacteria-related 16S rRNA gene sequences of 103 high-throughput sequencing data sets obtained from public databases. The results indicated that myxobacteria-related sequences were among the predominant groups in these data sets accounting for 0.4-4.5% of bacterial communities. The abundance of myxobacterial communities were correlated with site temperature, carbon-to-nitrogen ratio and pH values. Based on these results, we discussed the survival strategies of myxobacterial community in soil.

  19. Cardiovascular effects in viscose rayon workers exposed to carbon disulfide.

    PubMed

    Kotseva, K; Braeckman, L; De Bacquer, D; Bulat, P; Vanhoorne, M

    2001-01-01

    The objectives of this study were to investigate the cardiovascular effects in workers currently exposed to carbon disulfide (CS2) below the threshold limit value (TLV) of 31 mg/m3 and to determine the prevalence of coronary heart disease (CHD) after long-term exposure. 172 men (91 workers exposed to CS2 in a viscose rayon factory and 81 referent workers) were examined using a medical and job history questionnaire, Rose's questionnaire, and electrocardiography at rest, and by measuring blood pressure and serum lipids and lipoproteins. Personal exposures were monitored simultaneously with active sampling and findings were analyzed according to the NIOSH 1600 method. As a result of technical and organizational improvements, personal CS2 exposures were well below the TLV (5.4-13.02 mg/m3). No significant effect of CS2 on blood pressure or lipids (total cholesterol, HDL and LDL cholesterol, triglycerides, and apolipoproteins AI and B) was found, even after allowance for confounding factors. The prevalence of CHD (ECG abnormalities and chest pain) was higher in the viscose rayon workers than in the workers with no exposure but reached statistical significance for men with exposure histories often years and more only (cumulative CS9 index > or = 150 mg/m3, the most highly exposed group). The findings suggest that the coronary risk is increased in workers previously exposed to high CS2 concentrations but not in those exposed to CS2 levels below the current TLV. PMID:11210016

  20. Cardiovascular effects in viscose rayon workers exposed to carbon disulfide.

    PubMed

    Kotseva, K; Braeckman, L; De Bacquer, D; Bulat, P; Vanhoorne, M

    2001-01-01

    The objectives of this study were to investigate the cardiovascular effects in workers currently exposed to carbon disulfide (CS2) below the threshold limit value (TLV) of 31 mg/m3 and to determine the prevalence of coronary heart disease (CHD) after long-term exposure. 172 men (91 workers exposed to CS2 in a viscose rayon factory and 81 referent workers) were examined using a medical and job history questionnaire, Rose's questionnaire, and electrocardiography at rest, and by measuring blood pressure and serum lipids and lipoproteins. Personal exposures were monitored simultaneously with active sampling and findings were analyzed according to the NIOSH 1600 method. As a result of technical and organizational improvements, personal CS2 exposures were well below the TLV (5.4-13.02 mg/m3). No significant effect of CS2 on blood pressure or lipids (total cholesterol, HDL and LDL cholesterol, triglycerides, and apolipoproteins AI and B) was found, even after allowance for confounding factors. The prevalence of CHD (ECG abnormalities and chest pain) was higher in the viscose rayon workers than in the workers with no exposure but reached statistical significance for men with exposure histories often years and more only (cumulative CS9 index > or = 150 mg/m3, the most highly exposed group). The findings suggest that the coronary risk is increased in workers previously exposed to high CS2 concentrations but not in those exposed to CS2 levels below the current TLV.

  1. High mobility group 1 (HMG1) protein in mouse preimplantation embryos.

    PubMed

    Spada, F; Brunet, A; Mercier, Y; Renard, J P; Bianchi, M E; Thompson, E M

    1998-08-01

    High mobility group 1 protein (HMG1) has traditionally been considered a structural component of chromatin, possibly similar in function to histone H1. In fact, at the onset of Xenopus and Drosophila development, HMG1 appears to substitute for histone H1: HMG1 is abundant when histone H1 is absent after the midblastula transition histone H1 largely replaces HMG1. We show that in early mouse embryos the expression patterns of HMG1 and histone H1 are not complementary. Instead, HMG1 content increases after zygotic genome activation at the same time as histone H1. HMG1 does not remain associated to mitotic chromosomes either in embryos or somatic cells. These results argue against a shared structural role for HMG1 and histone H1 in mammalian chromatin.

  2. Zaire program expands to cover high-risk groups in two cities.

    PubMed

    1989-01-01

    This article announces the expansion of Zaire's social marketing program for condoms to high-risk groups in the cities of Goma and Matadi. The program will use proven marketing techniques from Kinshasha, printed materials, and direct marketing to retail outlets, emphasizing hotels, bars, and other areas frequented by prostitutes, migrants, and other travelers. In addition to retail outlets such as pharmacies, 50 taxis will be tested as additional retail sources for Prudence condoms. Once under way, this effort could reach as many as 96,000 people/day. 5 new AIDS information spots are being televised, and an anti-AIDS song and jingle are on the air. Condom social marketing representatives report a 357% increase in condom sales through March, 1989, over 1988, and that products are now available in 85% of Kinshasha pharmacies. Medical center coverage has increased to 14 from 9 zones, while products reach 11 additional cities and 5 interior provinces.

  3. Hydrocarbon group type determination in jet fuels by high performance liquid chromatography

    NASA Technical Reports Server (NTRS)

    Antoine, A. C.

    1977-01-01

    Results are given for the analysis of some jet and diesel fuel samples which were prepared from oil shale and coal syncrudes. Thirty-two samples of varying chemical composition and physical properties were obtained. Hydrocarbon types in these samples were determined by fluorescent indicator adsorption (FIA) analysis, and the results from three laboratories are presented and compared. Recently, rapid high performance liquid chromatography (HPLC) methods have been proposed for hydrocarbon group type analysis, with some suggestion for their use as a replacement of the FIA technique. Two of these methods were used to analyze some of the samples, and these results are also presented and compared. Two samples of petroleum-based Jet A fuel are similarly analyzed.

  4. Zaire program expands to cover high-risk groups in two cities.

    PubMed

    1989-01-01

    This article announces the expansion of Zaire's social marketing program for condoms to high-risk groups in the cities of Goma and Matadi. The program will use proven marketing techniques from Kinshasha, printed materials, and direct marketing to retail outlets, emphasizing hotels, bars, and other areas frequented by prostitutes, migrants, and other travelers. In addition to retail outlets such as pharmacies, 50 taxis will be tested as additional retail sources for Prudence condoms. Once under way, this effort could reach as many as 96,000 people/day. 5 new AIDS information spots are being televised, and an anti-AIDS song and jingle are on the air. Condom social marketing representatives report a 357% increase in condom sales through March, 1989, over 1988, and that products are now available in 85% of Kinshasha pharmacies. Medical center coverage has increased to 14 from 9 zones, while products reach 11 additional cities and 5 interior provinces. PMID:12343426

  5. Leucine supplementation improves adiponectin and total cholesterol concentrations despite the lack of changes in adiposity or glucose homeostasis in rats previously exposed to a high-fat diet

    PubMed Central

    2011-01-01

    Background Studies suggest that leucine supplementation (LS) has a therapeutic potential to prevent obesity and to promote glucose homeostasis. Furthermore, regular physical exercise is a widely accepted strategy for body weight maintenance and also for the prevention of obesity. The aim of this study was to determine the effect of chronic LS alone or combined with endurance training (ET) as potential approaches for reversing the insulin resistance and obesity induced by a high-fat diet (HFD) in rats. Methods Forty-seven rats were randomly divided into two groups. Animals were fed a control diet-low fat (n = 10) or HFD (n = 37). After 15 weeks on HFD, all rats received the control diet-low fat and were randomly divided according to treatment: reference (REF), LS, ET, and LS+ET (n = 7-8 rats per group). After 6 weeks of treatment, the animals were sacrificed and body composition, fat cell volume, and serum concentrations of total cholesterol, HDL-cholesterol, triacylglycerol, glucose, adiponectin, leptin and tumor necrosis factor-alpha (TNF-α) were analyzed. Results At the end of the sixth week of treatment, there was no significant difference in body weight between the REF, LS, ET and LS+ET groups. However, ET increased lean body mass in rats (P = 0.019). In addition, ET was more effective than LS in reducing adiposity (P = 0.019), serum insulin (P = 0.022) and TNF-α (P = 0.044). Conversely, LS increased serum adiponectin (P = 0.021) levels and reduced serum total cholesterol concentration (P = 0.042). Conclusions The results showed that LS had no beneficial effects on insulin sensitivity or adiposity in previously obese rats. On the other hand, LS was effective in increasing adiponectin levels and in reducing total cholesterol concentration. PMID:21899736

  6. Large Group Exposure Treatment: a Feasibility Study in Highly Spider Fearful Individuals

    PubMed Central

    Wannemueller, André; Appelbaum, David; Küppers, Maike; Matten, Amelie; Teismann, Tobias; Adolph, Dirk; Margraf, Jürgen

    2016-01-01

    A large group one-session exposure treatment (LG-OST) based on indirect modeled exposure strategies was carried out to investigate its feasibility and effectiveness in a sample of highly spider fearful individuals (N = 78). The stability of LG-OST-effects was assessed at 8-month follow-up (FU). Furthermore, a second sample (N = 30) of highly spider fearful individuals was treated in a standard, single-person one-session treatment (SP-OST) design to compare LG-OST-effects to a standard spider fear treatment. Participants’ fear of spider was assessed by multiple questionnaires and by a behavioral approach test. The fear assessment took place before and after the respective intervention, and at 8-month FU in LG-OST. Regarding subjective spider fear measures, LG-OST mainly showed medium to large effect sizes, ranging from Cohen’s d = 0.69 to d = 1.21, except for one small effect of d = 0.25. After LG-OST, participants approached the spider closer at post-treatment measures (d = 1.18). LG-OST-effects remained stable during the 8-month FU-interval. However, SP-OST-effects proved superior in most measures. An LG-OST-protocol provided evidence for feasibility and efficiency. The effects of LG-OST were equal to those of indirect modeled exposure strategies, carried out in single-settings. LG-OST may represent a useful tool in future phobia-treatment, especially if it can match the effects of single-setting OST, e.g., by including more direct exposure elements in future large group attempts. PMID:27555830

  7. Coordinative Properties of Highly Fluorinated Solvents with Amino and Ether Groups

    PubMed Central

    Boswell, Paul G.; Lugert, Elizabeth C.; Rábai, József; Amin, Elizabeth A.; Bühlmann, Philippe

    2008-01-01

    In spite of the widespread use of perfluorinated solvents with amino and ether groups in a variety of application fields, the coordinative properties of these compounds are poorly known. It is generally assumed that the electron withdrawing perfluorinated moieties render these functional groups rather inert, but little is known quantitatively about the extent of their inertness. This paper reports on the interactions between inorganic monocations and perfluorotripentylamine and 2H-perfluoro-5,8,11-trimethyl-3,6,9,12-tetraoxapentadecane, as determined with fluorous liquid-membrane cation-selective electrodes doped with tetrakis[3,5-bis(perfluorohexyl)phenyl]borate salts. The amine does not undergo measurable association with any ion tested, and its formal pKa is shown to be smaller than -0.5. This is consistent with the nearly planar structure of the amine at its nitrogen center, as obtained with density functional theory calculations. The tetraether interacts very weakly with Na+ and Li+. Assuming 1:1 stoichiometry, formal association constants were determined to be 2.3 and 1.5 M-1, respectively. This disproves an earlier proposition that the Lewis base character in such compounds may be non-existent. Due to the extremely low polarity of fluorous solvents and the resulting high extent of ion pair formation, a fluorophilic electrolyte salt with perfluoroalkyl substituents on both the cation and the anion had to be developed for these experiments. In its pure form, this first fluorophilic electrolyte salt is an ionic liquid with a glass transition temperature, Tg, of -18.5 °C. Interestingly, the molar conductivity of solutions of this salt increases very steeply in the high concentration range, making it a particularly effective electrolyte salt. PMID:16316244

  8. Large Group Exposure Treatment: a Feasibility Study in Highly Spider Fearful Individuals.

    PubMed

    Wannemueller, André; Appelbaum, David; Küppers, Maike; Matten, Amelie; Teismann, Tobias; Adolph, Dirk; Margraf, Jürgen

    2016-01-01

    A large group one-session exposure treatment (LG-OST) based on indirect modeled exposure strategies was carried out to investigate its feasibility and effectiveness in a sample of highly spider fearful individuals (N = 78). The stability of LG-OST-effects was assessed at 8-month follow-up (FU). Furthermore, a second sample (N = 30) of highly spider fearful individuals was treated in a standard, single-person one-session treatment (SP-OST) design to compare LG-OST-effects to a standard spider fear treatment. Participants' fear of spider was assessed by multiple questionnaires and by a behavioral approach test. The fear assessment took place before and after the respective intervention, and at 8-month FU in LG-OST. Regarding subjective spider fear measures, LG-OST mainly showed medium to large effect sizes, ranging from Cohen's d = 0.69 to d = 1.21, except for one small effect of d = 0.25. After LG-OST, participants approached the spider closer at post-treatment measures (d = 1.18). LG-OST-effects remained stable during the 8-month FU-interval. However, SP-OST-effects proved superior in most measures. An LG-OST-protocol provided evidence for feasibility and efficiency. The effects of LG-OST were equal to those of indirect modeled exposure strategies, carried out in single-settings. LG-OST may represent a useful tool in future phobia-treatment, especially if it can match the effects of single-setting OST, e.g., by including more direct exposure elements in future large group attempts. PMID:27555830

  9. Large Group Exposure Treatment: a Feasibility Study in Highly Spider Fearful Individuals.

    PubMed

    Wannemueller, André; Appelbaum, David; Küppers, Maike; Matten, Amelie; Teismann, Tobias; Adolph, Dirk; Margraf, Jürgen

    2016-01-01

    A large group one-session exposure treatment (LG-OST) based on indirect modeled exposure strategies was carried out to investigate its feasibility and effectiveness in a sample of highly spider fearful individuals (N = 78). The stability of LG-OST-effects was assessed at 8-month follow-up (FU). Furthermore, a second sample (N = 30) of highly spider fearful individuals was treated in a standard, single-person one-session treatment (SP-OST) design to compare LG-OST-effects to a standard spider fear treatment. Participants' fear of spider was assessed by multiple questionnaires and by a behavioral approach test. The fear assessment took place before and after the respective intervention, and at 8-month FU in LG-OST. Regarding subjective spider fear measures, LG-OST mainly showed medium to large effect sizes, ranging from Cohen's d = 0.69 to d = 1.21, except for one small effect of d = 0.25. After LG-OST, participants approached the spider closer at post-treatment measures (d = 1.18). LG-OST-effects remained stable during the 8-month FU-interval. However, SP-OST-effects proved superior in most measures. An LG-OST-protocol provided evidence for feasibility and efficiency. The effects of LG-OST were equal to those of indirect modeled exposure strategies, carried out in single-settings. LG-OST may represent a useful tool in future phobia-treatment, especially if it can match the effects of single-setting OST, e.g., by including more direct exposure elements in future large group attempts.

  10. Pathogenesis of highly virulent African swine fever virus in domestic pigs exposed via intraoropharyngeal, intranasopharyngeal, and intramuscular inoculation, and by direct contact with infected pigs.

    PubMed

    Howey, Erin B; O'Donnell, Vivian; de Carvalho Ferreira, Helena C; Borca, Manuel V; Arzt, Jonathan

    2013-12-26

    To investigate the pathogenesis of African swine fever virus (ASFV), domestic pigs (n=18) were challenged with a range (10(2)-10(6) 50% hemadsorbing doses (HAD50)) of the highly virulent ASFV-Malawi strain by inoculation via the intraoropharyngeal (IOP), intranasopharyngeal (INP), or intramuscular (IM) routes. A subsequent contact challenge experiment was performed in which six IOP-inoculated donor pigs were allowed to have direct contact (DC) with six naïve pigs for exposure times that varied from 24 to 72 h. All challenge routes resulted in clinical progression and postmortem lesions similar to those previously described in experimental and natural infection. The onset of clinical signs occurred between 1 and 7 days post inoculation (dpi) and included pyrexia with variable progression to obtundation, hematochezia, melena, moribundity and death with a duration of 4-11 days. Viremia was first detected between 4 and 5 dpi in all inoculation groups whereas ASFV shedding from the nasal cavity and tonsil was first detected at 3-9 dpi. IM and DC were the most consistent modes of infection, with 12/12 (100%) of pigs challenged by these routes becoming infected. Several clinical and virological parameters were significantly different between IM and DC groups indicating dissimilarity between these modes of infection. Amongst the simulated natural routes, INP inoculation resulted in the most consistent progression of disease across the widest range of doses whilst preserving simulation of natural exposure and therefore may provide a superior system for pathogenesis and vaccine efficacy investigation.

  11. Space allowance and high fiber diet impact performance and behavior of group-kept gestating sows.

    PubMed

    DeDecker, A E; Hanson, A R; Walker, P M; Salak-Johnson, J L

    2014-04-01

    Identifying and optimizing housing and management systems that improve the well-being of the gestating sow is essential to sustaining animal agriculture. Therefore, the impact of 2 floor-space allowances and a high-fiber gestation diet on dry group-housed sows were evaluated using multiple measures of well-being. Groups of 10 multiparous sows/pen (n = 221) were assigned randomly to treatments in a 2 × 2 factorial arrangement to either a corn-soybean meal diet (CTL) or corn-soybean meal diet supplemented with soybean hulls and wheat middlings (FBR), and floor-space allowance of either 1.7 or 2.3 m(2)/sow. Sow BW, backfat (BF), and body condition score (BCS) were all recorded on d 34, 65, 90, and 110 of gestation, whereas skin lesions were scored on d 34, every 2 d for the first 2-wk postmixing, and then biweekly throughout gestation. Blood sample was collected only on d 34 for cortisol (baseline), and samples were collected on d 90 of gestation for other measures including cortisol. Behavior was registered on multiple days throughout gestation. Sows fed FBR and kept at 1.7 m(2) produced heavier litter and weaning weights and greater number of piglets born alive, compared to sows fed FBR but kept at 2.3 m(2) of floor space (diet × floor space, P ≤ 0.04). Sows fed FBR and kept at 1.7 m(2) performed fewer oral-nasal-facial and sham-chew behaviors than sows fed CTL and kept at the same floor space (diet × floor space, P ≤ 0.044). Sows kept at 1.7 m(2) of floor space had a greater (P < 0.05) total lesion severity score than sows kept at 2.3 m(2)/sow, and vulva lesion scores were more (P < 0.02) severe among CTL-fed sows than FBR-fed sows. Parities 2 and 3 sows fed FBR and kept at 1.7 m(2) of floor space were heavier (P < 0.001) than sows fed the same diet but kept at 2.3 m(2). These results indicate that keeping small groups of pregnant sows at a minimum floor-space allowance of 1.7 m(2)/sow and floor feeding these sows a high-fiber diet can improve short-term sow

  12. High Mobility Group Box Protein-1 Correlates with Renal Function in Chronic Kidney Disease (CKD)

    PubMed Central

    Bruchfeld, Annette; Qureshi, Abdul Rashid; Lindholm, Bengt; Barany, Peter; Yang, LiHong; Stenvinkel, Peter; Tracey, Kevin J

    2008-01-01

    Chronic kidney disease (CKD) is associated with inflammation and malnutrition and carries a markedly increased risk of cardiovascular disease (CVD). High Mobility Group Box Protein-1 (HMGB-1) is a 30-kDa nuclear and cytosolic protein known as a transcription and growth factor, recently identified as a proinflammatory mediator of tissue injury. Recent data implicates HMGB-1 in endotoxin lethality, rheumatoid arthritis, and atherosclerosis. The aim of this post-hoc, cross-sectional study was to determine whether HMGB-1 serum levels are elevated in CKD patients. The study groups were categorized as follows: 110 patients starting dialysis defined as CKD 5; 67 patients with moderately to severely reduced renal function or CKD 3–4; and 48 healthy controls. High-sensitivity C-reactive-protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor (TNF), serum-albumin (S-albumin), hemoglobin A1c (HbA1c), hemoglobin, subjective global nutritional assessment (SGA), and glomerular filtration rate (GFR) were analyzed. Kruskal-Wallis test was used to compare groups and Spearman’s rank correlation test was used for continuous variables. HMGB-1, measured by Western blot, was significantly (P < 0.001) elevated in CKD 5 (146.7 ± 58.6 ng/mL) and CKD 3–4 (85.6 ± 31.8) compared with controls (10.9 ± 10.5). HMGB-1 levels were correlated positively with TNF (Rho = 0.52; P < 0.001), hs-CRP (Rho = 0.38; P < 0.001), IL-6 (Rho = 0.30; P < 0.001), HbA1c (Rho = 0.14; P = 0.02) and SGA (Rho = 0.21; P = 0.002) and negatively correlated with GFR (Rho = –0.69; P = 0.0001), Hb (Rho = –0.60; P < 0.001), S-albumin (Rho = –0.31; P < 0.001). The current study has revealed that HMGB-1 is elevated significantly in CKD patients and correlates with GFR as well as markers of inflammation and malnutrition. Future studies may delineate whether HMGB-1 is also a marker of disease activity and severity as well as a predictor of outcome in CKD. PMID:18317568

  13. Holography as a highly efficient renormalization group flow. I. Rephrasing gravity

    NASA Astrophysics Data System (ADS)

    Behr, Nicolas; Kuperstein, Stanislav; Mukhopadhyay, Ayan

    2016-07-01

    We investigate how the holographic correspondence can be reformulated as a generalization of Wilsonian renormalization group (RG) flow in a strongly interacting large-N quantum field theory. We first define a highly efficient RG flow as one in which the Ward identities related to local conservation of energy, momentum and charges preserve the same form at each scale. To achieve this, it is necessary to redefine the background metric and external sources at each scale as functionals of the effective single-trace operators. These redefinitions also absorb the contributions of the multitrace operators to these effective Ward identities. Thus, the background metric and external sources become effectively dynamical, reproducing the dual classical gravity equations in one higher dimension. Here, we focus on reconstructing the pure gravity sector as a highly efficient RG flow of the energy-momentum tensor operator, leaving the explicit constructive field theory approach for generating such RG flows to the second part of the work. We show that special symmetries of the highly efficient RG flows carry information through which we can decode the gauge fixing of bulk diffeomorphisms in the corresponding gravity equations. We also show that the highly efficient RG flow which reproduces a given classical gravity theory in a given gauge is unique provided the endpoint can be transformed to a nonrelativistic fixed point with a finite number of parameters under a universal rescaling. The results obtained here are used in the second part of this work, where we do an explicit field-theoretic construction of the RG flow and obtain the dual classical gravity theory.

  14. HCV epidemiology in high-risk groups and the risk of reinfection.

    PubMed

    Midgard, Håvard; Weir, Amanda; Palmateer, Norah; Lo Re, Vincent; Pineda, Juan A; Macías, Juan; Dalgard, Olav

    2016-10-01

    Injecting risk behaviours among people who inject drugs (PWID) and high-risk sexual practices among men who have sex with men (MSM) are important routes of hepatitis C virus (HCV) transmission. Current direct-acting antiviral treatment offers unique opportunities for reductions in HCV-related liver disease burden and epidemic control in high-risk groups, but these prospects could be counteracted by HCV reinfection due to on-going risk behaviours after successful treatment. Based on existing data from small and heterogeneous studies of interferon-based treatment, the incidence of reinfection after sustained virological response range from 2-6/100 person years among PWID to 10-15/100 person years among human immunodeficiency virus-infected MSM. These differences mainly reflect heterogeneity in study populations with regards to risk behaviours, but also reflect variations in study designs and applied virological methods. Increasing levels of reinfection are to be expected as we enter the interferon-free treatment era. Individual- and population-level efforts to address and prevent reinfection should therefore be undertaken when providing HCV care for people with on-going risk behaviour. Constructive strategies include acknowledgement, education and counselling, harm reduction optimization, scaled-up treatment including treatment of injecting networks, post-treatment screening, and rapid retreatment of reinfections. PMID:27641987

  15. Extracellular High-Mobility Group Box 1 Protein (HMGB1) as a Mediator of Persistent Pain

    PubMed Central

    Agalave, Nilesh M; Svensson, Camilla I

    2014-01-01

    Although originally described as a highly conserved nuclear protein, high-mobility group box 1 protein (HMGB1) has emerged as a danger-associated molecular pattern molecule protein (DAMP) and is a mediator of innate and specific immune responses. HMGB1 is passively or actively released in response to infection, injury and cellular stress, providing chemotactic and cytokine-like functions in the extracellular environment, where it interacts with receptors such as receptor for advanced glycation end products (RAGE) and several Toll-like receptors (TLRs). Although HMGB1 was first revealed as a key mediator of sepsis, it also contributes to a number of other conditions and disease processes. Chronic pain arises as a direct consequence of injury, inflammation or diseases affecting the somatosensory system and can be devastating for the affected patients. Emerging data indicate that HMGB1 is also involved in the pathology of persistent pain. Here, we give an overview of HMGB1 as a proinflammatory mediator, focusing particularly on the role of HMGB1 in the induction and maintenance of hypersensitivity in experimental models of pain and discuss the therapeutic potential of targeting HMGB1 in conditions of chronic pain. PMID:25222915

  16. Screening for celiac disease in the general population and in high-risk groups

    PubMed Central

    Card, Timothy R; Kaukinen, Katri; Bai, Julio; Zingone, Fabiana; Sanders, David S; Murray, Joseph A

    2015-01-01

    Background Celiac disease (CD) occurs in approximately 1% of the Western population. It is a lifelong disorder that is associated with impaired quality of life (QOL) and an excessive risk of comorbidity and death. Objectives To review the literature on screening for CD in relation to the current World Health Organization (WHO) criteria for mass screening. Methods We performed a PubMed search to identify indexed papers on CD screening with a publication date from 1900 until 1 June 2014. When we deemed an abstract relevant, we read the corresponding paper in detail. Results CD fulfills several WHO criteria for mass screening (high prevalence, available treatment and difficult clinical detection), but it has not yet been established that treatment of asymptomatic CD may reduce the excessive risk of severe complications, leading to higher QOL nor that it is cost-effective. Conclusions Current evidence is not sufficient to support mass screening for CD, but active case-finding may be appropriate, as we recognize that most patients with CD will still be missed by this strategy. Although proof of benefit is still lacking, screening for CD may be appropriate in high-risk groups. PMID:25922671

  17. The role of high mobility group box chromosomal protein 1 in rheumatoid arthritis.

    PubMed

    Chen, Yu; Sun, Wei; Gao, Rongfen; Su, Yuying; Umehara, Hisanori; Dong, Lingli; Gong, Feili

    2013-10-01

    High mobility group box chromosomal protein 1 (HMGB1) is a ubiquitous highly conserved single polypeptide in all mammal eukaryotic cells. HMGB1 exists mainly within the nucleus and acts as a DNA chaperone. When passively released from necrotic cells or actively secreted into the extracellular milieu in response to appropriate signal stimulation, HMGB1 binds to related cell signal transduction receptors, such as RAGE, TLR2, TLR4 and TLR9, and becomes a proinflammatory cytokine that participates in the development and progression of many diseases, such as arthritis, acute lung injury, graft rejection immune response, ischaemia reperfusion injury and autoimmune liver damage. Only a small amount of HMGB1 release occurs during apoptosis, which undergoes oxidative modification on Cys106 and delivers tolerogenic signals to suppress immune activity. This review focuses on the important role of HMGB1 in the pathogenesis of RA, mainly manifested as the aberrant expression of HMGB1 in the serum, SF and synovial tissues; overexpression of signal transduction receptors; abnormal regulation of osteoclastogenesis and bone remodelling leading to the destruction of cartilage and bones. Intervention with HMGB1 may ameliorate the pathogenic conditions and attenuate disease progression of RA. Therefore administration of an HMGB1 inhibitor may represent a promising clinical approach for the treatment of RA.

  18. Endoscopic Gastric Cancer Screening and Surveillance in High-Risk Groups

    PubMed Central

    2014-01-01

    Gastric cancer remains a major cancer problem world-wide and future incidence will likely increase due to rapidly aging population demographics. Population-based screening is being undertaken in Korea and Japan, where gastric cancer incidence rates are high, and seems to be effective in reducing mortality from gastric cancer. However, such strategies are difficult to implement in countries with a low incidence or limited resources. Thus, screening strategies should be directed towards high-risk population subgroups. Gastric cancer has a relatively long mean sojourn time, and prognosis of early-stage disease is excellent. In general population, screening at 2-year interval in Korea seems to be effective for early-stage diagnosis. In subjects with atrophic gastritis or intestinal metaplasia, surveillance is recommended at 1 to 3 years intervals according to European and Japanese recommendation. Screening intervals for family members with sporadic gastric cancer has not yet been adequately evaluated, but 1-year interval is recommended for hereditary diffuse gastric cancer family-members. Gastric cancer patients treated by endoscopic resection are the highest-risk group, and 1-year interval surveillance can detect most metachronous gastric cancers at an early stage. Future gastric cancer surveillance strategies using endoscopy should be guided by risk-stratification assessment, and further refinement of optimal surveillance intervals is needed. PMID:25505714

  19. High-mobility group box 1 protein and its role in severe acute pancreatitis.

    PubMed

    Shen, Xiao; Li, Wei-Qin

    2015-02-01

    The high mobility group box 1 (HMGB1), which belongs to the subfamily of HMG-1/-2, is a highly conserved single peptide chain consisting of 215 amino acid residues with a molecular weight of approximately 24894 Da. HMGB1 is a ubiquitous nuclear protein in mammals and plays a vital role in inflammatory diseases. Acute pancreatitis is one of the most common causes of acute abdominal pain with a poor prognosis. Acute pancreatitis is an acute inflammatory process of the pancreas (duration of less than six months), for which the severe form is called severe acute pancreatitis (SAP). More and more studies have shown that HMGB1 has a bidirectional effect in the pathogenesis of SAP. Extracellular HMGB1 can aggravate the pancreatic inflammatory process, whereas intracellular HMGB1 has a protective effect against pancreatitis. The mechanism of HMGB1 is multiple, mainly through the nuclear factor-κB pathway. Receptors for advanced glycation end-products and toll-like receptors (TLR), especially TLR-2 and TLR-4, are two major types of receptors mediating the inflammatory process triggered by HMGB1 and may be also the main mediators in the pathogenesis of SAP. HMGB1 inhibitors, such as ethyl pyruvate, pyrrolidine dithiocarbamate and Scolopendra subspinipes mutilans, can decrease the level of extracellular HMGB1 and are the promising targets in the treatment of SAP.

  20. HCV epidemiology in high-risk groups and the risk of reinfection.

    PubMed

    Midgard, Håvard; Weir, Amanda; Palmateer, Norah; Lo Re, Vincent; Pineda, Juan A; Macías, Juan; Dalgard, Olav

    2016-10-01

    Injecting risk behaviours among people who inject drugs (PWID) and high-risk sexual practices among men who have sex with men (MSM) are important routes of hepatitis C virus (HCV) transmission. Current direct-acting antiviral treatment offers unique opportunities for reductions in HCV-related liver disease burden and epidemic control in high-risk groups, but these prospects could be counteracted by HCV reinfection due to on-going risk behaviours after successful treatment. Based on existing data from small and heterogeneous studies of interferon-based treatment, the incidence of reinfection after sustained virological response range from 2-6/100 person years among PWID to 10-15/100 person years among human immunodeficiency virus-infected MSM. These differences mainly reflect heterogeneity in study populations with regards to risk behaviours, but also reflect variations in study designs and applied virological methods. Increasing levels of reinfection are to be expected as we enter the interferon-free treatment era. Individual- and population-level efforts to address and prevent reinfection should therefore be undertaken when providing HCV care for people with on-going risk behaviour. Constructive strategies include acknowledgement, education and counselling, harm reduction optimization, scaled-up treatment including treatment of injecting networks, post-treatment screening, and rapid retreatment of reinfections.

  1. Increased frequency of CD4-8-T cells bearing T-cell receptor alpha beta chains in peripheral blood of atomic bomb survivors exposed to high doses.

    PubMed

    Kusunoki, Y; Kyoizumi, S; Hirai, Y; Fujita, S; Akiyama, M

    1994-07-01

    A rare T-cell subpopulation, CD4-8- alpha beta T cells, may be differentiated through a pathway (or pathways) different from the pathway(s) of conventional CD4+ or CD8+ T cells. In the present study, the frequencies of CD4-8-T cells in peripheral-blood alpha beta T cells in 409 atomic bomb survivors (160 estimated to have been exposed to 1.5 Gy or more and 249 controls) were determined to investigate late effects of radiation on the composition of human T-cell subpopulations. The frequency of CD4-8- alpha beta T-cell decreased significantly with the subject's age and was higher in females than males. A significant increase in the frequency was found in the survivors exposed to more than 1.5 Gy, suggesting that the previous radiation exposure altered differentiation and development of T cells.

  2. Effect of exposing two commercial manufacturers' second surface silver/glass mirrors to elevated temperature, mechanical loading, and high-humidity environments

    SciTech Connect

    Dake, L.S.; Lind, M.A.

    1982-04-01

    A preliminary examination of the effect of three accelerated exposure parameters on second surface silver/glass mirrors was performed. The variables studied were temperature (elevated and sub-zero), humidity and mechanical loading. One test consisted of exposing mirror coupons to dry heat (80/sup 0/C) and heat plus water vapor (80/sup 0/C, approx. 100% RH) environments. Another test consisted of subjecting mechanically loaded mirror strips to sub-zero temperature (-20/sup 0/C), dry heat (80/sup 0/C), and heat plus water vapor. Samples were evaluated qualitatively using dark field microscopy (1X and 100X). Quantitative determination of the effects of exposure testing on the mirrors was done with spectrophotometer spectral hemispherical and diffuse reflectance measurements. Degradation that was progressive with time was observed for mirrors exposed to dry heat and heat plus water vapor. The degradation did not have the same visual appearance for the two environments. Mechanical loading at -20/sup 0/C produced no degradation after three months' exposure time. Mechanical loading in dry heat and heat plus water vapor environments resulted in mirror degradation that was the same as that found in unloaded mirrors exposed to the same temperature and humidity. These preliminary tests indicate that the dry heat and heat plus water vapor accelerated tests may provide useful information about mirror degradation, while the mechanical load tests do not. The microscopy and spectrophotometer reflectance measurements were both useful techniques for determining the extent of degradation.

  3. Amphidynamic crystals of a steroidal bicyclo[2.2.2]octane rotor: a high symmetry group that rotates faster than smaller methyl and methoxy groups.

    PubMed

    Rodríguez-Molina, Braulio; Pérez-Estrada, Salvador; Garcia-Garibay, Miguel A

    2013-07-17

    The synthesis, crystallization, single crystal X-ray structure, and solid state dynamics of molecular rotor 3 provided with a high symmetry order and relatively cylindrical bicyclo[2.2.2]octane (BCO) rotator linked to mestranol fragments were investigated in this work. By use of solid state (13)C NMR, three rotating fragments were identified within the molecule: the BCO, the C19 methoxy and the C18 methyl groups. To determine the dynamics of the BCO group in crystals of 3 by variable temperature (1)H spin-lattice relaxation (VT (1)H T1), we determined the (1)H T1 contributions from the methoxy group C19 by carrying out measurements with the methoxy-deuterated isotopologue rotor 3-d6. The contributions from the quaternary methyl group C18 were estimated by considering the differences between the VT (1)H T1 of mestranol 8 and methoxy-deuterated mestranol 8-d3. From these studies it was determined that the BCO rotator in 3 has an activation energy of only 1.15 kcal mol(-1), with a barrier for site exchange that is smaller than those of methyl (E(a) = 1.35 kcal mol(-1)) and methoxy groups (E(a) = 1.92 kcal mol(-1)), despite their smaller moments of inertia and surface areas.

  4. The Local Group as a time machine: studying the high-redshift Universe with nearby galaxies

    NASA Astrophysics Data System (ADS)

    Boylan-Kolchin, Michael; Weisz, Daniel R.; Johnson, Benjamin D.; Bullock, James S.; Conroy, Charlie; Fitts, Alex

    2015-10-01

    We infer the UV luminosities of Local Group galaxies at early cosmic times (z ˜ 2 and z ˜ 7) by combining stellar population synthesis modelling with star formation histories derived from deep colour-magnitude diagrams constructed from Hubble Space Telescope (HST) observations. Our analysis provides a basis for understanding high-z galaxies - including those that may be unobservable even with the James Webb Space Telescope (JWST) - in the context of familiar, well-studied objects in the very low-z Universe. We find that, at the epoch of reionization, all Local Group dwarfs were less luminous than the faintest galaxies detectable in deep HST observations of blank fields. We predict that JWST will observe z ˜ 7 progenitors of galaxies similar to the Large Magellanic Cloud today; however, the HST Frontier Fields initiative may already be observing such galaxies, highlighting the power of gravitational lensing. Consensus reionization models require an extrapolation of the observed blank-field luminosity function (LF) at z ≈ 7 by at least 2 orders of magnitude in order to maintain reionization. This scenario requires the progenitors of the Fornax and Sagittarius dwarf spheroidal galaxies to be contributors to the ionizing background at z ˜ 7. Combined with numerical simulations, our results argue for a break in the UV LF from a faint-end slope of α ˜ -2 at MUV ≲ -13 to α ˜ -1.2 at lower luminosities. Applied to photometric samples at lower redshifts, our analysis suggests that HST observations in lensing fields at z ˜ 2 are capable of probing galaxies with luminosities comparable to the expected progenitor of Fornax.

  5. High affinity group III mGluRs regulate mossy fiber input to CA3 interneurons

    PubMed Central

    Cosgrove, Kathleen E.; Meriney, Stephen D.; Barrionuevo, Germán

    2010-01-01

    Stratum lacunosum-moleculare interneurons (L-Mi) in hippocampal area CA3 target the apical dendrite of pyramidal cells providing feedforward inhibition. Here we report that selective activation of group III metabotropic glutamate receptors (mGluRs) 4/8 with L-(+)-2-amino-4-phosphnobytyric acid (L-AP4; 10 μM) decreased the probability of glutamate release from the mossy fiber (MF) terminals synapsing onto L-Mi. Consistent with this interpretation, application of L-AP4 in the presence of 3 mM strontium decreased the frequency of asynchronous MF EPSCs in L-Mi. Furthermore, the dose response curve showed that L-AP4 at 400 μM produced no further decrease in MF EPSC amplitude compared to 20 μM L-AP4, indicating the lack of mGluRs 7 at these MF terminals. We also found that one mechanism of mGluRs 4/8-mediated inhibition of release is linked to N-type voltage gated calcium channels at MF terminals. Application of the group III mGluR antagonist MSOP (100 μM) demonstrated that mGluRs 4/8 are neither tonically active nor activated by low and moderate frequencies of activity. However, trains of stimuli to the MF at 20 and 40Hz delivered during the application of MSOP revealed a relief of inhibition of transmitter release and an increase in the overall probability of action potential firing in the postsynaptic L-Mi. Interestingly, the time to first action potential was significantly shorter in the presence of MSOP, indicating that mGluR 4/8 activation delays L-Mi firing in response to MF activity. Taken together, our data demonstrate that the timing and probability of action potentials in L-Mi evoked by MF synaptic input is regulated by the activation of presynaptic high affinity group III mGluRs. PMID:20824730

  6. Development of group IV molecular catalysts for high temperature ethylene-α-olefin copolymerization reactions.

    PubMed

    Klosin, Jerzy; Fontaine, Philip P; Figueroa, Ruth

    2015-07-21

    This Account describes our research related to the development of molecular catalysts for solution phase olefin polymerization. Specifically, a series of constrained geometry and nonmetallocene (imino-amido-type) complexes were developed for high temperature olefin polymerization reactions. We have discovered many highly active catalysts that are capable of operating at temperatures above 120 °C and producing copolymers with a useful range of molecular weights (from medium to ultrahigh depending on precatalyst identity and polymerization conditions) and α-olefin incorporation capability. Constrained geometry catalysts (CGCs) exhibit very high activities and are capable of producing a variety of copolymers including ethylene-propylene and ethylene-1-octene copolymers at high reactor temperatures. Importantly, CGCs have much higher reactivity toward α-olefins than classical Ziegler-Natta catalysts, thus allowing for the production of copolymers with any desired level of comonomer. In search of catalysts with improved performance, we discovered 3-amino-substituted indenyl-based CGCs that exhibit the highest activity and produce copolymers with the highest molecular weight within this family of catalysts. Phenanthrenyl-based CGCs were found to be outstanding catalysts for the effective production of high styrene content ethylene-styrene copolymers under industrially relevant conditions. In contrast to CGC ligands, imino-amido-type ligands are bidentate and monoionic, leading to the use of trialkyl group IV precatalysts. The thermal instability of imino-amido complexes was addressed by the development of imino-enamido and amidoquinoline complexes, which are not only thermally very robust, but also produce copolymers with higher molecular weights, and exhibit improved α-olefin incorporation. Imido-amido and imino-enamido catalysts undergo facile chain transfer reactions with metal alkyls, as evidenced by a sharp decrease in polymer molecular weight when the

  7. Development of group IV molecular catalysts for high temperature ethylene-α-olefin copolymerization reactions.

    PubMed

    Klosin, Jerzy; Fontaine, Philip P; Figueroa, Ruth

    2015-07-21

    This Account describes our research relat