Sample records for earlier studies conducted

  1. Childhood hair product use and earlier age at menarche in a racially diverse study population: a pilot study.

    PubMed

    James-Todd, Tamarra; Terry, Mary Beth; Rich-Edwards, Janet; Deierlein, Andrea; Senie, Ruby

    2011-06-01

    Previous studies suggest that hair products containing endocrine disrupting chemicals could alter puberty. We evaluated the association between childhood hair product use and age at menarche in a racially diverse study population. We recruited 300 African-American, African-Caribbean, Hispanic, and white women from the New York City metropolitan area who were between 18-77 years of age. Data were collected retrospectively on hair oil, lotion, leave-in conditioner, perm, and other types of hair products used before age 13. Recalled age at menarche ranged from 8 to 19 years. We used multivariable binomial regression to evaluate the association between hair product use and age at menarche (<12 vs. ≥12), adjusting for potential confounders. African-Americans were more likely to use hair products and reached menarche earlier than other racial/ethnic groups. Women reporting childhood hair oil use had a risk ratio of 1.4 (95% confidence interval [CI]: 1.1-1.9) for earlier menarche, adjusting for race/ethnicity and year of birth. Hair perm users had an increased risk for earlier menarche (adjusted risk ratio = 1.4, 95% CI: 1.1-1.8). Other types of hair products assessed in this study were not associated with earlier menarche. Childhood hair oil and perm use were associated with earlier menarche. If replicated, these results suggest that hair product use may be important to measure in evaluating earlier age at menarche. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Earlier snowmelt and warming lead to earlier but not necessarily more plant growth.

    PubMed

    Livensperger, Carolyn; Steltzer, Heidi; Darrouzet-Nardi, Anthony; Sullivan, Patrick F; Wallenstein, Matthew; Weintraub, Michael N

    2016-01-01

    Climate change over the past ∼50 years has resulted in earlier occurrence of plant life-cycle events for many species. Across temperate, boreal and polar latitudes, earlier seasonal warming is considered the key mechanism leading to earlier leaf expansion and growth. Yet, in seasonally snow-covered ecosystems, the timing of spring plant growth may also be cued by snowmelt, which may occur earlier in a warmer climate. Multiple environmental cues protect plants from growing too early, but to understand how climate change will alter the timing and magnitude of plant growth, experiments need to independently manipulate temperature and snowmelt. Here, we demonstrate that altered seasonality through experimental warming and earlier snowmelt led to earlier plant growth, but the aboveground production response varied among plant functional groups. Earlier snowmelt without warming led to early leaf emergence, but often slowed the rate of leaf expansion and had limited effects on aboveground production. Experimental warming alone had small and inconsistent effects on aboveground phenology, while the effect of the combined treatment resembled that of early snowmelt alone. Experimental warming led to greater aboveground production among the graminoids, limited changes among deciduous shrubs and decreased production in one of the dominant evergreen shrubs. As a result, we predict that early onset of the growing season may favour early growing plant species, even those that do not shift the timing of leaf expansion. Published by Oxford University Press on behalf of the Annals of Botany Company.

  3. Earlier Age at Menopause, Work and Tobacco Smoke Exposure

    PubMed Central

    Fleming, Lora E; Levis, Silvina; LeBlanc, William G; Dietz, Noella A; Arheart, Kristopher L; Wilkinson, James D; Clark, John; Serdar, Berrin; Davila, Evelyn P; Lee, David J

    2009-01-01

    Objective Earlier age at menopause onset has been associated with increased all cause, cardiovascular, and cancer mortality risks. Risk of earlier age at menopause associated with primary and secondary tobacco smoke exposure was assessed. Design Cross-sectional study using a nationally representative sample of US women. Methods 7596 women participants (representing an estimated 79 million US women) from the National Health and Nutrition Examination Survey III were asked: time since last menstrual period, occupation, and tobacco use (including home and workplace secondhand smoke (SHS) exposure). Blood cotinine and follicle-stimulating hormone (FSH) levels were assessed. Logistic regressions for the odds of earlier age at menopause, stratified on race/ethnicity in women 25-50 years and adjusted for survey design, were controlled for age, BMI, education, tobacco smoke exposure, and occupation. Results Among 5029 US women ≥ 25 years with complete data, earlier age at menopause was found among all smokers, and among service and manufacturing industry sector workers. Among women age 25-50 years, there was an increased risk of earlier age at menopause with both primary smoking and with SHS exposure, particularly among Black women. Conclusions Primary tobacco use and SHS exposure were associated with an increased odds of earlier age at menopause in a representative sample of US women. Earlier age at menopause was found for some women worker groups with greater potential occupational SHS exposure. Thus, control of SHS exposures in the workplace may decrease the risk of mortality and morbidity associated with earlier age at menopause in US women workers. PMID:18626414

  4. Tidal Wave II Revisited: A Review of Earlier Enrollment Projections for California Higher Education.

    ERIC Educational Resources Information Center

    Hayward, Gerald C.; Breneman, David W.; Estrada, Leobardo F.

    This report examined enrollment projections for higher education institutions in California in relation to earlier projections conducted in the mid-1990s that forecasted steep declines in enrollment. It notes that California's remarkable economic recovery over the last several years has allowed it to fund higher education enrollment growth at a…

  5. Organized screening detects breast cancer at earlier stage regardless of molecular phenotype.

    PubMed

    Holloway, Claire M B; Jiang, Li; Whitehead, Marlo; Racz, Jennifer M; Groome, Patti A

    2018-06-16

    Mortality reduction attributable to organized breast screening is modest. Screening may be less effective at detecting more aggressive cancers at an earlier stage. This study was conducted to determine the relative efficacy of screening mammography to detect cancers at an earlier stage by molecular phenotype. We identified 2882 women with primary invasive breast cancer diagnosed between January 1, 2008 and December 31, 2012 and who had a mammogram through the Ontario Breast Screening Program in the 28 months before diagnosis. Five tumor phenotypes were defined by expression of estrogen (ER) and progesterone (PR) receptors and HER2/neu oncogene. We conducted univariable and multivariable analyses to describe the predictors of detection as an interval cancer. Additional analyses identified predictors of detection at stages II, III, or IV compared with stage I, by phenotype. Analyses were adjusted for the effects of age, grade, and breast density. ER negative and HER2 positive tumors were over-represented among interval cancers, and triple negative cancers were more likely than ER +/HER2 - cancers to be detected as interval cancers OR 2.5 (95% CI 2.0-3.2, p < 0.0001). Method of detection (interval vs. screen) and molecular phenotype were independently associated with stage at diagnosis (p < 0.0001), but there was no interaction between method of detection and phenotype (p = 0.44). In a screened population, triple negative and HER2 + breast cancers are diagnosed at a higher stage but this appears to be due to higher growth rates of these tumors rather than a relative inability of screening to detect them.

  6. Does Speech Emerge from Earlier Appearing Oral Motor Behaviors?.

    ERIC Educational Resources Information Center

    Moore, Christopher A.; Ruark, Jacki L.

    1996-01-01

    This study of the oral motor behaviors of seven toddlers (age 15 months) may be interpreted to indicate that: (1) mandibular coordination follows a developmental continuum from earlier emerging behaviors, such as chewing and sucking, through babbling, to speech, or (2) unique task demands give rise to distinct mandibular coordinative constraints…

  7. Scientific Knowledge Suppresses but Does Not Supplant Earlier Intuitions

    ERIC Educational Resources Information Center

    Shtulman, Andrew; Valcarcel, Joshua

    2012-01-01

    When students learn scientific theories that conflict with their earlier, naive theories, what happens to the earlier theories? Are they overwritten or merely suppressed? We investigated this question by devising and implementing a novel speeded-reasoning task. Adults with many years of science education verified two types of statements as quickly…

  8. Earlier predictors of eating disorder symptoms in 9-year-old children. A longitudinal study.

    PubMed

    Parkinson, Kathryn N; Drewett, Robert F; Le Couteur, Ann S; Adamson, Ashley J

    2012-08-01

    The aim of the study was to examine predictors of eating disorder symptoms in a population based sample at the earliest age at which they can be measured using the Children's Eating Attitudes Test. Data were collected from the longitudinal Gateshead Millennium Study cohort; 609 children participated in the 7 year data sweep (and their mothers and teachers), and 589 children participated in the 9 year data sweep. Eating disorder symptoms at 9 years were higher in boys, and in children from more deprived families. Higher eating disorder symptoms were associated with more body dissatisfaction at 9 years. Higher symptoms were predicted by higher levels of dietary restraint and of emotional symptoms, but not greater body dissatisfaction, 2 years earlier. The study showed that some correlates of high eating disorder symptoms found in adolescents and adults are also found in children, before the rise in diagnosable eating disorders over the pubertal period. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Toward Explaining Earlier Retirement after 1970.

    ERIC Educational Resources Information Center

    Ippolito, Richard A.

    1990-01-01

    Rule changes in the social security system and pension plans suggest that labor force participation rates for men aged 55 to 64 fell by 20 percent from 1970 through 1986 because of the increase in social security benefits and a change in private pension rules encouraging earlier retirement. (Author/JOW)

  10. A molecular dynamics study of liquid layering and thermal conductivity enhancement in nanoparticle suspensions

    NASA Astrophysics Data System (ADS)

    Paul, J.; Madhu, A. K.; Jayadeep, U. B.; Sobhan, C. B.; Peterson, G. P.

    2018-03-01

    Liquid layering is considered to be one of the factors contributing to the often anomalous enhancement in thermal conductivity of nanoparticle suspensions. The extent of this layering was found to be significant at lower particle sizes, as reported in an earlier work by the authors. In continuation to that work, an investigation was conducted to better understand the fundamental parameters impacting the reported anomalous enhancement in thermal conductivity of nanoparticle suspensions (nanofluids), utilizing equilibrium molecular dynamics simulations in a copper-argon system. Nanofluids containing nanoparticles of size less than 6 nm were investigated and studied analytically. The heat current auto-correlation function in the Green-Kubo formulation for thermal conductivity was decomposed into self-correlations and cross-correlations of different species and the kinetic, potential, collision and enthalpy terms of the dominant portion of the heat current vector. The presence of liquid layering around the nanoparticle was firmly established through simulations that show the dominant contribution of Ar-Ar self-correlation and the trend displayed by the kinetic-potential cross-correlation within the argon species.

  11. Very early predictors of conduct problems and crime: results from a national cohort study.

    PubMed

    Murray, Joseph; Irving, Barrie; Farrington, David P; Colman, Ian; Bloxsom, Claire A J

    2010-11-01

      Longitudinal research has produced a wealth of knowledge about individual, family, and social predictors of crime. However, nearly all studies have started after children are age 5, and little is known about earlier risk factors. The 1970 British Cohort Study is a prospective population survey of more than 16,000 children born in 1970. Pregnancy, birth, child, parent, and socioeconomic characteristics were measured from medical records, parent interviews, and child assessments at birth and age 5. Conduct problems were reported by parents at age 10, and criminal convictions were self-reported by study members at ages 30-34.   Early (up to age 5) psychosocial risk factors were strong predictors of conduct problems and criminal conviction. Among pregnancy and birth measures, only prenatal maternal smoking was strongly predictive. Risk factors were similar for girls and boys. Additive risk scores predicted antisocial behaviour quite strongly.   Risk factors from pregnancy to age 5 are quite strong predictors of conduct problems and crime. New risk assessment tools could be developed to identify young children at high risk for later antisocial behaviour. © 2010 The Authors. Journal of Child Psychology and Psychiatry © 2010 Association for Child and Adolescent Mental Health.

  12. Earlier adolescent substance use onset predicts stronger connectivity between reward and cognitive control brain networks.

    PubMed

    Weissman, David G; Schriber, Roberta A; Fassbender, Catherine; Atherton, Olivia; Krafft, Cynthia; Robins, Richard W; Hastings, Paul D; Guyer, Amanda E

    2015-12-01

    Early adolescent onset of substance use is a robust predictor of future substance use disorders. We examined the relation between age of substance use initiation and resting state functional connectivity (RSFC) of the core reward processing (nucleus accumbens; NAcc) to cognitive control (prefrontal cortex; PFC) brain networks. Adolescents in a longitudinal study of Mexican-origin youth reported their substance use annually from ages 10 to 16 years. At age 16, 69 adolescents participated in a resting state functional magnetic resonance imaging scan. Seed-based correlational analyses were conducted using regions of interest in bilateral NAcc. The earlier that adolescents initiated substance use, the stronger the connectivity between bilateral NAcc and right dorsolateral PFC, right dorsomedial PFC, right pre-supplementary motor area, right inferior parietal lobule, and left medial temporal gyrus. The regions that demonstrated significant positive linear relationships between the number of adolescent years using substances and connectivity with NAcc are nodes in the right frontoparietal network, which is central to cognitive control. The coupling of reward and cognitive control networks may be a mechanism through which earlier onset of substance use is related to brain function over time, a trajectory that may be implicated in subsequent substance use disorders. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Later endogenous circadian temperature nadir relative to an earlier wake time in older people

    NASA Technical Reports Server (NTRS)

    Duffy, J. F.; Dijk, D. J.; Klerman, E. B.; Czeisler, C. A.

    1998-01-01

    The contribution of the circadian timing system to the age-related advance of sleep-wake timing was investigated in two experiments. In a constant routine protocol, we found that the average wake time and endogenous circadian phase of 44 older subjects were earlier than that of 101 young men. However, the earlier circadian phase of the older subjects actually occurred later relative to their habitual wake time than it did in young men. These results indicate that an age-related advance of circadian phase cannot fully account for the high prevalence of early morning awakening in healthy older people. In a second study, 13 older subjects and 10 young men were scheduled to a 28-h day, such that they were scheduled to sleep at many circadian phases. Self-reported awakening from scheduled sleep episodes and cognitive throughput during the second half of the wake episode varied markedly as a function of circadian phase in both groups. The rising phase of both rhythms was advanced in the older subjects, suggesting an age-related change in the circadian regulation of sleep-wake propensity. We hypothesize that under entrained conditions, these age-related changes in the relationship between circadian phase and wake time are likely associated with self-selected light exposure at an earlier circadian phase. This earlier exposure to light could account for the earlier clock hour to which the endogenous circadian pacemaker is entrained in older people and thereby further increase their propensity to awaken at an even earlier time.

  14. Anisotropic thermal conductivity of thin polycrystalline oxide samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tiwari, A., E-mail: abhishektiwariiitr@gmail.com; Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, VIC 3800; Boussois, K.

    2013-11-15

    This paper reports about the development of a modified laser-flash technique and relation to measure the in-plane thermal diffusivity of thin polycrystalline oxide samples. Thermal conductivity is then calculated with the product of diffusivity, specific heat and density. Design and operating features for evaluating in-plane thermal conductivities are described. The technique is advantageous as thin samples are not glued together to measure in-plane thermal conductivities like earlier methods reported in literature. The approach was employed to study anisotropic thermal conductivity in alumina sheet, textured kaolin ceramics and montmorillonite. Since it is rare to find in-plane thermal conductivity values for suchmore » anisotropic thin samples in literature, this technique offers a useful variant to existing techniques.« less

  15. Research promises earlier warning for grapevine canker diseases

    USDA-ARS?s Scientific Manuscript database

    When it comes to detecting and treating vineyards for grapevine canker diseases (also called trunk diseases), like Botryosphaeria dieback (Bot canker), Esca, Eutypa dieback and Phomopsis dieback, the earlier the better, says plant pathologist Kendra Baumgartner, with the USDA’s Agricultural Research...

  16. Trend of earlier spring in central Europe continued

    NASA Astrophysics Data System (ADS)

    Ungersböck, Markus; Jurkovic, Anita; Koch, Elisabeth; Lipa, Wolfgang; Scheifinger, Helfried; Zach-Hermann, Susanne

    2013-04-01

    Modern phenology is the study of the timing of recurring biological events in the animal and plant world, the causes of their timing with regard to biotic and abiotic forces, and the interrelation among phases of the same or different species. The relationship between phenology and climate explains the importance of plant phenology for Climate Change studies. Plants require light, water, oxygen mineral nutrients and suitable temperature to grow. In temperate zones the seasonal life cycle of plants is primarily controlled by temperature and day length. Higher spring air temperatures are resulting in an earlier onset of the phenological spring in temperate and cool climate. On the other hand changes in phenology due to climate change do have impact on the climate system itself. Vegetation is a dynamic factor in the earth - climate system and has positive and negative feedback mechanisms to the biogeochemical and biogeophysical fluxes to the atmosphere Since the mid of the 1980s spring springs earlier in Europe and autumn is shifting back to the end of the year resulting in a longer vegetation period. The advancement of spring can be clearly attributed to temperature increase in the months prior to leaf unfolding and flowering, the timing of autumn is more complex and cannot easily be attributed to one or some few parameters. To demonstrate that the observed advancement of spring since the mid of 1980s is pro-longed in 2001 to 2010 and the delay of fall and the lengthening of the growing season is confirmed in the last decade we picked out several indicator plants from the PEP725 database www.pep725.eu. The PEP725 database collects data from different European network operators and thus offers a unique compilation of phenological observations; the database is regularly updated. The data follow the same classification scheme, the so called BBCH coding system so they can be compared. Lilac Syringa vulgaris, birch Betula pendula, beech Fagus and horse chestnut Aesculus

  17. An earlier de motu cordis.

    PubMed Central

    Daly, Walter J.

    2004-01-01

    Thirteenth century medical science, like medieval scholarship in general, was directed at reconciliation of Greek philosophy/science with prevailing medieval theology and philosophy. Peter of Spain [later Pope John XXI] was the leading medical scholar of his time. Peter wrote a long book on the soul. Imbedded in it was a chapter on the motion of the heart. Peter's De Motu was based on his own medical experience and Galen's De Usu Partium and De Usu Respirationis and De Usu Pulsuum. This earlier De Motu defines a point on the continuum of intellectual development leading to us and into the future. Thirteenth century scholarship relied on past authority to a degree that continues to puzzle and beg explanation. Images Fig. 1 PMID:17060956

  18. Earlier anal sexarche and co-occurring sexual risk are associated with current HIV-related risk behaviors among an online sample of men who have sex with men in Asia

    PubMed Central

    Cheung, Doug H.; Suharlim, Christian; Guadamuz, Thomas E.; Lim, Sin How; Koe, Stuart; Wei, Chongyi

    2014-01-01

    Studies of heterosexual populations across the globe and men who have sex with men (MSM) in a few developed countries showed that earlier sexual debut (sexarche) was associated with higher levels of co-occurring and subsequent HIV risk behaviors. We examined the relationships between earlier anal sexarche, unprotected earlier anal sexarche and current HIV risks among MSM from Asia. A cross-sectional online survey was conducted among MSM (N = 10,826) in Asia in 2010. Bivariate and multivariable logistic regressions were used to identify co-occurring (i.e., sexual experiences during sexarche) and current HIV-related risk factors (i.e., past six months) associated with earlier anal sexarche (before the age of 18) and unprotected earlier anal sexarche, respectively. Earlier anal sexarche was significantly associated with lack of condom use, being anal receptive or both receptive and insertive, and having a partner who were older during sexarche. It was also associated with current HIV-related risk behaviors including having multiple male sexual partners, having been paid for sex, and increased frequencies of recreational drug use. Unprotected earlier anal sexarche was significantly associated with inconsistent condom use in the past the six months. Improved and culturally sensitive sex education at schools should be included in national and regional HIV/AIDS prevention programming and policies in Asia. Such sex education programs should incorporate curriculum that address sexuality, sexual orientation, and sexual behaviors beyond those related to reproductive health. PMID:24920344

  19. Earlier anal sexarche and co-occurring sexual risk are associated with current HIV-related risk behaviors among an online sample of men who have sex with men in Asia.

    PubMed

    Cheung, Doug H; Suharlim, Christian; Guadamuz, Thomas E; Lim, Sin How; Koe, Stuart; Wei, Chongyi

    2014-12-01

    Studies of heterosexual populations across the globe and men who have sex with men (MSM) in a few developed countries showed that earlier sexual debut (sexarche) was associated with higher levels of co-occurring and subsequent HIV risk behaviors. We examined the relationships between earlier anal sexarche, unprotected earlier anal sexarche and current HIV risks among MSM from Asia. A cross-sectional online survey was conducted among MSM (N = 10,826) in Asia in 2010. Bivariate and multivariable logistic regressions were used to identify co-occurring (i.e., sexual experiences during sexarche) and current HIV-related risk factors (i.e., past 6 months) associated with earlier anal sexarche (before the age of 18) and unprotected earlier anal sexarche, respectively. Earlier anal sexarche was significantly associated with lack of condom use, being anal receptive or both receptive and insertive, and having a partner who were older during sexarche. It was also associated with current HIV-related risk behaviors including having multiple male sexual partners, having been paid for sex, and increased frequencies of recreational drug use. Unprotected earlier anal sexarche was significantly associated with inconsistent condom use in the past the 6 months. Improved and culturally sensitive sex education at schools should be included in national and regional HIV/AIDS prevention programming and policies in Asia. Such sex education programs should incorporate curriculum that address sexuality, sexual orientation, and sexual behaviors beyond those related to reproductive health.

  20. Cardiac Complications, Earlier Treatment, and Initial Disease Severity in Kawasaki Disease.

    PubMed

    Abrams, Joseph Y; Belay, Ermias D; Uehara, Ritei; Maddox, Ryan A; Schonberger, Lawrence B; Nakamura, Yosikazu

    2017-09-01

    To assess if observed higher observed risks of cardiac complications for patients with Kawasaki disease (KD) treated earlier may reflect bias due to confounding from initial disease severity, as opposed to any negative effect of earlier treatment. We used data from Japanese nationwide KD surveys from 1997 to 2004. Receipt of additional intravenous immunoglobulin (IVIG) (data available all years) or any additional treatment (available for 2003-2004) were assessed as proxies for initial disease severity. We determined associations between earlier or later IVIG treatment (defined as receipt of IVIG on days 1-4 vs days 5-10 of illness) and cardiac complications by stratifying by receipt of additional treatment or by using logistic modeling to control for the effect of receiving additional treatment. A total of 48 310 patients with KD were included in the analysis. In unadjusted analysis, earlier IVIG treatment was associated with a higher risk for 4 categories of cardiac complications, including all major cardiac complications (risk ratio, 1.10; 95% CI, 1.06-1.15). Stratifying by receipt of additional treatment removed this association, and earlier IVIG treatment became protective against all major cardiac complications when controlling for any additional treatment in logistic regressions (OR, 0.90; 95% CI, 0.80-1.00). Observed higher risks of cardiac complications among patients with KD receiving IVIG treatment on days 1-4 of the illness are most likely due to underlying higher initial disease severity, and patients with KD should continue to be treated with IVIG as early as possible. Published by Elsevier Inc.

  1. Travelling for earlier surgical treatment: the patient's view.

    PubMed Central

    Stewart, M; Donaldson, L J

    1991-01-01

    As part of the northern region's programme within the national waiting list initiative, schemes have been funded to test the feasibility and acceptability of offering patients the opportunity to travel further afield in order to receive earlier treatment. A total of 484 patients experiencing a long wait for routine surgical operations in the northern region were offered the opportunity to receive earlier treatment outside their local health district; 74% of the patients accepted the offer. The initiative was well received by the participating patients and the majority stated that if the need arose on a future occasion they would prefer to travel for treatment rather than have to wait for lengthy periods for treatment at their local hospital. These findings, interpreted in the light of the National Health Service reforms introduced in April 1991, suggest that for some types of care, patients would welcome greater flexibility in the placing of contracts, not merely reinforcement of historical patterns of referral. PMID:1823553

  2. Insight Into Illness and Cognition in Schizophrenia in Earlier and Later Life.

    PubMed

    Gerretsen, Philip; Voineskos, Aristotle N; Graff-Guerrero, Ariel; Menon, Mahesh; Pollock, Bruce G; Mamo, David C; Mulsant, Benoit H; Rajji, Tarek K

    2017-04-01

    Impaired insight into illness in schizophrenia is associated with illness severity and deficits in premorbid intellectual function, executive function, and memory. A previous study of patients aged 60 years and older found that illness severity and premorbid intellectual function accounted for variance in insight impairment. As such, we aimed to test whether similar relationships would be observed in earlier life. A retrospective analysis was performed on 1 large sample of participants (n = 171) with a DSM-IV-TR diagnosis of schizophrenia aged 19 to 79 years acquired from 2 studies: (1) a psychosocial intervention trial for older persons with schizophrenia (June 2008 to May 2014) and (2) a diffusion tensor imaging and genetics study of psychosis across the life span (February 2007 to December 2013). We assessed insight into illness using the Positive and Negative Syndrome Scale (PANSS) item G12 and explored its relationship to illness severity (PANSS total modified), premorbid intellectual function (Wechsler Test of Adult Reading [WTAR]), and cognition. Insight impairment was more severe in later life (≥ 60 years) than in earlier years (t = -3.75, P < .001). Across the whole sample, the variance of impaired insight was explained by PANSS total modified (Exp[B] = 1.070, P < .001) and WTAR scores (Exp[B] = 0.970, P = .028). Although age and cognition were correlated with impaired insight, they did not independently contribute to its variance. However, the relationships between impaired insight and illness severity and between impaired insight and cognition, particularly working memory, were stronger in later life than in earlier life. These results suggest an opportunity for intervention may exist with cognitive-enhancing neurostimulation or medications to improve insight into illness in schizophrenia across the life span. Original study registered on ClinicalTrials.gov (identifier: NCT00832845). © Copyright 2017 Physicians Postgraduate Press, Inc.

  3. Compulsive Buying: Earlier Illicit Drug Use, Impulse Buying, Depression, and Adult ADHD Symptoms

    PubMed Central

    Brook, Judith S.; Zhang, Chenshu; Brook, David W.; Leukefeld, Carl G.

    2015-01-01

    This longitudinal study examined the association between psychosocial antecedents, including illicit drug use, and adult compulsive buying (CB) across a 29-year time period from mean age 14 to mean age 43. Participants originally came from a community-based random sample of residents in two upstate New York counties. Multivariate linear regression analysis was used to study the relationship between the participant’s earlier psychosocial antecedents and adult CB in the fifth decade of life. The results of the multivariate linear regression analyses showed that gender (female), earlier adult impulse buying (IB), depressive mood, illicit drug use, and concurrent ADHD symptoms were all significantly associated with adult CB at mean age 43. It is important that clinicians treating CB in adults should consider the role of drug use, symptoms of ADHD, IB, depression, and family factors in CB. PMID:26165963

  4. Prescription stimulant use is associated with earlier onset of psychosis.

    PubMed

    Moran, Lauren V; Masters, Grace A; Pingali, Samira; Cohen, Bruce M; Liebson, Elizabeth; Rajarethinam, R P; Ongur, Dost

    2015-12-01

    A childhood history of attention deficit hyperactivity disorder (ADHD) is common in psychotic disorders, yet prescription stimulants may interact adversely with the physiology of these disorders. Specifically, exposure to stimulants leads to long-term increases in dopamine release. We therefore hypothesized that individuals with psychotic disorders previously exposed to prescription stimulants will have an earlier onset of psychosis. Age of onset of psychosis (AOP) was compared in individuals with and without prior exposure to prescription stimulants while controlling for potential confounding factors. In a sample of 205 patients recruited from an inpatient psychiatric unit, 40% (n = 82) reported use of stimulants prior to the onset of psychosis. Most participants were prescribed stimulants during childhood or adolescence for a diagnosis of ADHD. AOP was significantly earlier in those exposed to stimulants (20.5 vs. 24.6 years stimulants vs. no stimulants, p < 0.001). After controlling for gender, IQ, educational attainment, lifetime history of a cannabis use disorder or other drugs of abuse, and family history of a first-degree relative with psychosis, the association between stimulant exposure and earlier AOP remained significant. There was a significant gender × stimulant interaction with a greater reduction in AOP for females, whereas the smaller effect of stimulant use on AOP in males did not reach statistical significance. In conclusion, individuals with psychotic disorders exposed to prescription stimulants had an earlier onset of psychosis, and this relationship did not appear to be mediated by IQ or cannabis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Compulsive buying: Earlier illicit drug use, impulse buying, depression, and adult ADHD symptoms.

    PubMed

    Brook, Judith S; Zhang, Chenshu; Brook, David W; Leukefeld, Carl G

    2015-08-30

    This longitudinal study examined the association between psychosocial antecedents, including illicit drug use, and adult compulsive buying (CB) across a 29-year time period from mean age 14 to mean age 43. Participants originally came from a community-based random sample of residents in two upstate New York counties. Multivariate linear regression analysis was used to study the relationship between the participant's earlier psychosocial antecedents and adult CB in the fifth decade of life. The results of the multivariate linear regression analyses showed that gender (female), earlier adult impulse buying (IB), depressive mood, illicit drug use, and concurrent ADHD symptoms were all significantly associated with adult CB at mean age 43. It is important that clinicians treating CB in adults should consider the role of drug use, symptoms of ADHD, IB, depression, and family factors in CB. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. An earlier age of breast cancer diagnosis related to more frequent use of antiperspirants/deodorants and underarm shaving.

    PubMed

    McGrath, K G

    2003-12-01

    Breast cancer incidence suggests a lifestyle cause. A lifestyle factor used near the breast is the application of antiperspirants/deodorants accompanied by axillary shaving. A previous study did not support a link with breast cancer. If these habits have a role in breast cancer development, women using antiperspirants/deodorants and shaving their underarms frequently would be expected to have an earlier age of diagnosis than those doing so less often. An earlier age of diagnosis would also be expected in those starting to use deodorants and shaving at an earlier age. This is the first study to investigate the intensity of underarm exposure in a cohort of breast cancer survivors. Four hundred and thirty-seven females diagnosed with breast cancer were surveyed. Once grouped by their frequency of underarm hygiene habits, the mean age of diagnosis was the primary end point. Secondary end points included the overall frequency of these habits, and potential usage group confounding variables were evaluated. All statistical tests were two-sided. Frequency and earlier onset of antiperspirant/deodorant usage with underarm shaving were associated with an earlier age of breast cancer diagnosis. Combined habits are likely for this earlier age of diagnosis. In conclusion, underarm shaving with antiperspirant/deodorant use may play a role in breast cancer. It is not clear which of these components are involved. Reviewed literature insinuates absorption of aluminium salts facilitated by dermal barrier disruption. Case-controlled investigations are needed before alternative underarm hygiene habits are suggested.

  7. Epithelial conduction in hydromedusae.

    PubMed

    Mackie, G O; Passano, L M

    1968-10-01

    Sarsia, Euphysa, and other hydromedusae have been studied by electrophysiological techniques and are found to have nonnervous conducting epithelia resembling those described earlier for siphonophores. Simple, non-muscular epithelia fire singly or repetitively following brief electrical stimuli. The pulses recorded with suction electrodes are biphasic, initially positive, and show amplitudes of 0.75-2.0 mv, durations of 5-15 msec, and velocities of 15-35 cm/sec with short refractory periods. In the swimming muscle (myoepithelium) 2.0-4.0 mv composite events lasting 150-300 msec are associated with contraction waves. Propagation in nonnervous epithelia is typically all-or-none, nondecremental, and unpolarized. The subumbrellar endoderm lamella conducts independently of the adjacent ectoderm. The lower regions of the tentacles do not show propagated epithelial events. The spread of excitation in conducting epithelia and associated effector responses are described. Examples are given of interaction between events seemingly conducted in the nervous system and those in nonnervous epithelia. Either system may excite the other. Spontaneous activity, however, appears to originate in the nervous system. Conduction in nonnervous tissues is unaffected by excess Mg(++) in concentrations suppressing presumed nervous activity, although this may not be a wholly adequate criterion for distinguishing components of the two systems. Evidence from old work by Romanes is considered in the light of these findings and the general significance of epithelial conduction is discussed.

  8. Epithelial conduction in hydromedusae.

    PubMed

    Mackie, G O; Passano, L M

    1968-09-01

    Sarsia, Euphysa, and other hydromedusae have been studied by electrophysiological techniques and are found to have nonnervous conducting epithelia resembling those described earlier for siphonophores. Simple, nonmuscular epithelia fire singly or repetitively following brief electrical stimuli. The pulses recorded with suction electrodes are biphasic, initially positive, and show amplitudes of 0.75-2.0 mv, durations of 5-15 msec, and velocities of 15-35 cm/sec with short refractory periods. In the swimming muscle (myoepithelium) 2.0-4.0 mv composite events lasting 150-300 msec are associated with contraction waves. Propagation in nonnervous epithelia is typically all-or-none, nondecremental, and unpolarized. The subumbrellar endoderm lamella conducts independently of the adjacent ectoderm. The lower regions of the tentacles do not show propagated epithelial events. The spread of excitation in conducting epithelia and associated effector responses are described. Examples are given of interaction between events seemingly conducted in the nervous system and those in nonnervous epithelia. Either system may excite the other. Spontaneous activity, however, appears to originate in the nervous system. Conduction in nonnervous tissues is unaffected by excess Mg(++) in concentrations suppressing presumed nervous activity, although this may not be a wholly adequate criterion for distinguishing components of the two systems. Evidence from old work by Romanes is considered in the light of these findings and the general significance of epithelial conduction is discussed.

  9. Biological consequences of earlier snowmelt from desert dust deposition in alpine landscapes.

    PubMed

    Steltzer, Heidi; Landry, Chris; Painter, Thomas H; Anderson, Justin; Ayres, Edward

    2009-07-14

    Dust deposition to mountain snow cover, which has increased since the late 19(th) century, accelerates the rate of snowmelt by increasing the solar radiation absorbed by the snowpack. Snowmelt occurs earlier, but is decoupled from seasonal warming. Climate warming advances the timing of snowmelt and early season phenological events (e.g., the onset of greening and flowering); however, earlier snowmelt without warmer temperatures may have a different effect on phenology. Here, we report the results of a set of snowmelt manipulations in which radiation-absorbing fabric and the addition and removal of dust from the surface of the snowpack advanced or delayed snowmelt in the alpine tundra. These changes in the timing of snowmelt were superimposed on a system where the timing of snowmelt varies with topography and has been affected by increased dust loading. At the community level, phenology exhibited a threshold response to the timing of snowmelt. Greening and flowering were delayed before seasonal warming, after which there was a linear relationship between the date of snowmelt and the timing of phenological events. Consequently, the effects of earlier snowmelt on phenology differed in relation to topography, which resulted in increasing synchronicity in phenology across the alpine landscape with increasingly earlier snowmelt. The consequences of earlier snowmelt from increased dust deposition differ from climate warming and include delayed phenology, leading to synchronized growth and flowering across the landscape and the opportunity for altered species interactions, landscape-scale gene flow via pollination, and nutrient cycling.

  10. Missed opportunities for earlier diagnosis of HIV in patients who presented with advanced HIV disease: a retrospective cohort study

    PubMed Central

    Levy, Itzchak; Maor, Yasmin; Mahroum, Naim; Olmer, Liraz; Wieder, Anat; Litchevski, Vladislav; Mor, Orna; Rahav, Galia

    2016-01-01

    Objective To quantify and characterise missed opportunities for earlier HIV diagnosis in patients diagnosed with advanced HIV. Design A retrospective observational cohort study. Setting A central tertiary medical centre in Israel. Measures The proportion of patients with advanced HIV, the proportion of missed opportunities to diagnose them earlier, and the rate of clinical indicator diseases (CIDs) in those patients. Results Between 2010 and 2015, 356 patients were diagnosed with HIV, 118 (33.4%) were diagnosed late, 57 (16%) with advanced HIV disease. Old age (OR=1.45 (95% CI 1.16 to 1.74)) and being heterosexual (OR=2.65 (95% CI 1.21 to 5.78)) were significant risk factors for being diagnosed late. All patients with advanced disease had at least one CID that did not lead to an HIV test in the 5 years prior to AIDS diagnosis. The median time between CID and AIDS diagnosis was 24 months (IQR 10–30). 60% of CIDs were missed by a general practitioner and 40% by a specialist. Conclusions Missed opportunities to early diagnosis of HIV occur in primary and secondary care. Lack of national guidelines, lack of knowledge regarding CIDs and communication barriers with patients may contribute to a late diagnosis of HIV. PMID:28186940

  11. Earlier Mother's Age at Menarche Predicts Rapid Infancy Growth and Childhood Obesity

    PubMed Central

    Ong, Ken K; Northstone, Kate; Wells, Jonathan CK; Rubin, Carol; Ness, Andy R; Golding, Jean; Dunger, David B

    2007-01-01

    Background Early menarche tends to be preceded by rapid infancy weight gain and is associated with increased childhood and adult obesity risk. As age at menarche is a heritable trait, we hypothesised that age at menarche in the mother may in turn predict her children's early growth and obesity risk. Methods and Findings We tested associations between mother's age at menarche, mother's adult body size and obesity risk, and her children's growth and obesity risk in 6,009 children from the UK population-based Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort who had growth and fat mass at age 9 y measured by dual-energy X-ray absorptiometry. A subgroup of 914 children also had detailed infancy and childhood growth data. In the mothers, earlier menarche was associated with shorter adult height (by 0.64 cm/y), increased weight (0.92 kg/y), and body mass index (BMI, 0.51 kg/m2/y; all p < 0.001). In contrast, in her children, earlier mother's menarche predicted taller height at 9 y (by 0.41 cm/y) and greater weight (0.80 kg/y), BMI (0.29 kg/m2/y), and fat mass index (0.22 kg/m2/year; all p < 0.001). Children in the earliest mother's menarche quintile (≤11 y) were more obese than the oldest quintile (≥15 y) (OR, 2.15, 95% CI 1.46 to 3.17; p < 0.001, adjusted for mother's education and BMI). In the subgroup, children in the earliest quintile showed faster gains in weight (p < 0.001) and height (p < 0.001) only from birth to 2 y, but not from 2 to 9 y (p = 0.3–0.8). Conclusions Earlier age at menarche may be a transgenerational marker of a faster growth tempo, characterised by rapid weight gain and growth, particularly during infancy, and leading to taller childhood stature, but likely earlier maturation and therefore shorter adult stature. This growth pattern confers increased childhood and adult obesity risks. PMID:17455989

  12. Epithelial Conduction in Hydromedusae

    PubMed Central

    Mackie, G. O.; Passano, L. M.

    1968-01-01

    Sarsia, Euphysa, and other hydromedusae have been studied by electrophysiological techniques and are found to have nonnervous conducting epithelia resembling those described earlier for siphonophores. Simple, nonmuscular epithelia fire singly or repetitively following brief electrical stimuli. The pulses recorded with suction electrodes are biphasic, initially positive, and show amplitudes of 0.75–2.0 mv, durations of 5–15 msec, and velocities of 15–35 cm/sec with short refractory periods. In the swimming muscle (myoepithelium) 2.0–4.0 mv composite events lasting 150–300 msec are associated with contraction waves. Propagation in nonnervous epithelia is typically all-or-none, nondecremental, and unpolarized. The subumbrellar endoderm lamella conducts independently of the adjacent ectoderm. The lower regions of the tentacles do not show propagated epithelial events. The spread of excitation in conducting epithelia and associated effector responses are described. Examples are given of interaction between events seemingly conducted in the nervous system and those in nonnervous epithelia. Either system may excite the other. Spontaneous activity, however, appears to originate in the nervous system. Conduction in nonnervous tissues is unaffected by excess Mg++ in concentrations suppressing presumed nervous activity, although this may not be a wholly adequate criterion for distinguishing components of the two systems. Evidence from old work by Romanes is considered in the light of these findings and the general significance of epithelial conduction is discussed. PMID:19873635

  13. Epithelial Conduction in Hydromedusae

    PubMed Central

    Mackie, G. O.; Passano, L. M.

    1968-01-01

    Sarsia, Euphysa, and other hydromedusae have been studied by electrophysiological techniques and are found to have nonnervous conducting epithelia resembling those described earlier for siphonophores. Simple, non-muscular epithelia fire singly or repetitively following brief electrical stimuli. The pulses recorded with suction electrodes are biphasic, initially positive, and show amplitudes of 0.75–2.0 mv, durations of 5–15 msec, and velocities of 15–35 cm/sec with short refractory periods. In the swimming muscle (myoepithelium) 2.0–4.0 mv composite events lasting 150–300 msec are associated with contraction waves. Propagation in nonnervous epithelia is typically all-or-none, nondecremental, and unpolarized. The subumbrellar endoderm lamella conducts independently of the adjacent ectoderm. The lower regions of the tentacles do not show propagated epithelial events. The spread of excitation in conducting epithelia and associated effector responses are described. Examples are given of interaction between events seemingly conducted in the nervous system and those in nonnervous epithelia. Either system may excite the other. Spontaneous activity, however, appears to originate in the nervous system. Conduction in nonnervous tissues is unaffected by excess Mg++ in concentrations suppressing presumed nervous activity, although this may not be a wholly adequate criterion for distinguishing components of the two systems. Evidence from old work by Romanes is considered in the light of these findings and the general significance of epithelial conduction is discussed. PMID:4386662

  14. Traumatic Brain Injury History is Associated with Earlier Age of Onset of Alzheimer Disease

    PubMed Central

    LoBue, Christian; Wadsworth, Hannah; Wilmoth, Kristin; Clem, Matthew; Hart, John; Womack, Kyle B.; Didehbani, Nyaz; Lacritz, Laura H.; Rossetti, Heidi C.; Cullum, C. Munro

    2016-01-01

    Objective This study examined whether a history of traumatic brain injury (TBI) is associated with earlier onset of Alzheimer disease (AD), independent of apolipoprotein ε4 status (Apoe4) and gender. Method Participants with a clinical diagnosis of AD (n=7625) were obtained from the National Alzheimer’s Coordinating Center Uniform Data Set, and categorized based on self-reported lifetime TBI with loss of consciousness (LOC) (TBI+ vs TBI-) and presence of Apoe4. ANCOVAs, controlling for gender, race, and education were used to examine the association between history of TBI, presence of Apoe4, and an interaction of both risk factors on estimated age of AD onset. Results Estimated AD onset differed by TBI history and Apoe4 independently (p’s <.001). The TBI+ group had a mean age of onset 2.5 years earlier than the TBI- group. Likewise, Apoe4 carriers had a mean age of onset 2.3 years earlier than non-carriers. While the interaction was non-significant (p = .34), participants having both a history of TBI and Apoe4 had the earliest mean age of onset compared to those with a TBI history or Apoe4 alone (MDifference = 2.8 & 2.7 years, respectively). These results remained unchanged when stratified by gender. Conclusions History of self-reported TBI can be associated with an earlier onset of AD-related cognitive decline, regardless of Apoe4 status and gender. TBI may be related to an underlying neurodegenerative process in AD, but the implications of age at time of injury, severity, and repetitive injuries remain unclear. PMID:27855547

  15. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The potential...

  16. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The potential...

  17. Study of hopping type conduction from AC conductivity in multiferroic composite

    NASA Astrophysics Data System (ADS)

    Pandey, Rabichandra; Guha, Shampa; Pradhan, Lagen Kumar; Kumar, Sunil; Supriya, Sweety; Kar, Manoranjan

    2018-05-01

    0.5BiFe0.80Ti0.20O3-0.5Co0.5Ni0.5Fe2O4(BFTO-CNFO) multiferroic composite was prepared by planetary ball mill method. X-ray diffraction analysis confirms the formation of the compound with the simultaneous presence of spinel Co0.5Ni0.5Fe2O4 (CNFO) and perovskite BiFe0.80Ti0.20O3 (BFTO) phase. Temperature dependent dielectric permittivity and loss tangent were studied with a frequency range of 100Hz to 1MHz. AC conductivity study was performed to analyze the electrical conduction behaviour in the composite. Johnscher's power law was employed to the AC conductivity data to understand the hopping of localized charge carrier in the compound. The binding energy, minimum hopping distance and density of states of the charge carriers in the composite were evaluated from the AC conductivity data. Minimum hopping distance is found to be in order of Angstrom (Å).

  18. Reading-Related Skills in Earlier- and Later-Schooled Children

    ERIC Educational Resources Information Center

    Cunningham, Anna J.; Carroll, Julia M.

    2011-01-01

    We investigate the effects of age-related factors and formal instruction on the development of reading-related skills in children aged 4 and 7 years. Age effects were determined by comparing two groups of children at the onset of formal schooling; one aged 7 (later-schooled) and one aged 4 (earlier-schooled). Schooling effects were measured by…

  19. Perceptual sensitivity to spectral properties of earlier sounds during speech categorization.

    PubMed

    Stilp, Christian E; Assgari, Ashley A

    2018-02-28

    Speech perception is heavily influenced by surrounding sounds. When spectral properties differ between earlier (context) and later (target) sounds, this can produce spectral contrast effects (SCEs) that bias perception of later sounds. For example, when context sounds have more energy in low-F 1 frequency regions, listeners report more high-F 1 responses to a target vowel, and vice versa. SCEs have been reported using various approaches for a wide range of stimuli, but most often, large spectral peaks were added to the context to bias speech categorization. This obscures the lower limit of perceptual sensitivity to spectral properties of earlier sounds, i.e., when SCEs begin to bias speech categorization. Listeners categorized vowels (/ɪ/-/ɛ/, Experiment 1) or consonants (/d/-/g/, Experiment 2) following a context sentence with little spectral amplification (+1 to +4 dB) in frequency regions known to produce SCEs. In both experiments, +3 and +4 dB amplification in key frequency regions of the context produced SCEs, but lesser amplification was insufficient to bias performance. This establishes a lower limit of perceptual sensitivity where spectral differences across sounds can bias subsequent speech categorization. These results are consistent with proposed adaptation-based mechanisms that potentially underlie SCEs in auditory perception. Recent sounds can change what speech sounds we hear later. This can occur when the average frequency composition of earlier sounds differs from that of later sounds, biasing how they are perceived. These "spectral contrast effects" are widely observed when sounds' frequency compositions differ substantially. We reveal the lower limit of these effects, as +3 dB amplification of key frequency regions in earlier sounds was enough to bias categorization of the following vowel or consonant sound. Speech categorization being biased by very small spectral differences across sounds suggests that spectral contrast effects occur

  20. Smoking is associated with earlier time to revision of total knee arthroplasty.

    PubMed

    Lim, Chin Tat; Goodman, Stuart B; Huddleston, James I; Harris, Alex H S; Bhowmick, Subhrojyoti; Maloney, William J; Amanatullah, Derek F

    2017-10-01

    Smoking is associated with early postoperative complications, increased length of hospital stay, and an increased risk of revision after total knee arthroplasty (TKA). However, the effect of smoking on time to revision TKA is unknown. A total of 619 primary TKAs referred to an academic tertiary center for revision TKA were retrospectively stratified according to the patient smoking status. Smoking status was then analyzed for associations with time to revision TKA using a Chi square test. The association was also analyzed according to the indication for revision TKA. Smokers (37/41, 90%) have an increased risk of earlier revision for any reason compared to non-smokers (274/357, 77%, p=0.031). Smokers (37/41, 90%) have an increased risk of earlier revision for any reason compared to ex-smokers (168/221, 76%, p=0.028). Subgroup analysis did not reveal a difference in indication for revision TKA (p>0.05). Smokers are at increased risk of earlier revision TKA when compared to non-smokers and ex-smokers. The risk for ex-smokers was similar to that of non-smokers. Smoking appears to have an all-or-none effect on earlier revision TKA as patients who smoked more did not have higher risk of early revision TKA. These results highlight the need for clinicians to urge patients not to begin smoking and encourage smokers to quit smoking prior to primary TKA. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. The associations of earlier trauma exposures and history of mental disorders with PTSD after subsequent traumas

    PubMed Central

    Kessler, Ronald C.; Aguilar-Gaxiola, Sergio; Alonso, Jordi; Bromet, Evelyn J.; Gureje, Oye; Karam, Elie G.; Koenen, Karestan C.; Lee, Sing; Liu, Howard; Pennell, Beth-Ellen; Petukhova, Maria V.; Sampson, Nancy A.; Shahly, Victoria L.; Stein, Dan J.; Atwoli, Lukoye; Borges, Guilherme; Bunting, Brendan; de Girolamo, Giovanni; Gluzman, Semyon; Haro, Josep Maria; Hinkov, Hristo; Kawakami, Norito; Kovess-Masfety, Viviane; Navarro-Mateu, Fernando; Posada-Villa, Jose; Scott, Kate M.; Shalev, Arieh Y.; Have, Margreet ten; Torres, Yolanda; Viana, Maria Carmen; Zaslavsky, Alan M.

    2017-01-01

    Although earlier trauma exposure is known to predict post-traumatic stress disorder (PTSD) after subsequent traumas, it is unclear if this association is limited to cases where the earlier trauma led to PTSD. Resolution of this uncertainty has important implications for research on pre-trauma vulnerability to PTSD. We examined this issue in the WHO World Mental Health (WMH) Surveys with 34,676 respondents who reported lifetime trauma exposure. One lifetime trauma was selected randomly for each respondent. DSM-IV PTSD due to that trauma was assessed. We reported in a previous paper that four earlier traumas involving interpersonal violence significantly predicted PTSD after subsequent random traumas (OR=1.3–2.5). We also assessed 14 lifetime DSM-IV mood, anxiety, disruptive behavior, and substance disorders prior to random traumas. We show in the current report that only prior anxiety disorders significantly predicted PTSD in a multivariate model (OR=1.5–4.3) and that these disorders interacted significantly with three of the earlier traumas (witnessing atrocities, physical violence victimization, rape). History of witnessing atrocities significantly predicted PTSD after subsequent random traumas only among respondents with prior PTSD (OR=5.6). Histories of physical violence victimization (OR=1.5) and rape after age 17 (OR=17.6) significantly predicted only among respondents with no history of prior anxiety disorders. Although only preliminary due to reliance on retrospective reports, these results suggest that history of anxiety disorders and history of a limited number of earlier traumas might usefully be targeted in future prospective studies as distinct foci of research on individual differences in vulnerability to PTSD after subsequent traumas. PMID:28924183

  2. Floodplains within reservoirs promote earlier spawning of white crappies Pomoxis annularis

    USGS Publications Warehouse

    Miranda, Leandro E.; Dagel, Jonah D.; Kaczka, Levi J.; Mower, Ethan; Wigen, S. L.

    2015-01-01

    Reservoirs impounded over floodplain rivers are unique because they may include within their upper reaches extensive shallow water stored over preexistent floodplains. Because of their relatively flat topography and riverine origin, floodplains in the upper reaches of reservoirs provide broad expanses of vegetation within a narrow range of reservoir water levels. Elsewhere in the reservoir, topography creates a band of shallow water along the contour of the reservoir where vegetation often does not grow. Thus, as water levels rise, floodplains may be the first vegetated habitats inundated within the reservoir. We hypothesized that shallow water in reservoir floodplains would attract spawning white crappies Pomoxis annularis earlier than reservoir embayments. Crappie relative abundance over five years in floodplains and embayments of four reservoirs increased as spawning season approached, peaked, and decreased as fish exited shallow water. Relative abundance peaked earlier in floodplains than embayments, and the difference was magnified with higher water levels. Early access to suitable spawning habitat promotes earlier spawning and may increase population fitness. Recognition of the importance of reservoir floodplains, an understanding of how reservoir water levels can be managed to provide timely connectivity to floodplains, and conservation of reservoir floodplains may be focal points of environmental management in reservoirs.

  3. View northeast, wharf A, portion AA, details showing earlier piers ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View northeast, wharf A, portion AA, details showing earlier piers and braces sloping toward water, reused charred plates for existing decking - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  4. Variations in a university subject pool as a function of earlier or later participation and self-report: a replication and extension.

    PubMed

    Bernard, Larry C; Walsh, R Patricia

    2002-10-01

    The present study replicated and extended earlier research on temporal sampling effects in university subject pools. Data were obtained from 236 participants, 79 men and 157 women, in a university subject pool during a 15-wk. semester. Without knowing the purpose of the study, participants self-selected to participate earlier (Weeks 4 and 5; n = 105) or later (Weeks 14 and 15; n = 131). Three hypotheses were investigated: (1) that the personality patterns of earlier and later participants on the NEO Personality Inventory-Revised and the Personality Research Form differ significantly, with earlier participants scoring higher on the latter scales reflecting social responsibility and higher on former Conscientiousness and Neuroticism scales; (2) that there are similar significant differences between participants in the earlier and later groups compared to the male and female college normative samples for the two tests: and (3) that earlier participants will have higher actual Scholastic Assessment Test scores and Grade Point Averages. Also investigated was whether participants' foreknowledge that their actual Scholastic Assessment Test scores and Grade Point Averages would be obtained would affect their accuracy of self-report. In contrast to prior research, neither the first nor second hypothesis was supported by the current study; there do not appear to be consistent differences on personality variables. However, the third hypothesis was supported. Earlier participants had higher actual high school Grade Point Average, college Grade Point Average, and Scholastic Assessment Test Verbal scores. Foreknowledge that actual Scholastic Assessment Test scores and Grade Point Averages would be obtained did not affect the accuracy of self-report. In addition, later participants significantly over-reported their scores, and significantly more women than men and more first-year than senior-year subjects participated in the early group.

  5. Earlier Parental Set Bedtimes as a Protective Factor Against Depression and Suicidal Ideation

    PubMed Central

    Gangwisch, James E.; Babiss, Lindsay A.; Malaspina, Dolores; Turner, J. Blake; Zammit, Gary K.; Posner, Kelly

    2010-01-01

    Study Objectives: To examine the relationships between parental set bedtimes, sleep duration, and depression as a quasi-experiment to explore the potentially bidirectional relationship between short sleep duration and depression. Short sleep duration has been shown to precede depression, but this could be explained as a prodromal symptom of depression. Depression in an adolescent can affect his/her chosen bedtime, but it is less likely to affect a parent's chosen set bedtime which can establish a relatively stable upper limit that can directly affect sleep duration. Design: Multivariate cross-sectional analyses of the ADD Health using logistic regression. Setting: United States nationally representative, school-based, probability-based sample in 1994-96. Participants: Adolescents (n = 15,659) in grades 7 to 12. Measurements and Results: Adolescents with parental set bedtimes of midnight or later were 24% more likely to suffer from depression (OR = 1.24, 95% CI 1.04-1.49) and 20% more likely to have suicidal ideation (1.20, 1.01-1.41) than adolescents with parental set bedtimes of 10:00 PM or earlier, after controlling for covariates. Consistent with sleep duration and perception of getting enough sleep acting as mediators, the inclusion of these variables in the multivariate models appreciably attenuated the associations for depression (1.07, 0.88-1.30) and suicidal ideation (1.09, 0.92-1.29). Conclusions: The results from this study provide new evidence to strengthen the argument that short sleep duration could play a role in the etiology of depression. Earlier parental set bedtimes could therefore be protective against adolescent depression and suicidal ideation by lengthening sleep duration. Citation: Gangwisch JE; Babiss LA; Malaspina D; Turner JB; Zammit GK; Posner K. Earlier parental set bedtimes as a protective factor against depression and suicidal ideation. SLEEP 2010;33(1):97-106. PMID:20120626

  6. Retrospective study of reasons for improved survival in patients with breast cancer in east Anglia: earlier diagnosis or better treatment.

    PubMed Central

    Stockton, D.; Davies, T.; Day, N.; McCann, J.

    1997-01-01

    OBJECTIVES: To investigate the recent fall in mortality from breast cancer in England and Wales, and to determine the relative contributions of improvements in treatment and earlier detection of tumours. DESIGN: Retrospective study of all women with breast cancer registered by the East Anglian cancer registry and diagnosed between 1982 and 1989. SUBJECTS: 3965 patients diagnosed 1982-5 compared with 4665 patients diagnosed 1986-9, in three age groups 0-49, 50-64, > or = 65 years, with information on stage at diagnosis and survival. MAIN OUTCOME MEASURES: Three year relative survival rates by time period, age group, and stage; relative hazard ratios for each time period and age group derived from Cox's proportional hazards model, adjusted for single year of age and stage. RESULTS: Survival improved in the later time period, although there was little stage specific improvement. The proportion of early stage tumours increased especially in the 50-64 year age group, and adjustment for stage accounted for over half of the improvement in survival in women aged under 65 years. CONCLUSION: Over half of the drop in mortality in women aged under 65 years seems to be attributable to earlier detection of tumours, which has been observed since the mid-1980s. This could have resulted from an increase in breast awareness predating the start of the breast screening programme. PMID:9056796

  7. Health care strategies to promote earlier presentation of symptomatic breast cancer: perspectives of women and family physicians

    PubMed Central

    Heisey, R.; Clemons, M.; Granek, L.; Fergus, K.; Hum, S.; Lord, B.; McCready, D.R.; Fitzgerald, B.

    2011-01-01

    Background Many women with symptoms suggestive of a breast cancer diagnosis delay presentation to their family physician. Although factors associated with delay have been well described, there is a paucity of data on strategies to mitigate delay. Objectives We conducted a qualitative research project to examine factors related to delay and to identify health care system changes that might encourage earlier presentation. Methods Individual semi-structured interviews were conducted with women who sought care 12 weeks or more after self-detection of breast cancer symptoms and with family physicians whose practices included patients meeting that criterion. Results The women and physicians both suggested a need for clearer screening mammography guidelines for women 40–49 years of age and for better messaging concerning breast awareness. The use of additional hopeful testimonials from breast cancer survivors were suggested to help dispel the notion of cancer as a “death sentence.” Educational initiatives were proposed, aimed at both increasing awareness of “non-lump” breast cancer symptoms and advising women that a previous benign diagnosis does not ensure that future symptoms are not cancer. Women wanted empathic nonjudgmental access to care. Improved methods to track compliance with screening mammography and with periodic health exams and access to a rapid diagnostic process were suggested. Conclusions A list of “at-risk situations for delay” in diagnosis of breast cancer was developed for physicians to assist in identifying women who might delay. Health care system changes actionable both at the health policy level and in the family physician’s office were identified to encourage earlier presentation of women with symptomatic breast cancer. PMID:21980254

  8. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Conduct of a study. 792.130 Section... ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems...

  9. Female conduct disorder: health status in young adulthood.

    PubMed

    Pajer, Kathleen A; Kazmi, Alamdar; Gardner, William P; Wang, Yun

    2007-01-01

    One of the risk factors for poor adult health may be adolescent antisocial behavior, especially in girls. This study was conducted to determine if negative young adult health outcomes in girls who previously had adolescent antisocial behavior could be explained by demographic factors and pre-existing health problems. This 3-year longitudinal study recruited 93 girls, ages 15-17 years (52 with conduct disorder [CD]; 41 with no psychiatric illness [normal controls; NC]) from the community. Baseline interviews of girls and parents collected demographic, psychiatric, and medical history data. Three annual interviews collected data about medical problems, health care service utilization, and reproductive health. In addition, the final follow-up included a standardized self-report questionnaire about young adult health status. CD and NC groups did not differ in age, racial composition, social class, proportion of smokers, or drug and alcohol experimentation. They were qualitatively different in baseline medical histories. Controlling for age at follow-up and baseline medical problems, the CD group as young adults had worse overall health, more discomfort, higher rates of unhealthy habits, lower rates of healthy behaviors, and more pregnancies at earlier ages. There were no group differences in rates of disorders, injuries, or health care usage. Adolescent girls with CD as young adults have poorer overall health, more discomfort, more health risk behaviors, and earlier onset of adult reproductive behaviors, even when controlling for demographic factors and pre-existing health history. Clinical and research implications are discussed.

  10. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Conduct of a study. 792.130 Section 792... (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be...

  11. Earlier versus later continuous Kangaroo Mother Care (KMC) for stable low-birth-weight infants: a randomized controlled trial.

    PubMed

    Nagai, S; Andrianarimanana, D; Rabesandratana, N; Yonemoto, N; Nakayama, T; Mori, R

    2010-06-01

    The aim of this study was to examine the effectiveness of earlier continuous Kangaroo Mother Care (KMC) for relatively stable low-birth-weight (LBW) infants in a resource-limited country. A randomized controlled trial was performed in LBW infants at a referral hospital in Madagascar. Earlier continuous KMC (intervention) was begun as soon as possible, within 24 h postbirth, and later continuous KMC (control: conventional care) was begun after complete stabilization (generally after 24 h postbirth). Main outcome measure was mortality during the first 28 days postbirth. This trial was registered with ClinicalTrials.gov, NCT00531492. A total of 73 infants (intervention 37, control 36) were included. Earlier continuous KMC had higher but no statistically different mortality in the first 28 days postbirth (1 vs. 2; risk ratio, 1.95; 95% CIs, 0.18-20.53; p = 1.00). There were no differences in incidence of morbidities. Body weight loss from birth to 24 h postbirth was significantly less in earlier KMC infants compared with later KMC infants. (-34.81 g vs. -73.97 g; mean difference, 39.16 g; 95% CIs, 10.30-68.03; p = 0.01; adjusted p = 0.02). Adverse events and duration of hospitalization were not different between the two groups. Further evaluations of earlier continuous KMC including measurement of KMC dose, are needed in resource-limited countries.

  12. The associations of earlier trauma exposures and history of mental disorders with PTSD after subsequent traumas.

    PubMed

    Kessler, R C; Aguilar-Gaxiola, S; Alonso, J; Bromet, E J; Gureje, O; Karam, E G; Koenen, K C; Lee, S; Liu, H; Pennell, B-E; Petukhova, M V; Sampson, N A; Shahly, V; Stein, D J; Atwoli, L; Borges, G; Bunting, B; de Girolamo, G; Gluzman, S F; Haro, J M; Hinkov, H; Kawakami, N; Kovess-Masfety, V; Navarro-Mateu, F; Posada-Villa, J; Scott, K M; Shalev, A Y; Ten Have, M; Torres, Y; Viana, M C; Zaslavsky, A M

    2017-09-19

    Although earlier trauma exposure is known to predict posttraumatic stress disorder (PTSD) after subsequent traumas, it is unclear whether this association is limited to cases where the earlier trauma led to PTSD. Resolution of this uncertainty has important implications for research on pretrauma vulnerability to PTSD. We examined this issue in the World Health Organization (WHO) World Mental Health (WMH) Surveys with 34 676 respondents who reported lifetime trauma exposure. One lifetime trauma was selected randomly for each respondent. DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition) PTSD due to that trauma was assessed. We reported in a previous paper that four earlier traumas involving interpersonal violence significantly predicted PTSD after subsequent random traumas (odds ratio (OR)=1.3-2.5). We also assessed 14 lifetime DSM-IV mood, anxiety, disruptive behavior and substance disorders before random traumas. We show in the current report that only prior anxiety disorders significantly predicted PTSD in a multivariate model (OR=1.5-4.3) and that these disorders interacted significantly with three of the earlier traumas (witnessing atrocities, physical violence victimization and rape). History of witnessing atrocities significantly predicted PTSD after subsequent random traumas only among respondents with prior PTSD (OR=5.6). Histories of physical violence victimization (OR=1.5) and rape after age 17 years (OR=17.6) significantly predicted only among respondents with no history of prior anxiety disorders. Although only preliminary due to reliance on retrospective reports, these results suggest that history of anxiety disorders and history of a limited number of earlier traumas might usefully be targeted in future prospective studies as distinct foci of research on individual differences in vulnerability to PTSD after subsequent traumas.Molecular Psychiatry advance online publication, 19 September 2017; doi:10.1038/mp.2017.194.

  13. Lessons learnt from the first controlled human malaria infection study conducted in Nairobi, Kenya.

    PubMed

    Hodgson, Susanne H; Juma, Elizabeth; Salim, Amina; Magiri, Charles; Njenga, Daniel; Molyneux, Sassy; Njuguna, Patricia; Awuondo, Ken; Lowe, Brett; Billingsley, Peter F; Cole, Andrew O; Ogwang, Caroline; Osier, Faith; Chilengi, Roma; Hoffman, Stephen L; Draper, Simon J; Ogutu, Bernhards; Marsh, Kevin

    2015-04-28

    Controlled human malaria infection (CHMI) studies, in which healthy volunteers are infected with Plasmodium falciparum to assess the efficacy of novel malaria vaccines and drugs, have become a vital tool to accelerate vaccine and drug development. CHMI studies provide a cost-effective and expeditious way to circumvent the use of large-scale field efficacy studies to deselect intervention candidates. However, to date few modern CHMI studies have been performed in malaria-endemic countries. An open-label, randomized pilot CHMI study was conducted using aseptic, purified, cryopreserved, infectious P. falciparum sporozoites (SPZ) (Sanaria® PfSPZ Challenge) administered intramuscularly (IM) to healthy Kenyan adults (n = 28) with varying degrees of prior exposure to P. falciparum. The purpose of the study was to establish the PfSPZ Challenge CHMI model in a Kenyan setting with the aim of increasing the international capacity for efficacy testing of malaria vaccines and drugs, and allowing earlier assessment of efficacy in a population for which interventions are being developed. This was part of the EDCTP-funded capacity development of the CHMI platform in Africa. This paper discusses in detail lessons learnt from conducting the first CHMI study in Kenya. Issues pertinent to the African setting, including community sensitization, consent and recruitment are considered. Detailed reasoning regarding the study design (for example, dose and route of administration of PfSPZ Challenge, criteria for grouping volunteers according to prior exposure to malaria and duration of follow-up post CHMI) are given and changes other centres may want to consider for future studies are suggested. Performing CHMI studies in an African setting presents unique but surmountable challenges and offers great opportunity for acceleration of malaria vaccine and drug development. The reflections in this paper aim to aid other centres and partners intending to use the CHMI model in Africa.

  14. Earlier time to aerobic exercise is associated with faster recovery following acute sport concussion.

    PubMed

    Lawrence, David Wyndham; Richards, Doug; Comper, Paul; Hutchison, Michael G

    2018-01-01

    To determine whether earlier time to initiation of aerobic exercise following acute concussion is associated with time to full return to (1) sport and (2) school or work. A retrospective stratified propensity score survival analysis of acute (≤14 days) concussion was used to determine whether time (days) to initiation of aerobic exercise post-concussion was associated with, both, time (days) to full return to (1) sport and (2) school or work. A total of 253 acute concussions [median (IQR) age, 17.0 (15.0-20.0) years; 148 (58.5%) males] were included in this study. Multivariate Cox regression models identified that earlier time to aerobic exercise was associated with faster return to sport and school/work adjusting for other covariates, including quintile propensity strata. For each successive day in delay to initiation of aerobic exercise, individuals had a less favourable recovery trajectory. Initiating aerobic exercise at 3 and 7 days following injury was associated with a respective 36.5% (HR, 0.63; 95% CI, 0.53-0.76) and 73.2% (HR, 0.27; 95% CI, 0.16-0.45) reduced probability of faster full return to sport compared to within 1 day; and a respective 45.9% (HR, 0.54; 95% CI, 0.44-0.66) and 83.1% (HR, 0.17; 95% CI, 0.10-0.30) reduced probability of faster full return to school/work. Additionally, concussion history, symptom severity, LOC deleteriously influenced concussion recovery. Earlier initiation of aerobic exercise was associated with faster full return to sport and school or work. This study provides greater insight into the benefits and safety of aerobic exercise within the first week of the injury.

  15. Infant malnutrition predicts conduct problems in adolescents

    PubMed Central

    Galler, Janina R.; Bryce, Cyralene P.; Waber, Deborah P.; Hock, Rebecca S.; Harrison, Robert; Eaglesfield, G. David; Fitzmaurice, Garret

    2013-01-01

    Objectives The purpose of this study was to compare the prevalence of conduct problems in a well-documented sample of Barbadian adolescents malnourished as infants and a demographic comparison group and to determine the extent to which cognitive impairment and environmental factors account for this association. Methods Behavioral symptoms were assessed using a 76-item self-report scale in 56 Barbadian youth (11–17 years of age) with histories of protein–energy malnutrition (PEM) limited to the first year of life and 60 healthy classmates. Group comparisons were carried out by longitudinal and cross-sectional multiple regression analyses at 3 time points in childhood and adolescence. Results Self-reported conduct problems were more prevalent among previously malnourished youth (P < 0.01). Childhood IQ and home environmental circumstances partially mediated the association with malnutrition. Teacher-reported classroom behaviors at earlier ages were significantly correlated with youth conduct problems, confirming the continuity of conduct problems through childhood and adolescence. Discussion Self-reported conduct problems are elevated in children and adolescents with histories of early childhood malnutrition. Later vulnerability to increased conduct problems appears to be mediated by the more proximal neurobehavioral effects of the malnutrition on cognitive function and by adverse conditions in the early home environment. PMID:22584048

  16. Infant malnutrition predicts conduct problems in adolescents.

    PubMed

    Galler, Janina R; Bryce, Cyralene P; Waber, Deborah P; Hock, Rebecca S; Harrison, Robert; Eaglesfield, G David; Fitzmaurice, Garret

    2012-07-01

    The purpose of this study was to compare the prevalence of conduct problems in a well-documented sample of Barbadian adolescents malnourished as infants and a demographic comparison group and to determine the extent to which cognitive impairment and environmental factors account for this association. Behavioral symptoms were assessed using a 76-item self-report scale in 56 Barbadian youth (11-17 years of age) with histories of protein-energy malnutrition (PEM) limited to the first year of life and 60 healthy classmates. Group comparisons were carried out by longitudinal and cross-sectional multiple regression analyses at 3 time points in childhood and adolescence. Self-reported conduct problems were more prevalent among previously malnourished youth (P < 0.01). Childhood IQ and home environmental circumstances partially mediated the association with malnutrition. Teacher-reported classroom behaviors at earlier ages were significantly correlated with youth conduct problems, confirming the continuity of conduct problems through childhood and adolescence. Self-reported conduct problems are elevated in children and adolescents with histories of early childhood malnutrition. Later vulnerability to increased conduct problems appears to be mediated by the more proximal neurobehavioral effects of the malnutrition on cognitive function and by adverse conditions in the early home environment.

  17. Comprehensive methods for earlier detection and monitoring of forest decline

    Treesearch

    Jennifer Pontius; Richard Hallett

    2014-01-01

    Forested ecosystems are threatened by invasive pests, pathogens, and unusual climatic events brought about by climate change. Earlier detection of incipient forest health problems and a quantitatively rigorous assessment method is increasingly important. Here, we describe a method that is adaptable across tree species and stress agents and practical for use in the...

  18. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Conduct of a study. 160.130 Section... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study... conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date of...

  19. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Conduct of a study. 160.130 Section... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study... conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date of...

  20. A vantage from space can detect earlier drought onset: an approach using relative humidity.

    PubMed

    Farahmand, Alireza; AghaKouchak, Amir; Teixeira, Joao

    2015-02-25

    Each year, droughts cause significant economic and agricultural losses across the world. The early warning and onset detection of drought is of particular importance for effective agriculture and water resource management. Previous studies show that the Standard Precipitation Index (SPI), a measure of precipitation deficit, detects drought onset earlier than other indicators. Here we show that satellite-based near surface air relative humidity data can further improve drought onset detection and early warning. This paper introduces the Standardized Relative Humidity Index (SRHI) based on the NASA Atmospheric Infrared Sounder (AIRS) observations. The results indicate that the SRHI typically detects the drought onset earlier than the SPI. While the AIRS mission was not originally designed for drought monitoring, we show that its relative humidity data offers a new and unique avenue for drought monitoring and early warning. We conclude that the early warning aspects of SRHI may have merit for integration into current drought monitoring systems.

  1. A Vantage from Space Can Detect Earlier Drought Onset: An Approach Using Relative Humidity

    PubMed Central

    Farahmand, Alireza; AghaKouchak, Amir; Teixeira, Joao

    2015-01-01

    Each year, droughts cause significant economic and agricultural losses across the world. The early warning and onset detection of drought is of particular importance for effective agriculture and water resource management. Previous studies show that the Standard Precipitation Index (SPI), a measure of precipitation deficit, detects drought onset earlier than other indicators. Here we show that satellite-based near surface air relative humidity data can further improve drought onset detection and early warning. This paper introduces the Standardized Relative Humidity Index (SRHI) based on the NASA Atmospheric Infrared Sounder (AIRS) observations. The results indicate that the SRHI typically detects the drought onset earlier than the SPI. While the AIRS mission was not originally designed for drought monitoring, we show that its relative humidity data offers a new and unique avenue for drought monitoring and early warning. We conclude that the early warning aspects of SRHI may have merit for integration into current drought monitoring systems. PMID:25711500

  2. Earlier Violent Television Exposure and Later Drug Dependence

    PubMed Central

    Brook, David W.; Katten, Naomi S.; Ning, Yuming; Brook, Judith S.

    2013-01-01

    This research examined the longitudinal pathways from earlier violent television exposure to later drug dependence. African American and Puerto Rican adolescents were interviewed during three points in time (N = 463). Violent television exposure in late adolescence predicted violent television exposure in young adulthood, which in turn was related to tobacco/marijuana use, nicotine dependence, and later drug dependence. Some policy and clinical implications suggest: a) regulating the times when violent television is broadcast; b) creating developmentally targeted prevention/treatment programs; and c) recognizing that watching violent television may serve as a cue regarding increased susceptibility to nicotine and drug dependence. PMID:18612881

  3. Higher Childhood Red Meat Intake Frequency Is Associated with Earlier Age at Menarche.

    PubMed

    Jansen, Erica C; Marín, Constanza; Mora-Plazas, Mercedes; Villamor, Eduardo

    2016-03-09

    Early age at menarche is associated with increased breast cancer risk. Red meat consumption in adolescence predicts breast cancer risk, but it is unknown whether it is also related to earlier menarche. We studied the association between intake of red meat at ages 5-12 y and age at menarche in a prospective study. We assessed usual diets with a food-frequency questionnaire in a group of 456 girls aged 8.4 ± 1.7 y and followed them for a median 5.6 y in Bogotá, Colombia. Girls were asked periodically about the occurrence and date of menarche. Median age at menarche was estimated with use of Kaplan-Meier survival probabilities by categories of red meat intake frequency. Cox proportional hazards models were used to compare the incidence of menarche by red meat intake frequency, adjusting for potential sociodemographic and dietary confounders including total energy intake and intake frequency of other animal food groups (dairy, poultry, freshwater fish, tuna/sardines, eggs, and innards). Median age at menarche was 12.4 y. After adjustment for total energy intake, maternal parity, and socioeconomic status, red meat intake frequency was inversely associated with age at menarche. When compared with girls with red meat intake <4 times/wk, those consuming it ≥2 times/d had a significantly earlier age at menarche (HR: 1.64; 95% CI: 1.11, 2.41; P-trend = 0.0009). Incidentally, we found that girls with tuna/sardine intake >1 time/wk had a significantly later age at menarche (HR: 0.62; 95% CI: 0.42, 0.90; P = 0.01) than those with intake <1 time/mo. Intake frequency of other animal food groups was not significantly associated with age at menarche. Higher red meat intake frequency during childhood is associated with an earlier age at menarche, whereas greater fatty fish intake frequency is associated with a later menarcheal age. © 2016 American Society for Nutrition.

  4. Switching of the electrical conductivity of plasticized PVC films under uniaxial pressure

    NASA Astrophysics Data System (ADS)

    Vlasov, D. V.; Apresyan, L. A.; Vlasova, T. V.; Kryshtob, V. I.

    2011-11-01

    The jumplike switching of the electrical conductivity in wide-band-gap polymer (antistatic plasticized polyvinylchloride) films under uniaxial pressure is studied. In various plasticized PVC materials, the uniaxial pressure inducing a conductivity jump by four orders of magnitude or higher changes from several to several hundreds of bars, and this effect is retained at a film thickness of several hundred microns, which is two orders of magnitude larger than the critical film thicknesses known for other wide-band-gap polymers. In addition to the earlier interpretation of the conductivity anomalies in plasticized PVC, we proposed a phenomenological electron-molecular dynamic nanotrap model, in which local charge transfer is provided by mobile molecule segments in a plasticized polymer.

  5. Earlier time to aerobic exercise is associated with faster recovery following acute sport concussion

    PubMed Central

    Richards, Doug; Comper, Paul; Hutchison, Michael G.

    2018-01-01

    Objective To determine whether earlier time to initiation of aerobic exercise following acute concussion is associated with time to full return to (1) sport and (2) school or work. Methods A retrospective stratified propensity score survival analysis of acute (≤14 days) concussion was used to determine whether time (days) to initiation of aerobic exercise post-concussion was associated with, both, time (days) to full return to (1) sport and (2) school or work. Results A total of 253 acute concussions [median (IQR) age, 17.0 (15.0–20.0) years; 148 (58.5%) males] were included in this study. Multivariate Cox regression models identified that earlier time to aerobic exercise was associated with faster return to sport and school/work adjusting for other covariates, including quintile propensity strata. For each successive day in delay to initiation of aerobic exercise, individuals had a less favourable recovery trajectory. Initiating aerobic exercise at 3 and 7 days following injury was associated with a respective 36.5% (HR, 0.63; 95% CI, 0.53–0.76) and 73.2% (HR, 0.27; 95% CI, 0.16–0.45) reduced probability of faster full return to sport compared to within 1 day; and a respective 45.9% (HR, 0.54; 95% CI, 0.44–0.66) and 83.1% (HR, 0.17; 95% CI, 0.10–0.30) reduced probability of faster full return to school/work. Additionally, concussion history, symptom severity, LOC deleteriously influenced concussion recovery. Conclusion Earlier initiation of aerobic exercise was associated with faster full return to sport and school or work. This study provides greater insight into the benefits and safety of aerobic exercise within the first week of the injury. PMID:29668716

  6. A Review of Quality of Life after Predictive Testing for and Earlier Identification of Neurodegenerative Diseases

    PubMed Central

    Paulsen, Jane S.; Nance, Martha; Kim, Ji-In; Carlozzi, Noelle E.; Panegyres, Peter K.; Erwin, Cheryl; Goh, Anita; McCusker, Elizabeth; Williams, Janet K.

    2013-01-01

    The past decade has witnessed an explosion of evidence suggesting that many neurodegenerative diseases can be detected years, if not decades, earlier than previously thought. To date, these scientific advances have not provoked any parallel translational or clinical improvements. There is an urgency to capitalize on this momentum so earlier detection of disease can be more readily translated into improved health-related quality of life for families at risk for, or suffering with, neurodegenerative diseases. In this review, we discuss health-related quality of life (HRQOL) measurement in neurodegenerative diseases and the importance of these “patient reported outcomes” for all clinical research. Next, we address HRQOL following early identification or predictive genetic testing in some neurodegenerative diseases: Huntington disease, Alzheimer's disease, Parkinson's disease, Dementia with Lewy bodies, frontotemporal dementia, amyotrophic lateral sclerosis, prion diseases, hereditary ataxias, Dentatorubral-pallidoluysian atrophy and Wilson's disease. After a brief report of available direct-to-consumer genetic tests, we address the juxtaposition of earlier disease identification with assumed reluctance towards predictive genetic testing. Forty-one studies examining health related outcomes following predictive genetic testing for neurodegenerative disease suggested that (a) extreme or catastrophic outcomes are rare; (b) consequences commonly include transiently increased anxiety and/or depression; (c) most participants report no regret; (d) many persons report extensive benefits to receiving genetic information; and (e) stigmatization and discrimination for genetic diseases are poorly understood and policy and laws are needed. Caution is appropriate for earlier identification of neurodegenerative diseases but findings suggest further progress is safe, feasible and likely to advance clinical care. PMID:24036231

  7. Economic Costs Avoided by Diagnosing Melanoma Six Months Earlier Justify >100 Benign Biopsies.

    PubMed

    Aires, Daniel J; Wick, Jo; Shaath, Tarek S; Rajpara, Anand N; Patel, Vikas; Badawi, Ahmed H; Li, Cicy; Fraga, Garth R; Doolittle, Gary; Liu, Deede Y

    2016-05-01

    New melanoma drugs bring enormous benefits but do so at significant costs. Because melanoma grows deeper and deadlier over time, deeper lesions are costlier due to increased sentinel lymph node biopsy, chemotherapy, and disease-associated income loss. Prior studies have justified pigmented lesion biopsies on a "value per life" basis; by contrast we sought to assess how many biopsies are justified per melanoma found on a purely economic basis. We modeled how melanomas in the United States would behave if diagnosis were delayed by 6 months, eg, not biopsied, only observed until the next surveillance visit. Economic loss from delayed biopsy is the obverse of economic benefit of performing biopsy earlier. Growth rates were based on Liu et al. The results of this study can be applied to all patients presenting to dermatologists with pigmented skin lesions suspicious for melanoma. In-situ melanomas were excluded because no studies to date have modeled growth rates analogous to those for invasive melanoma. We assume conservatively that all melanomas not biopsied initially will be biopsied and treated 6 months later. Major modeled costs are (1) increased sentinel lymph node biopsy, (2) increased chemotherapy for metastatic lesions using increased 5-yr death as metastasis marker, and (3) income loss per melanoma death at $413,370 as previously published. Costs avoided by diagnosing melanoma earlier justify 170 biopsies per melanoma found. Efforts to penalize "unnecessary" biopsies may be economically counterproductive.

    J Drugs Dermatol. 2016;15(5):527-532.

  8. Ion Conduction in Perfectly Aligned Block Copolymer-Ionic Liquid Mixtures

    NASA Astrophysics Data System (ADS)

    Choi, Jae-Hong; Elabd, Yossef A.; Winey, Karen I.

    2011-03-01

    Our earlier work to correlate the transport measurements in diblock copolymer-ionic liquid mixtures was limited by our bulk samples that have only partial alignment. Here, thin films with perfect alignment of lamellar microdomains from mixtures of a poly(methyl methacrylate- b -styrene) diblock copolymer and an ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, have been studied. The morphologies will be characterized by cross-sectional transmission electron microscopy. Ion conduction will be presented within and through the thin film.

  9. Traumatic brain injury history is associated with an earlier age of dementia onset in autopsy-confirmed Alzheimer's disease.

    PubMed

    Schaffert, Jeff; LoBue, Christian; White, Charles L; Chiang, Hsueh-Sheng; Didehbani, Nyaz; Lacritz, Laura; Rossetti, Heidi; Dieppa, Marisara; Hart, John; Cullum, C Munro

    2018-05-01

    To evaluate whether a history of traumatic brain injury (TBI) with reported loss of consciousness (LOC) is a risk factor for earlier onset of Alzheimer's disease (AD) in an autopsy-confirmed sample. Data from 2,133 participants with autopsy-confirmed AD (i.e., at least Braak neurofibrillary tangle stages III to VI and CERAD neuritic plaque score moderate to frequent) were obtained from the National Alzheimer's Coordinating Center (NACC). Participants were categorized by presence/absence of self-reported remote (i.e., >1 year prior to their first Alzheimer's Disease Center visit) history of TBI with LOC (TBI+ vs. TBI-). Analyses of Covariance (ANCOVA) controlling for sex, education, and race compared groups on clinician-estimated age of symptom onset and age of diagnosis. Average age of onset was 2.34 years earlier (p = .01) for the TBI+ group (n = 194) versus the TBI- group (n = 1900). Dementia was diagnosed on average 2.83 years earlier (p = .002) in the TBI+ group (n = 197) versus the TBI- group (n = 1936). Using more stringent neuropathological criteria (i.e., Braak stages V-VI and CERAD frequent), both age of AD onset and diagnosis were 3.6 years earlier in the TBI+ group (both p's < .001). History of TBI with reported LOC appears to be a risk factor for earlier AD onset. This is the first study to use autopsy-confirmed cases, supporting previous investigations that used clinical criteria for the diagnosis of AD. Further investigation as to possible underlying mechanisms of association is needed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  10. Identifying pneumonia outbreaks of public health importance: can emergency department data assist in earlier identification?

    PubMed

    Hope, Kirsty; Durrheim, David N; Muscatello, David; Merritt, Tony; Zheng, Wei; Massey, Peter; Cashman, Patrick; Eastwood, Keith

    2008-08-01

    To retrospectively review the performance of a near real-time Emergency Department (ED) Syndromic Surveillance System operating in New South Wales for identifying pneumonia outbreaks of public health importance. Retrospective data was obtained from the NSW Emergency Department data collection for a rural hospital that has experienced a cluster of pneumonia diagnoses among teenage males in August 2006. ED standard reports were examined for signals in the overall count for each respiratory syndrome, and for elevated counts in individual subgroups including; age, sex and admission to hospital status. Using the current thresholds, the ED syndromic surveillance system would have trigged a signal for pneumonia syndrome in children aged 5-16 years four days earlier than the notification by a paediatrician and this signal was maintained for 14 days. If the ED syndromic surveillance system had been operating it could have identified the outbreak earlier than the paediatrician's notification. This may have permitted an earlier public health response. By understanding the behaviour of syndromes during outbreaks of public health importance, response protocols could be developed to facilitate earlier implementation of control measures.

  11. Earlier nesting by generalist predatory bird is associated with human responses to climate change.

    PubMed

    Smith, Shawn H; Steenhof, Karen; McClure, Christopher J W; Heath, Julie A

    2017-01-01

    Warming temperatures cause temporal changes in growing seasons and prey abundance that drive earlier breeding by birds, especially dietary specialists within homogeneous habitat. Less is known about how generalists respond to climate-associated shifts in growing seasons or prey phenology, which may occur at different rates across land cover types. We studied whether breeding phenology of a generalist predator, the American kestrel (Falco sparverius), was associated with shifts in growing seasons and, presumably, prey abundance, in a mosaic of non-irrigated shrub/grasslands and irrigated crops/pastures. We examined the relationship between remotely-sensed normalized difference vegetation index (NDVI) and abundance of small mammals that, with insects, constitute approximately 93% of kestrel diet biomass. We used NDVI to estimate the start of the growing season (SoGS) in irrigated and non-irrigated lands from 1992 to 2015 and tested whether either estimate of annual SoGS predicted the timing of kestrel nesting. Finally, we examined relationships among irrigated SoGS, weather and crop planting. NDVI was a useful proxy for kestrel prey because it predicted small mammal abundance and past studies showed that NDVI predicts insect abundance. NDVI-estimated SoGS advanced significantly in irrigated lands (β = -1·09 ± 0·30 SE) but not in non-irrigated lands (β = -0·57 ± 0·53). Average date of kestrel nesting advanced 15 days in the past 24 years and was positively associated with the SoGS in irrigated lands, but not the SoGS in non-irrigated lands. Advanced SoGS in irrigated lands was related to earlier planting of crops after relatively warm winters, which were more common in recent years. Despite different patterns of SoGS change between land cover types, kestrel nesting phenology shifted with earlier prey availability in irrigated lands. Kestrels may preferentially track prey in irrigated lands over non-irrigated lands because of higher quality prey on

  12. Earlier vegetation green-up has reduced spring dust storms

    PubMed Central

    Fan, Bihang; Guo, Li; Li, Ning; Chen, Jin; Lin, Henry; Zhang, Xiaoyang; Shen, Miaogen; Rao, Yuhan; Wang, Cong; Ma, Lei

    2014-01-01

    The observed decline of spring dust storms in Northeast Asia since the 1950s has been attributed to surface wind stilling. However, spring vegetation growth could also restrain dust storms through accumulating aboveground biomass and increasing surface roughness. To investigate the impacts of vegetation spring growth on dust storms, we examine the relationships between recorded spring dust storm outbreaks and satellite-derived vegetation green-up date in Inner Mongolia, Northern China from 1982 to 2008. We find a significant dampening effect of advanced vegetation growth on spring dust storms (r = 0.49, p = 0.01), with a one-day earlier green-up date corresponding to a decrease in annual spring dust storm outbreaks by 3%. Moreover, the higher correlation (r = 0.55, p < 0.01) between green-up date and dust storm outbreak ratio (the ratio of dust storm outbreaks to times of strong wind events) indicates that such effect is independent of changes in surface wind. Spatially, a negative correlation is detected between areas with advanced green-up dates and regional annual spring dust storms (r = −0.49, p = 0.01). This new insight is valuable for understanding dust storms dynamics under the changing climate. Our findings suggest that dust storms in Inner Mongolia will be further mitigated by the projected earlier vegetation green-up in the warming world. PMID:25343265

  13. Changes toward earlier streamflow timing across western North America

    USGS Publications Warehouse

    Stewart, I.T.; Cayan, D.R.; Dettinger, M.D.

    2005-01-01

    The highly variable timing of streamflow in snowmelt-dominated basins across western North America is an important consequence, and indicator, of climate fluctuations. Changes in the timing of snowmelt-derived streamflow from 1948 to 2002 were investigated in a network of 302 western North America gauges by examining the center of mass for flow, spring pulse onset dates, and seasonal fractional flows through trend and principal component analyses. Statistical analysis of the streamflow timing measures with Pacific climate indicators identified local and key large-scale processes that govern the regionally coherent parts of the changes and their relative importance. Widespread and regionally coherent trends toward earlier onsets of springtime snowmelt and streamflow have taken place across most of western North America, affecting an area that is much larger than previously recognized. These timing changes have resulted in increasing fractions of annual flow occurring earlier in the water year by 1-4 weeks. The immediate (or proximal) forcings for the spatially coherent parts of the year-to-year fluctuations and longer-term trends of streamflow timing have been higher winter and spring temperatures. Although these temperature changes are partly controlled by the decadal-scale Pacific climate mode [Pacific decadal oscillation (PDO)], a separate and significant part of the variance is associated with a springtime warming trend that spans the PDO phases. ?? 2005 American Meteorological Society.

  14. Earlier vegetation green-up has reduced spring dust storms.

    PubMed

    Fan, Bihang; Guo, Li; Li, Ning; Chen, Jin; Lin, Henry; Zhang, Xiaoyang; Shen, Miaogen; Rao, Yuhan; Wang, Cong; Ma, Lei

    2014-10-24

    The observed decline of spring dust storms in Northeast Asia since the 1950s has been attributed to surface wind stilling. However, spring vegetation growth could also restrain dust storms through accumulating aboveground biomass and increasing surface roughness. To investigate the impacts of vegetation spring growth on dust storms, we examine the relationships between recorded spring dust storm outbreaks and satellite-derived vegetation green-up date in Inner Mongolia, Northern China from 1982 to 2008. We find a significant dampening effect of advanced vegetation growth on spring dust storms (r = 0.49, p = 0.01), with a one-day earlier green-up date corresponding to a decrease in annual spring dust storm outbreaks by 3%. Moreover, the higher correlation (r = 0.55, p < 0.01) between green-up date and dust storm outbreak ratio (the ratio of dust storm outbreaks to times of strong wind events) indicates that such effect is independent of changes in surface wind. Spatially, a negative correlation is detected between areas with advanced green-up dates and regional annual spring dust storms (r = -0.49, p = 0.01). This new insight is valuable for understanding dust storms dynamics under the changing climate. Our findings suggest that dust storms in Inner Mongolia will be further mitigated by the projected earlier vegetation green-up in the warming world.

  15. Earlier tachycardia onset in right than left mesial temporal lobe seizures.

    PubMed

    Kato, Kazuhiro; Jin, Kazutaka; Itabashi, Hisashi; Iwasaki, Masaki; Kakisaka, Yosuke; Aoki, Masashi; Nakasato, Nobukazu

    2014-10-07

    To clarify whether the presence and timing of peri-ictal heart rate (HR) change is a seizure lateralizing sign in patients with mesial temporal lobe epilepsy (mTLE). Long-term video EEGs were retrospectively reviewed in 21 patients, 7 men and 14 women aged 13 to 67 years, diagnosed as mTLE with MRI lesions in the mesial temporal structures (hippocampal sclerosis in 20 cases, amygdala hypertrophy in 1 case). Seventy-seven partial seizures without secondary generalization were extracted. Peri-ictal HR change was compared between 29 right seizures (9 patients) and 48 left seizures (12 patients). HR abruptly increased in all 29 right seizures and 42 of 48 left seizures. Onset time of HR increase in relation to ictal EEG onset was significantly earlier in right seizures than in left seizures (mean ± SD, -11.5 ± 14.8 vs 9.2 ± 21.7 seconds; p < 0.0001). Time of maximum HR was also significantly earlier in right seizures than in left seizures (36.0 ± 18.1 vs 58.0 ± 28.7 seconds; p < 0.0001). Maximum HR changes from baseline showed no significant difference between right and left seizures (47.5 ± 19.1 vs 40.8 ± 20.0/min). Significantly earlier tachycardia in right than left mTLE seizures supports previous hypotheses that the right cerebral hemisphere is dominant in the sympathetic network. No HR change, or delayed tachycardia possibly due to seizure propagation to the right hemisphere, may be a useful lateralizing sign of left mTLE seizures. © 2014 American Academy of Neurology.

  16. Earlier surgical intervention in congenital heart disease results in better outcome and resource utilization.

    PubMed

    Panni, Roheena Z; Ashfaq, Awais; Amanullah, Muhammad M

    2011-12-29

    Congenital heart disease (CHD) accounts for a major proportion of disease in the pediatric age group. The objective of the study was to estimate the cost of illness associated with CHD pre, intra and postoperatively; among patients referred to a tertiary care hospital in Karachi, Pakistan. This is the first study conducted to estimate the cost of managing CHD in Pakistan. A prevalence based cost of illness study design was used to estimate the cost of cardiac surgery (corrective & palliative) for congenital heart defects in children ≤ 5 years of age from June 2006 to June 2009. A total of 120 patients were enrolled after obtaining an informed consent and the data was collected using a pre-tested questionnaire. The mean age at the time of surgery in group A (1-12 mo age) was 6.08 ± 2.80 months and in group B (1-5 yrs) was 37.10 ± 19.94 months. The cost of surgical admission was found to be significantly higher in the older group, p = 0.001. The total number and cost of post-operative outpatient visits was also higher in group B, p = 0.003. Pre and post operative hospital admissions were not found to be significantly different among the two groups, p = 0.166 and 0.627, respectively. The number of complications were found to be different between the two groups (p = 0.019). Majority of these were contributed by hemorrhage and post-operative seizures. This study concluded that significant expenditure is incurred by people with CHD; with the implication that resources could be saved by earlier detection and awareness campaigns.

  17. Identified research directions for using manufacturing knowledge earlier in the product lifecycle

    PubMed Central

    Hedberg, Thomas D.; Hartman, Nathan W.; Rosche, Phil; Fischer, Kevin

    2016-01-01

    Design for Manufacturing (DFM), especially the use of manufacturing knowledge to support design decisions, has received attention in the academic domain. However, industry practice has not been studied enough to provide solutions that are mature for industry. The current state of the art for DFM is often rule-based functionality within Computer-Aided Design (CAD) systems that enforce specific design requirements. That rule-based functionality may or may not dynamically affect geometry definition. And, if rule-based functionality exists in the CAD system, it is typically a customization on a case-by-case basis. Manufacturing knowledge is a phrase with vast meanings, which may include knowledge on the effects of material properties decisions, machine and process capabilities, or understanding the unintended consequences of design decisions on manufacturing. One of the DFM questions to answer is how can manufacturing knowledge, depending on its definition, be used earlier in the product lifecycle to enable a more collaborative development environment? This paper will discuss the results of a workshop on manufacturing knowledge that highlights several research questions needing more study. This paper proposes recommendations for investigating the relationship of manufacturing knowledge with shape, behavior, and context characteristics of product to produce a better understanding of what knowledge is most important. In addition, the proposal includes recommendations for investigating the system-level barriers to reusing manufacturing knowledge and how model-based manufacturing may ease the burden of knowledge sharing. Lastly, the proposal addresses the direction of future research for holistic solutions of using manufacturing knowledge earlier in the product lifecycle. PMID:27990027

  18. Identified research directions for using manufacturing knowledge earlier in the product lifecycle.

    PubMed

    Hedberg, Thomas D; Hartman, Nathan W; Rosche, Phil; Fischer, Kevin

    2017-01-01

    Design for Manufacturing (DFM), especially the use of manufacturing knowledge to support design decisions, has received attention in the academic domain. However, industry practice has not been studied enough to provide solutions that are mature for industry. The current state of the art for DFM is often rule-based functionality within Computer-Aided Design (CAD) systems that enforce specific design requirements. That rule-based functionality may or may not dynamically affect geometry definition. And, if rule-based functionality exists in the CAD system, it is typically a customization on a case-by-case basis. Manufacturing knowledge is a phrase with vast meanings, which may include knowledge on the effects of material properties decisions, machine and process capabilities, or understanding the unintended consequences of design decisions on manufacturing. One of the DFM questions to answer is how can manufacturing knowledge, depending on its definition, be used earlier in the product lifecycle to enable a more collaborative development environment? This paper will discuss the results of a workshop on manufacturing knowledge that highlights several research questions needing more study. This paper proposes recommendations for investigating the relationship of manufacturing knowledge with shape, behavior, and context characteristics of product to produce a better understanding of what knowledge is most important. In addition, the proposal includes recommendations for investigating the system-level barriers to reusing manufacturing knowledge and how model-based manufacturing may ease the burden of knowledge sharing. Lastly, the proposal addresses the direction of future research for holistic solutions of using manufacturing knowledge earlier in the product lifecycle.

  19. Light pollution is associated with earlier tree budburst across the United Kingdom.

    PubMed

    Ffrench-Constant, Richard H; Somers-Yeates, Robin; Bennie, Jonathan; Economou, Theodoros; Hodgson, David; Spalding, Adrian; McGregor, Peter K

    2016-06-29

    The ecological impact of night-time lighting is of concern because of its well-demonstrated effects on animal behaviour. However, the potential of light pollution to change plant phenology and its corresponding knock-on effects on associated herbivores are less clear. Here, we test if artificial lighting can advance the timing of budburst in trees. We took a UK-wide 13 year dataset of spatially referenced budburst data from four deciduous tree species and matched it with both satellite imagery of night-time lighting and average spring temperature. We find that budburst occurs up to 7.5 days earlier in brighter areas, with the relationship being more pronounced for later-budding species. Excluding large urban areas from the analysis showed an even more pronounced advance of budburst, confirming that the urban 'heat-island' effect is not the sole cause of earlier urban budburst. Similarly, the advance in budburst across all sites is too large to be explained by increases in temperature alone. This dramatic advance of budburst illustrates the need for further experimental investigation into the impact of artificial night-time lighting on plant phenology and subsequent species interactions. As light pollution is a growing global phenomenon, the findings of this study are likely to be applicable to a wide range of species interactions across the world. © 2016 The Authors.

  20. Recent gestational diabetes was associated with mothers stopping predominant breastfeeding earlier in a multi-ethnic population.

    PubMed

    Baerug, Anne; Sletner, Line; Laake, Petter; Fretheim, Atle; Løland, Beate Fossum; Waage, Christin W; Birkeland, Kåre I; Jenum, Anne Karen

    2018-06-01

    It has previously been shown that breastfeeding may reduce the risk of type 2 diabetes in mothers with recent gestational diabetes mellitus (GDM). This study compared the cessation of predominant breastfeeding in mothers with and without recent GDM in a multi-ethnic population. From May 2008 to May 2010, healthy pregnant women attending antenatal care provided by community health services in Eastern Oslo, Norway were recruited. We included 616 women-58% non-Western-and interviewed and examined them at a mean of 15 and 28 weeks of gestation and 14 weeks' postpartum. Cox regression models examined the association between GDM, as assessed by the 2013 World Health Organization criteria, and breastfeeding cessation. Overall, 190 of the 616 (31%) mothers had GDM and they ended predominant breastfeeding earlier than mothers without GDM, with an adjusted hazard ratio (aHR) of 1.33 and 95% confidence interval (95% CI) of 1.01-1.77. Mothers of South Asian origin ended predominant breastfeeding earlier than Western European mothers in the adjusted analysis (aHR 1.53, 95% CI: 1.04-2.25), but Middle Eastern mothers did not. Recent gestational diabetes was associated with earlier cessation of predominant breastfeeding in Western European and non-Western women. ©2018 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  1. To achieve an earlier IFN-γ response is not sufficient to control Mycobacterium tuberculosis infection in mice.

    PubMed

    Vilaplana, Cristina; Prats, Clara; Marzo, Elena; Barril, Carles; Vegué, Marina; Diaz, Jorge; Valls, Joaquim; López, Daniel; Cardona, Pere-Joan

    2014-01-01

    The temporo-spatial relationship between the three organs (lung, spleen and lymph node) involved during the initial stages of Mycobacterium tuberculosis infection has been poorly studied. As such, we performed an experimental study to evaluate the bacillary load in each organ after aerosol or intravenous infection and developed a mathematical approach using the data obtained in order to extract conclusions. The results showed that higher bacillary doses result in an earlier IFN-γ response, that a certain bacillary load (BL) needs to be reached to trigger the IFN-γ response, and that control of the BL is not immediate after onset of the IFN-γ response, which might be a consequence of the spatial dimension. This study may have an important impact when it comes to designing new vaccine candidates as it suggests that triggering an earlier IFN-γ response might not guarantee good infection control, and therefore that additional properties should be considered for these candidates.

  2. To Achieve an Earlier IFN-γ Response Is Not Sufficient to Control Mycobacterium tuberculosis Infection in Mice

    PubMed Central

    Marzo, Elena; Barril, Carles; Vegué, Marina; Diaz, Jorge; Valls, Joaquim; López, Daniel; Cardona, Pere-Joan

    2014-01-01

    The temporo-spatial relationship between the three organs (lung, spleen and lymph node) involved during the initial stages of Mycobacterium tuberculosis infection has been poorly studied. As such, we performed an experimental study to evaluate the bacillary load in each organ after aerosol or intravenous infection and developed a mathematical approach using the data obtained in order to extract conclusions. The results showed that higher bacillary doses result in an earlier IFN-γ response, that a certain bacillary load (BL) needs to be reached to trigger the IFN-γ response, and that control of the BL is not immediate after onset of the IFN-γ response, which might be a consequence of the spatial dimension. This study may have an important impact when it comes to designing new vaccine candidates as it suggests that triggering an earlier IFN-γ response might not guarantee good infection control, and therefore that additional properties should be considered for these candidates. PMID:24959669

  3. The association between cannabis use and earlier age at onset of schizophrenia and other psychoses: meta-analysis of possible confounding factors.

    PubMed

    Myles, Nicholas; Newall, Hannah; Nielssen, Olav; Large, Matthew

    2012-01-01

    A recent meta-analysis showed that the mean age of onset of psychosis among cannabis users was almost three years earlier than that of non-cannabis users. However, because cannabis users usually smoke tobacco, the use of tobacco might independently contribute to the earlier onset of psychosis. We aimed to use meta-analysis to compare the extent to which cannabis and tobacco use are each associated with an earlier age at onset of schizophrenia and other psychoses. We also examined other factors that might have contributed to the finding of an earlier age of onset among cannabis users, including the proportion of males in the samples, the diagnostic inclusion criteria and aspects of study quality. The electronic databases MEDLINE, EMBASE, PsycINFO and ISI Web of Science, were searched for English-language peer-reviewed publications that reported age at onset of schizophrenia and other psychoses separately for cannabis users and non-users, or for tobaccosmokers and non-smokers. Meta-analysis showed that the age at onset of psychosis for cannabis users was 32 months earlier than for cannabis non-users (SMD=- 0.399, 95%CI -0.493 - -0.306, z=-8.34, p < 0.001), and was two weeks later in tobacco smokers compared with non-smokers (SMD=0.002, 95%CI -0.094 - 0.097, z=0.03, p=0.974). The main results were not affected by subgroup analyses examining studies of a single sex, the methods for making psychiatric diagnoses and measures of study quality. The results suggest that the association between cannabis use and earlier onset of psychosis is robust and is not the result either of tobacco smoking by cannabis using patients or the other potentially confounding factors we examined. This supports the hypothesis that, in some patients, cannabis use plays a causal role in the development of schizophrenia and raises the possibility of treating schizophrenia with new pharmacological treatments that have an affinity for endo-cannabinoid receptors.

  4. Visual ecology and potassium conductances of insect photoreceptors.

    PubMed

    Frolov, Roman; Immonen, Esa-Ville; Weckström, Matti

    2016-04-01

    Voltage-activated potassium channels (Kv channels) in the microvillar photoreceptors of arthropods are responsible for repolarization and regulation of photoreceptor signaling bandwidth. On the basis of analyzing Kv channels in dipteran flies, it was suggested that diurnal, rapidly flying insects predominantly express sustained K(+) conductances, whereas crepuscular and nocturnally active animals exhibit strongly inactivating Kv conductances. The latter was suggested to function for minimizing cellular energy consumption. In this study we further explore the evolutionary adaptations of the photoreceptor channelome to visual ecology and behavior by comparing K(+) conductances in 15 phylogenetically diverse insects, using patch-clamp recordings from dissociated ommatidia. We show that rapid diurnal flyers such as the blowfly (Calliphora vicina) and the honeybee (Apis mellifera) express relatively large noninactivating Kv conductances, conforming to the earlier hypothesis in Diptera. Nocturnal and/or slow-moving species do not in general exhibit stronger Kv conductance inactivation in the physiological membrane voltage range, but the photoreceptors in species that are known to rely more on vision behaviorally had higher densities of sustained Kv conductances than photoreceptors of less visually guided species. No statistically significant trends related to visual performance could be identified for the rapidly inactivating Kv conductances. Counterintuitively, strong negative correlations were observed between photoreceptor capacitance and specific membrane conductance for both sustained and inactivating fractions of Kv conductance, suggesting insignificant evolutionary pressure to offset negative effects of high capacitance on membrane filtering with increased conductance. Copyright © 2016 the American Physiological Society.

  5. Earlier and greater hand pre-shaping in the elderly: a study based on kinematic analysis of reaching movements to grasp objects.

    PubMed

    Tamaru, Yoshiki; Naito, Yasuo; Nishikawa, Takashi

    2017-11-01

    Elderly people are less able to manipulate objects skilfully than young adults. Although previous studies have examined age-related deterioration of hand movements with a focus on the phase after grasping objects, the changes in the reaching phase have not been studied thus far. We aimed to examine whether changes in hand shape patterns during the reaching phase of grasping movements differ between young adults and the elderly. Ten healthy elderly adults and 10 healthy young adults were examined using the Simple Test for Evaluating Hand Functions and kinetic analysis of hand pre-shaping reach-to-grasp tasks. The results were then compared between the two groups. For kinetic analysis, we measured the time of peak tangential velocity of the wrist and the inter-fingertip distance (the distance between the tips of the thumb and index finger) at different time points. The results showed that the elderly group's performance on the Simple Test for Evaluating Hand Functions was significantly lower than that of the young adult group, irrespective of whether the dominant or non-dominant hand was used, indicating deterioration of hand movement in the elderly. The peak tangential velocity of the wrist in either hand appeared significantly earlier in the elderly group than in the young adult group. The elderly group also showed larger inter-fingertip distances with arch-like fingertip trajectories compared to the young adult group for all object sizes. To perform accurate prehension, elderly people have an earlier peak tangential velocity point than young adults. This allows for a longer adjustment time for reaching and grasping movements and for reducing errors in object prehension by opening the hand and fingers wider. Elderly individuals gradually modify their strategy based on previous successes and failures during daily living to compensate for their decline in dexterity and operational capabilities. © 2017 Japanese Psychogeriatric Society.

  6. Increasing Black Hole Feedback-induced Quenching with Anisotropic Thermal Conduction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kannan, Rahul; Vogelsberger, Mark; Pfrommer, Christoph

    Feedback from central supermassive black holes is often invoked to explain the low star formation rates (SFRs) in the massive galaxies at the centers of galaxy clusters. However, the detailed physics of the coupling of the injected feedback energy with the intracluster medium (ICM) is still unclear. Using high-resolution magnetohydrodynamic cosmological simulations of galaxy cluster formation, we investigate the role of anisotropic thermal conduction in shaping the thermodynamic structure of clusters, and in particular, in modifying the impact of black hole feedback. Stratified anisotropically conducting plasmas are formally always unstable, and thus more prone to mixing, an expectation borne outmore » by our results. The increased mixing efficiently isotropizes the injected feedback energy, which in turn significantly improves the coupling between the feedback energy and the ICM. This facilitates an earlier disruption of the cool-core, reduces the SFR by more than an order of magnitude, and results in earlier quenching despite an overall lower amount of feedback energy injected into the cluster core. With conduction, the metallicity gradients and dispersions are lowered, aligning them better with observational constraints. These results highlight the important role of thermal conduction in establishing and maintaining the quiescence of massive galaxies.« less

  7. Spatial and Temporal Variation in Primary Productivity (NDVI) of Coastal Alaskan Tundra: Decreased Vegetation Growth Following Earlier Snowmelt

    NASA Technical Reports Server (NTRS)

    Gamon, John A.; Huemmrich, K. Fred; Stone, Robert S.; Tweedie, Craig E.

    2015-01-01

    In the Arctic, earlier snowmelt and longer growing seasons due to warming have been hypothesized to increase vegetation productivity. Using the Normalized Difference Vegetation Index (NDVI) from both field and satellite measurements as an indicator of vegetation phenology and productivity, we monitored spatial and temporal patterns of vegetation growth for a coastal wet sedge tundra site near Barrow, Alaska over three growing seasons (2000-2002). Contrary to expectation, earlier snowmelt did not lead to increased productivity. Instead, productivity was associated primarily with precipitation and soil moisture, and secondarily with growing degree days, which, during this period, led to reduced growth in years with earlier snowmelt. Additional moisture effects on productivity and species distribution, operating over a longer time scale, were evident in spatial NDVI patterns associated with microtopography. Lower, wetter regions dominated by graminoids were more productive than higher, drier locations having a higher percentage of lichens and mosses, despite the earlier snowmelt at the more elevated sites. These results call into question the oft-stated hypothesis that earlier arctic growing seasons will lead to greater vegetation productivity. Rather, they agree with an emerging body of evidence from recent field studies indicating that early-season, local environmental conditions, notably moisture and temperature, are primary factors determining arctic vegetation productivity. For this coastal arctic site, early growing season conditions are strongly influenced by microtopography, hydrology, and regional sea ice dynamics, and may not be easily predicted from snowmelt date or seasonal average air temperatures alone. Our comparison of field to satellite NDVI also highlights the value of in-situ monitoring of actual vegetation responses using field optical sampling to obtain detailed information on surface conditions not possible from satellite observations alone.

  8. Discharging patients earlier in the day: a concept worth evaluating.

    PubMed

    Kravet, Steven J; Levine, Rachel B; Rubin, Haya R; Wright, Scott M

    2007-01-01

    Patient discharges from the hospital often occur late in the day and are frequently clustered after 4 PM. When inpatients leave earlier in the day, quality is improved because new admissions awaiting beds are able to leave the emergency department sooner and emergency department waiting room backlog is reduced. Nursing staff, whose work patterns traditionally result in high activity of discharge and admission between 5 PM and 8 PM, benefit by spreading out their work across a longer part of the day. Discharging patients earlier in the day also has the potential to increase patient satisfaction. Despite multiple stakeholders in the discharge planning process, physicians play the most important role. Getting physician buy-in requires an ability to teach physicians about the concept of early-in-the-day discharges and their impact on the process. We defined a new physician-centered discharge planning process and introduced it to an internal medicine team with an identical control team as a comparison. Discharge time of day was analyzed for 1 month. Mean time of day of discharge was 13:39 for the intervention group versus 15:45 for the control group (P<.001). If reproduced successfully, this process could improve quality at an important transition point in patient care.

  9. Conducting Simulation Studies in Psychometrics

    ERIC Educational Resources Information Center

    Feinberg, Richard A.; Rubright, Jonathan D.

    2016-01-01

    Simulation studies are fundamental to psychometric discourse and play a crucial role in operational and academic research. Yet, resources for psychometricians interested in conducting simulations are scarce. This Instructional Topics in Educational Measurement Series (ITEMS) module is meant to address this deficiency by providing a comprehensive…

  10. Earlier warning: a multi-indicator approach to monitoring trends in the illicit use of medicines.

    PubMed

    Mounteney, Jane; Haugland, Siren

    2009-03-01

    The availability of medicines on the illicit drug market is currently high on the international policy agenda, linked to adverse health consequences including addiction, drug related overdoses and injection related problems. Continuous surveillance of illicit use of medicines allows for earlier identification and reporting of emerging trends and increased possibilities for earlier intervention to prevent spread of use and drug related harm. This paper aims to identify data sources capable of monitoring the illicit use of medicines; present trend findings for Rohypnol and Subutex using a multi-indicator monitoring approach; and consider the relevance of such models for policy makers. Data collection and analysis were undertaken in Bergen, Norway, using the Bergen Earlier Warning System (BEWS), a multi-indicator drug monitoring system. Data were gathered at six monthly intervals from April 2002 to September 2006. Drug indicator data from seizures, treatment, pharmacy sales, helplines, key informants and media monitoring were triangulated and an aggregated differential was used to plot trends. Results for the 4-year period showed a decline in the illicit use of Rohypnol and an increase in the illicit use of Subutex. Multi-indicator surveillance models can play a strategic role in the earlier identification and reporting of emerging trends in illicit use of medicines.

  11. Garan conducts ISSAC installation in the US Lab

    NASA Image and Video Library

    2011-05-06

    ISS027-E-023657 (6 May 2011) --- NASA astronaut Ron Garan, Expedition 27 flight engineer, works with ISS Agricultural Camera (ISSAC) hardware in the Destiny laboratory of the International Space Station. ISSAC, a successor of the earlier AgCam, will operate in conjunction with EarthKAM, both instruments to conduct simultaneous but independent operations in the WORF rack in Destiny.

  12. Garan conducts ISSAC installation in the US Lab

    NASA Image and Video Library

    2011-05-06

    ISS027-E-023658 (6 May 2011) --- NASA astronaut Ron Garan, Expedition 27 flight engineer, works with ISS Agricultural Camera (ISSAC) hardware in the Destiny laboratory of the International Space Station. ISSAC, a successor of the earlier AgCam, will operate in conjunction with EarthKAM, both instruments to conduct simultaneous but independent operations in the WORF rack in Destiny.

  13. Garan conducts ISSAC installation in the US Lab

    NASA Image and Video Library

    2011-05-06

    ISS027-E-023644 (6 May 2011) --- NASA astronaut Ron Garan, Expedition 27 flight engineer, works with ISS Agricultural Camera (ISSAC) hardware in the Destiny laboratory of the International Space Station. ISSAC, a successor of the earlier AgCam, will operate in conjunction with EarthKAM, both instruments to conduct simultaneous but independent operations in the WORF rack in Destiny.

  14. Garan conducts ISSAC installation in the US Lab

    NASA Image and Video Library

    2011-05-06

    ISS027-E-023655 (6 May 2011) --- NASA astronaut Ron Garan, Expedition 27 flight engineer, works with ISS Agricultural Camera (ISSAC) hardware in the Destiny laboratory of the International Space Station. ISSAC, a successor of the earlier AgCam, will operate in conjunction with EarthKAM, both instruments to conduct simultaneous but independent operations in the WORF rack in Destiny.

  15. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Conducting the comparison study. 761...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the comparison study samples using the alternative method. For an alternative extraction method or alternative...

  16. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Conducting the comparison study. 761...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the comparison study samples using the alternative method. For an alternative extraction method or alternative...

  17. High temperature conductivity of potassium-beta(double prime)-alumina

    NASA Technical Reports Server (NTRS)

    Williams, R. M.; Jeffries-Nakamura, B.; Underwood, M. L.; Ryan, M. A.; O'Connor, D.; Kikkert, S.

    1992-01-01

    Potassium beta(double prime)-alumina (BDPA) single crystals have been reported by several groups to leave higher ionic conductivity than sodium BDPA crystals at room temperature, and similar conductivities are obtained at temperatures up to 600-700 K. Potassium BDPA ceramics have been reported to have significantly poorer conductivities than those of sodium BDPA ceramics, but conductivity measurements at temperatures above 625 K have not been reported. In this study, K(+)-BDPA ceramics were prepared from Na(+)-BDPA ceramic using a modified version of the exchange reaction with KCl vapor reported by Crosbie and Tennenhouse (1982), and the conductivity has been measured in K vapor at temperatures up to 1223 K, using the method of Cole et al. (1979). The results indicate reasonable agreement with earlier data on K(+)-BDPA ceramic measured in a liquid K cell, but show that the K(+)-BDPA ceramic's conductivity approaches that of Na(+)-BDPA ceramic at higher temperatures, being within a factor of four at 700 K and 60 percent of the conductivity of Na(+)-BDPA at T over 1000 K. Both four-probe dc conductivity and four probe ac impedance measurements were used to characterize the conductivity. A rather abrupt change in the grain boundary resistance suggesting a possible phase change in the intergranular material, potassium aluminate, is seen in the ac impedance behavior.

  18. Clinical presentation of retinoblastoma in Alexandria: A step toward earlier diagnosis.

    PubMed

    Soliman, Sameh E; Eldomiaty, Wesam; Goweida, Mohamed B; Dowidar, Amgad

    2017-01-01

    To evaluate the clinical presentation of retinoblastoma in Alexandria, Egypt, correlate the timing of accurate diagnosis with the presence of advanced disease and identify causes of delayed presentation. Retrospective noncomparative single institution study reviews demographic and clinical data of all new children with retinoblastoma presenting to Alexandria Main University ocular oncology clinic (OOC) from January 2012 to June 2014. Diagnosis time was from initial parental complaint to retinoblastoma diagnosis and referral time was from retinoblastoma diagnosis to presentation to the Alexandria OCC. Delayed Diagnosis and referral were counted if >2 weeks. Advanced presentation is defined as clinical TNMH (8th edition) staging of cT2 or cT3 (international intraocular retinoblastoma classification group D or E) in at least one eye or the presence of extra-ocular disease (cT4). Seventy eyes of 47 children were eligible: 52% unilateral, 7% with family history and 96% presented with leukocorea. Sixty-four percent of children had advanced intraocular disease and none had extra-ocular disease. Delayed presentation occurred in 58% of children and was significantly associated with advanced disease in both unilaterally and bilaterally affected children (p = 0.003, 0.002 respectively). The delay in diagnosis was more in unilateral cases while the delay in referral was more in bilateral cases. The main cause of delayed presentation in unilateral retinoblastoma was misdiagnosis (30%) while parental shopping for second medical opinion (30%) was the main cause in bilateral children. Delayed diagnosis is a problem affecting retinoblastoma management. Better medical education and training, health education and earlier screening are recommended to achieve earlier diagnosis.

  19. Very Early Predictors of Conduct Problems and Crime: Results from a National Cohort Study

    ERIC Educational Resources Information Center

    Murray, Joseph; Irving, Barrie; Farrington, David P.; Colman, Ian; Bloxsom, Claire A. J.

    2010-01-01

    Background: Longitudinal research has produced a wealth of knowledge about individual, family, and social predictors of crime. However, nearly all studies have started after children are age 5, and little is known about earlier risk factors. Methods: The 1970 British Cohort Study is a prospective population survey of more than 16,000 children born…

  20. Factors associated with late diagnosis of HIV infection and missed opportunities for earlier testing.

    PubMed

    Gullón, Alejandra; Verdejo, José; de Miguel, Rosa; Gómez, Ana; Sanz, Jesús

    2016-10-01

    Late diagnosis (LD) of human immunodeficiency virus (HIV) infection continues to be a significant problem that increases disease burden both for patients and for the public health system. Guidelines have been updated in order to facilitate earlier HIV diagnosis, introducing "indicator condition-guided HIV testing". In this study, we analysed the frequency of LD and associated risk factors. We retrospectively identified those cases that could be considered missed opportunities for an earlier diagnosis. All patients newly diagnosed with HIV infection who attended Hospital La Princesa, Madrid (Spain) between 2007 and 2014 were analysed. We collected epidemiological, clinical and immunological data. We also reviewed electronic medical records from the year before the HIV diagnosis to search for medical consultations due to clinical indicators. HIV infection was diagnosed in 354 patients. The median CD4 count at presentation was 352 cells/mm(3). Overall, 158 patients (50%) met the definition of LD, and 97 (30.7%) the diagnosis of advanced disease. LD was associated with older age and was more frequent amongst immigrants. Heterosexual relations and injection drug use were more likely to be the reasons for LD than relations between men who have sex with men. During the year preceding the diagnosis, 46.6% of the patients had sought medical advice owing to the presence of clinical indicators that should have led to HIV testing. Of those, 24 cases (14.5%) were classified as missed opportunities for earlier HIV diagnosis because testing was not performed. According to these results, all health workers should pursue early HIV diagnosis through the proper implementation of HIV testing guidelines. Such an approach would prove directly beneficial to the patient and indirectly beneficial to the general population through the reduction in the risk of transmission.

  1. Inevitable end-of-21st-century trends toward earlier surface runoff timing in California's Sierra Nevada Mountains

    NASA Astrophysics Data System (ADS)

    Schwartz, M. A.; Hall, A. D.; Sun, F.; Walton, D.; Berg, N.

    2015-12-01

    Hybrid dynamical-statistical downscaling is used to produce surface runoff timing projections for California's Sierra Nevada, a high-elevation mountain range with significant seasonal snow cover. First, future climate change projections (RCP8.5 forcing scenario, 2081-2100 period) from five CMIP5 global climate models (GCMs) are dynamically downscaled. These projections reveal that future warming leads to a shift toward earlier snowmelt and surface runoff timing throughout the Sierra Nevada region. Relationships between warming and surface runoff timing from the dynamical simulations are used to build a simple statistical model that mimics the dynamical model's projected surface runoff timing changes given GCM input or other statistically-downscaled input. This statistical model can be used to produce surface runoff timing projections for other GCMs, periods, and forcing scenarios to quantify ensemble-mean changes, uncertainty due to intermodel variability and consequences stemming from choice of forcing scenario. For all CMIP5 GCMs and forcing scenarios, significant trends toward earlier surface runoff timing occur at elevations below 2500m. Thus, we conclude that trends toward earlier surface runoff timing by the end-of-the-21st century are inevitable. The changes to surface runoff timing diagnosed in this study have implications for many dimensions of climate change, including impacts on surface hydrology, water resources, and ecosystems.

  2. Do BRCA1/2 mutation carriers have an earlier onset of natural menopause?

    PubMed

    van Tilborg, Theodora C; Broekmans, Frank J; Pijpe, Anouk; Schrijver, Lieske H; Mooij, Thea M; Oosterwijk, Jan C; Verhoef, Senno; Gómez Garcia, Encarna B; van Zelst-Stams, Wendy A; Adank, Muriel A; van Asperen, Christi J; van Doorn, Helena C; van Os, Theo A; Bos, Anna M; Rookus, Matti A; Ausems, Margreet G

    2016-08-01

    It has been hypothesized that BRCA1/2 mutation carriers have an earlier age at natural menopause (ANM), although to date findings are inconclusive. This study assessed the influence of BRCA mutation status on ANM, and aimed to explore the reasons of inconsistency in the literature. Cross-sectional assessment from an ongoing nationwide cohort study among members of BRCA1/2 mutated families. Information was obtained by a standardized questionnaire. Kaplan-Meier curves were constructed, and Cox regression was used to assess the association between BRCA1/2 mutation status and ANM. Adjustments were made for birth cohort, family, smoking, use of hormonal contraceptives, and parity. A total of 1,208 BRCA1/2 mutation carriers and 2,211 proven noncarriers were included. Overall, no association was found between BRCA1/2 mutation status and ANM (adjusted hazard ratio [HR] = 1.06 [95% CI, 0.87-1.30]). We examined if the null finding was due to informative censoring by uptake of risk-reducing salpingo-oophorectomy. Indeed, within the oldest birth cohort, in which the percentage of surgical menopause events was lowest and comparable between carriers and noncarriers, the HR for earlier natural menopause in carriers was 1.45 (95% CI, 1.09-1.94). The second oldest birth cohort, however, demonstrated a decreased HR (0.67 [95% CI, 0.46-0.98]), and thus no trend over birth cohorts was found. Various types of selection bias hamper the comparison of ANM between BRCA1/2 mutation carriers and noncarriers, genetically tested in the clinic.

  3. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Conducting the comparison study. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the...

  4. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Conducting the comparison study. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the...

  5. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Conducting the comparison study. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the...

  6. Changing facial phenotype in Cohen syndrome: towards clues for an earlier diagnosis.

    PubMed

    El Chehadeh-Djebbar, Salima; Blair, Edward; Holder-Espinasse, Muriel; Moncla, Anne; Frances, Anne-Marie; Rio, Marlène; Debray, François-Guillaume; Rump, Patrick; Masurel-Paulet, Alice; Gigot, Nadège; Callier, Patrick; Duplomb, Laurence; Aral, Bernard; Huet, Frédéric; Thauvin-Robinet, Christel; Faivre, Laurence

    2013-07-01

    Cohen syndrome (CS) is a rare autosomal recessive condition caused by mutations and/or large rearrangements in the VPS13B gene. CS clinical features, including developmental delay, the typical facial gestalt, chorioretinal dystrophy (CRD) and neutropenia, are well described. CS diagnosis is generally raised after school age, when visual disturbances lead to CRD diagnosis and to VPS13B gene testing. This relatively late diagnosis precludes accurate genetic counselling. The aim of this study was to analyse the evolution of CS facial features in the early period of life, particularly before school age (6 years), to find clues for an earlier diagnosis. Photographs of 17 patients with molecularly confirmed CS were analysed, from birth to preschool age. By comparing their facial phenotype when growing, we show that there are no special facial characteristics before 1 year. However, between 2 and 6 years, CS children already share common facial features such as a short neck, a square face with micrognathia and full cheeks, a hypotonic facial appearance, epicanthic folds, long ears with an everted upper part of the auricle and/or a prominent lobe, a relatively short philtrum, a small and open mouth with downturned corners, a thick lower lip and abnormal eye shapes. These early transient facial features evolve to typical CS facial features with aging. These observations emphasize the importance of ophthalmological tests and neutrophil count in children in preschool age presenting with developmental delay, hypotonia and the facial features we described here, for an earlier CS diagnosis.

  7. Delusions and underlying needs in older adults with Alzheimer's disease: influence of earlier life experiences and the current environment.

    PubMed

    Wang, Jing-Jy; Cheng, Wen-Yun; Lai, Pei-Ru; Pai, Ming-Chyi

    2014-12-01

    Delusions are one of the most severe psychiatric symptoms of individuals with Alzheimer's disease (AD), which often increase the stress experienced by caregivers. The purpose of this study was to understand the influences of earlier life experiences and the current environment on delusions, as well as the underlying needs of older adults with AD who experience delusions. Using an exploratory research design with a qualitative approach and purposive sampling, 20 family caregivers were interviewed. Two psychosocial types of attributes of delusion were categorized: Type A, the influence of earlier life experiences; and Type B, current environmental influences. The underlying needs of those with delusions include physical comfort, a desire to be secure, and a sense of belonging. The contents of delusions are easily influenced by patients' earlier negative experiences and responsibilities, whereas the current environment exerts a crucial influence on the occurrence, frequency, and severity of specific delusions. These results can facilitate planning for patient-centered care by enhancing health care providers' understanding of the psychosocial and environmental attributes and needs behind delusions. Copyright 2014, SLACK Incorporated.

  8. Bioconversion study conducted by JPL

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J.

    1978-01-01

    The Jet Propulsion Laboratory (JPL) of Caltech conducted a study of bioconversion as a means of identifying the role of biomass for meeting the national energy fuel and chemical requirements and the role and means for JPL-Caltech involvement in bioconversion. The bioconversion study included the following categories; biomass sources, chemicals from biomass, thermochemical conversion of biomass to fuels, biological conversion of biomass to fuels and chemicals, and basic bioconversion sciences. A detailed review is included of the bioconversion fields cited with specific conclusions and recommendations given for future research and development and overall biomass system engineering and economic studies.

  9. Psychological health in siblings who lost a brother or sister to cancer 2 to 9 years earlier.

    PubMed

    Eilegård, Alexandra; Steineck, Gunnar; Nyberg, Tommy; Kreicbergs, Ulrika

    2013-03-01

    The objective of this study was to assess long-term psychological distress in siblings who lost a brother or sister to cancer 2 to 9 years earlier, as compared with a control group of non-bereaved siblings from the general population. During 2009, we conducted a nationwide follow-up study in Sweden by using an anonymous study-specific questionnaire. Siblings who had lost a brother or sister to cancer between the years 2000 and 2007 and also a control group of non-bereaved siblings from the general population were invited to participate. The Hospital Anxiety and Depression Scale (HADS) was used to measure psychological distress, and to test for differences in the ordinal outcome responses between the groups, we used Wilcoxon-Mann-Whitney rank-sum test. Among the bereaved siblings, 174/240 (73%) participated and 219/293 (75%) among the non-bereaved. Self-assessed low self-esteem (p = 0.002), difficulties falling asleep (p = 0.005), and low level of personal maturity (p = 0.007) at follow-up were more prevalent among bereaved siblings. However, anxiety (p = 0.298) and depression (p = 0.946), according to HADS, were similar. Bereaved siblings are at increased risk of low self-esteem, low level of personal maturity and difficulties falling asleep as compared with non-bereaved peers. Yet, the bereaved were not more likely to report anxiety or depression. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Peer Deviancy Training and Peer Coercion: Dual Processes Associated with Early-Onset Conduct Problems

    ERIC Educational Resources Information Center

    Snyder, James; Schrepferman, Lynn; McEachern, Amber; Barner, Stacy; Johnson, Kassy; Provines, Jessica

    2008-01-01

    The prospective relationships of conduct problems and peer coercion and deviancy training during kindergarten (mean age = 5.3 years) to overt and covert conduct problems in third-fourth grade were examined in a sample of 267 boys and girls. Coercion and deviancy training were distinct peer processes. Both were associated with earlier child conduct…

  11. Number of Diverticulitis Episodes Before Resection and Factors Associated With Earlier Interventions

    PubMed Central

    Simianu, Vlad V.; Fichera, Alessandro; Bastawrous, Amir L.; Davidson, Giana H.; Florence, Michael G.; Thirlby, Richard C.; Flum, David R.

    2016-01-01

    IMPORTANCE Despite professional recommendations to delay elective colon resection for patients with uncomplicated diverticulitis, early surgery (after <3 preceding episodes) appears to be common. Several factors have been suggested to contribute to early surgery, including increasing numbers of younger patients, a lower threshold to operate laparoscopically, and growing recognition of “smoldering” (or nonrecovering) diverticulitis episodes. However, the relevance of these factors in early surgery has not been well tested, and most prior studies have focused on hospitalizations, missing outpatient events and making it difficult to assess guideline adherence in earlier interventions. OBJECTIVE To describe patterns of episodes of diverticulitis before surgery and factors associated with earlier interventions using inpatient, outpatient, and antibiotic prescription claims. DESIGN, SETTING, AND PARTICIPANTS This investigation was a nationwide retrospective cohort study from January 1, 2009, to December 31, 2012. The dates of the analysis were July 2014 to May 2015. Participants were immunocompetent adult patients (age range, 18-64 years) with incident, uncomplicated diverticulitis. EXPOSURE Elective colectomy for diverticulitis. MAIN OUTCOMES AND MEASURES Inpatient, outpatient, and antibiotic prescription claims for diverticulitis captured in the MarketScan (Truven Health Analytics) databases. RESULTS Of 87 461 immunocompetent patients having at least 1 claim for diverticulitis, 6.4% (n = 5604) underwent a resection. The final study cohort comprised 3054 nonimmunocompromised patients who underwent elective resection for uncomplicated diverticulitis, of whom 55.6% (n = 1699) were male. Before elective surgery, they had a mean (SD) of 1.0 (0.9) inpatient claims, 1.5 (1.5) outpatient claims, and 0.5 (1.2) antibiotic prescription claims related to diverticulitis. Resection occurred after fewer than 3 episodes in 94.9% (2897 of 3054) of patients if counting inpatient

  12. A primary care Web-based Intervention Modeling Experiment replicated behavior changes seen in earlier paper-based experiment.

    PubMed

    Treweek, Shaun; Francis, Jill J; Bonetti, Debbie; Barnett, Karen; Eccles, Martin P; Hudson, Jemma; Jones, Claire; Pitts, Nigel B; Ricketts, Ian W; Sullivan, Frank; Weal, Mark; MacLennan, Graeme

    2016-12-01

    Intervention Modeling Experiments (IMEs) are a way of developing and testing behavior change interventions before a trial. We aimed to test this methodology in a Web-based IME that replicated the trial component of an earlier, paper-based IME. Three-arm, Web-based randomized evaluation of two interventions (persuasive communication and action plan) and a "no intervention" comparator. The interventions were designed to reduce the number of antibiotic prescriptions in the management of uncomplicated upper respiratory tract infection. General practitioners (GPs) were invited to complete an online questionnaire and eight clinical scenarios where an antibiotic might be considered. One hundred twenty-nine GPs completed the questionnaire. GPs receiving the persuasive communication did not prescribe an antibiotic in 0.70 more scenarios (95% confidence interval [CI] = 0.17-1.24) than those in the control arm. For the action plan, GPs did not prescribe an antibiotic in 0.63 (95% CI = 0.11-1.15) more scenarios than those in the control arm. Unlike the earlier IME, behavioral intention was unaffected by the interventions; this may be due to a smaller sample size than intended. A Web-based IME largely replicated the findings of an earlier paper-based study, providing some grounds for confidence in the IME methodology. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Diagnosis of varicoceles in men undergoing vasectomy may lead to earlier detection of hypogonadism.

    PubMed

    Liu, Joceline S; Jones, Madeline; Casey, Jessica T; Fuchs, Amanda B; Cashy, John; Lin, William W

    2014-06-01

    To determine the temporal relationship between vasectomy, varicocele, and hypogonadism diagnosis. Many young men undergo their first thorough genitourinary examination in their adult lives at the time of vasectomy consultation, providing a unique opportunity for diagnosis of asymptomatic varicoceles. Varicoceles have recently been implicated as a possible reversible contributor to hypogonadism. Hypogonadism may be associated with significant adverse effect, including decreased libido, impaired cognitive function, and increased cardiovascular events. Early diagnosis and treatment of hypogonadism may prevent these adverse sequelae. Data were collected from the Truven Health Analytics MarketScan database, a large outpatient claims database. We reviewed records between 2003 and 2010 for male patients between the ages of 25 and 50 years with International Classification of Diseases, Ninth Revision codes for hypogonadism, vasectomy, and varicocele, and queried dates of first claim. A total of 15,679 men undergoing vasectomies were matched with 156,790 men with nonvasectomy claims in the same year. Vasectomy patients were diagnosed with varicocele at an earlier age (40.9 vs 42.5 years; P=.009). We identified 224,817 men between the ages of 25 and 50 years with a claim of hypogonadism, of which 5883 (2.6%) also had a claim of varicocele. Men with hypogonadism alone were older at presentation compared with men with an accompanying varicocele (41.3 [standard deviation±6.5] vs 34.9 [standard deviation±6.1]; P<.001). Men undergoing vasectomies are diagnosed with varicoceles at a younger age than age-matched controls. Men with varicoceles present with hypogonadism earlier than men without varicoceles. Earlier diagnosis of varicocele at the time of vasectomy allows for earlier detection of hypogonadism. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Selection of children to provide care: the effect of earlier parental transfers.

    PubMed

    Henretta, J C; Hill, M S; Li, W; Soldo, B J; Wolf, D A

    1997-05-01

    We use the first wave of data from the Asset and Health Dynamics Among the Oldest Old (AHEAD) study to examine the effects of past parent-to-child financial transfers on selection of a child to provide assistance with basic personal care for unmarried parents. We estimate a fixed-effects conditional logit model and find a positive and significant association between past financial transfers and a child's current helping behavior. The coefficient of past financial transfers is in the direction hypothesized, and its magnitude is 80% as large as that of gender, a well-documented powerful predictor of parental caregiving. There appears to be substantial evidence that earlier parent-to-child financial gifts play a role in determining which child in the family will provide assistance.

  15. Earlier reperfusion in patients with ST-elevation Myocardial infarction by use of helicopter

    PubMed Central

    2012-01-01

    Background In patients with ST-elevation myocardial infarction (STEMI) reperfusion therapy should be initiated as soon as possible. This study evaluated whether use of a helicopter for transportation of patients is associated with earlier initiation of reperfusion therapy. Material and methods A prospective study was conducted, including patients with STEMI and symptom duration less than 12 hours, who had primary percutaneous coronary intervention (PPCI) performed at Aarhus University Hospital in Skejby. Patients with a health care system delay (time from emergency call to first coronary intervention) of more than 360 minutes were excluded. The study period ran from 1.1.2011 until 31.12.2011. A Western Denmark Helicopter Emergency Medical Service (HEMS) project was initiated 1.6.2011 for transportation of patients with time-critical illnesses, including STEMI. Results The study population comprised 398 patients, of whom 376 were transported by ambulance Emergency Medical Service (EMS) and 22 by HEMS. Field-triage directly to the PCI-center was used in 338 of patients. The median system delay was 94 minutes among those field-triaged, and 168 minutes among those initially admitted to a local hospital. Patients transported by EMS and field-triaged were stratified into four groups according to transport distance from the scene of event to the PCI-center: ≤25 km., 26–50 km., 51–75 km. and > 75 km. For these groups, the median system delay was 78, 89, 99, and 141 minutes. Among patients transported by HEMS and field-triaged the estimated median transport distance by ground transportation was 115 km, and the observed system delay was 107 minutes. Based on second order polynomial regression, it was estimated that patients with a transport distance of >60 km to the PCI-center may benefit from helicopter transportation, and that transportation by helicopter is associated with a system delay of less than 120 minutes even at a transport distance up to 150 km

  16. Earlier reperfusion in patients with ST-elevation myocardial infarction by use of helicopter.

    PubMed

    Knudsen, Lars; Stengaard, Carsten; Hansen, Troels Martin; Lassen, Jens Flensted; Terkelsen, Christian Juhl

    2012-10-04

    In patients with ST-elevation myocardial infarction (STEMI) reperfusion therapy should be initiated as soon as possible. This study evaluated whether use of a helicopter for transportation of patients is associated with earlier initiation of reperfusion therapy. A prospective study was conducted, including patients with STEMI and symptom duration less than 12 hours, who had primary percutaneous coronary intervention (PPCI) performed at Aarhus University Hospital in Skejby. Patients with a health care system delay (time from emergency call to first coronary intervention) of more than 360 minutes were excluded. The study period ran from 1.1.2011 until 31.12.2011. A Western Denmark Helicopter Emergency Medical Service (HEMS) project was initiated 1.6.2011 for transportation of patients with time-critical illnesses, including STEMI. The study population comprised 398 patients, of whom 376 were transported by ambulance Emergency Medical Service (EMS) and 22 by HEMS. Field-triage directly to the PCI-center was used in 338 of patients. The median system delay was 94 minutes among those field-triaged, and 168 minutes among those initially admitted to a local hospital. Patients transported by EMS and field-triaged were stratified into four groups according to transport distance from the scene of event to the PCI-center: ≤25 km., 26-50 km., 51-75 km. and > 75 km. For these groups, the median system delay was 78, 89, 99, and 141 minutes. Among patients transported by HEMS and field-triaged the estimated median transport distance by ground transportation was 115 km, and the observed system delay was 107 minutes. Based on second order polynomial regression, it was estimated that patients with a transport distance of >60 km to the PCI-center may benefit from helicopter transportation, and that transportation by helicopter is associated with a system delay of less than 120 minutes even at a transport distance up to 150 km. The present study indicates that use of a

  17. Conductivity and transport studies of plasticized chitosan-based proton conducting biopolymer electrolytes

    NASA Astrophysics Data System (ADS)

    Shukur, M. F.; Yusof, Y. M.; Zawawi, S. M. M.; Illias, H. A.; Kadir, M. F. Z.

    2013-11-01

    This paper focuses on the conductivity and transport properties of chitosan-based solid biopolymer electrolytes containing ammonium thiocyanate (NH4SCN). The sample containing 40 wt% NH4SCN exhibited the highest conductivity value of (1.81 ± 0.50) × 10-4 S cm-1 at room temperature. Conductivity has increased to (1.51 ± 0.12) × 10-3 S cm-1 with the addition of 25 wt% glycerol. The temperature dependence of conductivity for both salted and plasticized systems obeyed the Arrhenius rule. The activation energy (Ea) was calculated for both systems and it is found that the sample with 40 wt% NH4SCN in the salted system obtained an Ea value of 0.148 eV and that for the sample containing 25 wt% glycerol in the plasticized system is 0.139 eV. From the Fourier transform infrared studies, carboxamide and amine bands shifted to lower wavenumbers, indicating that chitosan has interacted with NH4SCN salt. Changes in the C-O stretching vibration band intensity are observed at 1067 cm-1 with the addition of glycerol. The Rice and Roth model was used to explain the transport properties of the salted and plasticized systems.

  18. The ADVANCE Code of Conduct for collaborative vaccine studies.

    PubMed

    Kurz, Xavier; Bauchau, Vincent; Mahy, Patrick; Glismann, Steffen; van der Aa, Lieke Maria; Simondon, François

    2017-04-04

    Lessons learnt from the 2009 (H1N1) flu pandemic highlighted factors limiting the capacity to collect European data on vaccine exposure, safety and effectiveness, including lack of rapid access to available data sources or expertise, difficulties to establish efficient interactions between multiple parties, lack of confidence between private and public sectors, concerns about possible or actual conflicts of interest (or perceptions thereof) and inadequate funding mechanisms. The Innovative Medicines Initiative's Accelerated Development of VAccine benefit-risk Collaboration in Europe (ADVANCE) consortium was established to create an efficient and sustainable infrastructure for rapid and integrated monitoring of post-approval benefit-risk of vaccines, including a code of conduct and governance principles for collaborative studies. The development of the code of conduct was guided by three core and common values (best science, strengthening public health, transparency) and a review of existing guidance and relevant published articles. The ADVANCE Code of Conduct includes 45 recommendations in 10 topics (Scientific integrity, Scientific independence, Transparency, Conflicts of interest, Study protocol, Study report, Publication, Subject privacy, Sharing of study data, Research contract). Each topic includes a definition, a set of recommendations and a list of additional reading. The concept of the study team is introduced as a key component of the ADVANCE Code of Conduct with a core set of roles and responsibilities. It is hoped that adoption of the ADVANCE Code of Conduct by all partners involved in a study will facilitate and speed-up its initiation, design, conduct and reporting. Adoption of the ADVANCE Code of Conduct should be stated in the study protocol, study report and publications and journal editors are encouraged to use it as an indication that good principles of public health, science and transparency were followed throughout the study. Copyright © 2017

  19. Pressure and temperature dependences of the ionic conductivities of the thallous halidesTlCl, TlBr, and TlI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Samara, G.A.

    1981-01-15

    Detailed studies of the pressure and temperature dependences of the ionic conductivities of TlCl and TlBr have allowed determination of the lattice volume relaxations and energies associated with the formation and motion of Schottky defects in these crystals. The volume relaxations deduced from the conductivity are found to be comparable in magnitude with values calculated from the strain energy model and a dynamical model. The association energy of Tl/sup +/ vacancies and divalent impurities was also determined for TlBr. A particularly important result is the finding that for these CsCl-type crystals the relaxation of the lattice associated with vacancy formationmore » is outward. Earlier studies on ionic crystals having the NaCl structure have yielded a similar result. This outward relaxation thus appears to be a general result for ionic crystals of both the NaCl and CsCl types (and possibly other ionic lattice types), in disagreement with earlier theoretical calculations which show that the relaxation should be inward for all models of ionic vacancies investigated. The conductivity of TlI was studied in both the (low temperature and pressure) orthorhombic phase as well as in the cubic CsCl-type phase. There is a large electronic contribution to the conductivity in the orthorhombic phase. An interesting result for all three materials is the observation in the cubic phase of a pressure-induced transition from ionic to electronic conduction. This is in qualitative agreement with what is known about the pressure dependences of the electronic structure of these materials.« less

  20. Ion Conductivity and Sensors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bychkov, E.; Tveryanovich, Y.; Vlasov, Y.

    2005-03-02

    Ionic transport in glasses was discovered in the 19th century following the classical work of Warburg (1884). Since then, considerable progress has been achieved in both theoretical understanding and practical applications of ion-conducting vitreous systems (see Frischat, 1975; Malugani and Robert, 1980; Ribes, Barrau and Souquet, 1980; Kennedy and Yang, 1987; Vlasov and Bychkov, 1987; Hayashi, Tatsumisago and Minami, 1999; Doremus, 1962 and references therein). Nevertheless, this topic and especially the ion-conducting mechanisms in disordered solids need additional study using traditional macroscopic methods (ac and dc electrical conductivity, tracer diffusion, and ion transport number measurements), as well as advanced structuralmore » techniques on third generation synchrotron light sources and spallation neutron sources over a large range of the scattering vector Q. This approach led to the discovery of important features: in particular, different transport regimes at low and high mobile ion content that are closely related to a competition between the stochastic scenario and a non-random distribution of the mobile ions in the glass network. Well-known experimental findings such as compositional dependence of the Haven ratio H{sub R}, interpreted earlier by a number of drastically different ion transport models, can also be explained using a unified approach. Many of the new experimental results were obtained for silver and copper chalcogenide glasses which appear to be useful model materials, in part because of a large accessible composition domain, as well as coverage of five orders of magnitude in the mobile cation content, and corresponding dramatic changes in the ionic transport up to 10 orders of magnitude.« less

  1. Earlier Right Ventricular Pacing in Cardiac Resynchronization Therapy for a Patient with Right Axis Deviation.

    PubMed

    Hattori, Yusuke; Ishibashi, Kohei; Noda, Takashi; Okamura, Hideo; Kanzaki, Hideaki; Anzai, Toshihisa; Yasuda, Satoshi; Kusano, Kengo

    2017-09-01

    We describe the case of a 37-year-old woman who presented with complete right bundle branch block and right axis deviation. She was admitted to our hospital due to severe heart failure and was dependent on inotropic agents. Cardiac resynchronization therapy was initiated but did not improve her condition. After the optimization of the pacing timing, we performed earlier right ventricular pacing, which led to an improvement of her heart failure. Earlier right ventricular pacing should be considered in patients with complete right bundle branch block and right axis deviation when cardiac resynchronization therapy is not effective.

  2. Adiposity, Dysmetabolic Traits, and Earlier Onset of Female Puberty in Adolescent Offspring of Women With Gestational Diabetes Mellitus: A Clinical Study Within the Danish National Birth Cohort.

    PubMed

    Grunnet, Louise G; Hansen, Susanne; Hjort, Line; Madsen, Camilla M; Kampmann, Freja B; Thuesen, Anne Cathrine B; Granstrømi, Charlotta; Strøm, Marin; Maslova, Ekaterina; Frikke-Schmidt, Ruth; Damm, Peter; Chavarro, Jorge E; Hu, Frank B; Olsen, Sjurdur F; Vaag, Allan

    2017-12-01

    Offspring of pregnancies affected by gestational diabetes mellitus (GDM) are at increased risk of the development of type 2 diabetes. However, the extent to which these dysmetabolic traits may be due to offspring and/or maternal adiposity is unknown. We examined body composition and associated cardiometabolic traits in 561 9- to 16-year-old offspring of mothers with GDM and 597 control offspring. We measured anthropometric characteristics; puberty status; blood pressure; and fasting glucose, insulin, C-peptide, and lipid levels; and conducted a DEXA scan in a subset of the cohort. Differences in the outcomes between offspring of mothers with GDM and control subjects were examined using linear and logistic regression models. After adjustment for age and sex, offspring of mothers with GDM displayed higher weight, BMI, waist-to-hip ratio (WHR), systolic blood pressure, and resting heart rate and lower height. Offspring of mothers with GDM had higher total and abdominal fat percentages and lower muscle mass percentages, but these differences disappeared after correction for offspring BMI. The offspring of mothers with GDM displayed higher fasting plasma glucose, insulin, C-peptide, HOMA-insulin resistance (IR), and plasma triglyceride levels, whereas fasting plasma HDL cholesterol levels were decreased. Female offspring of mothers with GDM had an earlier onset of puberty than control offspring. Offspring of mothers with GDM had significantly higher BMI, WHR, fasting glucose, and HOMA-IR levels after adjustment for maternal prepregnancy BMI, and glucose and HOMA-IR remained elevated in the offspring of mothers with GDM after correction for both maternal and offspring BMIs. In summary, adolescent offspring of women with GDM show increased adiposity, an adverse cardiometabolic profile, and earlier onset of puberty among girls. Increased fasting glucose and HOMA-IR levels among the offspring of mothers with GDM may be explained by the programming effects of hyperglycemia

  3. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the removal process, remedial investigation/ feasibility study (RI/FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response...

  4. Performance standards of the nerve conduction study technologist.

    PubMed

    Neal, Peggy J; Katirji, Bashar

    2008-06-01

    The primary performance standard of the nerve conduction study technologist is to perform nerve conduction studies (NCS) on patients with trauma or diseases of the peripheral nervous system. However, to be in compliance with various healthcare/medical accreditation agencies, such as Occupational Safety and Health Administration (OSHA), Centers for Disease Control and Prevention (CDC), or The Joint Commission [formerly known as the Joint Commission on Accreditation of Healthcare Organizations (JCAHO)], there are many other important performance objectives that must be met as well. It is the responsibility of the NCS technologist to meet these standards on a daily basis. Once these standards become an expected responsibility of the NCS technologist's position, the patient undergoing a nerve conduction study should be assured of a high quality test performed in an optimal safety environment.

  5. Challenges in conducting psychiatry studies in India

    PubMed Central

    Kharawala, Saifuddin; Dalal, Jeroze

    2011-01-01

    A large number of psychiatry studies are conducted in India. Psychiatry studies are complex and present unique challenges in the Indian setting. Ethical issues pertaining to the risk of worsening of illness, use of placebo and validity of informed consents are commonly faced. Site selection can be difficult due to the relative paucity of ICH-GCP (International Conference on Harmonisation - Good Clinical Practice) trained psychiatry investigators in India. Recruitment can be challenging due to issues such as strict eligibility criteria, (lack of) availability of caregiver, illness-related considerations, etc. Assessment of the consent capacity of patients is not simple, while structured assessments are not commonly employed. As the illness fluctuates, the consent capacity may change, thus requiring continued assessment of consent capacity. Study patients run the risk of worsening of illness and suicide due to exposure to inactive treatments; this risk is counterbalanced by use of appropriate study designs, as well as the indirect psychotherapeutic support received. Psychiatry studies are associated with a high placebo response. This necessitates conduct of placebo-controlled studies despite the attendant difficulties. Also, the high placebo response is often the cause of failed trials. Rating scales are essential for assessment of drug response. Some rating instruments as well as some rater training procedures may not be suitable for the Indian setting. Technological advancements may increase the procedural complexity but improve the quality of ratings. Psychiatry studies present monitors and auditors with unique scenarios too. Utilization of psychiatry specific training and expertise is recommended to ensure successful conduct of these studies in India. PMID:21584176

  6. Nerve conduction studies are safe in patients with central venous catheters.

    PubMed

    London, Zachary N; Mundwiler, Andrew; Oral, Hakan; Gallagher, Gary W

    2017-08-01

    It is unknown if central venous catheters bypass the skin's electrical resistance and engender a risk of nerve conduction study-induced cardiac arrhythmia. The objective of this study is to determine if nerve conduction studies affect cardiac conduction and rhythm in patients with central venous catheters. Under continuous 12-lead electrocardiogram monitoring, subjects with and without central venous catheters underwent a series of upper extremity nerve conduction studies. A cardiologist reviewed the electrocardiogram tracings for evidence of cardiac conduction abnormality or arrhythmia. Ten control subjects and 10 subjects with central venous catheters underwent the nerve conduction study protocol. No malignant arrhythmias or conduction abnormalities were noted in either group. Nerve conduction studies of the upper extremities, including both proximal stimulation and repetitive stimulation, do not appear to confer increased risk of cardiac conduction abnormality in those patients with central venous catheters who are not critically ill or have a prior history of arrhythmia. Muscle Nerve 56: 321-323, 2017. © 2016 Wiley Periodicals, Inc.

  7. Earlier disability of the patients followed in Multiple Sclerosis centers compared to outpatients.

    PubMed

    Debouverie, M; Laforest, L; Van Ganse, E; Guillemin, F

    2009-02-01

    The currently published works regarding the multiple sclerosis (MS) natural history report data were collected most often on population of patients recruited in MS centers. The aim was to compare the natural history of a population of patients followed in a MS centre (MSC) with patients followed outside a MS centre (NMSC). Cases were identified through the LORSEP cohort, a network of neurologists (private ambulatory practice, hospitals, and MS centers) in France. A total of 3602 patients had been analyzed: 1036 MSC patients and 2566 NMSC patients. No difference was observed regarding gender and initial symptoms. Conversely, MSC patients were younger at MS onset and were more likely to have a primary progressive initial form. Median times (years) to the EDSS scores of 3, 4, and 6 were 5.8 (5.0-6.8), 8.4 (7.9-9.0), 16.0 (14.8-18.1) in the MSC group, respectively, whereas corresponding times were 8.4 (7.9-9.0), 12.3 (11.4-13.4), 19.1 (18.0-20.2) in the NMSC group. These differences according to the type of MS supervision were statistically significant for EDSS3 (P < 0.0001), EDSS4 (P < 0.0001), and EDSS6 (P = 0.01), respectively. These findings were confirmed in Cox multivariate models. The patients followed in a MS centre had earlier disability than patients managed otherwise. Analyses exclusively conducted in patients with MS supervised in specialized centers may falsely misestimate the times needed to reach major disability landmarks. Before using registries to study the natural history of MS, efforts should be performed to verify in how far data are exhaustive and to understand the local health care system.

  8. Earlier parental set bedtimes as a protective factor against depression and suicidal ideation.

    PubMed

    Gangwisch, James E; Babiss, Lindsay A; Malaspina, Dolores; Turner, J Blake; Zammit, Gary K; Posner, Kelly

    2010-01-01

    To examine the relationships between parental set bedtimes, sleep duration, and depression as a quasi-experiment to explore the potentially bidirectional relationship between short sleep duration and depression. Short sleep duration has been shown to precede depression, but this could be explained as a prodromal symptom of depression. Depression in an adolescent can affect his/her chosen bedtime, but it is less likely to affect a parent's chosen set bedtime which can establish a relatively stable upper limit that can directly affect sleep duration. Multivariate cross-sectional analyses of the ADD Health using logistic regression. United States nationally representative, school-based, probability-based sample in 1994-96. Adolescents (n = 15,659) in grades 7 to 12. Adolescents with parental set bedtimes of midnight or later were 24% more likely to suffer from depression (OR = 1.24, 95% CI 1.04-1.49) and 20% more likely to have suicidal ideation (1.20, 1.01-1.41) than adolescents with parental set bedtimes of 10:00 PM or earlier, after controlling for covariates. Consistent with sleep duration and perception of getting enough sleep acting as mediators, the inclusion of these variables in the multivariate models appreciably attenuated the associations for depression (1.07, 0.88-1.30) and suicidal ideation (1.09, 0.92-1.29). The results from this study provide new evidence to strengthen the argument that short sleep duration could play a role in the etiology of depression. Earlier parental set bedtimes could therefore be protective against adolescent depression and suicidal ideation by lengthening sleep duration.

  9. An analytical solution to the one-dimensional heat conduction-convection equation in soil

    USDA-ARS?s Scientific Manuscript database

    Heat transfer in soil occurs by conduction and convection. Infiltrating water affects soil temperature distributions, and measuring soil temperature distributions below infiltrating water can provide a signal for the flux of water. In earlier work a sine wave function (hereinafter referred to as the...

  10. Age of diagnosis of breast cancer in china: almost 10 years earlier than in the United States and the European union.

    PubMed

    Song, Qing-Kun; Li, Jing; Huang, Rong; Fan, Jin-Hu; Zheng, Rong-Shou; Zhang, Bao-Ning; Zhang, Bin; Tang, Zhong-Hua; Xie, Xiao-Ming; Yang, Hong-Jian; He, Jian-Jun; Li, Hui; Li, Jia-Yuan; Qiao, You-Lin; Chen, Wan-Qing

    2014-01-01

    The study aimed to describe the age distribution of breast cancer diagnosis among Chinese females for comparison with the United States and the European Union, and provide evidence for the screening target population in China. Median age was estimated from hospital databases from 7 tertiary hospitals in China. Population-based data in China, United States and European Union was extracted from the National Central Cancer Registry, SEER program and GLOBOCAN 2008, respectively. Age-standardized distribution of breast cancer at diagnosis in the 3 areas was estimated based on the World Standard Population 2000. The median age of breast cancer at diagnosis was around 50 in China, nearly 10 years earlier than United States and European Union. The diagnosis age in China did not vary between subgroups of calendar year, region and pathological characteristics. With adjustment for population structure, median age of breast cancer at diagnosis was 50~54 in China, but 55~59 in United States and European Union. The median diagnosis age of female breast cancer is much earlier in China than in the United States and the European Union pointing to racial differences in genetics and lifestyle. Screening programs should start at an earlier age for Chinese women and age disparities between Chinese and Western women warrant further studies.

  11. Earlier Pulmonary Valve Replacement in Down Syndrome Patients Following Tetralogy of Fallot Repair.

    PubMed

    Sullivan, Rachel T; Frommelt, Peter C; Hill, Garick D

    2017-08-01

    The association between Down syndrome and pulmonary hypertension could contribute to more severe pulmonary regurgitation after tetralogy of Fallot repair and possibly earlier pulmonary valve replacement. We compared cardiac magnetic resonance measures of pulmonary regurgitation and right ventricular dilation as well as timing of pulmonary valve replacement between those with and without Down syndrome after tetralogy of Fallot repair. Review of our surgical database from 2000 to 2015 identified patients with tetralogy of Fallot with pulmonary stenosis. Those with Down syndrome were compared to those without. The primary outcome of interest was time from repair to pulmonary valve replacement. Secondary outcomes included pulmonary regurgitation and indexed right ventricular volume on cardiac magnetic resonance imaging. The cohort of 284 patients included 35 (12%) with Down syndrome. Transannular patch repair was performed in 210 (74%). Down syndrome showed greater degree of pulmonary regurgitation (55 ± 14 vs. 37 ± 16%, p = 0.01) without a significantly greater rate of right ventricular dilation (p = 0.09). In multivariable analysis, Down syndrome (HR 2.3, 95% CI 1.2-4.5, p = 0.02) and transannular patch repair (HR 5.5, 95% CI 1.7-17.6, p = 0.004) were significant risk factors for valve replacement. Those with Down syndrome had significantly lower freedom from valve replacement (p = 0.03). Down syndrome is associated with an increased degree of pulmonary regurgitation and earlier pulmonary valve replacement after tetralogy of Fallot repair. These patients require earlier assessment by cardiac magnetic resonance imaging to determine timing of pulmonary valve replacement and evaluation for and treatment of preventable causes of pulmonary hypertension.

  12. 40 CFR 87.21 - Exhaust emission standards for Tier 4 and earlier engines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Emissions (New Aircraft Gas Turbine Engines) § 87.21 Exhaust emission standards for Tier 4 and earlier... standards. (a) Exhaust emissions of smoke from each new aircraft gas turbine engine of class T8 manufactured... from each new aircraft gas turbine engine of class TF and of rated output of 129 kilonewtons thrust or...

  13. 40 CFR 87.21 - Exhaust emission standards for Tier 4 and earlier engines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Emissions (New Aircraft Gas Turbine Engines) § 87.21 Exhaust emission standards for Tier 4 and earlier... standards. (a) Exhaust emissions of smoke from each new aircraft gas turbine engine of class T8 manufactured... from each new aircraft gas turbine engine of class TF and of rated output of 129 kilonewtons thrust or...

  14. Reducing Older Driver Motor Vehicle Collisions via Earlier Cataract Surgery

    PubMed Central

    Mennemeyer, Stephen T.; Owsley, Cynthia; McGwin, Gerald

    2013-01-01

    Older adults who undergo cataract extraction have roughly half the rate of motor vehicle collision (MVC) involvement per mile driven compared to cataract patients who do not elect cataract surgery. Currently in the U.S., most insurers do not allow payment for cataract surgery based upon the findings of a vision exam unless accompanied by an individual’s complaint of visual difficulties that seriously interfere with driving or other daily activities and individuals themselves may be slow or reluctant to complain and seek relief. As a consequence, surgery tends to occur after significant vision problems have emerged. We hypothesize that a proactive policy encouraging cataract surgery earlier for a lesser level of complaint would significantly reduce MVCs among older drivers. We used a Monte Carlo model to simulate the MVC experience of the U.S. population from age 60 to 89 under alternative protocols for the timing of cataract surgery which we call “Current Practice” (CP) and “Earlier Surgery” (ES). Our base model finds, from a societal perspective with undiscounted 2010 dollars, that switching to ES from CP reduces by about 21% the average number of MVCs, fatalities, and MVC cost per person. The net effect on total cost – all MVC costs plus cataract surgery expenditures -- is a reduction of about 16%. Quality Adjusted Life Years would increase by about 5%. From the perspective of payers for healthcare, the switch would increase cataract surgery expenditure for ages 65+ by about 8% and for ages 60 to 64 by about 47% but these expenditures are substantially offset after age 65 by reductions in the medical and emergency services component of MVC cost. Similar results occur with discounting at 3% and with various sensitivity analyses. We conclude that a policy of ES would significantly reduce MVCs and their associated consequences. PMID:23369786

  15. Electrical conductivity of MgH2 at multiple shock compression

    NASA Astrophysics Data System (ADS)

    Shakhray, Denis; Molodets, Alexander; Fortov, Vladimir

    2011-06-01

    The electrical conductivity of MgH2 has been studied under multishock compression. Earlier we had been experimentally studied metallization possibility of alane at high pressures in conditions quasiisentropic compression up to 100 GPa. A study of thermodynamic properties of MgH2 under multishock compression has been carried out also. High pressures and temperatures were obtained with an explosive device, which accelerates the metallic impactor up to 3 km/s. Identification of the hydride in experiments was made on the basis of calculations of phase trajectories loading a material in the area of existence of polymorphic phases including high-pressure phases of magnesium hydride (α and γ MgH2, hP1 and hP2). It is shown that occurrence of magnesium hydride electrical conductivity occurs in the field of existence of high-pressure hP2 phase This work was partially supported by the Presidium of the Russian Academy of Sciences within the Program of Basic Research ``Thermal Physics and Mechanics of Extreme Energy Effects and Physics of Strongly Compressed Matter and Russian Foundation for Basic Research Grant No. 10-02-01078.''

  16. Daily Use, Especially of High-Potency Cannabis, Drives the Earlier Onset of Psychosis in Cannabis Users

    PubMed Central

    Di Forti, Marta; Sallis, Hannah; Allegri, Fabio; Trotta, Antonella; Ferraro, Laura; Stilo, Simona A.; Marconi, Arianna; La Cascia, Caterina; Reis Marques, Tiago; Pariante, Carmine; Dazzan, Paola; Mondelli, Valeria; Paparelli, Alessandra; Kolliakou, Anna; Prata, Diana; Gaughran, Fiona; David, Anthony S.; Morgan, Craig; Stahl, Daniel; Khondoker, Mizanur; MacCabe, James H.; Murray, Robin M.

    2014-01-01

    Cannabis use is associated with an earlier age of onset of psychosis (AOP). However, the reasons for this remain debated. Methods: We applied a Cox proportional hazards model to 410 first-episode psychosis patients to investigate the association between gender, patterns of cannabis use, and AOP. Results: Patients with a history of cannabis use presented with their first episode of psychosis at a younger age (mean years = 28.2, SD = 8.0; median years = 27.1) than those who never used cannabis (mean years = 31.4, SD = 9.9; median years = 30.0; hazard ratio [HR] = 1.42; 95% CI: 1.16–1.74; P < .001). This association remained significant after controlling for gender (HR = 1.39; 95% CI: 1.11–1.68; P < .001). Those who had started cannabis at age 15 or younger had an earlier onset of psychosis (mean years = 27.0, SD = 6.2; median years = 26.9) than those who had started after 15 years (mean years = 29.1, SD = 8.5; median years = 27.8; HR = 1.40; 95% CI: 1.06–1.84; P = .050). Importantly, subjects who had been using high-potency cannabis (skunk-type) every day had the earliest onset (mean years = 25.2, SD = 6.3; median years = 24.6) compared to never users among all the groups tested (HR = 1.99; 95% CI: 1.50- 2.65; P < .0001); these daily users of high-potency cannabis had an onset an average of 6 years earlier than that of non-cannabis users. Conclusions: Daily use, especially of high-potency cannabis, drives the earlier onset of psychosis in cannabis users. PMID:24345517

  17. New secondary batteries utilizing electronically conductive polymer cathodes

    NASA Technical Reports Server (NTRS)

    Martin, Charles R.; White, Ralph E.

    1989-01-01

    The objectives of this project are to optimize the transport rates in electronically conductive polypyrrole films by controlling the morphology of the film and to assess the utility of these films as cathodes in a lithium/polypyrrole secondary battery. During this research period, progress has been made in improving the charge transport rate of the supermolecular-engineered polypyrrole electrode by eliminating the polypyrrole baselayer that hampered earlier work. Also, the fibril density of the polypyrrole electrode was increased, providing more electroactive sites per unit area.

  18. 42 CFR 90.7 - Decision to conduct health effects study.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Decision to conduct health effects study. 90.7... ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES ADMINISTRATIVE FUNCTIONS, PRACTICES, AND PROCEDURES § 90.7 Decision to conduct health effects study. (a) ATSDR may decide...

  19. 42 CFR 90.7 - Decision to conduct health effects study.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Decision to conduct health effects study. 90.7... ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES ADMINISTRATIVE FUNCTIONS, PRACTICES, AND PROCEDURES § 90.7 Decision to conduct health effects study. (a) ATSDR may decide...

  20. Long-term effects of earlier initiated continuous Kangaroo Mother Care (KMC) for low-birth-weight (LBW) infants in Madagascar.

    PubMed

    Nagai, Shuko; Yonemoto, Naohiro; Rabesandratana, Norotiana; Andrianarimanana, Diavolana; Nakayama, Takeo; Mori, Rintaro

    2011-12-01

    To examine the long-term effects of earlier initiated continuous Kangaroo Mother Care (KMC) for relatively stable low-birth-weight (LBW) infants in a resource-limited country. A randomized controlled trial with long-term follow-up was performed in LBW infants in Madagascar. Earlier continuous KMC (intervention group) was initiated as soon as possible within 24 h postbirth, and later continuous KMC (control group: conventional care) was initiated after complete stabilization. Outcome measures were mortality or readmission, nutritional indicators at 6-12 months postbirth and feeding condition at 6 months postbirth (ClinicalTrials.gov, NCT00531492). A total of 72 infants were followed for mortality or readmission at 6-12 months postbirth. There was no difference between the two groups (7/36 vs. 7/36, Risk ratio (RR), 1.00; 95% CIs, 0.39-2.56; p = 1.00). The proportion of exclusive breast feeding (EBF) at 6 months postbirth was significantly higher with earlier KMC than later KMC (12/29 vs. 4/26; RR 2.69; 95% CIs, 1.00-7.31; p = 0.04). There were no differences in nutritional indicators between the two groups at 6-12 months postbirth. Earlier initiated continuous KMC results in a significantly higher proportion of EBF at 6 months postbirth. Further larger-scale long-term evaluations of earlier initiated continuous KMC for LBW infants are needed. © 2011 The Author(s)/Acta Paediatrica © 2011 Foundation Acta Paediatrica.

  1. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will be...

  2. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will be...

  3. Facilitating earlier transfer of care from acute stroke services into the community.

    PubMed

    Robinson, Jennifer

    This article outlines an initiative to reduce length of stay for stroke patients within an acute hospital and to facilitate earlier transfer of care. Existing care provision was remodelled and expanded to deliver stroke care to patients within a community bed-based intermediate care facility or intermediate care at home. This new model of care has improved the delivery of rehabilitation through alternative and innovative ways of addressing service delivery that meet the needs of the patients.

  4. Size dependent polaronic conduction in hematite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sharma, Monika; Banday, Azeem; Murugavel, Sevi

    2016-05-23

    Lithium Ion Batteries have been attracted as the major renewable energy source for all portable electronic devices because of its advantages like superior energy density, high theoretical capacity, high specific energy, stable cycling and less memory effects. Recently, α-Fe{sub 2}O{sub 3} has been considered as a potential anode material due to high specific capacity, low cost, high abundance and environmental benignity. We have synthesized α-Fe{sub 2}O{sub 3} with various sizes by using the ball milling and sol-gel procedure. Here, we report the dc conductivity measurement for the crystallite size ranging from 15 nm to 50 nm. It has been observedmore » that the enhancement in the polaronic conductivity nearly two orders in magnitude while reducing the crystallite size from bulk into nano scale level. The enhancement in the conductivity is due to the augmented to compressive strain developed in the material which leads to pronounced decrease in the hopping length of polarons. Thus, nanocrystaline α-Fe{sub 2}O{sub 3} may be a better alternative anode material for lithium ion batteries than earlier reported systems.« less

  5. Daily use, especially of high-potency cannabis, drives the earlier onset of psychosis in cannabis users.

    PubMed

    Di Forti, Marta; Sallis, Hannah; Allegri, Fabio; Trotta, Antonella; Ferraro, Laura; Stilo, Simona A; Marconi, Arianna; La Cascia, Caterina; Reis Marques, Tiago; Pariante, Carmine; Dazzan, Paola; Mondelli, Valeria; Paparelli, Alessandra; Kolliakou, Anna; Prata, Diana; Gaughran, Fiona; David, Anthony S; Morgan, Craig; Stahl, Daniel; Khondoker, Mizanur; MacCabe, James H; Murray, Robin M

    2014-11-01

    Cannabis use is associated with an earlier age of onset of psychosis (AOP). However, the reasons for this remain debated. We applied a Cox proportional hazards model to 410 first-episode psychosis patients to investigate the association between gender, patterns of cannabis use, and AOP. Patients with a history of cannabis use presented with their first episode of psychosis at a younger age (mean years = 28.2, SD = 8.0; median years = 27.1) than those who never used cannabis (mean years = 31.4, SD = 9.9; median years = 30.0; hazard ratio [HR] = 1.42; 95% CI: 1.16-1.74; P < .001). This association remained significant after controlling for gender (HR = 1.39; 95% CI: 1.11-1.68; P < .001). Those who had started cannabis at age 15 or younger had an earlier onset of psychosis (mean years = 27.0, SD = 6.2; median years = 26.9) than those who had started after 15 years (mean years = 29.1, SD = 8.5; median years = 27.8; HR = 1.40; 95% CI: 1.06-1.84; P = .050). Importantly, subjects who had been using high-potency cannabis (skunk-type) every day had the earliest onset (mean years = 25.2, SD = 6.3; median years = 24.6) compared to never users among all the groups tested (HR = 1.99; 95% CI: 1.50- 2.65; P < .0001); these daily users of high-potency cannabis had an onset an average of 6 years earlier than that of non-cannabis users. Daily use, especially of high-potency cannabis, drives the earlier onset of psychosis in cannabis users. © The Author 2013. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  6. Sensory, physical and chemical characteristics of cooked ham manufactured from rapidly chilled and earlier deboned M. semimembranosus.

    PubMed

    Tomović, Vladimir M; Jokanović, Marija R; Petrović, Ljiljana S; Tomović, Mila S; Tasić, Tatjana A; Ikonić, Predrag M; Sumić, Zdravko M; Sojić, Branislav V; Skaljac, Snežana B; Sošo, Milena M

    2013-01-01

    Effects of rapid chilling of carcasses (at -31°C in the first 3h of chilling, and then at 2-4°C) and earlier deboning (8h post-mortem), compared to rapid (till 24h post-mortem) and conventional chilling (at 2-4°C, till 24h post-mortem), on quality characteristics of pork M. semimebranosus and cooked ham were investigated. Quality measurements included pH value, colour (CIEL a b values) and total aerobic count of M. semimebranosus, as well as sensory (colour, juiciness, texture, and flavour), physical (pH value, colour - CIEL a b values and texture - Warner-Bratzler shear and penetration forces) and chemical (protein, total fat, and moisture content) characteristics of cooked ham. The cooked ham was manufactured from pieces of M. semimebranosus with ultimate lightness (CIEL value) lower than 50. Rapid chilling and earlier deboning significantly increased quantity of M. semimebranosus desirable for cooked ham manufacturing. Earlier start of pork fabrication did not affect important quality characteristics of cooked ham. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Trends of earlier palliative care consultation in advanced cancer patients receiving palliative radiation therapy.

    PubMed

    Chang, Sanders; Sigel, Keith; Goldstein, Nathan E; Wisnivesky, Juan; Dharmarajan, Kavita V

    2018-06-06

    The American Society of Clinical Oncology recommends that all patients with metastatic disease receive dedicated palliative care (PC) services early in their illness, ideally via interdisciplinary care teams. We investigated the time trends of specialty palliative care consultations from the date of metastatic cancer diagnosis among patients receiving palliative radiation therapy (PRT). A shorter time interval between metastatic diagnosis and first PC consultation suggests earlier involvement of palliative care in a patient's life with metastatic cancer. In this IRB-approved retrospective analysis, patients treated with PRT for solid tumors (bone and brain) at a single tertiary care hospital between 2010 and 2016 were included. Cohorts were arbitrarily established by metastatic diagnosis within approximately two-year intervals: (1) 1/1/2010-3/27/2012; (2) 3/28/2012-5/21/2014; and (3) 5/22/2014-12/31/2016. Cox-proportional hazards regression modelling was used to compare trends of PC consultation among cohorts. Of 284 patients identified, 184 patients received PC consultation, whereas 15 patients died before receiving a PC consult. Median follow-up time until an event or censor was 257 days (range: 1,900). Patients in the most recent cohort had a shorter median time to first PC consult (57 days) compared to those in the first (374 days) and second (186 days) cohorts. On multivariable analysis, patients in the third cohort were more likely to undergo a PC consultation earlier in their metastatic illness (HR: 1.8, 95% CI: 1.2,2.8). Over a six-year period, palliative care consultation occurred earlier for metastatic patients treated with PRT at our institution. Copyright © 2018. Published by Elsevier Inc.

  8. Considerations when conducting e-Delphi research: a case study.

    PubMed

    Toronto, Coleen

    2017-06-22

    Background E-Delphi is a way to access a geographically dispersed group of experts. It is similar to other Delphi methods but conducted online. E-research methodologies, such as the e-Delphi method, have yet to undergo significant critical discussion. Aim To highlight some of the challenges nurse researchers may wish to consider when using e-Delphi in their research. Discussion This paper provides details about the author's approach to conducting an e-Delphi study in which a group of health literacy nurse experts (n=41) used an online survey platform to identify and prioritise essential health literacy competencies for registered nurses. Conclusion This paper advances methodological discourse about e-Delphi by critically assessing an e-Delphi case study. The online survey platform used in this study was advantageous for the researcher and the experts: the experts could participate at any time and place where the internet was available; the researcher could efficiently access a national group of experts, track responses and analyse data in each round. Implications for practice E-Delphi studies create opportunities for nurse researchers to conduct research nationally and internationally. Before conducting an e-Delphi study, researchers should carefully consider the design and methods for collecting data, to avoid challenges that could potentially compromise the quality of the findings. Researchers are encouraged to publish details about their approaches to e-Delphi studies, to advance the state of the science.

  9. Earlier Age of Onset of Chronic Hypertension and Type 2 Diabetes Mellitus After a Hypertensive Disorder of Pregnancy or Gestational Diabetes Mellitus.

    PubMed

    Heida, Karst Y; Franx, Arie; van Rijn, Bas B; Eijkemans, Marinus J C; Boer, Jolanda M A; Verschuren, Monique W M; Oudijk, Martijn A; Bots, Michiel L; van der Schouw, Yvonne T

    2015-12-01

    A prospective cohort study was conducted to assess the impact of a history of hypertensive disorder of pregnancy (HDP) or gestational diabetes mellitus (GDM) on the risk and age of onset of hypertension, type 2 diabetes mellitus (T2D), and cardiovascular disease (CVD) later in life, independent of hypertension and T2D. Between 1993 and 1997, 22 265 ever-pregnant women were included from the European Prospective Investigation into Cancer and Nutrition-NL study, aged 20 to 70 years at baseline. Details on complications of pregnancy and known hypertension were obtained by questionnaire. Blood pressure was measured at enrollment. Participants were followed for the occurrence of CVD events. Data were analyzed using ANCOVA, multivariable logistic regression, and Cox proportional hazard (with HDP and GDM as time-dependent variables for T2D and CVD) models. At enrollment, women with a HDP reported diagnosis of hypertension 7.7 years earlier (95% confidence interval [CI] 6.9-8.5) and women with GDM reported diagnosis of T2D 7.7 years earlier (95% CI 5.8-9.6) than women without pregnancy complications. After adjustment for potential confounders, HDP was associated with presence of hypertension at enrollment (odds ratio 2.12, 95% CI 1.98-2.28) and onset of CVD later in life (hazard ratio 1.21, 95% CI 1.10-1.32). After including the intermediates hypertension and T2D in the model, the risk of CVD later in life decreased (hazard ratio 1.09, 95% CI 1.00-1.20). GDM was associated with an increased risk of developing T2D later in life (hazard ratio 3.68, 95% CI 2.77-4.90), but not with risk of CVD. HDP and GDM have a substantial impact on the risk of CVD and are potentially important indicators for preventive cardiovascular risk management. © 2015 American Heart Association, Inc.

  10. Do emotional support and classroom organization earlier in the year set the stage for higher quality instruction?

    PubMed

    Curby, Timothy W; Rimm-Kaufman, Sara E; Abry, Tashia

    2013-10-01

    Many teachers believe that providing greater emotional and organizational supports in the beginning of the year strengthens their ability to teach effectively as the year progresses. Some interventions, such as the Responsive Classroom (RC) approach, explicitly embed this sequence into professional development efforts. We tested the hypothesis that earlier emotional and organizational supports set the stage for improved instruction later in the year in a sample of third- and fourth-grade teachers enrolled in a randomized controlled trial of the RC approach. Further, we examined the extent to which the model generalized for teachers using varying levels of RC practices as well as whether or not teachers were in the intervention or control groups. Teachers' emotional, organizational, and instructional interactions were observed using the Classroom Assessment Scoring System (Pianta, La Paro, & Hamre, 2008) on five occasions throughout the year. Results indicated a reciprocal relation between emotional and instructional supports. Specifically, higher levels of emotional support earlier in the year predicted higher instructional support later in the year. Also, higher levels of instructional support earlier in the year predicted higher emotional support later in the year. Classroom organization was not found to have longitudinal associations with the other domains across a year. This pattern was robust when controlling for the use of RC practices as well as across intervention and control groups. Further, teachers' use of RC practices predicted higher emotional support and classroom organization throughout the year, suggesting the malleability of this teacher characteristic. Discussion highlights the connection between teachers' emotional and instructional supports and how the use of RC practices improves teachers' emotionally supportive interactions with students. Copyright © 2013 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights

  11. Maternal Attributions and Young Children's Conduct Problems: A Longitudinal Study

    ERIC Educational Resources Information Center

    Wilson, Charlotte; Gardner, Frances; Burton, Jennifer; Leung, Sarah

    2006-01-01

    The association between negative maternal attributions and child conduct problems is well established in correlational studies. However, little is known about how these variables influence each other over time. The present study examined patterns of prediction over time between maternal attributions and pre-school conduct problems. Sixty mothers…

  12. Is prenatal smoking associated with a developmental pattern of conduct problems in young boys?

    PubMed

    Wakschlag, Lauren S; Pickett, Kate E; Kasza, Kristen E; Loeber, Rolf

    2006-04-01

    Prenatal smoking is robustly associated with increased risk of conduct problems in offspring. Observational studies that provide detailed phenotypic description are critical for generating testable hypotheses about underlying processes through which the effects of prenatal smoking may operate. To this end, we use a developmental framework to examine the association of exposure with (1) oppositional defiant disorder and attention-deficit/hyperactivity disorder in young boys and (2) the pattern of delinquent behavior at adolescence. Using diagnostic measures and repeated measures of delinquency, we compare exposed and nonexposed boys from the youngest cohort of the Pittsburgh Youth Study (N = 448). Exposed boys were significantly more likely to (1) develop oppositional defiant disorder and comorbid oppositional defiant disorder-attention-deficit/hyperactivity disorder but not attention-deficit/hyperactivity disorder alone and (2) to have an earlier onset of significant delinquent behavior. The early emergence and developmental coherence of exposure-related conduct problems is striking and is consistent with a behavioral teratological model. Phenotypically, exposure-related conduct problems appear to be characterized by socially resistant and impulsively aggressive behavior. Whether prenatal smoking plays an etiological role in or is a risk marker for the development of conduct problems, exposed offspring are at increased risk of an early-starter pathway to conduct problems.

  13. Practical Aspects of Designing and Conducting Validation Studies Involving Multi-study Trials.

    PubMed

    Coecke, Sandra; Bernasconi, Camilla; Bowe, Gerard; Bostroem, Ann-Charlotte; Burton, Julien; Cole, Thomas; Fortaner, Salvador; Gouliarmou, Varvara; Gray, Andrew; Griesinger, Claudius; Louhimies, Susanna; Gyves, Emilio Mendoza-de; Joossens, Elisabeth; Prinz, Maurits-Jan; Milcamps, Anne; Parissis, Nicholaos; Wilk-Zasadna, Iwona; Barroso, João; Desprez, Bertrand; Langezaal, Ingrid; Liska, Roman; Morath, Siegfried; Reina, Vittorio; Zorzoli, Chiara; Zuang, Valérie

    This chapter focuses on practical aspects of conducting prospective in vitro validation studies, and in particular, by laboratories that are members of the European Union Network of Laboratories for the Validation of Alternative Methods (EU-NETVAL) that is coordinated by the EU Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM). Prospective validation studies involving EU-NETVAL, comprising a multi-study trial involving several laboratories or "test facilities", typically consist of two main steps: (1) the design of the validation study by EURL ECVAM and (2) the execution of the multi-study trial by a number of qualified laboratories within EU-NETVAL, coordinated and supported by EURL ECVAM. The approach adopted in the conduct of these validation studies adheres to the principles described in the OECD Guidance Document on the Validation and International Acceptance of new or updated test methods for Hazard Assessment No. 34 (OECD 2005). The context and scope of conducting prospective in vitro validation studies is dealt with in Chap. 4 . Here we focus mainly on the processes followed to carry out a prospective validation of in vitro methods involving different laboratories with the ultimate aim of generating a dataset that can support a decision in relation to the possible development of an international test guideline (e.g. by the OECD) or the establishment of performance standards.

  14. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... manner that precludes error in the recording and storage of data. (d) In animal studies where... available to a pathologist when examining that specimen histopathologically. (e) All data generated during the conduct of a study, except those that are generated by automated data collection systems, shall be...

  15. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... manner that precludes error in the recording and storage of data. (d) In animal studies where... available to a pathologist when examining that specimen histopathologically. (e) All data generated during the conduct of a study, except those that are generated by automated data collection systems, shall be...

  16. A reversal of the shift towards earlier spring phenology in several Mediterranean reptiles and amphibians during the 1998-2013 warming slowdown.

    PubMed

    Prodon, Roger; Geniez, Philippe; Cheylan, Marc; Devers, Florence; Chuine, Isabelle; Besnard, Aurelien

    2017-12-01

    Herps, especially amphibians, are particularly susceptible to climate change, as temperature tightly controls many parameters of their biological cycle-above all, their phenology. The timing of herps' activity or migration period-in particular the dates of their first appearance in spring and first breeding-and the shift to earlier dates in response to warming since the last quarter of the 20 th century has often been described up to now as a nearly monotonic trend towards earlier phenological events. In this study, we used citizen science data opportunistically collected on reptiles and amphibians in the northern Mediterranean basin over a period of 32 years to explore temporal variations in herp phenology. For 17 common species, we measured shifts in the date of the species' first spring appearance-which may be the result of current changes in climate-and regressed the first appearance date against temperatures and precipitations. Our results confirmed the expected overall trend towards earlier first spring appearances from 1983 to 1997, and show that the first appearance date of both reptiles and amphibians fits well with the temperature in late winter. However, the trend towards earlier dates was stopped or even reversed in most species between 1998 and 2013. We interpret this reversal as a response to cooling related to the North Atlantic Oscillation (NAO) in the late winter and early spring. During the positive NAO episodes, for certain species only (mainly amphibians), the effect of a warm weather, which tends to advance the phenology, seems to be counterbalanced by the adverse effects of the relative dryness. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  17. Return of hunger following a relatively high carbohydrate breakfast is associated with earlier recorded glucose peak and nadir

    PubMed Central

    Chandler-Laney, Paula C.; Morrison, Shannon A.; Goree, Laura Lee T.; Ellis, Amy C.; Casazza, Krista; Desmond, Renee; Gower, Barbara A

    2014-01-01

    Objective To test the hypothesis that a breakfast meal with high carbohydrate/ low fat results in an earlier increase in postprandial glucose and insulin, a greater decrease below baseline in postprandial glucose, and an earlier return of appetite, compared to a low carbohydrate/high fat meal. Design Overweight but otherwise healthy adults (n=64) were maintained on one of two eucaloric diets: high carbohydrate/low fat (HC/LF; 55:27:18% kcals from carbohydrate: fat: protein) versus low carbohydrate/high fat (LC/HF; 43:39:18% kcals from carbohydrate: fat: protein). After 4 weeks of acclimation to the diets, participants underwent a meal test during which circulating glucose and insulin and self-reported hunger and fullness, were measured before and after consumption of breakfast from their assigned diets. Results The LC/HF meal resulted in a later time at the highest and lowest recorded glucose, higher glucose concentrations at 3 and 4 hours post-meal, and lower insulin incremental area under the curve. Participants consuming the LC/HF meal reported lower appetite 3 and 4 hours following the meal, a response that was associated with the timing of the highest and lowest recorded glucose. Conclusions Modest increases in meal carbohydrate content at the expense of fat content may facilitate weight gain over the long-term by contributing to an earlier rise and fall of postprandial glucose concentrations and an earlier return of appetite. PMID:24819342

  18. Interplanetary double-shock ensembles with anomalous electrical conductivity

    NASA Technical Reports Server (NTRS)

    Dryer, M.

    1972-01-01

    Similarity theory is applied to the case of constant velocity, piston-driven, shock waves. This family of solutions, incorporating the interplanetary magnetic field for the case of infinite electric conductivity, represents one class of experimentally observed, flare-generated shock waves. This paper discusses the theoretical extension to flows with finite conductivity (presumably caused by unspecified modes of wave-particle interactions). Solutions, including reverse shocks, are found for a wide range of magnetic Reynolds numbers from one to infinity. Consideration of a zero and nonzero ambient flowing solar wind (together with removal of magnetic considerations) enables the recovery of earlier similarity solutions as well as numerical simulations. A limited comparison with observations suggests that flare energetics can be reasonably estimated once the shock velocity, ambient solar wind velocity and density, and ambient azimuthal Alfven Mach number are known.

  19. New Evidence: Data Documenting Parental Support for Earlier Sexuality Education

    ERIC Educational Resources Information Center

    Barr, Elissa M.; Moore, Michele J.; Johnson, Tammie; Forrest, Jamie; Jordan, Melissa

    2014-01-01

    Background: Numerous studies document support for sexuality education to be taught in high school, and often, in middle school. However, little research has been conducted addressing support for sexuality education in elementary schools. Methods: As part of the state Behavioral Risk Factor Surveillance System (BRFSS) Survey administration, the…

  20. Conductive Education: Feasibility Study on Developing a National Curriculum Plan for Those Working in Conductive Education in New Zealand.

    ERIC Educational Resources Information Center

    Wagner, Graham A.

    This study sought to determine whether there are national training needs among staff of conductive education programs in New Zealand. Conductive education is a unified system of education for children and adults with a motor disorder whose disability has been caused by damage to the central nervous system. The study, which focuses primarily on…

  1. Conduction studies of the normal sural nerve.

    PubMed

    Horowitz, S H; Krarup, C

    1992-03-01

    The sural nerve was studied orthodromically using the near-nerve technique in 273 normal subjects (155 females, 118 males) aged 5 to 90 years. The sensory action potential (SAP), evoked at the dorsum of the foot, was recorded at the lateral malleolus and midcalf, and at the midcalf when evoked at the lateral malleolus. In addition, the SAP was recorded at intermediate distal sites and at proximal sites at the popliteal fossa, the gluteal fold, and the S-1 root. The amplitude of the SAP recorded at midcalf was 32% higher in females than in males. This was probably due to volume-conduction properties, as differences between genders were less noticeable at more distal recording sites. The amplitude decreased steeply and exponentially with age. Conduction distance had a strong influence on the amplitude of the SAP, which decreased with increasing distance following a power relationship with an exponent of 1.4 to 1.7. This decrease was due to temporal dispersion with decreased summation and increased phase cancellation. The conduction velocity was slightly lower along the very distal course of the nerve than along more proximal segments.

  2. Fundamental principles of conducting a surgery economic analysis study.

    PubMed

    Kotsis, Sandra V; Chung, Kevin C

    2010-02-01

    The use of economic evaluation in surgery is scarce. Economic evaluation is used even less so in plastic surgery, in which health-related quality of life is of particular importance. This article, part of a tutorial series on evidence-based medicine, focuses on the fundamental principles of conducting a surgery economic analysis. The authors include the essential aspects of conducting a surgical cost-utility analysis by considering perspectives, costs, outcomes, and utilities. The authors also describe and give examples of how to conduct the analyses (including calculating quality-adjusted life-years and discounting), how to interpret the results, and how to report the results. Although economic analyses are not simple to conduct, a well-conducted one provides many rewards, such as recommending the adoption of a more effective treatment. For comparing and interpreting economic analysis publications, it is important that all studies use consistent methodology and report the results in a similar manner.

  3. Recovery from distal ulnar motor conduction block injury: serial EMG studies.

    PubMed

    Montoya, Liliana; Felice, Kevin J

    2002-07-01

    Acute conduction block injuries often result from nerve compression or trauma. The temporal pattern of clinical, electrophysiologic, and histopathologic changes following these injuries has been extensively studied in experimental animal models but not in humans. Our recent evaluation of a young man with an injury to the deep motor branch of the ulnar nerve following nerve compression from weightlifting exercises provided the opportunity to follow the course and recovery of a severe conduction block injury with sequential nerve conduction studies. The conduction block slowly and completely resolved, as did the clinical deficit, over a 14-week period. The reduction in conduction block occurred at a linear rate of -6.1% per week. Copyright 2002 Wiley Periodicals, Inc.

  4. Terahertz conductivity of MnSi thin films

    NASA Astrophysics Data System (ADS)

    Dodge, J.; Mohtashemi, Laleh; Farahani, Amir; Karhu, Eric; Monchesky, Theodore

    2013-03-01

    We present measurements of the low-frequency optical conductivity of MnSi thin films, using time-domain terahertz spectroscopy. At low temperatures and low frequencies, we extract the DC resistivity, scattering life time and plasma frequency from a Drude fit. We obtain a value of ωp ~= 1 . 0 eV, which can be used to estimate the renormalization coefficient through comparison with band theory. At higher temperatures, deviations from Drude behavior are observed, suggesting a loss of quasi-particle coherence. In the region of low temperatures and high frequencies, we see evidence for a crossover to the anomalous power law dependence observed by Mena et al. As the temperature increases, the anomalous frequency dependence becomes more pronounced, and the plasma frequency inferred from a Drude fit decreases dramatically. Above T ~ 50 K, σ2 (ω) develops a negative slope that is inconsistent with both a Drude model and the anomalous power law observed earlier, indicating a sharp pseudogap in the conductivity spectrum.

  5. Accessing Real-Life Episodic Information from Minutes versus Hours Earlier Modulates Hippocampal and High-Order Cortical Dynamics

    PubMed Central

    Chen, J.; Honey, C. J.; Simony, E.; Arcaro, M. J.; Norman, K. A.; Hasson, U.

    2016-01-01

    It is well known that formation of new episodic memories depends on hippocampus, but in real-life settings (e.g., conversation), hippocampal amnesics can utilize information from several minutes earlier. What neural systems outside hippocampus might support this minutes-long retention? In this study, subjects viewed an audiovisual movie continuously for 25 min; another group viewed the movie in 2 parts separated by a 1-day delay. Understanding Part 2 depended on retrieving information from Part 1, and thus hippocampus was required in the day-delay condition. But is hippocampus equally recruited to access the same information from minutes earlier? We show that accessing memories from a few minutes prior elicited less interaction between hippocampus and default mode network (DMN) cortical regions than accessing day-old memories of identical events, suggesting that recent information was available with less reliance on hippocampal retrieval. Moreover, the 2 groups evinced reliable but distinct DMN activity timecourses, reflecting differences in information carried in these regions when Part 1 was recent versus distant. The timecourses converged after 4 min, suggesting a time frame over which the continuous-viewing group may have relied less on hippocampal retrieval. We propose that cortical default mode regions can intrinsically retain real-life episodic information for several minutes. PMID:26240179

  6. Random sampling of constrained phylogenies: conducting phylogenetic analyses when the phylogeny is partially known.

    PubMed

    Housworth, E A; Martins, E P

    2001-01-01

    Statistical randomization tests in evolutionary biology often require a set of random, computer-generated trees. For example, earlier studies have shown how large numbers of computer-generated trees can be used to conduct phylogenetic comparative analyses even when the phylogeny is uncertain or unknown. These methods were limited, however, in that (in the absence of molecular sequence or other data) they allowed users to assume that no phylogenetic information was available or that all possible trees were known. Intermediate situations where only a taxonomy or other limited phylogenetic information (e.g., polytomies) are available are technically more difficult. The current study describes a procedure for generating random samples of phylogenies while incorporating limited phylogenetic information (e.g., four taxa belong together in a subclade). The procedure can be used to conduct comparative analyses when the phylogeny is only partially resolved or can be used in other randomization tests in which large numbers of possible phylogenies are needed.

  7. Electronic conductivity studies on oxyhalide glasses containing TMO

    NASA Astrophysics Data System (ADS)

    Vijayatha, D.; Viswanatha, R.; Sujatha, B.; Narayana Reddy, C.

    2016-05-01

    Microwave-assisted synthesis is cleaner, more economical and much faster than conventional methods. The development of new routes for the synthesis of solid materials is an integral part of material science and technology. The electronic conductivity studies on xPbCl2 - 60 PbO - (40-x) V2O5 (1 ≥ x ≤ 10) glass system has been carried out over a wide range of composition and temperature (300 K to 423 K). X-ray diffraction study confirms the amorphous nature of the samples. The Scanning electron microscopic studies reveal the formation of cluster like morphology in PbCl2 containing glasses. The d.c conductivity exhibits Arrhenius behaviour and increases with V2O5 concentration. Analysis of the results is interpreted in view Austin-Mott's small polaron model of electron transport. Activation energies calculated using regression analysis exhibit composition dependent trend and the variation is explained in view of the structure of lead-vanadate glass.

  8. Concurrent adversities among adolescents with conduct problems: the NAAHS study.

    PubMed

    Reigstad, Bjørn; Kvernmo, Siv

    2016-10-01

    Several studies have confirmed that maltreatment and abuse in childhood are related to conduct problems. Less is known about such relationships with concurrent adversities in adolescence and, also, when compared with other severe adversities and possible multiple additive effects. The study encompassed a community population of 4881 adolescents 15-16 years of age 50.1 % boys and 49.9 % girls. Youth with and without conduct problem scores within the deviant range on the Strength and Difficulties Questionnaire (SDQ) was compared on 12 concurrent adversities. Based on self-reports, 4.4 % of the adolescents had conduct problem scores within the deviant range and more girls (5.1 %) than boys (3.7 %). In the deviant conduct problem group, 65.1 % had experienced two or more concurrent adversities compared with 26.3 % of youths in the non-deviant group (OR 5.23, 95 % CI 3.91-7.01). Likewise, the deviant conduct problem group was from 1.71 to 8.43 times more at the risk of experiencing the different adversities. Parental mental health problems and experiences of violence were multivariately strongest associated with conduct problem scores within the deviant range on the SDQ. A strong multiple additive relationship with adversities was found. Two-thirds of youth with SDQ conduct problem scores within the deviant range reported two or more concurrent adversities. Clinicians should seek information about kinds and amount of possible traumatic adversities in youth with conduct problems and offer evidence based treatment.

  9. A Collection of Studies Conducted in Education about "Global Warming" Problem

    ERIC Educational Resources Information Center

    Bozdogan, Aykut Emre

    2011-01-01

    The studies global warming problem conducted in education discipline in the world and in Turkey were analysed for this study. The literature was reviewed extensively especially through the articles in the indexed journals of Ebsco Host, Science Direct, Taylor and Francis and Web of Science databases and this study was conducted according to the…

  10. Callous-Unemotional Traits Trajectories Interact with Earlier Conduct Problems and Executive Control to Predict Violence and Substance Use Among High Risk Male Adolescents.

    PubMed

    Baskin-Sommers, Arielle R; Waller, Rebecca; Fish, Ari M; Hyde, Luke W

    2015-11-01

    Callous-unemotional (CU) traits, conduct problems (CP), and deficits in executive control are all linked to the development of more severe antisocial behavior, including violence and substance use. Though previous research has examined the impact of these factors on antisocial outcomes, little work has examined trajectories of CU traits across adolescence and how these trajectories predict greater antisocial behavior in adulthood. Moreover, no study has assessed how severity of early CP and executive control may exacerbate these pathways and increase risk for later violence and substance use. The current study (a) identified trajectories of CU traits among a large, high-risk sample of adolescent males, (b) examined the relationship between CU traits trajectories and future violence and substance use, and (c) examined whether early CP and executive control moderated the effects of a high CU traits trajectory membership and high CP on violence and substance use. Results indicated that: (a) CU traits could be grouped into three stable trajectories across adolescence, (b) the 'high' CU traits trajectory, particularly in the presence of 'elevated' CP, was related to higher violence and substance use, over and above a variety of environmental risk factors, and (c) the effects the 'high' CU traits trajectory on both violence and substance and in the presence of 'elevated' CP was stronger among youth with high executive control. These findings highlight the utility of identifying subgroups of youth who differ on trajectories of CU traits for understanding the development and maintenance of severe antisocial behavior.

  11. Electrodiagnosis and nerve conduction studies.

    PubMed

    Posuniak, E A

    1984-08-01

    The use of electrodiagnostic techniques in evaluation of complaints in the lower extremities provides an objective method of assessment. A basic understanding of principles of neurophysiology, EMG and NCV methodology, and neuropathology of peripheral nerves greatly enhances physical diagnosis and improves the state of the art in treatment of the lower extremity, especially foot and ankle injuries. Familiarity with the method of reporting electrodiagnostic studies and appreciation of the electromyographer's interpretation of the EMG/NCV studies also reflects an enhanced fund of knowledge, skills, and attitudes as pertains to one's level of professional expertise. Information regarding the etiology of positive sharp waves, fibrillation potentials, fasciculation, and normal motor action potentials and conduction studies serves as a sound basis for the appreciation of the categories of nerve injury. Competence in understanding the degree of axonal or myelin function or dysfunction in a nerve improve one's effectiveness not only in medical/surgical treatment but in prognostication of recovery of function. A review of the entrapment syndromes in the lower extremity with emphasis on tarsal tunnel syndrome summarizes the most common nerve entrapments germane to the practice of podiatry. With regard to tarsal tunnel syndrome, the earliest electrodiagnostic study to suggest compression was reported to be the EMG of the foot and leg muscles, even before prolonged nerve latency was noted.

  12. Studies on conducting nanocomposite with gallium nitride-doped ferrite, part - III wasp-waist formation

    NASA Astrophysics Data System (ADS)

    Indrakanti, Rajani; Rao, V. Brahmaji; Kiran, C. Udaya

    2018-05-01

    We report the maiden experimental observation of the formation of Wasp-waists in the Hysteresis loop, of PPY Nanocomposite with GaN doped Ferrite. Earlier this phenomenon was reported in paleo magnetic and environmental magnetic studies. It is probably the very first time we report it in our Synthesized Nanocomposites. Details supported by data are presented. Parameters like Exchange Anisotropy, Multi Domain formation, Variations in Coercivity are suspected to be prominent causes for this occurrence. Systematic analysis of our data provides substantial evidence for the existence of the phenomenon.

  13. Comparative Study on Two Different Methods for Determination of Hydraulic Conductivity of HeLa Cells During Freezing.

    PubMed

    Li, Lei; Gao, Cai; Zhao, Gang; Shu, Zhiquan; Cao, Yunxia; Gao, Dayong

    2016-12-01

    The measurement of hydraulic conductivity of the cell membrane is very important for optimizing the protocol of cryopreservation and cryosurgery. There are two different methods using differential scanning calorimetry (DSC) to measure the freezing response of cells and tissues. Devireddy et al. presented the slow-fast-slow (SFS) cooling method, in which the difference of the heat release during the freezing process between the osmotically active and inactive cells is used to obtain the cell membrane hydraulic conductivity and activation energy. Luo et al. simplified the procedure and introduced the single-slow (SS) cooling protocol, which requires only one cooling process although different cytocrits are required for the determination of the membrane transport properties. To the best of our knowledge, there is still a lack of comparison of experimental processes and requirements for experimental conditions between these two methods. This study made a systematic comparison between these two methods from the aforementioned aspects in detail. The SFS and SS cooling methods mentioned earlier were utilized to obtain the reference hydraulic conductivity (L pg ) and activation energy (E Lp ) of HeLa cells by fitting the model to DSC data. With the SFS method, it was determined that L pg  = 0.10 μm/(min·atm) and E Lp  = 22.9 kcal/mol; whereas the results obtained by the SS cooling method showed that L pg  = 0.10 μm/(min·atm) and E Lp  = 23.6 kcal/mol. The results indicated that the values of the water transport parameters measured by two methods were comparable. In other words, the two parameters can be obtained by comparing the heat releases between two slow cooling processes of the same sample according to the SFS method. However, the SS method required analyzing heat releases of samples with different cytocrits. Thus, more experimental time was required.

  14. Advanced seasonal reproductive development in a male urban bird is reflected in earlier plasma luteinizing hormone rise but not energetic status.

    PubMed

    Davies, Scott; Behbahaninia, Hirbod; Giraudeau, Mathieu; Meddle, Simone L; Waites, Kyle; Deviche, Pierre

    2015-12-01

    Urban animals inhabit an environment considerably different than do their non-urban conspecifics, and to persist urban animals must adjust to these novel environments. The timing of seasonal reproductive development (i.e., growth of gonads and secondary sex organs) is a fundamental determinant of the breeding period and is frequently advanced in urban bird populations. However, the underlying mechanism(s) by which birds adjust the timing of reproductive development to urban areas remain(s) largely unknown. Here, we compared the timing of vernal reproductive development in free-ranging urban and non-urban male Abert's Towhees, Melozone aberti, in Phoenix, Arizona, USA, and tested the non-mutually exclusive hypotheses that earlier reproductive development is due to improved energetic status and/or earlier increase in endocrine activity of the reproductive system. We found that urban birds initiated testicular development earlier than non-urban birds, but this disparity was not associated with differences in body condition, fat stores, or innate immune performance. These results provide no support for the hypothesis that energetic constraints are responsible for delayed reproductive development of non-urban relative to urban male Abert's Towhees. Urban birds did, however, increase their plasma luteinizing hormone, but not plasma testosterone, earlier than non-urban birds. These findings suggest that adjustment to urban areas by Abert's Towhees involves increases in the endocrine activity of the anterior pituitary gland and/or hypothalamus earlier than non-urban towhees. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Perceived Parent-Child Relations, Conduct Problems, and Clinical Improvement Following the Treatment of Oppositional Defiant Disorder.

    PubMed

    Booker, Jordan A; Ollendick, Thomas H; Dunsmore, Julie C; Greene, Ross W

    2016-05-01

    Our objective in this study was to examine the moderating influence of parent-child relationship quality (as viewed by the child) on associations between conduct problems and treatment responses for children with oppositional defiant disorder (ODD). To date, few studies have considered children's perceptions of relationship quality with parents in clinical contexts even though extant studies show the importance of this factor in children's behavioral adjustment in non-clinical settings. In this study, 123 children (ages 7 - 14 years, 61.8% male, 83.7% white) who fulfilled DSM-IV criteria for ODD received one of two psychosocial treatments: Parent Management Training or Collaborative & Proactive Solutions. In an earlier study, both treatments were found to be effective and equivalent in treatment outcomes (Ollendick et al., in press). In the current study, pre-treatment maternal reports of conduct problems and pre-treatment child reports of relations with parents were used to predict outcomes in ODD symptoms and their severity following treatment. Elevated reports of children's conduct problems were associated with attenuated reductions in both ODD symptoms and their severity. Perceived relationship quality with parents moderated the ties between conduct problems and outcomes in ODD severity but not the number of symptoms. Mother reports of elevated conduct problems predicted attenuated treatment response only when children viewed relationship quality with their parents as poorer. When children viewed the relationship as higher quality, they did not show an attenuated treatment response, regardless of reported conduct problems. The current findings underscore the importance of children's perspectives in treatment response and reductions in externalizing child behaviors.

  16. Electronic conductivity studies on oxyhalide glasses containing TMO

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vijayatha, D.; Department of Physics, Gurunanak Institute of Technology, Hyderabad -040; Viswanatha, R.

    2016-05-06

    Microwave-assisted synthesis is cleaner, more economical and much faster than conventional methods. The development of new routes for the synthesis of solid materials is an integral part of material science and technology. The electronic conductivity studies on xPbCl{sub 2} – 60 PbO – (40-x) V{sub 2}O{sub 5} (1 ≥ x ≤ 10) glass system has been carried out over a wide range of composition and temperature (300 K to 423 K). X-ray diffraction study confirms the amorphous nature of the samples. The Scanning electron microscopic studies reveal the formation of cluster like morphology in PbCl{sub 2} containing glasses. The d.c conductivity exhibitsmore » Arrhenius behaviour and increases with V{sub 2}O{sub 5} concentration. Analysis of the results is interpreted in view Austin-Mott’s small polaron model of electron transport. Activation energies calculated using regression analysis exhibit composition dependent trend and the variation is explained in view of the structure of lead-vanadate glass.« less

  17. 5 CFR Appendix A to Subpart C of... - Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses of Deceased Separated Employees A...—Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses of...

  18. Whole plantar nerve conduction study with disposable strip electrodes.

    PubMed

    Hemmi, Shoji; Kurokawa, Katsumi; Nagai, Taiji; Okamoto, Toshio; Murakami, Tatsufumi; Sunada, Yoshihide

    2016-02-01

    A new method to evaluate whole plantar nerve conduction with disposable strip electrodes (DSEs) is described. Whole plantar compound nerve action potentials (CNAPs) were recorded at the ankle. DSEs were attached to the sole for simultaneous stimulation of medial and lateral plantar nerves. We also conducted medial plantar nerve conduction studies using an established method and compared the findings. Whole plantar CNAPs were recorded bilaterally from 32 healthy volunteers. Mean baseline to peak amplitude for CNAPs was 26.9 ± 11.8 μV, and mean maximum conduction velocity was 65.8 ± 8.3 m/s. The mean amplitude of CNAPs obtained by our method was 58.2% higher than that of CNAPs obtained by the Saeed method (26.9 μV vs. 17.0 μV; P < 0.0001). The higher mean amplitude of whole plantar CNAPs obtained by our method suggests that it enables CNAPs to be obtained easily, even in elderly people. © 2015 Wiley Periodicals, Inc.

  19. An Examination of University Conducting Faculty Members' Score Study Attitudes and Practices

    ERIC Educational Resources Information Center

    Silvey, Brian A.; Springer, D. Gregory; Eubanks, Stephen C.

    2016-01-01

    The purpose of this study was to examine university conducting teachers' attitudes about score study, the source materials they used to teach score study, their personal score study practices, and the score study approaches they taught their undergraduate conducting students. Respondents (N = 236) were members of the College Band Directors…

  20. Conducting Molecular Epidemiological Research in the Age of HIPAA: A Multi-Institutional Case-Control Study of Breast Cancer in African-American and European-American Women

    PubMed Central

    Ambrosone, Christine B.; Ciupak, Gregory L.; Bandera, Elisa V.; Jandorf, Lina; Bovbjerg, Dana H.; Zirpoli, Gary; Pawlish, Karen; Godbold, James; Furberg, Helena; Fatone, Anne; Valdimarsdottir, Heiddis; Yao, Song; Li, Yulin; Hwang, Helena; Davis, Warren; Roberts, Michelle; Sucheston, Lara; Demissie, Kitaw; Amend, Kandace L.; Tartter, Paul; Reilly, James; Pace, Benjamin W.; Rohan, Thomas; Sparano, Joseph; Raptis, George; Castaldi, Maria; Estabrook, Alison; Feldman, Sheldon; Weltz, Christina; Kemeny, Margaret

    2009-01-01

    Breast cancer in African-American (AA) women occurs at an earlier age than in European-American (EA) women and is more likely to have aggressive features associated with poorer prognosis, such as high-grade and negative estrogen receptor (ER) status. The mechanisms underlying these differences are unknown. To address this, we conducted a case-control study to evaluate risk factors for high-grade ER- disease in both AA and EA women. With the onset of the Health Insurance Portability and Accountability Act of 1996, creative measures were needed to adapt case ascertainment and contact procedures to this new environment of patient privacy. In this paper, we report on our approach to establishing a multicenter study of breast cancer in New York and New Jersey, provide preliminary distributions of demographic and pathologic characteristics among case and control participants by race, and contrast participation rates by approaches to case ascertainment, with discussion of strengths and weaknesses. PMID:19865486

  1. Smoking Status and the Five-Factor Model of Personality: Results of a Cross-Sectional Study Conducted in Poland

    PubMed Central

    Buczkowski, Krzysztof; Basinska, Małgorzata A.; Ratajska, Anna; Lewandowska, Katarzyna; Luszkiewicz, Dorota; Sieminska, Alicja

    2017-01-01

    Tobacco smoking is the single most important modifiable factor in increased morbidity and premature mortality. Numerous factors—including genetics, personality, and environment—affect the development and persistence of tobacco addiction, and knowledge regarding these factors could improve smoking cessation rates. This study compared personality traits between never, former, and current smokers, using the Five-Factor Model of Personality in a country with a turbulent smoking reduction process.: In this cross-sectional study, 909 Polish adults completed the Revised Neuroticism-Extraversion-Openness Personality Inventory. Our results showed that current smokers’ scores for extraversion, one of the five global dimensions of personality, were higher relative to never smokers. Neuroticism, openness to experience, agreeableness, and conscientiousness did not differ significantly according to smoking status. Facet analysis, which described each dimension in detail, showed that current smokers’ activity and excitement seeking (facets of extraversion) scores were higher relative to those of never and former smokers. In turn, current smokers’ dutifulness and deliberation (facets of conscientiousness) scores were lower than those found in former and never smokers. Never smokers scored the highest in self-consciousness (a facet of neuroticism) and compliance (a component of agreeableness). The study conducted among Polish individuals showed variation in personality traits according to their smoking status; however, this variation differed from that reported in countries in which efforts to reduce smoking had begun earlier relative to Poland. Knowledge regarding personality traits could be useful in designing smoking prevention and cessation programs tailored to individuals’ needs. PMID:28134805

  2. Smoking Status and the Five-Factor Model of Personality: Results of a Cross-Sectional Study Conducted in Poland.

    PubMed

    Buczkowski, Krzysztof; Basinska, Małgorzata A; Ratajska, Anna; Lewandowska, Katarzyna; Luszkiewicz, Dorota; Sieminska, Alicja

    2017-01-27

    Tobacco smoking is the single most important modifiable factor in increased morbidity and premature mortality. Numerous factors-including genetics, personality, and environment-affect the development and persistence of tobacco addiction, and knowledge regarding these factors could improve smoking cessation rates. This study compared personality traits between never, former, and current smokers, using the Five-Factor Model of Personality in a country with a turbulent smoking reduction process. : In this cross-sectional study, 909 Polish adults completed the Revised Neuroticism-Extraversion-Openness Personality Inventory. Our results showed that current smokers' scores for extraversion, one of the five global dimensions of personality, were higher relative to never smokers. Neuroticism, openness to experience, agreeableness, and conscientiousness did not differ significantly according to smoking status. Facet analysis, which described each dimension in detail, showed that current smokers' activity and excitement seeking (facets of extraversion) scores were higher relative to those of never and former smokers. In turn, current smokers' dutifulness and deliberation (facets of conscientiousness) scores were lower than those found in former and never smokers. Never smokers scored the highest in self-consciousness (a facet of neuroticism) and compliance (a component of agreeableness). The study conducted among Polish individuals showed variation in personality traits according to their smoking status; however, this variation differed from that reported in countries in which efforts to reduce smoking had begun earlier relative to Poland. Knowledge regarding personality traits could be useful in designing smoking prevention and cessation programs tailored to individuals' needs.

  3. Calculation and Study of Graphene Conductivity Based on Terahertz Spectroscopy

    NASA Astrophysics Data System (ADS)

    Feng, Xiaodong; Hu, Min; Zhou, Jun; Liu, Shenggang

    2017-07-01

    Based on terahertz time-domain spectroscopy system and two-dimensional scanning control system, terahertz transmission and reflection intensity mapping images on a graphene film are obtained, respectively. Then, graphene conductivity mapping images in the frequency range 0.5 to 2.5 THz are acquired according to the calculation formula. The conductivity of graphene at some typical regions is fitted by Drude-Smith formula to quantitatively compare the transmission and reflection measurements. The results show that terahertz reflection spectroscopy has a higher signal-to-noise ratio with less interference of impurities on the back of substrates. The effect of a red laser excitation on the graphene conductivity by terahertz time-domain transmission spectroscopy is also studied. The results show that the graphene conductivity in the excitation region is enhanced while that in the adjacent area is weakened which indicates carriers transport in graphene under laser excitation. This paper can make great contribution to the study on graphene electrical and optical properties in the terahertz regime and help design graphene terahertz devices.

  4. Electrical and Nonlinear Optical Studies of Specific Organic Molecular and Nonconjugated Conductive Polymeric Systems

    NASA Astrophysics Data System (ADS)

    Narayanan, Ananthakrishnan

    applications in electro-optics and photonics. Electron paramagnetic resonance measurements on poly(beta-pinene) before and after doping with iodine are reported in this work. The EPR signal of this polymer increases proportionally with the iodine concentration due to the formation of cation radicals upon doping and charge-transfer. The results agree well with the doping mechanism of nonconjugated conducting polymers discussed earlier in literature. Hyperfine splitting in heavily doped polymers is observed due to the reduced distance between the cation radical and the iodine anion. Off-resonant electro-optic measurements in doped poly(beta-pinene) at 790nm, 800nm, 810nm and 1.55microm using field-induced birefringence technique have been studied. The results show that this material exhibits the highest cubic nonlinearities of all known materials. The Kerr coefficient measured at 1.55microm is 1.6x10-10 m/V2 which is about 30 times higher than that of conjugated polymers. Results of two photon measurements in this doped polymer using pump-probe technique with a pulsed, mode-locked (150 fs pulses) beam from a Ti-Sapphire laser are reported. The measured value of alpha2 at 790 nm and 795 nm were found to be 2.28+/-0.1 cm/MW and 2.5+/-0.1 cm/MW respectively. The data confirms that the nonlinearity in this material is ultrafast and electronic in nature. Such large nonlinearities in these materials are attributed the charge confinement in these materials in a sub-nanometer domain (upon doping) resulting in a metal-like quantum dot structure. Photovoltaic measurements in a composite involving poly(beta-pinene) and C60 are discussed. This is the first time a nonconjugated conducting polymer based photovoltaic cell has been fabricated. A composite involving 4% C60 by weight produced a photovoltage of 280mV for an incident light intensity of 6mW/sq.cm. These low cost devices have applications in solar cells, photodetectors etc. A nonlinear optical waveguide was prepared by casting a thin

  5. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... shall accompany the specimen in a manner that precludes error in the recording and storage of data. (d.... (e) All data generated during the conduct of a study, except those that are generated by automated data collection systems, shall be recorded directly, promptly, and legibly in ink. All data entries...

  6. M-Mode Ultrasound Reveals Earlier Gluteus Minimus Activity in Individuals With Chronic Hip Pain During a Step-down Task.

    PubMed

    Dieterich, Angela V; Deshon, Louise; Strauss, Geoffrey R; McKay, Jan; Pickard, Christine M

    2016-04-01

    Controlled laboratory study. The hip abductor muscles are important hip joint stabilizers. Hip joint pain may alter muscle recruitment. Motion-mode (M-mode) ultrasound enables noninvasive measurements of the onset of deep and superficial muscle motion, which is associated with activation onset. To compare (1) the onset of superficial and deep gluteus medius and gluteus minimus muscle motion relative to the instant of peak ground reaction force and (2) the level of swing-phase muscle motion during step-down between subjects with chronic hip pain and controls using M-mode ultrasound. Thirty-five subjects with anterior, nontraumatic hip pain for more than 6 months (mean ± SD age, 54 ± 9 years) and 35 controls (age, 57 ± 7 years) were scanned on the lateral hip of the leading leg during frontal step-down onto a force platform using M-mode ultrasound. Computerized motion detection with the Teager-Kaiser energy operator was applied on the gluteus minimus and the deep and superficial gluteus medius to determine the time lag between muscle motion onset and instant of peak ground reaction force and the level of gluteus minimus motion during the swing phase. Time lags and motion levels were averaged per subject, and t tests were used to determine between-group differences. In participants with hip pain, gluteus minimus motion onset was 103 milliseconds earlier (P = .002) and superficial gluteus medius motion was 70 milliseconds earlier (P = .047) than those in healthy control participants. The level of gluteus minimus swing-phase motion was higher with pain (P = .006). Increased gluteus minimus motion during the swing phase and earlier gluteus minimus and superficial gluteus medius motion in individuals with hip pain suggest an overall increase of muscle activity, possibly a protective behavior.

  7. Antiretroviral treatment-based cost saving interventions may offset expenses for new patients and earlier treatment start.

    PubMed

    Angeletti, C; Pezzotti, P; Antinori, A; Mammone, A; Navarra, A; Orchi, N; Lorenzini, P; Mecozzi, A; Ammassari, A; Murachelli, S; Ippolito, G; Girardi, E

    2014-03-01

    Combination antiretroviral therapy (cART) has become the main driver of total costs of caring for persons living with HIV (PLHIV). The present study estimated the short/medium-term cost trends in response to the recent evolution of national guidelines and regional therapeutic protocols for cART in Italy. We developed a deterministic mathematical model that was calibrated using epidemic data for Lazio, a region located in central Italy with about six million inhabitants. In the Base Case Scenario, the estimated number of PLHIV in the Lazio region increased over the period 2012-2016 from 14 414 to 17 179. Over the same period, the average projected annual cost for treating the HIV-infected population was €147.0 million. An earlier cART initiation resulted in a rise of 2.3% in the average estimated annual cost, whereas an increase from 27% to 50% in the proportion of naïve subjects starting cART with a nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimen resulted in a reduction of 0.3%. Simplification strategies based on NNRTIs co-formulated in a single tablet regimen and protease inhibitor/ritonavir-boosted monotherapy produced an overall reduction in average annual costs of 1.5%. A further average saving of 3.3% resulted from the introduction of generic antiretroviral drugs. In the medium term, cost saving interventions could finance the increase in costs resulting from the inertial growth in the number of patients requiring treatment and from the earlier treatment initiation recommended in recent guidelines. © 2013 British HIV Association.

  8. 37 CFR 1.78 - Claiming benefit of earlier filing date and cross-references to other applications.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Claiming benefit of earlier filing date and cross-references to other applications. 1.78 Section 1.78 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN...

  9. 37 CFR 1.78 - Claiming benefit of earlier filing date and cross-references to other applications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Claiming benefit of earlier filing date and cross-references to other applications. 1.78 Section 1.78 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN...

  10. Earlier Vegetation Activity Onset Enhances Springtime Water-use Efficiency in Temperate and Boreal Ecosystems

    NASA Astrophysics Data System (ADS)

    Jin, J.; Wang, Y.

    2017-12-01

    Ecosystem-scale water-use efficiency (EWUE), defined as the ratio of gross primary productivity (GPP) to evapotranspiration (ET), is an important indicator for understanding how water couples with the carbon cycle under global change. Relationships between EWUE and abiotic environmental factors (e.g. climatic factors, atmospheric CO2concentration and nitrogen deposition) have been widely investigated, but the variations in EWUE in response to biotic controls remain little understood. Here, we argue that phenology plays an important role in the regulation of EWUE by analyzing springtime EWUE responses to variability of the GPP-based vegetation activity onset (VAO) in temperate and boreal ecosystems using both satellite and flux-tower observations. Based on MODIS productions during 2000-2014, we found that spring EWUE widely significantly increased with the earlier VAO mainly in the mid- and high latitudes (over 50°N), southwestern China and mid-western North America. When AVO advanced a 10-day, the spring EWUE would increase on average by 0.17±0.09 g C kg-1 H2O in temperate and continental climates after removing the effect of environmental factors. The main response patterns of EWUE to phenology suggest that an increase in spring EWUE with an earlier VAO are mainly because the increase in GPP is relatively larger in magnitude compared to that of ET, or due to an increase in GPP accompanied by a decrease in ET, resulting from an advanced VAO. The credibility of the results is also supported by the local-scale observations. By analyzing 66 site-years of flux and meteorological data obtained from 8 temperate deciduous broadleaf forest sites across North America and Europe, spring EWUE increased 0.42±0.08 g C kg-1 H2O with a 10-day advance of VAO across all sites after controlling for environmental factors, mainly because an earlier VAO could lead to a steeper increase in GPP than in ET. Our results and conclusions highlight that phenological factors cannot be

  11. Cost-Effectiveness of Earlier Initiation of Antiretroviral Therapy for Uninsured HIV-Infected Adults

    PubMed Central

    Schackman, Bruce R.; Goldie, Sue J.; Weinstein, Milton C.; Losina, Elena; Zhang, Hong; Freedberg, Kenneth A.

    2001-01-01

    Objectives. This study was designed to examine the societal cost-effectiveness and the impact on government payers of earlier initiation of antiretroviral therapy for uninsured HIV-infected adults. Methods. A state-transition simulation model of HIV disease was used. Data were derived from the Multicenter AIDS Cohort Study, published randomized trials, and medical care cost estimates for all government payers and for Massachusetts, New York, and Florida. Results. Quality-adjusted life expectancy increased from 7.64 years with therapy initiated at 200 CD4 cells/μL to 8.21 years with therapy initiated at 500 CD4 cells/μL. Initiating therapy at 500 CD4/μL was a more efficient use of resources than initiating therapy at 200 CD4/μL and had an incremental cost-effectiveness ratio of $17 300 per quality-adjusted life-year gained, compared with no therapy. Costs to state payers in the first 5 years ranged from $5500 to $24 900 because of differences among the states in the availability of federal funds for AIDS drug assistance programs. Conclusions. Antiretroviral therapy initiated at 500 CD4 cells/μL is cost-effective from a societal perspective compared with therapy initiated later. States should consider Medicaid waivers to expand access to early therapy. PMID:11527782

  12. Synthesis, characterization and DC conductivity studies of conducting polyaniline/PVA/Fly ash polymer composites

    NASA Astrophysics Data System (ADS)

    Revanasiddappa, M.; Swamy, D. Siddalinga; Vinay, K.; Ravikiran, Y. T.; Raghavendra, S. C.

    2018-05-01

    The present work is an investigation of dc conduction behaviour of conducting polyaniline/fly ash nano particles blended in polyvinyl Alcohol (PANI/PVA/FA) synthesized via in-situ polymerization technique using (NH4)2S2O8 as an oxidising agent with varying fly ash cenosphere by 10, 20, 30, 40 and 50 wt%. The structural characterization of the synthesised polymer composites was examined using FT-IR, XRD and SEM techniques. Dc conductivity as a function of temperature has been measured in the temperature range from 302K - 443K. The increase of conductivity with increasing temperature reveals semiconducting behaviour of the composites and shows an evidence for the transport properties of the composites.

  13. The case for earlier cochlear implantation in postlingually deaf adults.

    PubMed

    Dowell, Richard C

    2016-01-01

    This paper aimed to estimate the difference in speech perception outcomes that may occur due to timing of cochlear implantation in relation to the progression of hearing loss. Data from a large population-based sample of adults with acquired hearing loss using cochlear implants (CIs) was used to estimate the effects of duration of hearing loss, age, and pre-implant auditory skills on outcomes for a hypothetical standard patient. A total of 310 adults with acquired severe/profound bilateral hearing loss who received a CI in Melbourne, Australia between 1994 and 2006 provided the speech perception data and demographic information to derive regression equations for estimating CI outcomes. For a hypothetical CI candidate with progressive sensorineural hearing loss, the estimates of speech perception scores following cochlear implantation are significantly better if implantation occurs relatively soon after onset of severe hearing loss and before the loss of all functional auditory skills. Improved CI outcomes and quality of life benefit may be achieved for adults with progressive severe hearing loss if they are implanted earlier in the progression of the pathology.

  14. Integrated Tree-Ring-Radiocarbon High-Resolution Timeframe to Resolve Earlier Second Millennium BCE Mesopotamian Chronology.

    PubMed

    Manning, Sturt W; Griggs, Carol B; Lorentzen, Brita; Barjamovic, Gojko; Ramsey, Christopher Bronk; Kromer, Bernd; Wild, Eva Maria

    2016-01-01

    500 years of ancient Near Eastern history from the earlier second millennium BCE, including such pivotal figures as Hammurabi of Babylon, Šamši-Adad I (who conquered Aššur) and Zimrilim of Mari, has long floated in calendar time subject to rival chronological schemes up to 150+ years apart. Texts preserved on clay tablets provide much information, including some astronomical references, but despite 100+ years of scholarly effort, chronological resolution has proved impossible. Documents linked with specific Assyrian officials and rulers have been found and associated with archaeological wood samples at Kültepe and Acemhöyük in Turkey, and offer the potential to resolve this long-running problem. Here we show that previous work using tree-ring dating to place these timbers in absolute time has fundamental problems with key dendrochronological crossdates due to small sample numbers in overlapping years and insufficient critical assessment. To address, we have integrated secure dendrochronological sequences directly with radiocarbon (14C) measurements to achieve tightly resolved absolute (calendar) chronological associations and identify the secure links of this tree-ring chronology with the archaeological-historical evidence. The revised tree-ring-sequenced 14C time-series for Kültepe and Acemhöyük is compatible only with the so-called Middle Chronology and not with the rival High, Low or New Chronologies. This finding provides a robust resolution to a century of uncertainty in Mesopotamian chronology and scholarship, and a secure basis for construction of a coherent timeframe and history across the Near East and East Mediterranean in the earlier second millennium BCE. Our re-dating also affects an unusual tree-ring growth anomaly in wood from Porsuk, Turkey, previously tentatively associated with the Minoan eruption of the Santorini volcano. This tree-ring growth anomaly is now directly dated ~1681-1673 BCE (68.2% highest posterior density range), ~20

  15. Integrated Tree-Ring-Radiocarbon High-Resolution Timeframe to Resolve Earlier Second Millennium BCE Mesopotamian Chronology

    PubMed Central

    Griggs, Carol B.; Lorentzen, Brita; Barjamovic, Gojko; Ramsey, Christopher Bronk; Kromer, Bernd; Wild, Eva Maria

    2016-01-01

    500 years of ancient Near Eastern history from the earlier second millennium BCE, including such pivotal figures as Hammurabi of Babylon, Šamši-Adad I (who conquered Aššur) and Zimrilim of Mari, has long floated in calendar time subject to rival chronological schemes up to 150+ years apart. Texts preserved on clay tablets provide much information, including some astronomical references, but despite 100+ years of scholarly effort, chronological resolution has proved impossible. Documents linked with specific Assyrian officials and rulers have been found and associated with archaeological wood samples at Kültepe and Acemhöyük in Turkey, and offer the potential to resolve this long-running problem. Here we show that previous work using tree-ring dating to place these timbers in absolute time has fundamental problems with key dendrochronological crossdates due to small sample numbers in overlapping years and insufficient critical assessment. To address, we have integrated secure dendrochronological sequences directly with radiocarbon (14C) measurements to achieve tightly resolved absolute (calendar) chronological associations and identify the secure links of this tree-ring chronology with the archaeological-historical evidence. The revised tree-ring-sequenced 14C time-series for Kültepe and Acemhöyük is compatible only with the so-called Middle Chronology and not with the rival High, Low or New Chronologies. This finding provides a robust resolution to a century of uncertainty in Mesopotamian chronology and scholarship, and a secure basis for construction of a coherent timeframe and history across the Near East and East Mediterranean in the earlier second millennium BCE. Our re-dating also affects an unusual tree-ring growth anomaly in wood from Porsuk, Turkey, previously tentatively associated with the Minoan eruption of the Santorini volcano. This tree-ring growth anomaly is now directly dated ~1681–1673 BCE (68.2% highest posterior density range), ~20

  16. Understanding Violence in Contemporary and Earlier Gangs: An Exploratory Application of the Theory of Reasoned Action.

    ERIC Educational Resources Information Center

    Evans, Judy P.; Taylor, Jerome

    1995-01-01

    Reviews the theory of reasoned action to demonstrate how it can be applied to understanding gang violence, and illustrates its potential applicability to a pilot sample of 30 contemporary and 18 earlier gangs living in a large metropolitan community. Results indicate this theory has been helpful in explaining higher levels of violence in…

  17. Conducting feasibilities in clinical trials: an investment to ensure a good study.

    PubMed

    Rajadhyaksha, Viraj

    2010-07-01

    Conducting clinical trial feasibility is one of the first steps in clinical trial conduct. This process includes assessing internal and environmental capacity, alignment of the clinical trial in terms of study design, dose of investigational product, comparator, patient type, with the local environment and assessing potential of conducting clinical trial in a specific country. A robust feasibility also ensures a realistic assessment and capability to conduct the clinical trial. For local affiliates of pharmaceutical organizations, and contract research organizations, this is a precursor to study placement and influences the decision of study placement. This article provides details on different types of feasibilities, information which is to be included and relevance of each. The article also aims to provide practical hands-on suggestions to make feasibilities more realistic and informative.

  18. A genetically informative developmental study of the relationship between conduct disorder and peer deviance in males

    PubMed Central

    Kendler, K. S.; Jacobson, K.; Myers, J. M.; Eaves, L. J.

    2014-01-01

    Background Conduct disorder (CD) and peer deviance (PD) both powerfully predict future externalizing behaviors. Although levels of CD and PD are strongly correlated, the causal relationship between them has remained controversial and has not been examined by a genetically informative study. Method Levels of CD and PD were assessed in 746 adult male–male twin pairs at personal interview for ages 8–11, 12–14 and 15–17 years using a life history calendar. Model fitting was performed using the Mx program. Results The best-fit model indicated an active developmental relationship between CD and PD including forward transmission of both traits over time and strong causal relationships between CD and PD within time periods. The best-fit model indicated that the causal relationship for genetic risk factors was from CD to PD and was constant over time. For common environmental factors, the causal pathways ran from PD to CD and were stronger in earlier than later age periods. Conclusions A genetically informative model revealed causal pathways difficult to elucidate by other methods. Genes influence risk for CD, which, through social selection, impacts on the deviance of peers. Shared environment, through family and community processes, encourages or discourages adolescent deviant behavior, which, via social influence, alters risk for CD. Social influence is more important than social selection in childhood, but by late adolescence social selection becomes predominant. These findings have implications for prevention efforts for CD and associated externalizing disorders. PMID:17935643

  19. Hemodynamic parameters change earlier than tissue oxygen tension in hemorrhage.

    PubMed

    Pestel, Gunther J; Fukui, Kimiko; Kimberger, Oliver; Hager, Helmut; Kurz, Andrea; Hiltebrand, Luzius B

    2010-05-15

    Untreated hypovolemia results in impaired outcome. This study tests our hypothesis whether general hemodynamic parameters detect acute blood loss earlier than monitoring parameters of regional tissue beds. Eight pigs (23-25 kg) were anesthetized and mechanically ventilated. A pulmonary artery catheter and an arterial catheter were inserted. Tissue oxygen tension was measured with Clark-type electrodes in the jejunal and colonic wall, in the liver, and subcutaneously. Jejunal microcirculation was assessed by laser Doppler flowmetry (LDF). Intravascular volume was optimized using difference in pulse pressure (dPP) to keep dPP below 13%. Sixty minutes after preparation, baseline measurements were taken. At first, 5% of total blood volume was withdrawn, followed by another 5% increment, and then in 10% increments until death. After withdrawal of 5% of estimated blood volume, dPP increased from 6.1% +/- 3.0% to 20.8% +/- 2.7% (P < 0.01). Mean arterial pressure (MAP), mean pulmonary artery pressure (PAP) and pulmonary artery occlusion pressure (PAOP) decreased with a blood loss of 10% (P < 0.01). Cardiac output (CO) changed after a blood loss of 20% (P < 0.05). Tissue oxygen tension in central organs, and blood flow in the jejunal muscularis decreased (P < 0.05) after a blood loss of 20%. Tissue oxygen tension in the skin, and jejunal mucosa blood flow decreased (P < 0.05) after a blood loss of 40% and 50%, respectively. In this hemorrhagic pig model systemic hemodynamic parameters were more sensitive to detect acute hypovolemia than tissue oxygen tension measurements or jejunal LDF measurements. Acute blood loss was detected first by dPP. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  20. Presetting ECG electrodes for earlier heart rate detection in the delivery room.

    PubMed

    Gulati, Rashmi; Zayek, Michael; Eyal, Fabien

    2018-07-01

    To determine whether heart rate (HR) could be detected earlier than by pulse oximeter (POX), using a novel method of application of electrocardiogram (ECG) electrodes during neonatal resuscitation in the delivery room. ECG electrodes were set before delivery to be applied to the back of infants' thorax. Time to detect HR was recorded as soon as a numerical HR along with a recognizable and persistent QRS complex was observed on ECG monitor (HRECG) and a plethysmographic waveform was seen on POX monitor (HRPOX). Out of 334 infants, 49 were <31 weeks of gestational age. Overall, the median (interquartile range, IQR) time to detect HRECG was significantly shorter [29 (5, 60) seconds] than time by POX [60 (45,120) seconds], (p < 0.001). Similarly, in <31-week infants, the median (IQR) time to detect HRECG was 10 (2, 40) seconds compared to 60 (30,120) seconds by POX, (p < 0.001). Failure to have HR detected by 1 minute occurred in 30%, 54% and 20% of infants by ECG, POX and either of the devices, respectively. In the delivery room, electrodes applied by the study method are more effective than pulse oximetry in providing the neonatal team with timely HR information that is necessary for proper resuscitative actions. Published by Elsevier B.V.

  1. Earlier Snowmelt Changes the Ratio Between Early and Late Season Forest Productivity

    NASA Astrophysics Data System (ADS)

    Knowles, J. F.; Molotch, N. P.; Trujillo, E.; Litvak, M. E.

    2017-12-01

    Future projections of declining snowpack and increasing potential evaporation associated with climate warming are predicted to advance the timing of snowmelt in mountain ecosystems globally. This scenario has direct implications for snowmelt-driven forest productivity, but the net effect of temporally shifting moisture dynamics is unknown with respect to the annual carbon balance. Accordingly, this study uses both satellite- and tower-based observations to document the forest productivity response to snowpack and potential evaporation variability between 1989 and 2012 throughout the southern Rocky Mountain ecoregion, USA. These results show that a combination of low snow accumulation and record high potential evaporation in 2012 resulted in the 34-year minimum ecosystem productivity that could be indicative of future conditions. Moreover, early and late season productivity were significantly and inversely related, suggesting that future shifts toward earlier or reduced snowmelt could increase late-season moisture stress to vegetation and thus restrict productivity despite a longer growing season. This relationship was further subject to modification by summer precipitation, and the controls on the early/late season productivity ratio are explored within the context of ecosystem carbon storage in the future. Any perturbation to the carbon cycle at this scale represents a potential feedback to climate change since snow-covered forests represent an important global carbon sink.

  2. Electrical conductivity modeling and experimental study of densely packed SWCNT networks.

    PubMed

    Jack, D A; Yeh, C-S; Liang, Z; Li, S; Park, J G; Fielding, J C

    2010-05-14

    Single-walled carbon nanotube (SWCNT) networks have become a subject of interest due to their ability to support structural, thermal and electrical loadings, but to date their application has been hindered due, in large part, to the inability to model macroscopic responses in an industrial product with any reasonable confidence. This paper seeks to address the relationship between macroscale electrical conductivity and the nanostructure of a dense network composed of SWCNTs and presents a uniquely formulated physics-based computational model for electrical conductivity predictions. The proposed model incorporates physics-based stochastic parameters for the individual nanotubes to construct the nanostructure such as: an experimentally obtained orientation distribution function, experimentally derived length and diameter distributions, and assumed distributions of chirality and registry of individual CNTs. Case studies are presented to investigate the relationship between macroscale conductivity and nanostructured variations in the bulk stochastic length, diameter and orientation distributions. Simulation results correspond nicely with those available in the literature for case studies of conductivity versus length and conductivity versus diameter. In addition, predictions for the increasing anisotropy of the bulk conductivity as a function of the tube orientation distribution are in reasonable agreement with our experimental results. Examples are presented to demonstrate the importance of incorporating various stochastic characteristics in bulk conductivity predictions. Finally, a design consideration for industrial applications is discussed based on localized network power emission considerations and may lend insight to the design engineer to better predict network failure under high current loading applications.

  3. Apparatus for in situ prediction of the thermal conductivity of fiberglass batts using acoustic propagation constant

    NASA Astrophysics Data System (ADS)

    Tinianov, Brandon D.; Nakagawa, Masami; Muñoz, David R.

    2006-02-01

    This article describes a novel technique for the measurement of the thermal conductivity of low-density (12-18kg/m3) fiberglass insulation and other related fibrous insulation materials using a noninvasive acoustic apparatus. The experimental method is an extension of earlier acoustic methods based upon the evaluation of the propagation constant from the acoustic pressure transfer function across the test material. To accomplish this, an analytical model is employed that describes the behavior of sound waves at the outlet of a baffled waveguide. The model accounts for the behavior of the mixed impedance interface introduced by the test material. Current results show that the technique is stable for a broad range of absorber thicknesses and densities. Experimental results obtained in the laboratory show excellent correlation between the thermal conductivity and both the real and imaginary components of the propagation constant. Correlation of calculated propagation constant magnitude versus measured thermal conductivity gave an R2 of 0.94 for the bulk density range (12-18kg/m3) typical for manufactured fiberglass batt materials. As an improvement to earlier acoustic techniques, measurement is now possible in noisy manufacturing environments with a moving test material. Given the promise of such highly correlated measurements in a robust method, the acoustic technique is well suited to continuously measure the thermal conductivity of the material during its production, replacing current expensive off-line methods. Test cycle time is reduced from hours to seconds.

  4. Reanalysis of the occurrence of back pain among construction workers: modelling for the interdependent effects of heavy physical work, earlier back accidents, and aging.

    PubMed

    Nurminen, M

    1997-11-01

    To re-examine the relation between heavy physical work and the occurrence of sciatic pain among construction workers reported previously to be absent in an epidemiological study. METHODS-Poisson log linear regression was used to model for the frequency of sciatic pain among concrete reinforcement workers and maintenance house painters with adjustment for the interactive effects of earlier back accidents and aging that modified the relation. Concrete reinforcement work not only had a direct effect on the frequency of sciatic pain, but it also contributed significantly to the risk indirectly through earlier back accidents. The risk of sciatic pain increased from age 25 to 54 in a different manner for a worker depending on his occupational group and record of back accidents. Epidemiological studies on low back pain need to be analysed with sound methodology. This is important in view of future meta-analyses that will be performed for the purpose of providing guidelines on the prevention of back disorders in heavy physical work.

  5. Field evidence for earlier leaf-out dates in alpine grassland on the eastern Tibetan Plateau from 1990 to 2006.

    PubMed

    Zhou, H K; Yao, B Q; Xu, W X; Ye, X; Fu, J J; Jin, Y X; Zhao, X Q

    2014-08-01

    Worldwide, many plant species are experiencing an earlier onset of spring phenophases due to climate warming. Rapid recent temperature increases on the Tibetan Plateau (TP) have triggered changes in the spring phenology of the local vegetation. However, remote sensing studies of the land surface phenology have reached conflicting interpretations about green-up patterns observed on the TP since the mid-1990s. We investigated this issue using field phenological observations from 1990 to 2006, for 11 dominant plants on the TP at the levels of species, families (Gramineae-grasses and Cyperaceae-sedges) and vegetation communities (alpine meadow and alpine steppe). We found a significant trend of earlier leaf-out dates for one species (Koeleria cristata). The leaf-out dates of both Gramineae and Cyperaceae had advanced (the latter significantly, starting an average of 9 days later per year than the former), but the correlation between them was significant. The leaf-out dates of both vegetation communities also advanced, but the pattern was only significant in the alpine meadow. This study provides the first field evidence of advancement in spring leaf phenology on the TP and suggests that the phenology of the alpine steppe can differ from that of the alpine meadow. These findings will be useful for understanding ecosystem responses to climate change and for grassland management on the TP. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  6. Dielectric and conductivity studies of Co-Cu mixed ferrite

    NASA Astrophysics Data System (ADS)

    Parveez, Asiya; Shekhawat, M. S.; Nayeem, Firdous; Mohd. Shariff, S.; Sinha, R. R.; Khader, S. Abdul

    2018-05-01

    Nanoparticles of Co-Cu mixed ferrite having the basic composition Co1-xCuxFe2O4(x=0, 0.2, 0.4, 0.6, 0.8 and 1.0) were synthesized using nitrate-citrate combustion method. Structural, dielectric and a.c conductivity of nanopowders, which are sintered at 900°C were studied. Powder X-ray diffraction studies confirmed phase and their nanocrystalline nature. The peaks observed in the XRD spectrum indicated single phase spinel cubic structure for the synthesized samples. Surface morphology of the samples has been investigated using High ResolutionScanning Electron Microscope. The dielectric constant (ɛ') and dielectric loss factor (ɛ″) of nanocrystalline Co-Cu mixed ferrites were investigated as a function of frequency and Cu+2 concentration at room temperature over the frequency range 100 Hz to 1 MHz using Hioki make LCR Hi-Tester 3250. Synthesized mixed ferrites exhibited usual dielectric dispersion, dependence of ɛ' and ɛ″ with the frequency of the alternating applied electric field is in accordance with the Maxwell-Wagner type interfacial polarization. The electrical conductivity (σac) deduced from the measured dielectric data has been thoroughly analyzed and found that the conduction mechanism in Co1-xCuxFe2O4 mixed nanoferrites are in conformity with the electron hopping model.

  7. Exposures of Sus scrofa to a TASER(®) conducted electrical weapon: no effects on 2-dimensional gel electrophoresis patterns of plasma proteins.

    PubMed

    Jauchem, James R; Cerna, Cesario Z; Lim, Tiffany Y; Seaman, Ronald L

    2014-12-01

    In an earlier study, we found significant changes in red-blood-cell, leukocyte, and platelet counts, and in red-blood-cell membrane proteins, following exposures of anesthetized pigs to a conducted electrical weapon. In the current study, we examined potential changes in plasma proteins [analyzed via two-dimensional gel electrophoresis (2-DGE)] following two 30 s exposures of anesthetized pigs (Sus scrofa) to a TASER (®) C2 conducted electrical weapon. Patterns of proteins, separated by 2-DGE, were consistent and reproducible between animals and between times of sampling. We determined that the blood plasma collection, handling, storage, and processing techniques we used are suitable for swine blood. There were no statistically significant changes in plasma proteins following the conducted-electrical-weapon exposures. Overall gel patterns of fibrinogen were similar to results of other studies of both pigs and humans (in control settings, not exposed to conducted electrical weapons). The lack of significant changes in plasma proteins may be added to the body of evidence regarding relative safety of TASER C2 device exposures.

  8. The Fischa-Dagnitz spring, Southern Vienna Basin: a multi tracer time series study re-assessing earlier conceptual assumptions.

    NASA Astrophysics Data System (ADS)

    Suckow, Axel; Gerber, Christoph; Kralik, Martin; Sültenfuss, Jürgen; Purtschert, Roland

    2013-04-01

    The gravel aquifer of the Southern Vienna Basin is a very important backup drinking water resource for the city of Vienna. A discharge location, the Fischa-Dagnitz spring in the Southern Vienna Basin, Austria, was re-investigated in 2011, five years after the gas exchange tracer test published in (Stolp et al., 2010), and sampled for stable isotopes 18O/2H, tritium, 3He, SF6 and 85Kr (Gerber et al., 2012). Additionally, new tritium time series data (Davis et al., 1967), previously not considered in Stolp et al. (2010), were included. These show a higher and earlier tritium peak of >300 TU in 1965 in the discharge of the Fischa-Dagnitz spring as compared to 221 TU in 1972 considered in Stolp et al. (2010). The new 3He, SF6 and 85Kr gas tracer data from 2011 confirm the earlier finding for 3He of Stolp et al. (2010) and indicate a more recent equilibration with the atmosphere than the water bound tracers 18O, 2H and tritium. A new modelling attempt using the Lumpy code (Suckow, 2012) confirmed the discrepancy between the tritium data and the gaseous tracers 3He, SF6 and 85Kr. No steady-state combination of local recharge (represented by an exponential model) and Schwarza river infiltration flowing through the gravel aquifer (represented by a parallel dispersion model) can equally well explain both the tritium time series and the gas tracer results. A revised conceptual model proposes that a pinching of the aquifer at unconformities in the gravel body or a fault zone known in the gravel body forces groundwater along the flow path closer to the surface and exposes it to the atmosphere. This would tend to reset the "dating" clock for the gaseous tracers 3He, SF6 and 85Kr, which can equilibrate quickly with the atmosphere, but not for tritium, which marks the transport behaviour of the water itself. These findings are of importance also for other multi-tracer assessments of groundwater movement in phreatic aquifer systems. References: Davis, G.H., Payne, B.R., Dincer, T

  9. First-Year Students' Expectations of Conduct and Consequence: A Case Study

    ERIC Educational Resources Information Center

    Crance Gutmann, Gina-Lyn

    2008-01-01

    Research on first-year students' expectations about college has explored areas of academic and social expectations, but not first-year college students' expectations about judicial conduct and consequence. The purpose of this study was to empirically explore two questions: what are first year students' expectations about campus conduct and…

  10. Comparison of bone-conducted vibration for eliciting ocular vestibular-evoked myogenic potentials: forehead versus mastoid tapping.

    PubMed

    Tseng, Chia-Chen; Wang, Shou-Jen; Young, Yi-Ho

    2012-02-01

    This study compared bone-conducted vibration (BCV) stimuli at forehead (Fz) and mastoid sites for eliciting ocular vestibular-evoked myogenic potentials (oVEMPs). Prospective study. University hospital. Twenty healthy subjects underwent oVEMP testing via BCV stimuli at Fz and mastoid sites. Another 50 patients with unilateral Meniere's disease also underwent oVEMP testing. All healthy subjects showed clear oVEMPs via BCV stimulation regardless of the tapping sites. The right oVEMPs stimulated by tapping at the right mastoid had earlier nI and pI latencies and a larger nI-pI amplitude compared with those stimulated by tapping at the Fz and left mastoid. Similar trends were also observed in left oVEMPs. However, the asymmetry ratio did not differ significantly between the ipsilateral mastoid and Fz sites. Clinically, tapping at the Fz revealed absent oVEMPs in 28% of Meniere's ears, which decreased to 16% when tapping at the ipsilesional (hydropic) mastoid site, exhibiting a significant difference. Tapping at the ipsilateral mastoid site elicits earlier oVEMP latencies and larger oVEMP amplitudes when compared with tapping at the Fz site. Thus, tapping at the Fz site is suggested to screen for the otolithic function, whereas tapping at the ipsilesional mastoid site is suitable for evaluating residual otolithic function.

  11. Objectifying Content Validity: Conducting a Content Validity Study in Social Work Research.

    ERIC Educational Resources Information Center

    Rubio, Doris McGartland; Berg-Weger, Marla; Tebb, Susan S.; Lee, E. Suzanne; Rauch, Shannon

    2003-01-01

    The purpose of this article is to demonstrate how to conduct a content validity study. Instructions on how to calculate a content validity index, factorial validity index, and an interrater reliability index and guide for interpreting these indices are included. Implications regarding the value of conducting a content validity study for…

  12. Polybenzimidazole block copolymers for fuel cell: synthesis and studies of block length effects on nanophase separation, mechanical properties, and proton conductivity of PEM.

    PubMed

    Maity, Sudhangshu; Jana, Tushar

    2014-05-14

    A series of meta-polybenzimidazole-block-para-polybenzimidazole (m-PBI-b-p-PBI), segmented block copolymers of PBI, were synthesized with various structural motifs and block lengths by condensing the diamine terminated meta-PBI (m-PBI-Am) and acid terminated para-PBI (p-PBI-Ac) oligomers. NMR studies and existence of two distinct glass transition temperatures (Tg), obtained from dynamical mechanical analysis (DMA) results, unequivocally confirmed the formation of block copolymer structure through the current polymerization methodology. Appropriate and careful selection of oligomers chain length enabled us to tailor the block length of block copolymers and also to make varieties of structural motifs. Increasingly distinct Tg peaks with higher block length of segmented block structure attributed the decrease in phase mixing between the meta-PBI and para-PBI blocks, which in turn resulted into nanophase segregated domains. The proton conductivities of proton exchange membrane (PEM) developed from phosphoric acid (PA) doped block copolymer membranes were found to be increasing substantially with increasing block length of copolymers even though PA loading of these membranes did not alter appreciably with varying block length. For example when molecular weight (Mn) of blocks were increased from 1000 to 5500 then the proton conductivities at 160 °C of resulting copolymers increased from 0.05 to 0.11 S/cm. Higher block length induced nanophase separation between the blocks by creating less morphological barrier within the block which facilitated the movement of the proton in the block and hence resulting higher proton conductivity of the PEM. The structural varieties also influenced the phase separation and proton conductivity. In comparison to meta-para random copolymers reported earlier, the current meta-para segmented block copolymers were found to be more suitable for PBI-based PEM.

  13. Latino community-based participatory research studies: a model for conducting bilingual translations.

    PubMed

    Sánchez-Johnsen, Lisa; Escamilla, Julia; Rodriguez, Erin M; Vega, Susan; Bolaños, Liliana

    2015-01-01

    Many behavioral health materials have not been translated into Spanish. Of those that are available in Spanish, some of them have not been translated correctly, many are only appropriate for a subgroup of Latinos, and/or multiple versions of the same materials exist. This article describes an innovative model of conducting bilingual English-Spanish translations as part of community-based participatory research studies and provides recommendations based on this model. In this article, the traditional process of conducting bilingual translations is reviewed, and an innovative model for conducting translations in collaboration with community partners is described. Finally, recommendations for conducting future health research studies with community partners are provided. Researchers, health care providers, educators, and community partners will benefit from learning about this innovative model that helps produce materials that are more culturally appropriate than those that are produced with the most commonly used method of conducting translations.

  14. Adult bacterial meningitis-a quality registry study: earlier treatment and favourable outcome if initial management by infectious diseases physicians.

    PubMed

    Grindborg, Ö; Naucler, P; Sjölin, J; Glimåker, M

    2015-06-01

    Acute bacterial meningitis (ABM) is challenging for the admitting physician because it is a rare but fulminant disease, usually presenting without typical symptoms, and rapid treatment is pivotal. The purpose of this study was to evaluate the effect of initial management by infectious diseases (ID) physicians vs. non-ID physicians. A total of 520 consecutive adults (>17 years old), 110 with initial ID management and 410 with non-ID management, registered in the Swedish quality registry for community-acquired ABM January 2008 to December 2013, were analysed retrospectively. Primary outcome was appropriate treatment with antibiotics and corticosteroids <1 hour from admission. Secondary analyses were mortality during hospital stay and persisting neurological and hearing deficits at follow-up after 2 to 6 months. Differences in diagnostic treatment sequences also were analysed. Appropriate treatment <1 hour from admission was achieved significantly more often (41%) by ID physicians vs. non-ID physicians (24%) with an odds ratio (OR) of 2.4 (95% confidence interval [CI]: 1.40 to 4.14; p < 0.01) adjusted for confounders. The door-to-antibiotic time was significantly shorter, and significantly more patients were administered corticosteroids together with the first doses of antibiotics in the ID group. A trend of decreased mortality (4.5% vs. 8.0%) and sequelae at follow-up (24% vs. 44%; adjusted OR 0.55: 95% CI 0.31 to 1.00; p 0.05) were observed in the ID group vs. the non-ID group. Antibiotics were started without prior neuroimaging more often in the ID group (86% vs. 57%; p < 0.001). Initial management at the emergency department by ID physicians is associated with earlier appropriate treatment, more appropriate diagnostic treatment sequences and favourable outcome. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  15. Colorectal cancer occurs earlier in those exposed to tobacco smoke: implications for screening

    PubMed Central

    Mahoney, Martin C.; Cummings, K. Michael; Michalek, Arthur M.; Reid, Mary E.; Moysich, Kirsten B.; Hyland, Andrew

    2011-01-01

    Background Colorectal cancer (CRC) is the third most common cancer in the USA. While various lifestyle factors have been shown to alter the risk for colorectal cancer, recommendations for the early detection of CRC are based only on age and family history. Methods This case-only study examined the age at diagnosis of colorectal cancer in subjects exposed to tobacco smoke. Subjects included all patients who attended RPCI between 1957 and 1997, diagnosed with colorectal cancer, and completed an epidemiologic questionnaire. Adjusted linear regression models were calculated for the various smoking exposures. Results Of the 3,540 cases of colorectal cancer, current smokers demonstrated the youngest age of CRC onset (never: 64.2 vs. current: 57.4, P < 0.001) compared to never smokers, followed by recent former smokers. Among never smokers, individuals with past second-hand smoke exposure were diagnosed at a significantly younger age compared to the unexposed. Conclusion This study found that individuals with heavy, long-term tobacco smoke exposure were significantly younger at the time of CRC diagnosis compared to lifelong never smokers. The implication of this finding is that screening for colorectal cancer, which is recommended to begin at age 50 years for persons at average risk should be initiated 5–10 years earlier for persons with a significant lifetime history of exposure to tobacco smoke. PMID:18264728

  16. Combined circulating tumor DNA and protein biomarker-based liquid biopsy for the earlier detection of pancreatic cancers.

    PubMed

    Cohen, Joshua D; Javed, Ammar A; Thoburn, Christopher; Wong, Fay; Tie, Jeanne; Gibbs, Peter; Schmidt, C Max; Yip-Schneider, Michele T; Allen, Peter J; Schattner, Mark; Brand, Randall E; Singhi, Aatur D; Petersen, Gloria M; Hong, Seung-Mo; Kim, Song Cheol; Falconi, Massimo; Doglioni, Claudio; Weiss, Matthew J; Ahuja, Nita; He, Jin; Makary, Martin A; Maitra, Anirban; Hanash, Samir M; Dal Molin, Marco; Wang, Yuxuan; Li, Lu; Ptak, Janine; Dobbyn, Lisa; Schaefer, Joy; Silliman, Natalie; Popoli, Maria; Goggins, Michael G; Hruban, Ralph H; Wolfgang, Christopher L; Klein, Alison P; Tomasetti, Cristian; Papadopoulos, Nickolas; Kinzler, Kenneth W; Vogelstein, Bert; Lennon, Anne Marie

    2017-09-19

    The earlier diagnosis of cancer is one of the keys to reducing cancer deaths in the future. Here we describe our efforts to develop a noninvasive blood test for the detection of pancreatic ductal adenocarcinoma. We combined blood tests for KRAS gene mutations with carefully thresholded protein biomarkers to determine whether the combination of these markers was superior to any single marker. The cohort tested included 221 patients with resectable pancreatic ductal adenocarcinomas and 182 control patients without known cancer. KRAS mutations were detected in the plasma of 66 patients (30%), and every mutation found in the plasma was identical to that subsequently found in the patient's primary tumor (100% concordance). The use of KRAS in conjunction with four thresholded protein biomarkers increased the sensitivity to 64%. Only one of the 182 plasma samples from the control cohort was positive for any of the DNA or protein biomarkers (99.5% specificity). This combinatorial approach may prove useful for the earlier detection of many cancer types.

  17. Experimental and modeling study of forest fire effect on soil thermal conductivity

    Treesearch

    Kathleen M. Smits; Elizabeth Kirby; William J. Massman; Scott Baggett

    2016-01-01

    An understanding of soil thermal conductivity after a wildfire or controlled burn is important to land management and post-fire recovery efforts. Although soil thermal conductivity has been well studied for non-fire heated soils, comprehensive data that evaluate the long-term effect of extreme heating from a fire on the soil thermal conductivity are limited....

  18. AC and DC conductivity study on Ca substituted bismuth ferrite

    NASA Astrophysics Data System (ADS)

    Pandey, Rabichandra; Pradhan, Lagen Kumar; Kumar, Sunil; Kar, Manoranjan

    2018-05-01

    Bi0.95Ca0.05FeO3 multiferroic compound was synthesized by the citric acid modified sol-gel method. Crystal structure of Bi0.95Ca0.05FeO3 is studied by the X-ray diffraction (XRD) technique. The ac impedance analysis of the compound has been carried out in a wide range of frequency (100 Hz - 1MHz) as well as temperature (40-2500C). Frequency variation of dielectric constant at different temperatures can be understood by the modified Debye formula. The activation energy was found to be 0.48eV, which was obtained by employing Arrhenius equation. The AC conductivity of the sample follows the Johnscher's power law which indicates the presence of hopping type conduction in localized charged states. To understand the conduction mechanism with localized charge states, the DC resistivity data were analyzed by Mott's variable range hopping (VRH) model. The activation energy calculated from Debye relaxation time, AC conductivity and DC resistivity are comparable to each other.

  19. Low protein content of drainage fluid is a good predictor for earlier chest tube removal after lobectomy.

    PubMed

    Olgac, Guven; Cosgun, Tugba; Vayvada, Mustafa; Ozdemir, Atilla; Kutlu, Cemal Asim

    2014-10-01

    Owing to the great absorption capability of the pleura for transudates, the protein content of draining pleural fluid may be considered as a more adequate determinant than its daily draining amount in the decision-making for earlier chest tube removal. In an a priori pilot study, we observed that the initially draining protein-rich exudate converts to a transudate quickly in most patients after lobectomies. Thus, chest tubes draining high-volume but low-protein fluids can safely be removed earlier in the absence of an air leak. This randomized study aims to investigate the validity and clinical applicability of this hypothesis as well as its influence on the timing for chest tube removal and earlier discharge after lobectomy. Seventy-two consecutive patients undergoing straightforward lobectomy were randomized into two groups. Patients with conditions affecting postoperative drainage and with persisting air leaks beyond the third postoperative day were excluded. Drains were removed if the pleural fluid to blood protein ratio (PrRPl/B) was ≤0.5, regardless of its daily draining amount in the study arm (Group S; n = 38), and patients in the control arm (Group C; n = 34) had their tubes removed if daily drainage was ≤250 ml regardless of its protein content. Patients were discharged home immediately or the following morning after removal of the last drain. All cases were followed up regarding the development of symptomatic pleural effusions and hospital readmissions for a redrainage procedure. Demographic and clinical characteristics as well as the pattern of decrease in PrRPl/B were the same between groups. The mean PrRPl/B was 0.65 and 0.67 (95% CI = 0.60-0.69 and 0.62-0.72) on the first postoperative day, and it remarkably dropped down to 0.39 and 0.33 (95% CI = 0.33-0.45 and 0.27-0.39) on the second day in Groups S and C, respectively, and remained below 0.5 on the third day (repeated-measures of ANOVA design, post hoc 'within-group' comparison of the first

  20. Thermal conductivity studies of CdZnTe with varying Te excess

    DOE PAGES

    Jackson, Maxx; Bennett, Brittany; Giltnane, Dustin; ...

    2016-08-28

    Cadmium Zine Telluride (CZT) has been extensively studied as a room temperature semiconductor gamma radiation detector. CZT continues to show promise as a bulk and pixelated gamma spectrometer with less than one percent energy resolution; however the fabrication costs are high. Improved yields of high quality, large CZT spectroscopy grade crystals must be achieved. CZT is grown by the Traveling Heater Method (THM) with a Te overpressure to account for vaporization losses. This procedure creates Te rich zones. During growth, boules will often cleave limiting the number of harvestable crystals. As a result, crystal growth parameter optimization was evaluated bymore » modeling the heat flow within the system. Interestingly, Cadmium Telluride (CdTe) is used as a thermal conductivity surrogate in the absence of a thorough study of the CZT thermal properties. The current study has measured the thermal conductivity of CZT pressed powders with varying Te concentrations from 50-100% over 25-800°C to understand the variation in this parameter from CdTe. Cd0.9Zn0.1Te1.0 is the base CZT (designated 50%). CZT exhibits a thermal conductivity of nearly 1 W/mK, an order of magnitude greater than CdTe. Lastly, the thermal conductivity decreased with increasing Te concentration.« less

  1. Thermal conductivity studies of CdZnTe with varying Te excess

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jackson, Maxx; Bennett, Brittany; Giltnane, Dustin

    Cadmium Zine Telluride (CZT) has been extensively studied as a room temperature semiconductor gamma radiation detector. CZT continues to show promise as a bulk and pixelated gamma spectrometer with less than one percent energy resolution; however the fabrication costs are high. Improved yields of high quality, large CZT spectroscopy grade crystals must be achieved. CZT is grown by the Traveling Heater Method (THM) with a Te overpressure to account for vaporization losses. This procedure creates Te rich zones. During growth, boules will often cleave limiting the number of harvestable crystals. As a result, crystal growth parameter optimization was evaluated bymore » modeling the heat flow within the system. Interestingly, Cadmium Telluride (CdTe) is used as a thermal conductivity surrogate in the absence of a thorough study of the CZT thermal properties. The current study has measured the thermal conductivity of CZT pressed powders with varying Te concentrations from 50-100% over 25-800°C to understand the variation in this parameter from CdTe. Cd0.9Zn0.1Te1.0 is the base CZT (designated 50%). CZT exhibits a thermal conductivity of nearly 1 W/mK, an order of magnitude greater than CdTe. Lastly, the thermal conductivity decreased with increasing Te concentration.« less

  2. Probability distributions of hydraulic conductivity for the hydrogeologic units of the Death Valley regional ground-water flow system, Nevada and California

    USGS Publications Warehouse

    Belcher, Wayne R.; Sweetkind, Donald S.; Elliott, Peggy E.

    2002-01-01

    The use of geologic information such as lithology and rock properties is important to constrain conceptual and numerical hydrogeologic models. This geologic information is difficult to apply explicitly to numerical modeling and analyses because it tends to be qualitative rather than quantitative. This study uses a compilation of hydraulic-conductivity measurements to derive estimates of the probability distributions for several hydrogeologic units within the Death Valley regional ground-water flow system, a geologically and hydrologically complex region underlain by basin-fill sediments, volcanic, intrusive, sedimentary, and metamorphic rocks. Probability distributions of hydraulic conductivity for general rock types have been studied previously; however, this study provides more detailed definition of hydrogeologic units based on lithostratigraphy, lithology, alteration, and fracturing and compares the probability distributions to the aquifer test data. Results suggest that these probability distributions can be used for studies involving, for example, numerical flow modeling, recharge, evapotranspiration, and rainfall runoff. These probability distributions can be used for such studies involving the hydrogeologic units in the region, as well as for similar rock types elsewhere. Within the study area, fracturing appears to have the greatest influence on the hydraulic conductivity of carbonate bedrock hydrogeologic units. Similar to earlier studies, we find that alteration and welding in the Tertiary volcanic rocks greatly influence hydraulic conductivity. As alteration increases, hydraulic conductivity tends to decrease. Increasing degrees of welding appears to increase hydraulic conductivity because welding increases the brittleness of the volcanic rocks, thus increasing the amount of fracturing.

  3. Screening for Colorectal Cancer in African Americans: Determinants and Rationale for an Earlier Age to Commence Screening

    PubMed Central

    Carethers, John M.

    2014-01-01

    Colorectal cancer (CRC) screening is a highly cost-effective approach to reduce morbidity and mortality of patients, as well as reduce the prevalence of CRC in populations. Current recommendations for CRC screening for the asymptomatic general population begin at age 50 years, an age after which ~95% of cancers occur. Determinants that modify the timing and frequency for screening include a personal or family history of adenomatous polyps or CRC, the age of onset of these colonic lesions, and the presence or potential for a patient to harbor a higher-risk syndrome such as inflammatory bowel disease (IBD), familial adenomatous polyposis (FAP), or Lynch syndrome.. Although race, like family history, is a heritable factor, it has not engendered inclusion in the same broad systematic screening recommendations despite multiple studies demonstrating a disparity in the incidence and mortality from CRC, and the potential for targeted screening to reduce the disparity. In particular, African Americans, when compared to Caucasians, (a) have lower CRC screening utilization rates, (b) have an earlier presentation of CRC (0-8 years younger than Caucasians) and, more often have aggressive biological features more prone to metastasis, (c) have a higher CRC prevalence at all ages and a higher proportion of CRCs before 50 years of age (~11% vs 5% in Caucasians), (d) are less likely to know or transmit personal or family history of adenomas or CRC that might change their screening to an earlier age, (e) present with 7-15% excess right-sided CRCs that are not microsatellite unstable, (f) show higher frequencies of high-risk adenomas at every decile of age, and an excess of high-risk proximal adenomas that mirror the excess of proximal CRCs, (g) have cancers that demonstrate lower proportions of good prognostic biomarkers such as MSI and higher proportions of bad prognosticators such as EMAST, (h) may possess gut microbiota more conducive to initiating and/or propagating colonic

  4. Phrenic nerve conduction studies: normative data and technical aspects.

    PubMed

    Maranhão, Analucia Abreu; Carvalho, Sonia Regina da Silva; Caetano, Marcelo Ribeiro; Alamy, Alexandre Hofke; Peixoto, Eduardo Mesquita; Filgueiras, Pedro Del Esporte Peçanha

    2017-12-01

    The aim of the present study was to define normative data of phrenic nerve conduction parameters of a healthy population. Phrenic nerve conduction studies were performed in 27 healthy volunteers. The normative limits for expiratory phrenic nerve compound muscle action potential were: amplitude (0.47 mv - 0.83 mv), latency (5.74 ms - 7.10 ms), area (6.20 ms/mv - 7.20 ms/mv) and duration (18.30 ms - 20.96 ms). Inspiratory normative limits were: amplitude (0.67 mv - 1.11 mv), latency (5.90 ms - 6.34 ms), area (5.62 ms/mv - 6.72 ms/mv) and duration (13.77 ms - 15.37 ms). The best point of phrenic nerve stimulus in the neck varies among individuals between the medial and lateral border of the clavicular head of the sternocleidomastoid muscle and stimulation of both sites, then choosing the best phrenic nerve response, seems to be the appropriate procedure.

  5. Phononic thermal conductivity in silicene: the role of vacancy defects and boundary scattering

    NASA Astrophysics Data System (ADS)

    Barati, M.; Vazifehshenas, T.; Salavati-fard, T.; Farmanbar, M.

    2018-04-01

    We calculate the thermal conductivity of free-standing silicene using the phonon Boltzmann transport equation within the relaxation time approximation. In this calculation, we investigate the effects of sample size and different scattering mechanisms such as phonon–phonon, phonon-boundary, phonon-isotope and phonon-vacancy defect. We obtain some similar results to earlier works using a different model and provide a more detailed analysis of the phonon conduction behavior and various mode contributions. We show that the dominant contribution to the thermal conductivity of silicene, which originates from the in-plane acoustic branches, is about 70% at room temperature and this contribution becomes larger by considering vacancy defects. Our results indicate that while the thermal conductivity of silicene is significantly suppressed by the vacancy defects, the effect of isotopes on the phononic transport is small. Our calculations demonstrate that by removing only one of every 400 silicon atoms, a substantial reduction of about 58% in thermal conductivity is achieved. Furthermore, we find that the phonon-boundary scattering is important in defectless and small-size silicene samples, especially at low temperatures.

  6. Mössbauer study of conductive oxide glass

    NASA Astrophysics Data System (ADS)

    Matsuda, Koken; Kubuki, Shiro; Nishida, Tetsuaki

    2014-10-01

    Heat treatment of barium iron vanadate glass, BaO - Fe2O3- V2O5, at temperatures higher than crystallization temperature causes a marked decrease in resistivity (ρ) from several MΩcm to several Ωcm. 57Fe Mössbauer spectrum of heat-treated vanadate glass shows a marked decrease in quadrupole splitting (Δ) of FeIII, reflecting a structural relaxation, i.e., an increased symmetry of "distorted" FeO4 and VO4 tetrahedra which are connected to each other by sharing corner oxygen atoms. Structural relaxation of 3D-network of vanadate glass accompanies a decrease in the activation energy for the conduction, reflecting a decreased energy gap between the donor level and conduction band. A marked increase in the conductivity was observed in CuO- or Cu2O -containing barium iron vanadate glass after heat treatment at 450 °C for 30 min or more. "n-type semiconductor model combined with small polaron hopping theory" was proposed in order to explain the high conductivity.

  7. A Hepatocellular Carcinoma Case in a Patient Who had Immunity to Hepatitis B Virus Earlier.

    PubMed

    Ates, Ihsan; Kaplan, Mustafa; Demirci, Selim; Altiparmak, Emin

    2016-01-01

    Hepatocellular carcinoma (HCC) is the most common malignant tumor of the liver. Hepatitis B virus infection is one of the most important etilogical factors of HCC. In this case report, a patient with HCC previously infected and having ongoing immunity against hepatitis B virus will be discussed. Ates I, Kaplan M, Demirci S, Altiparmak E. A Hepatocellular Carcinoma Case in a Patient Who had Immunity to Hepatitis B Virus Earlier. Euroasian J Hepato-Gastroenterol 2016;6(1):82-83.

  8. Selection for Earlier Flowering Crop Associated with Climatic Variations in the Sahel

    PubMed Central

    Vigouroux, Yves; Mariac, Cédric; De Mita, Stéphane; Pham, Jean-Louis; Gérard, Bruno; Kapran, Issoufou; Sagnard, Fabrice; Deu, Monique; Chantereau, Jacques; Ali, Abdou; Ndjeunga, Jupiter; Luong, Viviane; Thuillet, Anne-Céline; Saïdou, Abdoul-Aziz; Bezançon, Gilles

    2011-01-01

    Climate changes will have an impact on food production and will require costly adaptive responses. Adapting to a changing environment will be particularly challenging in sub-Saharan Africa where climate change is expected to have a major impact. However, one important phenomenon that is often overlooked and is poorly documented is the ability of agro-systems to rapidly adapt to environmental variations. Such an adaptation could proceed by the adoption of new varieties or by the adaptation of varieties to a changing environment. In this study, we analyzed these two processes in one of the driest agro-ecosystems in Africa, the Sahel. We performed a detailed study in Niger where pearl millet is the main crop and covers 65% of the cultivated area. To assess how the agro-system is responding to recent recurrent drought, we analyzed samples of pearl millet landraces collected in the same villages in 1976 and 2003 throughout the entire cultivated area of Niger. We studied phenological and morphological differences in the 1976 and 2003 collections by comparing them over three cropping seasons in a common garden experiment. We found no major changes in the main cultivated varieties or in their genetic diversity. However, we observed a significant shift in adaptive traits. Compared to the 1976 samples, samples collected in 2003 displayed a shorter lifecycle, and a reduction in plant and spike size. We also found that an early flowering allele at the PHYC locus increased in frequency between 1976 and 2003. The increase exceeded the effect of drift and sampling, suggesting a direct effect of selection for earliness on this gene. We conclude that recurrent drought can lead to selection for earlier flowering in a major Sahelian crop. Surprisingly, these results suggest that diffusion of crop varieties is not the main driver of short term adaptation to climatic variation. PMID:21573243

  9. Quantifying the economic value and quality of life impact of earlier influenza vaccination.

    PubMed

    Lee, Bruce Y; Bartsch, Sarah M; Brown, Shawn T; Cooley, Philip; Wheaton, William D; Zimmerman, Richard K

    2015-03-01

    Influenza vaccination is administered throughout the influenza disease season, even as late as March. Given such timing, what is the value of vaccinating the population earlier than currently being practiced? We used real data on when individuals were vaccinated in Allegheny County, Pennsylvania, and the following 2 models to determine the value of vaccinating individuals earlier (by the end of September, October, and November): Framework for Reconstructing Epidemiological Dynamics (FRED), an agent-based model (ABM), and FluEcon, our influenza economic model that translates cases from the ABM to outcomes and costs [health care and lost productivity costs and quality-adjusted life-years (QALYs)]. We varied the reproductive number (R0) from 1.2 to 1.6. Applying the current timing of vaccinations averted 223,761 influenza cases, $16.3 million in direct health care costs, $50.0 million in productivity losses, and 804 in QALYs, compared with no vaccination (February peak, R0 1.2). When the population does not have preexisting immunity and the influenza season peaks in February (R0 1.2-1.6), moving individuals who currently received the vaccine after September to the end of September could avert an additional 9634-17,794 influenza cases, $0.6-$1.4 million in direct costs, $2.1-$4.0 million in productivity losses, and 35-64 QALYs. Moving the vaccination of just children to September (R0 1.2-1.6) averted 11,366-1660 influenza cases, $0.6-$0.03 million in direct costs, $2.3-$0.2 million in productivity losses, and 42-8 QALYs. Moving the season peak to December increased these benefits, whereas increasing preexisting immunity reduced these benefits. Even though many people are vaccinated well after September/October, they likely are still vaccinated early enough to provide substantial cost-savings.

  10. Electromagnetic studies in the Fennoscandian Shield—electrical conductivity of Precambrian crust

    NASA Astrophysics Data System (ADS)

    Korja, T.; Hjelt, S.-E.

    1993-12-01

    Electromagnetic (EM) investigations of the 1980s in the Fennoscandian (Baltic) Shield produced an unique and unified EM data set. Studies include regional investigations by the magnetovariational (MV) method with large lateral sampling distance, investigations of anomalous conductivity structures by magnetotelluric (MT) soundings and other (EM) and electrical methods (audio MT soundings, d.c. dipole-dipole and VLF resistivity profilings) with shorter sampling distance, and studies of the near-surface conductivity by airborne EM surveys. The variety of methods provide an ability to map efficiently crustal conductivity structures from a regional scale of hundreds of kilometres down to local details of some metres in the anomalous structures. The Precambrian of the Fennoscandian Shield is characterized by roughly NW-SE-directed elongated belts of conductors which separate more resistive crustal blocks. The latter serve as transparent windows through which to probe deep electrical structure and belts of conductors as tectonic markers of ancient orogenic zones including (1) the Kittilä-Vetrenny Poyas conductor, (2) the Lapland Granulite Belt and Inari-Pechenga-Imandra-Varzuga conductors, (3) the Archaean-Proterozoic boundary conductor and (4) the Southern Finland Conductor. The conductive belts—orogenic conductors—indicate places where crustal masses collided and were finally sealed together. Enhanced conductivity in the orogenic conductors is caused primarily by an electronic conducting mechanism in graphite- and sulphide-bearing metasedimentary rocks. Estimations of the lower-crustal conductivity indicate a laterally heterogeneous lower crust in the Fennoscandian Shield. Archaean lower crust seems to be in general more resistive than the Early Proterozoic lower crust of the Karelian and Svecofennian Domains. The lower crust in the southwestern part of the Svecofennian Domain and in the Sveconorwegian Domain seems to be more resistive than in the central part of

  11. The Earlier the Better? Taking the AP® in 10th Grade. Research Report No. 2012-10

    ERIC Educational Resources Information Center

    Rodriguez, Awilda; McKillip, Mary E. M.; Niu, Sunny X.

    2013-01-01

    In this report, the authors examine the impact of scoring a 1 or 2 on an AP® Exam in 10th grade on later AP Exam participation and performance. As access to AP courses increases within and across schools, a growing number of students are taking AP courses and exams in the earlier grades of high school. Using a matched sample of AP and no-AP…

  12. Moderately premature infants at Kaiser Permanente Medical Care Program in California are discharged home earlier than their peers in Massachusetts and the United Kingdom

    PubMed Central

    Profit, J; Zupancic, J A F; McCormick, M C; Richardson, D K; Escobar, G J; Tucker, J; Tarnow‐Mordi, W; Parry, G

    2006-01-01

    Objective To compare gestational age at discharge between infants born at 30–34+6 weeks gestational age who were admitted to neonatal intensive care units (NICUs) in California, Massachusetts, and the United Kingdom. Design Prospective observational cohort study. Setting Fifty four United Kingdom, five California, and five Massachusetts NICUs. Subjects A total of 4359 infants who survived to discharge home after admission to an NICU. Main outcome measures Gestational age at discharge home. Results The mean (SD) postmenstrual age at discharge of the infants in California, Massachusetts, and the United Kingdom were 35.9 (1.3), 36.3 (1.3), and 36.3 (1.9) weeks respectively (p  =  0.001). Compared with the United Kingdom, adjusted discharge of infants occurred 3.9 (95% confidence interval (CI) 1.4 to 6.5) days earlier in California, and 0.9 (95% CI −1.2 to 3.0) days earlier in Massachusetts. Conclusions Infants of 30–34+6 weeks gestation at birth admitted and cared for in hospitals in California have a shorter length of stay than those in the United Kingdom. Certain characteristics of the integrated healthcare approach pursued by the health maintenance organisation of the NICUs in California may foster earlier discharge. The California system may provide opportunities for identifying practices for reducing the length of stay of moderately premature infants. PMID:16449257

  13. Association between severe dorsolateral prefrontal dysfunction during random number generation and earlier onset in schizophrenia.

    PubMed

    Koike, Shinsuke; Takizawa, Ryu; Nishimura, Yukika; Marumo, Kohei; Kinou, Masaru; Kawakubo, Yuki; Rogers, Mark A; Kasai, Kiyoto

    2011-08-01

    Schizophrenia involves impairment in attention, working memory and executive processes associated with prefrontal cortical function, an essential contributor of social functioning. Age at onset is a major factor for predicting social outcome in schizophrenia. In clinical settings, we need an objective assessment tool for evaluating prefrontal function and social outcome. Participants included 22 right-handed patients with schizophrenia and 40 gender- and age-matched healthy controls. We used a 52-channel near-infrared spectroscopy (NIRS) instrument to measure oxygenated haemoglobin ([oxy-Hb]) changes over the prefrontal cortex during a random number generation (RNG) task. In healthy controls, we found significant [oxy-Hb] increase in the bilateral dorsolateral (DLPFC; BA9 and BA46) and ventrolateral prefrontal cortex (VLPFC; BA44, 45 and 47). The patients with schizophrenia showed significantly smaller activation than the healthy controls in the same approximate regions. In the patient group, a smaller [oxy-Hb] increase in the right DLPFC region (BA9) was significantly correlated with earlier age at onset. NIRS can detect prefrontal cortical dysfunction associated with an executive task, which was coupled with earlier age at onset in schizophrenia. Multichannel NIRS, a non-invasive and user-friendly instrument, may be useful in evaluating cognitive function and social outcome in clinical settings in psychiatry. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  14. Ab initio computational study on the lattice thermal conductivity of Zintl clathrates [Si19P4] Cl4 and Na4[Al4Si19

    NASA Astrophysics Data System (ADS)

    Härkönen, Ville J.; Karttunen, Antti J.

    2016-08-01

    The lattice thermal conductivity of silicon clathrate framework Si23 and two Zintl clathrates, [Si19P4] Cl4 and Na4[Al4Si19] , is investigated by using an iterative solution of the linearized Boltzmann transport equation in conjunction with ab initio lattice dynamical techniques. At 300 K, the lattice thermal conductivities for Si23, [Si19P4] Cl4 , and Na4[Al4Si19] were found to be 43 W/(m K), 25 W/(m K), and 2 W/(m K), respectively. In the case of Na4[Al4Si19] , the order-of-magnitude reduction in the lattice thermal conductivity was found to be mostly due to relaxation times and group velocities differing from Si23 and [Si19P4] Cl4 . The difference in the relaxation times and group velocities arises primarily due to the phonon spectrum at low frequencies, resulting eventually from the differences in the second-order interatomic force constants (IFCs). The obtained third-order IFCs were rather similar for all materials considered here. The present findings are similar to those obtained earlier for some skutterudites. The predicted lattice thermal conductivity of Na4[Al4Si19] is in line with the experimentally measured thermal conductivity of recently synthesized type-I Zintl clathrate Na8[Al8Si38] (polycrystalline samples).

  15. Considerations for conducting epidemiologic case-control studies of cancer in developing countries.

    PubMed

    Brinton, L A; Herrero, R; Brenes, M; Montalván, P; de la Guardia, M E; Avila, A; Domínguez, I L; Basurto, E; Reeves, W C

    1991-01-01

    The challenges involved in conducting epidemiologic studies of cancer in developing countries can be and often are unique. This article reports on our experience in performing a case-control study of invasive cervical cancer in four Latin American countries (Columbia, Costa Rica, Mexico, and Panama), the summary medical results of which have been published in a previous issue of this journal (1). The study involved a number of principal activities--mainly selecting, conducting interviews with, and obtaining appropriate biologic specimens from 759 cervical cancer patients, 1,467 matched female controls, and 689 male sex partners of monogamous female subjects. This presentation provides an overview of the planning and methods used to select the subjects, conduct the survey work, and obtain complete and effectively unbiased data. It also points out some of the important advantages and disadvantages of working in developing areas similar to those serving as locales for this study.

  16. Combined circulating tumor DNA and protein biomarker-based liquid biopsy for the earlier detection of pancreatic cancers

    PubMed Central

    Cohen, Joshua D.; Javed, Ammar A.; Thoburn, Christopher; Wong, Fay; Tie, Jeanne; Gibbs, Peter; Schmidt, C. Max; Yip-Schneider, Michele T.; Allen, Peter J.; Schattner, Mark; Brand, Randall E.; Singhi, Aatur D.; Petersen, Gloria M.; Hong, Seung-Mo; Kim, Song Cheol; Falconi, Massimo; Doglioni, Claudio; Weiss, Matthew J.; Ahuja, Nita; He, Jin; Makary, Martin A.; Maitra, Anirban; Hanash, Samir M.; Dal Molin, Marco; Wang, Yuxuan; Li, Lu; Ptak, Janine; Dobbyn, Lisa; Schaefer, Joy; Silliman, Natalie; Popoli, Maria; Goggins, Michael G.; Hruban, Ralph H.; Wolfgang, Christopher L.; Klein, Alison P.; Tomasetti, Cristian; Papadopoulos, Nickolas; Kinzler, Kenneth W.; Vogelstein, Bert; Lennon, Anne Marie

    2017-01-01

    The earlier diagnosis of cancer is one of the keys to reducing cancer deaths in the future. Here we describe our efforts to develop a noninvasive blood test for the detection of pancreatic ductal adenocarcinoma. We combined blood tests for KRAS gene mutations with carefully thresholded protein biomarkers to determine whether the combination of these markers was superior to any single marker. The cohort tested included 221 patients with resectable pancreatic ductal adenocarcinomas and 182 control patients without known cancer. KRAS mutations were detected in the plasma of 66 patients (30%), and every mutation found in the plasma was identical to that subsequently found in the patient’s primary tumor (100% concordance). The use of KRAS in conjunction with four thresholded protein biomarkers increased the sensitivity to 64%. Only one of the 182 plasma samples from the control cohort was positive for any of the DNA or protein biomarkers (99.5% specificity). This combinatorial approach may prove useful for the earlier detection of many cancer types. PMID:28874546

  17. Conductivity studies of PEG based polymer electrolyte for applications as electrolyte in ion batteries

    NASA Astrophysics Data System (ADS)

    Patil, Ravikumar V.; Praveen, D.; Damle, R.

    2018-05-01

    Development of lithium ion batteries employing solid polymer electrolytes as electrolyte material has led to efficient energy storage and usage in many portable devices. However, due to a few drawbacks like lower ionic conductivity of solid polymer electrolytes (SPEs), studies on SPEs for improvement in conductivity still have a good scope. In the present paper, we report the conductivity studies of a new SPE with low molecular weight poly ethylene glycol (PEG) as host polymer in which a salt with larger anion Lithium trifluro methane sulphonate (LTMS). XRD studies have revealed that the salt completely dissociates in the polymer giving a good stable electrolyte at lower salt concentration. Conductivity of the SPEs has been studied as a function of temperature and we reiterate that the conductivity is a thermally activated process and follows Arrhenius type behavior.

  18. Thermal and electrical contact conductance studies

    NASA Technical Reports Server (NTRS)

    Vansciver, S. W.; Nilles, M.

    1985-01-01

    Prediction of electrical and thermal contact resistance for pressed, nominally flat contacts is complicated by the large number of variables which influence contact formation. This is reflected in experimental results as a wide variation in contact resistances, spanning up to six orders of magnitude. A series of experiments were performed to observe the effects of oxidation and surface roughness on contact resistance. Electrical contact resistance and thermal contact conductance from 4 to 290 K on OFHC Cu contacts are reported. Electrical contact resistance was measured with a 4-wire DC technique. Thermal contact conductance was determined by steady-state longitudinal heat flow. Corrections for the bulk contribution ot the overall measured resistance were made, with the remaining resistance due solely to the presence of the contact.

  19. Earlier Visual N1 Latencies in Expert Video-Game Players: A Temporal Basis of Enhanced Visuospatial Performance?

    PubMed Central

    Latham, Andrew J.; Patston, Lucy L. M.; Westermann, Christine; Kirk, Ian J.; Tippett, Lynette J.

    2013-01-01

    Increasing behavioural evidence suggests that expert video game players (VGPs) show enhanced visual attention and visuospatial abilities, but what underlies these enhancements remains unclear. We administered the Poffenberger paradigm with concurrent electroencephalogram (EEG) recording to assess occipital N1 latencies and interhemispheric transfer time (IHTT) in expert VGPs. Participants comprised 15 right-handed male expert VGPs and 16 non-VGP controls matched for age, handedness, IQ and years of education. Expert VGPs began playing before age 10, had a minimum 8 years experience, and maintained playtime of at least 20 hours per week over the last 6 months. Non-VGPs had little-to-no game play experience (maximum 1.5 years). Participants responded to checkerboard stimuli presented to the left and right visual fields while 128-channel EEG was recorded. Expert VGPs responded significantly more quickly than non-VGPs. Expert VGPs also had significantly earlier occipital N1s in direct visual pathways (the hemisphere contralateral to the visual field in which the stimulus was presented). IHTT was calculated by comparing the latencies of occipital N1 components between hemispheres. No significant between-group differences in electrophysiological estimates of IHTT were found. Shorter N1 latencies may enable expert VGPs to discriminate attended visual stimuli significantly earlier than non-VGPs and contribute to faster responding in visual tasks. As successful video-game play requires precise, time pressured, bimanual motor movements in response to complex visual stimuli, which in this sample began during early childhood, these differences may reflect the experience and training involved during the development of video-game expertise, but training studies are needed to test this prediction. PMID:24058667

  20. Earlier visual N1 latencies in expert video-game players: a temporal basis of enhanced visuospatial performance?

    PubMed

    Latham, Andrew J; Patston, Lucy L M; Westermann, Christine; Kirk, Ian J; Tippett, Lynette J

    2013-01-01

    Increasing behavioural evidence suggests that expert video game players (VGPs) show enhanced visual attention and visuospatial abilities, but what underlies these enhancements remains unclear. We administered the Poffenberger paradigm with concurrent electroencephalogram (EEG) recording to assess occipital N1 latencies and interhemispheric transfer time (IHTT) in expert VGPs. Participants comprised 15 right-handed male expert VGPs and 16 non-VGP controls matched for age, handedness, IQ and years of education. Expert VGPs began playing before age 10, had a minimum 8 years experience, and maintained playtime of at least 20 hours per week over the last 6 months. Non-VGPs had little-to-no game play experience (maximum 1.5 years). Participants responded to checkerboard stimuli presented to the left and right visual fields while 128-channel EEG was recorded. Expert VGPs responded significantly more quickly than non-VGPs. Expert VGPs also had significantly earlier occipital N1s in direct visual pathways (the hemisphere contralateral to the visual field in which the stimulus was presented). IHTT was calculated by comparing the latencies of occipital N1 components between hemispheres. No significant between-group differences in electrophysiological estimates of IHTT were found. Shorter N1 latencies may enable expert VGPs to discriminate attended visual stimuli significantly earlier than non-VGPs and contribute to faster responding in visual tasks. As successful video-game play requires precise, time pressured, bimanual motor movements in response to complex visual stimuli, which in this sample began during early childhood, these differences may reflect the experience and training involved during the development of video-game expertise, but training studies are needed to test this prediction.

  1. Outcomes of childhood conduct problem trajectories in early adulthood: findings from the ALSPAC study.

    PubMed

    Kretschmer, Tina; Hickman, Matthew; Doerner, Rita; Emond, Alan; Lewis, Glyn; Macleod, John; Maughan, Barbara; Munafò, Marcus R; Heron, Jon

    2014-07-01

    Although conduct problems in childhood are stably associated with problem outcomes, not every child who presents with conduct problems is at risk. This study extends previous studies by testing whether childhood conduct problem trajectories are predictive of a wide range of other health and behavior problems in early adulthood using a general population sample. Based on 7,218 individuals from the Avon longitudinal study of parents and children, a three-step approach was used to model childhood conduct problem development and identify differences in early adult health and behavior problems. Childhood conduct problems were assessed on six occasions between age 4 and 13 and health and behavior outcomes were measured at age 18. Individuals who displayed early-onset persistent conduct problems throughout childhood were at greater risk for almost all forms of later problems. Individuals on the adolescent-onset conduct problem path consumed more tobacco and illegal drugs and engaged more often in risky sexual behavior than individuals without childhood conduct problems. Levels of health and behavior problems for individuals on the childhood-limited path were in between those for stable low and stable high trajectories. Childhood conduct problems are pervasive and substantially affect adjustment in early adulthood both in at-risk samples as shown in previous studies, but also in a general population sample. Knowing a child's developmental course can help to evaluate the risk for later maladjustment and be indicative of the need for early intervention.

  2. A Framework for Conducting ESL/EFL Construct Validation Studies.

    ERIC Educational Resources Information Center

    Mouw, John T.; Perkins, Kyle

    The purpose for which a test is used and the examinees' stage of learning are two anchor points that are incorporated into a suggested framework for conducting construct validation studies for tests of students with English as a second language (ESL) or English as a foreign language (EFL). The framework includes the use of generalizability theory,…

  3. Phylogenomic analysis of Copepoda (Arthropoda, Crustacea) reveals unexpected similarities with earlier proposed morphological phylogenies.

    PubMed

    Eyun, Seong-Il

    2017-01-19

    Copepods play a critical role in marine ecosystems but have been poorly investigated in phylogenetic studies. Morphological evidence supports the monophyly of copepods, whereas interordinal relationships continue to be debated. In particular, the phylogenetic position of the order Harpacticoida is still ambiguous and inconsistent among studies. Until now, a small number of molecular studies have been done using only a limited number or even partial genes and thus there is so far no consensus at the order-level. This study attempted to resolve phylogenetic relationships among and within four major copepod orders including Harpacticoida and the phylogenetic position of Copepoda among five other crustacean groups (Anostraca, Cladocera, Sessilia, Amphipoda, and Decapoda) using 24 nuclear protein-coding genes. Phylogenomics has confirmed the monophyly of Copepoda and Podoplea. However, this study reveals surprising differences with the majority of the copepod phylogenies and unexpected similarities with postembryonic characters and earlier proposed morphological phylogenies; More precisely, Cyclopoida is more closely related to Siphonostomatoida than to Harpacticoida which is likely the most basally-branching group of Podoplea. Divergence time estimation suggests that the origin of Harpacticoida can be traced back to the Devonian, corresponding well with recently discovered fossil evidence. Copepoda has a close affinity to the clade of Malacostraca and Thecostraca but not to Branchiopoda. This result supports the hypothesis of the newly proposed clades, Communostraca, Multicrustacea, and Allotriocarida but further challenges the validity of Hexanauplia and Vericrustacea. The first phylogenomic study of Copepoda provides new insights into taxonomic relationships and represents a valuable resource that improves our understanding of copepod evolution and their wide range of ecological adaptations.

  4. A Hepatocellular Carcinoma Case in a Patient Who had Immunity to Hepatitis B Virus Earlier

    PubMed Central

    Kaplan, Mustafa; Demirci, Selim; Altiparmak, Emin

    2016-01-01

    ABSTRACT Hepatocellular carcinoma (HCC) is the most common malignant tumor of the liver. Hepatitis B virus infection is one of the most important etilogical factors of HCC. In this case report, a patient with HCC previously infected and having ongoing immunity against hepatitis B virus will be discussed. How to cite this article Ates I, Kaplan M, Demirci S, Altiparmak E. A Hepatocellular Carcinoma Case in a Patient Who had Immunity to Hepatitis B Virus Earlier. Euroasian J Hepato-Gastroenterol 2016;6(1):82-83. PMID:29201732

  5. "Operation Workload" : a study of passenger energy expenditure during an emergency evacuation.

    DOT National Transportation Integrated Search

    1989-03-01

    In an earlier study at the Civil Aeromedical Institute, workloads were determined for passengers during an emergency evacuation. The evacuation tests were conducted in an orderly manner and were suggested as representative of a moderate workload. The...

  6. GUIDE TO CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOIL WASHING - INTERIM GUIDANCE

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (RI/FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation, and Liab...

  7. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOLVENT EXTRACTION - INTERIM GUIDANCE

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (RI/FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation and Liabi...

  8. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: THERMAL DESORPTION - INTERIM GUIDANCE

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (RI/FS) process and the remedial design remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation, and Liab...

  9. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: AEROBIC BIODEGRADATION REMEDY SCREENING

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (KU FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation, and L...

  10. Empirical corroboration of an earlier theoretical resolution to the UV paradox of insect polarized skylight orientation.

    PubMed

    Wang, Xin; Gao, Jun; Fan, Zhiguo

    2014-02-01

    It is surprising that many insect species use only the ultraviolet (UV) component of the polarized skylight for orientation and navigation purposes, while both the intensity and the degree of polarization of light from the clear sky are lower in the UV than at longer (blue, green, red) wavelengths. Why have these insects chosen the UV part of the polarized skylight? This strange phenomenon is called the "UV-sky-pol paradox". Although earlier several speculations tried to resolve this paradox, they did this without any quantitative data. A theoretical and computational model has convincingly explained why it is advantageous for certain animals to detect celestial polarization in the UV. We performed a sky-polarimetric approach and built a polarized skylight sensor that models the processing of polarization signals by insect photoreceptors. Using this model sensor, we carried out measurements under clear and cloudy sky conditions. Our results showed that light from the cloudy sky has maximal degree of polarization in the UV. Furthermore, under both clear and cloudy skies the angle of polarization of skylight can be detected with a higher accuracy. By this, we corroborated empirically the soundness of the earlier computational resolution of the UV-sky-pol paradox.

  11. Empirical corroboration of an earlier theoretical resolution to the UV paradox of insect polarized skylight orientation

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Gao, Jun; Fan, Zhiguo

    2014-02-01

    It is surprising that many insect species use only the ultraviolet (UV) component of the polarized skylight for orientation and navigation purposes, while both the intensity and the degree of polarization of light from the clear sky are lower in the UV than at longer (blue, green, red) wavelengths. Why have these insects chosen the UV part of the polarized skylight? This strange phenomenon is called the "UV-sky-pol paradox". Although earlier several speculations tried to resolve this paradox, they did this without any quantitative data. A theoretical and computational model has convincingly explained why it is advantageous for certain animals to detect celestial polarization in the UV. We performed a sky-polarimetric approach and built a polarized skylight sensor that models the processing of polarization signals by insect photoreceptors. Using this model sensor, we carried out measurements under clear and cloudy sky conditions. Our results showed that light from the cloudy sky has maximal degree of polarization in the UV. Furthermore, under both clear and cloudy skies the angle of polarization of skylight can be detected with a higher accuracy. By this, we corroborated empirically the soundness of the earlier computational resolution of the UV-sky-pol paradox.

  12. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false How will a feasibility study be conducted... Studies § 404.47 How will a feasibility study be conducted under this program? Feasibility studies will be... feasibility study, including the Principles and Guidelines (incorporated by reference at § 404.4). You can...

  13. Minimum-norm cortical source estimation in layered head models is robust against skull conductivity error☆☆☆

    PubMed Central

    Stenroos, Matti; Hauk, Olaf

    2013-01-01

    The conductivity profile of the head has a major effect on EEG signals, but unfortunately the conductivity for the most important compartment, skull, is only poorly known. In dipole modeling studies, errors in modeled skull conductivity have been considered to have a detrimental effect on EEG source estimation. However, as dipole models are very restrictive, those results cannot be generalized to other source estimation methods. In this work, we studied the sensitivity of EEG and combined MEG + EEG source estimation to errors in skull conductivity using a distributed source model and minimum-norm (MN) estimation. We used a MEG/EEG modeling set-up that reflected state-of-the-art practices of experimental research. Cortical surfaces were segmented and realistically-shaped three-layer anatomical head models were constructed, and forward models were built with Galerkin boundary element method while varying the skull conductivity. Lead-field topographies and MN spatial filter vectors were compared across conductivities, and the localization and spatial spread of the MN estimators were assessed using intuitive resolution metrics. The results showed that the MN estimator is robust against errors in skull conductivity: the conductivity had a moderate effect on amplitudes of lead fields and spatial filter vectors, but the effect on corresponding morphologies was small. The localization performance of the EEG or combined MEG + EEG MN estimator was only minimally affected by the conductivity error, while the spread of the estimate varied slightly. Thus, the uncertainty with respect to skull conductivity should not prevent researchers from applying minimum norm estimation to EEG or combined MEG + EEG data. Comparing our results to those obtained earlier with dipole models shows that general judgment on the performance of an imaging modality should not be based on analysis with one source estimation method only. PMID:23639259

  14. NMR-based fecal metabolomics fingerprinting as predictors of earlier diagnosis in patients with colorectal cancer.

    PubMed

    Lin, Yan; Ma, Changchun; Liu, Chengkang; Wang, Zhening; Yang, Jurong; Liu, Xinmu; Shen, Zhiwei; Wu, Renhua

    2016-05-17

    Colorectal cancer (CRC) is a growing cause of mortality in developing countries, warranting investigation into its earlier detection for optimal disease management. A metabolomics based approach provides potential for noninvasive identification of biomarkers of colorectal carcinogenesis, as well as dissection of molecular pathways of pathophysiological conditions. Here, proton nuclear magnetic resonance spectroscopy (1HNMR) -based metabolomic approach was used to profile fecal metabolites of 68 CRC patients (stage I/II=20; stage III=25 and stage IV=23) and 32 healthy controls (HC). Pattern recognition through principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) was applied on 1H-NMR processed data for dimension reduction. OPLS-DA revealed that each stage of CRC could be clearly distinguished from HC based on their metabolomic profiles. Successive analyses identified distinct disturbances to fecal metabolites of CRC patients at various stages, compared with those in cancer free controls, including reduced levels of acetate, butyrate, propionate, glucose, glutamine, and elevated quantities of succinate, proline, alanine, dimethylglycine, valine, glutamate, leucine, isoleucine and lactate. These altered fecal metabolites potentially involved in the disruption of normal bacterial ecology, malabsorption of nutrients, increased glycolysis and glutaminolysis. Our findings revealed that the fecal metabolic profiles of healthy controls can be distinguished from CRC patients, even in the early stage (stage I/II), highlighting the potential utility of NMR-based fecal metabolomics fingerprinting as predictors of earlier diagnosis in CRC patients.

  15. NMR-based fecal metabolomics fingerprinting as predictors of earlier diagnosis in patients with colorectal cancer

    PubMed Central

    Lin, Yan; Ma, Changchun; Liu, Chengkang; Wang, Zhening; Yang, Jurong; Liu, Xinmu; Shen, Zhiwei; Wu, Renhua

    2016-01-01

    Colorectal cancer (CRC) is a growing cause of mortality in developing countries, warranting investigation into its earlier detection for optimal disease management. A metabolomics based approach provides potential for noninvasive identification of biomarkers of colorectal carcinogenesis, as well as dissection of molecular pathways of pathophysiological conditions. Here, proton nuclear magnetic resonance spectroscopy (1HNMR) -based metabolomic approach was used to profile fecal metabolites of 68 CRC patients (stage I/II=20; stage III=25 and stage IV=23) and 32 healthy controls (HC). Pattern recognition through principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) was applied on 1H-NMR processed data for dimension reduction. OPLS-DA revealed that each stage of CRC could be clearly distinguished from HC based on their metabolomic profiles. Successive analyses identified distinct disturbances to fecal metabolites of CRC patients at various stages, compared with those in cancer free controls, including reduced levels of acetate, butyrate, propionate, glucose, glutamine, and elevated quantities of succinate, proline, alanine, dimethylglycine, valine, glutamate, leucine, isoleucine and lactate. These altered fecal metabolites potentially involved in the disruption of normal bacterial ecology, malabsorption of nutrients, increased glycolysis and glutaminolysis. Our findings revealed that the fecal metabolic profiles of healthy controls can be distinguished from CRC patients, even in the early stage (stage I/II), highlighting the potential utility of NMR-based fecal metabolomics fingerprinting as predictors of earlier diagnosis in CRC patients. PMID:27107423

  16. A feasibility study for conducting unattended night-time operations at WMKO

    NASA Astrophysics Data System (ADS)

    Stomski, Paul J.; Gajadhar, Sarah; Dahm, Scott; Jordan, Carolyn; Nordin, Tom

    2016-08-01

    In 2015, W. M. Keck Observatory conducted a study of the feasibility of conducting nighttime operations on Maunakea without any staff on the mountain. The study was motivated by the possibility of long term operational costs savings as well as other expected benefits. The goals of the study were to understand the technical feasibility and risk as well as to provide labor and cost estimates for implementation. The results of the study would be used to inform a decision about whether or not to fund and initiate a formal project aimed at the development of this new unattended nighttime operating capability. In this paper we will describe the study process as well as a brief summary of the results including the identified viable design alternative, the risk analysis, and the scope of work. We will also share the decisions made as a result of the study and current status of related follow-on activity.

  17. New evidence: data documenting parental support for earlier sexuality education.

    PubMed

    Barr, Elissa M; Moore, Michele J; Johnson, Tammie; Forrest, Jamie; Jordan, Melissa

    2014-01-01

    Numerous studies document support for sexuality education to be taught in high school, and often, in middle school. However, little research has been conducted addressing support for sexuality education in elementary schools. As part of the state Behavioral Risk Factor Surveillance System (BRFSS) Survey administration, the Florida Department of Health conducted the Florida Child Health Survey (FCHS) by calling back parents who had children in their home and who agreed to participate (N = 1715). Most parents supported the following sexuality education topics being taught specifically in elementary school: communication skills (89%), human anatomy/reproductive information (65%), abstinence (61%), human immunodeficiency virus (HIV)/sexually transmitted infections (STIs) (53%), and gender/sexual orientation issues (52%). Support was even greater in middle school (62-91%) and high school (72-91%) for these topics and for birth control and condom education. Most parents supported comprehensive sexuality education (40.4%), followed by abstinence-plus (36.4%) and abstinence-only (23.2%). Chi-square results showed significant differences in the type of sexuality education supported by almost all parent demographic variables analyzed including sex, race, marital status, and education. Results add substantial support for age-appropriate school-based sexuality education starting at the elementary school level, the new National Sexuality Education Standards, and funding to support evidence-based abstinence-plus or comprehensive sexuality education. © 2013, American School Health Association.

  18. Tunneling Conductivity and Piezoresistivity of Composites Containing Randomly Dispersed Conductive Nano-Platelets

    PubMed Central

    Oskouyi, Amirhossein Biabangard; Sundararaj, Uttandaraman; Mertiny, Pierre

    2014-01-01

    In this study, a three-dimensional continuum percolation model was developed based on a Monte Carlo simulation approach to investigate the percolation behavior of an electrically insulating matrix reinforced with conductive nano-platelet fillers. The conductivity behavior of composites rendered conductive by randomly dispersed conductive platelets was modeled by developing a three-dimensional finite element resistor network. Parameters related to the percolation threshold and a power-low describing the conductivity behavior were determined. The piezoresistivity behavior of conductive composites was studied employing a reoriented resistor network emulating a conductive composite subjected to mechanical strain. The effects of the governing parameters, i.e., electron tunneling distance, conductive particle aspect ratio and size effects on conductivity behavior were examined. PMID:28788580

  19. Quantifying the Economic Value and Quality of Life Impact of Earlier Influenza Vaccination

    PubMed Central

    Lee, Bruce Y.; Bartsch, Sarah M.; Brown, Shawn T.; Cooley, Philip; Wheaton, William D.; Zimmerman, Richard K.

    2015-01-01

    Background Influenza vaccination is administered throughout the influenza disease season, even as late as March. Given such timing, what is the value of vaccinating the population earlier than currently being practiced? Methods We used real data on when individuals were vaccinated in Allegheny County, Pennsylvania, and the following 2 models to determine the value of vaccinating individuals earlier (by the end of September, October, and November): Framework for Reconstructing Epidemiological Dynamics (FRED), an agent-based model (ABM), and FluEcon, our influenza economic model that translates cases from the ABM to outcomes and costs [health care and lost productivity costs and quality-adjusted life-years (QALYs)]. We varied the reproductive number (R0) from 1.2 to 1.6. Results Applying the current timing of vaccinations averted 223,761 influenza cases, $16.3 million in direct health care costs, $50.0 million in productivity losses, and 804 in QALYs, compared with no vaccination (February peak, R0 1.2). When the population does not have preexisting immunity and the influenza season peaks in February (R0 1.2–1.6), moving individuals who currently received the vaccine after September to the end of September could avert an additional 9634–17,794 influenza cases, $0.6–$1.4 million in direct costs, $2.1–$4.0 million in productivity losses, and 35–64 QALYs. Moving the vaccination of just children to September (R0 1.2–1.6) averted 11,366–1660 influenza cases, $0.6–$0.03 million in direct costs, $2.3–$0.2 million in productivity losses, and 42–8 QALYs. Moving the season peak to December increased these benefits, whereas increasing preexisting immunity reduced these benefits. Conclusion Even though many people are vaccinated well after September/October, they likely are still vaccinated early enough to provide substantial cost-savings. PMID:25590676

  20. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF... request assistance to conduct a feasibility study? To request assistance to conduct a feasibility study under § 404.11(a) or (b), consistent with Reclamation's recommendation in an appraisal report, you must...

  1. Onset of rigor mortis is earlier in red muscle than in white muscle.

    PubMed

    Kobayashi, M; Takatori, T; Nakajima, M; Sakurada, K; Hatanaka, K; Ikegaya, H; Matsuda, Y; Iwase, H

    2000-01-01

    Rigor mortis is thought to be related to falling ATP levels in muscles postmortem. We measured rigor mortis as tension determined isometrically in three rat leg muscles in liquid paraffin kept at 37 degrees C or 25 degrees C--two red muscles, red gastrocnemius (RG) and soleus (SO) and one white muscle, white gastrocnemius (WG). Onset, half and full rigor mortis occurred earlier in RG and SO than in WG both at 37 degrees C and at 25 degrees C even though RG and WG were portions of the same muscle. This suggests that rigor mortis directly reflects the postmortem intramuscular ATP level, which decreases more rapidly in red muscle than in white muscle after death. Rigor mortis was more retarded at 25 degrees C than at 37 degrees C in each type of muscle.

  2. Challenges of Conducting a Self-Study Process: Small Two-Year Institutions.

    ERIC Educational Resources Information Center

    Weeks, Richard G., Jr.

    A description is provided of the accreditation self-study process employed by Northwest Community College (NCC), along with a copy of the final self-study report. First, information is presented on how the current college organizational structure was used to conduct the self-study, including explanations of the role of the President's Advisory…

  3. Carbon Fibers Conductivity Studies

    NASA Technical Reports Server (NTRS)

    Yang, C. Y.; Butkus, A. M.

    1980-01-01

    In an attempt to understand the process of electrical conduction in polyacrylonitrile (PAN)-based carbon fibers, calculations were carried out on cluster models of the fiber consisting of carbon, nitrogen, and hydrogen atoms using the modified intermediate neglect of differential overlap (MINDO) molecular orbital (MO) method. The models were developed based on the assumption that PAN carbon fibers obtained with heat treatment temperatures (HTT) below 1000 C retain nitrogen in a graphite-like lattice. For clusters modeling an edge nitrogen site, analysis of the occupied MO's indicated an electron distribution similar to that of graphite. A similar analysis for the somewhat less stable interior nitrogen site revealed a partially localized II electron distribution around the nitrogen atom. The differences in bonding trends and structural stability between edge and interior nitrogen clusters led to a two-step process proposed for nitrogen evolution with increasing HTT.

  4. Electron beam irradiated polymer electrolyte film: Morphology, dielectric and AC conductivity studies

    NASA Astrophysics Data System (ADS)

    Yesappa, L.; Niranjana, M.; Ashokkumar, S. P.; Vijeth, H.; Ganesh, S.; Devendrappa, H.

    2018-05-01

    The polymer (PVdF-co-HFP: LiClO4=90:10, PHL10) electrolyte films prepared by solution casting method and studied morphology, dielectric properties and ac conductivity before and after electron beam (EB) irradiation. The polarized optical micrographs reveals size of spherulite reduced with increasing EB dose represents increase in amorphousity. The dielectric measurements were studied at different temperatures and observed increase with frequency at different temperatures upon EB irradiation. The ac conductivity increases with frequency due to effect of EB dose.

  5. Quantitative study of bundle size effect on thermal conductivity of single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Feng, Ya; Inoue, Taiki; An, Hua; Xiang, Rong; Chiashi, Shohei; Maruyama, Shigeo

    2018-05-01

    Compared with isolated single-walled carbon nanotubes (SWNTs), thermal conductivity is greatly impeded in SWNT bundles; however, the measurement of the bundle size effect is difficult. In this study, the number of SWNTs in a bundle was determined based on the transferred horizontally aligned SWNTs on a suspended micro-thermometer to quantitatively study the effect of the bundle size on thermal conductivity. Increasing the bundle size significantly degraded the thermal conductivity. For isolated SWNTs, thermal conductivity was approximately 5000 ± 1000 W m-1 K-1 at room temperature, three times larger than that of the four-SWNT bundle. The logarithmical deterioration of thermal conductivity resulting from the increased bundle size can be attributed to the increased scattering rate with neighboring SWNTs based on the kinetic theory.

  6. Influence of conduct problems and depressive symptomatology on adolescent substance use: developmentally proximal versus distal effects.

    PubMed

    Maslowsky, Julie; Schulenberg, John E; Zucker, Robert A

    2014-04-01

    The identification of developmentally specific windows at which key predictors of adolescent substance use are most influential is a crucial task for informing the design of appropriately targeted substance use prevention and intervention programs. The current study examined effects of conduct problems and depressive symptomatology on changes in alcohol, cigarette, and marijuana from 8th through 12th grade. We examined the effects of relatively developmentally distal versus proximal mental health problems on adolescent substance use and tested for gender differences. With a national, longitudinal sample from the Monitoring the Future study (N = 3,014), structural equation modeling was used to test the effects of 8th and 10th grade conduct problems and depressive symptomatology on subsequent changes in alcohol, cigarette, and marijuana use from 8th through 12th grade. Results indicated that relatively distal (8th grade) mental health problems were stronger predictors of increases in alcohol, cigarette, and marijuana use than were relatively more proximal (10th grade) mental health problems. Eighth grade conduct problems had the strongest effects on alcohol and marijuana use, and 8th grade depressive symptomatology had the strongest effects on cigarette use. Few gender differences were observed. These results suggest that intervening in earlier appearing conduct problems and depressive symptomatology may lead to a reduction in adolescent substance use in 10th and 12th grades and beyond. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  7. Fibroblast proliferation alters cardiac excitation conduction and contraction: a computational study.

    PubMed

    Zhan, He-qing; Xia, Ling; Shou, Guo-fa; Zang, Yun-liang; Liu, Feng; Crozier, Stuart

    2014-03-01

    In this study, the effects of cardiac fibroblast proliferation on cardiac electric excitation conduction and mechanical contraction were investigated using a proposed integrated myocardial-fibroblastic electromechanical model. At the cellular level, models of the human ventricular myocyte and fibroblast were modified to incorporate a model of cardiac mechanical contraction and cooperativity mechanisms. Cellular electromechanical coupling was realized with a calcium buffer. At the tissue level, electrical excitation conduction was coupled to an elastic mechanics model in which the finite difference method (FDM) was used to solve electrical excitation equations, and the finite element method (FEM) was used to solve mechanics equations. The electromechanical properties of the proposed integrated model were investigated in one or two dimensions under normal and ischemic pathological conditions. Fibroblast proliferation slowed wave propagation, induced a conduction block, decreased strains in the fibroblast proliferous tissue, and increased dispersions in depolarization, repolarization, and action potential duration (APD). It also distorted the wave-front, leading to the initiation and maintenance of re-entry, and resulted in a sustained contraction in the proliferous areas. This study demonstrated the important role that fibroblast proliferation plays in modulating cardiac electromechanical behaviour and which should be considered in planning future heart-modeling studies.

  8. Fibroblast proliferation alters cardiac excitation conduction and contraction: a computational study*

    PubMed Central

    Zhan, He-qing; Xia, Ling; Shou, Guo-fa; Zang, Yun-liang; Liu, Feng; Crozier, Stuart

    2014-01-01

    In this study, the effects of cardiac fibroblast proliferation on cardiac electric excitation conduction and mechanical contraction were investigated using a proposed integrated myocardial-fibroblastic electromechanical model. At the cellular level, models of the human ventricular myocyte and fibroblast were modified to incorporate a model of cardiac mechanical contraction and cooperativity mechanisms. Cellular electromechanical coupling was realized with a calcium buffer. At the tissue level, electrical excitation conduction was coupled to an elastic mechanics model in which the finite difference method (FDM) was used to solve electrical excitation equations, and the finite element method (FEM) was used to solve mechanics equations. The electromechanical properties of the proposed integrated model were investigated in one or two dimensions under normal and ischemic pathological conditions. Fibroblast proliferation slowed wave propagation, induced a conduction block, decreased strains in the fibroblast proliferous tissue, and increased dispersions in depolarization, repolarization, and action potential duration (APD). It also distorted the wave-front, leading to the initiation and maintenance of re-entry, and resulted in a sustained contraction in the proliferous areas. This study demonstrated the important role that fibroblast proliferation plays in modulating cardiac electromechanical behaviour and which should be considered in planning future heart-modeling studies. PMID:24599687

  9. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... specimen in a manner that precludes error in the recording and storage of data. (d) Records of gross... that specimen histopathologically. (e) All data generated during the conduct of a nonclinical laboratory study, except those that are generated by automated data collection systems, shall be recorded...

  10. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... specimen in a manner that precludes error in the recording and storage of data. (d) Records of gross... that specimen histopathologically. (e) All data generated during the conduct of a nonclinical laboratory study, except those that are generated by automated data collection systems, shall be recorded...

  11. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... specimen in a manner that precludes error in the recording and storage of data. (d) Records of gross... that specimen histopathologically. (e) All data generated during the conduct of a nonclinical laboratory study, except those that are generated by automated data collection systems, shall be recorded...

  12. Decreased length of stay and earlier oral feeding associated with standardized postoperative clinical care for total gastrectomies at a cancer center.

    PubMed

    Selby, Luke V; Rifkin, Marissa B; Yoon, Sam S; Ariyan, Charlotte E; Strong, Vivian E

    2016-09-01

    Standardization of postoperative care has been shown to decrease postoperative length of stay. In June 2009, we standardized postoperative care for all gastrectomies at our institution. Four years' worth of total gastrectomies (2 years prior to standardization and 2 years after standardization) were reviewed to determine the effect of standardization on postoperative care, length of stay, complications, and readmissions. Between June 2007 and July 2011, 99 patients underwent curative intent open total gastrectomy: 51 patients prior to standardization, and 48 patients poststandardization. Patients were predominantly male (70%); median age was 63; and median body mass index was 26. Standardization of postoperative care was associated with a decrease in median time to beginning both clear liquids and a postgastrectomy diet, earlier removal of epidural catheters, earlier use of oral pain medication, less time receiving intravenous fluids, and decreased length of stay (all P < .01). Groups showed no differences in complication rates, complication severity, diet intolerance, return to our Urgent Care Center, or readmission. Institution of standardized postoperative orders for total gastrectomy was associated with a significantly decreased length of stay and earlier oral feeding without increasing postoperative complications, early postoperative outpatient visits, or readmissions. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Online Instruction, E-Learning, and Student Satisfaction: A Three Year Study

    ERIC Educational Resources Information Center

    Cole, Michele T.; Shelley, Daniel J.; Swartz, Louis B.

    2014-01-01

    This article presents the results of a three-year study of graduate and undergraduate students' level of satisfaction with online instruction at one university. The study expands on earlier research into student satisfaction with e-learning. Researchers conducted a series of surveys over eight academic terms. Five hundred and fifty-three students…

  14. Conducting Simulation Studies in the R Programming Environment.

    PubMed

    Hallgren, Kevin A

    2013-10-12

    Simulation studies allow researchers to answer specific questions about data analysis, statistical power, and best-practices for obtaining accurate results in empirical research. Despite the benefits that simulation research can provide, many researchers are unfamiliar with available tools for conducting their own simulation studies. The use of simulation studies need not be restricted to researchers with advanced skills in statistics and computer programming, and such methods can be implemented by researchers with a variety of abilities and interests. The present paper provides an introduction to methods used for running simulation studies using the R statistical programming environment and is written for individuals with minimal experience running simulation studies or using R. The paper describes the rationale and benefits of using simulations and introduces R functions relevant for many simulation studies. Three examples illustrate different applications for simulation studies, including (a) the use of simulations to answer a novel question about statistical analysis, (b) the use of simulations to estimate statistical power, and (c) the use of simulations to obtain confidence intervals of parameter estimates through bootstrapping. Results and fully annotated syntax from these examples are provided.

  15. Earlier Endpoints Are Required for Hemorrhagic Shock Trials among Severely Injured Patients

    PubMed Central

    Fox, Erin E.; Holcomb, John B.; Wade, Charles E.; Bulger, Eileen M.; Tilley, Barbara C.

    2016-01-01

    Background Choosing the appropriate endpoint for a trauma hemorrhage control trial can determine the likelihood of its success. Recent Phase 3 trials and observational studies have used 24-hour and/or 30-day all-cause mortality as the primary endpoint and some have not used exception from informed consent (EFIC), resulting in multiple failed trials. Five recent high-quality prospective studies among 4,064 hemorrhaging trauma patients provide new evidence to support earlier primary endpoints. Methods The goal of this project was to determine the optimal endpoint for hemorrhage control trials using existing literature and new analyses of previously published data. Results Recent studies among bleeding trauma patients show that hemorrhagic deaths occur rapidly, at a high rate, and in a consistent pattern. Early preventable deaths among trauma patients are largely due to hemorrhage and the median time to hemorrhagic death from admission is 2.0-2.6 hours. Approximately 85% of hemorrhagic deaths occur within 6 hours. The hourly mortality rate due to traumatic injury decreases rapidly after enrollment from 4.6% per hour at 1 hour post-enrollment to 1% per hour at 6 hours to <0.1% per hour by 9 hours and thereafter. Early primary endpoints (within 6 hours) have critically important benefits for hemorrhage control trials, including being congruent with the median time to hemorrhagic death, biologic plausibility, and enabling the use of all-cause mortality, which is definitive and objective. Conclusions Primary endpoints should be congruent with the timing of the disease process. Therefore, if a resuscitation/hemorrhage control intervention is under study, a primary endpoint of all-cause mortality evaluated within the first 6 hours is appropriate. Before choosing the timing of the primary endpoint for a large multicenter trial, we recommend performing a Phase 2 trial under EFIC to better understand the effects of the hemorrhage control intervention and distribution of time

  16. AC conductivity and Dielectric Study of Chalcogenide Glasses of Se-Te-Ge System

    NASA Astrophysics Data System (ADS)

    Salman, Fathy

    2004-01-01

    The ac conductivity and dielectric properties of glassy system SexTe79 - xGe21, with x = 11, 14, 17 at.%, has been studied at temperatures 300 to 450 K and over a wide range of frequencies (50 Hz to 500 kHz). Experimental results indicate that the ac conductivity and the dielectric constants depend on temperature, frequency and Se content. The conductivity as a function of frequency exhibited two components: dc conductivity s dc, and ac conductivity s ac, where s ac ˜ w s. The mechanism of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping model (CBH). The activation energies are estimated and discussed. The dependence of ac conductivity and dielectric constants on the Se content x can be interpreted as the effect of Se fraction on the positional disorder. The impedance plot at each temperature appeared as a semicircle passes through the origin. Each semicircle is represented by an equivalent circuit of parallel resistance Rb and capacitance Cb.

  17. Low noise and conductively cooled microchannel plates

    NASA Technical Reports Server (NTRS)

    Feller, W. B.

    1990-01-01

    Microchannel plate (MCP) dynamic range has recently been enhanced for both very low and very high input flux conditions. Improvements in MCP manufacturing technology reported earlier have led to MCPs with substantially reduced radioisotope levels, giving dramatically lower internal background-counting rates. An update is given on the Galileo low noise MCP. Also, new results in increasing the MCP linear counting range for high input flux densities are presented. By bonding the active face of a very low resistance MCP (less than 1 megaohm) to a substrate providing a conductive path for heat transport, the bias current limit (hence, MCP output count rate limit) can be increased up to two orders of magnitude. Normal pulse-counting MCP operation was observed at bias currents of several mA when a curved-channel MCP (80:1) was bonded to a ceramic multianode substrate; the MCP temperature rise above ambient was less than 40 C.

  18. BATCH AND COLUMN STUDIES ON BTEX BIODEGRADATION BY AQUIFER MICROORGANISMS UNDER DENITRIFYING CONDITIONS

    EPA Science Inventory

    The objective of these laboratory experiments was to determine the role nitrate plays in enhancing the biodegradation of fuel contaminated groundwater. Column studies were conducted to simulate the nitrate field demonstration project carried out earlier at Traverse City, MI so a...

  19. Earlier Detection of Tumor Treatment Response Using Magnetic Resonance Diffusion Imaging with Oscillating Gradients

    PubMed Central

    Colvin, Daniel C.; Loveless, Mary E.; Does, Mark D.; Yue, Zou; Yankeelov, Thomas E.; Gore, John C.

    2011-01-01

    An improved method for detecting early changes in tumors in response to treatment, based on a modification of diffusion-weighted magnetic resonance imaging, has been demonstrated in an animal model. Early detection of therapeutic response in tumors is important both clinically and in pre-clinical assessments of novel treatments. Non-invasive imaging methods that can detect and assess tumor response early in the course of treatment, and before frank changes in tumor morphology are evident, are of considerable interest as potential biomarkers of treatment efficacy. Diffusion-weighted magnetic resonance imaging is sensitive to changes in water diffusion rates in tissues that result from structural variations in the local cellular environment, but conventional methods mainly reflect changes in tissue cellularity and do not convey information specific to micro-structural variations at sub-cellular scales. We implemented a modified imaging technique using oscillating gradients of the magnetic field for evaluating water diffusion rates over very short spatial scales that are more specific for detecting changes in intracellular structure that may precede changes in cellularity. Results from a study of orthotopic 9L gliomas in rat brains indicate that this method can detect changes as early as 24 hours following treatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), when conventional approaches do not find significant effects. These studies suggest that diffusion imaging using oscillating gradients may be used to obtain an earlier indication of treatment efficacy than previous magnetic resonance imaging methods. PMID:21190804

  20. Study on Thermal Conductivities of Aromatic Polyimide Aerogels.

    PubMed

    Feng, Junzong; Wang, Xin; Jiang, Yonggang; Du, Dongxuan; Feng, Jian

    2016-05-25

    Polyimide aerogels for low density thermal insulation materials were produced by 4,4'-diaminodiphenyl ether and 3,3',4,4'-biphenyltetracarboxylic dianhydride, cross-linked with 1,3,5-triaminophenoxybenzene. The densities of obtained polyimide aerogels are between 0.081 and 0.141 g cm(-3), and the specific surface areas are between 288 and 322 m(2) g(-1). The thermal conductivities were measured by a Hot Disk thermal constant analyzer. The value of the measured thermal conductivity under carbon dioxide atmosphere is lower than that under nitrogen atmosphere. Under pressure of 5 Pa at -130 °C, the thermal conductivity is the lowest, which is 8.42 mW (m K)(-1). The polyimide aerogels have lower conductivity [30.80 mW (m K)(-1)], compared to the value for other organic foams (polyurethane foam, phenolic foam, and polystyrene foam) with similar apparent densities under ambient pressure at 25 °C. The results indicate that polyimide aerogel is an ideal insulation material for aerospace and other applications.

  1. Conductivity of graphene in the framework of Dirac model: Interplay between nonzero mass gap and chemical potential

    NASA Astrophysics Data System (ADS)

    Klimchitskaya, G. L.; Mostepanenko, V. M.; Petrov, V. M.

    2017-12-01

    The complete theory of electrical conductivity of graphene at arbitrary temperature is developed with taking into account mass-gap parameter and chemical potential. Both the in-plane and out-of-plane conductivities of graphene are expressed via the components of the polarization tensor in (2+1)-dimensional space-time analytically continued to the real frequency axis. Simple analytic expressions for both the real and imaginary parts of the conductivity of graphene are obtained at zero and nonzero temperature. They demonstrate an interesting interplay depending on the values of mass gap and chemical potential. In the local limit, several results obtained earlier using various approximate and phenomenological approaches are reproduced, refined, and generalized. The numerical computations of both the real and imaginary parts of the conductivity of graphene are performed to illustrate the obtained results. The analytic expressions for the conductivity of graphene obtained in this paper can serve as a guide in the comparison between different theoretical approaches and between experiment and theory.

  2. Undergraduate Conductors' and Conducting Teachers' Perceptions of Basic Conducting Efficacy

    ERIC Educational Resources Information Center

    Silvey, Brian A.; Baumgartner, Christopher M.

    2016-01-01

    The purpose of this study was to examine undergraduate conductors' and conducting teachers' perceptions about basic conducting efficacy. At the beginning and end of the semester, undergraduate students (N = 19) enrolled in a basic conducting course (a) were surveyed about the importance of certain skills necessary for being an effective conductor…

  3. A DEFINITION OF CURIOSITY, A FACTOR ANALYSIS STUDY.

    ERIC Educational Resources Information Center

    MAW, WALLACE H.

    AN INVESTIGATION WAS CONDUCTED TO DETERMINE A DEFINITION OF CURIOSITY THAT WOULD HELP IDENTIFY PERSONALITY PATTERNS OF CHILDREN WHO ARE MOST LIKELY TO BE EITHER HIGH OR LOW IN CURIOSITY. DATA COLLECTED IN EARLIER STUDIES WERE FACTOR ANALYZED TO IDENTIFY THE PERSONAL AND SOCIAL VARIABLES THAT DIFFERENTIATE CHILDREN HIGH IN CURIOSITY FROM THOSE LOW…

  4. The decision to conduct a head-to-head comparative trial: a game-theoretic analysis.

    PubMed

    Mansley, Edward C; Elbasha, Elamin H; Teutsch, Steven M; Berger, Marc L

    2007-01-01

    Recent Medicare legislation calls on the Agency for Healthcare Research and Quality to conduct research related to the comparative effectiveness of health care items and services, including prescription drugs. This reinforces earlier calls for head-to-head comparative trials of clinically relevant treatment alternatives. Using a game-theoretic model, the authors explore the decision of pharmaceutical companies to conduct such trials. The model suggests that an important factor affecting this decision is the potential loss in market share and profits following a result of inferiority or comparability. This hidden cost is higher for the market leader than the market follower, making it less likely that the leader will choose to conduct a trial. The model also suggests that in a full-information environment, it will never be the case that both firms choose to conduct such a trial. Furthermore, if market shares and the probability of proving superiority are similar for both firms, it is quite possible that neither firm will choose to conduct a trial. Finally, the results indicate that incentives that offset the direct cost of a trial can prevent a no-trial equilibrium, even when both firms face the possibility of an inferior outcome.

  5. Can Biannual Ultrasound Surveillance Detect Smaller Second Cancers or Detect Cancers Earlier in Patients with Breast Cancer History?

    PubMed

    You, Jai Kyung; Song, Mi Kyung; Kim, Min Jung; Kim, Eun-Kyung; Moon, Hee Jung; Youk, Ji Hyun; Yoon, Jung Hyun; Park, Vivian Youngjean; Park, Seho; Kim, Seung Il; Park, Byeong-Woo

    2018-07-01

    The aim of the work described here was to evaluate whether surveillance with biannual ultrasound (US) plus annual mammography (biannual group) for women with a history of breast cancer surgery results in earlier detection or in the detection of smaller second cancers than annual US plus mammography (annual group). Additionally, we compared the prevalence of distant metastases or palpable second cancers between the biannual and annual groups. The institutional review board of our institution approved this retrospective study, and patient consent was waived. Between January 2011 and December 2012, we retrospectively reviewed the clinical and imaging follow-up of 3023 patients with mammographic and US surveillance after breast cancer surgery to assess second cancers detected by local surveillance (locoregional recurrence, contralateral breast cancer or distant metastasis). The biannual and annual groups were divided with respect to the mean surveillance interval and compared with respect to clinicopathologic findings. Multivariable logistic regression with propensity score methods was used to examine the effect of the type of surveillance on outcomes. As for the size of the second cancer, no difference was seen between the biannual and annual groups (12.8 ± 6.6 mm vs. 14.1 ± 7.1 mm, p = 0.461); neither was there a significant difference between the groups in the presence of symptoms at the time of diagnosis of the second cancer (17.0% [8/47] vs. 10% [2/20], p = 0.711). Regardless of detection by local surveillance, the prevalence of distant metastases did not differ between the two groups (1.1% [27/2370] vs. 1.0% [7/653], p = 0.88) on univariate or multivariate analysis. The results of our retrospective study indicate that second cancers detected by biannual US surveillance in patients with a history of breast cancer surgery are not smaller and do not occur earlier than those detected by annual US surveillance. However, a randomized

  6. Dynamical mechanisms of conducted vasoreactivity: minimalistic modeling study

    NASA Astrophysics Data System (ADS)

    Kuryshova, Ekaterina A.; Rogatina, Kristina V.; Postnov, Dmitry E.

    2018-04-01

    Endothelial cells are cells lining the inner surface of the blood and lymphatic vessels, they separate the bloodstream from the deeper layers of the vascular wall. Earlier endothelium was considered only as a passive barrier between blood and tissues. However, it has now become apparent that endothelial cells, specifically reacting to different molecular signals generated locally and remotely, perform a variety of functions. Simulation of large vascular networks requires the development of specialized models of autoregulation of vascular tone. On the one hand, such models should have a strong support for cellular dynamics, on the other - be as computationally efficient as possible. A model of a two-dimensional cylindrical array of endothelial cells is proposed on the basis of the integral description by means of the whole-cell CVC. The process of propagation of hyperpolarizing and depolarizing pulses is investigated depending on the statistics of cell distribution between the two main types. Endothelial cells are considered as a dynamic system possessing bistability. Based on the articles, the results of the distribution of the resting-potential values were repeated, the propagation of the hyperpolarizing pulse was observed, the endothelial cell chain supported the propagation of the wave switching to a hyperpolarized state, and then the return wave returned to its original state.

  7. Lessons Learned During the Conduct of Clinical Studies in The Dental PBRN

    PubMed Central

    Gilbert, Gregg H.; Richman, Joshua S.; Gordan, Valeria V.; Rindal, D. Brad; Fellows, Jeffrey L.; Benjamin, Paul L.; Wallace-Dawson, Martha; Williams, O. Dale

    2012-01-01

    Effectively addressing challenges of conducting research in nonacademic settings is crucial to its success. A dental practice-based research network called The Dental Practice-Based Research Network (DPBRN) is comprised of practitioner-investigators in two health maintenance organizations, several universities, many U.S. states, and three Scandinavian countries. Our objective in this article is to describe lessons learned from conducting studies in this research context; the studies are conducted by clinicians in community settings who may be doing their first research study. To date, twenty-one studies have been completed or are in implementation. These include a broad range of topic areas, enrollment sizes, and study designs. A total of 1,126 practitioner-investigators have participated in at least one study. After excluding one study because it involved electronic records queries only, these studies included more than 70,000 patient/participant units. Because the DPBRN is committed to being both practitioner- and patient-driven, all studies must be approved by its Executive Committee and a formal study section of academic clinical scientists. As a result of interacting with a diverse range of institutional and regulatory entities, funding agencies, practitioners, clinic staff, patients, academic scientists, and geographic areas, twenty-three key lessons have been learned. Patients’ acceptance of these studies has been very high, judging from high participation rates and their completion of data forms. Early studies substantially informed later studies with regard to study design, practicality, forms design, informed consent process, and training and monitoring methods. Although time-intensive and complex, these solutions improved acceptability of practice-based research to patients, practitioners, and university researchers. PMID:21460266

  8. Methodological, Theoretical, Infrastructural, and Design Issues in Conducting Good Outcome Studies

    ERIC Educational Resources Information Center

    Kelly, Michael P.; Moore, Tessa A.

    2011-01-01

    This article outlines a set of methodological, theoretical, and other issues relating to the conduct of good outcome studies. The article begins by considering the contribution of evidence-based medicine to the methodology of outcome research. The lessons which can be applied in outcome studies in nonmedical settings are described. The article…

  9. Conducting a narrative analysis.

    PubMed

    Emden, C

    1998-07-01

    This paper describes the process of narrative analysis as undertaken within a nursing study on scholars and scholarship. If follows an earlier paper titled: Theoretical perspectives on narrative inquiry that described the influencing ideas of Bruner (1987) and Roof (1994) upon the same study. Analysis procedures are described here in sufficient detail for other researchers wishing to implement a similar approach to do so. The process as described has two main components: (A) strategies of 'core story creation' and 'employment'; and (B) issues and dilemmas of narrative analysis, especially relating to rigour. The ideas of Polkinghorne (1988), Mishler (1986), and Labov (in Mishler 1986a) are introduced in so far as they impinge upon the analysis process. These relate especially to the development of key terms, and to the analysis strategies of core story creation and employment. Outcomes of the study in question are termed 'Signposting the lived-world of scholarship'.

  10. 76 FR 75875 - Plan for Conduct of 2012 Electric Transmission Congestion Study

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-05

    ... DEPARTMENT OF ENERGY Plan for Conduct of 2012 Electric Transmission Congestion Study AGENCY... preparation of a study of electric transmission congestion pursuant to section 216(a)(1) of the Federal Power...-register at this Web site: http://energy.gov/oe/congestion-study-2012 . [[Page 75876

  11. A general population twin study of conduct problems and the auditory P300 waveform.

    PubMed

    Bertoletti, Eleonora; Michelini, Giorgia; Moruzzi, Sara; Ferrer, Giuseppina; Ferini-Strambi, Luigi; Stazi, Maria Antonietta; Ogliari, Anna; Battaglia, Marco

    2014-01-01

    Reduced amplitude of the P300 event-related potential has been consistently associated with a variety of externalising problems, including conduct disorder. The few available genetically-informative studies of these relationships, however, were conducted among adolescents/adults (i.e., at an age when conduct disorder has typically already become manifest). Among 200 general population twins with a mean age of 9 years (range 6-14 years), we studied the relationship between the P300 waveform elicited by an auditory oddball task and the DSM-oriented conduct problems scale of the Child Behavior Checklist 6-18. Conduct problems scores were negatively and significantly correlated (r = -0.19, p = 0.01) with P300 amplitude; correlations between P300 amplitude and the other DSM-oriented Child Behavior Checklist scales were non-significant, except for oppositional defiant problems (p = 0.01). We found moderate heritability estimates for both P300 amplitude (0.58, CI:0.37;0.73) and conduct problems (0.52, CI:0.25;0.70). Bivariate twin analyses indicated that the covariation between these two phenotypes can be explained by additive genetic factors only, with a genetic correlation of -0.33. An association between reduced P300 amplitude and conduct problems can be substantiated already in childhood, at an age that precedes the most typical onset of conduct disorder. This relationship appears to be genetic in nature. Reduced P300 amplitude can represent a valuable marker for conduct problems, and can contribute to the early identification of children at high-risk for conduct disorder.

  12. Developmental Associations Between Conduct Problems and Expressive Language in Early Childhood: A Population-Based Study.

    PubMed

    Girard, Lisa-Christine; Pingault, Jean-Baptiste; Doyle, Orla; Falissard, Bruno; Tremblay, Richard E

    2016-08-01

    Conduct problems have been associated with poor language development, however the direction of this association in early childhood remains unclear. This study examined the longitudinal directional associations between conduct problems and expressive language ability. Children enrolled in the UK Millennium Cohort Study (N = 14, 004; 50.3 % boys) were assessed at 3 and 5 years of age. Parent reports of conduct problems and standardised assessments of expressive language were analyzed using cross-lagged modeling. Conduct problems at 3 years was associated with poorer expressive language at 5 years and poorer expressive language at 3 years was associated with increased conduct problems by 5 years. The results support reciprocal associations, rather than a specific unidirectional path, which is commonly found with samples of older children. The emergence of problems in either domain can thus negatively impact upon the other over time, albeit the effects were modest. Studies examining the effects of intervention targeting conduct problems and language acquisition prior to school entry may be warranted in testing the efficacy of prevention programmes related to conduct problems and poor language ability early in childhood.

  13. Effect of nifedipine on atrioventricular conduction as compared with verapamil. Intracardiac electrophysiological study.

    PubMed Central

    Rowland, E; Evans, T; Krikler, D

    1979-01-01

    Intravenous nifedipine, a powerful calcium antagonist, had no obvious effect on atrioventricular conduction when administered to 11 patients during routine intracardiac electrophysiological studies. Verapamil on the other hand showed potent antiarrhythmic properties, depressing atrioventricular nodal conduction. Nifedipine thus appears safe in patients with angina pectoris who have disorders of atrioventricular nodal conduction, and in those receiving beta-adrenergic blocking drugs. There appear to be differential effects on the slow inward channels of cardiac cells with different 'calcium antagonists'. PMID:486272

  14. Infliximab for uveitis of Behçet's syndrome: a trend for earlier initiation.

    PubMed

    Guzelant, Gul; Ucar, Didar; Esatoglu, Sinem Nihal; Hatemi, Gulen; Ozyazgan, Yilmaz; Yurdakul, Sebahattin; Seyahi, Emire; Yazici, Hasan; Hamuryudan, Vedat

    2017-01-01

    The prognosis of uveitis in Behçet's syndrome (BS) has improved over decades. Whether this is related to the use of more aggressive management strategies is not known. This is a retrospective study of BS patients who received infliximab (IFX) for refractory eye disease between 2003-2015. The patients were divided into two groups according to the date of onset of in IFX treatment as before and after 2013. We compared the two groups in terms of disease characteristics at the onset of IFX treatment and response to treatment. There were 43 patients in the old and 14 patients in the new group. The duration of uveitis and previous immunosuppressive treatment before the initiation of IFX were significantly shorter in the new group compared to the old group (p=0.043 and p=0.028, respectively). The baseline visual acuity (VA) at the initiation of IFX was better in the new group, but this was only significant for the left eye. Treatment with IFX was effective in both groups in preserving VA and this was more pronounced in the new group. Attack frequency under IFX was significantly lower in the new group (p<0.001). IFX seems to be initiated earlier and also in less severe cases during the course of BS uveitis than before. Despite the few numbers of patients and relatively short duration of follow-up, our results give a hint that this change has improved the outcome.

  15. Temperature dependence of conductivity measurement for conducting polymer

    NASA Astrophysics Data System (ADS)

    Gutierrez, Leandro; Duran, Jesus; Isah, Anne; Albers, Patrick; McDougall, Michael; Wang, Weining

    2014-03-01

    Conducting polymer-based solar cells are the newest generation solar cells. While research on this area has been progressing, the efficiency is still low because certain important parameters of the solar cell are still not well understood. It is of interest to study the temperature dependence of the solar cell parameters, such as conductivity of the polymer, open circuit voltage, and reverse saturation current to gain a better understanding on the solar cells. In this work, we report our temperature dependence of conductivity measurement using our in-house temperature-varying apparatus. In this project, we designed and built a temperature varying apparatus using a thermoelectric cooler module which gives enough temperature range as we need and costs much less than a cryostat. The set-up of the apparatus will be discussed. Temperature dependence of conductivity measurements for PEDOT:PSS films with different room-temperature conductivity will be compared and discussed. NJSGC-NASA Fellowship grant

  16. Impact of unilateral conductive hearing loss due to aural atresia on academic performance in children.

    PubMed

    Kesser, Bradley W; Krook, Kaelyn; Gray, Lincoln C

    2013-09-01

    This study evaluates the effect of unilateral conductive hearing loss secondary to aural atresia on elementary school children's academic performance. Case control survey and review of audiometric data. One hundred thirty-two surveys were mailed to families of children with aural atresia, and 48 surveys were sent to families of children with unilateral sensorineural hearing loss (SNHL) to identify rates of grade retention, use of any resource, and behavioral problems. Audiometric data of the cohort were tabulated. Of the 40 atresia patients, none repeated a grade, but 65% needed some resources: 12.5% currently use a hearing aid, 32.5% use(d) a frequency-modulated system in school, 47.5% had an Individualized Education Plan, and 45% utilized speech therapy. Compared to the unilateral SNHL group and a cohort of children with unilateral SNHL in an earlier study, children with unilateral atresia were less likely to repeat a grade. Children in both unilateral atresia and SNHL groups were more likely to utilize some resource in the academic setting compared to the unilateral SNHL children in the prior study. Unilateral conductive hearing loss due to aural atresia has an impact on academic performance in children, although not as profound when compared to children with unilateral SNHL. The majority of these children with unilateral atresia utilize resources in the school setting. Parents, educators, and health care professionals should be aware of the impact of unilateral conductive hearing loss and offer appropriate habilitative services. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  17. Quadruple cancer including Bowen's disease after arsenic injections 40 years earlier: report of a case.

    PubMed

    Murata, K; Iwazawa, T; Takayama, T; Yamashita, K; Okagawa, K

    1994-01-01

    This report describes the successful treatment of quadruple cancer including Bowen's disease in a 71-year-old man who had been given injections of salvarsan, an arsenic compound, for syphilis more than 40 years earlier. Resection of a skin lesion on his chest subsequently confirmed a diagnosis of Bowen's disease, 3 years after which he was operated on for concurrent gastric cancer and sigmoid colon cancer. A fourth cancer was discovered on his left vocal cord 2 weeks after this operation; it was resected 2 years later. A discussion of multiple malignant neoplasms and the possible relationship between arsenic and cancer is presented following this case report.

  18. Conductivity study of thermally stabilized RuO2/polythiophene nanocomposites

    NASA Astrophysics Data System (ADS)

    Hebbar, Vidyashree; Bhajantri, R. F.

    2018-04-01

    The polymer nanocomposites of Ruthenium oxide (RuO2) filled polythiophene (PT) were synthesized by polymerization using chemical method. The purity of the synthesized polymer composite is verified using X-Ray diffraction (XRD). The structural discrepancies of the RuO2 filled PT composites are studied by Fourier transform infrared (FT-IR) spectroscopy. The phase transition and thermal stability of the prepared composite is revised by thermal characterization such as differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The DC conductivity of RuO2 filled PT composite in the form of pellets is calculated using current-voltage (I-V) characterization by two-probe method. The enhancement in conductivity with increased RuO2 content in PT matrix is examined, which is the required property for electrical and electronic applications in supercapacitors.

  19. Using diurnal streamflow and conductivity data to monitor and forecast runoff in a snowmelt dominated watershed

    NASA Astrophysics Data System (ADS)

    Miller, S.; Miller, S. N.

    2016-12-01

    Natural diurnal fluctuations in streamflow are common in many types of streams and scales for different reasons (i.e. snowmelt, evapotranspiration, infiltration, precipitation). Scientific literature has placed little consideration on the role diurnal cycles as they may appear insignificant from a water management point of view; however, recent insights into the timing and shape of the diurnal cycle have led to new methods for eco-hydrologic characterization of a given watershed. The diurnal effect is usually not detectible from visual investigation of a stream, but requires a minimum of hourly continuous measurement. In the 1990s the United States Geological Survey began collecting hourly river stage measurements for thousands of stream gauge stations across the US, ushering in new methods of analysis and comparison. A nested watershed study with ten stream gauging stations recording sub-hourly river stage was deployed in a snowmelt-dominated region of the Medicine Bow National Forest in southeastern Wyoming in 2013. In addition, at each stream gauging station sub-hourly conductivity and temperature data was recorded to aid in eco-hydrologic characterization of the different watersheds. Early summer results show asymmetry in the diurnal cycle during snowmelt, with a steeper rising and a flatter falling limb. As snowmelt becomes a less contributing component of streamflow later in the season, the asymmetry shifts to a flatter rising limb and steeper falling limb. Stream conductivity is low during snowmelt and begins to gradually increase as baseflow becomes a larger portion of total streamflow. The study region is recovering from a mountain pine beetle epidemic that peaked in 2008. Prior research suggests the bark beetle epidemic has had little effect on annual streamflow patterns; however, several results show an earlier shift in the day of year in which peak annual streamflow is observed. The diurnal cycle is likely to comprise a larger percentage of daily

  20. Effects of earlier sea ice breakup on survival and population size of polar bears in western Hudson Bay

    USGS Publications Warehouse

    Regehr, E.V.; Lunn, N.J.; Amstrup, Steven C.; Stirling, I.

    2007-01-01

    Some of the most pronounced ecological responses to climatic warming are expected to occur in polar marine regions, where temperature increases have been the greatest and sea ice provides a sensitive mechanism by which climatic conditions affect sympagic (i.e., with ice) species. Population-level effects of climatic change, however, remain difficult to quantify. We used a flexible extension of Cormack-Jolly-Seber capture-recapture models to estimate population size and survival for polar bears (Ursus maritimus), one of the most ice-dependent of Arctic marine mammals. We analyzed data for polar bears captured from 1984 to 2004 along the western coast of Hudson Bay and in the community of Churchill, Manitoba, Canada. The Western Hudson Bay polar bear population declined from 1,194 (95% CI = 1,020-1,368) in 1987 to 935 (95% CI = 794-1,076) in 2004. Total apparent survival of prime-adult polar bears (5-19 yr) was stable for females (0.93; 95% CI = 0.91-0.94) and males (0.90; 95% CI = 0.88-0.91). Survival of juvenile, subadult, and senescent-adult polar bears was correlated with spring sea ice breakup date, which was variable among years and occurred approximately 3 weeks earlier in 2004 than in 1984. We propose that this correlation provides evidence for a causal association between earlier sea ice breakup (due to climatic warming) and decreased polar bear survival. It may also explain why Churchill, like other communities along the western coast of Hudson Bay, has experienced an increase in human-polar bear interactions in recent years. Earlier sea ice breakup may have resulted in a larger number of nutritionally stressed polar bears, which are encroaching on human habitations in search of supplemental food. Because western Hudson Bay is near the southern limit of the species' range, our findings may foreshadow the demographic responses and management challenges that more northerly polar bear populations will experience if climatic warming in the Arctic continues as

  1. Electrical conduction studies in ferric-doped KHSO 4 single crystals

    NASA Astrophysics Data System (ADS)

    Sharon, M.; Kalia, A. K.

    1980-03-01

    Direct-current conductivity of ferric-doped (138, 267, and 490 ppm) single crystals of KHSO 4 has been studied. The mechanism for the dc conduction process is discussed. It is observed that the ferric ion forms a (Fe 3+-two vacancies) complex and the enthaply for its formation is 0.09 ± 0.01 eV. It is proposed that each ferric ion removes two protons from each HSO 4 dimer. The conductivity plot shows the presence of intrinsic and extrinsic regions. It is proposed that in the intrinsic region the dimer of HSO -4 breaks reversibly to form a long-chain monomer-type structure. The conductivity in the KHSO 4 crystal is proposed to be controlled by the rotation of HSO -4 tetrahedra along the axis which contains no hydrogen atom. Isotherm calculation for the trivalent-doped system is applied to this crystal and the results are compared with Co 2+-doped KHSO 4 crystal. The distribution coefficient of ferric ion in the KHSO 4 single crystal is calculated to be 4.5 × 10 -1. Ferric ion causes tapering in the crystal growth habit of KHSO 4 and it is believed to be due to the presence of (Fe 3+-two vacancies) complex. The enthalpy values for the various other processes are as follows: enthalpy for the breakage of HSO -4 dimer ( Hi) = 1.28 ± 0.01 eV; enthalpy for the rotation of HSO -4 tetrahedron ( Hm) = 0.58 ± 0.01 eV.

  2. A model study of tunneling conductance spectra of ferromagnetically ordered manganites

    NASA Astrophysics Data System (ADS)

    Panda, Saswati; Kar, J. K.; Rout, G. C.

    2018-02-01

    We report here the interplay of ferromagnetism (FM) and charge density wave (CDW) in manganese oxide systems through the study of tunneling conductance spectra. The model Hamiltonian consists of strong Heisenberg coupling in core t2g band electrons within mean-field approximation giving rise to ferromagnetism. Ferromagnetism is induced in the itinerant eg electrons due to Kubo-Ohata type double exchange (DE) interaction among the t2g and eg electrons. The charge ordering (CO) present in the eg band giving rise to CDW interaction is considered as the extra-mechanism to explain the colossal magnetoresistance (CMR) property of manganites. The magnetic and CDW order parameters are calculated using Zubarev's Green's function technique and solved self-consistently and numerically. The eg electron density of states (DOS) calculated from the imaginary part of the Green's function explains the experimentally observed tunneling conductance spectra. The DOS graph exhibits a parabolic gap near the Fermi energy as observed in tunneling conductance spectra experiments.

  3. Thermal conductivity model for powdered materials under vacuum based on experimental studies

    NASA Astrophysics Data System (ADS)

    Sakatani, N.; Ogawa, K.; Iijima, Y.; Arakawa, M.; Honda, R.; Tanaka, S.

    2017-01-01

    The thermal conductivity of powdered media is characteristically very low in vacuum, and is effectively dependent on many parameters of their constituent particles and packing structure. Understanding of the heat transfer mechanism within powder layers in vacuum and theoretical modeling of their thermal conductivity are of great importance for several scientific and engineering problems. In this paper, we report the results of systematic thermal conductivity measurements of powdered media of varied particle size, porosity, and temperature under vacuum using glass beads as a model material. Based on the obtained experimental data, we investigated the heat transfer mechanism in powdered media in detail, and constructed a new theoretical thermal conductivity model for the vacuum condition. This model enables an absolute thermal conductivity to be calculated for a powder with the input of a set of powder parameters including particle size, porosity, temperature, and compressional stress or gravity, and vice versa. Our model is expected to be a competent tool for several scientific and engineering fields of study related to powders, such as the thermal infrared observation of air-less planetary bodies, thermal evolution of planetesimals, and performance of thermal insulators and heat storage powders.

  4. Conductivity studies of Chitosan doped with different ammonium salts: Effect of ion size

    NASA Astrophysics Data System (ADS)

    Mohan, C. Raja; Senthilkumar, M.; Jayakumar, K.

    2015-06-01

    In the present investigation influence of ion size on the electrical properties of various ammonium salts of various concentrations doped with Chitosan liquid electrolyte has been studied. The attachment of ammonium salts with Chitosan has been confirmed through FTIR Spectrum. Polarizability is calculated from the refractive index data. Addition of ammonium salts increases the conductivity. It is also observed that increase in ion size, increases the ionic conductivity due to increase in amorphous nature of the material. Increase in concentration leads to increase in conductivity due to the presence of more number of free ions.

  5. Study of the variation of thermal conductivity with water saturation using nuclear magnetic resonance

    NASA Astrophysics Data System (ADS)

    Jorand, Rachel; Fehr, Annick; Koch, Andreas; Clauser, Christoph

    2011-08-01

    In this paper, we present a method that allows one to correct thermal conductivity measurements for the effect of water loss when extrapolating laboratory data to in situ conditions. The water loss in shales and unconsolidated rocks is a serious problem that can introduce errors in the characterization of reservoirs. For this study, we measure the thermal conductivity of four sandstones with and without clay minerals according to different water saturation levels using an optical scanner. Thermal conductivity does not decrease linearly with water saturation. At high saturation and very low saturation, thermal conductivity decreases more quickly because of spontaneous liquid displacement and capillarity effects. Apart from these two effects, thermal conductivity decreases quasi-linearly. We also notice that the samples containing clay minerals are not completely drained, and thermal conductivity reaches a minimum value. In order to fit the variation of thermal conductivity with the water saturation as a whole, we used modified models commonly presented in thermal conductivity studies: harmonic and arithmetic mean and geometric models. These models take into account different types of porosity, especially those attributable to the abundance of clay, using measurements obtained from nuclear magnetic resonance (NMR). For argillaceous sandstones, a modified arithmetic-harmonic model fits the data best. For clean quartz sandstones under low water saturation, the closest fit to the data is obtained with the modified arithmetic-harmonic model, while for high water saturation, a modified geometric mean model proves to be the best.

  6. Prevalence of attention-deficit/hyperactivity disorder and conduct disorder among substance abusers.

    PubMed

    Schubiner, H; Tzelepis, A; Milberger, S; Lockhart, N; Kruger, M; Kelley, B J; Schoener, E P

    2000-04-01

    This cross-sectional study sought to determine the prevalence of attention-deficit/hyperactivity disorder (ADHD) and conduct disorder among adults admitted to 2 chemical dependency treatment centers. It was hypothesized that ADHD alone or in combination with conduct disorder would be overrepresented in a population of patients with psychoactive substance use disorders. Two hundred one participants were selected randomly from 2 chemical dependency treatment centers. Standardized clinical interviews were conducted using the Structured Clinical Interview for DSM-IV, the Addiction Severity Index, and DSM-IV criteria for ADHD. Reliabilities for the diagnostic categories were established using the Cohen kappa, and the subgroups of individuals with and without ADHD and conduct disorder were compared. Forty-eight (24%) of the participants were found to meet DSM-IV criteria for ADHD. The prevalence of ADHD was 28% in men (30/106) and 19% in women (18/95; NS). Seventy-nine participants (39%) met criteria for conduct disorder, and 34 of these individuals also had ADHD. Overall, individuals with ADHD (compared with those without ADHD) were more likely to have had more motor vehicle accidents. Women with ADHD (in comparison with women without ADHD) had a higher number of treatments for alcohol abuse. Individuals with conduct disorder (in comparison with those without conduct disorder) were younger, had a greater number of jobs as adults, and were more likely to repeat a grade in school, have a learning disability, be suspended or expelled from school, have an earlier age at onset of alcohol dependence, and have had a greater number of treatments for drug abuse. They were more likely to have a lifetime history of abuse of and/or dependence on cocaine, stimulants, hallucinogens, and/or cannabis. A significant overrepresentation of ADHD exists among inpatients with psychoactive substance use disorders. Over two thirds of those with ADHD in this sample also met criteria for conduct

  7. The Sooner, the Worse? Association between Earlier Age of Sexual Initiation and Worse Adolescent Health and Well-being Outcomes

    PubMed Central

    Osorio, Alfonso; Lopez-del Burgo, Cristina; Carlos, Silvia; de Irala, Jokin

    2017-01-01

    This cross-sectional study assesses the association between age of sexual initiation during adolescence and a selection of well-being outcomes regarding that first relationship. High-school adolescents from El Salvador (2,686) and from Peru (3,399) replied to a paper-pencil questionnaire. Those who were sexually initiated replied to several questions regarding their age at sexual initiation, condom use, satisfaction and reasons/circumstances for that sexual relationship. Approximately 19% of participants were sexually initiated (n = 1,179). After retaining participants with valid responses and with sexual initiation ages between 13 and 17, the final sample for this paper consisted of 996 sexually initiated participants (526 Salvadorians and 470 Peruvians). Multiple logistic regression analyses showed that those who initiated sex at earlier ages had worse outcomes compared to those who initiated at older ages. Specifically, they had lower odds of having used a condom, of having good memories of that experience and of having had that first relationship because they were in love. Conversely, they had higher odds of having had that first sexual relationship as a result of peer pressure (“Most of my friends already had sex”), because of partner pressure (“I was afraid to lose him/her,” “My partner told me he/she would leave me” or “I did not know how to say no to a person who insisted”), or as a consequence of different forms of impaired autonomy (“I was under the influence of alcohol or drugs” or “As a consequence of seeing sexual images”). Results show that sex at earlier ages is associated with worse adolescent health and well-being outcomes. PMID:28798715

  8. Transcriptional analysis of micronutrient zinc-associated response for enhanced carbohydrate utilization and earlier solventogenesis in Clostridium acetobutylicum.

    PubMed

    Wu, You-Duo; Xue, Chuang; Chen, Li-Jie; Wan, Hui-Hui; Bai, Feng-Wu

    2015-11-20

    The micronutrient zinc plays vital roles in ABE fermentation by Clostridium acetobutylicum. In order to elucidate the zinc-associated response for enhanced glucose utilization and earlier solventogenesis, transcriptional analysis was performed on cells grown in glucose medium at the exponential growth phase of 16 h without/with supplementary zinc. Correspondingly, the gene glcG (CAC0570) encoding a glucose-specific PTS was significantly upregulated accompanied with the other two genes CAC1353 and CAC1354 for glucose transport in the presence of zinc. Additionally, genes involved in the metabolisms of six other carbohydrates (maltose, cellobiose, fructose, mannose, xylose and arabinose) were differentially expressed, indicating that the regulatory effect of micronutrient zinc is carbohydrate-specific with respects to the improved/inhibited carbohydrate utilization. More importantly, multiple genes responsible for glycolysis (glcK and pykA), acidogenesis (thlA, crt, etfA, etfB and bcd) and solventogenesis (ctfB and bdhA) of C. acetobutylicum prominently responded to the supplementary zinc at differential expression levels. Comparative analysis of intracellular metabolites revealed that the branch node intermediates such as acetyl-CoA, acetoacetyl-CoA, butyl-CoA, and reducing power NADH remained relatively lower whereas more ATP was generated due to enhanced glycolysis pathway and earlier initiation of solventogenesis, suggesting that the micronutrient zinc-associated response for the selected intracellular metabolisms is significantly pleiotropic.

  9. Alternating current conduction studies on polypyrrole-iron nanocomposite at room temperature

    NASA Astrophysics Data System (ADS)

    Kumar, T. G. Naveen; Megha, R.; Revanasiddappa, M.; Ravikiran, Y. T.; Kumari, S. C. Vijaya

    2018-05-01

    In the present work, Polypyrrole (PPy) and Polypyrrole-Iron (PPy-Fe) nanocomposite were synthesized separately by chemical polymerisation method and then they were structurally characterised by Fourier transform infrared spectroscopy (FTIR) and Transmission electron microscopy (TEM) techniques. The alternate current (AC) response characteristics at room temperature of PPy and the composite were comparatively studied in the frequency range 100Hz-1MHz. The real part of conductivities of both PPy and the composite were interpreted as power law of frequency and the frequency exponent s was found to lie in the range 0< s<1 in both the cases. The nanocomposite has shown significant improvement in conductivity as compared to PPy.

  10. In Situ Study of Strain-Dependent Ion Conductivity of Stretchable Polyethylene Oxide Electrolyte

    PubMed Central

    Kelly, Taylor; Ghadi, Bahar Moradi; Berg, Sean; Ardebili, Haleh

    2016-01-01

    There is a strong need in developing stretchable batteries that can accommodate stretchable or irregularly shaped applications including medical implants, wearable devices and stretchable electronics. Stretchable solid polymer electrolytes are ideal candidates for creating fully stretchable lithium ion batteries mainly due to their mechanical and electrochemical stability, thin-film manufacturability and enhanced safety. However, the characteristics of ion conductivity of polymer electrolytes during tensile deformation are not well understood. Here, we investigate the effects of tensile strain on the ion conductivity of thin-film polyethylene oxide (PEO) through an in situ study. The results of this investigation demonstrate that both in-plane and through-plane ion conductivities of PEO undergo steady and linear growths with respect to the tensile strain. The coefficients of strain-dependent ion conductivity enhancement (CSDICE) for in-plane and through-plane conduction were found to be 28.5 and 27.2, respectively. Tensile stress-strain curves and polarization light microscopy (PLM) of the polymer electrolyte film reveal critical insights on the microstructural transformation of stretched PEO and the potential consequences on ionic conductivity. PMID:26831948

  11. Thermal Conductivity of Twisted Bilayer Graphene Nanoribbons from Non-equilibrium Molecular Dynamics Study.

    NASA Astrophysics Data System (ADS)

    Li, Chenyang; Su, Shanshan; Ge, Supeng; Lake, Roger

    Misorientation of the two layers of bilayer graphene affects both the electronic properties and the vibrational modes or phonons. The phonon density of modes is little affected by misorientation, however, zone-folding can allow new Umklapp scattering processes that could affect the phonon transport and thermal conductivity. To investigate this, we use NEMD molecular dynamics simulations as implemented in LAMMPS to study the thermal conductivity of the misoriented graphene bilayers. Seven commensurate misorientation angles varying from 6.01º to 48.36º have modeled and analyzed to understand how the misorientation angle affects the thermal conductivity of relatively wide ( 10 nm) misoriented bilayer graphene nanoribbons (m-BLGNRs). Within numerical accuracy, we find that the thermal conductivity of the m-BLGNRs for all of the simulated commensurate angles have the same thermal conductivity with AB stacked and AA stacked BLGNRs. These results indicate that neither the misorientation angle nor the stacking order affect the thermal conductivity of BLGNRs. This work was supported as part by the NSF #1307671.

  12. Racial and Regional Differences in Age at Menopause in the United States: Findings from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

    PubMed Central

    Mcknight, Katherine K.; Wellons, Melissa F.; Sites, Cynthia K.; Roth, David L.; Szychowski, Jeff M.; Halanych, Jewell H.; Cushman, Mary; Safford, Monika M.

    2011-01-01

    Objectives To examine regional and Black-White differences in mean age at self-reported menopause among community-dwelling women in the US. Study Design Cross-sectional survey conducted in the context of the REasons for Geographic And Racial Differences in Stroke and Myocardial Infarction study. Results We studied 22,484 menopausal women. After controlling for covariates, Southern women reported menopause 10.8 months earlier than Northeastern women, 8.4 months earlier than Midwestern women, and 6.0 months earlier than Western women (p<0.05 for all). No difference was observed in menopausal age between Black and White women after controlling for covariates (p=0.69). Conclusions Women in the South report earlier menopause than those in other regions, but the cause remains unclear. Our study's large sample size and adjustment for multiple confounders lends weight to our finding of no racial difference in age at menopause. More study is needed of the implications of these findings with regard to vascular health. PMID:21663888

  13. The characteristics of national health initiatives promoting earlier cancer diagnosis among adult populations: a systematic review protocol

    PubMed Central

    Calanzani, Natalia; Weller, David; Campbell, Christine

    2017-01-01

    Introduction The increasing burden of cancer morbidity and mortality has led to the development of national health initiatives to promote earlier cancer diagnosis and improve cancer survival. This protocol describes a systematic review aiming to identify the evidence about such initiatives among the adult population. We will describe their components, stakeholders and target populations, and summarise their outcomes. Methods and analysis We will search databases and websites for peer-reviewed publications and grey literature on national health initiatives in high-income countries as defined by the World Bank. Quantitative, qualitative and mixed-methods studies will be included and assessed for their methodological quality. Study selection, quality assessment and data extraction will be carried out independently by two reviewers. Narrative synthesis will be used to analyse the findings. Ethics and dissemination This systematic review analyses secondary data and ethical approval is not required. Review findings will be helpful to researchers, policy makers, governments and other key stakeholders developing similar initiatives and assessing cancer outcomes. The results will be submitted to a peer-reviewed journal in order to reach a diverse group of healthcare professionals, researchers and policy makers. This systematic review protocol is registered at PROSPERO (CRD42016047233). PMID:28698336

  14. A flux-limited treatment for the conductive evaporation of spherical interstellar gas clouds

    NASA Technical Reports Server (NTRS)

    Dalton, William W.; Balbus, Steven A.

    1993-01-01

    In this work, we present and analyze a new analytic solution for the saturated (flux-limited) thermal evaporation of a spherical cloud. This work is distinguished from earlier analytic studies by allowing the thermal conductivity to change continuously from a diffusive to a saturated form, in a manner usually employed only in numerical calculations. This closed form solution will be of interest as a computational benchmark. Using our calculated temperature profiles and mass-loss rates, we model the thermal evaporation of such a cloud under typical interstellar medium (ISM) conditions, with some restrictions. We examine the ionization structure of the cloud-ISM interface and evaluate column densities of carbon, nitrogen, oxygen, neon, and silicon ions toward the cloud. In accord with other investigations, we find that ionization equilibrium is far from satisfied under the assumed conditions. Since the inclusion of saturation effects in the heat flux narrows the thermal interface relative to its classical structure, we also find that saturation effects tend to lower predicted column densities.

  15. USING CONTINUOUS MONITORS FOR CONDUCTING TRACER STUDIES IN WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    The use of online monitors for conducting a distribution system tracer study is proving to be an essential tool to accurately understand the flow dynamics in a distribution system. In a series of field testing sponsored by U. S. Environmental Protection Agency (EPA) and Greater ...

  16. Electrical conductivity enhancement by boron-doping in diamond using first principle calculations

    NASA Astrophysics Data System (ADS)

    Ullah, Mahtab; Ahmed, Ejaz; Hussain, Fayyaz; Rana, Anwar Manzoor; Raza, Rizwan

    2015-04-01

    Boron doping in diamond plays a vital role in enhancing electrical conductivity of diamond by making it a semiconductor, a conductor or even a superconductor. To elucidate this fact, partial and total density of states has been determined as a function of B-content in diamond. Moreover, the orbital charge distributions, B-C bond lengths and their population have been studied for B-doping in pristine diamond thin films by applying density functional theory (DFT). These parameters have been found to be influenced by the addition of different percentages of boron atoms in diamond. The electronic density of states, B-C bond situations as well as variations in electrical conductivities of diamond films with different boron content and determination of some relationship between these parameters were the basic tasks of this study. Diamond with high boron concentration (∼5.88% B-atoms) showed maximum splitting of energy bands (caused by acceptor impurity states) at the Fermi level which resulted in the enhancement of electron/ion conductivities. Because B atoms either substitute carbon atoms and/or assemble at grain boundaries (interstitial sites) inducing impurity levels close to the top of the valence band. At very high B-concentration, impurity states combine to form an impurity band which accesses the top of the valence band yielding metal like conductivity. Moreover, bond length and charge distributions are found to decrease with increase in boron percentage in diamond. It is noted that charge distribution decreased from +1.89 to -1.90 eV whereas bond length reduced by 0.04 Å with increasing boron content in diamond films. These theoretical results support our earlier experimental findings on B-doped diamond polycrystalline films which depict that the addition of boron atoms to diamond films gives a sudden fall in resistivity even up to 105 Ω cm making it a good semiconductor for its applications in electrical devices.

  17. Study of dielectric relaxation and AC conductivity of InP:S single crystal

    NASA Astrophysics Data System (ADS)

    El-Nahass, M. M.; Ali, H. A. M.; El-Shazly, E. A.

    2012-07-01

    The dielectric relaxation and AC conductivity of InP:S single crystal were studied in the frequency range from 100 to 5.25 × 105 Hz and in the temperature range from 296 to 455 K. The dependence of the dielectric constant (ɛ1) and the dielectric loss (ɛ2) on both frequency and temperature was investigated. Since no peak was observed on the dielectric loss, we used a method based on the electric modulus to evaluate the activation energy of the dielectric relaxation. Scaling of the electric modulus spectra showed that the charge transport dynamics is independent of temperature. The AC conductivity (σAC) was found to obey the power law: Aωs. Analysis of the AC conductivity data and the frequency exponent showed that the correlated barrier hopping (CBH) model is the dominant mechanism for the AC conduction. The variation of AC conductivity with temperature at different frequencies showed that σAC is a thermally activated process.

  18. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Conduct of health assessments and health effects studies. 90.8 Section 90.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES...

  19. Thermal conductivity at the nanoscale: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Lyver, John W., IV

    With the growing use of nanotechnology and nanodevices in many fields of engineering and science, a need for understanding the thermal properties of such devices has increased. The ability for nanomaterials to conduct heat is highly dependent on the purity of the material, internal boundaries due to material changes and the structure of the material itself. Experimentally measuring the heat transport at the nanoscale is extremely difficult and can only be done as a macro output from the device. Computational methods such as various Monte Carlo (MC) and molecular dynamics (MD) techniques for studying the contribution of atomic vibrations associated with heat transport properties are very useful. The Green--Kubo method in conjunction with Fourier's law for calculating the thermal conductivity, kappa, has been used in this study and has shown promise as one approach well adapted for understanding nanosystems. Investigations were made of the thermal conductivity using noble gases, modeled with Lennard-Jones (LJ) interactions, in solid face-centered cubic (FCC) structures. MC and MD simulations were done to study homogeneous monatomic and binary materials as well as slabs of these materials possessing internal boundaries. Additionally, MD simulations were done on silicon carbide nanowires, nanotubes, and nanofilaments using a potential containing two-body and three-body terms. The results of the MC and MD simulations were matched against available experimental and other simulations and showed that both methods can accurately simulate real materials in a fraction of the time and effort. The results of the study show that in compositionally disordered materials the selection of atomic components by their mass, hard-core atomic diameter, well depth, and relative concentration can change the kappa by as much as an order of magnitude. It was found that a 60% increase in mass produces a 25% decrease in kappa. A 50% increase in interatomic strength produces a 25% increase in

  20. Interpreting equilibrium-conductivity and conductivity-relaxation measurements to establish thermodynamic and transport properties for multiple charged defect conducting ceramics.

    PubMed

    Zhu, Huayang; Ricote, Sandrine; Coors, W Grover; Kee, Robert J

    2015-01-01

    A model-based interpretation of measured equilibrium conductivity and conductivity relaxation is developed to establish thermodynamic, transport, and kinetics parameters for multiple charged defect conducting (MCDC) ceramic materials. The present study focuses on 10% yttrium-doped barium zirconate (BZY10). In principle, using the Nernst-Einstein relationship, equilibrium conductivity measurements are sufficient to establish thermodynamic and transport properties. However, in practice it is difficult to establish unique sets of properties using equilibrium conductivity alone. Combining equilibrium and conductivity-relaxation measurements serves to significantly improve the quantitative fidelity of the derived material properties. The models are developed using a Nernst-Planck-Poisson (NPP) formulation, which enables the quantitative representation of conductivity relaxations caused by very large changes in oxygen partial pressure.

  1. Attachment styles, earlier interpersonal relationships and schizotypy in a non-clinical sample.

    PubMed

    Berry, Katherine; Band, Rebecca; Corcoran, Rhiannon; Barrowclough, Christine; Wearden, Alison

    2007-12-01

    This paper investigates associations between adult attachment style, relationships with significant others during childhood, traumatic life-events and schizotypy. Relationships between attachment and hypothesized correlates were investigated in a cross-sectional design using an analogue sample. The reliability of the attachment and trauma measures was investigated using a test-retest design. Three hundred and four students completed the self-report version of the Psychosis Attachment Measure (PAM), maternal and paternal versions of the Parental Bonding Instrument, the Attachment History Questionnaire, a measure of trauma and the Oxford-Liverpool Inventory of Feelings and Experiences scale through an internet website. As predicted, there were statistically significant associations between insecure attachment in adult relationships and experiences of negative interpersonal events. Both earlier interpersonal experiences and adult attachment style predicted schizotypy, and adult attachment style emerged as an independent predictor of positive schizotypal characteristics. The findings support associations between adult attachment style and previous interpersonal experiences and between adult attachment and schizotypy. The PAM is a reliable and valid instrument that can be used to explore attachment styles in analogue samples and associations between attachment styles and psychotic symptoms in clinical samples.

  2. Significance of Childhood Conduct Problems to Later Development of Conduct Disorder among Children with ADHD: A Prospective Follow-Up Study

    ERIC Educational Resources Information Center

    Mannuzza, Salvatore; Klein, Rachel G.; Abikoff, Howard; Moulton, John L., III

    2004-01-01

    This study investigates whether low to moderate levels of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) behaviors contribute to the development of clinically diagnosed CD in adolescence, in children with attention deficit hyperactivity disorder (ADHD). Participants were 207 White boys (ages 6-12) with ADHD free of conduct…

  3. Thermal conductivity and thermal rectification in graphene nanoribbons: a molecular dynamics study.

    PubMed

    Hu, Jiuning; Ruan, Xiulin; Chen, Yong P

    2009-07-01

    We have used molecular dynamics to calculate the thermal conductivity of symmetric and asymmetric graphene nanoribbons (GNRs) of several nanometers in size (up to approximately 4 nm wide and approximately 10 nm long). For symmetric nanoribbons, the calculated thermal conductivity (e.g., approximately 2000 W/m-K at 400 K for a 1.5 nm x 5.7 nm zigzag GNR) is on the similar order of magnitude of the experimentally measured value for graphene. We have investigated the effects of edge chirality and found that nanoribbons with zigzag edges have appreciably larger thermal conductivity than nanoribbons with armchair edges. For asymmetric nanoribbons, we have found significant thermal rectification. Among various triangularly shaped GNRs we investigated, the GNR with armchair bottom edge and a vertex angle of 30 degrees gives the maximal thermal rectification. We also studied the effect of defects and found that vacancies and edge roughness in the nanoribbons can significantly decrease the thermal conductivity. However, substantial thermal rectification is observed even in the presence of edge roughness.

  4. XPAT: a toolkit to conduct cross-platform association studies with heterogeneous sequencing datasets.

    PubMed

    Yu, Yao; Hu, Hao; Bohlender, Ryan J; Hu, Fulan; Chen, Jiun-Sheng; Holt, Carson; Fowler, Jerry; Guthery, Stephen L; Scheet, Paul; Hildebrandt, Michelle A T; Yandell, Mark; Huff, Chad D

    2018-04-06

    High-throughput sequencing data are increasingly being made available to the research community for secondary analyses, providing new opportunities for large-scale association studies. However, heterogeneity in target capture and sequencing technologies often introduce strong technological stratification biases that overwhelm subtle signals of association in studies of complex traits. Here, we introduce the Cross-Platform Association Toolkit, XPAT, which provides a suite of tools designed to support and conduct large-scale association studies with heterogeneous sequencing datasets. XPAT includes tools to support cross-platform aware variant calling, quality control filtering, gene-based association testing and rare variant effect size estimation. To evaluate the performance of XPAT, we conducted case-control association studies for three diseases, including 783 breast cancer cases, 272 ovarian cancer cases, 205 Crohn disease cases and 3507 shared controls (including 1722 females) using sequencing data from multiple sources. XPAT greatly reduced Type I error inflation in the case-control analyses, while replicating many previously identified disease-gene associations. We also show that association tests conducted with XPAT using cross-platform data have comparable performance to tests using matched platform data. XPAT enables new association studies that combine existing sequencing datasets to identify genetic loci associated with common diseases and other complex traits.

  5. What do they know about Heat and Heat Conduction? A case study to excavate Pre-service Physics Teachers’ Mental Model in Heat and Heat Conduction

    NASA Astrophysics Data System (ADS)

    Sari, I. M.

    2017-02-01

    Teacher plays a crucial role in Education. Helping students construct scientifically mental model is one of obligation of Physics Education Department of Teacher Education Institute that produce physics teacher. Excavating students’ mental model is necessary to be done in physics education. This research was first to identify 23 physics students’ mental model of heat and heat conduction. A series of semi-structured interviews was conducted to excavate the students’ understanding of heat and mental models on heat conduction. The students who involved in this study come from different level from sophomore to master degree in Physics Education Department. This study adopted a constant comparison method to obtain the patterns of the participants’ responses through the students’ writing, drawing and verbal utterances. The framework for assessing mental model and the instruments were adopted and adapted from Chiou and Anderson (2010). We also compared the students’ understanding of heat and mental models on heat conduction. The result shows that Heat is treated as Intrinsic property, material substances, and caloric flow. None of students expressed heat as transfer of thermal energy. Moreover, there are two kinds of students’ fundamental component of mental model in heat conduction were found: medium and molecules. Students understanding of heat and fundamental components of mental model in heat conduction are not resulted from running mental model.

  6. [Collaboration between science and practice: experiences of conducting a nursing intervention study].

    PubMed

    Panfil, Eva-Maria; Kirchner, Elisabeth; Bauder-Missbach, Heidi; Haasenritter, Jörg; Eisenschink, Anna Maria

    2009-09-01

    In a five-year intervention study about the impact of pre-operative mobilisation training session of patients receiving an elective medial laparotomy experiences about the collaboration between practice (University Hospital Ulm) and science (Hessian Institute of Nursing Research) were made. During the project possibilities and borders of clinical nursing research became clear. A research question based on practice experiences of nurses helps to develop and maintain motivation to conduct a study at a nursing unit. There was a lack of nursing knowledge to develop the best possible design, e.g. outcome criteria for mobilisation and standardized assessment instruments. The cooperation with other health care professionals (human movement science, statistics) was important and without difficulties. In Germany, without doctors' agreement and common application it is impossible to conduct nursing intervention studies in hospitals. It is necessary to train nursing specialists with both scientific and clinical competence to explore systematically clinical research questions.

  7. Earlier onset of motor deficits in mice with double mutations in Dyt1 and Sgce.

    PubMed

    Yokoi, Fumiaki; Yang, Guang; Li, Jindong; DeAndrade, Mark P; Zhou, Tong; Li, Yuqing

    2010-10-01

    DYT1 early-onset generalized torsion dystonia is an inherited movement disorder caused by mutations in DYT1 coding for torsinA with ∼30% penetrance. Most of the DYT1 dystonia patients exhibit symptoms during childhood and adolescence. On the other hand, DYT1 mutation carriers without symptoms during these periods mostly do not exhibit symptoms later in their life. Little is known about what controls the timing of the onset, a critical issue for DYT1 mutation carriers. DYT11 myoclonus-dystonia is caused by mutations in SGCE coding for ε-sarcoglycan. Two dystonia patients from a single family with double mutations in DYT1 and SGCE exhibited more severe symptoms. A recent study suggested that torsinA contributes to the quality control of ε-sarcoglycan. Here, we derived mice carrying mutations in both Dyt1 and Sgce and found that these double mutant mice showed earlier onset of motor deficits in beam-walking test. A novel monoclonal antibody against mouse ε-sarcoglycan was developed by using Sgce knock-out mice to avoid the immune tolerance. Western blot analysis suggested that functional deficits of torsinA and ε-sarcoglycan may independently cause motor deficits. Examining additional mutations in other dystonia genes may be beneficial to predict the onset in DYT1 mutation carriers.

  8. Generation of Vorticity by Slow Conductive Cooling Flows.

    NASA Astrophysics Data System (ADS)

    Meerson, Baruch; Glasner, Ami; Livne, Eli

    1996-11-01

    Rapid energy release in a gas produces a ``hot channel" or ``fireball", depending on the energy release geometry. During its relaxation, the ``hot channel" develops significant vorticity and turbulence(J.M. Picone, J.P. Boris, J.R. Greig, M. Raleigh, and R.F. Fernsler, J. Atmos. Sci. 38), 2056 (1981). that strongly enhance its cooling. Picone and Boris(J.M. Picone and J.P. Boris, Phys. Fluids 26), 365 (1983). attributed the effect to an earlier, plasma-expansion-related stage of the process. We show that vorticity can also be produced on a longer time scale. After a few acoustic times, the plasma pressure becomes very close to the ambient pressure. As the temperature is still high, slow (subacoustic) conductive cooling flow (CCF) develops that cools the cavity and fills it with gas from the periphery(B. Meerson, Phys. Fluids A 1), 887 (1989); D. Kaganovich, B. Meerson, A. Zigler, C. Cohen, and J. Levin, Phys. Plasmas 3, 631 (1996).. Due to asymmetries, this flow develops significant vorticity on the heat-conduction time scale. We present a simplified theory for this effect that employs, as a zero-order solution, a novel two-dimensional (2d) similarity solution for an irrotational isobaric CCF. We also report on gas-dynamic simulations in 2d (with the heat transfer taken into account) which show vorticity generation by the slow CCF.

  9. Summary Findings of Pilot Studies Conducted by the Interagency Coastal Wetlands Workgroup

    EPA Pesticide Factsheets

    The ICWWG conducted studies in coastal watersheds to better understand coastal wetland loss. Identified drivers, such as development pressure, drainage practices, and insufficient restore wetland acres to offset acres lost. Provides some recommendations.

  10. Conductive tracks of 30-MeV C60 clusters in doped and undoped tetrahedral amorphous carbon

    NASA Astrophysics Data System (ADS)

    Krauser, J.; Gehrke, H.-G.; Hofsäss, H.; Trautmann, C.; Weidinger, A.

    2013-07-01

    In insulating tetrahedral amorphous carbon (ta-C), the irradiation with 30-MeV C60 cluster ions leads to the formation of well conducting tracks. While electrical currents through individual tracks produced with monoatomic projectiles (e.g. Au or U) often exhibit rather large track to track fluctuations, C60 clusters are shown to generate highly conducting tracks with very narrow current distributions. Additionally, all recorded current-voltage curves show linear characteristics. These findings are attributed to the large specific energy loss dE/dx of the 30-MeV C60 clusters. We also investigated C60 tracks in ta-C films which were slightly doped with B, N or Fe during film growth. Doping apparently increases the ion track conductivity. However, at the same time the insulating characteristics of the pristine ta-C film can be reduced. The present C60 results are compared with data from earlier experiments with monoatomic heavy ion beams. The investigations were performed by means of atomic force microscopy including temperature dependent conductivity measurements of single ion tracks.

  11. Does earlier arrival of the retrieval team improve short-term outcomes in outborn extremely premature infants?

    PubMed

    Sharpe, Janet B; Davies, Mark W

    2018-05-31

    The risk of mortality and morbidity is increased in outborn, extremely premature infants. We aim to determine whether earlier arrival of the retrieval team after the birth of infants less than 29 weeks gestation improves short-term mortality and morbidity. This is a retrospective analysis of a cohort of infants less than 29 weeks gestation who were retrieved to the Royal Brisbane and Women's Hospital (RBWH) over a 5-year period. Demographic information regarding the infant and mother, retrieval team arrival time and outcome data was collected. Primary outcomes investigated were mortality prior to discharge from hospital or a composite of mortality or severe intraventricular haemorrhage (IVH). Data on 105 infants were analysed; 88 infants (83.8%) survived to discharge home, and 79 (75.2%) survived to discharge without severe IVH. On univariate analysis, there was no significant association between age at arrival of the retrieval team and death prior to discharge (P = 0.94) or death prior to discharge or severe IVH (P = 0.83). On logistic regression analysis, age at arrival of retrieval team remained non-significant for a reduction in death prior to discharge and composite of death or severe IVH (P = 0.70 and P = 0.99, respectively). The earlier arrival of the retrieval team is not associated with improved short-term outcomes in outborn, extremely preterm infants who are retrieved and admitted to a tertiary neonatal intensive care unit - for infants where the retrieval team arrived within about 8 h of birth. © 2018 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  12. A study on electrode gels for skin conductance measurements.

    PubMed

    Tronstad, Christian; Johnsen, Gorm Krogh; Grimnes, Sverre; Martinsen, Ørjan G

    2010-10-01

    Low-frequency skin conductance is used within several clinical applications and is mainly sensitive to sweating and the moisture content of the stratum corneum, but also how electrodes introduce changes in the electrical properties. Four electrode gels were investigated with regard to sorption characteristics and electrical properties. Skin conductance time series were collected from 18 test subjects during relaxation, exercise and recovery, wearing different pairs of electrodes contralaterally on the hypothenar and the T9 dermatome. Pressure test was applied on the T9 electrodes. Impedance frequency sweeps were taken on the T9 electrodes the same day and the next, parameterized to the Cole model. ANOVA on the initial skin conductance level change, exercise response amplitude, recovery offset and pressure-induced changes revealed significant differences among gel types. The wetter gels caused a higher positive level change, a greater response amplitude, larger recovery offset and greater pressure-induced artifacts compared to the solid gels. Sweating on the T9 site led to negative skin conductance responses for the wetter gels. Correlations were found between the desorption measurements and the initial skin conductance level change (hypothenar: R = 0.988 T9: R = 0.901) RM-ANOVA on the Cole parameters revealed a significant decrease in R(s) of the most resistive gel. Clinical implications are discussed.

  13. Conducting omega-3 clinical trials with cardiovascular outcomes: Proceedings of a workshop held at ISSFAL 2014.

    PubMed

    Rice, Harry B; Bernasconi, Aldo; Maki, Kevin C; Harris, William S; von Schacky, Clemens; Calder, Philip C

    2016-04-01

    In contrast to earlier long-chain (LC) omega-3 (i.e. EPA and DHA) investigations, some recent studies have not demonstrated significant effects of EPA and DHA on cardiovascular disease (CVD) outcomes. The neutral findings may have been due to experimental design issues, such as: maintenance on aggressive cardiovascular drug treatment overshadowing the benefits of LC omega-3s, high background LC omega-3 intake, too few subjects in the study, treatment duration too short, insufficient LC omega-3 dosage, increase in omega-6 fatty acid intake during the study, failure to assess the LC omega-3 status of the subjects prior to and during treatment and lack of clarity concerning which mechanisms were expected to produce benefits. At the 11th ISSFAL Congress, a workshop was held on conducting LC omega-3 clinical trials with cardiovascular outcomes, with the goal of gaining a better understanding concerning aspects of experimental design that should be considered when planning clinical studies related to EPA and DHA and potential cardiovascular benefits. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. A study of the influence of conductive paths and their directions in randomly generated conductor network.

    NASA Astrophysics Data System (ADS)

    Mandolesi, E.; Moorkamp, M.; Jones, A. G.

    2014-12-01

    Most electromagnetic (EM) geophysical methods focus on the electrical conductivity of rocks and sediments to determine the geological structure of the subsurface. Electric conductivity itself is measured in the laboratory with a wide range of instruments and techniques. These measurements seldom return a compatible result. The presence of partially-interconnected random pathways of electrically conductive materials in resistive hosts has been studied for decades, and recently with increasing interest. To comprehend which conductive mechanism scales from the microstructures up to field electrical conductivity measurements, two main branch of studies have been undertaken: statistical probability of having a conductive pathways and mixing laws. Several numerical approaches have been tested to understand the effects of interconnected pathways of conductors at field scale. Usually these studies were restricted in two ways: the sources are considered constant in time (i.e., DC) and the domain is, with few exception, two-dimensional. We simulated the effects of time-varying EM sources on the conductivity measured on the surface of a three-dimensional randomly generated body embedded in an uniform host by using electromagnetic induction equations. We modelled a two-phase mixture of resistive and conductive elements with the goal of comparing the conductivity measured on field scale with the one proper of the elements constituting the random rock, and to test how the internal structures influence the directionality of the responses. Moreover, we modelled data from randomly generated bodies characterized by coherent internal structures, to check the effect of the named structures on the anisotropy of the effective conductivity. We compared these values with the electrical conductivity limits predicted by Hashin-Shtrikman bounds and the effective conductivity predicted by the Archie's law, both cast in its classic form and in an updated that allow to take in account two

  15. Conducting Studies of Transfer of Learning: A Practical Guide. Final Report.

    ERIC Educational Resources Information Center

    Payne, Thomas A.

    This document is a guide for use by the practical researcher concerned with conducting studies of transfer of learning from pretraining of pilots in ground-based environments to performance in aircraft. While the material addresses principally transfer of learning of pilots, many of the issues should be applicable to other contexts, to include…

  16. An inhibitor of polyamine synthesis arrests cells at an earlier stage of G1 than does calcium deprivation.

    PubMed Central

    Cheetham, B F

    1983-01-01

    Methylglyoxal bis(guanylhydrazone) completely inhibits the induction of thymidine kinase after serum stimulation of quiescent fibroblasts only if added within 3 h after serum, whereas calcium deprivation blocks this induction up to 12 h after serum stimulation. Experiments in which one of these blocks was imposed as the other was released confirmed that cells blocked by methylglyoxal bis(guanylhydrazone) are arrested at an earlier stage in G1 than cells blocked by calcium deprivation. PMID:6843551

  17. Studying the influence of substrate conductivity on the optoelectronic properties of quantum dots langmuir monolayer

    NASA Astrophysics Data System (ADS)

    Al-Alwani, Ammar J.; Chumakov, A. S.; Begletsova, N. N.; Shinkarenko, O. A.; Markin, A. V.; Gorbachev, I. A.; Bratashov, D. N.; Gavrikov, M. V.; Venig, S. B.; Glukhovskoy, E. G.

    2018-04-01

    The formation of CdSe quantum dots (QDs) monolayers was studied by Langmuir Blodgett method. The fluorescence (PL) spectra of QD monolayers were investigated at different substrate type (glass, silicon and ITO glass) and the influence of graphene sheets layer (as a conductive surface) on the QDs properties has also been studied. The optoelectronic properties of QDs can be tuned by deposition of insulating nano-size layers of the liquid crystal between QDs and conductive substrate. The monolayer of QDs transferred on conductive surface (glass with ITO) has lowest intensity of PL spectra due to quenching effect. The PL intensity of QDs could be tuned by using various type of substrates or/and by transformed high conductive layer. Also the photooxidation processes of CdSe QDs monolayer on the solid surface can be controlled by selection of suitable substrate. The current-voltage (I–V) characteristics of QDs thin film on ITO surface was studied using scanning tunneling microscope (STM).

  18. Conductivity, dielectric and modulus study of chitosan-methyl cellulose - BMIMTFSI polymer electrolyte doped with cellulose nano crystal

    NASA Astrophysics Data System (ADS)

    Misenan, Muhammad Syukri Mohamad; Ali, Ernie Suzana; Khiar, Azwani Sofia Ahmad

    2018-06-01

    In this study, the effect of adding cellulose nanocrystal (CNC) on the conductivity of biopolymer electrolyte (BPE) based on chitosan-methylcellulose-BMIMTFSI has been studied. The samples were prepared via solution casting technique. The film was characterized by impedance spectroscopy HIOKI 3531- 01 LCR Hi-Tester to measure its ionic conductivity at room temperatures over a wide range of frequency between 50Hz-5MHz. Sample with 15 wt% of CNC shows the highest conductivity of 4.82 x 10-6 Scm-1 at room temperature. Dielectric and modulus studies were carried out to further understands the conductivity behavior of the samples. The increase in conductivity is mainly due to the increase in number of charge carriers.

  19. Genome-wide association study of the age of onset of childhood asthma.

    PubMed

    Forno, Erick; Lasky-Su, Jessica; Himes, Blanca; Howrylak, Judie; Ramsey, Clare; Brehm, John; Klanderman, Barbara; Ziniti, John; Melén, Erik; Pershagen, Goran; Wickman, Magnus; Martinez, Fernando; Mauger, Dave; Sorkness, Christine; Tantisira, Kelan; Raby, Benjamin A; Weiss, Scott T; Celedón, Juan C

    2012-07-01

    Childhood asthma is a complex disease with known heritability and phenotypic diversity. Although an earlier onset has been associated with more severe disease, there has been no genome-wide association study of the age of onset of asthma in children. We sought to identify genetic variants associated with earlier onset of childhood asthma. We conducted the first genome-wide association study of the age of onset of childhood asthma among participants in the Childhood Asthma Management Program (CAMP) and used 3 independent cohorts from North America, Costa Rica, and Sweden for replication. Two single nucleotide polymorphisms (SNPs) were associated with earlier onset of asthma in the combined analysis of CAMP and the replication cohorts: rs9815663 (Fisher P= 2.31 × 10(-8)) and rs7927044 (P= 6.54 × 10(-9)). Of these 2 SNPs, rs9815663 was also significantly associated with earlier asthma onset in an analysis including only the replication cohorts. Ten SNPs in linkage disequilibrium with rs9815663 were also associated with earlier asthma onset (2.24 × 10(-7) earlier onset of childhood asthma in 4 independent cohorts. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  20. Clinical Evidence for the Earlier Initiation of Insulin Therapy in Type 2 Diabetes

    PubMed Central

    2013-01-01

    Abstract The natural history of type 2 diabetes mellitus (T2DM) is a relentless progression of β-cell failure and dysregulation of β-cell function with increasing metabolic derangement. Insulin remains the only glucose-lowering therapy that is efficacious throughout this continuum. However, the timing of introduction and the choice of insulin therapy remain contentious because of the heterogeneity of T2DM and the well-recognized behavioral and therapeutic challenges associated with this mode of therapy. Nevertheless, the early initiation of basal insulin has been shown to improve glycemic control and affect long-term outcomes in people with T2DM and is a treatment strategy supported by international guidelines as part of an individualized approach to chronic disease management. The rationale for early initiation of insulin is based on evidence demonstrating multifaceted benefits, including overcoming the glucotoxic effects of hyperglycemia, thereby facilitating “β-cell rest,” and preserving β-cell mass and function, while also improving insulin sensitivity. Independent of its effects on glycemic control, insulin possesses anti-inflammatory and antioxidant properties that may help protect against endothelial dysfunction and damage resulting in vascular disease. Insulin therapy and the achievement of good glycemic control earlier in T2DM provide long-term protection to end organs via “metabolic memory” regardless of subsequent treatments and degree of glycemic control. This is evidenced from long-term observations continuing from trials such as the United Kingdom Prospective Diabetes Study. As such, early initiation of insulin therapy may not only help to avoid the effects of prolonged glycemic burden, but may also positively alter the course of disease progression. PMID:23786228

  1. Comparing the similarity of responses received from studies in Amazon's Mechanical Turk to studies conducted online and with direct recruitment.

    PubMed

    Bartneck, Christoph; Duenser, Andreas; Moltchanova, Elena; Zawieska, Karolina

    2015-01-01

    Computer and internet based questionnaires have become a standard tool in Human-Computer Interaction research and other related fields, such as psychology and sociology. Amazon's Mechanical Turk (AMT) service is a new method of recruiting participants and conducting certain types of experiments. This study compares whether participants recruited through AMT give different responses than participants recruited through an online forum or recruited directly on a university campus. Moreover, we compare whether a study conducted within AMT results in different responses compared to a study for which participants are recruited through AMT but which is conducted using an external online questionnaire service. The results of this study show that there is a statistical difference between results obtained from participants recruited through AMT compared to the results from the participant recruited on campus or through online forums. We do, however, argue that this difference is so small that it has no practical consequence. There was no significant difference between running the study within AMT compared to running it with an online questionnaire service. There was no significant difference between results obtained directly from within AMT compared to results obtained in the campus and online forum condition. This may suggest that AMT is a viable and economical option for recruiting participants and for conducting studies as setting up and running a study with AMT generally requires less effort and time compared to other frequently used methods. We discuss our findings as well as limitations of using AMT for empirical studies.

  2. Thermal conductivity of catalyst layer of polymer electrolyte membrane fuel cells: Part 1 - Experimental study

    NASA Astrophysics Data System (ADS)

    Ahadi, Mohammad; Tam, Mickey; Saha, Madhu S.; Stumper, Jürgen; Bahrami, Majid

    2017-06-01

    In this work, a new methodology is proposed for measuring the through-plane thermal conductivity of catalyst layers (CLs) in polymer electrolyte membrane fuel cells. The proposed methodology is based on deconvolution of bulk thermal conductivity of a CL from measurements of two thicknesses of the CL, where the CLs are sandwiched in a stack made of two catalyst-coated substrates. Effects of hot-pressing, compression, measurement method, and substrate on the through-plane thermal conductivity of the CL are studied. For this purpose, different thicknesses of catalyst are coated on ethylene tetrafluoroethylene (ETFE) and aluminum (Al) substrates by a conventional Mayer bar coater and measured by scanning electron microscopy (SEM). The through-plane thermal conductivity of the CLs is measured by the well-known guarded heat flow (GHF) method as well as a recently developed transient plane source (TPS) method for thin films which modifies the original TPS thin film method. Measurements show that none of the studied factors has any effect on the through-plane thermal conductivity of the CL. GHF measurements of a non-hot-pressed CL on Al yield thermal conductivity of 0.214 ± 0.005 Wṡm-1ṡK-1, and TPS measurements of a hot-pressed CL on ETFE yield thermal conductivity of 0.218 ± 0.005 Wṡm-1ṡK-1.

  3. Analysis of arrhythmic events is useful to detect lead failure earlier in patients followed by remote monitoring.

    PubMed

    Nishii, Nobuhiro; Miyoshi, Akihito; Kubo, Motoki; Miyamoto, Masakazu; Morimoto, Yoshimasa; Kawada, Satoshi; Nakagawa, Koji; Watanabe, Atsuyuki; Nakamura, Kazufumi; Morita, Hiroshi; Ito, Hiroshi

    2018-03-01

    Remote monitoring (RM) has been advocated as the new standard of care for patients with cardiovascular implantable electronic devices (CIEDs). RM has allowed the early detection of adverse clinical events, such as arrhythmia, lead failure, and battery depletion. However, lead failure was often identified only by arrhythmic events, but not impedance abnormalities. To compare the usefulness of arrhythmic events with conventional impedance abnormalities for identifying lead failure in CIED patients followed by RM. CIED patients in 12 hospitals have been followed by the RM center in Okayama University Hospital. All transmitted data have been analyzed and summarized. From April 2009 to March 2016, 1,873 patients have been followed by the RM center. During the mean follow-up period of 775 days, 42 lead failure events (atrial lead 22, right ventricular pacemaker lead 5, implantable cardioverter defibrillator [ICD] lead 15) were detected. The proportion of lead failures detected only by arrhythmic events, which were not detected by conventional impedance abnormalities, was significantly higher than that detected by impedance abnormalities (arrhythmic event 76.2%, 95% CI: 60.5-87.9%; impedance abnormalities 23.8%, 95% CI: 12.1-39.5%). Twenty-seven events (64.7%) were detected without any alert. Of 15 patients with ICD lead failure, none has experienced inappropriate therapy. RM can detect lead failure earlier, before clinical adverse events. However, CIEDs often diagnose lead failure as just arrhythmic events without any warning. Thus, to detect lead failure earlier, careful human analysis of arrhythmic events is useful. © 2017 Wiley Periodicals, Inc.

  4. Theoretical study of optical conductivity of graphene with magnetic and nonmagnetic adatoms

    NASA Astrophysics Data System (ADS)

    Majidi, Muhammad Aziz; Siregar, Syahril; Rusydi, Andrivo

    2014-11-01

    We present a theoretical study of the optical conductivity of graphene with magnetic and nonmagnetic adatoms. First, by introducing an alternating potential in a pure graphene, we demonstrate a gap formation in the density of states and the corresponding optical conductivity. We highlight the distinction between such a gap formation and the so-called Pauli blocking effect. Next, we apply this idea to graphene with adatoms by introducing magnetic interactions between the carrier spins and the spins of the adatoms. Exploring various possible ground-state spin configurations of the adatoms, we find that the antiferromagnetic configuration yields the lowest total electronic energy and is the only configuration that forms a gap. Furthermore, we analyze four different circumstances leading to similar gaplike structures and propose a means to interpret the magneticity and the possible orderings of the adatoms on graphene solely from the optical conductivity data. We apply this analysis to the recently reported experimental data of oxygenated graphene.

  5. Group Work and the Learning of Critical Thinking in the Hong Kong Secondary Liberal Studies Curriculum

    ERIC Educational Resources Information Center

    Fung, Dennis; Howe, Christine

    2014-01-01

    This article reports the findings of a one-year longitudinal study that investigated the impact of group work on the development of students' critical thinking in Hong Kong secondary schools. It explores whether the participation of teachers in a group-based teaching intervention adapted from an earlier study conducted in the United Kingdom (UK)…

  6. What Do Children Know? Comparative Education Review. International Studies on Educational Achievement. Vol. 18, No. 2.

    ERIC Educational Resources Information Center

    Postlethwaite, T. Neville, Ed.

    1974-01-01

    This issue of the Comparative Education Review focuses on analysis of data gathered by 19 countries participating in a six-subject survey conducted by the International Association for the Evaluation of Educational Achievement (IEA). The purpose of this and earlier IEA research (a pilot study and a mathematics study undertaken on the basis of the…

  7. Sonography-guided recording for superficial peroneal sensory nerve conduction study.

    PubMed

    Kim, Ki Hoon; Park, Byung Kyu; Kim, Dong Hwee; Kim, Yuntae

    2018-04-01

    We sought to establish the optimal recording position for antidromic conduction of the superficial peroneal nerve (SPN) by using ultrasonography (USG). The sensory nerve action potentials (SNAPs) of the intermediate dorsal cutaneous nerve (IDCN) and medial dorsal cutaneous nerve (MDCN) in 64 limbs of 32 healthy participants were recorded (nerve conduction study [NCS]-1). Both nerves were identified by using USG, and the SNAPs were obtained from the USG-guided repositioned electrodes (NCS-2). The IDCN and MDCN were located at 29.3% ± 5.1% and 43.9% ± 4.9% of the intermalleolar distance from the lateral malleolus, respectively. Significantly greater amplitude was shown for SNAPs of both nerves in NCS-2 versus NCS-1. The optimal recording position is likely to be lateral, one-third from the lateral malleolus for the IDCN, and just lateral to the midpoint of the intermalleolar line for the MDCN. When the SPN response is unexpectedly attenuated, USG-guided repositioning of the electrodes should be considered. Muscle Nerve 57: 628-633, 2018. © 2017 Wiley Periodicals, Inc.

  8. Materials characterization study of conductive flexible second surface mirrors

    NASA Technical Reports Server (NTRS)

    Levadou, F.; Bosma, S. J.; Paillous, A.

    1981-01-01

    The status of prequalification and qualification work on conductive flexible second surface mirrors is described. The basic material is FEP Teflon witn either aluminium or silver vacuum deposited reflectors. The top layer has been made conductive by deposition of layer of a indium oxide. The results of a prequalification program comprised of decontamination, humidity, thermal cycling, thermal shock and vibration tests are presented. Thermo-optical and electrical properties. The results of a prequalification program comprised of decontamination, humidity, thermal cycling, thermal shock and vibration tests are presented. Thermo-optical and electrical properties, the electrostatic behavior of the materials under simulated substorm environment and electrical conductivity at low temperatures are characterized. The effects of simulated ultra violet and particles irradiation on electrical and thermo-optical properties of the materials are also presented.

  9. Population dynamics of Meloidogyne arenaria and Pasteuria penetrans in a long-term crop rotation study.

    USDA-ARS?s Scientific Manuscript database

    The endospore-forming bacterium Pasteuria penetrans is an obligate parasite of root-knot nematodes (Meloidogyne spp.). This study was a continuation of earlier research to determine the effect of crop sequence on abundance of the bacterium, and was conducted from 2000 to 2008 at a field site natura...

  10. Thermal conductivity improvement in carbon nanoparticle doped PAO oil: An experimental study

    NASA Astrophysics Data System (ADS)

    Shaikh, S.; Lafdi, K.; Ponnappan, R.

    2007-03-01

    The present work involves a study on the thermal conductivity of nanoparticle-oil suspensions for three types of nanoparticles, namely, carbon nanotubes (CNTs), exfoliated graphite (EXG), and heat treated nanofibers (HTT) with PAO oil as the base fluid. To accomplish the above task, an experimental analysis is performed using a modern light flash technique (LFA 447) for measuring the thermal conductivity of the three types of nanofluids, for different loading of nanoparticles. The experimental results show a similar trend as observed in literature for nanofluids with a maximum enhancement of approximately 161% obtained for the CNT-PAO oil suspension. The overall percent enhancements for different volume fractions of the nanoparticles are highest for the CNT-based nanofluid, followed by the EXG and the HTT. The findings from this study for the three different types of carbon nanoparticles can have great potential in the field of thermal management.

  11. Thermal conduction study of warm dense aluminum by proton differential heating

    NASA Astrophysics Data System (ADS)

    Ping, Y.; Kemp, G.; McKelvey, A.; Fernandez-Panella, A.; Shepherd, R.; Collins, G.; Sio, H.; King, J.; Freeman, R.; Hua, R.; McGuffey, C.; Kim, J.; Beg, F.

    2016-10-01

    A differential heating platform has been developed for thermal conduction study (Ping et al. PoP 2015), where a temperature gradient is induced and subsequent heat flow is probed by time-resolved diagnostics. An experiment using proton differential heating has been carried out at Titan laser for Au/Al targets. Two single-shot time-resolved diagnostics are employed, SOP (streaked optical pyrometry) for surface temperature and FDI (Fourier Domain Interferometry) for surface expansion. Hydrodynamic simulations show that after 15ps, absorption in underdense plasma needs to be taken into account to correctly interpret SOP data. Comparison between simulations with different thermal conductivity models and a set of data with varying target thickness will be presented. This work was performed under DOE contract DE-AC52-07NA27344 with support from OFES Early Career program and LLNL LDRD program.

  12. Homophobia and the Transition to Adulthood: A Three Year Panel Study among Belgian Late Adolescents and Young Adults, 2008-2011

    ERIC Educational Resources Information Center

    Hooghe, Marc; Meeusen, Cecil

    2012-01-01

    Studies on homophobia among adolescents routinely depart from the assumption that this attitude will be continued into adulthood. However, little research has been conducted on how the transition toward adulthood actually affects homophobia. While earlier studies relied on cross-sectional observations, the present analysis makes use of the Belgian…

  13. Juvenile delinquency and psychopathic traits: an empirical study with Portuguese adolescents.

    PubMed

    Pechorro, Pedro; Gonçalves, Rui Abrunhosa; Maroco, João; Gama, Ana Paula; Neves, Saul; Nunes, Cristina

    2014-02-01

    The objective of the present study was to analyze the role of psychopathic traits in juvenile delinquency. Using a sample of 543 young males from the Juvenile Detention Centers of the Portuguese Ministry of Justice and from schools in the Lisbon region, a group of high psychopathic traits (n = 281) and a group of low psychopathic traits (n = 262) were formed based on the Portuguese version of Antisocial Process Screening Device (APSD). Results showed that youths with high psychopathic traits start engaging in criminal activities earlier in life, come into contact with the justice system earlier in life, and have higher levels of conduct disorder, behavior problems, and delinquent behaviors as well as lower levels of self-esteem.

  14. Modelling the Effect of Fruit Growth on Surface Conductance to Water Vapour Diffusion

    PubMed Central

    GIBERT, CAROLINE; LESCOURRET, FRANÇOISE; GÉNARD, MICHEL; VERCAMBRE, GILLES; PÉREZ PASTOR, ALEJANDRO

    2005-01-01

    • Background and Aims A model of fruit surface conductance to water vapour diffusion driven by fruit growth is proposed. It computes the total fruit conductance by integrating each of its components: stomata, cuticle and cracks. • Methods The stomatal conductance is computed from the stomatal density per fruit and the specific stomatal conductance. The cuticular component is equal to the proportion of cuticle per fruit multiplied by its specific conductance. Cracks are assumed to be generated when pulp expansion rate exceeds cuticle expansion rate. A constant percentage of cracks is assumed to heal each day. The proportion of cracks to total fruit surface area multiplied by the specific crack conductance accounts for the crack component. The model was applied to peach fruit (Prunus persica) and its parameters were estimated from field experiments with various crop load and irrigation regimes. • Key Results The predictions were in good agreement with the experimental measurements and for the different conditions (irrigation and crop load). Total fruit surface conductance decreased during early growth as stomatal density, and hence the contribution of the stomatal conductance, decreased from 80 to 20 % with fruit expansion. Cracks were generated for fruits exhibiting high growth rates during late growth and the crack component could account for up to 60 % of the total conductance during the rapid fruit growth. The cuticular contribution was slightly variable (around 20 %). Sensitivity analysis revealed that simulated conductance was highly affected by stomatal parameters during the early period of growth and by both crack and stomatal parameters during the late period. Large fruit growth rate leads to earlier and greater increase of conductance due to higher crack occurrence. Conversely, low fruit growth rate accounts for a delayed and lower increase of conductance. • Conclusions By predicting crack occurrence during fruit growth, this model could be helpful

  15. Synthesis, characterization and AC conductivity studies of silver doped conducting polyaniline/graphene/SrTiO3 composites

    NASA Astrophysics Data System (ADS)

    Vinay, K.; Shivakumar, K.; Ravikiran, Y. T.; Revanasiddappa, M.

    2018-05-01

    The present work is an investigation of ac conduction behaviour and dielectric response of Polyaniline/Ag/Graphene/SrTiO3 (PAGS) composite prepared by in-situ chemical oxidative interfacial polymerization using (NH4)2S2O8 as an oxidising agent at 0-5°C. The structural characterization of the samples was examined using FT-IR and XRD techniques. The ac conductivity and dielectric response of synthesized polymer composites were investigated at room temperature in the frequency range varying from 5 × 101 - 5 × 106 Hz using HIOKI make 3532-50 LCR Hi-tester. The ac conductivity increases with increase in frequency and follows the regular trend, the real dielectric constant (ɛ') and imaginary dielectric constant (ɛ'') decreases with increase in frequency and exhibits almost zero dielectric loss at higher frequencies, which suggests that the composite is a lossless material at frequencies beyond 3Hz.

  16. Numerical Study of Mixing Thermal Conductivity Models for Nanofluid Heat Transfer Enhancement

    NASA Astrophysics Data System (ADS)

    Pramuanjaroenkij, A.; Tongkratoke, A.; Kakaç, S.

    2018-01-01

    Researchers have paid attention to nanofluid applications, since nanofluids have revealed their potentials as working fluids in many thermal systems. Numerical studies of convective heat transfer in nanofluids can be based on considering them as single- and two-phase fluids. This work is focused on improving the single-phase nanofluid model performance, since the employment of this model requires less calculation time and it is less complicated due to utilizing the mixing thermal conductivity model, which combines static and dynamic parts used in the simulation domain alternately. The in-house numerical program has been developed to analyze the effects of the grid nodes, effective viscosity model, boundary-layer thickness, and of the mixing thermal conductivity model on the nanofluid heat transfer enhancement. CuO-water, Al2O3-water, and Cu-water nanofluids are chosen, and their laminar fully developed flows through a rectangular channel are considered. The influence of the effective viscosity model on the nanofluid heat transfer enhancement is estimated through the average differences between the numerical and experimental results for the nanofluids mentioned. The nanofluid heat transfer enhancement results show that the mixing thermal conductivity model consisting of the Maxwell model as the static part and the Yu and Choi model as the dynamic part, being applied to all three nanofluids, brings the numerical results closer to the experimental ones. The average differences between those results for CuO-water, Al2O3-water, and CuO-water nanofluid flows are 3.25, 2.74, and 3.02%, respectively. The mixing thermal conductivity model has been proved to increase the accuracy of the single-phase nanofluid simulation and to reveal its potentials in the single-phase nanofluid numerical studies.

  17. Comprehensive Study of Educational Technology Programs Authorized from 1989-1992. Volume IV: California Technology Project.

    ERIC Educational Resources Information Center

    Far West Lab. for Educational Research and Development, San Francisco, CA.

    This report, the fourth in a series of six, describes the evaluative studies conducted during Phase II of the California Educational Technology Assessment Program, the California Technology Project (CTP), and the CTP Regional Consortia. The report begins with background information on the CTP, starting with the earlier statewide network of…

  18. Oral Exposure to Paraquat Triggers Earlier Expression of Phosphorylated α-Synuclein in the Enteric Nervous System of A53T Mutant Human α-Synuclein Transgenic Mice

    PubMed Central

    Naudet, Nicolas; Antier, Emilie; Gaillard, Damien; Morignat, Eric; Lakhdar, Latifa; Baron, Thierry; Bencsik, Anna

    2017-01-01

    Abstract The misfolded α-synuclein protein, phosphorylated at serine 129 (pSer129 α-syn), is the hallmark of Parkinson disease (PD). Detected also in the enteric nervous system (ENS), it supports the recent theory that PD could start in the gut, rather than the brain. In a previous study, using a transgenic mouse model of human synucleinopathies expressing the A53T mutant α-synuclein (TgM83), in which a neurodegenerative process associated with α-synuclein occurs spontaneously in the brain, we have shown earlier onset of pSer129 α-syn in the ENS. Here, we used this model to study the impact of paraquat (PQ) a neurotoxic herbicide incriminated in PD in agricultural workers) on the enteric pSer129 α-syn expression in young mice. Orally delivered in the drinking water at 10 mg/kg/day for 6–8 weeks, the impact of PQ was measured in a time-dependent manner on weight, locomotor abilities, pSer129 α-syn, and glial fibrillary acidic protein (GFAP) expression levels in the ENS. Remarkably, pSer129 α-syn was detected in ENS earlier under PQ oral exposure and enteric GFAP expression was also increased. These findings bring additional support to the theory that neurotoxic agents such as PQ initiate idiopathic PD after oral delivery. PMID:29040593

  19. Oral Exposure to Paraquat Triggers Earlier Expression of Phosphorylated α-Synuclein in the Enteric Nervous System of A53T Mutant Human α-Synuclein Transgenic Mice.

    PubMed

    Naudet, Nicolas; Antier, Emilie; Gaillard, Damien; Morignat, Eric; Lakhdar, Latifa; Baron, Thierry; Bencsik, Anna

    2017-12-01

    The misfolded α-synuclein protein, phosphorylated at serine 129 (pSer129 α-syn), is the hallmark of Parkinson disease (PD). Detected also in the enteric nervous system (ENS), it supports the recent theory that PD could start in the gut, rather than the brain. In a previous study, using a transgenic mouse model of human synucleinopathies expressing the A53T mutant α-synuclein (TgM83), in which a neurodegenerative process associated with α-synuclein occurs spontaneously in the brain, we have shown earlier onset of pSer129 α-syn in the ENS. Here, we used this model to study the impact of paraquat (PQ) a neurotoxic herbicide incriminated in PD in agricultural workers) on the enteric pSer129 α-syn expression in young mice. Orally delivered in the drinking water at 10 mg/kg/day for 6-8 weeks, the impact of PQ was measured in a time-dependent manner on weight, locomotor abilities, pSer129 α-syn, and glial fibrillary acidic protein (GFAP) expression levels in the ENS. Remarkably, pSer129 α-syn was detected in ENS earlier under PQ oral exposure and enteric GFAP expression was also increased. These findings bring additional support to the theory that neurotoxic agents such as PQ initiate idiopathic PD after oral delivery. © 2017 American Association of Neuropathologists, Inc.

  20. Techniques for Conducting Effective Concept Design and Design-to-Cost Trade Studies

    NASA Technical Reports Server (NTRS)

    Di Pietro, David A.

    2015-01-01

    Concept design plays a central role in project success as its product effectively locks the majority of system life cycle cost. Such extraordinary leverage presents a business case for conducting concept design in a credible fashion, particularly for first-of-a-kind systems that advance the state of the art and that have high design uncertainty. A key challenge, however, is to know when credible design convergence has been achieved in such systems. Using a space system example, this paper characterizes the level of convergence needed for concept design in the context of technical and programmatic resource margins available in preliminary design and highlights the importance of design and cost evaluation learning curves in determining credible convergence. It also provides techniques for selecting trade study cases that promote objective concept evaluation, help reveal unknowns, and expedite convergence within the trade space and conveys general practices for conducting effective concept design-to-cost studies.

  1. How to Develop Critical Thinking Skills Within the Armys Officer Education System (OES) Earlier in an Officer’s Career

    DTIC Science & Technology

    2016-02-13

    thinking emerges.”31 Military leaders should minimize bureaucracy when possible in an attempt to facilitate creative thinking . Consequently, a...AIR WAR COLLEGE AIR UNIVERSITY HOW TO DEVELOP CRITICAL THINKING SKILLS WITHIN THE ARMY’S OFFICER EDUCTION SYSTEM (OES) EARLIER IN AN...Force Dragon’s Heart.” iv Abstract Critical thinking skills are required by strategic leaders to solve complex problems in an environment

  2. Single-molecule conductance studies of photo-active and photochromic molecules

    NASA Astrophysics Data System (ADS)

    Tam, E. S.; Parks, J. J.; Santiago-Berrios, M. B.; Zhong, Y.-W.; Abruna, H. D.; Ralph, D. C.

    2010-03-01

    We perform statistical measurements of single molecule conductance in repeatedly-formed metal-molecule-metal junctions at room temperature. Our results on diaminoalkanes are consistent with those reported by the Venkataraman group. We focus on photo-active and photochromic molecules, including a series of transition-metal complexes with different metal centers and endgroups. We compare the trend in conductance across the family of complexes with that expected from electrochemical measurements. We will also report initial results on the voltage dependence of single-molecule conductances and the effects of optical excitations.

  3. Conductivity study and fourier transform infrared (FTIR) characterization of methyl cellulose solid polymer electrolyte with sodium iodide conducting ion

    NASA Astrophysics Data System (ADS)

    Abiddin, Jamal Farghali Bin Zainal; Ahmad, Azizah Hanom

    2015-08-01

    Sodium ion (Na+) based solid polymer electrolyte (SPE) has been prepared using solution cast technique with distilled water as solvent and Methylcellulose (MC) as a polymer host. Methylcellulose polymer was chosen as the polymer host due to the abundance of lone pair electrons in the carbonyl and C-O-C constituents, which in turn provide multiple hopping sites for the Na+ conducting ions. Variable compositions of sodium iodide (NaI) salt were prepared to investigate the optimum MC-NaI weight ratio. Results from Electrical Impedance Spectroscopy (EIS) technique show that pure methylcellulose has a low conductivity of 3.61 × 10-11 S/cm.The conductivity increases as NaI content increases up to optimum NaIcomposition of 40 wt%, which yields an average conductivity of 2.70 × 10-5 S/cm.

  4. Composition and conductance distributions of single GeSi quantum rings studied by conductive atomic force microscopy combined with selective chemical etching.

    PubMed

    Lv, Y; Cui, J; Jiang, Z M; Yang, X J

    2013-02-15

    Atomic force microscopy imaging combined with selective chemical etching is employed to quantitatively investigate three-dimensional (3D) composition distributions of single GeSi quantum rings (QRs). In addition, the 3D quantitative composition distributions and the corresponding conductance distributions are simultaneously obtained on the same single GeSi QRs by conductive atomic force microscopy combined with selective chemical etching, allowing us to investigate the correlations between the conductance and composition distributions of single QRs. The results show that the QRs' central holes have higher Ge content, but exhibit lower conductance, indicating that the QRs' conductance distribution is not consistent with their composition distribution. By comparing the topography, composition and conductance profiles of the same single QRs before and after different etching processes, it is found that the conductance distributions of GeSi QRs do not vary with the change of composition distribution. Instead, the QRs' conductance distributions are found to be consistent with their topographic shapes, which can be supposed to be due to the shape determined electronic structures.

  5. Unusually conductive carbon-inherently conducting polymer (ICP) composites: Synthesis and characterization

    NASA Astrophysics Data System (ADS)

    Bourdo, Shawn Edward

    Raman spectroscopy, X-ray diffraction, and thermal analysis suggesting a more crystalline graphite matrix due to intimate interactions with PANI that resulted in a charge transfer. Confirmation of charge transfer was observed through magnetic susceptibility, electron paramagnetic resonance, and temperature dependent electrical conductivity studies.

  6. The Stability of Genetic Determination from Age 2 to Age 9: A Longitudinal Twin Study.

    ERIC Educational Resources Information Center

    Lytton, Hugh; And Others

    A longitudinal investigation of the social and cognitive development of male twins was conducted when twins were 2.5 years of age, and again when they were 8- to 10-years-old. This study was designed to re-examine the heritability of the traits studied at the earlier age and, thus, to address the question of the stability of genetic determination.…

  7. Experimental study of thermal conductivity of pyrolysised materials by means of a flat layer

    NASA Astrophysics Data System (ADS)

    Vaniushkin, V. D.; Popov, S. K.; Sidenkov, D. V.

    2017-11-01

    Recycling of tires is currently a very important task. One of the areas of recycling tires is their low-temperature pyrolysis to produce marketable products - liquid fraction and a solid coke residue. For the development of the pyrolysis installation it is important to know the thermal conductivity of the coke residue at different temperatures of pyrolysis of initial material. As a property of matter, thermal conductivity depends in general on temperature and pressure. For materials with some structure, such as porous materials, the thermal conductivity depends on the characteristics of the structure. The thermal conductivity of the porous coke residue at pyrolysis temperatures of 300 0C, 400 0C, 500 0C and atmospheric pressure was studied experimentally at the laboratory unit of the department of “Theoretical basis of heat engineering” using the method of the flat layer in the temperature range 5…100 0C. Experimentally proved temperature dependencies of the coefficient of thermal conductivity of the coke residue are built to improve the accuracy of calculations of constructive and regime parameters of the pyrolysis installation.

  8. Earlier flowering did not alter pollen limitation in an early flowering shrub under short-term experimental warming.

    PubMed

    Pan, Cheng-Chen; Feng, Qi; Zhao, Ha-Lin; Liu, Lin-De; Li, Yu-Lin; Li, Yu-Qiang; Zhang, Tong-Hui; Yu, Xiao-Ya

    2017-06-05

    In animal pollinated plants, phenological shifts caused by climate change may have important ecological consequences. However, no empirical evidence exists at present on the consequences that flowering phenology shifts have on the strength of pollen limitation under experimental warming. Here, we investigated the effects of experimental warming on flowering phenology, flower density, reproductive success, and pollen limitation intensity in Caragana microphylla and evaluated whether earlier flowering phenology affected plant reproduction and the level of pollen limitation using warmed and unwarmed open top chambers in the Horqin Sandy Land of Inner Mongolia, northern China. The results of this study indicated that artificial warming markedly advanced flower phenology rather than extending the duration of the flowering. Additionally, warming was found to significantly reduce flower density which led to seed production reduction, since there were insignificant effects observed on fruit set and seed number per fruit. Experimental floral manipulations showed that warming did not affect pollen limitation. These results revealed the negative effects of advanced phenology induced by warming on flower density and reproductive output, as well as the neutral effects on reproductive success and pollen limitation intensity of long surviving plants.

  9. Verbal abuse, like physical and sexual abuse, in childhood is associated with an earlier onset and more difficult course of bipolar disorder.

    PubMed

    Post, Robert M; Altshuler, Lori L; Kupka, Ralph; McElroy, Susan L; Frye, Mark A; Rowe, Michael; Leverich, Gabriele S; Grunze, Heinz; Suppes, Trisha; Keck, Paul E; Nolen, Willem A

    2015-05-01

    Physical or sexual abuse in childhood is known to have an adverse effect on the course of bipolar disorder, but the impact of verbal abuse has not been well elucidated. We examined the occurrence and frequency (never to frequently) of each type of abuse in childhood in 634 US adult outpatients (average age 40 years). Patients gave informed consent and provided information about their age of onset and course of illness prior to study entry. Verbal abuse alone occurred in 24% of the patients. Similar to a history of physical or sexual abuse, a history of verbal abuse was related to an earlier age of onset of bipolar disorder and other poor prognosis characteristics, including anxiety and substance abuse comorbidity, rapid cycling, and a deteriorating illness course as reflected in ratings of increasing frequency or severity of mania and depression. A lasting adverse impact of the experience of verbal abuse in childhood is suggested by its relationship to an earlier age of onset of bipolar disorder, other poor prognosis factors, and a deteriorating course of illness. Verbal abuse is a common confound in comparison groups defined by a lack of physical or sexual abuse. Ameliorating the impact of verbal abuse on the unfolding course of bipolar disorder appears to be an important target of therapeutics and worthy of attempts at primary and secondary prophylaxis. Family-based treatments that focus on psychoeducation, enhancing intra-family communication, and coping skills may be particularly helpful. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Antimicrobial susceptibility of pathogens isolated from surgical site infections in Japan: Comparison of data from nationwide surveillance studies conducted in 2010 and 2014-2015.

    PubMed

    Takesue, Yoshio; Kusachi, Shinya; Mikamo, Hiroshige; Sato, Junko; Watanabe, Akira; Kiyota, Hiroshi; Iwata, Satoshi; Kaku, Mitsuo; Hanaki, Hideaki; Sumiyama, Yoshinobu; Kitagawa, Yuko; Mizuguchi, Toru; Ambo, Yoshiyasu; Konosu, Masafumi; Ishibashi, Keiichiro; Matsuda, Akihisa; Hase, Kazuo; Harihara, Yasushi; Okabayashi, Koji; Seki, Shiko; Hara, Takuo; Matsui, Koshi; Matsuo, Yoichi; Kobayashi, Minako; Kubo, Shoji; Uchiyama, Kazuhisa; Shimizu, Junzo; Kawabata, Ryohei; Ohge, Hiroki; Akagi, Shinji; Oka, Masaaki; Wakatsuki, Toshiro; Suzuki, Katsunori; Okamoto, Kohji; Yanagihara, Katsunori

    2017-06-01

    A nationwide survey was conducted in Japan from 2014 to 2015 to investigate the antimicrobial susceptibility of pathogens isolated from surgical site infections (SSI). The resulting data were compared with that obtained in an earlier survey, conducted in 2010. Seven main organisms were collected, and 883 isolates were studied. A significant reduction in methicillin resistance was observed among Staphylococcus aureus isolates, dropping from 72.5% in 2010 to 53.8% in 2014-2015 (p < 0.001). MRSA isolates with a vancomycin minimum inhibitory concentration (MIC) of 2 μg/mL accounted for 1.2% of all MRSA isolates, which was significantly lower than in 2010 (9.7%, p = 0.029). Of the Escherichia coli isolates, 23.0% produced an extended spectrum β-lactamase (ESBL) in the 2014-2015 survey, which was a significant increase from 9.5% in 2010 (p = 0.011). The geometric mean MICs for ESBL-producing isolates were 0.07 μg/mL for meropenem, 9.51 μg/mL for tazobactam/piperacillin, 0.15 μg/mL for flomoxef, and 1.56 μg/mL for gentamycin. There was a significant increase in the isolation rate of non-fragilis Bacteroides among Bacteroides fragilis group species between the two study periods (35.2% vs. 53.1%, p = 0.007). More than 90% of isolates belonging to the B. fragilis group remained susceptible to tazobactam/piperacillin, meropenem, and metronidazole. In contrast, lower levels of susceptibility were observed for cefmetazole (49.6%), moxifloxacin (61.9%), and clindamycin (46.9%). Non-fragilis Bacteroides isolates had lower rates of antibiotic susceptibility compared with B. fragilis. Overall, the surveillance data clarified trends in antimicrobial susceptibility for organisms commonly associated with SSI. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  11. Pericardial Fat is Associated With Atrial Conduction: The Framingham Heart Study

    PubMed Central

    Friedman, Daniel J.; Wang, Na; Meigs, James B.; Hoffmann, Udo; Massaro, Joseph M.; Fox, Caroline S.; Magnani, Jared W.

    2014-01-01

    Background Obesity is associated with altered atrial electrophysiology and a prominent risk factor for atrial fibrillation. Body mass index, the most widely used adiposity measure, has been related to atrial electrical remodeling. We tested the hypothesis that pericardial fat is independently associated with electrocardiographic measures of atrial conduction. Methods and Results We performed a cross‐sectional analysis of 1946 Framingham Heart Study participants (45% women) to determine the relation between pericardial fat and atrial conduction as measured by P wave indices (PWI): PR interval, P wave duration (P‐duration), P wave amplitude (P‐amplitude), P wave area (P‐area), and P wave terminal force (P‐terminal). We performed sex‐stratified linear regression analyses adjusted for relevant clinical variables and ectopic fat depots. Each 1‐SD increase in pericardial fat was significantly associated with PR interval (β=1.7 ms, P=0.049), P‐duration (β=2.3 ms, P<0.001), and P‐terminal (β=297 μV·ms, P<0.001) among women; and P‐duration (β=1.2 ms, P=0.002), P‐amplitude (β=−2.5 μV, P<0. 001), and P‐terminal (β=160 μV·ms, P=0.002) among men. Among both sexes, pericardial fat was significantly associated with P‐duration in analyses additionally adjusting for visceral fat or intrathoracic fat; a similar but non‐significant trend existed with P‐terminal. Among women, pericardial fat was significantly associated with P wave area after adjustment for visceral and intrathoracic fat. Conclusions Pericardial fat is associated with atrial conduction as quantified by PWI, even with adjustment for extracardiac fat depots. Further studies are warranted to identify the mechanisms through which pericardial fat may modify atrial electrophysiology and promote subsequent risk for arrhythmogenesis. PMID:24595189

  12. Conducting Real-Time Videofluoroscopic Swallow Study via Telepractice: A Preliminary Feasibility and Reliability Study.

    PubMed

    Burns, Clare L; Ward, Elizabeth C; Hill, Anne J; Phillips, Nick; Porter, Linda

    2016-06-01

    A small number of studies have examined the feasibility of conducting videofluoroscopic swallow studies (VFSS) via telepractice. While the results have confirmed this potential, the systems tested to date have either reported issues that impacted the ability to analyze/interpret the VFSS recordings in real time, or they were not designed to enable real-time interpretation. Further system design is needed to establish a telepractice model that enables the VFSS assessment to be both guided and interpreted live in real time. The aim of this study was to test the feasibility and reliability of using a telepractice system to enable live VFSS assessment. Twenty adult patients underwent a VFSS assessment directed by a telepractice SLP with competency in VFSS located in another room of the hospital. The telepractice clinician led the sessions using a C20 Cisco TelePresence System. This was linked in real time via a secure telehealth network (at 4 megabits per second (Mbit/s)) to a C60 Cisco TelePresence System located in a fluoroscopy suite, connected to the digital fluoroscopy system. Levels of agreement were calculated between the telepractice clinician and a face-to-face clinician who simultaneously rated the VFSS in real time. High levels of agreement for swallowing parameters (range = 75-100 %; k = -0.34 to 1.0) and management decisions (range = 70-100 %, k = 0.64-1.0) were found. A post-session questionnaire revealed clinicians agreed that the telepractice system enabled successful remote assessment of VFSS. The findings support the potential to conduct live VFSS assessment via a telepractice model.

  13. Single‐Molecule Conductance Studies of Organometallic Complexes Bearing 3‐Thienyl Contacting Groups

    PubMed Central

    Bock, Sören; Al‐Owaedi, Oday A.; Eaves, Samantha G.; Milan, David C.; Lemmer, Mario; Skelton, Brian W.; Osorio, Henrry M.; Nichols, Richard J.; Higgins, Simon J.; Cea, Pilar; Long, Nicholas J.; Albrecht, Tim

    2017-01-01

    Abstract The compounds and complexes 1,4‐C6H4(C≡C‐cyclo‐3‐C4H3S)2 (2), trans‐[Pt(C≡C‐cyclo‐3‐C4H3S)2(PEt3)2] (3), trans‐[Ru(C≡C‐cyclo‐3‐C4H3S)2(dppe)2] (4; dppe=1,2‐bis(diphenylphosphino)ethane) and trans‐[Ru(C≡C‐cyclo‐3‐C4H3S)2{P(OEt)3}4] (5) featuring the 3‐thienyl moiety as a surface contacting group for gold electrodes have been prepared, crystallographically characterised in the case of 3–5 and studied in metal|molecule|metal junctions by using both scanning tunnelling microscope break‐junction (STM‐BJ) and STM‐I(s) methods (measuring the tunnelling current (I) as a function of distance (s)). The compounds exhibit similar conductance profiles, with a low conductance feature being more readily identified by STM‐I(s) methods, and a higher feature by the STM‐BJ method. The lower conductance feature was further characterised by analysis using an unsupervised, automated multi‐parameter vector classification (MPVC) of the conductance traces. The combination of similarly structured HOMOs and non‐resonant tunnelling mechanism accounts for the remarkably similar conductance values across the chemically distinct members of the family 2–5. PMID:27897344

  14. Recommendations for designing and conducting veterinary clinical pathology biologic variation studies.

    PubMed

    Freeman, Kathleen P; Baral, Randolph M; Dhand, Navneet K; Nielsen, Søren Saxmose; Jensen, Asger L

    2017-06-01

    The recent creation of a veterinary clinical pathology biologic variation website has highlighted the need to provide recommendations for future studies of biologic variation in animals in order to help standardize and improve the quality of published information and to facilitate review and selection of publications as standard references. The following recommendations are provided in the format and order commonly found in veterinary publications. A checklist is provided to aid in planning, implementing, and evaluating veterinary studies on biologic variation (Appendix S1). These recommendations provide a valuable resource for clinicians, laboratorians, and researchers interested in conducting studies of biologic variation and in determining the quality of studies of biologic variation in veterinary laboratory testing. © 2017 American Society for Veterinary Clinical Pathology.

  15. [Relationships between well-being and social support: a meta analysis of studies conducted in Turkey].

    PubMed

    Yalçın, İlhan

    2015-01-01

    The purpose of this study was to investigate overall relationships between well-being and social support through meta-analysis. Studies which investigated associations between social support and life satisfaction, subjective well-being, self-esteem, depression, loneliness were included in the meta-analysis. By doing literature review to assess studies for potential inclusion; studies were included which met the inclusion criteria. Inclusion criteria were that studies must be conducted in Turkey and must report a correlation coefficient between study variables. Data were analyzed using a random effect model. It was found that there was a positive relationship between overall well-being and social support; level of social support was negatively correlated with depression and loneliness. For well-being variables, the mean effect size of perceived support from family and for depression/loneliness, the mean effect size of perceived support from friends were significantly stronger than other support sources. For both well-being variables and depression/loneliness variables, mean effect size of studies conducted with older people was significantly stronger than studies conducted with other age groups. Also, mean effect size of theses were significantly stronger than articles. The findings are expected to contribute to a better understanding of relationships between social support and well-being.

  16. Neurological Assessment and Nerve Conduction Study Findings in 22 Patients with Alkaptonuria from Jordan

    PubMed Central

    Alrawashdeh, Omar; Alsbou, Mohammad; Alzoubi, Hamed; Al-shagahin, Hani

    2017-01-01

    Alkaptonuria is a rare metabolic disease characterised by accumulative deposition of homogentisic acid in the connective tissue of the body. This results in early degeneration of tendons, cartilages, heart valves, and other tissues. The main objective of the study is to examine the possibility of the nervous system involvement in patients with alkaptonuria The sample consists of two groups; 22 patients with AKU and 20 controls. A neurological assessment has been carried out including detailed medical history, neurological examination, and a nerve conduction study of the nerves of the dominant hand. The prevalence of any abnormality was compared between the two groups using chi square test. The mean values of the nerve conduction study were compared between the two groups using student t-test. There was a higher prevalence of low back pain, hearing problems and tinnitus, numbness and neuropathic pain in alkaptonuria patients. There was no significant difference between the two groups in other conditions such as seizures, headache, and syncope. The values of the nerve conduction study did not show significant difference between the two groups. Neurologically related symptoms in alkaptonuria mostly represent complications of the connective tissue degeneration rather than direct involvement of the nervous system. This has been supported further by the normal findings of the neurophysiology study in patients with alkaptonuria. PMID:28217270

  17. Neurological Assessment and Nerve Conduction Study Findings in 22 Patients with Alkaptonuria from Jordan.

    PubMed

    Alrawashdeh, Omar; Alsbou, Mohammad; Alzoubi, Hamed; Al-Shagahin, Hani

    2016-11-02

    Alkaptonuria is a rare metabolic disease characterised by accumulative deposition of homogentisic acid in the connective tissue of the body. This results in early degeneration of tendons, cartilages, heart valves, and other tissues. The main objective of the study is to examine the possibility of the nervous system involvement in patients with alkaptonuria The sample consists of two groups; 22 patients with AKU and 20 controls. A neurological assessment has been carried out including detailed medical history, neurological examination, and a nerve conduction study of the nerves of the dominant hand. The prevalence of any abnormality was compared between the two groups using chi square test. The mean values of the nerve conduction study were compared between the two groups using student t-test. There was a higher prevalence of low back pain, hearing problems and tinnitus, numbness and neuropathic pain in alkaptonuria patients. There was no significant difference between the two groups in other conditions such as seizures, headache, and syncope. The values of the nerve conduction study did not show significant difference between the two groups. Neurologically related symptoms in alkaptonuria mostly represent complications of the connective tissue degeneration rather than direct involvement of the nervous system. This has been supported further by the normal findings of the neurophysiology study in patients with alkaptonuria.

  18. A Computational and Theoretical Study of Conductance in Hydrogen-bonded Molecular Junctions

    NASA Astrophysics Data System (ADS)

    Wimmer, Michael

    This thesis is devoted to the theoretical and computational study of electron transport in molecular junctions where one or more hydrogen bonds are involved in the process. While electron transport through covalent bonds has been extensively studied, in recent work the focus has been shifted towards hydrogen-bonded systems due to their ubiquitous presence in biological systems and their potential in forming nano-junctions between molecular electronic devices and biological systems. This analysis allows us to significantly expand our comprehension of the experimentally observed result that the inclusion of hydrogen bonding in a molecular junction significantly impacts its transport properties, a fact that has important implications for our understanding of transport through DNA, and nano-biological interfaces in general. In part of this work I have explored the implications of quasiresonant transport in short chains of weakly-bonded molecular junctions involving hydrogen bonds. I used theoretical and computational analysis to interpret recent experiments and explain the role of Fano resonances in the transmission properties of the junction. In a different direction, I have undertaken the study of the transversal conduction through nucleotide chains that involve a variable number of different hydrogen bonds, e.g. NH˙˙˙O, OH˙˙˙O, and NH˙˙˙N, which are the three most prevalent hydrogen bonds in biological systems and organic electronics. My effort here has focused on the analysis of electronic descriptors that allow a simplified conceptual and computational understanding of transport properties. Specifically, I have expanded our previous work where the molecular polarizability was used as a conductance descriptor to include the possibility of atomic and bond partitions of the molecular polarizability. This is important because it affords an alternative molecular description of conductance that is not based on the conventional view of molecular orbitals as

  19. Clinical report--guidelines for the ethical conduct of studies to evaluate drugs in pediatric populations.

    PubMed

    Shaddy, Robert E; Denne, Scott C

    2010-04-01

    The proper ethical conduct of studies to evaluate drugs in children is of paramount importance to all those involved in these types of studies. This report is an updated revision to the previously published guidelines from the American Academy of Pediatrics in 1995. Since the previous publication, there have been great strides made in the science and ethics of studying drugs in children. There have also been numerous legislative and regulatory advancements that have promoted the study of drugs in children while simultaneously allowing for the protection of this particularly vulnerable group. This report summarizes these changes and advances and provides a framework from which to guide and monitor the ethical conduct of studies to evaluate drugs in children.

  20. Bowel cancer screening is safe, detects earlier stage cancer and adenomas in 50% of cases: experience of the prevalent round of screening from two first wave centres in the North East of England.

    PubMed

    Rajasekhar, P T; Clifford, G M; Lee, T J W; Rutter, M D; Waddup, G; Ritchie, M; Nylander, D; Painter, J; Singh, J; Ward, I; Dempsey, N; Bowes, J; Handley, G; Henry, J; Rees, C J

    2012-01-01

    The NHS Bowel Cancer Screening Programme (BCSP) began roll-out in 2006 aiming to reduce cancer mortality through detection at an earlier stage. We report results from the prevalent round of screening at two first wave centres and compare with the UK pilot study. This is a service evaluation study. Data were collected prospectively for all individuals undergoing faecal occult blood testing (FOBt) and colonoscopy including: uptake and outcomes of FOBt, colonoscopic performance, findings, histological data and complications. Continuous data were compared using a two-tailed test of two proportions. The South of Tyne and Tees Bowel Cancer Screening centres. Participants of the BCSP. 1) Colonoscopy Quality Assurance and 2) Cancer stage shift. 195,772 individuals were invited to participate. Uptake was 54% and FOBt positivity 1.7%. 1524 underwent colonoscopy with caecal intubation in 1485 (97%). 180 (12%) cancers were detected. Dukes stages were: 76 (42%) A; 47 (26%) B; 47 (26%) C; 8 (4%) D and 2 (1%) unknown. This demonstrates a significantly earlier stage at diagnosis compared with data from 2867 non-screening detected cancers (p<0.001). Adenomas were detected in 758 (50%). One perforation occurred (0.07%) and two intermediate bleeds requiring transfusion only (0.12%). Both caecal intubation and adenoma detection were significantly higher than in the UK pilot study (p<0.001). The prevalent round of screening demonstrates a high adenoma and cancer detection rate and significantly earlier stage at diagnosis. Complications were few providing reassurance regarding safety. Efforts are required to improve uptake.

  1. Bowel cancer screening is safe, detects earlier stage cancer and adenomas in 50% of cases: experience of the prevalent round of screening from two first wave centres in the North East of England

    PubMed Central

    Rajasekhar, P T; Clifford, G M; Lee, T J W; Rutter, M D; Waddup, G; Ritchie, M; Nylander, D; Painter, J; Singh, J; Ward, I; Dempsey, N; Bowes, J; Handley, G; Henry, J; Rees, C J

    2012-01-01

    Objective The NHS Bowel Cancer Screening Programme (BCSP) began roll-out in 2006 aiming to reduce cancer mortality through detection at an earlier stage. We report results from the prevalent round of screening at two first wave centres and compare with the UK pilot study. Design This is a service evaluation study. Data were collected prospectively for all individuals undergoing faecal occult blood testing (FOBt) and colonoscopy including: uptake and outcomes of FOBt, colonoscopic performance, findings, histological data and complications. Continuous data were compared using a two-tailed test of two proportions. Setting The South of Tyne and Tees Bowel Cancer Screening centres. Patients Participants of the BCSP. Main Outcome Measures 1) Colonoscopy Quality Assurance and 2) Cancer stage shift. Results 195,772 individuals were invited to participate. Uptake was 54% and FOBt positivity 1.7%. 1524 underwent colonoscopy with caecal intubation in 1485 (97%). 180 (12%) cancers were detected. Dukes stages were: 76 (42%) A; 47 (26%) B; 47 (26%) C; 8 (4%) D and 2 (1%) unknown. This demonstrates a significantly earlier stage at diagnosis compared with data from 2867 non-screening detected cancers (p<0.001). Adenomas were detected in 758 (50%). One perforation occurred (0.07%) and two intermediate bleeds requiring transfusion only (0.12%). Both caecal intubation and adenoma detection were significantly higher than in the UK pilot study (p<0.001). Conclusions The prevalent round of screening demonstrates a high adenoma and cancer detection rate and significantly earlier stage at diagnosis. Complications were few providing reassurance regarding safety. Efforts are required to improve uptake. PMID:28839624

  2. Studies and projections of hydraulic conductivity of Devonian Plavinu and Daugava carbonate aquifers in Latvia

    NASA Astrophysics Data System (ADS)

    Perkone, E.; Delina, A.; Saks, T.; Raga, B.; Jātnieks, J.; Klints, I.; Popovs, K.; Babre, A.; Bikše, J.; Kalvāns, A.; Retike, I.; Ukass, J.

    2012-04-01

    Carbonate aquifers show a very wide range of hydrogeological characteristics. Carbonate rock hydrogeology display two extremes: on one hand hydrogeological properties of the carbonates are governed by the pathways of the preferential groundwater flow typical in karstic regions, on the other - some carbonate aquifers behave almost like a homogeneous, isotropic, porous medium. Most lie between these extremes, but these case variations complicates the study of carbonate aquifer properties. In this study the results of the hydraulic conductivity in carbonate aquifers measurements, hydraulic conductivity correlation between sediments lithology and the aquifer surface depth and fractures research is presented. Upper Devonian Frasnian stage Pļaviņu and Daugava carbonate aquifers in the Latvian part of the Baltic basin is considered. The aim of this research is to elaborate characteristic hydraulic conductivity values for each aquifer based on existing data of the pumping test results and other aquifer properties. Pļaviņu and Daugava carbonate aquifers mainly consist of jointed dolomite with intermediate layers of dolomitic marlstone, limestone, clays and gypsum. These aquifers are prevalent in most of the study area, except Northern and South - Eastern parts of the territory. In geological structure Daugava aquifer lies above Pļaviņu aquifer. Daugava aquifer depth changes from 10 - 20 and even less meters in Eastern part to 250 - 300 m in South - West part of study area, but thickness varies from few meters to 30 m. Pļaviņu aquifer surface depth varies from 20 - 30 m, but in uplands surface depth reaches more than 120 m, in Eastern part to more than 300 m in South - West part of study area. Aquifer average thickness varies from 20 - 40 m, but in areas with buried valleys thickness can be less than 10 meters. Outcrops of these sediments are occurring in banks of largest rivers and in some areas aquifers are karstified. In studies of the carbonate aquifers it is

  3. [Quality standards for epidemiologic cohort studies : An evaluated catalogue of requirements for the conduct and preparation of cohort studies].

    PubMed

    Schmidt, Carsten Oliver; Krabbe, Christine E M; Schössow, Janka; Berger, Klaus; Enzenbach, Cornelia; Kamtsiuris, Panagiotis; Schöne, Gina; Houben, Robin; Meisinger, Christa; Bamberg, Fabian; Hendel, Thomas; Selder, Sonja; Nonnemacher, Michael; Moebus, Susanne; Stausberg, Jürgen

    2018-01-01

    Cohort studies are a longitudinal observational study type. They are firmly established within epidemiology to assess the course of diseases and risk factors. Yet, standards to describe and evaluate quality characteristics of cohort studies need further development. Within the TMF ("Technologie- und Methodenplattform für die vernetzte medizinische Forschung e. V.") project "Quality management standards in cohort studies", a catalogue of requirements was compiled and evaluated, focusing on the preparation and conduct of epidemiologic cohort studies. The catalogue of requirements was established based on a consensus process between representatives of seven German epidemiologic cohort studies. For this purpose, a set of expert meetings (telephone, face-to-face, web-based) was conducted and the importance of each element of the catalogue was assessed as well as its implementation. A catalogue of requirements with 138 requirements was consented. It is structured into ten sections: 1. Study documentation; 2. Selection of instruments; 3. Study implementation, 4. Organizational structure; 5. Qualification and certification; 6. Participant recruitment; 7. Preparation, conduct and follow-up processing of examinations; 8. Study logistics and maintenance, 9. Data capture and data management; 10. Reporting and monitoring. In total, 41 elements were categorized as being essential, 91 as important, and 6 as less important. The catalogue of requirements provides a guideline to improve the preparation and operation of cohort studies. The evaluation of the importance and degree of implementation of requirements depended on the study design. With adaptations, the catalogue might be transferable to other study types.

  4. [Conduct disorders in seven-year-old children--results of ELSPAC study 1. Co-morbidity].

    PubMed

    Kukla, L; Hrubá, D; Tyrlík, M; Matejová, H

    2008-01-01

    The interest of experts in conduct disorders (CD) research is growing during the last two decades. The research areas include the diagnostics, ethiopathogenesis and treatment and also the comorbidity, especially with the hyperkinetic syndrome incidence (Attention Deficit Hyperactivity Disorder--ADHD). This paper intends to describe the conduct disorder occurrence and its other manifestations of divergence found during the investigation of children followed in the prospective longitudinal study ELSPAC in seven, respectively eight years of their age. Data of 6100 seven-year-old children characterizing their behaviour was collected from mothers and attending physicians. In the school year during which this investigation phase took place 2518 of the children reached eight years of age and their behaviour, temperament and school results were also evaluated by their teachers. The children were divided into three groups according to the presence or absence of the symptoms, which characterize conduct disorders (found by physicians): "stubborn negativistic behaviour", "inability to pay attention", "aggressiveness" and "inadequacy of reactions". The presence of two of these symptoms was found in 3%, presence of all four symptoms in additional 1.4% of children. Parents and teachers more often indicated various symptoms of hyperactivity in children with conduct disorders. In almost 5% of the ELSPAC cohort children in seven years of their age those symptoms were diagnosed, which match the Conduct Disorder criteria and Attention Deficit Hyperactivity Disorder (ADHD) criteria. In agreement with similar studies these frequent comorbidities were found: sleep disorders, psychomotor development disorders and laterality changes. The cognitive abilities evaluated by mothers and also teachers based on schoolwork results were more often worsened in children with conduct disorders. Various data indicating their worse social adaptability (which significantly disturbed the class) occurred

  5. Impaired small fiber conduction in patients with Fabry disease: a neurophysiological case–control study

    PubMed Central

    2013-01-01

    Background Fabry disease is an inborn lysosomal storage disorder which is associated with small fiber neuropathy. We set out to investigate small fiber conduction in Fabry patients using pain-related evoked potentials (PREP). Methods In this case–control study we prospectively studied 76 consecutive Fabry patients for electrical small fiber conduction in correlation with small fiber function and morphology. Data were compared with healthy controls using non-parametric statistical tests. All patients underwent neurological examination and were investigated with pain and depression questionnaires. Small fiber function (quantitative sensory testing, QST), morphology (skin punch biopsy), and electrical conduction (PREP) were assessed and correlated. Patients were stratified for gender and disease severity as reflected by renal function. Results All Fabry patients (31 men, 45 women) had small fiber neuropathy. Men with Fabry disease showed impaired cold (p < 0.01) and warm perception (p < 0.05), while women did not differ from controls. Intraepidermal nerve fiber density (IENFD) was reduced at the lower leg (p < 0.001) and the back (p < 0.05) mainly of men with impaired renal function. When investigating A-delta fiber conduction with PREP, men but not women with Fabry disease had lower amplitudes upon stimulation at face (p < 0.01), hands (p < 0.05), and feet (p < 0.01) compared to controls. PREP amplitudes further decreased with advance in disease severity. PREP amplitudes and warm (p < 0.05) and cold detection thresholds (p < 0.01) at the feet correlated positively in male patients. Conclusion Small fiber conduction is impaired in men with Fabry disease and worsens with advanced disease severity. PREP are well-suited to measure A-delta fiber conduction. PMID:23705943

  6. Kindergarten Teachers' Perspectives on Developmentally Appropriate Practices (DAP): A Study Conducted in Mumbai (India)

    ERIC Educational Resources Information Center

    Hegde, Archana V.; Cassidy, Deborah J.

    2009-01-01

    A qualitative study examining teachers' beliefs regarding developmentally appropriate practices was conducted in the city of Mumbai, India. Twelve kindergarten teacher's were interviewed for this study, and a constant comparative method was used to analyze the interviews. Six themes were identified within this study. The themes highlighted…

  7. Authoritarian parenting attitudes as a risk for conduct problems Results from a British national cohort study.

    PubMed

    Thompson, Anne; Hollis, Chris; Dagger, David Richards

    2003-04-01

    This study examines the associations, and possible causal relationship, between mothers' authoritarian attitudes to discipline and child behaviour using cross-sectional and prospective data from a large population sample surveyed in the 1970 British Cohort Study. Results show a clear linear relationship between the degree of maternal approval of authoritarian child-rearing attitudes and the rates of conduct problems at age 5 and age 10. This association is independent of the confounding effects of socio-economic status and maternal psychological distress. Maternal authoritarian attitudes independently predicted the development of conduct problems 5 years later at age 10. The results of this longitudinal study suggest that authoritarian parenting attitudes expressed by mothers may be of significance in the development of conduct problems.

  8. Conductivity study and fourier transform infrared (FTIR) characterization of methyl cellulose solid polymer electrolyte with sodium iodide conducting ion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abiddin, Jamal Farghali Bin Zainal; Ahmad, Azizah Hanom; Institute of Science, Universiti Teknologi MARA, 40450 Shah Alam, Selangor D.E.

    2015-08-28

    Sodium ion (Na{sup +}) based solid polymer electrolyte (SPE) has been prepared using solution cast technique with distilled water as solvent and Methylcellulose (MC) as a polymer host. Methylcellulose polymer was chosen as the polymer host due to the abundance of lone pair electrons in the carbonyl and C-O-C constituents, which in turn provide multiple hopping sites for the Na{sup +} conducting ions. Variable compositions of sodium iodide (NaI) salt were prepared to investigate the optimum MC-NaI weight ratio. Results from Electrical Impedance Spectroscopy (EIS) technique show that pure methylcellulose has a low conductivity of 3.61 × 10{sup −11} S/cm.Themore » conductivity increases as NaI content increases up to optimum NaIcomposition of 40 wt%, which yields an average conductivity of 2.70 × 10{sup −5} S/cm.« less

  9. The Connoisseurship of Conducting: A Qualitative Study of Exemplary Wind Band Conductors

    ERIC Educational Resources Information Center

    Barry, Nancy; Henry, Daniel

    2015-01-01

    This study aimed to gain an in-depth perspective through examining how the conducting pedagogy of three selected exemplary high school and college instrumental music conductors function within the context of an actual rehearsal. A typical rehearsal was video recorded, followed by a "think-aloud" session in which the conductor viewed the…

  10. Treatment of Comorbid Conduct Problems and Depression in Youth: A Pilot Study

    ERIC Educational Resources Information Center

    Wolff, Jennifer C.; Ollendick, Thomas H.

    2012-01-01

    The purpose of this study was to pilot a cognitive behavioral treatment protocol for adolescents with co-occurring conduct problems and depression. A non-concurrent multiple baseline design was used to assess the effectiveness of the intervention. A sample of five adolescents, aged 11 to 14 years, participated; all five families completed the…

  11. First-principles study of lattice thermal conductivity in ZrTe5 and HfTe5

    NASA Astrophysics Data System (ADS)

    Wang, Cong; Wang, Haifeng; Chen, Y. B.; Yao, Shu-Hua; Zhou, Jian

    2018-05-01

    Recently, the layered transition-metal pentatellurides ZrTe5 and HfTe5 have attracted increasing attention because of their interesting topological electronic properties. Nevertheless, some of their other good physical properties seem to be ignored now. Actually, both ZrTe5 and HfTe5 have high electric conductivities (>105 Ω-1 m-1) and Seebeck coefficients (> 100 μV/K) at room temperature, thus making them promising thermoelectric materials. However, the disadvantage is that the thermal conductivities of the two materials are relatively high according to the few available experiments; meanwhile, the detailed mechanism of the intrinsic thermal conductivity has not been studied yet. Based on the density functional theory and the Boltzmann transport theory, we present here the theoretical study of the intrinsic lattice thermal conductivities of ZrTe5 and HfTe5, which are found to be in the range of 5-8 W/mṡK at room temperature and well consistent with the experimental results. We also find that the thermal conductivities of the two materials are anisotropic, which are mainly caused by their anisotropic crystal structures. Based on the detailed analysis, we proposed that the thermal conductivities of the two materials could possibly be reduced by different kinds of structural engineering at the atomic and mesoscopic scales, such as alloying, doping, nano-structuring, and polycrystalline structuring, which could make ZrTe5 and HfTe5 good thermoelectric materials for room temperature thermoelectric applications.

  12. Electrically conductive ceramic powders

    NASA Astrophysics Data System (ADS)

    Lu, Yanxia

    1999-11-01

    Electrically conductive ceramic powders were investigated in this project. There are three ways to produce those materials. The first is doping alkali metal into the titanium dioxides in an inert or reducing atmosphere. The second is reducing un-doped titanium dioxide, forming a non-stoichiometric composition in a hydrogen atmosphere. The third is to coat a conductive layer, reduced titanium dioxide, on an insulating core such as alumina. Highly conductive powders have been produced by all these processes. The conductivity of powder compacts ranged between 10-2 and 10° S/cm. A novel doping process was developed. All samples were doped by a solid-vapor reaction instead of a solid state reaction. Titanium dioxide was doped with alkali metals such as Na or Li in this study. The alkali metal atom contributes an electron to the host material (TiO2), which then creates Ti 3+ ion. The conductivity was enhanced by creating the donor level due to the presence of these Ti3+ ions. The conductivity of those alkali doped titanium oxides was dependent on the doping level and charge mobility. Non-stoichiometric titanium oxides were produced by reduction of titanium dioxide in a hydrogen atmosphere at 800°C to 1000°C for 2 to 6 hours. The reduced titanium oxides showed better stability with respect to conductivity at ambient condition when compared with the Na or Li doped samples. Conductive coatings were prepared by coating titanium precursors on insulating core materials like SiO2, Al2O3 or mica. The titania coating was made by hydrolysis of titanyl sulfate (TiOSO 4) followed by a reduction procedure to form reduced titanium oxide. The reduced titanium oxides are highly conductive. A uniform coating of titanium oxides on alumina cores was successfully produced. The conductivity of coated powder composites was a function of coating quantity and hydrolysis reaction temperature. The conductivity of the powder as a function of structure, composition, temperature, frequency and

  13. Conditions for Aeronomic Applicability of the Classical Electron Heat Conduction Formula

    NASA Technical Reports Server (NTRS)

    Cole, K. D.; Hoegy, W. R.

    1998-01-01

    Conditions for the applicability of the classical formula for heat conduction in the electrons in ionized gas are investigated. In a fully ionised gas ( V(sub en) much greater than V(sub ei)), when the mean free path for electron-electron (or electron-ion) collisions is much larger than the characteristic thermal scale length of the observed system, the conditions for applicability break down. In the case of the Venus ionosphere this breakdown is indicated for a large fraction of the electron temperature data from altitudes greater than 180 km, for electron densities less than 10(exp 4)/cc cm. In a partially ionised gas such that V(sub en) much greater than V(sub ei) there is breakdown of the formula not only when the mean free path of electrons greatly exceeds the thermal scale length, but also when the gradient of neutral particle density exceeds the electron thermal gradient. It is shown that electron heat conduction may be neglected in estimating the temperature of joule heated electrons by observed strong 100 Hz electric fields when the conduction flux is limited by the saturation flux. The results of this paper support our earlier aeronomical arguments against the hypothesis of planetary scale whistlers for the 100 Hz electric field signal. In turn this means that data from the 100 Hz signal may not be used to support the case for lightning on Venus.

  14. Control of thermal conductivity with species mass in transition-metal dichalcogenides

    NASA Astrophysics Data System (ADS)

    Thomas, Iorwerth O.; Srivastava, G. P.

    2018-04-01

    In this paper, we examine how the behaviour of the thermal conductivity of bulk and monolayer transition-metal dichalcogenides XY2 in their 2-H form can be controlled with different choices of cation and anion masses. We employ a semi-ab-initio approach, which combines first-principles phonon eigensolutions, the elastic anharmonic Hamiltonian for phonon-phonon interactions, a quasi-harmonic scheme for the temperature-dependent Grüneisen's constant, and a relaxation-time solution of the Boltzmann transport equation. Our results confirm an earlier finding [Gu and Yang, Appl. Phys. Lett. 105, 131903 (2014)] that the thermal conductivity of 2-H MoS2 is lower than that of 2-H WS2 contrary to what would be expected from the relative masses of Mo and W and the relative stiffnesses of both compounds. In addition to confirming this anomaly as a result of the larger acoustic optical gap of WS2 relative to that of MoS2, it is found that where one constituent species is fixed, more profound changes on the thermal conductivity occur for different anion masses than for different cation masses. We explain how these behaviours arise from the dispersion relations of each compound and the anharmonic interactions of phonon modes, and its connection with the relative masses of the constituent species. This finding provides useful insight into which 2-H dichalcogenides might be suitable for which thermal applications.

  15. Optical studies of the charge localization and delocalization in conducting polymers

    NASA Astrophysics Data System (ADS)

    Kim, Youngmin

    A systematic charge transport study on the thermochromism of polyaniline (PAN) doped with a plasticizing dopant, and on a field effect device using conducting poly (3,4-ethylenedioxythiophene) (PEDOT) as its active material, was made at optical (20--45,000 cm-1) frequencies to probe the charge localization and delocalization phenomena and the insulator to metal transition (IMT) in the inhomogeneous conducting polymer system. Temperature dependent reflectance [20--8000 cm -1 (2.5 meV--1eV)] of the PAN sample, together with absorbance and do transport study done by Dr. Pron at the Laboratoire de Physique des Metaux Synthetiques in Grenoble, France, shows spectral weight loss in the infrared region but the reflectance in the very low frequency (below 100 cm-1) remains unaffected. There are two localization transitions. The origin of the 200 K localization transition that affect >˜15% of the electrons is the glass transition emanating from the dopants. The transition principally affects the IR response in the range of 200--8000 cm -1. The low temperature (<75K) localization transition affects the few electrons that provide the high conductivity. It is suggested that these electrons are localized by disorder at the lowest temperature and become delocalized through phonon induced delocalization as the temperature increases to 75K. It is noted that this temperature is typical of a Debye temperature in many organic materials. The thermocromism is attributed to the weak localization to strong localization transition through the glass transition temperature. Below the glass transition temperature (Tg), the lattice is "frozen" in configuration that reduces the charge delocalization and lead to cause increase of strongly localized polarons. Time variation of source-drain current, real-time IR reflectance [20--8000 cm-1 (2.5 meV--1eV)] modulation, and real-time UV/VIS/NIR absorbance [380--2400 nm (0.5--3.3 eV)] modulation were measured to investigate the field induced charge

  16. Comparative studies of the structure, morphology and electrical conductivity of polyaniline weakly doped with chlorocarboxylic acids

    NASA Astrophysics Data System (ADS)

    Gmati, Fethi; Fattoum, Arbi; Bohli, Nadra; Dhaoui, Wadia; Belhadj Mohamed, Abdellatif

    2007-08-01

    We report the results of studies on two series of polyaniline (PANI), doped with dichloroacetic (DCA) and trichloroacetic (TCA) acids, respectively, at various doping rates and obtained by the in situ polymerization method. Samples were characterized by x-ray diffraction, scanning electron microscopy and conductivity measurements. The direct current (dc) and alternating current (ac) electrical conductivities of PANI salts have been investigated in the temperature range 100-310 K and frequency range 7-106 Hz. The results of this study indicate better chain ordering and higher conductivity for PANI doped with TCA. The dc conductivity of all samples is suitably fitted to Mott's three-dimensional variable-range hopping (VRH) model. Different Mott parameters such as characteristic temperature T0, density of states at the Fermi level (N(EF)), average hopping energy (W) and the average hopping distance (R) have been evaluated. The dependence of such values on the dopant acid used is discussed. At high frequencies, the ac conductivity follows the power law σac(ω,T) = A(T)ωs(T,ω), which is characteristic for charge transport in disordered materials by hopping or tunnelling processes. The observed increase in the frequency exponent s with temperature suggests that the small-polaron tunnelling model best describes the dominant ac conduction mechanism. A direct correlation between conductivity, structure and morphology was obtained in our systems.

  17. How to conduct a high-quality original study on a diagnostic research topic.

    PubMed

    Yao, Xiaomei; Vella, Emily

    2017-09-01

    As health research methodologists and journal reviewers, we noticed that the methodological rigor of many publications on diagnostic or prognostic topics in the medical literature could be improved. We present a concise and clear series of reviews to help clinicians and health researchers to master the basic key components of how to conduct a high-quality original study or systematic review on a diagnostic or prognostic research topic from a methodological perspective. This is the first review of the series, which focuses on how to conduct a high-quality diagnostic study. We are introducing four aspects: clarifying the objectives; generating an appropriate research question; planning the study design; and reporting and analyzing data. This review highlights that diagnostic test accuracy outcomes are surrogates for patient outcomes, a diagnostic test has three roles, the "PIRO" components should be included in a diagnostic research question, a new study should be registered, multiple index tests can be compared in one study, and prevalence affects test accuracy outcomes. This review also emphasizes reporting any thresholds, calculating sample size, and performing a two-by-three table to calculate diagnostic outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Comparing the Similarity of Responses Received from Studies in Amazon’s Mechanical Turk to Studies Conducted Online and with Direct Recruitment

    PubMed Central

    Bartneck, Christoph; Duenser, Andreas; Moltchanova, Elena; Zawieska, Karolina

    2015-01-01

    Computer and internet based questionnaires have become a standard tool in Human-Computer Interaction research and other related fields, such as psychology and sociology. Amazon’s Mechanical Turk (AMT) service is a new method of recruiting participants and conducting certain types of experiments. This study compares whether participants recruited through AMT give different responses than participants recruited through an online forum or recruited directly on a university campus. Moreover, we compare whether a study conducted within AMT results in different responses compared to a study for which participants are recruited through AMT but which is conducted using an external online questionnaire service. The results of this study show that there is a statistical difference between results obtained from participants recruited through AMT compared to the results from the participant recruited on campus or through online forums. We do, however, argue that this difference is so small that it has no practical consequence. There was no significant difference between running the study within AMT compared to running it with an online questionnaire service. There was no significant difference between results obtained directly from within AMT compared to results obtained in the campus and online forum condition. This may suggest that AMT is a viable and economical option for recruiting participants and for conducting studies as setting up and running a study with AMT generally requires less effort and time compared to other frequently used methods. We discuss our findings as well as limitations of using AMT for empirical studies. PMID:25876027

  19. Note: Optimization of the numerical data analysis for conductivity percolation studies of drying moist porous systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moscicki, J. K.; Sokolowska, D.; Dziob, D.

    2014-02-15

    A simplified data analysis protocol, for dielectric spectroscopy use to study conductivity percolation in dehydrating granular media is discussed. To enhance visibility of the protonic conductivity contribution to the dielectric loss spectrum, detrimental effects of either low-frequency dielectric relaxation or electrode polarization are removed. Use of the directly measurable monofrequency dielectric loss factor rather than estimated DC conductivity to parameterize the percolation transition substantially reduces the analysis work and time.

  20. Studies on a.c. conductivity behaviour of milled carbon fibre reinforced epoxy gradient composites

    NASA Astrophysics Data System (ADS)

    Nigrawal, Archana; Sharma, Arun Kumar; Ojha, Pragya

    2018-05-01

    Temperature and frequency dependence of a.c. conductivity (σa.c) of milled carbon fibre (MCF) reinforced epoxy gradient composites has been studied in a wide temperature (30 to 150°C) and frequency range (1 to 10kHz). It is observed that the ac conductivity of composites increases with increase in temperature. Activation energy decreases from 0.55 eV to 0.43 eV on increase of MCF content from 0.45to 1.66 Vol%.

  1. The two faces of selective memory retrieval: Earlier decline of the beneficial than the detrimental effect with older age.

    PubMed

    Aslan, Alp; Schlichting, Andreas; John, Thomas; Bäuml, Karl-Heinz T

    2015-12-01

    Recent work with young adults has shown that, depending on study context access, selective memory retrieval can both impair and improve recall of other memories (Bäuml & Samenieh, 2010). Here, we investigated the 2 opposing effects of selective retrieval in older age. In Experiment 1, we examined 64 younger (20-35 years) and 64 older participants (above 60 years), and manipulated study context access using list-method directed forgetting. Whereas both age groups showed a detrimental effect of selective retrieval on to-be-remembered items, only younger but not older adults showed a beneficial effect on to-be-forgotten items. In Experiment 2, we examined 112 participants from a relatively wide age range (40-85 years), and manipulated study context access by varying the retention interval between study and test. Overall, a detrimental effect of selective retrieval arose when the retention interval was relatively short, but a beneficial effect when the retention interval was prolonged. Critically, the size of the beneficial but not the detrimental effect of retrieval decreased with age and this age-related decline was mediated by individuals' working memory capacity, as measured by the complex operation span task. Together, the results suggest an age-related dissociation in retrieval dynamics, indicating an earlier decline of the beneficial than the detrimental effect of selective retrieval with older age. (c) 2015 APA, all rights reserved).

  2. Community Interactive Research Workshop Series: Community Members Engaged as Team Teachers to Conduct Research.

    PubMed

    Nguyen-Truong, Connie Kim; Tang, Joannie; Hsiao, Chiao-Yun

    2017-01-01

    Vietnamese women are diagnosed with cervical cancer at twice the rate of non-Hispanic White women and the highest compared to Chinese, Filipino, Korean, and Japanese women. ἀ e Vietnamese Women's Health Project, a community-based participatory research partnership, was developed to address this concern. In earlier studies, community members received research training. To describe how we developed an innovative curricular research training framework. Community members developed their own learning goals and activities, taught alongside a nurse scientist, and participated in a community interactive research workshop series. Popular education principles were used to guide team teaching. Topics, learning goals, lesson plans, and an evaluation w ere de veloped t ogether. ἀ ree, 4 -5.5 h our workshops were hosted. Topics included qualitative research, art of hearing data, reflexivity, analysis, validity, and dissemination. Community members and a nurse scientist co-constructed knowledge through participatory methods. ἀe workshops ran concurrent to the study timeline to inform community members' research activities and vice versa. A range from 8 to 20 participants attended the workshops, of which six community members were team teachers and three facilitated at each workshop. In an evaluation, team teachers reported workshop strengths: an empathetic and trusting learn ing environment, a sense of ownership in learning, a greater under standing of roles in research partnerships, and a feel ing of safety to conduct research with academic investigators. Academic investigators need to be aware that co-constructing knowledge is foundational to long-term sustainability of community-based participatory research partnership (CBPR) partnerships, but requires building team capacity to conduct research collaboratively.

  3. Risk of Suicide Attempt among Adolescents with Conduct Disorder: A Longitudinal Follow-up Study.

    PubMed

    Wei, Han-Ting; Lan, Wen-Hsuan; Hsu, Ju-Wei; Bai, Ya-Mei; Huang, Kai-Lin; Su, Tung-Ping; Li, Cheng-Ta; Lin, Wei-Chen; Chen, Tzeng-Ji; Chen, Mu-Hong

    2016-10-01

    To assess the independent or comorbid effect of conduct and mood disorders on the risk of suicide. The Taiwan National Health Insurance Research Database was used to derive data for 3711 adolescents aged 12-17 years with conduct disorder and 14 844 age- and sex-matched controls between 2001 and 2009. The participants were followed up to the end of 2011, and those who attempted suicide during the follow-up period were identified. Adolescents with conduct disorder had a higher incidence of suicide (0.9% vs 0.1%; P <.001) and attempted suicide at a younger age (17.38 ± 2.04 vs 20.52 ± 1.70 years of age) than did the controls. The Cox proportional hazards regression model, after adjustment for demographic data and psychiatric comorbidities, determined that conduct disorder was an independent risk factor for subsequent suicide attempts (hazard ratio, 5.17; 95% CI, 2.29-11.70). The sensitivity after those with other psychiatric comorbidities were excluded revealed a consistent finding (hazard ratio, 10.32; 95% CI, 3.71-28.71). Adolescents with conduct disorder had an increased risk of suicide attempts over the next decade. Future studies are required to clarify the underlying pathophysiology and elucidate whether prompt intervention for conduct disorder could reduce this risk. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Electrical conductivity of activated carbon-metal oxide nanocomposites under compression: a comparison study.

    PubMed

    Barroso-Bogeat, A; Alexandre-Franco, M; Fernández-González, C; Macías-García, A; Gómez-Serrano, V

    2014-12-07

    From a granular commercial activated carbon (AC) and six metal oxide (Al2O3, Fe2O3, SnO2, TiO2, WO3 and ZnO) precursors, two series of AC-metal oxide nanocomposites were prepared by wet impregnation, oven-drying at 120 °C, and subsequent heat treatment at 200 or 850 °C in an inert atmosphere. Here, the electrical conductivity of the resulting products was studied under moderate compression. The influence of the applied pressure, sample volume, mechanical work, and density of the hybrid materials was thoroughly investigated. The DC electrical conductivity of the compressed samples was measured at room temperature by the four-probe method. Compaction assays suggest that the mechanical properties of the nanocomposites are largely determined by the carbon matrix. Both the decrease in volume and the increase in density were relatively small and only significant at pressures lower than 100 kPa for AC and most nanocomposites. In contrast, the bulk electrical conductivity of the hybrid materials was strongly influenced by the intrinsic conductivity, mean crystallite size, content and chemical nature of the supported phases, which ultimately depend on the metal oxide precursor and heat treatment temperature. The supported nanoparticles may be considered to act as electrical switches either hindering or favouring the effective electron transport between the AC cores of neighbouring composite particles in contact under compression. Conductivity values as a rule were lower for the nanocomposites than for the raw AC, all of them falling in the range of semiconductor materials. With the increase in heat treatment temperature, the trend is toward the improvement of conductivity due to the increase in the crystallite size and, in some cases, to the formation of metals in the elemental state and even metal carbides. The patterns of variation of the electrical conductivity with pressure and mechanical work were slightly similar, thus suggesting the predominance of the pressure

  5. Nanoscale electrical property studies of individual GeSi quantum rings by conductive scanning probe microscopy.

    PubMed

    Lv, Yi; Cui, Jian; Jiang, Zuimin M; Yang, Xinju

    2012-11-29

    The nanoscale electrical properties of individual self-assembled GeSi quantum rings (QRs) were studied by scanning probe microscopy-based techniques. The surface potential distributions of individual GeSi QRs are obtained by scanning Kelvin microscopy (SKM). Ring-shaped work function distributions are observed, presenting that the QRs' rim has a larger work function than the QRs' central hole. By combining the SKM results with those obtained by conductive atomic force microscopy and scanning capacitance microscopy, the correlations between the surface potential, conductance, and carrier density distributions are revealed, and a possible interpretation for the QRs' conductance distributions is suggested.

  6. A Fractal Study on the Effective Thermal Conductivity of Porous Media

    NASA Astrophysics Data System (ADS)

    Qin, X.; Cai, J.; Wei, W.

    2017-12-01

    Thermal conduction in porous media has steadily received attention in science and engineering, for instance, exploiting and utilizing the geothermal energy, developing the oil-gas resource, ground water flow in hydrothermal systems and investigating the potential host nuclear wastes, etc. The thermal conductivity is strongly influenced by the microstructure features of porous media. In this work, based on the fractal characteristics of the grains, a theoretical model of effective thermal conductivity is proposed for saturated and unsaturated porous media. It is found that the proposed effective thermal conductivity solution is a function of geometrical parameters of porous media, such as the porosity, fractal dimension of granular matrix and the thermal conductivity of the grains and pore fluid. The model predictions are compared with existing experimental data and the results show that they are in good agreement with existing experimental data. The proposed model may provide a better understanding of the physical mechanisms of thermal transfer in porous media than conventional models.

  7. Giant-Magnetoresistance(GMR) Siegel KEY FIRST Experimental Discovery Decade-Earlier PRE-``Fert"-``Gruenberg" in Nuc"el"ar ``Super"alloys: Science?;``SEANCE!!!; Ethics?; SHMETHICS!!!

    NASA Astrophysics Data System (ADS)

    Hoffman, R.; Siegel, E.

    2010-03-01

    (So MIScalled) ``Fert"-``Grunberg"[PRL(1988;1989)] GMR 2007 physics Nobel/Wolf/Japan-Prizes VS. decade-earlier(1973-1977) KEY FIRST Siegel at:Westin"kl"ouse/PSEG/IAEA/ABB[google:``Martin Ebner"(94-04) in financial media]/Vattenfall/Wallenbergs/nuc"el"ar-DoE Labs[at flickr.com, search on ``Giant- Magnotoresistance''; find: Intl.Conf.Mag.Alloys & Oxides(ICMAO), Haifa(Aug./1977); J.Mag.Mag.Mtls,(JMMM)7,312(1978)``unavailable: not yet scanned''/modified(last R(H) GMR Figs(7;8) deleted!!!) on JMMM/Reed-Elsevier website until 7/29/08 conveniently one- half-year after last (Nobel)award(12/2007); conveniently effectively deleted!!!; google: ``If Leaks Could Kill''; many APS/MRS Mtgs(1970s)<<<1988/1989] decade-earlier GMR: (1978)<<< (1988); 1988-1978 =10 years = one full decadeprecedence!!!] first experimental discovery in (so MIScalled) ``super''alloys [182/82, Hastelloy-X, 600, 690(!!!), Stainless-Steels: ANY/ALL!!!] generic endemic Wigner's[JAP,17,857(1946)]- disease/Ostwald-ripening/spinodal-decomposition/overageing- embrittlement/ thermo-mechanical-INstability!

  8. The evaluation of clinical and cost outcomes associated with earlier initiation of insulin in patients with type 2 diabetes mellitus.

    PubMed

    Smolen, Harry J; Murphy, Daniel R; Gahn, James C; Yu, Xueting; Curtis, Bradley H

    2014-09-01

    The treatment for patients with type 2 diabetes mellitus (T2DM) follows a stepwise progression. As a treatment loses its effectiveness, it is typically replaced with a more complex and frequently more costly treatment. Eventually this progression leads to the use of basal insulin typically with concomitant treatments (e.g., metformin, a GLP-1 RA [glucagon-like peptide-1 receptor agonist], a TZD [thiazolidinedione] or a DPP-4i [dipeptidyl peptidase 4 inhibitor]) and, ultimately, to basal-bolus insulin in some forms. As the cost of oral antidiabetics (OADs) and noninsulin injectables have approached, and in some cases exceeded, the cost of insulin, we reexamined the placement of insulin in T2DM treatment progression. Our hypothesis was that earlier use of insulin produces clinical and cost benefits due to its superior efficacy and treatment scalability at an acceptable cost when considered over a 5-year period. To (a) estimate clinical and payer cost outcomes of initiating insulin treatment for patients with T2DM earlier in their treatment progression and (b) estimate clinical and payer cost outcomes resulting from delays in escalating treatment for T2DM when indicated by patient hemoglobin A1c levels. We developed a Monte Carlo microsimulation model to estimate patients reaching target A1c, diabetes-related complications, mortality, and associated costs under various treatment strategies for newly diagnosed patients with T2DM. Treatment efficacies were modeled from results of randomized clinical trials, including the time and rate of A1c drift. A typical treatment progression was selected based on the American Diabetes Association and the European Association for the Study of Diabetes guidelines as the standard of care (SOC). Two treatment approaches were evaluated: two-stage insulin (basal plus antidiabetics followed by biphasic plus metformin) and single-stage insulin (biphasic plus metformin). For each approach, we analyzed multiple strategies. For each analysis

  9. A Novel Technique for Clinical Assessment of Laryngeal Nerve Conduction: Normal and Abnormal Results

    PubMed Central

    Sulica, Lucian; Carey, Bridget; Branski, Ryan C.

    2014-01-01

    Objectives/Hypothesis To describe a novel conduction study of the laryngeal nerves, including normal values and abnormal findings. Study Design Prospective nonrandomized. Methods Seventeen healthy adult volunteers, as well as three patients with clinically identified laryngeal neuropathy, underwent low-level brief electrical stimulation of the laryngeal mucosa by means of a wire inserted via a transnasal flexible laryngoscope. Bilateral hookwire electrodes recorded the result in the laryngeal adductor muscles. Results This study yields an early response ipsilateral to the side of stimulation (LR1), which is uniform and consistent (right 5 13.2 6 0.80 msec; left 5 15.2 6 1.20 msec), and late bilateral responses (ipsilateral LR2 [LR2i] and contralateral LR2 [LR2c]), which exhibit greater variation in latency and morphology (right LR2i 5 50.5 6 3.38 msec; left LR2i 5 52.2 msec; right LR2c 5 50.7 6 4.26; left LR2c 5 50.6 6 4.07). Findings in abnormal patients differ significantly from normal, consistent with the distribution of neuropathy. Conclusions We describe a novel, clinically applicable conduction study of laryngeal nerves. Normative electrodiagnostic values and variations of the reflex responses of the laryngeal adductor muscles in response to irritative stimulation of the laryngeal mucosa (Laryngeal Closure Reflex) are proposed. By enabling the determination of electrophysiological parameters of the superior laryngeal and recurrent laryngeal branches of cranial nerve X (CN X), this procedure, which is used as an adjunct to laryngeal electromyography, may provide earlier and more accurate information regarding the extent and grade of nerve injury. Because injury grade relates directly to prognosis, the information derived from this test may have clinical relevance in determining optimal treatment. Level of Evidence 4. PMID:23835889

  10. Conduct Disorder and Neighborhood Effects.

    PubMed

    Jennings, Wesley G; Perez, Nicholas M; Reingle Gonzalez, Jennifer M

    2018-05-07

    There has been a considerable amount of scholarly attention to the relationship between neighborhood effects and conduct disorder, particularly in recent years. Having said this, it has been nearly two decades since a comprehensive synthesis of this literature has been conducted. Relying on a detailed and comprehensive search strategy and inclusion criteria, this article offers a systematic and interdisciplinary review of 47 empirical studies that have examined neighborhood effects and conduct disorder. Described results suggest that there are generally robust linkages between adverse neighborhood factors and conduct disorder and externalizing behavior problems, as 67 of the 93 (72.04%) effect sizes derived from these studies yielded statistically significant neighborhood effects. The review also identifies salient mediating and moderating influences. It discusses study limitations and directions for future research as well.

  11. Issues in Conducting Epidemiologic Research Among Elders: Lessons From The MOBILIZE Boston Study

    PubMed Central

    Kelsey, Jennifer L.; Kiel, Douglas P.; Roman, Anthony M.; Cupples, L. Adrienne; Freeman, Marcie B.; Jones, Richard N.; Hannan, Marian T.; Leveille, Suzanne G.; Gagnon, Margaret M.; Lipsitz, Lewis A.

    2008-01-01

    Conducting research in elderly populations is important, but challenging. In this paper, the authors describe specific challenges that have arisen and solutions that have been used in carrying out The MOBILIZE Boston Study, a community-based, prospective cohort study in Massachusetts focusing on falls among 765 participants aged 70 years or older enrolled during 2005–2007. To recruit older individuals, face-to-face interactions are more effective than less personal approaches. Use of a board of community leaders facilitated community acceptance of the research. Establishing eligibility for potential participants required several interactions, so resources must be anticipated in advance. Assuring a safe and warm environment for elderly participants and offering a positive experience are a vital priority. Adequate funding, planning, and monitoring are required to provide transportation and a fully accessible environment in which to conduct study procedures as well as to select personnel highly skilled in interacting with elders. It is hoped that this paper will encourage and inform future epidemiologic research in this important segment of the population. PMID:18953059

  12. Issues in conducting epidemiologic research among elders: lessons from the MOBILIZE Boston Study.

    PubMed

    Samelson, Elizabeth J; Kelsey, Jennifer L; Kiel, Douglas P; Roman, Anthony M; Cupples, L Adrienne; Freeman, Marcie B; Jones, Richard N; Hannan, Marian T; Leveille, Suzanne G; Gagnon, Margaret M; Lipsitz, Lewis A

    2008-12-15

    Conducting research in elderly populations is important, but challenging. In this paper, the authors describe specific challenges that have arisen and solutions that have been used in carrying out The MOBILIZE Boston Study, a community-based, prospective cohort study in Massachusetts focusing on falls among 765 participants aged 70 years or older enrolled during 2005-2007. To recruit older individuals, face-to-face interactions are more effective than less personal approaches. Use of a board of community leaders facilitated community acceptance of the research. Establishing eligibility for potential participants required several interactions, so resources must be anticipated in advance. Assuring a safe and warm environment for elderly participants and offering a positive experience are a vital priority. Adequate funding, planning, and monitoring are required to provide transportation and a fully accessible environment in which to conduct study procedures as well as to select personnel highly skilled in interacting with elders. It is hoped that this paper will encourage and inform future epidemiologic research in this important segment of the population.

  13. The study of electrical conductivity of DNA molecules by scanning tunneling spectroscopy

    NASA Astrophysics Data System (ADS)

    Sharipov, T. I.; Bakhtizin, R. Z.

    2017-10-01

    An interest to the processes of charge transport in DNA molecules is very high, due to perspective of their using in nanoelectronics. The original sample preparation for studying electrical conductivity of DNA molecules by scanning tunneling spectroscopy has been proposed and tested. The DNA molecules immobilized on gold surface have been imaged clearly and their current-voltage curves have been measured.

  14. Conductance of kinked nanowires

    NASA Astrophysics Data System (ADS)

    Cook, B. G.; Varga, K.

    2011-01-01

    The conductance properties of kinked nanowires are studied by first-principles transport calculations within a recently developed complex potential framework. Using prototypical examples of monoatomic Au chains as well as small diameter single-crystalline silicon nanowires we show that transmission strongly depends on the kink geometry and one can tune the conductance properties by the kink angle and other geometrical factors. In the case of a silicon nanowire the presence of a kink drastically reduces the conductance.

  15. XPS/NEXAFS spectroscopic and conductance studies of glycine on AlGaN/GaN transistor devices

    NASA Astrophysics Data System (ADS)

    Myers, Matthew; Khir, Farah Liyana Muhammad; Home, Michael A.; Mennell, Christopher; Gillbanks, Jeremy; Tadich, Anton; Baker, Murray V.; Nener, Brett D.; Parish, Giacinta

    2018-03-01

    We report on a study using a combination of XPS/NEXAFS and conductivity measurements to develop a fundamental understanding of how dipolar molecules interact with the heterostructure device surface and affect the device conductivity of AlGaN/GaN heterostructure-based transistors. In such structures, which are increasingly being investigated for chemical and biological sensing, a 2-dimensional electron gas spontaneously forms at the layer interface that is sensitive to the charge characteristics of the exposed surface. Glycine, chosen for this study because it is the simplest of the amino acids and is known to form a zwitterionic configuration when stabilized through intermolecular interactions, was evaporated under ultra-high vacuum conditions onto the device surface and subsequently both XPS/NEXAFS and conductivity measurements were conducted. NEXAFS spectra show a preferential orientation for the Glycine molecules on the surface and evidence for both neutral and zwitterionic species on the surface. In situ conductivity measurements suggest that the negatively charged carboxylate group is closest to the surface. These results are a unique and pivotal contribution to the previous and at times conflicting literature on the zwitterionic nature of Glycine.

  16. Thermal conductivity study of warm dense matter by differential heating on LCLS and Titan

    NASA Astrophysics Data System (ADS)

    Hill, M.; McKelvey, A.; Jiang, S.; Shepherd, R.; Hau-Riege, S.; Whitley, H.; Sterne, P.; Hamel, S.; Collins, G.; Ping, Y.; Brown, C.; Floyd, E.; Fyrth, J.; Hoarty, D.; Hua, R.; Bailly-Grandvaux, M.; Beg, F.; Cho, B.; Kim, M.; Lee, J.; Lee, H.; Galtier, E.

    2017-10-01

    A differential heating platform has been developed for thermal conduction study, where a temperature gradient is induced and subsequent heat flow is probed by time-resolved diagnostics. Multiple experiment using this platform have been carried out at LCLS-MEC and Titan laser facilities for warm dense Al, Fe, amorphous carbon and diamond. Two single-shot time-resolved diagnostics are employed, SOP (streaked optical pyrometry) for surface temperature and FDI (Fourier Domain Interferometry) for surface expansion. Both diagnostics provided excellent data to constrain release equation-of-state (EOS) and thermal conductivity. Data sets with varying target thickness and comparison between simulations with different thermal conductivity models are presented. This work was performed under DOE contract DE-AC52-07NA27344 with support from DOE OFES Early Career program and LLNL LDRD program.

  17. Impact of applying the more stringent validation criteria of the revised European Society of Hypertension International Protocol 2010 on earlier validation studies.

    PubMed

    Stergiou, George S; Karpettas, Nikos; Atkins, Neil; O'Brien, Eoin

    2011-04-01

    Since 2002 when the European Society of Hypertension International Protocol (ESH-IP) was published it has become the preferred protocol for validating blood pressure monitors worldwide. In 2010, a revised version of the ESH-IP with more stringent criteria was published. This study assesses the impact of applying the revised ESH-IP criteria. A systematic literature review of ESH-IP studies reported between 2002 and 2010 was conducted. The impact of applying the ESH-IP 2010 criteria retrospectively on the data reported in these studies was investigated. The performance of the oscillometric devices in the last decade was also investigated on the basis of the ESH-IP criteria. Among 119 published studies, 112 with sufficient data were analyzed. According to ESH-IP 2002, the test device failed in 19 studies, whereas by applying the ESH-IP 2010 criteria in 28 additional studies increased the failure rate from 17 to 42%. Of these 28 studies, in 20 (71%) the test device failed at part 1 (accuracy per measurement) and in 22 (79%) at part 2 (accuracy per subject). Most of the failures involved the '5 mmHg or less' criterion. In the last decade there has been a consistent trend toward improved performance of oscillometric devices assessed on the basis of the ESH-IP criteria. This retrospective analysis shows that the stricter revised ESH-IP 2010 criteria will noticeably increase the failure rate of devices being validated. Oscillometric devices are becoming more accurate, and the revised ESH-IP by acknowledging this trend will allow more accurate devices to enter the market.

  18. Conducting a multicentre and multinational qualitative study on patient transitions.

    PubMed

    Johnson, Julie K; Barach, Paul; Vernooij-Dassen, Myrra

    2012-12-01

    A multicentre, multinational research study requires careful planning and coordination to accomplish the aims of the study and to ensure systematic and rigorous examination of all project methods and data collected. The aim of this paper is to describe the approach we used during the HANDOVER Project to develop a multicentre, multinational research project for studying transitions of patient care while creating a community of practice for the researchers. We highlight the process used to assure the quality of a multicentre qualitative study and to create a codebook for data analysis as examples of attending to the community of practice while conducting rigorous qualitative research. Essential elements for the success of this multinational, multilanguage research project included recruiting a strong research team, explicit planning for decision-making processes to be used throughout the project, acknowledging the differences among the study settings and planning the protocols to capitalise upon those differences. Although not commonly discussed in reports of large research projects, there is an underlying, concurrent stream of activities to develop a cohesive team that trusts and respects one another's skills and that engage independent researchers in a group process that contributes to achieving study goals. We discuss other lessons learned and offer recommendations for other teams planning multicentre research.

  19. Coping and emotional distress during acute hospitalization in older persons with earlier trauma: the case of Holocaust survivors.

    PubMed

    Kimron, Lee; Cohen, Miri

    2012-06-01

    Older persons with earlier trauma are often more vulnerable to stresses of old age. To examine the levels of emotional distress in relation to cognitive appraisal of acute hospitalization and coping strategies in Holocaust survivors compared with an age- and education-matched group of elderly persons without Holocaust experience. This is a cross-sectional study of 63 Holocaust survivors, 65 years and older, hospitalized for an acute illness, and 57 age-, education- and hospital unit-matched people without Holocaust experience. Participants completed appraisal and coping strategies (COPE) questionnaires, and the brief symptoms inventory (BSI-18). Holocaust survivors reported higher levels of emotional distress, appraised the hospitalization higher as a threat and lower as a challenge, and used more emotion-focused and less problem-focused or support-seeking coping strategies than the comparison group. Study variables explained 65% of the variance of emotional distress; significant predictors of emotional distress in the final regression model were not having a partner and more use of emotion-focused coping. The latter mediated the relation of group variable and challenge appraisal to emotional distress. Health professionals must be aware of the potential impact of the hospital environment on the survivors of Holocaust as well as survivors of other trauma. Being sensitive to their specific needs may reduce the negative impact of hospitalization.

  20. Gas release and conductivity modification studies

    NASA Technical Reports Server (NTRS)

    Linson, L. M.; Baxter, D. C.

    1979-01-01

    The behavior of gas clouds produced by releases from orbital velocity in either a point release or venting mode is described by the modification of snowplow equations valid in an intermediate altitude regime. Quantitative estimates are produced for the time dependence of the radius of the cloud, the average internal energy, the translational velocity, and the distance traveled. The dependence of these quantities on the assumed density profile, the internal energy of the gas, and the ratio of specific heats is examined. The new feature is the inclusion of the effect of the large orbital velocity. The resulting gas cloud models are used to calculate the characteristics of the field line integrated Pedersen conductivity enhancements that would be produced by the release of barium thermite at orbital velocity in either the point release or venting modes as a function of release altitude and chemical payload weight.

  1. Assessment of risk factors for earlier onset of sporadic Alzheimer's disease dementia.

    PubMed

    de Oliveira, Fabricio Ferreira; Bertolucci, Paulo Henrique Ferreira; Chen, Elizabeth Suchi; Smith, Marilia Cardoso

    2014-01-01

    Pharmacological treatment has mild effects for patients with Alzheimer's disease dementia (AD); therefore, the search for modifiable risk factors is an important challenge. Though risk factors for AD are widely recognized, elements that influence the time of dementia onset have not been comprehensively reported. We aimed to investigate which risk factors might be related to the age of onset of AD in a sample of patients with highly variable educational levels, taking into account the Framingham risk scoring as the sole measure of vascular risk. We included 209 consecutive late-onset AD patients to find out which factors among educational levels, coronary heart disease risk estimated by way of Framingham risk scores, history of head trauma or depression, surgical procedures under general anesthesia, family history of neurodegenerative diseases, gender, marital status and APOE haplotypes might be related to the age of dementia onset in this sample of patients with low mean schooling. Mean age of AD onset was 73.38±6.5 years old, unaffected by schooling or family history of neurodegenerative diseases. Patients who were APOE-ε4 carriers, married, or with history of depression, had earlier onset of AD, particularly when they were women. Coronary heart disease risk was marginally significant for later onset of AD. APOE haplotypes, marital status and history of depression were the most important factors to influence the age of AD onset in this sample. While midlife cerebrovascular risk factors may increase incidence of AD, they may lead to later dementia onset when present in late life.

  2. Study of the Kinetics of an S[subscript N]1 Reaction by Conductivity Measurement

    ERIC Educational Resources Information Center

    Marzluff, Elaine M.; Crawford, Mary A.; Reynolds, Helen

    2011-01-01

    Substitution reactions, a central part of organic chemistry, provide a model system in physical chemistry to study reaction rates and mechanisms. Here, the use of inexpensive and readily available commercial conductivity probes coupled with computer data acquisition for the study of the temperature and solvent dependence of the solvolysis of…

  3. Design a Fuzzy Rule-based Expert System to Aid Earlier Diagnosis of Gastric Cancer.

    PubMed

    Safdari, Reza; Arpanahi, Hadi Kazemi; Langarizadeh, Mostafa; Ghazisaiedi, Marjan; Dargahi, Hossein; Zendehdel, Kazem

    2018-01-01

    Screening and health check-up programs are most important sanitary priorities, that should be undertaken to control dangerous diseases such as gastric cancer that affected by different factors. More than 50% of gastric cancer diagnoses are made during the advanced stage. Currently, there is no systematic approach for early diagnosis of gastric cancer. to develop a fuzzy expert system that can identify gastric cancer risk levels in individuals. This system was implemented in MATLAB software, Mamdani inference technique applied to simulate reasoning of experts in the field, a total of 67 fuzzy rules extracted as a rule-base based on medical expert's opinion. 50 case scenarios were used to evaluate the system, the information of case reports is given to the system to find risk level of each case report then obtained results were compared with expert's diagnosis. Results revealed that sensitivity was 92.1% and the specificity was 83.1%. The results show that is possible to develop a system that can identify High risk individuals for gastric cancer. The system can lead to earlier diagnosis, this may facilitate early treatment and reduce gastric cancer mortality rate.

  4. Polymers that Conduct Electricity.

    ERIC Educational Resources Information Center

    Edelson, Edward

    1983-01-01

    Although polymers are regarded as electrical insulators, it was discovered that they can be made to conduct electricity. This discovery has opened vast new practical and theoretical areas for exploration by physicists and chemists. Research studies with these conducting polymers and charge-transfer salts as well as possible applications are…

  5. [Nationwide Survey on Informed Consent and Ethical Review at Hospitals Conducting Post-marketing Studies Sponsored by Pharmaceutical Companies].

    PubMed

    Urushihara, Hisashi; Murakami, Yuka; Matsui, Kenji; Tashiro, Shimon

    2018-01-01

     Under the Japanese drug regulatory system, post-marketing studies (PMS) must be in compliance with Good Post-marketing Study Practice (GPSP). The GPSP Ordinance lacks standards for the ethical conduct of PMSs; although only post-marketing clinical trials are subject to Good Clinical Practice. We conducted a web-based questionnaire survey on the ethical conduct of PMSs in collaboration with the Japanese Society of Hospital Pharmacists and pharmacists belonging to the Society. 1819 hospitals around Japan answered the questionnaire, of which 503 hospitals had conducted company-sponsored PMSs in 2015. 40.2% of the hospitals had obtained informed consent from participating patients in at least one PMS conducted in 2015, the majority of which was in written form. The first and second most frequent reasons for seeking informed consent in PMSs were to meet protocol requirements, followed by the requirement to meet institutional standard operational procedures and the request of the ethical review board of the hospital. Ethical review of PMSs was conducted in 251 hospitals. Despite a lack of standards for informed consent and ethical review in PMSs, a considerable number of study sites employed informed consent and ethical review for PMSs. While company policies and protocols are likely to be major determinants of the ethical conduct of PMSs, the governmental regulatory agency should also play a significant role in implementing a standardized ethical code for the conduct of PMSs.

  6. Effect of stretching on the ballistic conductance of Au nanocontacts in presence of CO: A density functional study

    NASA Astrophysics Data System (ADS)

    Sclauzero, Gabriele; Dal Corso, Andrea; Smogunov, Alexander

    2012-04-01

    CO adsorption on an Au monatomic chain is studied within density functional theory in nanocontact geometries as a function of the contact stretching. We compare the bridge and atop adsorption sites of CO, finding that the bridge site is energetically favored at all strains studied here. Atop adsorption gives rise to an almost complete suppression of the ballistic conductance of the nanocontact, while adsorption at the bridge site results in a conductance value close to 0.6G0, in agreement with previous experimental data. We show that only the bridge site can qualitatively account for the evolution of the conductance as a function of the contact stretching observed in the experimental conductance traces. The numerical discrepancy between the theoretical and experimental conductance slopes is rationalized through a simple model for the elastic response of the metallic leads. We also verify that our conductance values are not affected by the specific choice of the nanocontact geometry by comparing two different atomistic models for the tips.

  7. Practical Issues of Conducting a Q Methodology Study: Lessons Learned From a Cross-cultural Study.

    PubMed

    Stone, Teresa Elizabeth; Maguire, Jane; Kang, Sook Jung; Cha, Chiyoung

    This article advances nursing research by presenting the methodological challenges experienced in conducting a multination Q-methodology study. This article critically analyzes the relevance of the methodology for cross-cultural and nursing research and the challenges that led to specific responses by the investigators. The use of focus groups with key stakeholders supplemented the Q-analysis results. The authors discuss practical issues and shared innovative approaches and provide best-practice suggestions on the use of this flexible methodology. Q methodology has the versatility to explore complexities of contemporary nursing practice and cross-cultural health research.

  8. Synthesis and characterization of ion transport behavior in Cu2+-conducting nano composite polymer electrolyte membranes

    NASA Astrophysics Data System (ADS)

    Bala Sahu, Tripti; Sahu, Manju; Karan, Shrabani; Mahipal, Y. K.; Sahu, D. K.; Agrawal, R. C.

    2017-07-01

    Synthesis and characterization of ion transport behavior in Cu2+-conducting nano composite polymer electrolyte (NCPE) films: [90PEO: 10Cu(CF3SO3)2]  +  x CuO have been reported. NCPE films have been formed by hot-press casting technique using solid polymer electrolyte (SPE) film composition: [90PEO: 10Cu(CF3SO3)2] as 1st-phase host and nanoparticles of CuO in varying wt.(%) as 2nd-phase active filler. SPE: [90PEO: 10Cu(CF3SO3)2] was identified earlier as highest conducting film with room temperature conductivity (σ rt) ~ 3.0 x 10-6 S cm-1, which is three orders of magnitude higher than that of pure polymer host PEO with σ rt ~ 3.2  ×  10-9 S cm-1. Filler particle concentration dependent conductivity study revealed NCPE film: [90PEO: 10Cu(CF3SO3)2]  +  3%CuO as optimum conducting composition (OCC) exhibiting σ rt ~ 1.14  ×  10-5 S cm-1. Hence, by the fractional dispersal of 2nd-phase active filler into 1st-phase SPE host, σ-enhancement of approximately an order of magnitude has further been obtained. Ion transport behavior in NCPE OCC film has been characterized in terms of basic ionic parameters viz. ionic conductivity (σ), total ionic transference (t ion)/cationic (t +) numbers. Temperature dependent conductivity measurement has also been done to explain the mechanism of ion transport and to compute activation energy (E a). Materials characterization and hence, confirmation of complexation of salt in polymeric host and/or dispersal of filler particles in SPE host have been done by scanning electron microscopy (SEM), energy dispersive x-ray spectrometer (EDS), x-ray diffraction (XRD), Fourier transform infra-red (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). All-solid-state battery in the cell configuration: Cu (Anode) || SPE host/NCPE OCC film || C  +  I2  +  Electrolyte) (Cathode) has been fabricated and cell performance has been studied under two load resistances viz

  9. High hunting pressure selects for earlier birth date: Wild boar as a case study

    USGS Publications Warehouse

    Gamelon, M.; Besnard, A.; Gaillard, J.-M.; Servanty, S.; Baubet, E.; Brandt, S.; Gimenez, O.

    2011-01-01

    Exploitation by humans affects the size and structure of populations. This has evolutionary and demographic consequences that have typically being studied independent of one another. We here applied a framework recently developed applying quantitative tools from population ecology and selection gradient analysis to quantify the selection on a quantitative trait-birth date-through its association with multiple fitness components. From the long-term monitoring (22 years) of a wild boar (Sus scrofa scrofa) population subject to markedly increasing hunting pressure, we found that birth dates have advanced by up to 12 days throughout the study period. During the period of low hunting pressure, there was no detectable selection. However, during the period of high hunting pressure, the selection gradient linking breeding probability in the first year of life to birth date was negative, supporting current life-history theory predicting selection for early births to reproduce within the first year of life with increasing adult mortality. ?? 2011 The Author(s). Evolution?? 2011 The Society for the Study of Evolution..

  10. Getting started in research: designing and preparing to conduct a research study.

    PubMed

    Macfarlane, Matthew D; Kisely, Steve; Loi, Samantha; Macfarlane, Stephen; Merry, Sally; Parker, Stephen; Power, Brian; Siskind, Dan; Smith, Geoff; Looi, Jeffrey C

    2015-02-01

    To discuss common pitfalls and useful tips in designing a quantitative research study, the importance and process of ethical approval, and consideration of funding. Through careful planning, based on formulation of a research question, early career researchers can design and conduct quantitative research projects within the framework of the Scholarly Project or in their own independent projects. © The Royal Australian and New Zealand College of Psychiatrists 2014.

  11. Participants' Reactions to and Suggestions for Conducting Intimate Partner Violence Research: A Study of Rural Young Adults.

    PubMed

    Edwards, Katie M; Greaney, Kayleigh; Palmer, Kelly M

    2016-01-01

    To document rural young adults' reasons for emotional reactions to participating in intimate partner violence (IPV) research as well as to hear young adults' perspectives on how to most effectively conduct comprehensive IPV research in their rural communities. The data presented in this paper draw from 2 studies (ie, an online survey study and an in-person or telephone interview study) that included the same 16 US rural counties in New England and Appalachia. Participants, 47% of whom were in both studies, were young (age range 18-24), white (92%-94%), heterosexual (89%-90%), female (62%-68%), and mostly low to middle income. Nine percent of participants reported they were upset by the questions due to personal experiences with IPV or for other reasons not related to personal IPV experiences. Forty percent of participants reported they personally benefited from participating in the study, and they provided various reasons for this benefit. Regarding suggestions for conducting IPV research with rural young adults, participants believed that both online recruitment and online data collection methods were the best ways to engage young adults, although many participants suggested that more than 1 modality was ideal, which underscores the need for multimethod approaches when conducting research with rural young adults. These findings are reassuring to those committed to conducting research on sensitive topics with rural populations and also shed light on best practices for conducting this type of research from the voices of rural young adults themselves. © 2015 National Rural Health Association.

  12. Hopping Conduction in Polymers

    NASA Astrophysics Data System (ADS)

    Bässler, Heinz

    The concept of hopping within a Gaussian density of localized states introduced earlier to rationalize charge transport in random organic photoconductors is developed further to account for temporal features of time of flight (TOF) signals. At moderate degree of energetic disorder (σ/kT~3.5…4.5) there is a transport regime intermediate between dispersive and quasi-Gaussian type whose signatures are (i) universal TOF signals that can appear weakly dispersive despite yielding a well defined carrier mobility and (ii) an asymmetric propagator of the carrier packet yielding a time dependent diffusivity.

  13. 25 CFR 900.196 - Do covered services include the conduct of clinical studies and investigations and the provision...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Do covered services include the conduct of clinical studies and investigations and the provision of emergency services, including the operation of emergency... Claims § 900.196 Do covered services include the conduct of clinical studies and investigations and the...

  14. Structure, ionic conductivity and mobile carrier density in fast ionic conducting chalcogenide glasses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yao, Wenlong

    2006-01-01

    This thesis consists of six sections. The first section gives the basic research background on the ionic conduction mechanism in glass, polarization in the glass, and the method of determining the mobile carrier density in glass. The proposed work is also included in this section. The second section is a paper that characterizes the structure of MI + M 2S + (0.1 Ga 2S 3 + 0.9 GeS 2) (M = Li, Na, K and Cs) glasses using Raman and IR spectroscopy. Since the ionic radius plays an important role in determining the ionic conductivity in glasses, the glass formingmore » range for the addition of different alkalis into the basic glass forming system 0.1 Ga 2S 3 + 0.9 GeS 2 was studied. The study found that the change of the alkali radius for the same nominal composition causes significant structure change to the glasses. The third section is a paper that investigates the ionic conductivity of MI + M 2S + (0.1Ga 2S 3 + 0.9 GeS 2) (M = Li, Na, K and Cs) glasses system. Corresponding to the compositional changes in these fast ionic conducting glasses, the ionic conductivity shows changes due to the induced structural changes. The ionic radius effect on the ionic conductivity in these glasses was investigated. The fourth section is a paper that examines the mobile carrier density based upon the measurements of space charge polarization. For the first time, the charge carrier number density in fast ionic conducting chalcogenide glasses was determined. The experimental impedance data were fitted using equivalent circuits and the obtained parameters were used to determine the mobile carrier density. The influence of mobile carrier density and mobility on the ionic conductivity was separated. The fifth section is a paper that studies the structures of low-alkali-content Na 2S + B 2S 3 (x ≤ 0.2) glasses by neutron and synchrotron x-ray diffraction. Similar results were obtained both in neutron and synchrotron x-ray diffraction experiments. The results provide direct structural

  15. Earlier detection of breast cancer by surveillance of women at familial risk.

    PubMed

    Tilanus-Linthorst, M M; Bartels, C C; Obdeijn, A I; Oudkerk, M

    2000-03-01

    A positive family history increases the risk for breast cancer which oft en occurs at a much younger age than in the general population. We stud ied whether surveillance of these women resulted in the detection of bre ast cancer in an earlier stage than in symptomatic patients with a famil y history. Between January 1994 and April 1998, 294 women with 15-25% r isk (moderate), mean age:43.3 (22-75) years, were screened with a yearly physical examination and mammography from 5 years before the youngest ag e of onset in the family and 384 women with >25% risk (high) for breast cancer, mean age: 42.9 (20-74) years were screened with a physical examination every 6 months and yearly mammography. From September 1995 breast magnetic resonance imaging (MRI) was also carried out for 109 high risk women where mammography showed over 50% density. 26 breast cancers detected under surveillance were significantly more often found in an early T1N0 stage than the 24 breast cancers in patients with a family history referred in that period because of symptoms: 81 versus 46% (P=0.018). Patients under surveillance were also less frequently node-positive than the symptomatic group: 19 versus 42% (P=0.12). 20 patients with a family history referred by our national screening programme in that period had 21 breast cancers detected, 81% in stage T1N0 and 5% node-positive, which was comparable to the results in our national screening programme T1N0 66%, N+ 24% resulting in a 30% reduction in mortality. The incidence in women under surveillance was 10.1 per 1000 in the 'high' risk group and 13.3 per 1000 in the 'moderate' risk group. Expected incidence in an average risk population aged 40-50 years is 1.5, expected if the group consisted of only gene carriers 15 per 1000. 23% of the breast cancers in the surveillance group were detected at physical examination, but occult at mammography. 38% were detected at mammography and clinically occult. Breast MRI (in the subgroup) detected 3 occult

  16. Real life is different: a qualitative study of why women delay abortion until the second trimester in Vietnam.

    PubMed

    Gallo, Maria F; Nghia, Nguyen C

    2007-05-01

    Although legal and safe-induced abortion services are available on request in Vietnam, second-trimester abortion still occurs. Given the increased risks and higher costs associated with later-term abortions, we conducted a qualitative study to understand the determinants of delaying abortion until the second trimester. We used purposive sampling to conduct semi-structured face-to-face interviews with 60 women aged 14-47 receiving an abortion at 13-24 weeks of gestation in 5 health facilities in 3 provinces in Vietnam. We also interviewed 6 providers from the study facilities. Three broad categories for factors influencing delays in obtaining abortions emerged: most women failed to recognize their pregnancy during the first trimester; women described structural barriers to accessing services earlier; and some women either needed time to make a decision or only decided to abort after other events had transpired. A richer understanding of the factors that prevent women from obtaining an abortion during the first trimester could be useful for informing interventions that support women in receiving care earlier during their pregnancies.

  17. Complementary functions of the two brain hemispheres: comparisons with earlier conceptions and implications for individual and society.

    PubMed

    Zeier, H

    1989-07-01

    The concept of different functions for the left and right cerebral hemispheres coincides in an astonishing way with earlier philosophical and psychological work which divided the human mind into two complementary functions without having a neurophysiological explanation. Representative are the ideas of Fichte, Hegel and Jung. The latter postulated the two subsystems Ego and Self and associated the conscious functions of the Ego with the intellect, the capacity for rational thought, and the Self with the mind, which also includes the emotional feelings. For the harmonic development and self-realization of man the functions of both systems in complementary interaction are required. Therefore, the current overaccentuation of the intellect and of progress directed technical-scientific thinking should be corrected by making better use of the much neglected functions of the right hemisphere.

  18. An Assessment of Treatment Integrity in Behavioral Intervention Studies Conducted with Persons with Mental Retardation

    ERIC Educational Resources Information Center

    Wheeler, John J.; Mayton, Michael R.; Carter, Stacy L.; Chitiyo, Morgan; Menendez, Anthony L.; Huang, Ann

    2009-01-01

    The purpose of this study was to assess the degree to which behavioral intervention studies conducted with persons with mental retardation operationally defined the independent variables and evaluated and reported measures of treatment integrity. The study expands the previous work in this area reported by Gresham, Gansle, and Noell (1993) and…

  19. Theory of the Quantized Hall Conductance in Periodic Systems: a Topological Analysis.

    NASA Astrophysics Data System (ADS)

    Czerwinski, Michael Joseph

    The integral quantization of the Hall conductance in two-dimensional periodic systems is investigated from a topological point of view. Attention is focused on the contributions from the electronic sub-bands which arise from perturbed Landau levels. After reviewing the theoretical work leading to the identification of the Hall conductance as a topological quantum number, both a determination and interpretation of these quantized values for the sub-band conductances is made. It is shown that the Hall conductance of each sub-band can be regarded as the sum of two terms which will be referred to as classical and nonclassical. Although each of these contributions individually leads to a fractional conductance, the sum of these two contributions does indeed yield an integer. These integral conductances are found to be given by the solution of a simple Diophantine equation which depends on the periodic perturbation. A connection between the quantized value of the Hall conductance and the covering of real space by the zeroes of the sub-band wavefunctions allows for a determination of these conductances under more general potentials. A method is described for obtaining the conductance values from only those states bordering the Brillouin zone, and not the states in its interior. This method is demonstrated to give Hall conductances in agreement with those obtained from the Diophantine equation for the sinusoidal potential case explored earlier. Generalizing a simple gauge invariance argument from real space to k-space, a k-space 'vector potential' is introduced. This allows for a explicit identification of the Hall conductance with the phase winding number of the sub-band wavefunction around the Brillouin zone. The previously described division of the Hall conductance into classical and nonclassical contributions is in this way made more rigorous; based on periodicity considerations alone, these terms are identified as the winding numbers associated with (i) the basis

  20. Density of Electronic States in the Conduction Band of Ultrathin Films of Naphthalenedicarboxylic Anhydride and Naphthalenetetracarboxylic Dianhydride on the Surface of Oxidized Silicon

    NASA Astrophysics Data System (ADS)

    Komolov, A. S.; Lazneva, E. F.; Gerasimova, N. B.; Panina, Yu. A.; Baramygin, A. V.; Zashikhin, G. D.; Pshenichnyuk, S. A.

    2018-04-01

    The results of examination of the electronic structure of the conduction band of naphthalenedicarboxylic anhydride (NDCA) films in the process of their deposition on the surface of oxidized silicon are presented. These results were obtained using total current spectroscopy (TCS) in the energy range from 5 to 20 eV above the Fermi level. The energy position of the primary maxima of the density of unoccupied states (DOUS) of an NDCA film was determined based on the experimental TCS data and calculated data and compared with the position of the DOUS maxima of a naphthalenetetracarboxylic dianhydride (NTCDA) film. The theoretical analysis involved calculating the energies and the spatial distribution of orbitals of the molecules under study at the B3LYP/6-31G(d) DFT (density functional theory) level and correcting the obtained energies in accordance with the procedure that was proven effective in earlier studies of the conduction band of films of small conjugated organic molecules. It was found that the DOUS maxima of the NTCDA film in the studied energy interval from 5 to 20 eV above the Fermi level are shifted toward lower electron energies by 1-2 eV relative to the corresponding DOUS maxima of the NDCA film Subdivision of the Ufa Federal Research Centre of the.

  1. 43 CFR 404.19 - What requirements must be met before I can request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... request assistance to conduct a feasibility study? 404.19 Section 404.19 Public Lands: Interior... a feasibility study? All of the following requirements must be met before you can request assistance to conduct a feasibility study: (a) An appraisal investigation must be completed, with or without...

  2. Myocardial electrical conduction blockade time dominated by irradiance on photodynamic reaction: in vitro and in silico study

    NASA Astrophysics Data System (ADS)

    Ogawa, Emiyu; Arai, Tsunenori

    2018-02-01

    The time for electrical conduction blockade induced by a photodynamic reaction was studied on a myocardial cell wire in vitro and an in silico simulation model was constructed to understand the necessary time for electrical conduction blockade for the wire. Vulnerable state of the cells on a laser interaction would be an unstable and undesirable state since the cells might progress to completely damaged or repaired to change significantly therapeutic effect. So that in silico model, which can calculate the vulnerable cell state, is needed. Understanding an immediate electrical conduction blockade is needed for our proposed new methodology for tachyarrhythmia catheter ablation applying a photodynamic reaction. We studied the electrical conduction blockade occurrence on the electrical conduction wire made of cultured myocardial cells in a line shape and constructed in silico model based on this experimental data. The intracellular Ca2+ ion concentrations were obtained using Fluo-4 AM dye under a confocal laser microscope. A cross-correlation function was used for the electrical conduction blockade judgment. The photodynamic reaction was performed under the confocal microscopy with 3-120 mW/cm2 in irradiance by the diode laser with 663 nm in wavelength. We obtained that the time for the electrical conduction blockade decreased with the irradiance increasing. We constructed a simulation model composed of three states; living cells, vulnerable cells, and blocked cells, using the obtained experimental data and we found the rate constant by an optimization using a conjugate gradient method.

  3. Stratton Sagebrush Hydrology Study Area: An annotated bibliography of research conducted 1968-1990

    USGS Publications Warehouse

    Burgess, Leah M.; Schoenecker, Kathryn A.

    2004-01-01

    This annotated bibliography provides an overview of research projects conducted on the Stratton Sagebrush Hydrology Study Area (Stratton) since its designation as such in 1967. Sources include the Rocky Mountain Forest and Range Experiment Station records storage room, Laramie, Wyoming, the USGS and USFS online reference libraries, and scientific journal databases at the University of Wyoming and Colorado State University. This annotated bibliography summarizes publications from research conducted at Stratton during the prime of its tenure as a research lab from 1968 to 1990. In addition, an appendix is included that catalogues all data on file at the Rocky Mountain Forest and Range Experiment Station in Laramie, Wyoming. Each file folder was searched and its contents recorded here for the researcher seeking original data sets, charts, photographs and records.

  4. Electrical Conductivity of Ferritin Proteins by Conductive AFM

    NASA Technical Reports Server (NTRS)

    Xu, Degao; Watt, Gerald D.; Harb, John N.; Davis, Robert C.

    2005-01-01

    Electrical conductivity measurements were performed on single apoferritin and holoferritin molecules by conductive atomic force microscopy. Conductivity of self-assembled monolayer films of ferritin molecules on gold surfaces was also measured. Holoferritin was 5-25 times more conductive than apoferritin, indicating that for holoferritin most electron-transfer goes through the ferrihydrite core. With 1 V applied, the average electrical currents through single holoferritin and apoferritin molecules were 2.6 PA and 0.19 PA, respectively.

  5. The Association between Parent-Child Conflict and Adolescent Conduct Problems over Time: Results from a Longitudinal Adoption Study

    PubMed Central

    Klahr, Ashlea M.; McGue, Matt; Iacono, William G.; Burt, S. Alexandra

    2010-01-01

    A handful of prior adoption studies have confirmed that the cross-sectional relationship between child conduct problems and parent/child conflict is at least partially shared environmental in origin. However, as the direction of causation between parenting and delinquency remains unclear, this relationship could be better explained by the adolescent's propensity to elicit conflictive parenting, a phenomenon referred to as an evocative gene-environment correlation. The current study thus examined the prospective relationship between conduct problems and parent-child conflict in a sample of adoptive families. Participants included 672 adolescents in 405 adoptive families assessed at two time points roughly 4 years apart. Results indicated that parent-child conflict predicts the development of conduct problems, whereas conduct problems do not predict increases in parent-child conflict. Such findings suggest that evocative gene-environment correlations are highly unlikely as an explanation of prior shared environmental effects during adolescence. Moreover, because the adolescents in this study do not share genes with their adoptive parents, the association between conduct problems and parent-child conflict is indicative of shared environmental mediation in particular. Implications of our findings are discussed. PMID:21038930

  6. Mutual cancellation between tones presented by air conduction, by bone conduction and by non-osseous (soft tissue) bone conduction.

    PubMed

    Chordekar, Shai; Kriksunov, Leonid; Kishon-Rabin, Liat; Adelman, Cahtia; Sohmer, Haim

    2012-01-01

    Auditory sensation can be elicited not only by air conducted (AC) sound or bone conducted (BC) sound, but also by stimulation of soft tissue (STC) sites on the head and neck relatively distant from deeply underlying bone. Tone stimulation by paired combinations of AC with BC (mastoid) and/or with soft tissue conduction produce the same pitch sensation, mutual masking and beats. The present study was designed to determine whether they can also cancel each other. The study was conducted on ten normal hearing subjects. Tones at 2 kHz were presented in paired combinations by AC (insert earphone), by BC (bone vibrator) at the mastoid, and by the same bone vibrator to several STC sites; e.g. the neck, the sterno-cleido-mastoid muscle, the eye, and under the chin, shifting the phases between the pairs. Subjects reported changes in loudness and cancellation. The phase for cancellation differed across subjects. Neck muscle manipulations (changes in head position) led to alterations in the phase at which cancellation was reported. Cancellation was also achieved between pairs of tones to two STC sites. The differing phases for cancellation across subjects and the change in phase accompanying different head positions may be due to the different acoustic impedances of the several tissues in the head and neck. A major component of auditory stimulation by STC may not induce actual skull bone vibrations and may not involve bulk fluid volume displacements. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Conducting interactive experiments online.

    PubMed

    Arechar, Antonio A; Gächter, Simon; Molleman, Lucas

    2018-01-01

    Online labor markets provide new opportunities for behavioral research, but conducting economic experiments online raises important methodological challenges. This particularly holds for interactive designs. In this paper, we provide a methodological discussion of the similarities and differences between interactive experiments conducted in the laboratory and online. To this end, we conduct a repeated public goods experiment with and without punishment using samples from the laboratory and the online platform Amazon Mechanical Turk. We chose to replicate this experiment because it is long and logistically complex. It therefore provides a good case study for discussing the methodological and practical challenges of online interactive experimentation. We find that basic behavioral patterns of cooperation and punishment in the laboratory are replicable online. The most important challenge of online interactive experiments is participant dropout. We discuss measures for reducing dropout and show that, for our case study, dropouts are exogenous to the experiment. We conclude that data quality for interactive experiments via the Internet is adequate and reliable, making online interactive experimentation a potentially valuable complement to laboratory studies.

  8. Experimental and numerical study on thermal conductivity of partially saturated unconsolidated sands

    NASA Astrophysics Data System (ADS)

    Lee, Youngmin; Keehm, Youngseuk; Kim, Seong-Kyun; Shin, Sang Ho

    2016-04-01

    A class of problems in heat flow applications requires an understanding of how water saturation affects thermal conductivity in the shallow subsurface. We conducted a series of experiments using a sand box to evaluate thermal conductivity (TC) of partially saturated unconsolidated sands under varying water saturation (Sw). We first saturated sands fully with water and varied water saturation by drainage through the bottom of the sand box. Five water-content sensors were integrated vertically into the sand box to monitor water saturation changes and a needle probe was embedded to measure thermal conductivity of partially saturated sands. The experimental result showed that thermal conductivity decreases from 2.5 W/mK for fully saturated sands to 0.7 W/mK when water saturation is 5%. We found that the decreasing trend is quite non-linear: highly sensitive at very high and low water saturations. However, the boundary effects on the top and the bottom of the sand box seemed to be responsible for this high nonlinearity. We also found that the determination of water saturation is quite important: the saturation by averaging values from all five sensors and that from the sensor at the center position, showed quite different trends in the TC-Sw domain. In parallel, we conducted a pore-scale numerical modeling, which consists of the steady-state two-phase Lattice-Boltzmann simulator and FEM thermal conduction simulator on digital pore geometry of sand aggregation. The simulation results showed a monotonous decreasing trend, and are reasonably well matched with experimental data when using average water saturations. We concluded that thermal conductivity would decrease smoothly as water saturation decreases if we can exclude boundary effects. However, in dynamic conditions, i.e. imbibition or drainage, the thermal conductivity might show hysteresis, which can be investigated with pore-scale numerical modeling with unsteady-state two-phase flow simulators in our future work.

  9. A systematic review comparing antiretroviral adherence descriptive and intervention studies conducted in the USA.

    PubMed

    Sandelowski, Margarete; Voils, Corrine I; Chang, Yunkyung; Lee, Eun-Jeong

    2009-08-01

    We examined the extent to which studies aimed at testing interventions to improve antiretroviral adherence have targeted the facilitators of and barriers known to affect adherence. Of the 88 reports reviewed, 41 were reports of descriptive studies conducted with US HIV-positive women and 47 were reports of intervention studies conducted with US HIV-positive persons. We extracted from the descriptive studies all findings addressing any factor linked to antiretroviral adherence and from the intervention studies, information on the nature of the intervention, the adherence problem targeted, the persons targeted for the intervention, and the intervention outcomes desired. We discerned congruence between the prominence of substance abuse as a factor identified in the descriptive studies as a barrier to adherence and its prominence as the problem most addressed in those reports of intervention studies that specified the problems targeted for intervention. We also discerned congruence between the prominence of family and provider support as factors identified in the descriptive studies as facilitators of adherence and the presence of social support as an intervention component and outcome variable. Less discernible in the reports of intervention studies was specific attention to other factors prominent in the descriptive studies, which may be due to the complex nature of the problem, individualistic and rationalist slant of interventions, or simply the ways interventions were presented. Our review raises issues about niche standardization and intervention tailoring, targeting, and fidelity.

  10. Using framework-based synthesis for conducting reviews of qualitative studies.

    PubMed

    Dixon-Woods, Mary

    2011-04-14

    Framework analysis is a technique used for data analysis in primary qualitative research. Recent years have seen its being adapted to conduct syntheses of qualitative studies. Framework-based synthesis shows considerable promise in addressing applied policy questions. An innovation in the approach, known as 'best fit' framework synthesis, has been published in BMC Medical Research Methodology this month. It involves reviewers in choosing a conceptual model likely to be suitable for the question of the review, and using it as the basis of their initial coding framework. This framework is then modified in response to the evidence reported in the studies in the reviews, so that the final product is a revised framework that may include both modified factors and new factors that were not anticipated in the original model. 'Best fit' framework-based synthesis may be especially suitable in addressing urgent policy questions where the need for a more fully developed synthesis is balanced by the need for a quick answer. Please see related article: http://www.biomedcentral.com/1471-2288/11/29.

  11. 2011 Annual Survey of Journalism and Mass Communication Enrollments: Enrollments Decline, Reversing the Increase of a Year Earlier, and Suggesting Slow Growth for Future

    ERIC Educational Resources Information Center

    Becker, Lee B.; Vlad, Tudor; Kalpen, Konrad

    2012-01-01

    Enrollments in journalism and mass communication programs declined in the autumn of 2011, compared to a year earlier. Enrollments were down slightly at the senior and junior levels and substantially at the freshman level. Enrollment increased at the sophomore level. The majority of administrators say they have made curricular changes in the past…

  12. Statistical issues in the design, conduct and analysis of two large safety studies.

    PubMed

    Gaffney, Michael

    2016-10-01

    The emergence, post approval, of serious medical events, which may be associated with the use of a particular drug or class of drugs, is an important public health and regulatory issue. The best method to address this issue is through a large, rigorously designed safety study. Therefore, it is important to elucidate the statistical issues involved in these large safety studies. Two such studies are PRECISION and EAGLES. PRECISION is the primary focus of this article. PRECISION is a non-inferiority design with a clinically relevant non-inferiority margin. Statistical issues in the design, conduct and analysis of PRECISION are discussed. Quantitative and clinical aspects of the selection of the composite primary endpoint, the determination and role of the non-inferiority margin in a large safety study and the intent-to-treat and modified intent-to-treat analyses in a non-inferiority safety study are shown. Protocol changes that were necessary during the conduct of PRECISION are discussed from a statistical perspective. Issues regarding the complex analysis and interpretation of the results of PRECISION are outlined. EAGLES is presented as a large, rigorously designed safety study when a non-inferiority margin was not able to be determined by a strong clinical/scientific method. In general, when a non-inferiority margin is not able to be determined, the width of the 95% confidence interval is a way to size the study and to assess the cost-benefit of relative trial size. A non-inferiority margin, when able to be determined by a strong scientific method, should be included in a large safety study. Although these studies could not be called "pragmatic," they are examples of best real-world designs to address safety and regulatory concerns. © The Author(s) 2016.

  13. Conductive properties of methanogenic biofilms.

    PubMed

    Li, Cheng; Lesnik, Keaton Larson; Liu, Hong

    2018-02-01

    Extracellular electron transfer between syntrophic partners needs to be efficiently maintained in methanogenic environments. Direct extracellular electron transfer via electrical current is an alternative to indirect hydrogen transfer but requires construction of conductive extracellular structures. Conductive mechanisms and relationship between conductivity and the community composition in mixed-species methanogenic biofilms are not well understood. The present study investigated conductive behaviors of methanogenic biofilms and examined the correlation between biofilm conductivity and community composition between different anaerobic biofilms enriched from the same inoculum. Highest conductivity observed in methanogenic biofilms was 71.8±4.0μS/cm. Peak-manner response of conductivity upon changes over a range of electrochemical potentials suggests that electron transfer in methanogenic biofilms occurs through redox driven super-exchange. The strong correlation observed between biofilm conductivity and Geobacter spp. in the metabolically diverse anaerobic communities suggests that the efficiency of DEET may provide pressure for microbial communities to select for species that can produce electrical conduits. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Conduct Disorder Symptoms and Subsequent Pregnancy, Child-Birth and Abortion: A Population-Based Longitudinal Study of Adolescents

    ERIC Educational Resources Information Center

    Pedersen, Willy; Mastekaasa, Arne

    2011-01-01

    Research on teenage pregnancy and abortion has primarily focused on socio-economic disadvantage. However, a few studies suggest that risk of unwanted pregnancy is related to conduct disorder symptoms. We examined the relationship between level of conduct disorder symptoms at age 15 and subsequent pregnancy, child-birth and abortion. A…

  15. Earlier occurrence and increased explanatory power of climate for the first incidence of potato late blight caused by Phytophthora infestans in Fennoscandia.

    PubMed

    Lehsten, Veiko; Wiik, Lars; Hannukkala, Asko; Andreasson, Erik; Chen, Deliang; Ou, Tinghai; Liljeroth, Erland; Lankinen, Åsa; Grenville-Briggs, Laura

    2017-01-01

    Late blight (caused by Phytophthora infestans) is a devastating potato disease that has been found to occur earlier in the season over the last decades in Fennoscandia. Up until now the reasons for this change have not been investigated. Possible explanations for this change are climate alterations, changes in potato production or changes in pathogen biology, such as increased fitness or changes in gene flow within P. infestans populations. The first incidence of late blight is of high economic importance since fungicidal applications should be typically applied two weeks before the first signs of late blight and are repeated on average once a week. We use field observations of first incidence of late blight in experimental potato fields from five sites in Sweden and Finland covering a total of 30 years and investigate whether the earlier incidence of late blight can be related to the climate. We linked the field data to meteorological data and found that the previous assumption, used in common late blight models, that the disease only develops at relative humidity levels above 90% had to be rejected. Rather than the typically assumed threshold relationship between late blight disease development and relative humidity we found a linear relationship. Our model furthermore showed two distinct responses of late blight to climate. At the beginning of the observation time (in Sweden until the early 90s and in Finland until the 2000s) the link between climate and first incidence was very weak. However, for the remainder of the time period the link was highly significant, indicating a change in the biological properties of the pathogen which could for example be a change in the dominating reproduction mode or a physiological change in the response of the pathogen to climate. The study shows that models used in decision support systems need to be checked and re-parametrized regularly to be able to capture changes in pathogen biology. While this study was performed with

  16. Summary report on UO 2 thermal conductivity model refinement and assessment studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Xiang-Yang; Cooper, Michael William Donald; Mcclellan, Kenneth James

    Uranium dioxide (UO 2) is the most commonly used fuel in light water nuclear reactors and thermal conductivity controls the removal of heat produced by fission, therefore, governing fuel temperature during normal and accident conditions. The use of fuel performance codes by the industry to predict operational behavior is widespread. A primary source of uncertainty in these codes is thermal conductivity, and optimized fuel utilization may be possible if existing empirical models were replaced with models that incorporate explicit thermal conductivity degradation mechanisms during fuel burn-up. This approach is able to represent the degradation of thermal conductivity due to eachmore » individual defect type, rather than the overall burn-up measure typically used which is not an accurate representation of the chemical or microstructure state of the fuel that actually governs thermal conductivity and other properties. To generate a mechanistic thermal conductivity model, molecular dynamics (MD) simulations of UO 2 thermal conductivity including representative uranium and oxygen defects and fission products are carried out. These calculations employ a standard Buckingham type interatomic potential and a potential that combines the many-body embedded atom method potential with Morse-Buckingham pair potentials. Potential parameters for UO 2+x and ZrO 2 are developed for the latter potential. Physical insights from the resonant phonon-spin scattering mechanism due to spins on the magnetic uranium ions have been introduced into the treatment of the MD results, with the corresponding relaxation time derived from existing experimental data. High defect scattering is predicted for Xe atoms compared to that of La and Zr ions. Uranium defects reduce the thermal conductivity more than oxygen defects. For each defect and fission product, scattering parameters are derived for application in both a Callaway model and the corresponding high-temperature model typically used in fuel

  17. Indicators: Conductivity

    EPA Pesticide Factsheets

    Conductivity is a measure of the ability of water to pass an electrical current. Because dissolved salts and other inorganic chemicals conduct electrical current, conductivity increases as salinity increases.

  18. Theoretical and Experimental Studies of Functionalized Carbon Nanotubes for Improved Thermal Conductivity

    NASA Astrophysics Data System (ADS)

    Kerr, Alexander; Burt, Timothy; Mullen, Kieran; Glatzhofer, Daniel; Houck, Matthew; Huang, Paul

    The use of carbon nanotubes (CNTs) to improve the thermal conductivity of composite materials is thwarted by their large thermal boundary resistance. We study how to overcome this Kapitza resistance by functionalizing CNTs with mixed molecular chains. Certain configurations of chains improve the transmission of thermal vibrations through our systems by decreasing phonon mismatch between the CNTs and their surrounding matrix. Through the calculation of vibrational normal modes and Green's functions, we develop a variety of computational metrics to compare the thermal conductivity (κ) of our systems. We show how different configurations of attached chains affect the samples' κ values by varying chain identity, chain length, number of chains, and heat driver behavior. We vary the parameters to maximize κ. To validate and optimize these metrics, we perform molecular dynamics simulations for comparison. We also present experimental results of composites enhanced with CNTs and make comparisons to the theory. We observe that some composites are thermally improved with the inclusion of CNTs, while others are scarcely changed, in agreement with theoretical models. This work was supported by NSF Grant DMR-1310407.

  19. Current at domain walls, roughly speaking: nanoscales studies of disorder roughening and conduction

    NASA Astrophysics Data System (ADS)

    Paruch, Patrycja

    2013-03-01

    Domain walls in (multi)ferroic materials are the thin elastic interfaces separating regions with different orientations of magnetisation, electric polarisation, or spontaneous strain. Understanding their behaviour, and controlling domain size and stability, is key for their integration into applications, while fundamentally, domain walls provide an excellent model system in which the rich physics of disordered elastic interfaces can be accesses. In addition, domain walls can present novel properties, quite different from those of their parent materials, making them potentially useful as active components in future nano-devices. Here, we present our atomic force microscopy studies of ferroelectric domain walls in epitaxial Pb(Zr0.2Ti0.8)O3 and BiFeO3 thin films, in which we use piezorespose force microscopy to show unusual domain wall roughening behaviour, with very localised disorder regions in the sample leading to a complex, multi-affine scaling of the domain wall shape. We also show the effects of temperature, environmental conditions, and defects on switching dynamics and domain wall roughness. We combine these observations with parallel conductive-tip atomic force microscopy current measurements, which also show highly localised variations in conduction, and highlight the key role played by oxygen vacancies in the observed domain wall conduction.

  20. 21 CFR 320.25 - Guidelines for the conduct of an in vivo bioavailability study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... conduct of an in vivo bioavailability study. (a) Guiding principles. (1) The basic principle in an in vivo... not been approved for marketing can be used to measure the following pharmacokinetic data: (i) The bioavailability of the formulation proposed for marketing; and (ii) The essential pharmacokinetic characteristics...

  1. Electrical conductivity studies on Ammonium bromide incorporated with Zwitterionic polymer blend electrolyte for battery application

    NASA Astrophysics Data System (ADS)

    Parameswaran, V.; Nallamuthu, N.; Devendran, P.; Nagarajan, E. R.; Manikandan, A.

    2017-06-01

    Solid polymer blend electrolytes are widely studied due to their extensive applications particularly in electrochemical devices. Blending polymer makes the thermal stability, higher mechanical strength and inorganic salt provide ionic charge carrier to enhance the conductivity. In these studies, 50% polyvinyl alcohol (PVA), 50% poly (N-vinyl pyrrolidone) (PVP) and 2.5% L-Asparagine mixed with different ratio of the Ammonium bromide (NH4Br), have been synthesized using solution casting technique. The prepared PVA/PVP/L-Asparagine/doped-NH4Br polymer blend electrolyte films have been characterized by various analytical methods such as FT-IR, XRD, impedance spectroscopy, TG-DSC and scanning electron microscopy. FT-IR, XRD and TG/DSC analysis revealed the structural and thermal behavior of the complex formation between PVA/PVP/L-Asparagine/doped-NH4Br. The ionic conductivity and the dielectric properties of PVA/PVP/L-Asparagine/doped-NH4Br polymer blend electrolyte films were examined using impedance analysis. The highest ionic conductivity was found to be 2.34×10-4 S cm-1 for the m.wt. composition of 50%PVA:50%PVP:2.5%L-Asparagine:doped 0.15 g NH4Br at ambient temperature. Solid state proton battery is fabricated and the observed open circuit voltage is 1.1 V and its performance has been studied.

  2. Compensated Arrhenius formalism applied to a conductivity study in poly(propylene glycol) diacrylate monomers.

    PubMed

    Dubois, F; Derouiche, Y; Leblond, J M; Maschke, U; Douali, R

    2015-09-01

    The temperature dependence of the ionic conductivity is studied in a series of poly(propylene glycol) diacrylate monomers. The experimental data are analyzed by means of the approach recently proposed by Petrowsky et al. [J. Phys. Chem. B. 113, 5996 (2009)10.1021/jp810095g]. This so-called compensated Arrhenius formalism (CAF) approach takes into account the influence of the dielectric permittivity on the exponential prefactor in the classical Arrhenius equation. The experimental data presented in this paper show a good agreement with the CAF; this means that the exponential prefactor is principally dielectric permittivity dependent. The compensated data revealed two conduction processes with different activation energies; they correspond to low and high temperature ranges, respectively.

  3. Compensated Arrhenius formalism applied to a conductivity study in poly(propylene glycol) diacrylate monomers

    NASA Astrophysics Data System (ADS)

    Dubois, F.; Derouiche, Y.; Leblond, J. M.; Maschke, U.; Douali, R.

    2015-09-01

    The temperature dependence of the ionic conductivity is studied in a series of poly(propylene glycol) diacrylate monomers. The experimental data are analyzed by means of the approach recently proposed by Petrowsky et al. [J. Phys. Chem. B. 113, 5996 (2009), 10.1021/jp810095g]. This so-called compensated Arrhenius formalism (CAF) approach takes into account the influence of the dielectric permittivity on the exponential prefactor in the classical Arrhenius equation. The experimental data presented in this paper show a good agreement with the CAF; this means that the exponential prefactor is principally dielectric permittivity dependent. The compensated data revealed two conduction processes with different activation energies; they correspond to low and high temperature ranges, respectively.

  4. Tg.rasH2 Mice and not CByB6F1 Mice Should Be Used for 28-Day Dose Range Finding Studies Prior to 26-Week Tg.rasH2 Carcinogenicity Studies.

    PubMed

    Paranjpe, Madhav G; Belich, Jessica; Vidmar, Tom J; Elbekai, Reem H; McKeon, Marie; Brown, Caren

    Our recent retrospective analysis of data, collected from 29 Tg.rasH2 mouse carcinogenicity studies, determined how successful the strategy of choosing the high dose for the 26-week studies was based on the estimated maximum tolerated dose (EMTD) derived from earlier 28-day dose range finding (DRF) studies conducted in CByB6F1 mice. Our analysis demonstrated that the high doses applied at EMTD in the 26-week Tg.rasH2 studies failed to detect carcinogenic effects. To investigate why the dose selection process failed in the 26-week carcinogenicity studies, the initial body weights, terminal body weights, body weight gains, food consumption, and mortality from the first 4 weeks of 26-week studies with Tg.rasH2 mice were compared with 28-day DRF studies conducted with CByB6F1 mice. Both the 26-week and the earlier respective 28-day studies were conducted with the exact same vehicle, test article, and similar dose levels. The analysis of our results further emphasizes that the EMTD and subsequent lower doses, determined on the basis of the 28-day studies in CByB6F1 mice, may not be an accurate strategy for selecting appropriate dose levels for the 26-week carcinogenicity studies in Tg.rasH2 mice. Based on the analysis presented in this article, we propose that the Tg.rasH2 mice and not the CByB6F1 mice should be used in future DRF studies. The Tg.rasH2 mice demonstrate more toxicity than the CByB6F1 mice, possibly because of their smaller size compared to CByB6F1 mice. Also, the Tg.rasH2 males appear to be more sensitive than the female Tg.rasH2 mice.

  5. The Chinese Visible Human (CVH) datasets incorporate technical and imaging advances on earlier digital humans

    PubMed Central

    Zhang, Shao-Xiang; Heng, Pheng-Ann; Liu, Zheng-Jin; Tan, Li-Wen; Qiu, Ming-Guo; Li, Qi-Yu; Liao, Rong-Xia; Li, Kai; Cui, Gao-Yu; Guo, Yan-Li; Yang, Xiao-Ping; Liu, Guang-Jiu; Shan, Jing-Lu; Liu, Ji-Jun; Zhang, Wei-Guo; Chen, Xian-Hong; Chen, Jin-Hua; Wang, Jian; Chen, Wei; Lu, Ming; You, Jian; Pang, Xue-Li; Xiao, Hong; Xie, Yong-Ming; Cheng, Jack Chun-Yiu

    2004-01-01

    We report the availability of a digitized Chinese male and a digitzed Chinese female typical of the population and with no obvious abnormalities. The embalming and milling procedures incorporate three technical improvements over earlier digitized cadavers. Vascular perfusion with coloured gelatin was performed to facilitate blood vessel identification. Embalmed cadavers were embedded in gelatin and cryosectioned whole so as to avoid section loss resulting from cutting the body into smaller pieces. Milling performed at −25 °C prevented small structures (e.g. teeth, concha nasalis and articular cartilage) from falling off from the milling surface. The male image set (.tiff images each of 36 Mb) has a section resolution of 3072 × 2048 pixels (∼170 μm, the accompanying magnetic resonance imaging and computer tomography data have a resolution of 512 × 512, i.e. ∼440 μm). The Chinese Visible Human male and female datasets are available at http://www.chinesevisiblehuman.com. (The male is 90.65 Gb and female 131.04 Gb). MPEG videos of direct records of real-time volume rendering are at: http://www.cse.cuhk.edu.hk/~crc PMID:15032906

  6. Five hydrologic studies conducted by or in cooperation with the Center for Forested Wetlands Research

    Treesearch

    Devendra M. Amatya; Carl C. Trettin; R. Wayne Skaggs; T.J. Callahan; Ge Sun; J.E. Nettles; J.E. Parsons; M. Miwa

    2005-01-01

    The U.S. Department of Agriculture Forest Service Center for Forested Wetlands Research has conducted or cooperated in studies designed to improve understanding of fundamental hydrologic and biogeochemical processes that link aquatic and terrestrial ecosystems. Five of these studies are discussed here. The first is based on observations made on long-term experimental...

  7. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How will a feasibility study be conducted under this program? 404.47 Section 404.47 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Feasibility...

  8. Skin conductance fear conditioning impairments and aggression: a longitudinal study.

    PubMed

    Gao, Yu; Tuvblad, Catherine; Schell, Anne; Baker, Laura; Raine, Adrian

    2015-02-01

    Autonomic fear conditioning deficits have been linked to child aggression and adult criminal behavior. However, it is unknown if fear conditioning deficits are specific to certain subtypes of aggression, and longitudinal research is rare. In the current study, reactive and proactive aggression were assessed in a sample of males and females when aged 10, 12, 15, and 18 years old. Skin conductance fear conditioning data were collected when they were 18 years old. Individuals who were persistently high on proactive aggression measures had significantly poorer conditioned responses at 18 years old when compared to others. This association was not found for reactive aggression. Consistent with prior literature, findings suggest that persistent antisocial individuals have unique neurobiological characteristics and that poor autonomic fear conditioning is associated with the presence of increased instrumental aggressive behavior. © 2014 Society for Psychophysiological Research.

  9. Community Violence Exposure and Conduct Problems in Children and Adolescents with Conduct Disorder and Healthy Controls

    PubMed Central

    Kersten, Linda; Vriends, Noortje; Steppan, Martin; Raschle, Nora M.; Praetzlich, Martin; Oldenhof, Helena; Vermeiren, Robert; Jansen, Lucres; Ackermann, Katharina; Bernhard, Anka; Martinelli, Anne; Gonzalez-Madruga, Karen; Puzzo, Ignazio; Wells, Amy; Rogers, Jack C.; Clanton, Roberta; Baker, Rosalind H.; Grisley, Liam; Baumann, Sarah; Gundlach, Malou; Kohls, Gregor; Gonzalez-Torres, Miguel A.; Sesma-Pardo, Eva; Dochnal, Roberta; Lazaratou, Helen; Kalogerakis, Zacharias; Bigorra Gualba, Aitana; Smaragdi, Areti; Siklósi, Réka; Dikeos, Dimitris; Hervás, Amaia; Fernández-Rivas, Aranzazu; De Brito, Stephane A.; Konrad, Kerstin; Herpertz-Dahlmann, Beate; Fairchild, Graeme; Freitag, Christine M.; Popma, Arne; Kieser, Meinhard; Stadler, Christina

    2017-01-01

    Exposure to community violence through witnessing or being directly victimized has been associated with conduct problems in a range of studies. However, the relationship between community violence exposure (CVE) and conduct problems has never been studied separately in healthy individuals and individuals with conduct disorder (CD). Therefore, it is not clear whether the association between CVE and conduct problems is due to confounding factors, because those with high conduct problems also tend to live in more violent neighborhoods, i.e., an ecological fallacy. Hence, the aim of the present study was: (1) to investigate whether the association between recent CVE and current conduct problems holds true for healthy controls as well as adolescents with a diagnosis of CD; (2) to examine whether the association is stable in both groups when including effects of aggression subtypes (proactive/reactive aggression), age, gender, site and socioeconomic status (SES); and (3) to test whether proactive or reactive aggression mediate the link between CVE and conduct problems. Data from 1178 children and adolescents (62% female; 44% CD) aged between 9 years and 18 years from seven European countries were analyzed. Conduct problems were assessed using the Kiddie-Schedule of Affective Disorders and Schizophrenia diagnostic interview. Information about CVE and aggression subtypes was obtained using self-report questionnaires (Social and Health Assessment and Reactive-Proactive aggression Questionnaire (RPQ), respectively). The association between witnessing community violence and conduct problems was significant in both groups (adolescents with CD and healthy controls). The association was also stable after examining the mediating effects of aggression subtypes while including moderating effects of age, gender and SES and controlling for effects of site in both groups. There were no clear differences between the groups in the strength of the association between witnessing violence

  10. Community Violence Exposure and Conduct Problems in Children and Adolescents with Conduct Disorder and Healthy Controls.

    PubMed

    Kersten, Linda; Vriends, Noortje; Steppan, Martin; Raschle, Nora M; Praetzlich, Martin; Oldenhof, Helena; Vermeiren, Robert; Jansen, Lucres; Ackermann, Katharina; Bernhard, Anka; Martinelli, Anne; Gonzalez-Madruga, Karen; Puzzo, Ignazio; Wells, Amy; Rogers, Jack C; Clanton, Roberta; Baker, Rosalind H; Grisley, Liam; Baumann, Sarah; Gundlach, Malou; Kohls, Gregor; Gonzalez-Torres, Miguel A; Sesma-Pardo, Eva; Dochnal, Roberta; Lazaratou, Helen; Kalogerakis, Zacharias; Bigorra Gualba, Aitana; Smaragdi, Areti; Siklósi, Réka; Dikeos, Dimitris; Hervás, Amaia; Fernández-Rivas, Aranzazu; De Brito, Stephane A; Konrad, Kerstin; Herpertz-Dahlmann, Beate; Fairchild, Graeme; Freitag, Christine M; Popma, Arne; Kieser, Meinhard; Stadler, Christina

    2017-01-01

    Exposure to community violence through witnessing or being directly victimized has been associated with conduct problems in a range of studies. However, the relationship between community violence exposure (CVE) and conduct problems has never been studied separately in healthy individuals and individuals with conduct disorder (CD). Therefore, it is not clear whether the association between CVE and conduct problems is due to confounding factors, because those with high conduct problems also tend to live in more violent neighborhoods, i.e., an ecological fallacy. Hence, the aim of the present study was: (1) to investigate whether the association between recent CVE and current conduct problems holds true for healthy controls as well as adolescents with a diagnosis of CD; (2) to examine whether the association is stable in both groups when including effects of aggression subtypes (proactive/reactive aggression), age, gender, site and socioeconomic status (SES); and (3) to test whether proactive or reactive aggression mediate the link between CVE and conduct problems. Data from 1178 children and adolescents (62% female; 44% CD) aged between 9 years and 18 years from seven European countries were analyzed. Conduct problems were assessed using the Kiddie-Schedule of Affective Disorders and Schizophrenia diagnostic interview. Information about CVE and aggression subtypes was obtained using self-report questionnaires (Social and Health Assessment and Reactive-Proactive aggression Questionnaire (RPQ), respectively). The association between witnessing community violence and conduct problems was significant in both groups (adolescents with CD and healthy controls). The association was also stable after examining the mediating effects of aggression subtypes while including moderating effects of age, gender and SES and controlling for effects of site in both groups. There were no clear differences between the groups in the strength of the association between witnessing violence

  11. Density functional theory and conductivity studies of boron-based anion receptors

    DOE PAGES

    Leung, Kevin; Chaudhari, Mangesh I.; Rempe, Susan B.; ...

    2015-07-10

    Anion receptors that bind strongly to fluoride anions in organic solvents can help dissolve the lithium fluoride discharge products of primary carbon monofluoride (CFx) batteries, thereby preventing the clogging of cathode surfaces and improving ion conductivity. The receptors are also potentially beneficial to rechargeable lithium ion and lithium air batteries. We apply Density Functional Theory (DFT) to show that an oxalate-based pentafluorophenyl-boron anion receptor binds as strongly, or more strongly, to fluoride anions than many phenyl-boron anion receptors proposed in the literature. Experimental data shows marked improvement in electrolyte conductivity when this oxalate anion receptor is present. The receptor ismore » sufficiently electrophilic that organic solvent molecules compete with F – for boron-site binding, and specific solvent effects must be considered when predicting its F – affinity. To further illustrate the last point, we also perform computational studies on a geometrically constrained boron ester that exhibits much stronger gas-phase affinity for both F – and organic solvent molecules. After accounting for specific solvent effects, however, its net F – affinity is about the same as the simple oxalate-based anion receptor. Lastly, we propose that LiF dissolution in cyclic carbonate organic solvents, in the absence of anion receptors, is due mostly to the formation of ionic aggregates, not isolated F – ions.« less

  12. Characterizing Measurement Error in Test Scores across Studies: A Tutorial on Conducting "Reliability Generalization" Analyses.

    ERIC Educational Resources Information Center

    Henson, Robin K.; Thompson, Bruce

    Given the potential value of reliability generalization (RG) studies in the development of cumulative psychometric knowledge, the purpose of this paper is to provide a tutorial on how to conduct such studies and to serve as a guide for researchers wishing to use this methodology. After some brief comments on classical test theory, the paper…

  13. Leaf anatomy mediates coordination of leaf hydraulic conductance and mesophyll conductance to CO2 in Oryza.

    PubMed

    Xiong, Dongliang; Flexas, Jaume; Yu, Tingting; Peng, Shaobing; Huang, Jianliang

    2017-01-01

    Leaf hydraulic conductance (K leaf ) and mesophyll conductance (g m ) both represent major constraints to photosynthetic rate (A), and previous studies have suggested that K leaf and g m is correlated in leaves. However, there is scarce empirical information about their correlation. In this study, K leaf , leaf hydraulic conductance inside xylem (K x ), leaf hydraulic conductance outside xylem (K ox ), A, stomatal conductance (g s ), g m , and anatomical and structural leaf traits in 11 Oryza genotypes were investigated to elucidate the correlation of H 2 O and CO 2 diffusion inside leaves. All of the leaf functional and anatomical traits varied significantly among genotypes. K leaf was not correlated with the maximum theoretical stomatal conductance calculated from stomatal dimensions (g smax ), and neither g s nor g smax were correlated with K x . Moreover, K ox was linearly correlated with g m and both were closely related to mesophyll structural traits. These results suggest that K leaf and g m are related to leaf anatomical and structural features, which may explain the mechanism for correlation between g m and K leaf . © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  14. Handbook of Instructions for Conducting Follow-Up Studies of High School Graduates. Book I.

    ERIC Educational Resources Information Center

    Donaldson, Evelyn T. Comp.; And Others

    This handbook is designed to enable high schools to conduct follow-up studies on their graduates for 5 years after graduation. The information gathered should give schools pertinent data about: (1) post high school activities of graduates; (2) reactions of graduates to counseling and guidance opportunities; (3) reactions of graduates to…

  15. Computational analysis of electrical conduction in hybrid nanomaterials with embedded non-penetrating conductive particles

    NASA Astrophysics Data System (ADS)

    Cai, Jizhe; Naraghi, Mohammad

    2016-08-01

    In this work, a comprehensive multi-resolution two-dimensional (2D) resistor network model is proposed to analyze the electrical conductivity of hybrid nanomaterials made of insulating matrix with conductive particles such as CNT reinforced nanocomposites and thick film resistors. Unlike existing approaches, our model takes into account the impenetrability of the particles and their random placement within the matrix. Moreover, our model presents a detailed description of intra-particle conductivity via finite element analysis, which to the authors’ best knowledge has not been addressed before. The inter-particle conductivity is assumed to be primarily due to electron tunneling. The model is then used to predict the electrical conductivity of electrospun carbon nanofibers as a function of microstructural parameters such as turbostratic domain alignment and aspect ratio. To simulate the microstructure of single CNF, randomly positioned nucleation sites were seeded and grown as turbostratic particles with anisotropic growth rates. Particle growth was in steps and growth of each particle in each direction was stopped upon contact with other particles. The study points to the significant contribution of both intra-particle and inter-particle conductivity to the overall conductivity of hybrid composites. Influence of particle alignment and anisotropic growth rate ratio on electrical conductivity is also discussed. The results show that partial alignment in contrast to complete alignment can result in maximum electrical conductivity of whole CNF. High degrees of alignment can adversely affect conductivity by lowering the probability of the formation of a conductive path. The results demonstrate approaches to enhance electrical conductivity of hybrid materials through controlling their microstructure which is applicable not only to carbon nanofibers, but also many other types of hybrid composites such as thick film resistors.

  16. Method and apparatus for casting conductive and semi-conductive materials

    DOEpatents

    Ciszek, T.F.

    1984-08-13

    A method and apparatus is disclosed for casting conductive and semi-conductive materials. The apparatus includes a plurality of conductive members arranged to define a container-like area having a desired cross-sectional shape. A portion or all of the conductive or semi-conductive material which is to be cast is introduced into the container-like area. A means is provided for inducing the flow of an electrical current in each of the conductive members, which currents act collectively to induce a current flow in the material. The induced current flow through the conductive members is in a direction substantially opposite to the induced current flow in the material so that the material is repelled from the conductive members during the casting process.

  17. Study on Unit Cell Models and the Effective Thermal Conductivities of Silica Aerogel.

    PubMed

    Liu, He; Li, Zeng-Yao; Zhao, Xin-Peng; Tao, Wen-Quan

    2015-04-01

    In this paper, two modified unit cell models, truncated octahedron and cubic array of intersecting square rods with 45-degree rotation, are developed in consideration of the tortuous path of heat conduction in solid skeleton of silica aerogel. The heat conduction is analyzed for each model and the expressions of effective thermal conductivity of the modified unit cell models are derived. Considering the random microstructure of silica aerogel, the probability model is presented. We also discuss the effect of the thermal conductivity of aerogel backbone. The effective thermal conductivities calculated by the proposed probability model are in good agreement with available experimental data when the density of the aerogel is 110 kg/m3.

  18. Studying the Transient Thermal Contact Conductance Between the Exhaust Valve and Its Seat Using the Inverse Method

    NASA Astrophysics Data System (ADS)

    Nezhad, Mohsen Motahari; Shojaeefard, Mohammad Hassan; Shahraki, Saeid

    2016-02-01

    In this study, the experiments aimed at analyzing thermally the exhaust valve in an air-cooled internal combustion engine and estimating the thermal contact conductance in fixed and periodic contacts. Due to the nature of internal combustion engines, the duration of contact between the valve and its seat is too short, and much time is needed to reach the quasi-steady state in the periodic contact between the exhaust valve and its seat. Using the methods of linear extrapolation and the inverse solution, the surface contact temperatures and the fixed and periodic thermal contact conductance were calculated. The results of linear extrapolation and inverse methods have similar trends, and based on the error analysis, they are accurate enough to estimate the thermal contact conductance. Moreover, due to the error analysis, a linear extrapolation method using inverse ratio is preferred. The effects of pressure, contact frequency, heat flux, and cooling air speed on thermal contact conductance have been investigated. The results show that by increasing the contact pressure the thermal contact conductance increases substantially. In addition, by increasing the engine speed the thermal contact conductance decreases. On the other hand, by boosting the air speed the thermal contact conductance increases, and by raising the heat flux the thermal contact conductance reduces. The average calculated error equals to 12.9 %.

  19. Using rapid reviews: an example from a study conducted to inform policy-making.

    PubMed

    O'Leary, Denise F; Casey, Mary; O'Connor, Laserina; Stokes, Diarmuid; Fealy, Gerard M; O'Brien, Denise; Smith, Rita; McNamara, Martin S; Egan, Claire

    2017-03-01

    A discussion of the potential use of rapid review approaches in nursing and midwifery research which presents a worked example from a study conducted to inform policy decision-making. Rapid reviews, which can be defined as outputs of a knowledge synthesis approach that involves modifying or omitting elements of a systematic review process due to limited time or resources, are becoming increasingly popular in health research. This paper provides guidance on how a rapid review can be undertaken and discusses the strengths and challenges of the approach. Data from a rapid review of the literature undertaken in 2015 is used as a worked example to highlight one method of undertaking a rapid review. Seeking evidence to inform health policy-making or evidence based practice is a process that can be limited by time constraints, making it difficult to conduct comprehensive systematic reviews. Rapid reviews provide a solution as they are a systematic method of synthesizing evidence quickly. There is no single best way to conduct a rapid review but researchers can ensure they are adhering to best practice by being systematic, having subject and methodological expertise on the review team, reporting the details of the approach they took, highlighting the limitations of the approach, engaging in good evidence synthesis and communicating regularly with end users, other team members and experts. © 2016 John Wiley & Sons Ltd.

  20. Studies on possibilities of polymer composites with conductive nanomaterials application in wearable electronics

    NASA Astrophysics Data System (ADS)

    Gralczyk, Kinga; Janczak, D.; Dybowska-Sarapuk, Ł.; Lepak, S.; Wróblewski, G.; Jakubowska, M.

    2017-08-01

    In the last few years there has been a growing interest in wearable electronic products, which are generating considerable interest especially in sport and medical industries. But rigid electronics is not comfortable to wear, so things like stretchable substrates, interconnects and electronic devices might help. Flexible electronics could adjust to the curves of a human body and allow the users to move freely. The objective of this paper is to study possibilities of polymer composites with conductive nanomaterials application in wearable electronics. Pastes with graphene, silver nanoplates and carbon nanotubes were manufactured and then interconnects were screen-printed on the surfaces of polyethylene terephthalate (PET) and fabric. Afterwards, the resistance and mechanical properties of samples were examined, also after washing them in a washing machine. It has been found that the best material for the conductive phase is silver. Traces printed directly on the fabric using conductive composites with one functional phase (silver nanoplates or graphene or carbon nanotubes) are too fragile to use them as a common solution in wearable electronics. Mechanical properties can be improved not only by adding carbon nanotubes or graphene to the silver paste, but also by printing additional layer of graphene paste or carbon nanotube paste onto silver layer. In fact, these solutions are not sufficient enough to solve a problem of using these composites in wearable electronics.

  1. Suspension chemistry and electrophoretic deposition of zirconia electrolyte on conducting and non-conducting substrates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Das, Debasish; Basu, Rajendra N., E-mail: rnbasu@cgcri.res.in

    2013-09-01

    Graphical abstract: - Highlights: • Stable suspension of yttria stabilized zirconia (YSZ) obtained in isopropanol medium. • Suspension chemistry and process parameters for electrophoretic deposition optimized. • Deposited film quality changed with iodine and water (dispersants) concentration. • Dense YSZ film (∼5 μm) fabricated onto non-conducting porous NiO-YSZ anode substrate. - Abstract: Suspensions of 8 mol% yttria stabilized zirconia (YSZ) particulates in isopropanol medium are prepared using acetylacetone, iodine and water as dispersants. The effect of dispersants concentration on suspension stability, particle size distribution, electrical conductivity and pH of the suspensions are studied in detail to optimize the suspension chemistry.more » Electrophoretic deposition (EPD) has been conducted to produce thin and dense YSZ electrolyte films. Deposition kinetics have been studied in depth and good quality films on conducting substrate are obtained at an applied voltage of 15 V for 3 min. YSZ films are also fabricated on non-conducting NiO-YSZ anode substrate using a steel plate on the reverse side of the substrate. Upon co-firing at 1400 °C for 6 h a dense YSZ film of thickness ∼5 μm is obtained. Such a half cell (anode + electrolyte) can be used to fabricate a solid oxide fuel cell on applying a suitable cathode layer.« less

  2. The Moderating Effects of Cannabis Use and Decision Making on the Relationship between Conduct Disorder and Risky Sexual Behavior

    PubMed Central

    Ross, J. Megan; Coxe, Stefany; Schuster, Randi M.; Rojas, Angelica; Gonzalez, Raul

    2015-01-01

    Risky sexual behavior (RSB) is a current public health concern affecting adolescents and young adults. Conduct disorder, cannabis use and decision making (DM) ability are interrelated constructs that are relevant to RSB; however, there is little research on the association of DM and RSB. Participants were 79 cannabis users assessed through self-report measures of RSB and mental health, and a timeline follow-back procedure for substance use. DM ability was assessed via the Iowa Gambling Task. We found that more conduct disorder symptoms accounted for unique variance in measures of overall RSB and an earlier initiation of oral sex, even when taking into account DM and cannabis use. Amount of cannabis use and DM ability moderated the relationships between number of conduct disorder symptoms and number of oral sex partners and age of initiation for vaginal sex. An increase in conduct disorder symptoms was associated with more oral sex partners when DM was poor and fewer partners when DM was better, however this relationship was only present at higher levels of cannabis use. Furthermore, when DM was poor, more conduct disorder symptoms predicted a younger age of initiation of vaginal sex, with the age decreasing as amount of cannabis use increased. Determining how DM influences RSB may assist in the identification of novel treatment approaches to reduce engagement in RSB. PMID:25832553

  3. Variable conductance heat pipe technology

    NASA Technical Reports Server (NTRS)

    Marcus, B. D.; Edwards, D. K.; Anderson, W. T.

    1973-01-01

    Research and development programs in variable conductance heat pipe technology were conducted. The treatment has been comprehensive, involving theoretical and/or experimental studies in hydrostatics, hydrodynamics, heat transfer into and out of the pipe, fluid selection, and materials compatibility, in addition to the principal subject of variable conductance control techniques. Efforts were not limited to analytical work and laboratory experimentation, but extended to the development, fabrication and test of spacecraft hardware, culminating in the successful flight of the Ames Heat Pipe Experiment on the OAO-C spacecraft.

  4. Guidance on Conducting and REporting DElphi Studies (CREDES) in palliative care: Recommendations based on a methodological systematic review.

    PubMed

    Jünger, Saskia; Payne, Sheila A; Brine, Jenny; Radbruch, Lukas; Brearley, Sarah G

    2017-09-01

    The Delphi technique is widely used for the development of guidance in palliative care, having impact on decisions with relevance for patient care. To systematically examine the application of the Delphi technique for the development of best practice guidelines in palliative care. A methodological systematic review was undertaken using the databases PubMed, CINAHL, Web of Science, Academic Search Complete and EMBASE. Original articles (English language) were included when reporting on empirical studies that had used the Delphi technique to develop guidance for good clinical practice in palliative care. Data extraction included a quality appraisal on the rigour in conduct of the studies and the quality of reporting. A total of 30 empirical studies (1997-2015) were considered for full-text analysis. Considerable differences were identified regarding the rigour of the design and the reporting of essential process and outcome parameters. Furthermore, discrepancies regarding the use of terms for describing the method were observed, for example, concerning the understanding of a 'round' or a 'modified Delphi study'. Substantial variation was found concerning the quality of the study conduct and the transparency of reporting of Delphi studies used for the development of best practice guidance in palliative care. Since credibility of the resulting recommendations depends on the rigorous use of the Delphi technique, there is a need for consistency and quality both in the conduct and reporting of studies. To allow a critical appraisal of the methodology and the resulting guidance, a reporting standard for Conducting and REporting of DElphi Studies (CREDES) is proposed.

  5. Impact of 6-month earlier versus postponed initiation of rotigotine on long-term outcome: post hoc analysis of patients with early Parkinson's disease with mild symptom severity.

    PubMed

    Timmermann, Lars; Asgharnejad, Mahnaz; Boroojerdi, Babak; Dohin, Elisabeth; Woltering, Franz; Elmer, Lawrence W

    2015-01-01

    Investigate impact of 6-month earlier versus postponed initiation of rotigotine in patients with early Parkinson's disease (PD) with mild symptom severity. Long-term benefit of rotigotine in early-PD has been demonstrated: SP702 (NCT00594165) and SP716 (NCT00599196) were long-term, open-label extensions of double-blind, placebo-controlled studies of 6-month maintenance; rotigotine was well tolerated for up to 6 years, and demonstrated efficacy (Unified Parkinson's Disease Rating Scale [UPDRS] II + III below baseline) for ∼ 2 years (SP702) and ∼ 4 years (SP716). Post hoc analysis of patients at Hoehn and Yahr 1-2; groups defined by treatment received in 6-month double-blind studies: 'Rotigotine-Rotigotine' received rotigotine (n = 221), 'Placebo-Rotigotine' received placebo (n = 125). At the start of open-label rotigotine maintenance, UPDRS II + III mean ± SD change from double-blind baseline was: -8.5 ± 10.6 'Rotigotine-Rotigotine', -7.7 ± 9.0 'Placebo-Rotigotine.' After this initial improvement scores gradually increased: It took ∼ 45 months for mean scores to cross baseline in 'Rotigotine-Rotigotine', and ∼ 21 months in 'Placebo-Rotigotine.' At the time mean UPDRS II + III had crossed baseline in 'Placebo-Rotigotine' (open-label week 84; ∼ 21 months), treatment difference (LS-mean) to 'Rotigotine-Rotigotine' change from baseline was -3.89 (95% CI -6.94, -0.84); p = 0.013. In this post hoc analysis, 6-month earlier initiation of rotigotine resulted in slower return to baseline mean UPDRS II + III; initiation of rotigotine in patients with minimal/no functional disability or impairment may lead to an extended benefit.

  6. Electrowetting on dielectric: experimental and model study of oil conductivity on rupture voltage

    NASA Astrophysics Data System (ADS)

    Zhao, Qing; Tang, Biao; Dong, Baoqin; Li, Hui; Zhou, Rui; Guo, Yuanyuan; Dou, Yingying; Deng, Yong; Groenewold, Jan; Henzen, Alexander Victor; Zhou, Guofu

    2018-05-01

    Electrowetting on dielectric devices uses a conducting (water) and insulating (oil) liquid phase in conjunction on a dielectric layer. In these devices, the wetting properties of the liquid phases can be manipulated by applying an electric field. The electric field can rupture the initially flat oil film and promotes further dewetting of the oil. Here, we investigate a problem in the operation of electrowetting on dielectric caused by a finite conductivity of the oil. In particular, we find that the voltage at which the oil film ruptures is sensitive to the application of relatively low DC voltages prior to switching. Here, we systematically investigate this dependence using controlled driving schemes. The mechanism behind these history effects point to charge transport processes in the dielectric and the oil, which can be modeled and characterized by a decay time. To quantify the effects the typical response timescales have been measured with a high-speed video camera. The results have been reproduced in simulations. In addition, a simplified yet accurate equivalent circuit model is developed to analyze larger data sets more conveniently. The experimental data support the hypothesis that each pixel can be characterized by a single decay time. We studied an ensemble of pixels and found that they showed a rather broad distribution of decay times with an average value of about 440 ms. This decay time can be interpreted as a discharge timescale of the oil, not to be confused with discharge of the entire system which is generally much faster (<1 ms). Through the equivalent circuit model, we also found that variations in the fluoropolymer (FP) conductivity cannot explain the distribution of decay times, while variations in oil conductivity can.

  7. COLUMN STUDIES ON BTEX BIODEGRADATION UNDER MICROAEROPHILIC AND DENITRIFYING CONDITIONS

    EPA Science Inventory

    Two column tests were conducted using aquifer material to simulate the nitrate field demonstration project carried out earlier at Traverse City, Michigan. The objectives were to better define the effect nitrate addition had on biodegradation of benzene, toluene, ethylbenzene, xyl...

  8. Regulation of Conduction Time along Axons

    PubMed Central

    Seidl, Armin H.

    2013-01-01

    Timely delivery of information is essential for proper function of the nervous system. Precise regulation of nerve conduction velocity is needed for correct exertion of motor skills, sensory integration and cognitive functions. In vertebrates, the rapid transmission of signals along nerve fibers is made possible by the myelination of axons and the resulting saltatory conduction in between nodes of Ranvier. Myelin is a specialization of glia cells and is provided by oligodendrocytes in the central nervous system. Myelination not only maximizes conduction velocity, but also provides a means to systematically regulate conduction times in the nervous system. Systematic regulation of conduction velocity along axons, and thus systematic regulation of conduction time in between neural areas, is a common occurrence in the nervous system. To date, little is understood about the mechanism that underlies systematic conduction velocity regulation and conduction time synchrony. Node assembly, internode distance (node spacing) and axon diameter - all parameters determining the speed of signal propagation along axons - are controlled by myelinating glia. Therefore, an interaction between glial cells and neurons has been suggested. This review summarizes examples of neural systems in which conduction velocity is regulated by anatomical variations along axons. While functional implications in these systems are not always clear, recent studies in the auditory system of birds and mammals present examples of conduction velocity regulation in systems with high temporal precision and a defined biological function. Together these findings suggest an active process that shapes the interaction between axons and myelinating glia to control conduction velocity along axons. Future studies involving these systems may provide further insight into how specific conduction times in the brain are established and maintained in development. Throughout the text, conduction velocity is used for the

  9. Experimental Study on Thermal Conductivity of Self-Compacting Concrete with Recycled Aggregate.

    PubMed

    Fenollera, María; Míguez, José Luis; Goicoechea, Itziar; Lorenzo, Jaime

    2015-07-20

    The research focuses on the use of recycled aggregate (RA), from waste pieces generated during production in precast plants for self-compacting concrete (SCC) manufactured with a double sustainable goal: recycle manufacturing waste (consumption) and improvement of the thermal properties of the manufactured product (energy efficiency). For this purpose, a mechanical study to ensure technical feasibility of the concrete obtained has been conducted, as well as a thermal analysis of recycled SCC specimens of 50 N/mm² resistance, with different RA doses (0%, 20%, 50% and 100%). The main parameters that characterize a SCC in both states, fresh (slump-flow) and hard (compressive strength), have been tested; also, a qualitative analysis of the thermal conductivity using infrared thermography (IRT) and quantitative analysis with heat flow meter at three temperatures 20 °C, 25 °C and 30 °C have been performed. The results suggest the existence of two different thermal behaviors: concretes with 0% and 20% of RA, and on the other hand concretes with 50% and 100% of RA. It has also demonstrated the validity of the IRT as sampling technique in estimating the thermal behavior of materials having reduced range of variation in parameters.

  10. Conducting pilot and feasibility studies.

    PubMed

    Cope, Diane G

    2015-03-01

    Planning a well-designed research study can be tedious and laborious work. However, this process is critical and ultimately can produce valid, reliable study findings. Designing a large-scale randomized, controlled trial (RCT)-the gold standard in quantitative research-can be even more challenging. Even the most well-planned study potentially can result in issues with research procedures and design, such as recruitment, retention, or methodology. One strategy that may facilitate sound study design is the completion of a pilot or feasibility study prior to the initiation of a larger-scale trial. This article will discuss pilot and feasibility studies, their advantages and disadvantages, and implications for oncology nursing research. 
.

  11. Machine learning with neural networks - a case study of estimating thermal conductivity with ancient well-log data

    NASA Astrophysics Data System (ADS)

    Harrison, Benjamin; Sandiford, Mike; McLaren, Sandra

    2016-04-01

    Supervised machine learning algorithms attempt to build a predictive model using empirical data. Their aim is to take a known set of input data along with known responses to the data, and adaptively train a model to generate predictions for new data inputs. A key attraction to their use is the ability to perform as function approximators where the definition of an explicit relationship between variables is infeasible. We present a novel means of estimating thermal conductivity using a supervised self-organising map algorithm, trained on about 150 thermal conductivity measurements, and using a suite of five electric logs common to 14 boreholes. A key motivation of the study was to supplement the small number of direct measurements of thermal conductivity with the decades of borehole data acquired in the Gippsland Basin to produce more confident calculations of surface heat flow. A previous attempt to generate estimates from well-log data in the Gippsland Basin using classic petrophysical log interpretation methods was able to produce reasonable synthetic thermal conductivity logs for only four boreholes. The current study has extended this to a further ten boreholes. Interesting outcomes from the study are: the method appears stable at very low sample sizes (< ~100); the SOM permits quantitative analysis of essentially qualitative uncalibrated well-log data; and the method's moderate success at prediction with minimal effort tuning the algorithm's parameters.

  12. Intracochlear pressure measurements to study bone conduction transmission: State-of-the art and proof of concept of the experimental Procedure

    NASA Astrophysics Data System (ADS)

    Borgers, Charlotte; van Wieringen, Astrid; D'hondt, Christiane; Verhaert, Nicolas

    2018-05-01

    The cochlea is the main contributor in bone conduction perception. Measurements of differential pressure in the cochlea give a good estimation of the cochlear input provided by bone conduction stimulation. Recent studies have proven the feasibility of intracochlear pressure measurements in chinchillas and in human temporal bones to study bone conduction. However, similar measurements in fresh-frozen whole human cadaveric heads could give a more realistic representation of the five different transmission pathways of bone conduction to the cochlea compared to human temporal bones. The aim of our study is to develop and validate a framework for intracochlear pressure measurements to evaluate different aspects of bone conduction in whole human cadaveric heads. A proof of concept describing our experimental setup is provided together with the procedure. Additionally, we also present a method to fix the stapes footplate in order to simulate otosclerosis in human temporal bones. The effectiveness of this method is verified by some preliminary results.

  13. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How can I request assistance to conduct a feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Overview § 404.18 How can I...

  14. Qualitative Research and Educational Leadership: Essential Dynamics to Consider When Designing and Conducting Studies

    ERIC Educational Resources Information Center

    Brooks, Jeffrey S.; Normore, Anthony H.

    2015-01-01

    Purpose: The purpose of this paper is to highlight issues relayed to appropriate design and conduct of qualitative studies in educational leadership. Design/Methodology/Approach: The paper is a conceptual/logical argument that centers around the notion that while scholars in the field have at times paid attention to such dynamics, it is important…

  15. Role of succinonitrile in improving ionic conductivity of sodium-ion conductive polymer electrolyte

    NASA Astrophysics Data System (ADS)

    Nair, Manjula G.; Mohapatra, Saumya R.

    2018-05-01

    Sodium ion conducting solid polymer electrolytes were prepared using poly (ethylene oxide) (PEO) as polymer matrix, sodium perchlorate (NaClO4) as salt and succinonitrile (SN) as a plasticizer by solution casting technique. By blending a plastic crystal such as succinonitrile (SN) with PEO-NaClO4 electrolyte system, we aimed at improving the ionic conductivity by weakening the ether oxygen-Na+ interactions. The XRD and FTIR studies revealed structural and micro-structural changes in the blended electrolytes which aids in improving ionic conductivity. Also, DSC measurements showed improved segmental motion in the blended polymer electrolytes due to plasticizing effect of SN. The maximum ionic conductivity observed at room temperature is 1.13×10-5 S cm-1 merely for 7 wt. % of SN, which is one order higher than pure polymer-salt complex. The thermo-gravimetric analysis (TGA) suggests that blending of SN with polymer electrolyte had no detrimental effect on its thermal stability.

  16. Dielectric and AC conductivity studies on SrBi4Ti4O15

    NASA Astrophysics Data System (ADS)

    Jose, Roshan; Saravanan, K. Venkata

    2018-05-01

    The four layered SrBi4Ti4O15 ceramics which belong to the aurivillius family of oxide was prepared by conventional solid state reaction technique. Analysis of the dielectric data as a function of temperature and frequency revealed normal phase transition. The frequency dependent ac conductivity follows Jonscher's universal power law. Frequency exponent (n), pre-exponential factor (A), bulk dc conductivity (σdc), and hopping frequency (ωp) were determined from the fitting curves. The variation of frequency exponent with temperature indicates that large polaron hopping mechanism up to curie-temperature, then its changes to small polaron hopping. The activation energies were calculated from ac conductivity, bulk dc conductivity and hopping frequency. The activation energies revealed that conductivity had contributions from migrations of oxygen vacancies, bismuth ion vacancies and strontium ion vacancies.

  17. 34 CFR 413.33 - What substantive studies must the National Center or Centers conduct and submit?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Secretary of Labor, the Secretary of Health and Human Services, the Committee on Labor and Human Resources... apprenticeship or mentoring approaches. (b) The National Center conducting dissemination and training activities shall annually prepare a study of its dissemination and training activities. (c) Annual studies...

  18. Stability study: Transparent conducting oxides in chemically reactive plasmas

    NASA Astrophysics Data System (ADS)

    Manjunatha, Krishna Nama; Paul, Shashi

    2017-12-01

    Effect of plasma treatment on transparent conductive oxides (TCOs) including indium-doped tin oxide (ITO), fluorine-doped tin oxide (FTO) and aluminium-doped zinc oxide (AZO) are discussed. Stability of electrical and optical properties of TCOs, when exposed to plasma species generated from gases such as hydrogen and silane, are studied extensively. ITO and FTO thin films are unstable and reduce to their counterparts such as Indium and Tin when subjected to plasma. On the other hand, AZO is not only stable but also shows superior electrical and optical properties. The stability of AZO makes it suitable for electronic applications, such as solar cells and transistors that are fabricated under plasma environment. TCOs exposed to plasma with different fabrication parameters are used in the fabrication of silicon nanowire solar cells. The performance of solar cells, which is mired by the plasma, fabricated on ITO and FTO is discussed with respect to plasma exposure parameters while showing the advantages of using chemically stable AZO as an ideal TCO for solar cells. Additionally, in-situ diagnostic tool (optical emission spectroscopy) is used to monitor the deposition process and damage caused to TCOs.

  19. Excess protons in water-acetone mixtures. II. A conductivity study.

    PubMed

    Semino, Rocío; Longinotti, M Paula

    2013-10-28

    In the present work we complement a previous simulation study [R. Semino and D. Laria, J. Chem. Phys. 136, 194503 (2012)] on the disruption of the proton transfer mechanism in water by the addition of an aprotic solvent, such as acetone. We provide experimental measurements of the mobility of protons in aqueous-acetone mixtures in a wide composition range, for water molar fractions, xw, between 0.05 and 1.00. Furthermore, new molecular dynamics simulation results are presented for rich acetone mixtures, which provide further insight into the proton transport mechanism in water-non-protic solvent mixtures. The proton mobility was analyzed between xw 0.05 and 1.00 and compared to molecular dynamics simulation data. Results show two qualitative changes in the proton transport composition dependence at xw ∼ 0.25 and 0.8. At xw < 0.25 the ratio of the infinite dilution molar conductivities of HCl and LiCl, Λ(0)(HCl).Λ(0)(LiCl)(-1), is approximately constant and equal to one, since the proton diffusion is vehicular and equal to that of Li(+). At xw ∼ 0.25, proton mobility starts to differ from that of Li(+) indicating that above this concentration the Grotthuss transport mechanism starts to be possible. Molecular dynamics simulation results showed that at this threshold concentration the probability of interconversion between two Eigen structures starts to be non-negligible. At xw ∼ 0.8, the infinite molar conductivity of HCl concentration dependence qualitatively changes. This result is in excellent agreement with the analysis presented in the previous simulation work and it has been ascribed to the interchange of water and acetone molecules in the second solvation shell of the hydronium ion.

  20. Phrenic Nerve Conduction Study in the Early Stage of Guillain-Barre Syndrome as a Predictor of Respiratory Failure.

    PubMed

    Sen, Barun Kumar; Pandit, Alak

    2018-01-01

    Guillain-Barré syndrome (GBS) has unpredictable clinical course with severe complication of respiratory failure. To identify clinical profiles and electrophysiological study particularly non-invasive Phrenic nerve conduction study in patients of early GBS to predict respiratory failure. 64 adult (age≥18yrs) patients of early GBS (onset ≤ 14 days) during the study period from January 2014 to October 2015 were evaluated by clinical profiles of age, gender, antecedent infection, time to peak disability, single breath counts, cranial nerve involvement, autonomic dysfunction and non-invasive Phrenic nerve conduction study. Patients with predisposition factors of polyneuropathy like diabetes mellitus, hypothyroidism, vitamin deficiency, renal failure were excluded. Among 64 patients abnormal phrenic nerve conduction study was seen in 65.62% cases (42/64) and 45.23% (19/42) of them developed respiratory failure. Phrenic nerve sum latency, amplitude, duration and area were abnormal in those who developed respiratory failure and they had sum of phrenic nerve latency >28 msec, sum of CMAP amplitude <300 μV, sum of CMAP duration >50 msec and sum of area < 4 mVmS. None with normal phrenic nerve study developed respiratory failure. It was found that age, gender, preceding infection, autonomic involvement and types of GB syndrome had no influence on development of respiratory failure (p>0.05). Rapid disease progression to peak disability, more severe disease, shorter single breath counts and cranial nerve involvement were seen more often in patients with respiratory failure. Abnormal Phrenic nerve conduction study in the early Guillain-Barré syndrome might be of great value independently in predicting impending respiratory failure.