Exome sequencing of extreme phenotypes identifies DCTN4 as a modifier of chronic Pseudomonas aeruginosa infection in cystic fibrosis.

PubMed

Emond, Mary J; Louie, Tin; Emerson, Julia; Zhao, Wei; Mathias, Rasika A; Knowles, Michael R; Wright, Fred A; Rieder, Mark J; Tabor, Holly K; Nickerson, Deborah A; Barnes, Kathleen C; Gibson, Ronald L; Bamshad, Michael J

2012-07-08

Exome sequencing has become a powerful and effective strategy for the discovery of genes underlying Mendelian disorders. However, use of exome sequencing to identify variants associated with complex traits has been more challenging, partly because the sample sizes needed for adequate power may be very large. One strategy to increase efficiency is to sequence individuals who are at both ends of a phenotype distribution (those with extreme phenotypes). Because the frequency of alleles that contribute to the trait are enriched in one or both phenotype extremes, a modest sample size can potentially be used to identify novel candidate genes and/or alleles. As part of the National Heart, Lung, and Blood Institute (NHLBI) Exome Sequencing Project (ESP), we used an extreme phenotype study design to discover that variants in DCTN4, encoding a dynactin protein, are associated with time to first P. aeruginosa airway infection, chronic P. aeruginosa infection and mucoid P. aeruginosa in individuals with cystic fibrosis.

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

Pahl, R. J.; Trott, W. M.; Snedigar, S.

A series of gas gun tests has been performed to examine contributions to energy release from micron-sized and nanometric aluminum powder added to sieved (212-300{mu}m) HMX. In the absence of added metal, 4-mm-thick, low-density (64-68% of theoretical maximum density) pressings of the sieved HMX respond to modest shock loading by developing distinctive reactive waves that exhibit both temporal and mesoscale spatial fluctuations. Parallel tests have been performed on samples containing 10% (by mass) aluminum in two particle sizes: 2-{mu}m and 123-nm mean particle diameter, respectively. The finely dispersed aluminum initially suppresses wave growth from HMX reactions; however, after a visiblemore » induction period, the added metal drives rapid increases in the transmitted wave particle velocity. Wave profile variations as a function of the aluminum particle diameter are discussed.« less

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

Castaneda, Jaime N.; Pahl, Robert J.; Snedigar, Shane

A series of gas gun tests has been performed to examine contributions to energy release from micron-sized and nanometric aluminum powder added to sieved (212-300{micro}m) HMX. In the absence of added metal, 4-mm-thick, low-density (64-68% of theoretical maximum density) pressings of the sieved HMX respond to modest shock loading by developing distinctive reactive waves that exhibit both temporal and mesoscale spatial fluctuations. Parallel tests have been performed on samples containing 10% (by mass) aluminum in two particle sizes: 2-{micro}m and 123-nm mean particle diameter, respectively. The finely dispersed aluminum initially suppresses wave growth from HMX reactions; however, after a visiblemore » induction period, the added metal drives rapid increases in the transmitted wave particle velocity. Wave profile variations as a function of the aluminum particle diameter are discussed.« less

Orbital Debris Research in the United States

NASA Technical Reports Server (NTRS)

Stansbery, Gene

2009-01-01

The presentation includes information about growth of the satellite population, the U.S. Space Surveillance Network, tracking and catalog maintenance, Haystack and HAX radar observation, Goldstone radar, the Michigan Orbital Debris Survey Telescope (MODEST), spacecraft surface examinations and sample of space shuttle impacts. GEO/LEO observations from Kwajalein Atoll, NASA s Orbital Debris Engineering Model (ORDEM2008), a LEO-to-GEO Environment Debris Model (LEGEND), Debris Assessment Software (DAS) 2.0, the NASA/JSC BUMPER-II meteoroid/debris threat assessment code, satellite reentry risk assessment, optical size and shape determination, work on more complicated fragments, and spectral studies.

Maraia Capsule Flight Testing and Results for Entry, Descent, and Landing

NASA Technical Reports Server (NTRS)

Sostaric, Ronald R.; Strahan, Alan L.

2016-01-01

The Maraia concept is a modest size (150 lb., 30" diameter) capsule that has been proposed as an ISS based, mostly autonomous earth return capability to function either as an Entry, Descent, and Landing (EDL) technology test platform or as a small on-demand sample return vehicle. A flight test program has been completed including high altitude balloon testing of the proposed capsule shape, with the purpose of investigating aerodynamics and stability during the latter portion of the entry flight regime, along with demonstrating a potential recovery system. This paper includes description, objectives, and results from the test program.

Effects of psycho-behavioral interventions on immune functioning in cancer patients: a systematic review.

PubMed

Tong, Guixian; Geng, Qingqing; Cheng, Jing; Chai, Jing; Xia, Yi; Feng, Rui; Zhang, Lu; Wang, Debin

2014-01-01

This study aimed at summarizing evidence about effects of psycho-behavioral interventions (PBIs) on immune responses among cancer patients and analyzing quality of published studies so as to inform future researches. Literature retrieval utilized both highly inclusive algorithms searching randomized controlled studies published in English and Chinese and manual searching of eligible studies from references of relevant review papers. Two researchers examined the articles selected separately and extracted the information using a pre-designed form for soliciting data about the trials (e.g., sample size, disease status, intervention, immune responses) and quality ratings of the studies. Both narrative descriptions and meta-analysis (via Review manager 5) were used synthesizing the effects of PBIs on immune responses among cancer patients and state of art of the researches in this area. Seventy-six RCTs met inclusion criteria. PBIs implemented were divided into three major categories including psychological state adjustment, physical activity and dietary modification. Immune indicators measured included CD4+ cells, CD8+ cells, CD4/CDC8+ ratio, CD3+ cells, NK cell activity, etc. Effects of PBIs on immune responses documented in individual papers were mixed and pooled analysis of CD4+ cells, CD4+/CD8+ ratio, CD3+ cells, NKCA, IgG, IgM and IL-2 showed modest effects. However, there were huge discrepancies in intervention effects between studies published in English and Chinese and the results should be interpreted with caution. Besides, most studies suffer from some quality flaws concerning blinding, randomization procedures, compliance, attrition and intention-to-treat analyses, etc. Although there are considerable evidences of PBI effects on some immune indicators, the effect sizes are modest and it is still premature to conclude whether PBIs have effects on immune functions among cancer patients. There is a clear need for much more rigorous efforts in this area and future researches should pay particular attention to intervention dose and focus, sample size and comparable immune measures.

Testosterone in human studies: Modest associations between plasma and salivary measurements.

PubMed

de Wit, A E; Bosker, F J; Giltay, E J; de Kloet, C S; Roelofs, K; van Pelt, J; Penninx, B W J H; Schoevers, R A

2018-02-01

Testosterone is involved in many processes like aggression and mood disorders. As it may easily diffuse from blood into saliva, salivary testosterone is thought to reflect plasma free testosterone level. If so, it would provide a welcome noninvasive and less stressful alternative to blood sampling. Past research did not reveal consensus regarding the strength of the association, but sample sizes were small. This study aimed to analyse the association in a large cohort. In total, 2,048 participants (age range 18-65 years; 696 males and 1,352 females) were included and saliva (using cotton Salivettes) and plasma were collected for testosterone measurements. Levels were determined by enzyme-linked immunosorbent assay and radioimmunoassay respectively. Free testosterone was calculated by the Vermeulen algorithm. Associations were determined using linear regression analyses. Plasma total and free testosterone showed a significant association with salivary testosterone in men (adjusted β = .09, p = .01; and β = .15, p < .001, respectively) and in women (adjusted β = .08, p = .004; and crude β = .09, p = .002 respectively). The modest associations indicate that there are many influencing factors of both technical and biological origin. © 2017 Blackwell Verlag GmbH.

A genome-wide association study implicates diacylglycerol kinase eta (DGKH) and several other genes in the etiology of bipolar disorder

PubMed Central

Baum, AE; Akula, N; Cabanero, M; Cardona, I; Corona, W; Klemens, B; Schulze, TG; Cichon, S; Rietschel, M; Nöthen, MM; Georgi, A; Schumacher, J; Schwarz, M; Jamra, R Abou; Höfels, S; Propping, P; Satagopan, J; Detera-Wadleigh, SD; Hardy, J; McMahon, FJ

2008-01-01

The genetic basis of bipolar disorder has long been thought to be complex, with the potential involvement of multiple genes, but methods to analyze populations with respect to this complexity have only recently become available. We have carried out a genome-wide association study of bipolar disorder by genotyping over 550,000 SNPs in two independent case-control samples of European origin. The initial association screen was performed using pooled DNA; selected SNPs were confirmed by individual genotyping. While DNA pooling reduces power to detect genetic associations, there is a substantial cost savings and gain in efficiency. A total of 88 SNPs representing 80 different genes met the prior criteria for replication in both samples. Effect sizes were modest: no single SNP of large effect was detected. Of 37 SNPs selected for individual genotyping, the strongest association signal was detected at a marker within the first intron of DGKH (p = 1.5 × 10−8, experiment-wide p<0.01, OR= 1.59). This gene encodes diacylglycerol kinase eta, a key protein in the lithium-sensitive phosphatidyl inositol pathway. This first genome-wide association study of bipolar disorder shows that several genes, each of modest effect, reproducibly influence disease risk. Bipolar disorder may be a polygenic disease. PMID:17486107

Valuing Trial Designs from a Pharmaceutical Perspective Using Value-Based Pricing.

PubMed

Breeze, Penny; Brennan, Alan

2015-11-01

Our aim was to adapt the traditional framework for expected net benefit of sampling (ENBS) to be more compatible with drug development trials from the pharmaceutical perspective. We modify the traditional framework for conducting ENBS and assume that the price of the drug is conditional on the trial outcomes. We use a value-based pricing (VBP) criterion to determine price conditional on trial data using Bayesian updating of cost-effectiveness (CE) model parameters. We assume that there is a threshold price below which the company would not market the new intervention. We present a case study in which a phase III trial sample size and trial duration are varied. For each trial design, we sampled 10,000 trial outcomes and estimated VBP using a CE model. The expected commercial net benefit is calculated as the expected profits minus the trial costs. A clinical trial with shorter follow-up, and larger sample size, generated the greatest expected commercial net benefit. Increasing the duration of follow-up had a modest impact on profit forecasts. Expected net benefit of sampling can be adapted to value clinical trials in the pharmaceutical industry to optimise the expected commercial net benefit. However, the analyses can be very time consuming for complex CE models. © 2014 The Authors. Health Economics published by John Wiley & Sons Ltd.

Surface ocean metabarcoding confirms limited diversity in planktonic foraminifera but reveals unknown hyper-abundant lineages.

PubMed

Morard, Raphaël; Garet-Delmas, Marie-José; Mahé, Frédéric; Romac, Sarah; Poulain, Julie; Kucera, Michal; de Vargas, Colomban

2018-02-07

Since the advent of DNA metabarcoding surveys, the planktonic realm is considered a treasure trove of diversity, inhabited by a small number of abundant taxa, and a hugely diverse and taxonomically uncharacterized consortium of rare species. Here we assess if the apparent underestimation of plankton diversity applies universally. We target planktonic foraminifera, a group of protists whose known morphological diversity is limited, taxonomically resolved and linked to ribosomal DNA barcodes. We generated a pyrosequencing dataset of ~100,000 partial 18S rRNA foraminiferal sequences from 32 size fractioned photic-zone plankton samples collected at 8 stations in the Indian and Atlantic Oceans during the Tara Oceans expedition (2009-2012). We identified 69 genetic types belonging to 41 morphotaxa in our metabarcoding dataset. The diversity saturated at local and regional scale as well as in the three size fractions and the two depths sampled indicating that the diversity of foraminifera is modest and finite. The large majority of the newly discovered lineages occur in the small size fraction, neglected by classical taxonomy. These unknown lineages dominate the bulk [>0.8 µm] size fraction, implying that a considerable part of the planktonic foraminifera community biomass has its origin in unknown lineages.

Population-Based Resequencing of Experimentally Evolved Populations Reveals the Genetic Basis of Body Size Variation in Drosophila melanogaster

PubMed Central

Turner, Thomas L.; Stewart, Andrew D.; Fields, Andrew T.; Rice, William R.; Tarone, Aaron M.

2011-01-01

Body size is a classic quantitative trait with evolutionarily significant variation within many species. Locating the alleles responsible for this variation would help understand the maintenance of variation in body size in particular, as well as quantitative traits in general. However, successful genome-wide association of genotype and phenotype may require very large sample sizes if alleles have low population frequencies or modest effects. As a complementary approach, we propose that population-based resequencing of experimentally evolved populations allows for considerable power to map functional variation. Here, we use this technique to investigate the genetic basis of natural variation in body size in Drosophila melanogaster. Significant differentiation of hundreds of loci in replicate selection populations supports the hypothesis that the genetic basis of body size variation is very polygenic in D. melanogaster. Significantly differentiated variants are limited to single genes at some loci, allowing precise hypotheses to be formed regarding causal polymorphisms, while other significant regions are large and contain many genes. By using significantly associated polymorphisms as a priori candidates in follow-up studies, these data are expected to provide considerable power to determine the genetic basis of natural variation in body size. PMID:21437274

A group sequential adaptive treatment assignment design for proof of concept and dose selection in headache trials.

PubMed

Hall, David B; Meier, Ulrich; Diener, Hans-Cristoph

2005-06-01

The trial objective was to test whether a new mechanism of action would effectively treat migraine headaches and to select a dose range for further investigation. The motivation for a group sequential, adaptive, placebo-controlled trial design was (1) limited information about where across the range of seven doses to focus attention, (2) a need to limit sample size for a complicated inpatient treatment and (3) a desire to reduce exposure of patients to ineffective treatment. A design based on group sequential and up and down designs was developed and operational characteristics were explored by trial simulation. The primary outcome was headache response at 2 h after treatment. Groups of four treated and two placebo patients were assigned to one dose. Adaptive dose selection was based on response rates of 60% seen with other migraine treatments. If more than 60% of treated patients responded, then the next dose was the next lower dose; otherwise, the dose was increased. A stopping rule of at least five groups at the target dose and at least four groups at that dose with more than 60% response was developed to ensure that a selected dose would be statistically significantly (p=0.05) superior to placebo. Simulations indicated good characteristics in terms of control of type 1 error, sufficient power, modest expected sample size and modest bias in estimation. The trial design is attractive for phase 2 clinical trials when response is acute and simple, ideally binary, placebo comparator is required, and patient accrual is relatively slow allowing for the collection and processing of results as a basis for the adaptive assignment of patients to dose groups. The acute migraine trial based on this design was successful in both proof of concept and dose range selection.

Leveraging the Happy Meal Effect: Substituting Food with Modest Nonfood Incentives Decreases Portion Size Choice

PubMed Central

Reimann, Martin; Bechara, Antoine; MacInnis, Deborah

2015-01-01

Despite much effort to decrease food intake by altering portion sizes, “super-sized” meals are the preferred choice of many. This research investigated the extent to which individuals can be subtly incentivized to choose smaller portion sizes. Three randomized experiments (2 in the lab and 1 in the field) established that individuals’ choice of full-sized food portions is reduced when they are given the opportunity to choose a half-sized version with a modest nonfood incentive. This substitution effect was robust across different nonfood incentives, foods, populations, and time. Experiment 1 established the effect with children, using inexpensive headphones as nonfood incentives. Experiment 2—a longitudinal study across multiple days—generalized this effect with adults, using the mere chance to win either gift cards or frequent flyer miles as nonfood incentives. Experiment 3 demonstrated the effect among actual restaurant customers who had originally planned to eat a full-sized portion, using the mere chance to win small amounts of money. Our investigation broadens the psychology of food portion choice from perceptual and social factors to motivational determinants. PMID:26372082

Dental size variation in the Atapuerca-SH Middle Pleistocene hominids.

PubMed

Bermúdez de Castro, J M; Sarmiento, S; Cunha, E; Rosas, A; Bastir, M

2001-09-01

The Middle Pleistocene Atapuerca-Sima de los Huesos (SH) site in Spain has yielded the largest sample of fossil hominids so far found from a single site and belonging to the same biological population. The SH dental sample includes a total of 452 permanent and deciduous teeth, representing a minimum of 27 individuals. We present a study of the dental size variation in these hominids, based on the analysis of the mandibular permanent dentition: lateral incisors, n=29; canines, n=27; third premolars, n=30; fourth premolars, n=34; first molars, n=38; second molars, n=38. We have obtained the buccolingual diameter and the crown area (measured on occlusal photographs) of these teeth, and used the bootstrap method to assess the amount of variation in the SH sample compared with the variation of a modern human sample from the Museu Antropologico of the Universidade of Coimbra (Portugal). The SH hominids have, in general terms, a dental size variation higher than that of the modern human sample. The analysis is especially conclusive for the canines. Furthermore, we have estimated the degree of sexual dimorphism of the SH sample by obtaining male and female dental subsamples by means of sexing the large sample of SH mandibular specimens. We obtained the index of sexual dimorphism (ISD=male mean/female mean) and the values were compared with those obtained from the sexed modern human sample from Coimbra, and with data found in the literature concerning several recent human populations. In all tooth classes the ISD of the SH hominids was higher than that of modern humans, but the differences were generally modest, except for the canines, thus suggesting that canine size sexual dimorphism in Homo heidelbergensis was probably greater than that of modern humans. Since the approach of sexing fossil specimens has some obvious limitations, these results should be assessed with caution. Additional data from SH and other European Middle Pleistocene sites would be necessary to test this hypothesis. Copyright 2001 Academic Press.

How important are work-family support policies? A meta-analytic investigation of their effects on employee outcomes.

PubMed

Butts, Marcus M; Casper, Wendy J; Yang, Tae Seok

2013-01-01

This meta-analysis examines relationships between work-family support policies, which are policies that provide support for dependent care responsibilities, and employee outcomes by developing a conceptual model detailing the psychological mechanisms through which policy availability and use relate to work attitudes. Bivariate results indicated that availability and use of work-family support policies had modest positive relationships with job satisfaction, affective commitment, and intentions to stay. Further, tests of differences in effect sizes showed that policy availability was more strongly related to job satisfaction, affective commitment, and intentions to stay than was policy use. Subsequent meta-analytic structural equation modeling results indicated that policy availability and use had modest effects on work attitudes, which were partially mediated by family-supportive organization perceptions and work-to-family conflict, respectively. Additionally, number of policies and sample characteristics (percent women, percent married-cohabiting, percent with dependents) moderated the effects of policy availability and use on outcomes. Implications of these findings and directions for future research on work-family support policies are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Effect of pectin methylesterase on carrot (Daucus carota) juice cloud stability.

PubMed

Schultz, Alison K; Anthon, Gordon E; Dungan, Stephanie R; Barrett, Diane M

2014-02-05

To determine the effect of residual enzyme activity on carrot juice cloud, 0 to 1 U/g pectin methylesterase (PME) was added to pasteurized carrot juice. Cloud stability and particle diameters were measured to quantify juice cloud stability and clarification for 56 days of storage. All levels of PME addition resulted in clarification; higher amounts had a modest effect in causing more rapid clarification, due to a faster increase in particle size. The cloud initially exhibited a trimodal distribution of particle sizes. For enzyme-containing samples, particles in the smallest-sized mode initially aggregated to merge with the second peak over 5-10 days. This larger population then continued to aggregate more slowly over longer times. This observation of a more rapid destabilization process initially, followed by slower subsequent changes in the cloud, was also manifested in measurements of sedimentation extent and in turbidity tests. Optical microscopy showed that aggregation created elongated, fractal particle structures over time.

SIproc: an open-source biomedical data processing platform for large hyperspectral images.

PubMed

Berisha, Sebastian; Chang, Shengyuan; Saki, Sam; Daeinejad, Davar; He, Ziqi; Mankar, Rupali; Mayerich, David

2017-04-10

There has recently been significant interest within the vibrational spectroscopy community to apply quantitative spectroscopic imaging techniques to histology and clinical diagnosis. However, many of the proposed methods require collecting spectroscopic images that have a similar region size and resolution to the corresponding histological images. Since spectroscopic images contain significantly more spectral samples than traditional histology, the resulting data sets can approach hundreds of gigabytes to terabytes in size. This makes them difficult to store and process, and the tools available to researchers for handling large spectroscopic data sets are limited. Fundamental mathematical tools, such as MATLAB, Octave, and SciPy, are extremely powerful but require that the data be stored in fast memory. This memory limitation becomes impractical for even modestly sized histological images, which can be hundreds of gigabytes in size. In this paper, we propose an open-source toolkit designed to perform out-of-core processing of hyperspectral images. By taking advantage of graphical processing unit (GPU) computing combined with adaptive data streaming, our software alleviates common workstation memory limitations while achieving better performance than existing applications.

Evaluation of Aluminum Participation in the Development of Reactive Waves in Shock Compressed HMX

NASA Astrophysics Data System (ADS)

Pahl, R. J.; Trott, W. M.; Snedigar, S.; Castañeda, J. N.

2006-07-01

A series of gas gun tests has been performed to examine contributions to energy release from micron-sized and nanometric aluminum powder added to sieved (212-300μm) HMX. In the absence of added metal, 4-mm-thick, low-density (64-68% of theoretical maximum density) pressings of the sieved HMX respond to modest shock loading by developing distinctive reactive waves that exhibit both temporal and mesoscale spatial fluctuations. Parallel tests have been performed on samples containing 10% (by mass) aluminum in two particle sizes: 2-μm and 123-nm mean particle diameter, respectively. The finely dispersed aluminum initially suppresses wave growth from HMX reactions; however, after a visible induction period, the added metal drives rapid increases in the transmitted wave particle velocity. Wave profile variations as a function of the aluminum particle diameter are discussed.

Maternal cigarette smoking during pregnancy and criminal/deviant behavior: a meta-analysis.

PubMed

Pratt, Travis C; McGloin, Jean Marie; Fearn, Noelle E

2006-12-01

A growing body of empirical literature has emerged examining the somewhat inconsistent relationship between maternal cigarette smoking (MCS) during pregnancy and children's subsequent antisocial behavior. To systematically assess what existing studies reveal regarding MCS as a criminogenic risk factor for offspring, the authors subjected this body of literature to a meta-analysis. The analysis reveals a statistically significant--yet rather small--overall mean "effect size" of the relationship between MCS and the likelihood children will engage in deviant/criminal behavior. In addition to being rather moderate in size, the MCS-crime/deviance relationship is sensitive to a number of methodological specifications across empirical studies--particularly those associated with sample characteristics. The implications of this modest, and somewhat unstable, relationship are discussed in terms of guidelines for future research on this subject and how existing theoretical perspectives may be integrated to explain the MCS-crime/deviance link.

Inequalities in body size among mermithid nematodes parasitizing earwigs.

PubMed

Maure, Fanny; Poulin, Robert

2016-12-01

Variation among body sizes of adult parasitic worms determines the relative genetic contribution of individuals to the next generation as it affects the effective parasite population size. Here, we investigate inequalities in body size and how they are affected by intensity of infection in Mermis nigrescens (Mermithidae: Nematoda) parasitizing the European earwig Forficula auricularia in New Zealand. Among a population of pre-adult worms prior to their emergence from the host, we observed only modest inequalities in body length; however, among worms sharing the same individual host, inequalities in body sizes decreased with increasing intensity of infection. Thus, the more worms occurred in a host, the more the second-longest, third-longest and even fourth-longest worms approached the longest worm in body length. This pattern, also known from another mermithid species, suggests that worms sharing the same host may have infected it roughly simultaneously, when the host encountered a clump of eggs in the environment. Thus, the life history and mode of infection of the parasite may explain the modest inequalities in the sizes achieved by pre-adult worms, which are lower than those reported for endoparasitic helminths of vertebrates.

Narcissistic Personality Disorder and suicidal behavior in mood disorders.

PubMed

Coleman, Daniel; Lawrence, Ryan; Parekh, Amrita; Galfalvy, Hanga; Blasco-Fontecilla, Hilario; Brent, David A; Mann, J John; Baca-Garcia, Enrique; Oquendo, Maria A

2017-02-01

The relationship of Narcissistic Personality Disorder (NPD) to suicidal behavior is understudied. The modest body of existing research suggests that NPD is protective against low-lethality suicide attempts, but is associated with high lethality attempts. Mood-disordered patients (N = 657) received structured interviews including Axis I and II diagnosis and standardized clinical measures. Following chi-square and t-tests, a logistical regression model was constructed to identify predictors of suicide attempt. While there was no bivariate relationship of NPD on suicide attempt, in the logistic regression patients with NPD were 2.4 times less likely to make a suicide attempt (OR = 0.41; 95% CI = 0.19 - 0.88; p < 0.05), compared with non-NPD patients and controlling for possible confounding variables. NPD was not associated with attempt lethality. NPD patients were more likely to be male, to have a substance use disorder, and to have high aggression and hostility scores. Limitations include that the sample consists of only mood-disordered patients, a modest sample size of NPD, and the data are cross-sectional. The multivariate protective effect of NPD on suicide attempt is consistent with most previous research. The lower impulsivity of NPD patients and less severe personality pathology relative to other personality disorders may contribute to this effect. No relationship of NPD to attempt lethality was found, contradicting other research, but perhaps reflecting differences between study samples. Future studies should oversample NPD patients and include suicide death as an outcome. Clinical implications include discussion of individualized suicide risk assessment with NPD patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

Somatic Experiencing® Informed Therapeutic Group for the Care and Treatment of Biopsychosocial Effects upon a Gender Diverse Identity.

PubMed

Briggs, Paul C; Hayes, Sage; Changaris, Michael

2018-01-01

Somatic Experiencing ® (SE™) is a resiliency-based treatment for autonomic nervous systems dysregulation syndromes, such as posttraumatic stress disorder, anxiety, depression, and physical syndromes like chronic pain, migraines, and fibromyalgia. "Transgender/gender non-conforming/gender variant" describes people whose gender identity/expression is different, at least part of the time, from the sex assigned at birth. Research indicates transgender individuals have a higher incidence of depression, anxiety, victimization, and discrimination. SE™ tools may support transgender/gender non-conforming individuals to increase resilience in the face of discrimination and social injustice. This study is a pretest posttest within group ( N  = 7) pilot study assessing the impact of a 10 session SE™ based group treatment on depression (PHQ-9), anxiety (GAD-7), somatic symptoms (PHQ-15), quality of life (QoL) (WHOQoL-BREF), and coping with discrimination (CDS) for a cohort of seven individuals identifying as transgender/gender non-conforming. Materials were created in collaboration with members of the LGBTQIA community. Care was taken to be inclusive of gender non-conforming identities and culturally responsive in design. Participants described their gender identities as: non-binary, female to male, male to female, and gender fluid. Participants had significant increase in psychological QoL (psychological well-being) (WHOQoL-BREF) p  = 0.004, SD = 2.31, with a modest effect size of d  = 0.71. Some likely impacts of historical effect discussed. No other clinical or QoL outcomes were statistically significant. However, one outlier was identified in the dataset. When this outlier was excluded there was a trend toward significant reduction in depression symptoms (PhQ-9) p  = 0.097, SD = 3.31 and a modest effect size of d  = 0.68; somatic symptoms (PhQ-15) p  = 0.093, SD = 3.52 and a modest effect size of d  = 0.72. These data indicate that a brief 10 session intervention of SE™ could have a meaningful impact on symptoms of depression, somatization, and QoL for gender non-conforming individuals. Further research is warranted. First, this study has a small sample size limiting statistical power and generalizability. Second is a history effect. Less than 1 week prior to final data collection, there was a significant hate-motivated act in Florida targeting the LGBTQIA community.

Base Deficit and Alveolar-Arterial Gradient During Resuscitation Contribute Independently But Modestly to the Prediction of Mortality After Burn Injury

DTIC Science & Technology

2006-06-01

Base Deficit and Alveolar–Arterial Gradient During Resuscitation Contribute Independently But Modestly to the Prediction of Mortality After Burn...alveolar-arterial gradient (AaDO2), AGE, % burn, full-thickness burn size, INHAL, and with decreased pH and base excess. LRA of % burn, AGE, INHAL, and...not BE predicted earlier death in those who died. Measured during resuscitation, metabolic acidosis (ie, a base deficit) and oxygenation failure (ie

Evaluating biomarkers for prognostic enrichment of clinical trials.

PubMed

Kerr, Kathleen F; Roth, Jeremy; Zhu, Kehao; Thiessen-Philbrook, Heather; Meisner, Allison; Wilson, Francis Perry; Coca, Steven; Parikh, Chirag R

2017-12-01

A potential use of biomarkers is to assist in prognostic enrichment of clinical trials, where only patients at relatively higher risk for an outcome of interest are eligible for the trial. We investigated methods for evaluating biomarkers for prognostic enrichment. We identified five key considerations when considering a biomarker and a screening threshold for prognostic enrichment: (1) clinical trial sample size, (2) calendar time to enroll the trial, (3) total patient screening costs and the total per-patient trial costs, (4) generalizability of trial results, and (5) ethical evaluation of trial eligibility criteria. Items (1)-(3) are amenable to quantitative analysis. We developed the Biomarker Prognostic Enrichment Tool for evaluating biomarkers for prognostic enrichment at varying levels of screening stringency. We demonstrate that both modestly prognostic and strongly prognostic biomarkers can improve trial metrics using Biomarker Prognostic Enrichment Tool. Biomarker Prognostic Enrichment Tool is available as a webtool at http://prognosticenrichment.com and as a package for the R statistical computing platform. In some clinical settings, even biomarkers with modest prognostic performance can be useful for prognostic enrichment. In addition to the quantitative analysis provided by Biomarker Prognostic Enrichment Tool, investigators must consider the generalizability of trial results and evaluate the ethics of trial eligibility criteria.

7 CFR 3575.25 - Ineligible loan purposes.

Code of Federal Regulations, 2010 CFR

2010-01-01

... over tenants and services offered except for industrial-site infrastructure development, (b) Facilities... facilities, (d) Telephone systems, (e) Facilities which are not modest in size, design, and cost, (f) Finder...

Longitudinal trends in hedonic hunger after Roux-en-Y gastric bypass in adolescents.

PubMed

Cushing, Christopher C; Benoit, Stephen C; Peugh, James L; Reiter-Purtill, Jennifer; Inge, Thomas H; Zeller, Meg H

2014-01-01

Initial outcome studies have reported that Roux-en-Y gastric bypass (RYGB) is safe and efficacious for adolescents with extreme obesity. Although rapid weight loss is seen initially, data also show that modest weight regain typically occurs as early as the second postoperative year. The contribution of various psychological factors, including hedonic hunger, to postoperative weight regain has not previously been studied in adolescents. The objective of this study was to examine the variability in hedonic hunger and body mass index (BMI) over the initial 2-year period of weight loss and modest weight regain in adolescent RYGB recipients. A total of 16 adolescents completed the Power of Food Scale before surgery and at 3, 6, 12, 18, and 24 months postoperatively. Height and weight were measured at each time point, from which BMI was calculated. Nonlinear trends were observed for time on both overall hedonic hunger and hedonic hunger specifically related to food available in the adolescent's environment. The BMI reduction during the first 18 months postoperatively was paralleled by reduction in hedonic hunger; increases in hedonic hunger also paralleled the modest BMI increase at 24 months. In growth analysis, significant power gains are available to models using 4 or more points of data. However, only large effect sizes that are>.85 were detectable with a sample of 16 patients. These data provide preliminary evidence that hedonic hunger is in need of further study in adolescent patients receiving RYGB both preoperatively and postoperatively. Copyright © 2014 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Sample survey methods as a quality assurance tool in a general practice immunisation audit.

PubMed

Cullen, R

1994-04-27

In a multidoctor family practice there are often just too many sets of patients records to make it practical to repeat an audit by census of even an age band of the practice on a regular basis. This paper attempts to demonstrate how sample survey methodology can be incorporated into the quality assurance cycle. A simple random sample (with replacement) of 120 from 580 children with permanent records who were aged between 6 weeks and 2 years old from an Auckland general practice was performed, with sample size selected to give a predetermined precision. The survey was then repeated after 4 weeks. Both surveys were able to be completed within the course of a normal working day. An unexpectedly low level of under 2 years olds that were recorded as not overdue for any immunisations was found (22.5%) with only a modest improvement after a standard telephone/letter catch up campaign. Seventy-two percent of the sample held a group one community services card. The advantages of properly conducted sample surveys in producing useful estimates of known precision without disrupting office routines excessively were demonstrated. Through some attention to methodology, the trauma of a practice census can be avoided.

Previous Estimates of Mitochondrial DNA Mutation Level Variance Did Not Account for Sampling Error: Comparing the mtDNA Genetic Bottleneck in Mice and Humans

PubMed Central

Wonnapinij, Passorn; Chinnery, Patrick F.; Samuels, David C.

2010-01-01

In cases of inherited pathogenic mitochondrial DNA (mtDNA) mutations, a mother and her offspring generally have large and seemingly random differences in the amount of mutated mtDNA that they carry. Comparisons of measured mtDNA mutation level variance values have become an important issue in determining the mechanisms that cause these large random shifts in mutation level. These variance measurements have been made with samples of quite modest size, which should be a source of concern because higher-order statistics, such as variance, are poorly estimated from small sample sizes. We have developed an analysis of the standard error of variance from a sample of size n, and we have defined error bars for variance measurements based on this standard error. We calculate variance error bars for several published sets of measurements of mtDNA mutation level variance and show how the addition of the error bars alters the interpretation of these experimental results. We compare variance measurements from human clinical data and from mouse models and show that the mutation level variance is clearly higher in the human data than it is in the mouse models at both the primary oocyte and offspring stages of inheritance. We discuss how the standard error of variance can be used in the design of experiments measuring mtDNA mutation level variance. Our results show that variance measurements based on fewer than 20 measurements are generally unreliable and ideally more than 50 measurements are required to reliably compare variances with less than a 2-fold difference. PMID:20362273

Air-Sea exchange of biogenic volatile organic compounds and the impact on aerosol particle size distributions

NASA Astrophysics Data System (ADS)

Kim, Michelle J.; Novak, Gordon A.; Zoerb, Matthew C.; Yang, Mingxi; Blomquist, Byron W.; Huebert, Barry J.; Cappa, Christopher D.; Bertram, Timothy H.

2017-04-01

We report simultaneous, underway eddy covariance measurements of the vertical flux of isoprene, total monoterpenes, and dimethyl sulfide (DMS) over the Northern Atlantic Ocean during fall. Mean isoprene and monoterpene sea-to-air vertical fluxes were significantly lower than mean DMS fluxes. While rare, intense monoterpene sea-to-air fluxes were observed, coincident with elevated monoterpene mixing ratios. A statistically significant correlation between isoprene vertical flux and short wave radiation was not observed, suggesting that photochemical processes in the surface microlayer did not enhance isoprene emissions in this study region. Calculations of secondary organic aerosol production rates (PSOA) for mean isoprene and monoterpene emission rates sampled here indicate that PSOA is on average <0.1 μg m-3 d-1. Despite modest PSOA, low particle number concentrations permit a sizable role for condensational growth of monoterpene oxidation products in altering particle size distributions and the concentration of cloud condensation nuclei during episodic monoterpene emission events from the ocean.

Accounting for heterogeneity in meta-analysis using a multiplicative model-an empirical study.

PubMed

Mawdsley, David; Higgins, Julian P T; Sutton, Alex J; Abrams, Keith R

2017-03-01

In meta-analysis, the random-effects model is often used to account for heterogeneity. The model assumes that heterogeneity has an additive effect on the variance of effect sizes. An alternative model, which assumes multiplicative heterogeneity, has been little used in the medical statistics community, but is widely used by particle physicists. In this paper, we compare the two models using a random sample of 448 meta-analyses drawn from the Cochrane Database of Systematic Reviews. In general, differences in goodness of fit are modest. The multiplicative model tends to give results that are closer to the null, with a narrower confidence interval. Both approaches make different assumptions about the outcome of the meta-analysis. In our opinion, the selection of the more appropriate model will often be guided by whether the multiplicative model's assumption of a single effect size is plausible. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A randomized trial testing the efficacy of modifications to the nutrition facts table on comprehension and use of nutrition information by adolescents and young adults in Canada.

PubMed

Hobin, E; Sacco, J; Vanderlee, L; White, C M; Zuo, F; Sheeshka, J; McVey, G; Fodor O'Brien, M; Hammond, D

2015-12-01

Given the proposed changes to nutrition labelling in Canada and the dearth of research examining comprehension and use of nutrition facts tables (NFts) by adolescents and young adults, our objective was to experimentally test the efficacy of modifications to NFts on young Canadians' ability to interpret, compare and mathematically manipulate nutrition information in NFts on prepackaged food. An online survey was conducted among 2010 Canadians aged 16 to 24 years drawn from a consumer sample. Participants were randomized to view two NFts according to one of six experimental conditions, using a between-groups 2 x 3 factorial design: serving size (current NFt vs. standardized serving-sizes across similar products) x percent daily value (% DV) (current NFt vs. "low/med/high" descriptors vs. colour coding). The survey included seven performance tasks requiring participants to interpret, compare and mathematically manipulate nutrition information on NFts. Separate modified Poisson regression models were conducted for each of the three outcomes. The ability to compare two similar products was significantly enhanced in NFt conditions that included standardized serving-sizes (p ≤ .001 for all). Adding descriptors or colour coding of % DV next to calories and nutrients on NFts significantly improved participants' ability to correctly interpret % DV information (p ≤ .001 for all). Providing both standardized serving-sizes and descriptors of % DV had a modest effect on participants' ability to mathematically manipulate nutrition information to calculate the nutrient content of multiple servings of a product (relative ratio = 1.19; 95% confidence limit: 1.04-1.37). Standardizing serving-sizes and adding interpretive % DV information on NFts improved young Canadians' comprehension and use of nutrition information. Some caution should be exercised in generalizing these findings to all Canadian youth due to the sampling issues associated with the study population. Further research is needed to replicate this study in a more heterogeneous sample in Canada and across a range of food products and categories.

Second-generation antipsychotic use in schizophrenia and associated weight gain: a critical review and meta-analysis of behavioral and pharmacologic treatments.

PubMed

Das, Chandan; Mendez, Guillermo; Jagasia, Sonal; Labbate, Lawrence A

2012-08-01

Weight gain in schizophrenia, particularly secondary to second-generation antipsychotic (SGA) use, is a common adverse effect and often is associated with significant physical and psychological morbidity. We performed a critical literature review of all controlled clinical trials for pharmacologic and/or behavioral management of SGA-induced weight gain in schizophrenia patients by searching PubMed and Google Scholar. A meta-analysis was performed to estimate and compare weight changes for various medications and behavioral interventions. Sample sizes generally were small. Clinical trials were 6 weeks to 1 year, and weight loss was modest with any treatment. Although several adjunctive pharmacologic treatments showed no weight loss, sibutramine, metformin, and topiramate showed some benefit. Amantadine and orlistat were somewhat less effective and had lower rates of tolerability. Among the behavioral therapies, nutritional counseling combined with exercise showed the most benefit. Behavioral therapies, although modest, showed the most consistent benefits compared with controls. Scheduled pharmacologic treatment to prevent weight gain or promote weight loss in schizophrenia patients on SGA therapy is limited based on current studies. Switching antipsychotic agents has not been established as a long-term solution. Additional long-term studies are required to influence clinical practice.

Oil and the world economy: some possible futures.

PubMed

Kumhof, Michael; Muir, Dirk

2014-01-13

This paper, using a six-region dynamic stochastic general equilibrium model of the world economy, assesses the output and current account implications of permanent oil supply shocks hitting the world economy. For modest-sized shocks and conventional production technologies, the effects are modest. But for larger shocks, for elasticities of substitution that decline as oil usage is reduced to a minimum, and for production functions in which oil acts as a critical enabler of technologies, output growth could drop significantly. Also, oil prices could become so high that smooth adjustment, as assumed in the model, may become very difficult.

Design and Field Procedures in the US National Comorbidity Survey Replication Adolescent Supplement (NCS-A)

PubMed Central

Kessler, Ronald C.; Avenevoli, Shelli; Costello, E. Jane; Green, Jennifer Greif; Gruber, Michael J.; Heeringa, Steven; Merikangas, Kathleen R.; Pennell, Beth-Ellen; Sampson, Nancy A.; Zaslavsky, Alan M.

2009-01-01

An overview is presented of the design and field procedures of the US National Comorbidity Survey Replication Adolescent Supplement (NCS-A), a US face-to-face household survey of the prevalence and correlates of DSM-IV mental disorders. The survey was based on a dual-frame design that included 904 adolescent residents of the households that participated in the US National Comorbidity Survey Replication (85.9% response rate) and 9,244 adolescent students selected from a nationally representative sample of 320 schools (74.7% response rate). After expositing the logic of dual-frame designs, comparisons are presented of sample and population distributions on Census socio-demographic variables and, in the school sample, school characteristics. These document only minor differences between the samples and the population. The results of statistical analysis of the bias-efficiency trade-off in weight trimming are then presented. These show that modest trimming meaningfully reduces mean squared error. Analysis of comparative sample efficiency shows that the household sample is more efficient than the school sample, leading to the household sample getting a higher weight relative to its size in the consolidated sample relative to the school sample. Taken together, these results show that the NCS-A is an efficient sample of the target population with good representativeness on a range of socio-demographic and geographic variables. PMID:19507169

Neurosensory Deficits Vary as a Function of Point of Care in Pediatric Mild Traumatic Brain Injury.

PubMed

Mayer, Andrew R; Wertz, Christopher; Ryman, Sephira G; Storey, Eileen P; Park, Grace; Phillips, John; Dodd, Andrew B; Oglesbee, Scott; Campbell, Richard; Yeo, Ronald A; Wasserott, Benjamin; Shaff, Nicholas A; Leddy, John J; Mannix, Rebekah; Arbogast, Kristy B; Meier, Timothy B; Grady, Matthew F; Master, Christina L

2018-05-15

Neurosensory abnormalities are frequently observed following pediatric mild traumatic brain injury (pmTBI) and may underlie the expression of several common concussion symptoms and delay recovery. Importantly, active evaluation of neurosensory functioning more closely approximates real-world (e.g., physical and academic) environments that provoke symptom worsening. The current study determined whether symptom provocation (i.e., during neurosensory examination) improved classification accuracy relative to pre-examination symptom levels and whether symptoms varied as a function of point of care. Eighty-one pmTBI were recruited from the pediatric emergency department (PED; n = 40) or outpatient concussion clinic (n = 41), along with matched (age, sex, and education) healthy controls (HC; n = 40). All participants completed a brief (∼ 12 min) standardized neurosensory examination and clinical questionnaires. The magnitude of symptom provocation upon neurosensory examination was significantly higher for concussion clinic than for PED patients. Symptom provocation significantly improved diagnostic classification accuracy relative to pre-examination symptom levels, although the magnitude of improvement was modest, and was greater in the concussion clinic. In contrast, PED patients exhibited worse performance on measures of balance, vision, and oculomotor functioning than the concussion clinic patients, with no differences observed between both samples and HC. Despite modest sample sizes, current findings suggest that point of care represents a critical but highly under-studied variable that may influence outcomes following pmTBI. Studies that rely on recruitment from a single point of care may not generalize to the entire pmTBI population in terms of how neurosensory deficits affect recovery.

Specificity of abnormal brain volume in major depressive disorder: a comparison with borderline personality disorder.

PubMed

Depping, Malte S; Wolf, Nadine D; Vasic, Nenad; Sambataro, Fabio; Thomann, Philipp A; Christian Wolf, R

2015-03-15

Abnormal brain volume has been frequently demonstrated in major depressive disorder (MDD). It is unclear if these findings are specific for MDD since aberrant brain structure is also present in disorders with depressive comorbidity and affective dysregulation, such as borderline personality disorder (BPD). In this transdiagnostic study, we aimed to investigate if regional brain volume loss differentiates between MDD and BPD. Further, we tested for associations between brain volume and clinical variables within and between diagnostic groups. 22 Females with a DSM-IV diagnosis of MDD, 17 females with a DSM-IV diagnosis of BPD and without comorbid posttraumatic stress disorder, and 22 age-matched female healthy controls (HC) were investigated using magnetic resonance imaging. High-resolution structural data were analyzed using voxel-based morphometry. A significant (p<0.05, cluster-corrected) volume decrease of the anterior cingulate cortex (ACC) was found in MDD compared to HC, as opposed to volume decreases of the amygdala in BPD compared to both HC and MDD. Sensitivity and specificity of regional gray matter volume for a diagnosis of MDD were modest to fair. Amygdala volume was related to depressive symptoms across the entire patient sample. Potential limitations of this study include the modest sample size and the heterogeneous psychotropic drug treatment. ACC volume reduction is more pronounced in MDD with an intermediate degree of volume loss in BPD compared to HC. In contrast, amygdala volume loss is more pronounced in BPD compared to MDD, yet amygdala volume is associated with affective symptom expression in both disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

Biopsy forceps is inadequate for the resection of diminutive polyps.

PubMed

Efthymiou, M; Taylor, A C; Desmond, P V; Allen, P B; Chen, R Y

2011-04-01

Cold biopsy forceps polypectomy (CBP) is often used for the removal of diminutive polyps. The efficacy of the technique has not been thoroughly assessed. The aim of this study was to prospectively assess the efficacy of CBP for removing diminutive polyps. This was a prospective study from St Vincent's Hospital, a tertiary referral hospital in Melbourne, Australia. A total of 143 patients were screened and 52 patients with ≥ 1 diminutive polyps were enrolled. CBP was used to resect diminutive polyps until no polyp tissue was visible. The polyp base was then resected using endoscopic mucosal resection (EMR) with a 1 - 2-mm margin. The CBP and EMR samples were compared to assess completeness of the resection. Overall 39 % (21 / 54) of diminutive polyps were completely resected using CBP. After binary logistic regression analysis, polyp histology was found to be predictive of resection, with complete resection of 62 % (13 / 21) for adenomas and 24 % (8 / 33) for hyperplastic polyps (odds ratio 5.1; P = 0.008). The size and number of bites taken with the forceps were not predictive of complete response. Within the limitations of a modest sample size, CBP appears to be inadequate treatment for the removal of diminutive polyps. © Georg Thieme Verlag KG Stuttgart · New York.

Development of candidate reference materials for the measurement of lead in bone

PubMed Central

Hetter, Katherine M.; Bellis, David J.; Geraghty, Ciaran; Todd, Andrew C.; Parsons, Patrick J.

2010-01-01

The production of modest quantities of candidate bone lead (Pb) reference materials is described, and an optimized production procedure is presented. The reference materials were developed to enable an assessment of the interlaboratory agreement of laboratories measuring Pb in bone; method validation; and for calibration of solid sampling techniques such as laser ablation ICP-MS. Long bones obtained from Pb-dosed and undosed animals were selected to produce four different pools of a candidate powdered bone reference material. The Pb concentrations of these pools reflect both environmental and occupational exposure levels in humans. The animal bones were harvested post mortem, cleaned, defatted, and broken into pieces using the brittle fracture technique at liquid nitrogen temperature. The bone pieces were then ground in a knife mill to produce fragments of 2-mm size. These were further ground in an ultra-centrifugal mill, resulting in finely powdered bone material that was homogenized and then sampled-scooped into vials. Testing for contamination and homogeneity was performed via instrumental methods of analysis. PMID:18421443

Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell

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

Kriesel, Jason M.; Makarem, Camille N.; Phillips, Mark C.

We describe a versatile mid-infrared (Mid-IR) spectroscopy system developed to measure the concentration of a wide range of gases with an ultra-low sample size. The system combines a rapidly-swept external cavity quantum cascade laser (ECQCL) with a hollow fiber gas cell. The ECQCL has sufficient spectral resolution and reproducibility to measure gases with narrow features (e.g., water, methane, ammonia, etc.), and also the spectral tuning range needed to measure volatile organic compounds (VOCs), (e.g., aldehydes, ketones, hydrocarbons), sulfur compounds, chlorine compounds, etc. The hollow fiber is a capillary tube having an internal reflective coating optimized for transmitting the Mid-IR lasermore » beam to a detector. Sample gas introduced into the fiber (e.g., internal volume = 0.6 ml) interacts strongly with the laser beam, and despite relatively modest path lengths (e.g., L ~ 3 m), the requisite quantity of sample needed for sensitive measurements can be significantly less than what is required using conventional IR laser spectroscopy systems. Example measurements are presented including quantification of VOCs relevant for human breath analysis with a sensitivity of ~2 picomoles at a 1 Hz data rate.« less

Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell

NASA Astrophysics Data System (ADS)

Kriesel, Jason M.; Makarem, Camille N.; Phillips, Mark C.; Moran, James J.; Coleman, Max L.; Christensen, Lance E.; Kelly, James F.

2017-05-01

We describe a versatile mid-infrared (Mid-IR) spectroscopy system developed to measure the concentration of a wide range of gases with an ultra-low sample size. The system combines a rapidly-swept external cavity quantum cascade laser (ECQCL) with a hollow fiber gas cell. The ECQCL has sufficient spectral resolution and reproducibility to measure gases with narrow features (e.g., water, methane, ammonia, etc.), and also the spectral tuning range needed to measure volatile organic compounds (VOCs), (e.g., aldehydes, ketones, hydrocarbons), sulfur compounds, chlorine compounds, etc. The hollow fiber is a capillary tube having an internal reflective coating optimized for transmitting the Mid-IR laser beam to a detector. Sample gas introduced into the fiber (e.g., internal volume = 0.6 ml) interacts strongly with the laser beam, and despite relatively modest path lengths (e.g., L 3 m), the requisite quantity of sample needed for sensitive measurements can be significantly less than what is required using conventional IR laser spectroscopy systems. Example measurements are presented including quantification of VOCs relevant for human breath analysis with a sensitivity of 2 picomoles at a 1 Hz data rate.

Sample size and classification error for Bayesian change-point models with unlabelled sub-groups and incomplete follow-up.

PubMed

White, Simon R; Muniz-Terrera, Graciela; Matthews, Fiona E

2018-05-01

Many medical (and ecological) processes involve the change of shape, whereby one trajectory changes into another trajectory at a specific time point. There has been little investigation into the study design needed to investigate these models. We consider the class of fixed effect change-point models with an underlying shape comprised two joined linear segments, also known as broken-stick models. We extend this model to include two sub-groups with different trajectories at the change-point, a change and no change class, and also include a missingness model to account for individuals with incomplete follow-up. Through a simulation study, we consider the relationship of sample size to the estimates of the underlying shape, the existence of a change-point, and the classification-error of sub-group labels. We use a Bayesian framework to account for the missing labels, and the analysis of each simulation is performed using standard Markov chain Monte Carlo techniques. Our simulation study is inspired by cognitive decline as measured by the Mini-Mental State Examination, where our extended model is appropriate due to the commonly observed mixture of individuals within studies who do or do not exhibit accelerated decline. We find that even for studies of modest size ( n = 500, with 50 individuals observed past the change-point) in the fixed effect setting, a change-point can be detected and reliably estimated across a range of observation-errors.

Crystallite-size dependency of the pressure and temperature response in nanoparticles of magnesia

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

Rodenbough, Philip P.; Chan, Siu-Wai

We have carefully measured the hydrostatic compressibility and thermal expansion for a series of magnesia nanoparticles. We found a strong variance in these mechanical properties as crystallite size changed. For decreasing crystallite sizes, bulk modulus first increased, then reached a modest maximum of 165 GPa at an intermediate crystallite size of 14 nm, and then decreased thereafter to 77 GPa at 9 nm. Thermal expansion, meanwhile, decreased continuously to 70% of bulk value at 9 nm. These results are consistent to nano-ceria and together provide important insights into the thermal-mechanical structural properties of oxide nanoparticles.

Imaging inert fluorinated gases in cracks: perhaps in David's ankles.

PubMed

Kuethe, Dean O; Scholz, Markus D; Fantazzini, Paola

2007-05-01

Inspired by the challenge of determining the nature of cracks on the ankles of Michelangelo's statue David, we discovered that one can image SF(6) gas in cracks in marble samples with alacrity. The imaging method produces images of gas with a signal-to-noise ratio (SNR) of 100-250, which is very high for magnetic resonance imaging (MRI) in general, let alone for an image of a gas at thermal equilibrium polarization. To put this unusual SNR in better perspective, we imaged SF(6) in a crack in a marble sample and imaged the lung tissue of a live rat (a more familiar variety of sample to many MRI scientists) using the same pulse sequence, the same size coils and the same MRI system. In both cases, we try to image subvoxel thin sheets of material that should appear bright against a darker background. By choosing imaging parameters appropriate for the different relaxation properties of SF(6) gas versus lung tissue and by choosing voxel sizes appropriate for the different goals of detecting subvoxel cracks on marble versus resolving subvoxel thin sheets of tissue, the SNR for voxels full of material was 220 and 14 for marble and lung, respectively. A major factor is that we chose large voxels to optimize SNR for detecting small cracks and we chose small voxels for resolving lung features at the expense of SNR. Imaging physics will cooperate to provide detection of small cracks on marble, but David's size poses a challenge for magnet designers. For the modest goal of imaging cracks in the left ankle, we desire a magnet with an approximately 32-cm gap and a flux density of approximately 0.36 T that weighs <500 kg.

Candidate genes for aggression and antisocial behavior: a meta-analysis of association studies of the 5HTTLPR and MAOA-uVNTR.

PubMed

Ficks, Courtney A; Waldman, Irwin D

2014-09-01

Variation in central serotonin levels due to genetic mutations or experimental modifications has been associated with the manifestation of aggression in humans and animals. Many studies have examined whether common variants in serotonergic genes are implicated in aggressive or antisocial behaviors (ASB) in human samples. The two most commonly studied polymorphisms have been the serotonin transporter linked polymorphic region of the serotonin transporter gene (5HTTLPR) and the 30 base pair variable number of tandem repeats of the monoamine oxidase A gene (MAOA-uVNTR). Despite the aforementioned theoretical justification for these polymorphisms, findings across studies have been mixed and are thus difficult to interpret. A meta-analysis of associations of the 5HTTLPR and MAOA-uVNTR with ASB was conducted to determine: (1) the overall magnitude of effects for each polymorphism, (2) the extent of heterogeneity in effect sizes across studies and the likelihood of publication bias, and (3) whether sample-level or study-level characteristics could explain observed heterogeneity across studies. Both the 5HTTLPR and the MAOA-uVNTR were significantly associated with ASB across studies. There was also significant and substantial heterogeneity in the effect sizes for both markers, but this heterogeneity was not explained by any sample-level or study-level characteristics examined. We did not find any evidence for publication bias across studies for the MAOA-uVNTR, but there was evidence for an oversampling of statistically significant effect sizes for the 5HTTLPR. These findings provide support for the modest role of common serotonergic variants in ASB. Implications regarding the role of serotonin in antisocial behavior and the conceptualization of antisocial and aggressive phenotypes are discussed.

Effect of Elevated Reperfusion Pressure on "No Reflow" Area and Infarct Size in a Porcine Model of Ischemia-Reperfusion.

PubMed

Pantsios, Chris; Kapelios, Chris; Vakrou, Styliani; Diakos, Nikolaos; Pozios, Iraklis; Kontogiannis, Chris; Nanas, John; Malliaras, Konstantinos

2016-07-01

The "no reflow" phenomenon (microvascular obstruction despite restoration of epicardial blood flow) develops postreperfusion in acute myocardial infarction and is associated with poor prognosis. We hypothesized that increased reperfusion pressure may attenuate the no reflow phenomenon, as it could provide adequate flow to overcome the high resistance of the microvasculature within the no reflow zone. Thus, we investigated the effect of modestly elevated blood pressure during reperfusion on the extent of no reflow area and infarct size in a porcine model of ischemia-reperfusion. Eighteen farm pigs underwent acute myocardial infarction by occlusion of the anterior descending coronary artery for 1 hour, followed by 2 hours of reperfusion. Just prior to reperfusion, animals were randomized into 2 groups: in group 1 (control group, n = 9), no intervention was performed. In group 2 (n = 9), aortic pressure was increased by ∼20% (compared to ischemia) by partial clamping of the ascending aorta during reperfusion. Following 2 hours of reperfusion, animals were euthanized to measure area at risk, infarct size, and area of no reflow. Partial clamping of the ascending aorta resulted in modest elevation of blood pressure during reperfusion. The area at risk did not differ between the 2 groups. The no reflow area was significantly increased in group 2 compared to control animals (50% ± 13% vs 37% ± 9% of the area at risk; P = .04). The infarcted area was significantly increased in group 2 compared to control animals (75% ± 17% vs 52% ± 23% of the area at risk; P = .03). Significant positive correlations were observed between systolic aortic pressure and no reflow area, between systolic aortic pressure and infarcted area and between infarcted area and no reflow area during reperfusion. Modestly elevated blood pressure during reperfusion is associated with an increase in no reflow area and in infarct size in a clinically relevant porcine model of ischemia-reperfusion. © The Author(s) 2015.

EXACT DISTRIBUTIONS OF INTRACLASS CORRELATION AND CRONBACH'S ALPHA WITH GAUSSIAN DATA AND GENERAL COVARIANCE.

PubMed

Kistner, Emily O; Muller, Keith E

2004-09-01

Intraclass correlation and Cronbach's alpha are widely used to describe reliability of tests and measurements. Even with Gaussian data, exact distributions are known only for compound symmetric covariance (equal variances and equal correlations). Recently, large sample Gaussian approximations were derived for the distribution functions. New exact results allow calculating the exact distribution function and other properties of intraclass correlation and Cronbach's alpha, for Gaussian data with any covariance pattern, not just compound symmetry. Probabilities are computed in terms of the distribution function of a weighted sum of independent chi-square random variables. New F approximations for the distribution functions of intraclass correlation and Cronbach's alpha are much simpler and faster to compute than the exact forms. Assuming the covariance matrix is known, the approximations typically provide sufficient accuracy, even with as few as ten observations. Either the exact or approximate distributions may be used to create confidence intervals around an estimate of reliability. Monte Carlo simulations led to a number of conclusions. Correctly assuming that the covariance matrix is compound symmetric leads to accurate confidence intervals, as was expected from previously known results. However, assuming and estimating a general covariance matrix produces somewhat optimistically narrow confidence intervals with 10 observations. Increasing sample size to 100 gives essentially unbiased coverage. Incorrectly assuming compound symmetry leads to pessimistically large confidence intervals, with pessimism increasing with sample size. In contrast, incorrectly assuming general covariance introduces only a modest optimistic bias in small samples. Hence the new methods seem preferable for creating confidence intervals, except when compound symmetry definitely holds.

Negligible impact of rare autoimmune-locus coding-region variants on missing heritability.

PubMed

Hunt, Karen A; Mistry, Vanisha; Bockett, Nicholas A; Ahmad, Tariq; Ban, Maria; Barker, Jonathan N; Barrett, Jeffrey C; Blackburn, Hannah; Brand, Oliver; Burren, Oliver; Capon, Francesca; Compston, Alastair; Gough, Stephen C L; Jostins, Luke; Kong, Yong; Lee, James C; Lek, Monkol; MacArthur, Daniel G; Mansfield, John C; Mathew, Christopher G; Mein, Charles A; Mirza, Muddassar; Nutland, Sarah; Onengut-Gumuscu, Suna; Papouli, Efterpi; Parkes, Miles; Rich, Stephen S; Sawcer, Steven; Satsangi, Jack; Simmonds, Matthew J; Trembath, Richard C; Walker, Neil M; Wozniak, Eva; Todd, John A; Simpson, Michael A; Plagnol, Vincent; van Heel, David A

2013-06-13

Genome-wide association studies (GWAS) have identified common variants of modest-effect size at hundreds of loci for common autoimmune diseases; however, a substantial fraction of heritability remains unexplained, to which rare variants may contribute. To discover rare variants and test them for association with a phenotype, most studies re-sequence a small initial sample size and then genotype the discovered variants in a larger sample set. This approach fails to analyse a large fraction of the rare variants present in the entire sample set. Here we perform simultaneous amplicon-sequencing-based variant discovery and genotyping for coding exons of 25 GWAS risk genes in 41,911 UK residents of white European origin, comprising 24,892 subjects with six autoimmune disease phenotypes and 17,019 controls, and show that rare coding-region variants at known loci have a negligible role in common autoimmune disease susceptibility. These results do not support the rare-variant synthetic genome-wide-association hypothesis (in which unobserved rare causal variants lead to association detected at common tag variants). Many known autoimmune disease risk loci contain multiple, independently associated, common and low-frequency variants, and so genes at these loci are a priori stronger candidates for harbouring rare coding-region variants than other genes. Our data indicate that the missing heritability for common autoimmune diseases may not be attributable to the rare coding-region variant portion of the allelic spectrum, but perhaps, as others have proposed, may be a result of many common-variant loci of weak effect.

Technetium-99 and strontium-90: Abundance determination at ultratrace sensitivity by AMS as signatures of undeclared nuclear reprocessing activity

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

McAninch, J.E.; Proctor, I.D.

1995-03-01

The purpose of this White Paper is to examine the use of the ultratrace technique Accelerator Mass Spectrometry (AMS) to lower detection limits for {sup 99}Tc and {sup 90}Sr, and to examine the utility of these isotopes as signatures of a convert reprocessing facility. The International Atomic Energy Agency (IAEA) has committed to improving the effectiveness of the IAEA Safeguards System. This is in some degree a result of the discovery in 1991 of an undeclared Iraqi EMIS program. Recommendations from the March 1993 Consultants Group Meeting have resulted in several studies and follow on field trials to identify environmentalmore » signatures from covert nuclear fuel reprocessing activity. In particular, the April, 1993 reports of the Standing Advisory Group on Safeguards Implementation (SAGSI) identified the long-lived radioisotopes Technetium-99 and strontium-90 as two reliable signatures of fuel reprocessing activity. This report also suggested pathways in the chemical processing of irradiated fuel where these elements would be volatilized and potentially released in amounts detectable with ultratrace sensitivity techniques. Based on measured {sup 99}Tc background levels compiled from a variety of sources, it is estimated that AMS can provide 10% measurements of environmental levels of {sup 99}Tc in a few minutes using modestly sized samples: a few grams for soils, plants, or animal tissues; one to several liters for rain or seawater samples; and tens to hundreds of cubic meters for air sampling. Small sample sizes and high sample throughput result in significant increases in feasibility, cost effectiveness, and quality of data for a regional monitoring program. Similar results are expected for {sup 90}Sr.« less

Why do shape aftereffects increase with eccentricity?

PubMed

Gheorghiu, Elena; Kingdom, Frederick A A; Bell, Jason; Gurnsey, Rick

2011-12-20

Studies have shown that spatial aftereffects increase with eccentricity. Here, we demonstrate that the shape-frequency and shape-amplitude aftereffects, which describe the perceived shifts in the shape of a sinusoidal-shaped contour following adaptation to a slightly different sinusoidal-shaped contour, also increase with eccentricity. Why does this happen? We first demonstrate that the perceptual shift increases with eccentricity for stimuli of fixed sizes. These shifts are not attenuated by variations in stimulus size; in fact, at each eccentricity the degree of perceptual shift is scale-independent. This scale independence is specific to the aftereffect because basic discrimination thresholds (in the absence of adaptation) decrease as size increases. Structural aspects of the displays were found to have a modest effect on the degree of perceptual shift; the degree of adaptation depends modestly on distance between stimuli during adaptation and post-adaptation testing. There were similar temporal rates of decline of adaptation across the visual field and higher post-adaptation discrimination thresholds in the periphery than in the center. The observed results are consistent with greater sensitivity reduction in adapted mechanisms following adaptation in the periphery or an eccentricity-dependent increase in the bandwidth of the shape-frequency- and shape-amplitude-selective mechanisms.

Body Size Estimation from Early to Middle Childhood: Stability of Underestimation, BMI, and Gender Effects.

PubMed

Steinsbekk, Silje; Klöckner, Christian A; Fildes, Alison; Kristoffersen, Pernille; Rognsås, Stine L; Wichstrøm, Lars

2017-01-01

Individuals who are overweight are more likely to underestimate their body size than those who are normal weight, and overweight underestimators are less likely to engage in weight loss efforts. Underestimation of body size might represent a barrier to prevention and treatment of overweight; thus insight in how underestimation of body size develops and tracks through the childhood years is needed. The aim of the present study was therefore to examine stability in children's underestimation of body size, exploring predictors of underestimation over time. The prospective path from underestimation to BMI was also tested. In a Norwegian cohort of 6 year olds, followed up at ages 8 and 10 (analysis sample: n = 793) body size estimation was captured by the Children's Body Image Scale, height and weight were measured and BMI calculated. Overall, children were more likely to underestimate than overestimate their body size. Individual stability in underestimation was modest, but significant. Higher BMI predicted future underestimation, even when previous underestimation was adjusted for, but there was no evidence for the opposite direction of influence. Boys were more likely than girls to underestimate their body size at ages 8 and 10 (age 8: 38.0% vs. 24.1%; Age 10: 57.9% vs. 30.8%) and showed a steeper increase in underestimation with age compared to girls. In conclusion, the majority of 6, 8, and 10-year olds correctly estimate their body size (prevalence ranging from 40 to 70% depending on age and gender), although a substantial portion perceived themselves to be thinner than they actually were. Higher BMI forecasted future underestimation, but underestimation did not increase the risk for excessive weight gain in middle childhood.

On Ambiguities in SAR Design

NASA Technical Reports Server (NTRS)

Freeman, Anthony

2006-01-01

Ambiguities are an aliasing effect caused by the periodic sampling of the scene backscatter inherent to pulsed radar systems such as Synthetic Aperture radar (SAR). In this paper we take a fresh look at the relationship between SAR range and azimuth ambiguity constraints on the allowable pulse repetition frequency (PRF) and the antenna length. We show that for high squint angles smaller antennas may be feasible in some cases. For some applications, the ability to form a synthetic aperture at high squint angles is desirable, but the size of the antenna causes problems in the design of systems capable of such operation. This is because the SAR system design is optimized for a side-looking geometry. In two examples design examples we take a suboptimum antenna size and examine the performance in terms of azimuth resolution and swath width as a function of squint angle. We show that for stripmap SARs, the swath width is usually worse for off-boresight squint angles, because it is severely limited by range walk, except in cases where we relax the spatial resolution. We consider the implications for the design of modest-resolution, narrow swath, scanning SAR scatterometers .

MICROLENSING OF QUASAR BROAD EMISSION LINES: CONSTRAINTS ON BROAD LINE REGION SIZE

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

Guerras, E.; Mediavilla, E.; Jimenez-Vicente, J.

2013-02-20

We measure the differential microlensing of the broad emission lines between 18 quasar image pairs in 16 gravitational lenses. We find that the broad emission lines are in general weakly microlensed. The results show, at a modest level of confidence (1.8{sigma}), that high ionization lines such as C IV are more strongly microlensed than low ionization lines such as H{beta}, indicating that the high ionization line emission regions are more compact. If we statistically model the distribution of microlensing magnifications, we obtain estimates for the broad line region size of r{sub s} = 24{sup +22} {sub -15} and r{sub s}more » = 55{sup +150} {sub -35} lt-day (90% confidence) for the high and low ionization lines, respectively. When the samples are divided into higher and lower luminosity quasars, we find that the line emission regions of more luminous quasars are larger, with a slope consistent with the expected scaling from photoionization models. Our estimates also agree well with the results from local reveberation mapping studies.« less

Making Research Cyberinfrastructure a Strategic Choice

ERIC Educational Resources Information Center

Hacker, Thomas J.; Wheeler, Bradley C.

2007-01-01

The commoditization of low-cost hardware has enabled even modest-sized laboratories and research projects to own their own "supercomputers." The authors argue that this local solution undermines rather than amplifies the research potential of scholars. CIOs, provosts, and research technologists should consider carefully an overall…

Exo-S: A Probe-scale Space Mission to Directly Image and Spectroscopically Characterize Exoplanetary Systems Using a Starshade and Telescope System

NASA Astrophysics Data System (ADS)

Seager, Sara; Cash, Webster C.; Kasdin, N. Jeremy; Sparks, William B.; Turnbull, Margaret C.; Kuchner, Marc J.; Roberge, Aki; Domagal-Goldman, Shawn; Shaklan, Stuart; Thomson, Mark; Lisman, Doug; Martin, Suzanne; Cady, Eric; Webb, David

2014-06-01

"Exo-S" is NASA's first directed community study of a starshade and telescope system for space-based discovery and characterization of exoplanets by direct imaging. Under a cost cap of $1B, Exo-S will use a modestly sized starshade (also known as an "external occulter") and a modest aperture space telescope for high contrast observations of exoplanetary systems. The Exo-S will obtain spectra of a subset of its newly discovered exoplanets as well as already known Jupiter-mass exoplanets. Exo-S will be capable of reaching down to the discovery of Earth-size planets in the habitable zones of twenty sun-like stars, with a favorable few accessible for spectral characterization. We present highlights of the science goals, the mission design, and technology milestones already reached. At the study conclusion in 2015, NASA will evaluate the Exo-S concept for potential development at the end of this decade.

Tumor shrinkage and objective response rates: gold standard for oncology efficacy screening trials, or an outdated end point?

PubMed

Bradbury, Penelope; Seymour, Lesley

2009-01-01

Phase II clinical trials have long been used to screen new cancer therapeutics for antitumor activity ("efficacy") worthy of further evaluation. Traditionally, the primary end point used in these screening trials has been objective response rate (RR), with the desired rate being arbitrarily set by the researchers before initiation of the trial. For cytotoxic agents, especially in common tumor types, response has been a reasonably robust and validated surrogate of benefit. Phase II trials with response as an end point have a modest sample size (15-40 patients) and are completed rapidly allowing early decisions regarding future development of a given agent. More recently, a number of new agents have proven successful in pivotal phase III studies, despite a low or very modest RR demonstrated in early clinical trials. Researchers have postulated that these novel agents, as a class, may not induce significant regression of tumors, and that the use of RR as an end point for phase II studies will result in false negative results, and point out that not all available data is used in making the decision. Others have pointed out that even novel agents have proven unsuccessful in pivotal trials if objective responses are not demonstrated in early clinical trials. We review here the historical and current information regarding objective tumor response.

Results of Large-Scale Spacecraft Flammability Tests

NASA Technical Reports Server (NTRS)

Ferkul, Paul; Olson, Sandra; Urban, David L.; Ruff, Gary A.; Easton, John; T'ien, James S.; Liao, Ta-Ting T.; Fernandez-Pello, A. Carlos; Torero, Jose L.; Eigenbrand, Christian;

Demographics of the gay and lesbian population in the United States: evidence from available systematic data sources.

PubMed

Black, D; Gates, G; Sanders, S; Taylor, L

2000-05-01

This work provides an overview of standard social science data sources that now allow some systematic study of the gay and lesbian population in the United States. For each data source, we consider how sexual orientation can be defined, and we note the potential sample sizes. We give special attention to the important problem of measurement error, especially the extent to which individuals recorded as gay and lesbian are indeed recorded correctly. Our concern is that because gays and lesbians constitute a relatively small fraction of the population, modest measurement problems could lead to serious errors in inference. In examining gays and lesbians in multiple data sets we also achieve a second objective: We provide a set of statistics about this population that is relevant to several current policy debates.

Exo-C: a Probe-Scale Space Mission to Directly Image and Spectroscopically Characterize Exoplanetary Systems Using an Internal Coronagraph

NASA Technical Reports Server (NTRS)

Stapelfeldt, Karl R.; Brenner, Michael P.; Warfield, Keith R.; Dekens, Frank G.; Belikov, Ruslan; Brugarolas, Paul B.; Bryden, Geoffrey; Cahoy, Kerri L.; Chakrabarti, Supriya; Dubovitsky, Serge;

In first-time mothers, post-partum depressive symptom prospectively predict symptoms of post-traumatic stress.

PubMed

Shahar, Golan; Herishanu-Gilutz, Shirley; Holcberg, Gershon; Kofman, Ora

2015-11-01

Symptoms of both depression and Post-Traumatic Stress Disorder (PTSD) are prevalent among first-time mothers following birth. However, the direction of the association between the two types of symptoms is unclear. Ninety six first-time mothers giving birth via vaginal delivery (N=38), emergency C-Section (N=27) and planned C-Section (N=21) were assessed for depression and PTSD twice: Six weeks post-partum and six-weeks later. Cross-lagged Structural Equation Modeling (SEM) analyses revealed a prospective effect of depressive symptoms on PTSD symptoms. No moderating factors were identified. A relatively modest sample size and only two assessment waves. An early detection and intervention with symptoms of post-partum depression might also prevent the development of PTSD symptoms. Copyright © 2015 Elsevier B.V. All rights reserved.

Can Genetic Analysis of Putative Blood Alzheimer’s Disease Biomarkers Lead to Identification of Susceptibility Loci?

PubMed Central

Huebinger, Ryan M.; Shewale, Shantanu J.; Koenig, Jessica L.; Mitchel, Jeffrey S.; O’Bryant, Sid E.; Waring, Stephen C.; Diaz-Arrastia, Ramon; Chasse, Scott

2015-01-01

Although 24 Alzheimer’s disease (AD) risk loci have been reliably identified, a large portion of the predicted heritability for AD remains unexplained. It is expected that additional loci of small effect will be identified with an increased sample size. However, the cost of a significant increase in Case-Control sample size is prohibitive. The current study tests whether exploring the genetic basis of endophenotypes, in this case based on putative blood biomarkers for AD, can accelerate the identification of susceptibility loci using modest sample sizes. Each endophenotype was used as the outcome variable in an independent GWAS. Endophenotypes were based on circulating concentrations of proteins that contributed significantly to a published blood-based predictive algorithm for AD. Endophenotypes included Monocyte Chemoattractant Protein 1 (MCP1), Vascular Cell Adhesion Molecule 1 (VCAM1), Pancreatic Polypeptide (PP), Beta2 Microglobulin (B2M), Factor VII (F7), Adiponectin (ADN) and Tenascin C (TN-C). Across the seven endophenotypes, 47 SNPs were associated with outcome with a p-value ≤1x10-7. Each signal was further characterized with respect to known genetic loci associated with AD. Signals for several endophenotypes were observed in the vicinity of CR1, MS4A6A/MS4A4E, PICALM, CLU, and PTK2B. The strongest signal was observed in association with Factor VII levels and was located within the F7 gene. Additional signals were observed in MAP3K13, ZNF320, ATP9B and TREM1. Conditional regression analyses suggested that the SNPs contributed to variation in protein concentration independent of AD status. The identification of two putatively novel AD loci (in the Factor VII and ATP9B genes), which have not been located in previous studies despite massive sample sizes, highlights the benefits of an endophenotypic approach for resolving the genetic basis for complex diseases. The coincidence of several of the endophenotypic signals with known AD loci may point to novel genetic interactions and should be further investigated. PMID:26625115

Can Genetic Analysis of Putative Blood Alzheimer's Disease Biomarkers Lead to Identification of Susceptibility Loci?

PubMed

Barber, Robert C; Phillips, Nicole R; Tilson, Jeffrey L; Huebinger, Ryan M; Shewale, Shantanu J; Koenig, Jessica L; Mitchel, Jeffrey S; O'Bryant, Sid E; Waring, Stephen C; Diaz-Arrastia, Ramon; Chasse, Scott; Wilhelmsen, Kirk C

2015-01-01

Although 24 Alzheimer's disease (AD) risk loci have been reliably identified, a large portion of the predicted heritability for AD remains unexplained. It is expected that additional loci of small effect will be identified with an increased sample size. However, the cost of a significant increase in Case-Control sample size is prohibitive. The current study tests whether exploring the genetic basis of endophenotypes, in this case based on putative blood biomarkers for AD, can accelerate the identification of susceptibility loci using modest sample sizes. Each endophenotype was used as the outcome variable in an independent GWAS. Endophenotypes were based on circulating concentrations of proteins that contributed significantly to a published blood-based predictive algorithm for AD. Endophenotypes included Monocyte Chemoattractant Protein 1 (MCP1), Vascular Cell Adhesion Molecule 1 (VCAM1), Pancreatic Polypeptide (PP), Beta2 Microglobulin (B2M), Factor VII (F7), Adiponectin (ADN) and Tenascin C (TN-C). Across the seven endophenotypes, 47 SNPs were associated with outcome with a p-value ≤1x10(-7). Each signal was further characterized with respect to known genetic loci associated with AD. Signals for several endophenotypes were observed in the vicinity of CR1, MS4A6A/MS4A4E, PICALM, CLU, and PTK2B. The strongest signal was observed in association with Factor VII levels and was located within the F7 gene. Additional signals were observed in MAP3K13, ZNF320, ATP9B and TREM1. Conditional regression analyses suggested that the SNPs contributed to variation in protein concentration independent of AD status. The identification of two putatively novel AD loci (in the Factor VII and ATP9B genes), which have not been located in previous studies despite massive sample sizes, highlights the benefits of an endophenotypic approach for resolving the genetic basis for complex diseases. The coincidence of several of the endophenotypic signals with known AD loci may point to novel genetic interactions and should be further investigated.

Spherical torus fusion reactor

DOEpatents

Peng, Yueng-Kay M.

1989-04-04

A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

Spherical torus fusion reactor

DOEpatents

Peng, Yueng-Kay M.

1989-01-01

A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

The short-term effects of merger on hospital operations.

PubMed Central

Alexander, J A; Halpern, M T; Lee, S Y

1996-01-01

OBJECTIVE: The short-term effects of merger on three areas of hospital operations - scale of activity, personnel/staffing practices, and operating efficiency - is examined. DATA SOURCES: Secondary data obtained from the AHA Annual Surveys (1980-1990) were applied to analyze 92 hospital mergers over the period 1982-1989. STUDY DESIGN: The study employed a multiple time-series design involving a six-year longitudinal assessment of change in hospital operating characteristics before and after merger, and a parallel analysis of change in a randomly selected group of nonmerging hospitals. DATA COLLECTION: Pooled, cross-sectional data files were constructed. Comparisons were evaluated using paired and two-sample t-tests. PRINCIPAL FINDINGS: General merger effects occurred primarily in areas related to operating efficiency. Merger resulted in slowing rates of preexisting trends, rather than dramatic improvements in operating practices. CONCLUSIONS: The short-term impact of merger was generally modest but differed by the conditions under which the merger occurred. Specifically, mergers occurring later in the study period and mergers between similarly sized hospitals displayed greater change in operating characteristics than those occurring earlier in the study period and those between hospitals of dissimilar size. Such differences are attributed respectively to increased competitive pressures after PPS and to greater opportunities for consolidation and efficiencies in mergers involving similarly sized hospitals. PMID:8591932

Power and instrument strength requirements for Mendelian randomization studies using multiple genetic variants.

PubMed

Pierce, Brandon L; Ahsan, Habibul; Vanderweele, Tyler J

2011-06-01

Mendelian Randomization (MR) studies assess the causality of an exposure-disease association using genetic determinants [i.e. instrumental variables (IVs)] of the exposure. Power and IV strength requirements for MR studies using multiple genetic variants have not been explored. We simulated cohort data sets consisting of a normally distributed disease trait, a normally distributed exposure, which affects this trait and a biallelic genetic variant that affects the exposure. We estimated power to detect an effect of exposure on disease for varying allele frequencies, effect sizes and samples sizes (using two-stage least squares regression on 10,000 data sets-Stage 1 is a regression of exposure on the variant. Stage 2 is a regression of disease on the fitted exposure). Similar analyses were conducted using multiple genetic variants (5, 10, 20) as independent or combined IVs. We assessed IV strength using the first-stage F statistic. Simulations of realistic scenarios indicate that MR studies will require large (n > 1000), often very large (n > 10,000), sample sizes. In many cases, so-called 'weak IV' problems arise when using multiple variants as independent IVs (even with as few as five), resulting in biased effect estimates. Combining genetic factors into fewer IVs results in modest power decreases, but alleviates weak IV problems. Ideal methods for combining genetic factors depend upon knowledge of the genetic architecture underlying the exposure. The feasibility of well-powered, unbiased MR studies will depend upon the amount of variance in the exposure that can be explained by known genetic factors and the 'strength' of the IV set derived from these genetic factors.

Hippocampus and Basal Forebrain Volumetry for Dementia and Mild Cognitive Impairment Diagnosis: Could It Be Useful in Primary Care?

PubMed

Teipel, Stefan J; Keller, Felix; Thyrian, Jochen R; Strohmaier, Urs; Altiner, Attila; Hoffmann, Wolfgang; Kilimann, Ingo

2017-01-01

Once a patient or a knowledgeable informant has noticed decline in memory or other cognitive functions, initiation of early dementia assessment is recommended. Hippocampus and cholinergic basal forebrain (BF) volumetry supports the detection of prodromal and early stages of Alzheimer's disease (AD) dementia in highly selected patient populations. To compare effect size and diagnostic accuracy of hippocampus and BF volumetry between patients recruited in highly specialized versus primary care and to assess the effect of white matter lesions as a proxy for cerebrovascular comorbidity on diagnostic accuracy. We determined hippocampus and BF volumes and white matter lesion load from MRI scans of 71 participants included in a primary care intervention trial (clinicaltrials.gov identifier: NCT01401582) and matched 71 participants stemming from a memory clinic. Samples included healthy controls and people with mild cognitive impairment (MCI), AD dementia, mixed dementia, and non-AD related dementias. Volumetric measures reached similar effect sizes and cross-validated levels of accuracy in the primary care and the memory clinic samples for the discrimination of AD and mixed dementia cases from healthy controls. In the primary care MCI cases, volumetric measures reached only random guessing levels of accuracy. White matter lesions had only a modest effect on effect size and diagnostic accuracy. Hippocampus and BF volumetry may usefully be employed for the identification of AD and mixed dementia, but the detection of MCI does not benefit from the use of these volumetric markers in a primary care setting.

Fluorescence Stability of Mercaptopropionic Acid Capped Cadmium Telluride Quantum Dots in Various Biochemical Buffers.

PubMed

Borse, Vivek; Kashikar, Adisha; Srivastava, Rohit

2018-04-01

Quantum dots are the semiconductor nanocrystals having unique optical and electronic properties. Quantum dots are category of fluorescent labels utilized for biological tagging, biosensing, bioassays, bioimaging and in vivo imaging as they exhibit very small size, signal brightness, photostability, tuning of light emission range, longer photoluminescence decay time as compared to organic dyes. In this work, we have synthesized and characterized mercaptopropionic acid capped cadmium telluride quantum dots (MPA-CdTe QDs) using hydrothermal method. The study further reports fluorescence intensity stability of quantum dots suspended in different buffers of varying concentration (1-100 mM), stored at various photophysical conditions. Fluorescence intensity values were reduced with increase in buffer concentration. When the samples were stored at room temperature in ambient light condition the quantum dots suspended in different buffers lost the fluorescence intensity after day 15 (except TRIS II). Fluorescence intensity values were found stable for more than 30 days when the samples were stored in dark condition. Samples stored in refrigerator displayed modest fluorescence intensity even after 300 days of storage. Thus, storage of MPA-CdTe QDs in refrigerator may be the suitable choice to maintain its fluorescence stability for longer time for further application.

Using video feedback to improve early father-infant interaction: a pilot study.

PubMed

Lawrence, Peter J; Davies, Beverley; Ramchandani, Paul G

2013-01-01

Preventive interventions with parents of infants have tended to focus on mothers. Recent research focused on fathers suggests that their involvement in interventions might enhance effectiveness. One effective approach with mothers is the brief, home-based Video-feedback Intervention to promote Positive Parenting (VIPP). This paper is a report of a pilot study of VIPP with fathers to assess its feasibility. Five fathers were recruited from an existing longitudinal study of parents. The primary outcome was acceptability, assessed using a semi-structured questionnaire after completion of the intervention. All fathers completed all sessions of the intervention. Fathers rated the intervention as having had a significant impact on their understanding of their child's thoughts and feelings, and as having improved their communication and relationship with their baby. Fathers' feedback was generally positive. The flexibility to conduct sessions at home (or at fathers' places of work) and the flexible timing of sessions were identified as fundamental to successful delivery. The results of this pilot study are encouraging, as VIPP with fathers was feasible. In light of the modest sample size, and the use of a non-clinical sample, the intervention must be evaluated with larger, clinical samples to evaluate its efficacy with fathers.

Transcranial Magnetic Stimulation for Obsessive-Compulsive Disorder: An Updated Systematic Review and Meta-analysis.

PubMed

Trevizol, Alisson Paulino; Shiozawa, Pedro; Cook, Ian A; Sato, Isa Albuquerque; Kaku, Caio Barbosa; Guimarães, Fernanda Bs; Sachdev, Perminder; Sarkhel, Sujit; Cordeiro, Quirino

2016-12-01

Transcranial magnetic stimulation (TMS) is a promising noninvasive brain stimulation intervention. Transcranial magnetic stimulation has been proposed for obsessive-compulsive disorder (OCD) with auspicious results. To assess the efficacy of TMS for OCD in randomized clinical trials (RCTs). Systematic review using MEDLINE and EMBASE from the first RCT available until March 11, 2016. The main outcome was the Hedges g for continuous scores for Yale-Brown Obsessive Compulsive Scale in a random-effects model. Heterogeneity was evaluated with the I and the χ test. Publication bias was evaluated using the Begg funnel plot. Metaregression was performed using the random-effects model modified by Knapp and Hartung. We included 15 RCTs (n = 483), most had small-to-modest sample sizes. Comparing active versus sham TMS, active stimulation was significantly superior for OCD symptoms (Hedges g = 0.45; 95% confidence interval, 0.2-0.71). The funnel plot showed that the risk of publication bias was low and between-study heterogeneity was low (I = 43%, P = 0.039 for the χ test). Metaregression showed no particular influence of any variable on the results. Transcranial magnetic stimulation active was superior to sham stimulation for the amelioration of OCD symptoms. Trials had moderate heterogeneity results, despite different protocols of stimulation used. Further RCTs with larger sample sizes are fundamentally needed to clarify the precise impact of TMS in OCD symptoms.

Emotional and physiological reactivity in Complicated Grief.

PubMed

LeBlanc, Nicole J; Unger, Leslie D; McNally, Richard J

2016-04-01

Grief is a psychobiological response to the loss of a loved one. Some grief theorists suggest that this predictable response may arise from withdrawal of psychobiological regulation previously provided by the deceased (e.g. assistance with emotion regulation). Accordingly, recovery from loss may require bereaved individuals to re-establish self-regulatory control to avoid developing Complicated Grief (CG). This model implies that adults with CG may exhibit aberrant emotional responding to environmental stimuli. The present study was designed to test this hypothesis. We recruited a sample of 23 bereaved adults with CG and 26 healthy bereaved adults to complete an emotional reactivity paradigm. Participants watched a series of emotional film clips and provided measures of their self-reported emotional response. We also assessed their heart rate, respiratory sinus arrhythmia (RSA), and skin conductance level in response to these clips. Though emotional and physiological differences between the groups were rare, the CG group exhibited attenuated RSA reactivity to some emotional film clips, suggesting blunted parasympathetic nervous system reactivity in those with the disorder. Limitations include the modest sample size and unequal group sizes. Individuals with CG do not exhibit pervasive differences in emotional and physiological reactivity compared to healthy bereaved individuals. However, we did observe evidence of blunted parasympathetic nervous system reactivity in individuals with CG, which may mediate emotional inflexibility among those who develop the disorder. Copyright © 2016 Elsevier B.V. All rights reserved.

The Twin Peaks in 3-D, as Viewed by the Mars Pathfinder IMP Camera

NASA Image and Video Library

1997-11-04

Twin Peaks are modest-size hills to the southwest of NASA Mars Pathfinder landing site. They were discovered on the first panoramas taken by the IMP camera on the 4th of July, 1997. 3D glasses are necessary to identify surface detail.

24 CFR 1007.20 - Eligible housing.

Code of Federal Regulations, 2010 CFR

2010-04-01

... standards that: (1) Provide sufficient flexibility to permit the use of various designs and materials; and (2) Require each dwelling unit to: (i) Be decent, safe, sanitary, and modest in size and design; (ii... kitchen sink and a partitional bathroom with lavatory, toilet, and bath or shower; and (C) Uses water...

76 FR 28060 - Regional Habitat Conservation Plan, Hays County, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-13

... alternative features the acquisition of a modestly sized, pre-determined preserve system and limits the amount... under Alternative B, this alternative involves a conservation program that utilizes a pre-determined..., adaptive management, and other strategies designed to avoid and minimize harm to the covered species and...

A method for nitrate collection for δ15N and δ18O analysis from waters with low nitrate concentrations

USGS Publications Warehouse

Chang, Cecily C.Y.; Langston, J.; Riggs, M.; Campbell, D.H.; Silva, S.R.; Kendall, C.

1999-01-01

 Recently, methods have been developed to analyze NO3- for δ15N and δ18O, improving our ability to identify NO3- sources and transformations. However, none of the existing methods are suited for waters with low NO3- concentrations (0.7-10 µM). We describe an improved method for collecting and recovering NO3- on exchange columns. To overcome the lengthy collection loading times imposed by the large sample volumes (7-70 L), the sample was prefiltered (0.45 µm) with a large surface area filter. Switching to AG2X anion resin and using a coarser mesh size (100-200) than previous methods also enhanced sample flow. Placement of a cation column in front of the anion column minimized clogging of the anion column by dissolved organic carbon (DOC) accumulation. This also served to minimize transfer of unwanted oxygen atoms from DOC to the 18O portion of the NO3- sample, thereby contaminating the sample and shifting δ18O. The cat-AG2X method is suited for on-site sample collection, making it possible to collect and recover NO3- from low ionic strength waters with modest DOC concentrations (80-800 µM), relieves the investigator of transporting large volumes of water back to the laboratory, and offers a means of sampling rain, snow, snowmelt, and stream samples from access-limited sites.

Sample Acquisition and Caching architecture for the Mars Sample Return mission

NASA Astrophysics Data System (ADS)

Zacny, K.; Chu, P.; Cohen, J.; Paulsen, G.; Craft, J.; Szwarc, T.

This paper presents a Mars Sample Return (MSR) Sample Acquisition and Caching (SAC) study developed for the three rover platforms: MER, MER+, and MSL. The study took into account 26 SAC requirements provided by the NASA Mars Exploration Program Office. For this SAC architecture, the reduction of mission risk was chosen by us as having greater priority than mass or volume. For this reason, we selected a “ One Bit per Core” approach. The enabling technology for this architecture is Honeybee Robotics' “ eccentric tubes” core breakoff approach. The breakoff approach allows the drill bits to be relatively small in diameter and in turn lightweight. Hence, the bits could be returned to Earth with the cores inside them with only a modest increase to the total returned mass, but a significant decrease in complexity. Having dedicated bits allows a reduction in the number of core transfer steps and actuators. It also alleviates the bit life problem, eliminates cross contamination, and aids in hermetic sealing. An added advantage is faster drilling time, lower power, lower energy, and lower Weight on Bit (which reduces Arm preload requirements). Drill bits are based on the BigTooth bit concept, which allows re-use of the same bit multiple times, if necessary. The proposed SAC consists of a 1) Rotary-Percussive Core Drill, 2) Bit Storage Carousel, 3) Cache, 4) Robotic Arm, and 5) Rock Abrasion and Brushing Bit (RABBit), which is deployed using the Drill. The system also includes PreView bits (for viewing of cores prior to caching) and Powder bits for acquisition of regolith or cuttings. The SAC total system mass is less than 22 kg for MER and MER+ size rovers and less than 32 kg for the MSL-size rover.

The relationship between offspring size and fitness: integrating theory and empiricism.

PubMed

Rollinson, Njal; Hutchings, Jeffrey A

2013-02-01

How parents divide the energy available for reproduction between size and number of offspring has a profound effect on parental reproductive success. Theory indicates that the relationship between offspring size and offspring fitness is of fundamental importance to the evolution of parental reproductive strategies: this relationship predicts the optimal division of resources between size and number of offspring, it describes the fitness consequences for parents that deviate from optimality, and its shape can predict the most viable type of investment strategy in a given environment (e.g., conservative vs. diversified bet-hedging). Many previous attempts to estimate this relationship and the corresponding value of optimal offspring size have been frustrated by a lack of integration between theory and empiricism. In the present study, we draw from C. Smith and S. Fretwell's classic model to explain how a sound estimate of the offspring size--fitness relationship can be derived with empirical data. We evaluate what measures of fitness can be used to model the offspring size--fitness curve and optimal size, as well as which statistical models should and should not be used to estimate offspring size--fitness relationships. To construct the fitness curve, we recommend that offspring fitness be measured as survival up to the age at which the instantaneous rate of offspring mortality becomes random with respect to initial investment. Parental fitness is then expressed in ecologically meaningful, theoretically defensible, and broadly comparable units: the number of offspring surviving to independence. Although logistic and asymptotic regression have been widely used to estimate offspring size-fitness relationships, the former provides relatively unreliable estimates of optimal size when offspring survival and sample sizes are low, and the latter is unreliable under all conditions. We recommend that the Weibull-1 model be used to estimate this curve because it provides modest improvements in prediction accuracy under experimentally relevant conditions.

Emergent literacy profiles of preschool-age children with specific language impairment.

PubMed

Cabell, Sonia Q; Lomax, Richard G; Justice, Laura M; Breit-Smith, Allison; Skibbe, Lori E; McGinty, Anita S

2010-12-01

The primary aim of the present study was to explore the heterogeneity of emergent literacy skills among preschool-age children with specific language impairment (SLI) through examination of profiles of performance. Fifty-nine children with SLI were assessed on a battery of emergent literacy skills (i.e., alphabet knowledge, print concepts, emergent writing, rhyme awareness) and oral language skills (i.e., receptive/expressive vocabulary and grammar). Cluster analysis techniques identified three emergent literacy profiles: (1) Highest Emergent Literacy, Strength in Alphabet Knowledge; (2) Average Emergent Literacy, Strength in Print Concepts; and (3) Lowest Emergent Literacy across Skills. After taking into account the contribution of child age, receptive and expressive language skills made a small contribution to the prediction of profile membership. The present findings, which may be characterized as exploratory given the relatively modest sample size, suggest that preschool-age children with SLI display substantial individual differences with regard to their emergent literacy skills and that these differences cannot be fully determined by children's age or oral language performance. Replication of the present findings with a larger sample of children is needed.

Sports Participation and Juvenile Delinquency: A Meta-Analytic Review.

PubMed

Spruit, Anouk; van Vugt, Eveline; van der Put, Claudia; van der Stouwe, Trudy; Stams, Geert-Jan

2016-04-01

Participation in sports activities is very popular among adolescents, and is frequently encouraged among youth. Many psychosocial health benefits in youth are attributed to sports participation, but to what extent this positive influence holds for juvenile delinquency is still not clear on both the theoretical and empirical level. There is much controversy on whether sports participation should be perceived as a protective or a risk factor for the development of juvenile delinquency. A multilevel meta-analysis of 51 published and unpublished studies, with 48 independent samples containing 431 effect sizes and N = 132,366 adolescents, was conducted to examine the relationship between sports participation and juvenile delinquency and possible moderating factors of this association. The results showed that there is no overall significant association between sports participation and juvenile delinquency, indicating that adolescent athletes are neither more nor less delinquent than non-athletes. Some study, sample and sports characteristics significantly moderated the relationship between sports participation and juvenile delinquency. However, this moderating influence was modest. Implications for theory and practice concerning the use of sports to prevent juvenile delinquency are discussed.

Outcomes and lessons from a pilot RCT of a community-based HIV prevention multi-session group intervention for gay men.

PubMed

Harding, R; Bensley, J; Corrigan, N; Franks, L; Stratman, J; Waller, Z; Warner, J

2004-07-01

This paper presents the first outcome evaluation of multi-session groupwork for HIV prevention among gay men in the UK. This community-based RCT recruited 50 men, of whom 42% were HIV-positive or untested, and 32% reported status unknown or serodiscordant UAI in the previous 12 months. No knowledge, skills, attitudinal or behavioural differences were detected between intervention and control at baseline. At eight weeks, those attending the group reported significant gains over their control in making sexual choices, physical safety, HIV and STI transmission knowledge, and sexual negotiation skills. At 20 weeks, significant differences remained for HIV and STI transmission knowledge and comfort with sexual choices. Although no behavioural differences were detected, the aims of the National Prevention Strategy were met. This pilot RCT is appraised in the light of modest sample size and attrition, and recommendations for establishing behavioural outcomes are presented. This study has demonstrated that high-risk community samples can be recruited to multi-session interventions, and has provided feasibility data for future rigorous evaluation designs.

The topomer-sampling model of protein folding

PubMed Central

Debe, Derek A.; Carlson, Matt J.; Goddard, William A.

1999-01-01

Clearly, a protein cannot sample all of its conformations (e.g., ≈3100 ≈ 1048 for a 100 residue protein) on an in vivo folding timescale (<1 s). To investigate how the conformational dynamics of a protein can accommodate subsecond folding time scales, we introduce the concept of the native topomer, which is the set of all structures similar to the native structure (obtainable from the native structure through local backbone coordinate transformations that do not disrupt the covalent bonding of the peptide backbone). We have developed a computational procedure for estimating the number of distinct topomers required to span all conformations (compact and semicompact) for a polypeptide of a given length. For 100 residues, we find ≈3 × 107 distinct topomers. Based on the distance calculated between different topomers, we estimate that a 100-residue polypeptide diffusively samples one topomer every ≈3 ns. Hence, a 100-residue protein can find its native topomer by random sampling in just ≈100 ms. These results suggest that subsecond folding of modest-sized, single-domain proteins can be accomplished by a two-stage process of (i) topomer diffusion: random, diffusive sampling of the 3 × 107 distinct topomers to find the native topomer (≈0.1 s), followed by (ii) intratopomer ordering: nonrandom, local conformational rearrangements within the native topomer to settle into the precise native state. PMID:10077555

X-ray metrology of an array of active edge pixel sensors for use at synchrotron light sources

NASA Astrophysics Data System (ADS)

Plackett, R.; Arndt, K.; Bortoletto, D.; Horswell, I.; Lockwood, G.; Shipsey, I.; Tartoni, N.; Williams, S.

2018-01-01

We report on the production and testing of an array of active edge silicon sensors as a prototype of a large array. Four Medipix3RX.1 chips were bump bonded to four single chip sized Advacam active edge n-on-n sensors. These detectors were then mounted into a 2 by 2 array and tested on B16 at Diamond Light Source with an x-ray beam spot of 2um. The results from these tests, compared with optical metrology demonstrate that this type of sensor is sensitive to the physical edge of the silicon, with only a modest loss of efficiency in the final two rows of pixels. We present the efficiency maps recorded with the microfocus beam and a sample powder diffraction measurement. These results give confidence that this sensor technology can be used effectively in larger arrays of detectors at synchrotron light sources.

Assessing Residential Segregation among Medicaid Recipients with Psychiatric Disability in Philadelphia

ERIC Educational Resources Information Center

Metraux, Stephen; Caplan, Joel M.; Klugman, Dutch; Hadley, Trevor R.

2007-01-01

This study assesses the extent of residential segregation among 15,246 people diagnosed with psychiatric disabilities and receiving Medicaid (MA) in Philadelphia, and an identically sized group of MA recipients serving as matched controls. Results indicate that overall levels of residential segregation among this group were modest at their most…

Experiential Learning Laboratories in Business Schools: The WD-40® for Curriculum Innovation

ERIC Educational Resources Information Center

Boroff, Karen E.; Riley, Elven

2012-01-01

The authors present a case analysis of how a business school brought about curriculum innovation. The school used something borrowed, specifically experiential learning laboratories, and something new to attain measureable curriculum change, with only modest investments. The authors urge that the nimbleness of a medium-size school committed to…

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

Batchelor, D.B.; Carreras, B.A.; Hirshman, S.P.

Significant progress has been made in the development of new modest-size compact stellarator devices that could test optimization principles for the design of a more attractive reactor. These are 3 and 4 field period low-aspect-ratio quasi-omnigenous (QO) stellarators based on an optimization method that targets improved confinement, stability, ease of coil design, low-aspect-ratio, and low bootstrap current.

The Multiple Pendulum Problem via Maple[R

ERIC Educational Resources Information Center

Salisbury, K. L.; Knight, D. G.

2002-01-01

The way in which computer algebra systems, such as Maple, have made the study of physical problems of some considerable complexity accessible to mathematicians and scientists with modest computational skills is illustrated by solving the multiple pendulum problem. A solution is obtained for four pendulums with no restriction on the size of the…

A Meta-analytic Review of Religious or Spiritual Involvement and Social Health among Cancer Patients

PubMed Central

Sherman, Allen C; Merluzzi, Thomas V; Pustejovsky, James E; Park, Crystal L; George, Login; Fitchett, George; Jim, Heather SL; Munoz, Alexis R; Danhauer, Suzanne C; Snyder, Mallory A; Salsman, John M

2015-01-01

Background Religion and spirituality (R/S) play an important role in the daily lives of many cancer patients. There has been great interest in determining whether R/S factors are related to clinically-relevant health outcomes. This meta-analytic review examined associations between dimensions of R/S and social health (e.g., social roles and relationships). Methods A systematic search of PubMed, PsycInfo, Cochrane Library, and CINAHL databases was conducted, and data were extracted by four pairs of investigators. Bivariate associations between specific R/S dimensions and social health outcomes were examined in a meta-analysis using a generalized estimating equation (GEE) approach. Results A total of 78 independent samples encompassing 14,277 patients were included in the meta-analysis. Social health was significantly associated with overall R/S (Fisher z effect size = .20, P< .001), and with each of the R/S dimensions (affective R/S effect size = .32, P< .001; cognitive R/S effect size = .11, P< .01; behavioral R/S effect size = .08, P < .05; and ‘other’ R/S effect size = .13, P < .001). Within these dimensions, specific variables tied to social health included spiritual well-being, spiritual struggle, images of God, R/S beliefs, and composite R/S measures (all P’s < .05). None of the demographic or clinical moderating variables examined was significant. Conclusions Several R/S dimensions are modestly associated with patients’ capacity to maintain satisfying social roles and relationships in the context of cancer. Further research is needed to examine the temporal nature of these associations and the mechanisms that underlie them. PMID:26258730

A prospective study of the trajectories of clinical insight, affective symptoms, and cognitive ability in bipolar disorder

PubMed Central

Depp, Colin A.; Harmell, Alexandrea L.; Savla, Gauri N.; Mausbach, Brent T.; Jeste, Dilip V.; Palmer, Barton W.

2014-01-01

Background Clinical insight in bipolar disorder is associated with treatment adherence and psychosocial outcome. The short-term dynamics of clinical insight in relationship to symptoms and cognitive abilities are unknown. Methods In a prospective observational study, a total of 106 outpatients with bipolar disorder I or II were assessed at baseline, 6 weeks, 12 weeks, and 26 weeks. Participants were administered a comprehensive neuropsychological battery, clinical ratings of manic and depressive symptom severity, and self-reported clinical insight. Lagged correlations and linear mixed-effects models were used to determine the temporal associations between symptoms and insight, as well as the moderating influence of global cognitive abilities. Results At baseline, insight was modestly correlated with severity of manic symptoms, but not with depressive symptoms or cognitive abilities. Insight and depressive symptoms fluctuated to approximately the same extent over time. Both lagged correlations and mixed effects models with lagged effects indicated that the severity of manic symptoms predicted worse insight at later assessments, whereas the converse was not significant. There were no direct or moderating influences of global cognitive abilities. Limitations Our sample size was modest, and included relatively psychiatrically stable outpatients, followed for a six month period. Our results may not generalize to acutely symptomatic patients followed over a longer period. Conclusions Clinical insight varies substantially over time within patients with bipolar disorder. Impaired insight in bipolar disorder is more likely to follow than to precede manic symptoms. PMID:24200153

Exploring the Effects of Stellar Multiplicity on Exoplanet Occurrence Rates

NASA Astrophysics Data System (ADS)

Barclay, Thomas; Shabram, Megan

2017-06-01

Determining the frequency of habitable worlds is a key goal of the Kepler mission. During Kepler's four year investigation it detected thousands of transiting exoplanets with sizes varying from smaller than Mercury to larger than Jupiter. Finding planets was just the first step to determining frequency, and for the past few years the mission team has been modeling the reliability and completeness of the Kepler planet sample. One effect that has not typically been built into occurrence rate statistics is that of stellar multiplicity. If a planet orbits the primary star in a binary or triple star system then the transit depth will be somewhat diluted resulting in a modest underestimation in the planet size. However, if a detected planet orbits a fainter star then the error in measured planet radius can be very significant. We have taken a hypothetical star and planet population and passed that through a Kepler detection model. From this we have derived completeness corrections for a realistic case of a Universe with binary stars and compared that with a model Universe where all stars are single. We report on the impact that binaries have on exoplanet population statistics.

Local Swift-BAT active galactic nuclei prefer circumnuclear star formation

NASA Astrophysics Data System (ADS)

Lutz, D.; Shimizu, T.; Davies, R. I.; Herrera-Camus, R.; Sturm, E.; Tacconi, L. J.; Veilleux, S.

2018-01-01

We use Herschel data to analyze the size of the far-infrared 70 μm emission for z < 0.06 local samples of 277 hosts of Swift-BAT selected active galactic nuclei (AGN), and 515 comparison galaxies that are not detected by BAT. For modest far-infrared luminosities 8.5 10.5 (star formation rates ≳6 M⊙ yr-1), possibly because these are typically reached in more compact regions. Full Table A.1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/609/A9

Structure of health-enhancing behavior in adolescence: a latent-variable approach.

PubMed

Donovan, J E; Jessor, R; Costa, F M

1993-12-01

The structure of the interrelations among a variety of health-enhancing behaviors was examined using structural equation modeling analyses of questionnaire data from 1,280 middle school students and 2,219 high school students. The health-enhancing behaviors included seat belt use, adequate hours of sleep, attention to healthy diet, adequate exercise, low sedentary behavior, and regular toothbrushing. In the middle school sample, all of the health-enhancing behaviors correlated significantly but modestly with each other, except for sleep with toothbrushing. In the high school sample, all but three of the 15 correlations among the behaviors were significant. The results further show that a single underlying factor can account for the modest correlations among these health-enhancing behaviors in both samples. The generality of the single-factor model was also established for male, female, White, Hispanic, and Black students at each school level. These findings provide some support for the existence of health-related lifestyles in adolescence.

Beliefs in genetic determinism and attitudes towards psychiatric genetic research: psychometric scale properties, construct associations, demographic correlates, and cross-cultural comparisons.

PubMed

Voracek, Martin; Swami, Viren; Loibl, Lisa Mariella; Furnham, Adrian

2007-12-01

Using two new scales, this study examined beliefs in genetic determinism and attitudes towards psychiatric genetic research in student samples from Austria, Malaysia, Romania, and the United Kingdom. For both constructs, effects of culture were detectable, whereas those related to key demographics were either small and inconsistent across samples (political orientation and religiosity) or zero (sex and age). Judged from factorial dimensionality and internal consistency, the psychometric properties of both scales were satisfactory. Belief in genetic determinism had lower prevalence and corresponded only modestly to positive attitudes towards psychiatric genetic research which had higher prevalence. The correlations of both constructs with a preference of inequality among social groups (social dominance orientation) were modest and inconsistent across samples. Both scales appear appropriate for cross-cultural applications, in particular for research into lay theories and public perceptions regarding genetic vs environmental effects on human behavior, mental disorders, and behavioral and psychiatric genetic research related to these.

Shared-environmental contributions to high cognitive ability.

PubMed

Kirkpatrick, Robert M; McGue, Matt; Iacono, William G

2009-07-01

Using a combined sample of adolescent twins, biological siblings, and adoptive siblings, we estimated and compared the differential shared-environmentality for high cognitive ability and the shared-environmental variance for the full range of ability during adolescence. Estimates obtained via multiple methods were in the neighborhood of 0.20, and suggest a modest effect of the shared environment on both high and full-range ability. We then examined the association of ability with three measures of the family environment in a subsample of adoptive siblings: parental occupational status, parental education, and disruptive life events. Only parental education showed significant (albeit modest) association with ability in both the biological and adoptive samples. We discuss these results in terms of the need for cognitive-development research to combine genetically sensitive designs and modern statistical methods with broad, thorough environmental measurement.

Characterization of airborne particles at a high-btu coal-gasification pilot plant.

PubMed

Davidson, C I; Santhanam, S; Stetter, J R; Flotard, R D; Gebert, E

1982-12-01

Airborne particles in fugitive emissions have been measured at a slagging fixed-bed coal-gasification pilot plant using lignite. Sampling was conducted during shutdown operations and opening of the gasifier following an aborted startup. Aerosol collected with a Sierra high-volume impactor was subjected to analysis by gas chromatography, mass spectrometry, and scanning electron microscopy; aerosol collected with an Andersen low-volume impactor was subjected to flameless atomic absorption analysis. The data show that the bulk of the trace organic material is associated with small particles: these data are similar to data on ambient air reported in the literature. Particle morphologies resemble those of fly ash from coal combustion, including smooth spheres, vesicular spheres, and crystalline material. Trace element size distributions are bimodal and resemble data for ambient air. Pb-containing particles are generally submicron, while particles containing Al, Fe, and other crustal species are mostly of supermicron size. Aluminum-based aerosol enrichment factors calculated from the lignite composition show that the composition of the aerosol resembles that of the coal, with the exception of modest enrichments of Mg, Na, As, and Pb in the submicron size range. Aerosol enrichment factors based on the earth's crustal composition are somewhat greater than those based on coal composition for several elements, suggesting potential errors in using crustal enrichment data to investigate chemical fractionation during aerosol formation.

Genomic data reveal a loss of diversity in two species of tuco-tucos (genus Ctenomys) following a volcanic eruption.

PubMed

Hsu, Jeremy L; Crawford, Jeremy Chase; Tammone, Mauro N; Ramakrishnan, Uma; Lacey, Eileen A; Hadly, Elizabeth A

2017-11-24

Marked reductions in population size can trigger corresponding declines in genetic variation. Understanding the precise genetic consequences of such reductions, however, is often challenging due to the absence of robust pre- and post-reduction datasets. Here, we use heterochronous genomic data from samples obtained before and immediately after the 2011 eruption of the Puyehue-Cordón Caulle volcanic complex in Patagonia to explore the genetic impacts of this event on two parapatric species of rodents, the colonial tuco-tuco (Ctenomys sociabilis) and the Patagonian tuco-tuco (C. haigi). Previous analyses using microsatellites revealed no post-eruption changes in genetic variation in C. haigi, but an unexpected increase in variation in C. sociabilis. To explore this outcome further, we used targeted gene capture to sequence over 2,000 putatively neutral regions for both species. Our data revealed that, contrary to the microsatellite analyses, the eruption was associated with a small but significant decrease in genetic variation in both species. We suggest that genome-level analyses provide greater power than traditional molecular markers to detect the genetic consequences of population size changes, particularly changes that are recent, short-term, or modest in size. Consequently, genomic analyses promise to generate important new insights into the effects of specific environmental events on demography and genetic variation.

Ethnic Identity and Personal Well-Being of People of Color: A Meta-Analysis

ERIC Educational Resources Information Center

Smith, Timothy B.; Silva, Lynda

2011-01-01

This article summarizes research examining the relationship between the constructs of ethnic identity and personal well-being among people of color in North America. Data from 184 studies analyzed with random effects models yielded an omnibus effect size of r = 0.17, suggesting a modest relationship between the 2 constructs. The relationship was…

The Origins of Writing.

ERIC Educational Resources Information Center

Schmandt-Besserat, Denise

Writing appears to have originated from a modest system of counters or tokens used to keep track of economic goods and transactions. This system of recording appeared in 8000 B. C. in Mesopotamia, or what is now Iraq. The tokens' consistency in shape and size during the next 4,000 years attests to the stability of the agricultural economy and way…

A systematic review on the role of anticonvulsants in the treatment of acute bipolar depression.

PubMed

Reinares, María; Rosa, Adriane R; Franco, Carolina; Goikolea, José Manuel; Fountoulakis, Kostas; Siamouli, Melina; Gonda, Xenia; Frangou, Sophia; Vieta, Eduard

2013-03-01

Despite the high morbidity and mortality associated with bipolar depression, the optimal treatment for this phase is still a matter of debate. The aim of the current review was to provide updated evidence about the efficacy and tolerability of anticonvulsants in the treatment of acute bipolar depression. A comprehensive review of randomized controlled trials (RCTs) evaluating the use of anticonvulsants for the treatment of acute bipolar depression up to June 2011 was conducted by means of the PubMed-Medline database. Eligibility criteria included active comparator-controlled or placebo-controlled randomized studies involving monotherapy or combination therapy. A total of 18 RCTs fulfilled the inclusion criteria. Studies supported the efficacy of divalproex as monotherapy in acute bipolar depression but small sample size was a common methodological limitation. Findings were inconclusive for lamotrigine and carbamazepine although overall lamotrigine may have a beneficial but modest effect. Negative results were found for levetiracetam and gabapentin but the evidence base on these agents is scant. All anticonvulsants were generally well tolerated. No double-blind RCTs were found for the use of other anticonvulsants such as oxcarbazepine, licarbazepine, zonisamide, retigabine, pregabalin, tiagabine, felbamate and vigabatrine in the acute treatment of bipolar depression. To sum up, taking into consideration the efficacy and tolerability profiles of anticonvulsants, current evidence supports the use of divalproex and lamotrigine in the treatment of acute bipolar depression. However, available data for most other anticonvulsants are inconclusive and further RCTs with larger sample sizes are needed before drawing firm conclusions.

Association of TLL1 gene polymorphism (rs1503298, T > C) with coronary heart disease in PREDICT, UDACS and ED cohorts.

PubMed

Zain, Maryam; Awan, Fazli Rabbi; Cooper, Jackie A; Li, Ka Wah; Palmen, Jutta; Acharya, Jay; Howard, Philip; Baig, Shahid M; Elkeles, Robert S; Stephens, Jeffrey W; Ireland, Helen; Humphries, Steve E

2014-09-01

To determine the sequence variant of TLL1 gene (rs1503298, T > C) in three British cohorts (PREDICT, UDACS and ED) of patients with type-2 Diabetes mellitus (T2DM) in order to assess its association with coronary heart disease (CHD). Analytical study. UCL, London, UK. Participants were genotyped in 2011-2012 for TLL1 SNP. Samples and related information were previously collected in 2001-2003 for PREDICT, and in 2001-2002 for UDACS and ED groups. Patients included in PREDICT (n=600), UDACS (n=1020) and ED (n=1240) had Diabetes. TLL1 SNP (rs1503298, T > C) was genotyped using TaqMan technology. Allele frequencies were compared using c2 test, and tested for Hardy-Weinberg equilibrium. The risk of disease was assessed from Odds ratios (OR) with 95% Confidence Intervals (95% CI). Moreover, for the PREDICT cohort, the SNP association was tested with Coronary Artery Calcification (CAC) scores. No significant association was found for this SNP with CHD or CAC scores in these cohorts. This SNP could not be confirmed as a risk factor for CHD in T2DM patients. However, the low power of thesmall sample size available is a limitation to the modest effect on risk. Further studies in larger samples would be useful.

A single-cell assay for telomere DNA content shows increasing telomere length heterogeneity, as well as increasing mean telomere length in human spermatozoa with advancing age.

PubMed

Antunes, Danielle M F; Kalmbach, Keri H; Wang, Fang; Dracxler, Roberta C; Seth-Smith, Michelle L; Kramer, Yael; Buldo-Licciardi, Julia; Kohlrausch, Fabiana B; Keefe, David L

2015-11-01

The effect of age on telomere length heterogeneity in men has not been studied previously. Our aims were to determine the relationship between variation in sperm telomere length (STL), men's age, and semen parameters in spermatozoa from men undergoing in vitro fertilization (IVF) treatment. To perform this prospective cross-sectional pilot study, telomere length was estimated in 200 individual spermatozoa from men undergoing IVF treatment at the NYU Fertility Center. A novel single-cell telomere content assay (SCT-pqPCR) measured telomere length in individual spermatozoa. Telomere length among individual spermatozoa within an ejaculate varies markedly and increases with age. Older men not only have longer STL but also have more variable STL compared to younger men. STL from samples with normal semen parameters was significantly longer than that from samples with abnormal parameters, but STL did not differ between spermatozoa with normal versus abnormal morphology. The marked increase in STL heterogeneity as men age is consistent with a role for ALT during spermatogenesis. No data have yet reported the effect of age on STL heterogeneity. Based on these results, future studies should expand this modest sample size to search for molecular evidence of ALT in human testes during spermatogenesis.

Unplanned Drinking and Alcohol-Related Problems: A Preliminary Test of the Model of Unplanned Drinking Behavior

PubMed Central

Pearson, Matthew R.; Henson, James M.

2013-01-01

Much research links impulsivity with alcohol use and problems. In two studies, unplanned (or impulsive) drinking is assessed directly to determine whether it has direct effects on alcohol use and alcohol-related problems. In study 1, we examined whether unplanned drinking serves as a proximal mediator of the effects of impulsivity-like traits on alcohol-related outcomes. With a sample of 211 college student drinkers, we found that the Unplanned Drinking Scale was significantly related to alcohol use, and perhaps more importantly, had a direct effect on alcohol-related problems even after controlling for frequency and quantity of alcohol use. Further, unplanned drinking partially mediated the effects of negative urgency on alcohol-related problems. In study 2, we examined whether unplanned drinking accounts for unique variance in alcohol-related outcomes when controlling for use of protective behavioral strategies. With a sample of 170 college students, we replicated the findings of Study 1 in that the Unplanned Drinking Scale had a significant direct effect on alcohol-related problems even after controlling for alcohol use; further, this effect was maintained when controlling for use of protective behavioral strategies. Limitations include the modest sample sizes and the cross-sectional design. Future directions for testing the Model of Unplanned Drinking Behavior are proposed. PMID:23276312

Using video feedback to improve early father–infant interaction: A pilot study

PubMed Central

Davies, Beverley; Ramchandani, Paul G.

2013-01-01

Preventive interventions with parents of infants have tended to focus on mothers. Recent research focused on fathers suggests that their involvement in interventions might enhance effectiveness. One effective approach with mothers is the brief, home-based Video-feedback Intervention to promote Positive Parenting (VIPP). This paper is a report of a pilot study of VIPP with fathers to assess its feasibility. Five fathers were recruited from an existing longitudinal study of parents. The primary outcome was acceptability, assessed using a semi-structured questionnaire after completion of the intervention. All fathers completed all sessions of the intervention. Fathers rated the intervention as having had a significant impact on their understanding of their child’s thoughts and feelings, and as having improved their communication and relationship with their baby. Fathers’ feedback was generally positive. The flexibility to conduct sessions at home (or at fathers’ places of work) and the flexible timing of sessions were identified as fundamental to successful delivery. The results of this pilot study are encouraging, as VIPP with fathers was feasible. In light of the modest sample size, and the use of a non-clinical sample, the intervention must be evaluated with larger, clinical samples to evaluate its efficacy with fathers. PMID:22434935

Evolving directions in NASA's planetary rover requirements and technology

NASA Technical Reports Server (NTRS)

Weisbin, C. R.; Montemerlo, Mel; Whittaker, W.

1993-01-01

The evolution of NASA's planning for planetary rovers (that is robotic vehicles which may be deployed on planetary bodies for exploration, science analysis, and construction) and some of the technology that was developed to achieve the desired capabilities is reviewed. The program is comprised of a variety of vehicle sizes and types in order to accommodate a range of potential user needs. This includes vehicles whose weight spans a few kilograms to several thousand kilograms; whose locomotion is implemented using wheels, tracks, and legs; and whose payloads vary from microinstruments to large scale assemblies for construction. Robotic vehicles and their associated control systems, developed in the late 1980's as part of a proposed Mars Rover Sample Return (MRSR) mission, are described. Goals suggested at the time for such a MRSR mission included navigating for one to two years across hundreds of kilometers of Martian surface; traversing a diversity of rugged, unknown terrain; collecting and analyzing a variety of samples; and bringing back selected samples to the lander for return to Earth. Current plans (considerably more modest) which have evolved both from technological 'lessons learned' in the previous period, and modified aspirations of NASA missions are presented. Some of the demonstrated capabilities of the developed machines and the technologies which made these capabilities possible are described.

Do Evidence-Based Youth Psychotherapies Outperform Usual Clinical Care? A Multilevel Meta-Analysis

PubMed Central

Weisz, John R.; Kuppens, Sofie; Eckshtain, Dikla; Ugueto, Ana M.; Hawley, Kristin M.; Jensen-Doss, Amanda

2013-01-01

Context Research across four decades has produced numerous empirically-tested evidence-based psychotherapies (EBPs) for youth psychopathology, developed to improve upon usual clinical interventions. Advocates argue that these should replace usual care; but do the EBPs produce better outcomes than usual care? Objective This question was addressed in a meta-analysis of 52 randomized trials directly comparing EBPs to usual care. Analyses assessed the overall effect of EBPs vs. usual care, and candidate moderators; multilevel analysis was used to address the dependency among effect sizes that is common but typically unaddressed in psychotherapy syntheses. Data Sources The PubMed, PsychINFO, and Dissertation Abstracts International databases were searched for studies from January 1, 1960 – December 31, 2010. Study Selection 507 randomized youth psychotherapy trials were identified. Of these, the 52 studies that compared EBPs to usual care were included in the meta-analysis. Data Extraction Sixteen variables (participant, treatment, and study characteristics) were extracted from each study, and effect sizes were calculated for all EBP versus usual care comparisons. Data Synthesis EBPs outperformed usual care. Mean effect size was 0.29; the probability was 58% that a randomly selected youth receiving an EBP would be better off after treatment than a randomly selected youth receiving usual care. Three variables moderated treatment benefit: Effect sizes decreased for studies conducted outside North America, for studies in which all participants were impaired enough to qualify for diagnoses, and for outcomes reported by people other than the youths and parents in therapy. For certain key groups (e.g., studies using clinically referred samples and diagnosed samples), significant EBP effects were not demonstrated. Conclusions EBPs outperformed usual care, but the EBP advantage was modest and moderated by youth, location, and assessment characteristics. There is room for improvement in EBPs, both in the magnitude and range of their benefit, relative to usual care. PMID:23754332

Is a data set distributed as a power law? A test, with application to gamma-ray burst brightnesses

NASA Technical Reports Server (NTRS)

Wijers, Ralph A. M. J.; Lubin, Lori M.

1994-01-01

We present a method to determine whether an observed sample of data is drawn from a parent distribution that is pure power law. The method starts from a class of statistics which have zero expectation value under the null hypothesis, H(sub 0), that the distribution is a pure power law: F(x) varies as x(exp -alpha). We study one simple member of the class, named the `bending statistic' B, in detail. It is most effective for detection a type of deviation from a power law where the power-law slope varies slowly and monotonically as a function of x. Our estimator of B has a distribution under H(sub 0) that depends only on the size of the sample, not on the parameters of the parent population, and is approximated well by a normal distribution even for modest sample sizes. The bending statistic can therefore be used to test a set of numbers is drawn from any power-law parent population. Since many measurable quantities in astrophysics have distriibutions that are approximately power laws, and since deviations from the ideal power law often provide interesting information about the object of study (e.g., a `bend' or `break' in a luminosity function, a line in an X- or gamma-ray spectrum), we believe that a test of this type will be useful in many different contexts. In the present paper, we apply our test to various subsamples of gamma-ray burst brightness from the first-year Burst and Transient Source Experiment (BATSE) catalog and show that we can only marginally detect the expected steepening of the log (N (greater than C(sub max))) - log (C(sub max)) distribution.

Preliminary examination of the efficacy and safety of a standardized chamomile extract for chronic primary insomnia: a randomized placebo-controlled pilot study.

PubMed

Zick, Suzanna M; Wright, Benjamin D; Sen, Ananda; Arnedt, J Todd

2011-09-22

Despite being the most commonly used herbal for sleep disorders, chamomile's (Matricaria recutita) efficacy and safety for treating chronic primary insomnia is unknown. We examined the preliminary efficacy and safety of chamomile for improving subjective sleep and daytime symptoms in patients with chronic insomnia. We performed a randomized, double-blind, placebo-controlled pilot trial in 34 patients aged 18-65 years with DSM-IV primary insomnia for ≥ 6-months. Patients were randomized to 270 mg of chamomile twice daily or placebo for 28-days. The primary outcomes were sleep diary measures. Secondary outcomes included daytime symptoms, safety assessments, and effect size of these measures. There were no significant differences between groups in changes in sleep diary measures, including total sleep time (TST), sleep efficiency, sleep latency, wake after sleep onset (WASO), sleep quality, and number of awakenings. Chamomile did show modest advantage on daytime functioning, although these did not reach statistical significance. Effect sizes were generally small to moderate (Cohen's d ≤ 0.20 to < 0.60) with sleep latency, night time awakenings, and Fatigue Severity Scale (FSS), having moderate effect sizes in favor of chamomile. However, TST demonstrated a moderate effect size in favor of placebo. There were no differences in adverse events reported by the chamomile group compared to placebo. Chamomile could provide modest benefits of daytime functioning and mixed benefits on sleep diary measures relative to placebo in adults with chronic primary insomnia. However, further studies in select insomnia patients would be needed to investigate these conclusions.

Reef-associated crustacean fauna: biodiversity estimates using semi-quantitative sampling and DNA barcoding

NASA Astrophysics Data System (ADS)

Plaisance, L.; Knowlton, N.; Paulay, G.; Meyer, C.

2009-12-01

The cryptofauna associated with coral reefs accounts for a major part of the biodiversity in these ecosystems but has been largely overlooked in biodiversity estimates because the organisms are hard to collect and identify. We combine a semi-quantitative sampling design and a DNA barcoding approach to provide metrics for the diversity of reef-associated crustacean. Twenty-two similar-sized dead heads of Pocillopora were sampled at 10 m depth from five central Pacific Ocean localities (four atolls in the Northern Line Islands and in Moorea, French Polynesia). All crustaceans were removed, and partial cytochrome oxidase subunit I was sequenced from 403 individuals, yielding 135 distinct taxa using a species-level criterion of 5% similarity. Most crustacean species were rare; 44% of the OTUs were represented by a single individual, and an additional 33% were represented by several specimens found only in one of the five localities. The Northern Line Islands and Moorea shared only 11 OTUs. Total numbers estimated by species richness statistics (Chao1 and ACE) suggest at least 90 species of crustaceans in Moorea and 150 in the Northern Line Islands for this habitat type. However, rarefaction curves for each region failed to approach an asymptote, and Chao1 and ACE estimators did not stabilize after sampling eight heads in Moorea, so even these diversity figures are underestimates. Nevertheless, even this modest sampling effort from a very limited habitat resulted in surprisingly high species numbers.

Maternal depression, stress and feeding styles: towards a framework for theory and research in child obesity

USDA-ARS?s Scientific Manuscript database

Against the background of rising rates of obesity in children and adults in the USA, and modest effect sizes for obesity interventions, the aim of the present narrative review paper is to extend the UNICEF care model to focus on childhood obesity and its associated risks with an emphasis on the emot...

Analysis and design of a 10 to 30 kW grid-connected solar power system for the JPL fire station and first aid station

NASA Technical Reports Server (NTRS)

Josephs, R. H.

1982-01-01

The design and performance of a modestly sized utility-connected power conditioning system and its supporting photovoltaic collector are described and estimated. Utility preparations and guidelines to conform with the output of a small generating station with that of a large power network are examined.

Underplanting northern red oak in Missouri without herbicides.

Treesearch

Paul S. Johnson

1992-01-01

Describes a provisional assessment of the effectiveness of applying herbicides to woody competitors between 0.5- and 1.5- inches d.b.h. before underplanting northern red oak. Results suggest that no weed control, i.e., not using herbicides, would require only modest increases in the numbers or initial size of nursery stock needed to obtain a given future stocking goal...

Fear of Negative Evaluation Influences Eye Gaze in Adolescents with Autism Spectrum Disorder: A Pilot Study

ERIC Educational Resources Information Center

White, Susan W.; Maddox, Brenna B.; Panneton, Robin K.

2015-01-01

Social anxiety is common among adolescents with Autism Spectrum Disorder (ASD). In this modest-sized pilot study, we examined the relationship between social worries and gaze patterns to static social stimuli in adolescents with ASD (n = 15) and gender-matched adolescents without ASD (control; n = 18). Among cognitively unimpaired adolescents with…

Quality, Social Justice and Accountability in Education Worldwide. BCES Conference Books, Volume 13. Number 1

ERIC Educational Resources Information Center

Popov, Nikolay, Ed.; Wolhuter, Charl, Ed.; Ermenc, Klara Skubic, Ed.; Hilton, Gillian, Ed.; Ogunleye, James, Ed.; Niemczyk, Ewelina, Ed.

2015-01-01

The Annual International Conference of the Bulgarian Comparative Education Society is now running in its thirteenth year. From its modest beginnings thirteen years ago, to its impressive size today, a tradition has been the production of a conference book, consistently launched on the first day of the conference each year. This year, Volume 13 of…

The present status and future growth of maintenance in US manufacturing: results from a pilot survey.

PubMed

Jin, Xiaoning; Siegel, David; Weiss, Brian A; Gamel, Ellen; Wang, Wei; Lee, Jay; Ni, Jun

A research study was conducted (1) to examine the practices employed by US manufacturers to achieve productivity goals and (2) to understand what level of intelligent maintenance technologies and strategies are being incorporated into these practices. This study found that the effectiveness and choice of maintenance strategy were strongly correlated to the size of the manufacturing enterprise; there were large differences in adoption of advanced maintenance practices and diagnostics and prognostics technologies between small and medium-sized enterprises (SMEs). Despite their greater adoption of maintenance practices and technologies, large manufacturing organizations have had only modest success with respect to diagnostics and prognostics and preventive maintenance projects. The varying degrees of success with respect to preventative maintenance programs highlight the opportunity for larger manufacturers to improve their maintenance practices and use of advanced prognostics and health management (PHM) technology. The future outlook for manufacturing PHM technology among the manufacturing organizations considered in this study was overwhelmingly positive; many manufacturing organizations have current and planned projects in this area. Given the current modest state of implementation and positive outlook for this technology, gaps, future trends, and roadmaps for manufacturing PHM and maintenance strategy are presented.

Ultrasound-enhanced drug delivery for cancer.

PubMed

Mo, Steven; Coussios, Constantin-C; Seymour, Len; Carlisle, Robert

2012-12-01

Ultrasound, which has traditionally been used as a diagnostic tool, is increasingly being used in non-invasive therapy and drug delivery. Of particular interest to this review is the rapidly accumulating evidence that ultrasound may have a key role to play both in improving the targeting and the efficacy of drug delivery for cancer. Currently available ultrasound-triggerable vehicles are first described, with particular reference to the ultrasonic mechanism that can activate release and the suitability of the size range of the vehicle used for drug delivery. Further mechanical and thermal effects of ultrasound that can enhance extravasation and drug distribution following release are then critically reviewed. Acoustic cavitation is found to play a potentially key role both in achieving targeted drug release and enhanced extravasation at modest pressure amplitudes and acoustic energies, whilst simultaneously enabling real-time monitoring of the drug delivery process. The next challenge in ultrasound-enhanced drug delivery will thus be to develop a new generation of drug-carrying nanoparticles which are of the right size range for delivery to tumours, yet still capable of achieving initiation of cavitation activity and drug release at modest acoustic pressures and energies that have no safety implications for the patient.

The present status and future growth of maintenance in US manufacturing: results from a pilot survey

PubMed Central

Jin, Xiaoning; Siegel, David; Weiss, Brian A.; Gamel, Ellen; Wang, Wei; Lee, Jay; Ni, Jun

2016-01-01

A research study was conducted (1) to examine the practices employed by US manufacturers to achieve productivity goals and (2) to understand what level of intelligent maintenance technologies and strategies are being incorporated into these practices. This study found that the effectiveness and choice of maintenance strategy were strongly correlated to the size of the manufacturing enterprise; there were large differences in adoption of advanced maintenance practices and diagnostics and prognostics technologies between small and medium-sized enterprises (SMEs). Despite their greater adoption of maintenance practices and technologies, large manufacturing organizations have had only modest success with respect to diagnostics and prognostics and preventive maintenance projects. The varying degrees of success with respect to preventative maintenance programs highlight the opportunity for larger manufacturers to improve their maintenance practices and use of advanced prognostics and health management (PHM) technology. The future outlook for manufacturing PHM technology among the manufacturing organizations considered in this study was overwhelmingly positive; many manufacturing organizations have current and planned projects in this area. Given the current modest state of implementation and positive outlook for this technology, gaps, future trends, and roadmaps for manufacturing PHM and maintenance strategy are presented. PMID:27525253

Frequent ultraviolet brightenings observed in a solar active region with solar maximum mission

NASA Technical Reports Server (NTRS)

Porter, J. G.; Toomre, J.; Gebbie, K. B.

1984-01-01

Observations of the temporal behavior of ultraviolet emission from bright points within an active region of the sun are reported. Frequent and rapid brightenings in Si IV and O IV line emission are seen. The observations suggest that intermittent heating events of modest amplitude are occurring at many sites within an active region. By selecting the brightest site at any given time within an active region and then sampling its behavior in detail within a 120 s interval, it is found that about two-thirds of the samples show variations of the Si IV line intensity. The brightenings typically last about 40-60 s; intensity increases of about 20-100 percent are frequently observed. The results suggest that heating due to magnetic field reconnection within an active region is proceeding almost stochastically. Events involving only a modest release of energy occur the most frequently.

Developing a novel risk prediction model for severe malarial anemia.

PubMed

Brickley, E B; Kabyemela, E; Kurtis, J D; Fried, M; Wood, A M; Duffy, P E

2017-01-01

As a pilot study to investigate whether personalized medicine approaches could have value for the reduction of malaria-related mortality in young children, we evaluated questionnaire and biomarker data collected from the Mother Offspring Malaria Study Project birth cohort (Muheza, Tanzania, 2002-2006) at the time of delivery as potential prognostic markers for pediatric severe malarial anemia. Severe malarial anemia, defined here as a Plasmodium falciparum infection accompanied by hemoglobin levels below 50 g/L, is a key manifestation of life-threatening malaria in high transmission regions. For this study sample, a prediction model incorporating cord blood levels of interleukin-1β provided the strongest discrimination of severe malarial anemia risk with a C-index of 0.77 (95% CI 0.70-0.84), whereas a pragmatic model based on sex, gravidity, transmission season at delivery, and bed net possession yielded a more modest C-index of 0.63 (95% CI 0.54-0.71). Although additional studies, ideally incorporating larger sample sizes and higher event per predictor ratios, are needed to externally validate these prediction models, the findings provide proof of concept that risk score-based screening programs could be developed to avert severe malaria cases in early childhood.

Does Council Tax Valuation Band (CTVB) correlate with Under-Privileged Area 8 (UPA8) score and could it be a better 'Jarman Index'?

PubMed Central

Beale, Norman; Taylor, Gordon; Straker-Cook, Dawn

2001-01-01

Background Widespread scepticism persists on the use of the Under-Privileged Area (UPA8) score of Jarman in distributing supplementary resources to so-attributed 'deprived' UK general practices. The search for better 'needs' markers continues. Having already shown that Council Tax Valuation Band (CTVB) is a predictor of UK GP workload, we compare, here, CTVB of residence of a random sample of patients with their respective 'Jarman' scores. Methods Correlation coefficient is calculated between (i) the CTVB of residence of a randomised sample of patients from an English general practice and (ii) the UPA8 scores of the relevant enumeration districts in which they live. Results There is a highly significant correlation between the two measures despite modest study size of 478 patients (85% response). Conclusions The proposal that CTVB is a marker of deprivation and of clinical demand should be examined in more detail: it correlates with 'Jarman', which is already used in NHS resource allocation. But unlike 'Jarman', CTVB is simple, objective, and free of the problems of Census data. CTVB, being household-based, can be aggregated at will. PMID:11716793

Behavioral problems and the occurrence of tobacco, cannabis, and coca paste smoking in Chile: evidence based on multivariate response models for school survey data.

PubMed

Caris, Luis; Anthony, Christopher B; Ríos-Bedoya, Carlos F; Anthony, James C

2009-09-01

In this study we estimate suspected links between youthful behavioral problems and smoking of tobacco, cannabis, and coca paste. In the Republic of Chile, school-attending youths were sampled from all 13 regions of the country, with sample size of 46,907 youths from 8th to 12th grades. A Generalized Estimating Equations (GEE) approach to multiple logistic regression was used to address three interdependent response variables, tobacco smoking, cannabis smoking, and coca paste smoking, and to estimate associations. Drug-specific adjusted slope estimates indicate that youths at the highest levels of behavioral problems are an estimated 1.1 times more likely to have started smoking tobacco, an estimated 1.6 times more likely to have started cannabis smoking, and an estimated 2.0 times more likely to have started coca paste smoking, as compared to youths at the lowest level of behavioral problems (p<0.001). In Chile, there is an association linking behavioral problems with onsets of smoking tobacco and cannabis, as well as coca paste; strength of association is modestly greater for coca paste smoking.

The influence of alexithymia on mobile phone addiction: The role of depression, anxiety and stress.

PubMed

Gao, Tingting; Li, Jiaomeng; Zhang, Han; Gao, Jinglei; Kong, Yixi; Hu, Yueyang; Mei, Songli

2018-01-01

Alexithymia is an important predictor of mobile phone addiction. Enhancing and improving college students' mental health can reduce the rate of mobile phone addiction. However, it is not clear about the role of depression, anxiety and stress in the relationship between college students' alexithymia and mobile phone addiction. A total of 1105 college students were tested with the Toronto Alexithymia Scale, the Depression Anxiety Stress Scale and the Mobile Phone Addiction Index. An individual's level of alexithymia was significantly correlated with depression, anxiety, stress and mobile phone addiction. Alexithymia had a significantly positive prediction effect on mobile phone addiction, and depression, anxiety, and stress on mobile phone are positive predictors. Depression, anxiety or stress had partially mediating effects between alexithymia and mobile phone addiction. Alexithymia not only directly had a positively impact on mobile phone addiction, but both also had an indirect effect on mobile phone addiction through depression, anxiety or stress. Limitations included sampling method and modest sample size, self-report measures, and unmeasured potential confounders. Alexithymia is an important correlate of mobile phone addiction, and depression, anxiety or stress is an important mediator in this relationship. Copyright © 2017 Elsevier B.V. All rights reserved.

Does Council Tax Valuation Band (CTVB) correlate with Under-Privileged Area 8 (UPA8) score and could it be a better 'Jarman Index'?

PubMed

Beale, N; Taylor, G; Straker-Cook, D

2001-01-01

Widespread scepticism persists on the use of the Under-Privileged Area (UPA8) score of Jarman in distributing supplementary resources to so-attributed 'deprived' UK general practices. The search for better 'needs' markers continues. Having already shown that Council Tax Valuation Band (CTVB) is a predictor of UK GP workload, we compare, here, CTVB of residence of a random sample of patients with their respective 'Jarman' scores. Correlation coefficient is calculated between (i) the CTVB of residence of a randomised sample of patients from an English general practice and (ii) the UPA8 scores of the relevant enumeration districts in which they live. There is a highly significant correlation between the two measures despite modest study size of 478 patients (85% response). The proposal that CTVB is a marker of deprivation and of clinical demand should be examined in more detail: it correlates with 'Jarman', which is already used in NHS resource allocation. But unlike 'Jarman', CTVB is simple, objective, and free of the problems of Census data. CTVB, being household-based, can be aggregated at will.

Spatial and temporal variation of an ice-adapted predator's feeding ecology in a changing Arctic marine ecosystem.

PubMed

Yurkowski, David J; Ferguson, Steven H; Semeniuk, Christina A D; Brown, Tanya M; Muir, Derek C G; Fisk, Aaron T

2016-03-01

Spatial and temporal variation can confound interpretations of relationships within and between species in terms of diet composition, niche size, and trophic position (TP). The cause of dietary variation within species is commonly an ontogenetic niche shift, which is a key dynamic influencing community structure. We quantified spatial and temporal variations in ringed seal (Pusa hispida) diet, niche size, and TP during ontogeny across the Arctic-a rapidly changing ecosystem. Stable carbon and nitrogen isotope analysis was performed on 558 liver and 630 muscle samples from ringed seals and on likely prey species from five locations ranging from the High to the Low Arctic. A modest ontogenetic diet shift occurred, with adult ringed seals consuming more forage fish (approximately 80 versus 60 %) and having a higher TP than subadults, which generally decreased with latitude. However, the degree of shift varied spatially, with adults in the High Arctic presenting a more restricted niche size and consuming more Arctic cod (Boreogadus saida) than subadults (87 versus 44 %) and adults at the lowest latitude (29 %). The TPs of adult and subadult ringed seals generally decreased with latitude (4.7-3.3), which was mainly driven by greater complexity in trophic structure within the zooplankton communities. Adult isotopic niche size increased over time, likely due to the recent circumpolar increases in subarctic forage fish distribution and abundance. Given the spatial and temporal variability in ringed seal foraging ecology, ringed seals exhibit dietary plasticity as a species, suggesting adaptability in terms of their diet to climate change.

Quantifying the Variation in the Effective Population Size Within a Genome

PubMed Central

Gossmann, Toni I.; Woolfit, Megan; Eyre-Walker, Adam

2011-01-01

The effective population size (Ne) is one of the most fundamental parameters in population genetics. It is thought to vary across the genome as a consequence of differences in the rate of recombination and the density of selected sites due to the processes of genetic hitchhiking and background selection. Although it is known that there is intragenomic variation in the effective population size in some species, it is not known whether this is widespread or how much variation in the effective population size there is. Here, we test whether the effective population size varies across the genome, between protein-coding genes, in 10 eukaryotic species by considering whether there is significant variation in neutral diversity, taking into account differences in the mutation rate between loci by using the divergence between species. In most species we find significant evidence of variation. We investigate whether the variation in Ne is correlated to recombination rate and the density of selected sites in four species, for which these data are available. We find that Ne is positively correlated to recombination rate in one species, Drosophila melanogaster, and negatively correlated to a measure of the density of selected sites in two others, humans and Arabidopsis thaliana. However, much of the variation remains unexplained. We use a hierarchical Bayesian analysis to quantify the amount of variation in the effective population size and show that it is quite modest in all species—most genes have an Ne that is within a few fold of all other genes. Nonetheless we show that this modest variation in Ne is sufficient to cause significant differences in the efficiency of natural selection across the genome, by demonstrating that the ratio of the number of nonsynonymous to synonymous polymorphisms is significantly correlated to synonymous diversity and estimates of Ne, even taking into account the obvious nonindependence between these measures. PMID:21954163

Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.

PubMed

Sawcer, Stephen; Hellenthal, Garrett; Pirinen, Matti; Spencer, Chris C A; Patsopoulos, Nikolaos A; Moutsianas, Loukas; Dilthey, Alexander; Su, Zhan; Freeman, Colin; Hunt, Sarah E; Edkins, Sarah; Gray, Emma; Booth, David R; Potter, Simon C; Goris, An; Band, Gavin; Oturai, Annette Bang; Strange, Amy; Saarela, Janna; Bellenguez, Céline; Fontaine, Bertrand; Gillman, Matthew; Hemmer, Bernhard; Gwilliam, Rhian; Zipp, Frauke; Jayakumar, Alagurevathi; Martin, Roland; Leslie, Stephen; Hawkins, Stanley; Giannoulatou, Eleni; D'alfonso, Sandra; Blackburn, Hannah; Martinelli Boneschi, Filippo; Liddle, Jennifer; Harbo, Hanne F; Perez, Marc L; Spurkland, Anne; Waller, Matthew J; Mycko, Marcin P; Ricketts, Michelle; Comabella, Manuel; Hammond, Naomi; Kockum, Ingrid; McCann, Owen T; Ban, Maria; Whittaker, Pamela; Kemppinen, Anu; Weston, Paul; Hawkins, Clive; Widaa, Sara; Zajicek, John; Dronov, Serge; Robertson, Neil; Bumpstead, Suzannah J; Barcellos, Lisa F; Ravindrarajah, Rathi; Abraham, Roby; Alfredsson, Lars; Ardlie, Kristin; Aubin, Cristin; Baker, Amie; Baker, Katharine; Baranzini, Sergio E; Bergamaschi, Laura; Bergamaschi, Roberto; Bernstein, Allan; Berthele, Achim; Boggild, Mike; Bradfield, Jonathan P; Brassat, David; Broadley, Simon A; Buck, Dorothea; Butzkueven, Helmut; Capra, Ruggero; Carroll, William M; Cavalla, Paola; Celius, Elisabeth G; Cepok, Sabine; Chiavacci, Rosetta; Clerget-Darpoux, Françoise; Clysters, Katleen; Comi, Giancarlo; Cossburn, Mark; Cournu-Rebeix, Isabelle; Cox, Mathew B; Cozen, Wendy; Cree, Bruce A C; Cross, Anne H; Cusi, Daniele; Daly, Mark J; Davis, Emma; de Bakker, Paul I W; Debouverie, Marc; D'hooghe, Marie Beatrice; Dixon, Katherine; Dobosi, Rita; Dubois, Bénédicte; Ellinghaus, David; Elovaara, Irina; Esposito, Federica; Fontenille, Claire; Foote, Simon; Franke, Andre; Galimberti, Daniela; Ghezzi, Angelo; Glessner, Joseph; Gomez, Refujia; Gout, Olivier; Graham, Colin; Grant, Struan F A; Guerini, Franca Rosa; Hakonarson, Hakon; Hall, Per; Hamsten, Anders; Hartung, Hans-Peter; Heard, Rob N; Heath, Simon; Hobart, Jeremy; Hoshi, Muna; Infante-Duarte, Carmen; Ingram, Gillian; Ingram, Wendy; Islam, Talat; Jagodic, Maja; Kabesch, Michael; Kermode, Allan G; Kilpatrick, Trevor J; Kim, Cecilia; Klopp, Norman; Koivisto, Keijo; Larsson, Malin; Lathrop, Mark; Lechner-Scott, Jeannette S; Leone, Maurizio A; Leppä, Virpi; Liljedahl, Ulrika; Bomfim, Izaura Lima; Lincoln, Robin R; Link, Jenny; Liu, Jianjun; Lorentzen, Aslaug R; Lupoli, Sara; Macciardi, Fabio; Mack, Thomas; Marriott, Mark; Martinelli, Vittorio; Mason, Deborah; McCauley, Jacob L; Mentch, Frank; Mero, Inger-Lise; Mihalova, Tania; Montalban, Xavier; Mottershead, John; Myhr, Kjell-Morten; Naldi, Paola; Ollier, William; Page, Alison; Palotie, Aarno; Pelletier, Jean; Piccio, Laura; Pickersgill, Trevor; Piehl, Fredrik; Pobywajlo, Susan; Quach, Hong L; Ramsay, Patricia P; Reunanen, Mauri; Reynolds, Richard; Rioux, John D; Rodegher, Mariaemma; Roesner, Sabine; Rubio, Justin P; Rückert, Ina-Maria; Salvetti, Marco; Salvi, Erika; Santaniello, Adam; Schaefer, Catherine A; Schreiber, Stefan; Schulze, Christian; Scott, Rodney J; Sellebjerg, Finn; Selmaj, Krzysztof W; Sexton, David; Shen, Ling; Simms-Acuna, Brigid; Skidmore, Sheila; Sleiman, Patrick M A; Smestad, Cathrine; Sørensen, Per Soelberg; Søndergaard, Helle Bach; Stankovich, Jim; Strange, Richard C; Sulonen, Anna-Maija; Sundqvist, Emilie; Syvänen, Ann-Christine; Taddeo, Francesca; Taylor, Bruce; Blackwell, Jenefer M; Tienari, Pentti; Bramon, Elvira; Tourbah, Ayman; Brown, Matthew A; Tronczynska, Ewa; Casas, Juan P; Tubridy, Niall; Corvin, Aiden; Vickery, Jane; Jankowski, Janusz; Villoslada, Pablo; Markus, Hugh S; Wang, Kai; Mathew, Christopher G; Wason, James; Palmer, Colin N A; Wichmann, H-Erich; Plomin, Robert; Willoughby, Ernest; Rautanen, Anna; Winkelmann, Juliane; Wittig, Michael; Trembath, Richard C; Yaouanq, Jacqueline; Viswanathan, Ananth C; Zhang, Haitao; Wood, Nicholas W; Zuvich, Rebecca; Deloukas, Panos; Langford, Cordelia; Duncanson, Audrey; Oksenberg, Jorge R; Pericak-Vance, Margaret A; Haines, Jonathan L; Olsson, Tomas; Hillert, Jan; Ivinson, Adrian J; De Jager, Philip L; Peltonen, Leena; Stewart, Graeme J; Hafler, David A; Hauser, Stephen L; McVean, Gil; Donnelly, Peter; Compston, Alastair

2011-08-10

Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis.

Prescribing Activities that Engage Passive Residents. An Innovative Method

PubMed Central

Kolanowski, Ann; Buettner, Linda

2009-01-01

Individuals with dementia are often passive, which places them at risk for further cognitive and functional decline. Recreational activities have been used in research to reduce passive behaviors, but systematic reviews of these studies have found modest effect sizes for many activities. In this article, we describe the further theoretical development of an innovative method for prescribing activities that have a high likelihood of engaging nursing home residents who are passive and present examples for research application and clinical practice. This method may increase the effect size of activity interventions and encourage more widespread adoption of nonpharmacological interventions in practice. PMID:18274300

The 1883 eruption of Krakatau

NASA Technical Reports Server (NTRS)

Self, S.; Rampino, M. R.

1981-01-01

The 1883 eruption of Krakatau was a modest ignimbrite-forming event. The deposits are primarily coarse-grained dacitic, non-welded ignimbrite. Large explosions produced pyroclastic flows that entered the sea, generating destructive tsunami. Grain-size studies of the ignimbrite suggest that these explosions were not driven by magma-seawater interaction. The total bulk volume of pyroclastic deposits, including co-ignimbrite ash, is estimated to be 18-21 cu km.

Policy Options for University of California Budgeting. Research & Occasional Paper Series: CSHE.5.11

ERIC Educational Resources Information Center

Young, Charles E.

2011-01-01

Within a quarter century after the end of World War II (1945-1970), largely because of the support and investment it received from the State, the University of California had changed from two modest-size general campuses (Berkeley and Los Angeles) and the medical campus in San Francisco (UCSF), to a system of eight general campuses. California was…

Review of benzodiazepine use in children and adolescents.

PubMed

Witek, Malgorzata W; Rojas, Veronica; Alonso, Carmen; Minami, Haruka; Silva, Raul R

2005-01-01

Clinically, benzodiazepines are used in adult populations much more frequently than in children and adolescents. There may be a number of reasons for this disparity including a dearth of well controlled clinical studies and the issue of dependence associated with long term use. However, over a ten year span there has been nearly a three fold increase in the use patterns for these agents in the child population. In open studies much of the literature has indicated potentially useful results, but these findings have not been replicated when more refined methodological studies have been conducted. The lack of encouraging results in these later studies may be attributable to a number of factors such as modest sample sizes and less than optimal patient selection. Nonetheless, with increasing prescriptions being written for these agents it is not clear what is compelling clinicians to use them. In this paper we will review the available literature on benzodiazepine use in the child and adolescent population, focusing primarily on psychiatric applications.

Genetic association analyses implicate aberrant regulation of innate and adaptive immunity genes in the pathogenesis of systemic lupus erythematosus

PubMed Central

Graham, Deborah S Cunninghame; Pinder, Christopher L; Tombleson, Philip; Behrens, Timothy W; Martín, Javier; Fairfax, Benjamin P; Knight, Julian C; Chen, Lingyan; Replogle, Joseph; Syvänen, Ann-Christine; Rönnblom, Lars; Graham, Robert R; Wither, Joan E; Rioux, John D; Alarcón-Riquelme, Marta E; Vyse, Timothy J

2015-01-01

Systemic lupus erythematosus (SLE; OMIM 152700) is a genetically complex autoimmune disease characterized by loss of immune tolerance to nuclear and cell surface antigens. Previous genome-wide association studies (GWAS) had modest sample sizes, reducing their scope and reliability. Our study comprised 7,219 cases and 15,991 controls of European ancestry: a new GWAS, meta-analysis with a published GWAS and a replication study. We have mapped 43 susceptibility loci, including 10 novel associations. Assisted by dense genome coverage, imputation provided evidence for missense variants underpinning associations in eight genes. Other likely causal genes were established by examining associated alleles for cis-acting eQTL effects in a range of ex vivo immune cells. We found an over-representation (n=16) of transcription factors among SLE susceptibility genes. This supports the view that aberrantly regulated gene expression networks in multiple cell types in both the innate and adaptive immune response contribute to the risk of developing SLE. PMID:26502338

European early modern humans and the fate of the Neandertals

PubMed Central

Trinkaus, Erik

2007-01-01

A consideration of the morphological aspects of the earliest modern humans in Europe (more than ≈33,000 B.P.) and the subsequent Gravettian human remains indicates that they possess an anatomical pattern congruent with the autapomorphic (derived) morphology of the earliest (Middle Paleolithic) African modern humans. However, they exhibit a variable suite of features that are either distinctive Neandertal traits and/or plesiomorphic (ancestral) aspects that had been lost among the African Middle Paleolithic modern humans. These features include aspects of neurocranial shape, basicranial external morphology, mandibular ramal and symphyseal form, dental morphology and size, and anteroposterior dental proportions, as well as aspects of the clavicles, scapulae, metacarpals, and appendicular proportions. The ubiquitous and variable presence of these morphological features in the European earlier modern human samples can only be parsimoniously explained as a product of modest levels of assimilation of Neandertals into early modern human populations as the latter dispersed across Europe. This interpretation is in agreement with current analyses of recent and past human molecular data. PMID:17452632

A Robust Method of Measuring Other-Race and Other-Ethnicity Effects: The Cambridge Face Memory Test Format

PubMed Central

McKone, Elinor; Stokes, Sacha; Liu, Jia; Cohan, Sarah; Fiorentini, Chiara; Pidcock, Madeleine; Yovel, Galit; Broughton, Mary; Pelleg, Michel

2012-01-01

Other-race and other-ethnicity effects on face memory have remained a topic of consistent research interest over several decades, across fields including face perception, social psychology, and forensic psychology (eyewitness testimony). Here we demonstrate that the Cambridge Face Memory Test format provides a robust method for measuring these effects. Testing the Cambridge Face Memory Test original version (CFMT-original; European-ancestry faces from Boston USA) and a new Cambridge Face Memory Test Chinese (CFMT-Chinese), with European and Asian observers, we report a race-of-face by race-of-observer interaction that was highly significant despite modest sample size and despite observers who had quite high exposure to the other race. We attribute this to high statistical power arising from the very high internal reliability of the tasks. This power also allows us to demonstrate a much smaller within-race other ethnicity effect, based on differences in European physiognomy between Boston faces/observers and Australian faces/observers (using the CFMT-Australian). PMID:23118912

Improving the Crossing-SIBTEST Statistic for Detecting Non-uniform DIF.

PubMed

Chalmers, R Philip

2018-06-01

This paper demonstrates that, after applying a simple modification to Li and Stout's (Psychometrika 61(4):647-677, 1996) CSIBTEST statistic, an improved variant of the statistic could be realized. It is shown that this modified version of CSIBTEST has a more direct association with the SIBTEST statistic presented by Shealy and Stout (Psychometrika 58(2):159-194, 1993). In particular, the asymptotic sampling distributions and general interpretation of the effect size estimates are the same for SIBTEST and the new CSIBTEST. Given the more natural connection to SIBTEST, it is shown that Li and Stout's hypothesis testing approach is insufficient for CSIBTEST; thus, an improved hypothesis testing procedure is required. Based on the presented arguments, a new chi-squared-based hypothesis testing approach is proposed for the modified CSIBTEST statistic. Positive results from a modest Monte Carlo simulation study strongly suggest the original CSIBTEST procedure and randomization hypothesis testing approach should be replaced by the modified statistic and hypothesis testing method.

Natural Selection in the Great Apes

PubMed Central

Cagan, Alexander; Theunert, Christoph; Laayouni, Hafid; Santpere, Gabriel; Pybus, Marc; Casals, Ferran; Prüfer, Kay; Navarro, Arcadi; Marques-Bonet, Tomas; Bertranpetit, Jaume; Andrés, Aida M.

2016-01-01

Natural selection is crucial for the adaptation of populations to their environments. Here, we present the first global study of natural selection in the Hominidae (humans and great apes) based on genome-wide information from population samples representing all extant species (including most subspecies). Combining several neutrality tests we create a multi-species map of signatures of natural selection covering all major types of natural selection. We find that the estimated efficiency of both purifying and positive selection varies between species and is significantly correlated with their long-term effective population size. Thus, even the modest differences in population size among the closely related Hominidae lineages have resulted in differences in their ability to remove deleterious alleles and to adapt to changing environments. Most signatures of balancing and positive selection are species-specific, with signatures of balancing selection more often being shared among species. We also identify loci with evidence of positive selection across several lineages. Notably, we detect signatures of positive selection in several genes related to brain function, anatomy, diet and immune processes. Our results contribute to a better understanding of human evolution by putting the evidence of natural selection in humans within its larger evolutionary context. The global map of natural selection in our closest living relatives is available as an interactive browser at http://tinyurl.com/nf8qmzh. PMID:27795229

Evaluation of an integrated group cognitive-behavioral treatment for comorbid mood, anxiety, and substance use disorders: A pilot study.

PubMed

Milosevic, Irena; Chudzik, Susan M; Boyd, Susan; McCabe, Randi E

2017-03-01

This paper presents the development and preliminary evaluation of an integrated group cognitive-behavioral treatment (CBT) for comorbid mood, anxiety, and substance use disorders. The 12-session, manualized treatment was developed collaboratively by a mental health program in a teaching hospital and a community-based addictions service and administered in both settings. Results from an uncontrolled effectiveness trial of 29 treatment completers suggest that integrated group CBT may reduce stress and alcohol use symptoms and improve substance refusal self-efficacy. Changes in symptoms of anxiety, depression, and drug use were not significant, although the effect size for anxiety reduction was in the medium range. Nonetheless, the clinical significance of treatment effects on mood, anxiety, and substance use symptoms was modest. Changes in coping skills and quality of life were not significant, although medium-to-large effects were observed for changes in several coping skills. Participants reported being highly satisfied with treatment, found the treatment strategies to be useful, and noted an improvement in their functioning, particularly socially. Methodological and sample size limitations warrant more rigorous follow-up investigations of this treatment. Results are considered in the context of the current literature on integrated psychological treatments for these common comorbidities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Imaging Genetics and Genomics in Psychiatry: A Critical Review of Progress and Potential.

PubMed

Bogdan, Ryan; Salmeron, Betty Jo; Carey, Caitlin E; Agrawal, Arpana; Calhoun, Vince D; Garavan, Hugh; Hariri, Ahmad R; Heinz, Andreas; Hill, Matthew N; Holmes, Andrew; Kalin, Ned H; Goldman, David

2017-08-01

Imaging genetics and genomics research has begun to provide insight into the molecular and genetic architecture of neural phenotypes and the neural mechanisms through which genetic risk for psychopathology may emerge. As it approaches its third decade, imaging genetics is confronted by many challenges, including the proliferation of studies using small sample sizes and diverse designs, limited replication, problems with harmonization of neural phenotypes for meta-analysis, unclear mechanisms, and evidence that effect sizes may be more modest than originally posited, with increasing evidence of polygenicity. These concerns have encouraged the field to grow in many new directions, including the development of consortia and large-scale data collection projects and the use of novel methods (e.g., polygenic approaches, machine learning) that enhance the quality of imaging genetic studies but also introduce new challenges. We critically review progress in imaging genetics and offer suggestions and highlight potential pitfalls of novel approaches. Ultimately, the strength of imaging genetics and genomics lies in their translational and integrative potential with other research approaches (e.g., nonhuman animal models, psychiatric genetics, pharmacologic challenge) to elucidate brain-based pathways that give rise to the vast individual differences in behavior as well as risk for psychopathology. Copyright © 2017 Society of Biological Psychiatry. All rights reserved.

Communication: From close-packed to topologically close-packed: Formation of Laves phases in moderately polydisperse hard-sphere mixtures

NASA Astrophysics Data System (ADS)

Lindquist, Beth A.; Jadrich, Ryan B.; Truskett, Thomas M.

2018-05-01

Particle size polydispersity can help to inhibit crystallization of the hard-sphere fluid into close-packed structures at high packing fractions and thus is often employed to create model glass-forming systems. Nonetheless, it is known that hard-sphere mixtures with modest polydispersity still have ordered ground states. Here, we demonstrate by computer simulation that hard-sphere mixtures with increased polydispersity fractionate on the basis of particle size and a bimodal subpopulation favors the formation of topologically close-packed C14 and C15 Laves phases in coexistence with a disordered phase. The generality of this result is supported by simulations of hard-sphere mixtures with particle-size distributions of four different forms.

Progress and Promise of Attention-Deficit Hyperactivity Disorder Pharmacogenetics

PubMed Central

Froehlich, Tanya E.; McGough, James J.; Stein, Mark A.

2010-01-01

One strategy for understanding variability in attention-deficit hyperactivity disorder (ADHD) medication response, and therefore redressing the current trial-and-error approach to ADHD medication management, is to identify genetic moderators of treatment. This article summarizes ADHD pharmacogenetic investigative efforts to date, which have primarily focused on short-term response to methylphenidate and largely been limited by modest sample sizes. The most well studied genes include the dopamine transporter and dopamine D4 receptor, with additional genes that have been significantly associated with stimulant medication response including the adrenergic α2A-receptor, catechol-O-methyltransferase, D5 receptor, noradrenaline (norepinephrine) transporter protein 1 and synaptosomal-associated protein 25 kDa. Unfortunately, results of current ADHD pharmacogenetic studies have not been entirely consistent, possibly due to differences in study design, medication dosing regimens and outcome measures. Future directions for ADHD pharmacogenetics investigations may include examination of drug-metabolizing enzymes and a wider range of stimulant and non-stimulant medications. In addition, researchers are increasingly interested in going beyond the individual candidate gene approach to investigate gene-gene interactions or pathways, effect modification by additional environmental exposures and whole genome approaches. Advancements in ADHD pharmacogenetics will be facilitated by multi-site collaborations to obtain larger sample sizes using standardized protocols. Although ADHD pharmacogenetic efforts are still in a relatively early stage, their potential clinical applications may include the development of treatment efficacy and adverse effect prediction algorithms that incorporate the interplay of genetic and environmental factors, as well as the development of novel ADHD treatments. PMID:20088618

Meta-analysis of mismatch negativity to simple versus complex deviants in schizophrenia.

PubMed

Avissar, Michael; Xie, Shanghong; Vail, Blair; Lopez-Calderon, Javier; Wang, Yuanjia; Javitt, Daniel C

2018-01-01

Mismatch negativity (MMN) deficits in schizophrenia (SCZ) have been studied extensively since the early 1990s, with the vast majority of studies using simple auditory oddball task deviants that vary in a single acoustic dimension such as pitch or duration. There has been a growing interest in using more complex deviants that violate more abstract rules to probe higher order cognitive deficits. It is still unclear how sensory processing deficits compare to and contribute to higher order cognitive dysfunction, which can be investigated with later attention-dependent auditory event-related potential (ERP) components such as a subcomponent of P300, P3b. In this meta-analysis, we compared MMN deficits in SCZ using simple deviants to more complex deviants. We also pooled studies that measured MMN and P3b in the same study sample and examined the relationship between MMN and P3b deficits within study samples. Our analysis reveals that, to date, studies using simple deviants demonstrate larger deficits than those using complex deviants, with effect sizes in the range of moderate to large. The difference in effect sizes between deviant types was reduced significantly when accounting for magnitude of MMN measured in healthy controls. P3b deficits, while large, were only modestly greater than MMN deficits (d=0.21). Taken together, our findings suggest that MMN to simple deviants may still be optimal as a biomarker for SCZ and that sensory processing dysfunction contributes significantly to MMN deficit and disease pathophysiology. Copyright © 2017 Elsevier B.V. All rights reserved.

Systematic review of proposed definitions of nocturnal polyuria and population-based evidence of their diagnostic accuracy.

PubMed

Olesen, Tine Kold; Denys, Marie-Astrid; Vande Walle, Johan; Everaert, Karel

2018-02-06

Background Evidence of diagnostic accuracy for proposed definitions of nocturnal polyuria is currently unclear. Purpose Systematic review to determine population-based evidence of the diagnostic accuracy of proposed definitions of nocturnal polyuria based on data from frequency-volume charts. Methods Seventeen pre-specified search terms identified 351 unique investigations published from 1990 to 2016 in BIOSIS, Embase, Embase Alerts, International Pharmaceutical Abstract, Medline, and Cochrane. Thirteen original communications were included in this review based on pre-specified exclusion criteria. Data were extracted from each paper regarding subject age, sex, ethnicity, health status, sample size, data collection methods, and diagnostic discrimination of proposed definitions including sensitivity, specificity, positive and negative predictive value. Results The sample size of study cohorts, participant age, sex, ethnicity, and health status varied considerably in 13 studies reporting on the diagnostic performance of seven different definitions of nocturnal polyuria using frequency-volume chart data from 4968 participants. Most study cohorts were small, mono-ethnic, including only Caucasian males aged 50 or higher with primary or secondary polyuria that were compared to a control group of healthy men without nocturia in prospective or retrospective settings. Proposed definitions had poor discriminatory accuracy in evaluations based on data from subjects independent from the original study cohorts with findings being similar regarding the most widely evaluated definition endorsed by ICS. Conclusions Diagnostic performance characteristics for proposed definitions of nocturnal polyuria show poor to modest discrimination and are not based on sufficient level of evidence from representative, multi-ethnic population-based data from both females and males of all adult ages.

Sex Differences in General Knowledge: Meta-Analysis and New Data on the Contribution of School-Related Moderators among High-School Students

PubMed Central

Tran, Ulrich S.; Hofer, Agnes A.; Voracek, Martin

2014-01-01

Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge. PMID:25347190

Sex differences in general knowledge: meta-analysis and new data on the contribution of school-related moderators among high-school students.

PubMed

Tran, Ulrich S; Hofer, Agnes A; Voracek, Martin

2014-01-01

Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge.

Diffusion Tensor Imaging of Central Auditory Pathways in Patients with Sensorineural Hearing Loss: A Systematic Review.

PubMed

Tarabichi, Osama; Kozin, Elliott D; Kanumuri, Vivek V; Barber, Samuel; Ghosh, Satra; Sitek, Kevin R; Reinshagen, Katherine; Herrmann, Barbara; Remenschneider, Aaron K; Lee, Daniel J

2018-03-01

Objective The radiologic evaluation of patients with hearing loss includes computed tomography and magnetic resonance imaging (MRI) to highlight temporal bone and cochlear nerve anatomy. The central auditory pathways are often not studied for routine clinical evaluation. Diffusion tensor imaging (DTI) is an emerging MRI-based modality that can reveal microstructural changes in white matter. In this systematic review, we summarize the value of DTI in the detection of structural changes of the central auditory pathways in patients with sensorineural hearing loss. Data Sources PubMed, Embase, and Cochrane. Review Methods We used the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement checklist for study design. All studies that included at least 1 sensorineural hearing loss patient with DTI outcome data were included. Results After inclusion and exclusion criteria were met, 20 articles were analyzed. Patients with bilateral hearing loss comprised 60.8% of all subjects. Patients with unilateral or progressive hearing loss and tinnitus made up the remaining studies. The auditory cortex and inferior colliculus (IC) were the most commonly studied regions using DTI, and most cases were found to have changes in diffusion metrics, such as fractional anisotropy, compared to normal hearing controls. Detectable changes in other auditory regions were reported, but there was a higher degree of variability. Conclusion White matter changes based on DTI metrics can be seen in patients with sensorineural hearing loss, but studies are few in number with modest sample sizes. Further standardization of DTI using a prospective study design with larger sample sizes is needed.

Preliminary examination of the efficacy and safety of a standardized chamomile extract for chronic primary insomnia: A randomized placebo-controlled pilot study

PubMed Central

2011-01-01

Background Despite being the most commonly used herbal for sleep disorders, chamomile's (Matricaria recutita) efficacy and safety for treating chronic primary insomnia is unknown. We examined the preliminary efficacy and safety of chamomile for improving subjective sleep and daytime symptoms in patients with chronic insomnia. Methods We performed a randomized, double-blind, placebo-controlled pilot trial in 34 patients aged 18-65 years with DSM-IV primary insomnia for ≥ 6-months. Patients were randomized to 270 mg of chamomile twice daily or placebo for 28-days. The primary outcomes were sleep diary measures. Secondary outcomes included daytime symptoms, safety assessments, and effect size of these measures. Results There were no significant differences between groups in changes in sleep diary measures, including total sleep time (TST), sleep efficiency, sleep latency, wake after sleep onset (WASO), sleep quality, and number of awakenings. Chamomile did show modest advantage on daytime functioning, although these did not reach statistical significance. Effect sizes were generally small to moderate (Cohen's d ≤ 0.20 to < 0.60) with sleep latency, night time awakenings, and Fatigue Severity Scale (FSS), having moderate effect sizes in favor of chamomile. However, TST demonstrated a moderate effect size in favor of placebo. There were no differences in adverse events reported by the chamomile group compared to placebo. Conclusion Chamomile could provide modest benefits of daytime functioning and mixed benefits on sleep diary measures relative to placebo in adults with chronic primary insomnia. However, further studies in select insomnia patients would be needed to investigate these conclusions. Trial Registration ClinicalTrials.gov Identifier NCT01286324 PMID:21939549

Towards psychologically adaptive brain-computer interfaces

NASA Astrophysics Data System (ADS)

Myrden, A.; Chau, T.

2016-12-01

Objective. Brain-computer interface (BCI) performance is sensitive to short-term changes in psychological states such as fatigue, frustration, and attention. This paper explores the design of a BCI that can adapt to these short-term changes. Approach. Eleven able-bodied individuals participated in a study during which they used a mental task-based EEG-BCI to play a simple maze navigation game while self-reporting their perceived levels of fatigue, frustration, and attention. In an offline analysis, a regression algorithm was trained to predict changes in these states, yielding Pearson correlation coefficients in excess of 0.45 between the self-reported and predicted states. Two means of fusing the resultant mental state predictions with mental task classification were investigated. First, single-trial mental state predictions were used to predict correct classification by the BCI during each trial. Second, an adaptive BCI was designed that retrained a new classifier for each testing sample using only those training samples for which predicted mental state was similar to that predicted for the current testing sample. Main results. Mental state-based prediction of BCI reliability exceeded chance levels. The adaptive BCI exhibited significant, but practically modest, increases in classification accuracy for five of 11 participants and no significant difference for the remaining six despite a smaller average training set size. Significance. Collectively, these findings indicate that adaptation to psychological state may allow the design of more accurate BCIs.

Low energy cyclotron for radiocarbon dating

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

Welch, J.J.

1984-12-01

The measurement of naturally occurring radioisotopes whose half lives are less than a few hundred million years but more than a few years provides information about the temporal behavior of geologic and climatic processes, the temporal history of meteoritic bodies as well as the production mechanisms of these radioisotopes. A new extremely sensitive technique for measuring these radioisotopes at tandem Van de Graaff and cyclotron facilities has been very successful though the high cost and limited availability have been discouraging. We have built and tested a low energy cyclotron for radiocarbon dating similar in size to a conventional mass spectrometer.more » These tests clearly show that with the addition of a conventional ion source, the low energy cyclotron can perform the extremely high sensitivity /sup 14/C measurements that are now done at accelerator facilities. We found that no significant background is present when the cyclotron is tuned to accelerate /sup 14/C negative ions and the transmission efficiency is adequate to perform radiocarbon dating on milligram samples of carbon. The internal ion source used did not produce sufficient current to detect /sup 14/C directly at modern concentrations. We show how a conventional carbon negative ion source, located outside the cyclotron magnet, would produce sufficient beam and provide for quick sampling to make radiocarbon dating milligram samples with a modest laboratory instrument feasible.« less

Evolving directions in NASA's planetary rover requirements and technology

NASA Astrophysics Data System (ADS)

Weisbin, C. R.; Montemerlo, Mel; Whittaker, W.

1993-10-01

This paper reviews the evolution of NASA's planning for planetary rovers (i.e. robotic vehicles which may be deployed on planetary bodies for exploration, science analysis, and construction) and some of the technology that has been developed to achieve the desired capabilities. The program is comprised of a variety of vehicle sizes and types in order to accommodate a range of potential user needs. This includes vehicles whose weight spans a few kilograms to several thousand kilograms; whose locomotion is implemented using wheels, tracks, and legs; and whose payloads vary from microinstruments to large scale assemblies for construction. We first describe robotic vehicles, and their associated control systems, developed by NASA in the late 1980's as part of a proposed Mars Rover Sample Return (MRSR) mission. Suggested goals at that time for such an MRSR mission included navigating for one to two years across hundreds of kilometers of Martian surface; traversing a diversity of rugged, unknown terrain; collecting and analyzing a variety of samples; and bringing back selected samples to the lander for return to Earth. Subsequently, we present the current plans (considerably more modest) which have evolved both from technological 'lessons learned' in the previous period, and modified aspirations of NASA missions. This paper describes some of the demonstrated capabilities of the developed machines and the technologies which made these capabilities possible.

Evolving directions in NASA's planetary rover requirements and technology

NASA Technical Reports Server (NTRS)

Weisbin, C. R.; Montemerlo, Mel; Whittaker, W.

1993-01-01

This paper reviews the evolution of NASA's planning for planetary rovers (i.e. robotic vehicles which may be deployed on planetary bodies for exploration, science analysis, and construction) and some of the technology that has been developed to achieve the desired capabilities. The program is comprised of a variety of vehicle sizes and types in order to accommodate a range of potential user needs. This includes vehicles whose weight spans a few kilograms to several thousand kilograms; whose locomotion is implemented using wheels, tracks, and legs; and whose payloads vary from microinstruments to large scale assemblies for construction. We first describe robotic vehicles, and their associated control systems, developed by NASA in the late 1980's as part of a proposed Mars Rover Sample Return (MRSR) mission. Suggested goals at that time for such an MRSR mission included navigating for one to two years across hundreds of kilometers of Martian surface; traversing a diversity of rugged, unknown terrain; collecting and analyzing a variety of samples; and bringing back selected samples to the lander for return to Earth. Subsequently, we present the current plans (considerably more modest) which have evolved both from technological 'lessons learned' in the previous period, and modified aspirations of NASA missions. This paper describes some of the demonstrated capabilities of the developed machines and the technologies which made these capabilities possible.

Optical properties of mineral dust aerosol including analysis of particle size, composition, and shape effects, and the impact of physical and chemical processing

NASA Astrophysics Data System (ADS)

Alexander, Jennifer Mary

Atmospheric mineral dust has a large impact on the earth's radiation balance and climate. The radiative effects of mineral dust depend on factors including, particle size, shape, and composition which can all be extremely complex. Mineral dust particles are typically irregular in shape and can include sharp edges, voids, and fine scale surface roughness. Particle shape can also depend on the type of mineral and can vary as a function of particle size. In addition, atmospheric mineral dust is a complex mixture of different minerals as well as other, possibly organic, components that have been mixed in while these particles are suspended in the atmosphere. Aerosol optical properties are investigated in this work, including studies of the effect of particle size, shape, and composition on the infrared (IR) extinction and visible scattering properties in order to achieve more accurate modeling methods. Studies of particle shape effects on dust optical properties for single component mineral samples of silicate clay and diatomaceous earth are carried out here first. Experimental measurements are modeled using T-matrix theory in a uniform spheroid approximation. Previous efforts to simulate the measured optical properties of silicate clay, using models that assumed particle shape was independent of particle size, have achieved only limited success. However, a model which accounts for a correlation between particle size and shape for the silicate clays offers a large improvement over earlier modeling approaches. Diatomaceous earth is also studied as an example of a single component mineral dust aerosol with extreme particle shapes. A particle shape distribution, determined by fitting the experimental IR extinction data, used as a basis for modeling the visible light scattering properties. While the visible simulations show only modestly good agreement with the scattering data, the fits are generally better than those obtained using more commonly invoked particle shape distributions. The next goal of this work is to investigate if modeling methods developed in the studies of single mineral components can be generalized to predict the optical properties of more authentic aerosol samples which are complex mixtures of different minerals. Samples of Saharan sand, Iowa loess, and Arizona road dust are used here as test cases. T-matrix based simulations of the authentic samples, using measured particle size distributions, empirical mineralogies, and a priori particle shape models for each mineral component are directly compared with the measured IR extinction spectra and visible scattering profiles. This modeling approach offers a significant improvement over more commonly applied models that ignore variations in particle shape with size or mineralogy and include only a moderate range of shape parameters. Mineral dust samples processed with organic acids and humic material are also studied in order to explore how the optical properties of dust can change after being aged in the atmosphere. Processed samples include quartz mixed with humic material, and calcite reacted with acetic and oxalic acid. Clear differences in the light scattering properties are observed for all three processed mineral dust samples when compared to the unprocessed mineral dust or organic salt products. These interactions result in both internal and external mixtures depending on the sample. In addition, the presence of these organic materials can alter the mineral dust particle shape. Overall, however, these results demonstrate the need to account for the effects of atmospheric aging of mineral dust on aerosol optical properties. Particle shape can also affect the aerodynamic properties of mineral dust aerosol. In order to account for these effects, the dynamic shape factor is used to give a measure of particle asphericity. Dynamic shape factors of quartz are measured by mass and mobility selecting particles and measuring their vacuum aerodynamic diameter. From this, dynamic shape factors in both the transition and vacuum regime can be derived. The measured dynamic shape factors of quartz agree quite well with the spheroidal shape distributions derived through studies of the optical properties.

Can amorphization take place in nanoscale interconnects?

PubMed

Kumar, S; Joshi, K L; van Duin, A C T; Haque, M A

2012-03-09

The trend of miniaturization has highlighted the problems of heat dissipation and electromigration in nanoelectronic device interconnects, but not amorphization. While amorphization is known to be a high pressure and/or temperature phenomenon, we argue that defect density is the key factor, while temperature and pressure are only the means. For nanoscale interconnects carrying modest current density, large vacancy concentrations may be generated without the necessity of high temperature or pressure due to the large fraction of grain boundaries and triple points. To investigate this hypothesis, we performed in situ transmission electron microscope (TEM) experiments on 200 nm thick (80 nm average grain size) aluminum specimens. Electron diffraction patterns indicate partial amorphization at modest current density of about 10(5) A cm(-2), which is too low to trigger electromigration. Since amorphization results in drastic decrease in mechanical ductility as well as electrical and thermal conductivity, further increase in current density to about 7 × 10(5) A cm(-2) resulted in brittle fracture failure. Our molecular dynamics (MD) simulations predict the formation of amorphous regions in response to large mechanical stresses (due to nanoscale grain size) and excess vacancies at the cathode side of the thin films. The findings of this study suggest that amorphization can precede electromigration and thereby play a vital role in the reliability of micro/nanoelectronic devices.

Page mode reading with simulated scotomas: a modest effect of interline spacing on reading speed.

PubMed

Bernard, Jean-Baptiste; Scherlen, Anne-Catherine; Anne-Catherine, Scherlen; Castet, Eric; Eric, Castet

2007-12-01

Crowding is thought to be one potent limiting factor of reading in peripheral vision. While several studies investigated how crowding between horizontally adjacent letters or words can influence eccentric reading, little attention has been paid to the influence of vertically adjacent lines of text. The goal of this study was to examine the dependence of page mode reading performance (speed and accuracy) on interline spacing. A gaze-contingent visual display was used to simulate a visual central scotoma while normally sighted observers read meaningful French sentences following MNREAD principles. The sensitivity of this new material to low-level factors was confirmed by showing strong effects of perceptual learning, print size and scotoma size on reading performance. In contrast, reading speed was only slightly modulated by interline spacing even for the largest range tested: a 26% gain for a 178% increase in spacing. This modest effect sharply contrasts with the dramatic influence of vertical word spacing found in a recent RSVP study. This discrepancy suggests either that vertical crowding is minimized when reading meaningful sentences, or that the interaction between crowding and other factors such as attention and/or visuo-motor control is dependent on the paradigm used to assess reading speed (page vs. RSVP mode).

Multiple Removal of Spent Rocket Upper Stages with an Ion Beam Shepherd

NASA Astrophysics Data System (ADS)

Bombardelli, C.; Herrera-Montojo, J.; Gonzalo, J. L.

2013-08-01

Among the many advantages of the recently proposed ion beam shepherd (IBS) debris removal technique is the capability to deal with multiple targets in a single mission. A preliminary analysis is here conducted in order to estimate the cost in terms of spacecraft mass and total mission time to remove multiple large-size upper stages of the Zenit family. Zenit-2 upper stages are clustered at 71 degrees inclination around 850 km altitude in low Earth orbit. It is found that a removal of two targets per year is feasible with a modest size spacecraft. The most favorable combinations of targets are outlined.

The Observational Determination of the Age of the Universe as a Laboratory Exercise.

ERIC Educational Resources Information Center

Cadmus, Robert R., Jr.

1999-01-01

Describes a procedure that allows undergraduate students to determine the approximate age of the universe using their own data. The experiment requires a relatively small telescope with a modest spectrograph. Includes sample data and calculations. (Contains 11 references.) (Author/WRM)

Stimulant treatment history predicts frontal-striatal structural connectivity in adolescents with attention-deficit/hyperactivity disorder.

PubMed

Schweren, L J S; Hartman, C A; Zwiers, M P; Heslenfeld, D J; Franke, B; Oosterlaan, J; Buitelaar, J K; Hoekstra, P J

2016-04-01

Diffusion tensor imaging (DTI) has revealed white matter abnormalities in individuals with attention-deficit/hyperactivity disorder (ADHD). Stimulant treatment may affect such abnormalities. The current study investigated associations between long-term stimulant treatment and white matter integrity within the frontal-striatal and mesolimbic pathways, in a large sample of children, adolescents and young adults with ADHD. Participants with ADHD (N=172; mean age 17, range 9-26) underwent diffusion-weighted MRI scanning, along with an age- and gendermatched group of 96 control participants. Five study-specific white matter tract masks (orbitofrontal-striatal, orbitofrontal-amygdalar, amygdalar-striatal, dorsolateral-prefrontal-striatal and medialprefrontal-striatal) were created. First we analyzed case-control differences in fractional anisotropy (FA) and mean diffusivity (MD) within each tract. Second, FA and MD in each tract was predicted from cumulative stimulant intake within the ADHD group. After correction for multiple testing, participants with ADHD showed reduced FA in the orbitofrontal-striatal pathway (p=0.010, effect size=0.269). Within the ADHD group, higher cumulative stimulant intake was associated with lower MD in the same pathway (p=0.011, effect size=-0.164), but not with FA. The association between stimulant treatment and orbitofrontal-striatal MD was of modest effect size. It fell short of significance after adding ADHD severity or ADHD type to the model (p=0.036 and p=0.094, respectively), while the effect size changed little. Our findings are compatible with stimulant treatment enhancing orbitofrontal-striatal white matter connectivity, and emphasize the importance of the orbitofrontal cortex and its connections in ADHD. Longitudinal studies including a drug-naïve baseline assessment are needed to distinguish between-subject variability in ADHD severity from treatment effects. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Predictive Validity of the HKT-R Risk Assessment Tool: Two and 5-Year Violent Recidivism in a Nationwide Sample of Dutch Forensic Psychiatric Patients.

PubMed

Bogaerts, Stefan; Spreen, Marinus; Ter Horst, Paul; Gerlsma, Coby

2018-06-01

This study has examined the predictive validity of the Historical Clinical Future [ Historisch Klinisch Toekomst] Revised risk assessment scheme in a cohort of 347 forensic psychiatric patients, which were discharged between 2004 and 2008 from any of 12 highly secure forensic centers in the Netherlands. Predictive validity was measured 2 and 5 years after release. Official reconviction data obtained from the Dutch Ministry of Security and Justice were used as outcome measures. Violent reoffending within 2 and 5 years after discharge was assessed. With regard to violent reoffending, results indicated that the predictive validity of the Historical domain was modest for 2 (area under the curve [AUC] = .75) and 5 (AUC = .74) years. The predictive validity of the Clinical domain was marginal for 2 (admission: AUC = .62; discharge: AUC = .63) and 5 (admission: AUC = .69; discharge: AUC = .62) years after release. The predictive validity of the Future domain was modest (AUC = .71) for 2 years and low for 5 (AUC = .58) years. The total score of the instrument was modest for 2 years (AUC = .78) and marginal for 5 (AUC = .68) years. Finally, the Final Risk Judgment was modest for 2 years (AUC = .78) and marginal for 5 (AUC = .63) years time at risk. It is concluded that this risk assessment instrument appears to be a satisfactory instrument for risk assessment.

Influence of system size on the properties of a fluid adsorbed in a nanopore: Physical manifestations and methodological consequences

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

Puibasset, Joël, E-mail: puibasset@cnrs-orleans.fr; Kierlik, Edouard, E-mail: edouard.kierlik@upmc.fr; Tarjus, Gilles, E-mail: tarjus@lptl.jussieu.fr

Hysteresis and discontinuities in the isotherms of a fluid adsorbed in a nanopore in general hamper the determination of equilibrium thermodynamic properties, even in computer simulations. A way around this has been to consider both a reservoir of small size and a pore of small extent in order to restrict the fluctuations of density and approach a classical van der Waals loop. We assess this suggestion by thoroughly studying through Monte Carlo simulations and density functional theory the influence of system size on the equilibrium configurations of the adsorbed fluid and on the resulting isotherms. We stress the importance ofmore » pore-symmetry-breaking states that even for modest pore sizes lead to discontinuous isotherms and we discuss the physical relevance of these states and the methodological consequences for computing thermodynamic quantities.« less

Observations of GEO Debris with the Magellan 6.5-m Telescopes

NASA Technical Reports Server (NTRS)

Seitzer, Patrick; Burkhardt, Andrew; Cardonna, Tommaso; Lederer, Susan M.; Cowardin, Heather; Barker, Edwin S.; Abercromby, Kira J.

2012-01-01

Optical observations of geosynchronous orbit (GEO) debris are important to address two questions: 1. What is the distribution function of objects at GEO as a function of brightness? With some assumptions, this can be used to infer a size distribution. 2. Can we determine what the likely composition of individual GEO debris pieces is from studies of the spectral reflectance of these objects? In this paper we report on optical observations with the 6.5-m Magellan telescopes at Las Campanas Observatory in Chile that attempt to answer both questions. Imaging observations over a 0.5 degree diameter field-of-view have detected a significant population of optically faint debris candidates with R > 19th magnitude, corresponding to a size smaller than 20 cm assuming an albedo of 0.175. Many of these objects show brightness variations larger than a factor of 2, suggesting either irregular shapes or albedo variations or both. The object detection rate (per square degree per hour) shows an increase over the rate measured in the 0.6-m MODEST observations, implying an increase in the population at optically fainter levels. Assuming that the albedo distribution is the same for both samples, this corresponds to an increase in the population of smaller size debris. To study the second issue, calibrated reflectance spectroscopy has been obtained of a sample of GEO and near GEO objects with orbits in the public U.S. Space Surveillance Network catalog. With a 6.5-m telescope, the exposures times are short (30 seconds or less), and provide simultaneous wavelength coverage from 4500 to 8000 Angstroms. If the observed objects are tumbling, then simultaneous coverage and short exposure times are essential for a realistic assessment of the object fs spectral signature. We will compare the calibrated spectra with lab-based measurements of simple spacecraft surfaces composed of a single material.

A systematic review of the efficacy of venlafaxine for the treatment of fibromyalgia.

PubMed

VanderWeide, L A; Smith, S M; Trinkley, K E

2015-02-01

Fibromyalgia is a painful disease affecting 1-2% of the United States population. Serotonin and norepinephrine reuptake inhibitors (SNRIs), such as duloxetine and milnacipran, are well studied and frequently used for treating this disorder. However, efficacy data are limited for the SNRI venlafaxine despite its use in nearly a quarter of patients with fibromyalgia. Accordingly, we systematically reviewed the efficacy of venlafaxine for treatment of fibromyalgia. PubMed, Web of Science and the Cochrane Database were searched using the terms 'venlafaxine' and 'fibromyalgia'. Results were classified as primary studies or review articles based on abstract review. References of review articles were evaluated to ensure no primary studies evaluating venlafaxine were overlooked. All clinical studies that investigated venlafaxine for the treatment of fibromyalgia were included and graded on strength of evidence. Five studies met the inclusion criteria, including 4 open-label cohort studies and 1 randomized, controlled trial. Study durations ranged from 6 weeks to 6 months, and study sizes ranged from 11 to 102 participants. Four of the five published studies reported improvement in at least one outcome. Generally consistent improvements were observed in pain-related outcome measures, including the Fibromyalgia Impact Questionnaire (range, 26-29% reduction; n = 2 studies), Visual Analog Scale (range, 36-45% reduction; n = 2 studies), McGill Pain Questionnaire (48% reduction; n = 1 study) and Clinical Global Impression scale (51% had significant score change; n = 1 study). However, the few studies identified were limited by small sample size, inconsistent use of outcomes and methodological concerns. Studies assessing the efficacy of venlafaxine in the treatment of fibromyalgia to date have been limited by small sample size, inconsistent venlafaxine dosing, lack of placebo control and lack of blinding. In the context of these limitations, venlafaxine appears to be at least modestly effective in treating fibromyalgia. Larger randomized controlled trials are needed to further elucidate the full benefit of venlafaxine. © 2014 John Wiley & Sons Ltd.

Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis

PubMed Central

Sawcer, Stephen; Hellenthal, Garrett; Pirinen, Matti; Spencer, Chris C.A.; Patsopoulos, Nikolaos A.; Moutsianas, Loukas; Dilthey, Alexander; Su, Zhan; Freeman, Colin; Hunt, Sarah E.; Edkins, Sarah; Gray, Emma; Booth, David R.; Potter, Simon C.; Goris, An; Band, Gavin; Oturai, Annette Bang; Strange, Amy; Saarela, Janna; Bellenguez, Céline; Fontaine, Bertrand; Gillman, Matthew; Hemmer, Bernhard; Gwilliam, Rhian; Zipp, Frauke; Jayakumar, Alagurevathi; Martin, Roland; Leslie, Stephen; Hawkins, Stanley; Giannoulatou, Eleni; D’alfonso, Sandra; Blackburn, Hannah; Boneschi, Filippo Martinelli; Liddle, Jennifer; Harbo, Hanne F.; Perez, Marc L.; Spurkland, Anne; Waller, Matthew J; Mycko, Marcin P.; Ricketts, Michelle; Comabella, Manuel; Hammond, Naomi; Kockum, Ingrid; McCann, Owen T.; Ban, Maria; Whittaker, Pamela; Kemppinen, Anu; Weston, Paul; Hawkins, Clive; Widaa, Sara; Zajicek, John; Dronov, Serge; Robertson, Neil; Bumpstead, Suzannah J.; Barcellos, Lisa F.; Ravindrarajah, Rathi; Abraham, Roby; Alfredsson, Lars; Ardlie, Kristin; Aubin, Cristin; Baker, Amie; Baker, Katharine; Baranzini, Sergio E.; Bergamaschi, Laura; Bergamaschi, Roberto; Bernstein, Allan; Berthele, Achim; Boggild, Mike; Bradfield, Jonathan P.; Brassat, David; Broadley, Simon A.; Buck, Dorothea; Butzkueven, Helmut; Capra, Ruggero; Carroll, William M.; Cavalla, Paola; Celius, Elisabeth G.; Cepok, Sabine; Chiavacci, Rosetta; Clerget-Darpoux, Françoise; Clysters, Katleen; Comi, Giancarlo; Cossburn, Mark; Cournu-Rebeix, Isabelle; Cox, Mathew B.; Cozen, Wendy; Cree, Bruce A.C.; Cross, Anne H.; Cusi, Daniele; Daly, Mark J.; Davis, Emma; de Bakker, Paul I.W.; Debouverie, Marc; D’hooghe, Marie Beatrice; Dixon, Katherine; Dobosi, Rita; Dubois, Bénédicte; Ellinghaus, David; Elovaara, Irina; Esposito, Federica; Fontenille, Claire; Foote, Simon; Franke, Andre; Galimberti, Daniela; Ghezzi, Angelo; Glessner, Joseph; Gomez, Refujia; Gout, Olivier; Graham, Colin; Grant, Struan F.A.; Guerini, Franca Rosa; Hakonarson, Hakon; Hall, Per; Hamsten, Anders; Hartung, Hans-Peter; Heard, Rob N.; Heath, Simon; Hobart, Jeremy; Hoshi, Muna; Infante-Duarte, Carmen; Ingram, Gillian; Ingram, Wendy; Islam, Talat; Jagodic, Maja; Kabesch, Michael; Kermode, Allan G.; Kilpatrick, Trevor J.; Kim, Cecilia; Klopp, Norman; Koivisto, Keijo; Larsson, Malin; Lathrop, Mark; Lechner-Scott, Jeannette S.; Leone, Maurizio A.; Leppä, Virpi; Liljedahl, Ulrika; Bomfim, Izaura Lima; Lincoln, Robin R.; Link, Jenny; Liu, Jianjun; Lorentzen, Åslaug R.; Lupoli, Sara; Macciardi, Fabio; Mack, Thomas; Marriott, Mark; Martinelli, Vittorio; Mason, Deborah; McCauley, Jacob L.; Mentch, Frank; Mero, Inger-Lise; Mihalova, Tania; Montalban, Xavier; Mottershead, John; Myhr, Kjell-Morten; Naldi, Paola; Ollier, William; Page, Alison; Palotie, Aarno; Pelletier, Jean; Piccio, Laura; Pickersgill, Trevor; Piehl, Fredrik; Pobywajlo, Susan; Quach, Hong L.; Ramsay, Patricia P.; Reunanen, Mauri; Reynolds, Richard; Rioux, John D.; Rodegher, Mariaemma; Roesner, Sabine; Rubio, Justin P.; Rückert, Ina-Maria; Salvetti, Marco; Salvi, Erika; Santaniello, Adam; Schaefer, Catherine A.; Schreiber, Stefan; Schulze, Christian; Scott, Rodney J.; Sellebjerg, Finn; Selmaj, Krzysztof W.; Sexton, David; Shen, Ling; Simms-Acuna, Brigid; Skidmore, Sheila; Sleiman, Patrick M.A.; Smestad, Cathrine; Sørensen, Per Soelberg; Søndergaard, Helle Bach; Stankovich, Jim; Strange, Richard C.; Sulonen, Anna-Maija; Sundqvist, Emilie; Syvänen, Ann-Christine; Taddeo, Francesca; Taylor, Bruce; Blackwell, Jenefer M.; Tienari, Pentti; Bramon, Elvira; Tourbah, Ayman; Brown, Matthew A.; Tronczynska, Ewa; Casas, Juan P.; Tubridy, Niall; Corvin, Aiden; Vickery, Jane; Jankowski, Janusz; Villoslada, Pablo; Markus, Hugh S.; Wang, Kai; Mathew, Christopher G.; Wason, James; Palmer, Colin N.A.; Wichmann, H-Erich; Plomin, Robert; Willoughby, Ernest; Rautanen, Anna; Winkelmann, Juliane; Wittig, Michael; Trembath, Richard C.; Yaouanq, Jacqueline; Viswanathan, Ananth C.; Zhang, Haitao; Wood, Nicholas W.; Zuvich, Rebecca; Deloukas, Panos; Langford, Cordelia; Duncanson, Audrey; Oksenberg, Jorge R.; Pericak-Vance, Margaret A.; Haines, Jonathan L.; Olsson, Tomas; Hillert, Jan; Ivinson, Adrian J.; De Jager, Philip L.; Peltonen, Leena; Stewart, Graeme J.; Hafler, David A.; Hauser, Stephen L.; McVean, Gil; Donnelly, Peter; Compston, Alastair

2011-01-01

Multiple sclerosis (OMIM 126200) is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability.1 Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals;2,3 and systematic attempts to identify linkage in multiplex families have confirmed that variation within the Major Histocompatibility Complex (MHC) exerts the greatest individual effect on risk.4 Modestly powered Genome-Wide Association Studies (GWAS)5-10 have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects play a key role in disease susceptibility.11 Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the Class I region. Immunologically relevant genes are significantly over-represented amongst those mapping close to the identified loci and particularly implicate T helper cell differentiation in the pathogenesis of multiple sclerosis. PMID:21833088

A combined parasitological molecular approach for noninvasive characterization of parasitic nematode communities in wild hosts.

PubMed

Budischak, Sarah A; Hoberg, Eric P; Abrams, Art; Jolles, Anna E; Ezenwa, Vanessa O

2015-09-01

Most hosts are concurrently or sequentially infected with multiple parasites; thus, fully understanding interactions between individual parasite species and their hosts depends on accurate characterization of the parasite community. For parasitic nematodes, noninvasive methods for obtaining quantitative, species-specific infection data in wildlife are often unreliable. Consequently, characterization of gastrointestinal nematode communities of wild hosts has largely relied on lethal sampling to isolate and enumerate adult worms directly from the tissues of dead hosts. The necessity of lethal sampling severely restricts the host species that can be studied, the adequacy of sample sizes to assess diversity, the geographic scope of collections and the research questions that can be addressed. Focusing on gastrointestinal nematodes of wild African buffalo, we evaluated whether accurate characterization of nematode communities could be made using a noninvasive technique that combined conventional parasitological approaches with molecular barcoding. To establish the reliability of this new method, we compared estimates of gastrointestinal nematode abundance, prevalence, richness and community composition derived from lethal sampling with estimates derived from our noninvasive approach. Our noninvasive technique accurately estimated total and species-specific worm abundances, as well as worm prevalence and community composition when compared to the lethal sampling method. Importantly, the rate of parasite species discovery was similar for both methods, and only a modest number of barcoded larvae (n = 10) were needed to capture key aspects of parasite community composition. Overall, this new noninvasive strategy offers numerous advantages over lethal sampling methods for studying nematode-host interactions in wildlife and can readily be applied to a range of study systems. © 2015 John Wiley & Sons Ltd.

Blood pressure loci identified with a gene-centric array.

PubMed

Johnson, Toby; Gaunt, Tom R; Newhouse, Stephen J; Padmanabhan, Sandosh; Tomaszewski, Maciej; Kumari, Meena; Morris, Richard W; Tzoulaki, Ioanna; O'Brien, Eoin T; Poulter, Neil R; Sever, Peter; Shields, Denis C; Thom, Simon; Wannamethee, Sasiwarang G; Whincup, Peter H; Brown, Morris J; Connell, John M; Dobson, Richard J; Howard, Philip J; Mein, Charles A; Onipinla, Abiodun; Shaw-Hawkins, Sue; Zhang, Yun; Davey Smith, George; Day, Ian N M; Lawlor, Debbie A; Goodall, Alison H; Fowkes, F Gerald; Abecasis, Gonçalo R; Elliott, Paul; Gateva, Vesela; Braund, Peter S; Burton, Paul R; Nelson, Christopher P; Tobin, Martin D; van der Harst, Pim; Glorioso, Nicola; Neuvrith, Hani; Salvi, Erika; Staessen, Jan A; Stucchi, Andrea; Devos, Nabila; Jeunemaitre, Xavier; Plouin, Pierre-François; Tichet, Jean; Juhanson, Peeter; Org, Elin; Putku, Margus; Sõber, Siim; Veldre, Gudrun; Viigimaa, Margus; Levinsson, Anna; Rosengren, Annika; Thelle, Dag S; Hastie, Claire E; Hedner, Thomas; Lee, Wai K; Melander, Olle; Wahlstrand, Björn; Hardy, Rebecca; Wong, Andrew; Cooper, Jackie A; Palmen, Jutta; Chen, Li; Stewart, Alexandre F R; Wells, George A; Westra, Harm-Jan; Wolfs, Marcel G M; Clarke, Robert; Franzosi, Maria Grazia; Goel, Anuj; Hamsten, Anders; Lathrop, Mark; Peden, John F; Seedorf, Udo; Watkins, Hugh; Ouwehand, Willem H; Sambrook, Jennifer; Stephens, Jonathan; Casas, Juan-Pablo; Drenos, Fotios; Holmes, Michael V; Kivimaki, Mika; Shah, Sonia; Shah, Tina; Talmud, Philippa J; Whittaker, John; Wallace, Chris; Delles, Christian; Laan, Maris; Kuh, Diana; Humphries, Steve E; Nyberg, Fredrik; Cusi, Daniele; Roberts, Robert; Newton-Cheh, Christopher; Franke, Lude; Stanton, Alice V; Dominiczak, Anna F; Farrall, Martin; Hingorani, Aroon D; Samani, Nilesh J; Caulfield, Mark J; Munroe, Patricia B

2011-12-09

Raised blood pressure (BP) is a major risk factor for cardiovascular disease. Previous studies have identified 47 distinct genetic variants robustly associated with BP, but collectively these explain only a few percent of the heritability for BP phenotypes. To find additional BP loci, we used a bespoke gene-centric array to genotype an independent discovery sample of 25,118 individuals that combined hypertensive case-control and general population samples. We followed up four SNPs associated with BP at our p < 8.56 × 10(-7) study-specific significance threshold and six suggestively associated SNPs in a further 59,349 individuals. We identified and replicated a SNP at LSP1/TNNT3, a SNP at MTHFR-NPPB independent (r(2) = 0.33) of previous reports, and replicated SNPs at AGT and ATP2B1 reported previously. An analysis of combined discovery and follow-up data identified SNPs significantly associated with BP at p < 8.56 × 10(-7) at four further loci (NPR3, HFE, NOS3, and SOX6). The high number of discoveries made with modest genotyping effort can be attributed to using a large-scale yet targeted genotyping array and to the development of a weighting scheme that maximized power when meta-analyzing results from samples ascertained with extreme phenotypes, in combination with results from nonascertained or population samples. Chromatin immunoprecipitation and transcript expression data highlight potential gene regulatory mechanisms at the MTHFR and NOS3 loci. These results provide candidates for further study to help dissect mechanisms affecting BP and highlight the utility of studying SNPs and samples that are independent of those studied previously even when the sample size is smaller than that in previous studies. Copyright © 2011 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Scaling effects of a graphene field effect transistor for radiation detection

NASA Astrophysics Data System (ADS)

Shollar, Zachary Frank

Radiation detectors based on graphene is a burgeoning research topic within the immense field of graphene research. Although papers continue to parse out their mysteries, the devices remain simplistic and small. New fabrication techniques have allowed for millimeter scale and larger monolayer graphene sheets to be grown with increasingly better quality. It is the goal of this thesis to investigate the scaling effects of millimeter scale graphene for radiation detection purposes. To this end, chemical vapor deposition grown monolayer graphene was purchased and transferred to Si/SiO2 substrates. The devices were patterned into simple rectangular strips varying in size from 3000 x 500 mum, 600 x 100 mum, 300 x 50 mum, and 60 x 11 mum. Four metal contacts were patterned onto each strip for electrical characterization. Two probe resistance measurements were performed on all four sizes, at three different lengths along the graphene. Using the field effect, the graphene resistance response was measured at 0 V back-gate voltage to obtain graphene resistivity on SiO2, which showed an increase in resistivity as the graphene strip size increased. Further, the response was measured for varying back-gate sweep ranges and speeds. This lead to the conclusion that strong p-doping was inherent in the graphene strips, as evidenced by charge neutral points located above +50 V. Strong hysteresis observed in those tests alluded to trapped charge having a major effect on voltage sweeps. Mobility values for the graphene strips were extracted from the back-gate voltage sweeps and fixed gate voltage stabilization curves. Mobility values overall were less than 400 cm2 V-1 s-1, and showed a modest increase in mobility as graphene length increased. Lastly, the largest graphene strip had a light response and radiation response measured. Light response showed a dependence on gate voltage magnitude that favored positive gate voltages, on an n-type Silicon substrate. A saturation effect above +15 V seemed apparent with a resistance increase of only 0.61% +/- 0.062% for +15 V to 0.69% +/- 0.097% for the +50 V back-gate. Response of the largest graphene strip size to forward facing alpha irradiation showed a modest 0.32% +/- 0.082% increase in response, for a -15 V back- gate. Overall, millimeter scale graphene field effect devices showed a light and radiation response, proving their viability. However, results showed fabricated samples had numerous defects and were far from pristine. Fabrication of pristine graphene strips at millimeter scales is of concern. Further work into large scale GFET patterning, testing at more length and width dimensions, and further investigating metal contact and carrier transport in millimeter scales is needed.

Small, medium, large or supersize? The development and evaluation of interventions targeted at portion size

PubMed Central

Vermeer, W M; Steenhuis, I H M; Poelman, M P

2014-01-01

In the past decades, portion sizes of high-caloric foods and drinks have increased and can be considered an important environmental obesogenic factor. This paper describes a research project in which the feasibility and effectiveness of environmental interventions targeted at portion size was evaluated. The studies that we conducted revealed that portion size labeling, offering a larger variety of portion sizes, and proportional pricing (that is, a comparable price per unit regardless of the size) were considered feasible to implement according to both consumers and point-of-purchase representatives. Studies into the effectiveness of these interventions demonstrated that the impact of portion size labeling on the (intended) consumption of soft drinks was, at most, modest. Furthermore, the introduction of smaller portion sizes of hot meals in worksite cafeterias in addition to the existing size stimulated a moderate number of consumers to replace their large meals by a small meal. Elaborating on these findings, we advocate further research into communication and marketing strategies related to portion size interventions; the development of environmental portion size interventions as well as educational interventions that improve people's ability to deal with a ‘super-sized' environment; the implementation of regulation with respect to portion size labeling, and the use of nudges to stimulate consumers to select healthier portion sizes. PMID:25033959

Small, medium, large or supersize? The development and evaluation of interventions targeted at portion size.

PubMed

Vermeer, W M; Steenhuis, I H M; Poelman, M P

2014-07-01

In the past decades, portion sizes of high-caloric foods and drinks have increased and can be considered an important environmental obesogenic factor. This paper describes a research project in which the feasibility and effectiveness of environmental interventions targeted at portion size was evaluated. The studies that we conducted revealed that portion size labeling, offering a larger variety of portion sizes, and proportional pricing (that is, a comparable price per unit regardless of the size) were considered feasible to implement according to both consumers and point-of-purchase representatives. Studies into the effectiveness of these interventions demonstrated that the impact of portion size labeling on the (intended) consumption of soft drinks was, at most, modest. Furthermore, the introduction of smaller portion sizes of hot meals in worksite cafeterias in addition to the existing size stimulated a moderate number of consumers to replace their large meals by a small meal. Elaborating on these findings, we advocate further research into communication and marketing strategies related to portion size interventions; the development of environmental portion size interventions as well as educational interventions that improve people's ability to deal with a 'super-sized' environment; the implementation of regulation with respect to portion size labeling, and the use of nudges to stimulate consumers to select healthier portion sizes.

Chemical Insights into the Design and Development of Face-Centered Cubic Ruthenium Catalysts for Fischer-Tropsch Synthesis.

PubMed

Li, Wei-Zhen; Liu, Jin-Xun; Gu, Jun; Zhou, Wu; Yao, Si-Yu; Si, Rui; Guo, Yu; Su, Hai-Yan; Yan, Chun-Hua; Li, Wei-Xue; Zhang, Ya-Wen; Ma, Ding

2017-02-15

Ruthenium is a promising low-temperature catalyst for Fischer-Tropsch synthesis (FTS). However, its scarcity and modest specific activity limit its widespread industrialization. We demonstrate here a strategy for tuning the crystal phase of catalysts to expose denser and active sites for a higher mass-specific activity. Density functional theory calculations show that upon CO dissociation there are a number of open facets with modest barrier available on the face-centered cubic (fcc) Ru but only a few step edges with a lower barrier on conventional hexagonal-closest packed (hcp) Ru. Guided by theoretical calculations, water-dispersible fcc Ru catalysts containing abundant open facets were synthesized and showed an unprecedented mass-specific activity in the aqueous-phase FTS, 37.8 mol CO ·mol Ru -1 ·h -1 at 433 K. The mass-specific activity of the fcc Ru catalysts with an average size of 6.8 nm is about three times larger than the previous best hcp catalyst with a smaller size of 1.9 nm and a higher specific surface area. The origin of the higher mass-specific activity of the fcc Ru catalysts is identified experimentally from the 2 orders of magnitude higher density of the active sites, despite its slightly higher apparent barrier. Experimental results are in excellent agreement with prediction of theory. The great influence of the crystal phases on site distribution and their intrinsic activities revealed here provides a rationale design of catalysts for higher mass-specific activity without decrease of the particle size.

Matching native electrical stimulation by graded chemical stimulation in isolated mouse adrenal chromaffin cells.

PubMed

Fulop, Tiberiu; Smith, Corey

2007-11-30

Adrenal chromaffin cells release multiple transmitters in response to sympathetic stimulation. Modest cell firing, matching sympathetic tone, releases small freely soluble catecholamines. Elevated electrical firing rates matching input under sympathetic stress results in release of catecholamines as well as semi-soluble vaso- and neuro-active peptides packaged within the dense core of the secretory granule. This activity-dependent differential transmitter release has been shown to rely on a mechanistic shift in the mode of exocytosis through the regulated dilation of the secretory fusion pore between granule and cell surface membranes. However, biochemical description of the mechanism regulating fusion pore dilation remains elusive. In the experimental setting, electrical stimulation designed to mimic sympathetic input, is achieved through single-cell voltage-clamp. While precise, this approach is incompatible with biochemical and proteomic analysis, both of which require large sample sizes. We address this limitation in the current study. We describe a bulk chemical stimulation paradigm calibrated to match defined electrical activity. We utilize calcium and single-cell amperometric measurements to match extracellular potassium concentrations to physiological electrical stimulation under sympathetic tone as well as acute stress conditions. This approach provides larger samples of uniformly stimulated cells for determining molecular players in activity-dependent differential transmitter release from adrenal chromaffin cells.

Preparation of Composite Fluoropolymers with Enhanced Dewetting Using Fluorinated Silsesquioxanes as Drop-In Modifiers (Preprint)

DTIC Science & Technology

2010-02-17

Dewetting Using Fluorinated Silsesquioxanes as Drop-In Modifiers (Preprint) 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Scott T... Dewetting Using Fluorinated Silsesquioxanes as Drop-In Modifiers (Preprint) Scott T. Iacono, a,b Stephen M. Budy, a,c Dennis W. Smith, a and...nanometer-sized surface roughness due to POSS aggregation. 23 Likewise, similar dewetting behavior, 90 albeit modest, was observed utilizing partially

Electroform replication of grazing incidence X-ray optics. [spaceborne telescopes

NASA Technical Reports Server (NTRS)

Ulmer, M. P.; Purcell, W. R.; Bedford, D.; Simnett, G. R.

1985-01-01

Work to produce mirrors via electroform replication is reported. Work on small (6 cm by 9 cm) cylindrical pieces and on 40 cm long by 12 cm wide Wolter shaped mirrors is summarized. It is shown that electroforming is a viable technique for producing relatively inexpensive grazing incidence X-ray optics, as long as modest resolution (1 min of arc) and size (12 cm diameter by 40 cm long) are specified.

Dairy foods in a moderate energy restricted diet do not enhance central fat, weight & intra-abdominal adipose tissue loss or reduce adipocyte size & inflammatory markers in overweight & obese adults; Controlled feeding study

USDA-ARS?s Scientific Manuscript database

Background: Research on the role of dairy foods to enhance weight and fat loss when incorporated into a modest weight loss diet has had mixed results. Objective: A 15 week controlled feeding study to answer the question: do dairy foods enhance central fat and weight loss when incorporated in a mode...

Experiences running NASTRAN on the Microvax 2 computer

NASA Technical Reports Server (NTRS)

Butler, Thomas G.; Mitchell, Reginald S.

1987-01-01

The MicroVAX operates NASTRAN so well that the only detectable difference in its operation compared to an 11/780 VAX is in the execution time. On the modest installation described here, the engineer has all of the tools he needs to do an excellent job of analysis. System configuration decisions, system sizing, preparation of the system disk, definition of user quotas, installation, monitoring of system errors, and operation policies are discussed.

A Theoretical Investigation of the Plausibility of Reactions Between Ammonia and Carbonyl Species (Formaldehyde, Acetaldehyde, and Acetone) in Interstellar Ice Analogs at Ultracold Temperatures

NASA Technical Reports Server (NTRS)

Chen, Lina; Woon, David E.

2011-01-01

We have reexamined the reaction between formaldehyde and ammonia, which was previously studied by us and other workers in modestly sized cluster calculations. Larger model systems with up to 12H2O were employed, and reactions of two more carbonyl species, acetaldehyde and acetone, were also carried out. Calculations were performed at the B3LYP/6-31+G** level with bulk solvent effects treated with a polarizable continuum model; limited MP2/6-31+G** calculations were also performed. We found that while the barrier for the concerted proton relay mechanism described in previous work remains modest, it is still prohibitively high for the reaction to occur under the ultracold conditions that prevail in dense interstellar clouds. However, a new pathway emerged in more realistic clusters that involves at least one barrierless step for two of the carbonyl species considered here: ammonia reacts with formaldehyde and acetaldehyde to form a partial charge transfer species in small clusters (4H2O) and a protonated hydroxyamino intermediate species in large clusters (9H2O, 12H2O); modest barriers that decrease sharply with cluster size are found for the analogous processes for the acetone-NH3 reaction. Furthermore, if a second ammonia replaces one of the water molecules in calculations in the 9H2O clusters, deprotonation can occur to yield the same neutral hydroxyamino species that is formed via the original concerted proton relay mechanism. In at least one position, deprotonation is barrierless when zero-point energy is included. In addition to describing the structures and energetics of the reactions between formaldehyde, acetaldehyde, and acetone with ammonia, we report spectroscopic predictions of the observable vibrational features that are expected to be present in ice mixtures of different composition.

Observations of Titan 3C-4 Transtage Fragmentation Debris

NASA Technical Reports Server (NTRS)

Cowardin, Heather; Seitzer, P.; Abercromby, K.; Barker, E.; Cardona, T.; Krisko, P.; Lederer, S.

2013-01-01

The fragmentation of a Titan 3C-4 Transtage (1968-081) on 21 February 1992 is one of only two known break-ups in or near geosynchronous orbit. The original rocket body and 24 pieces of debris are currently being tracked by the US Space Surveillance Network (SSN). The rocket body (SSN# 3432) and several of the original fragments (SSN# 25000, 25001, 30000, and 33511) were observed in survey mode during 2004-2010 using the 0.6-m Michigan Orbital DEbris Survey Telescope (MODEST) in Chile using a broad R filter. This paper will present a size distribution for all calibrated magnitude data acquired on MODEST. Size distribution plots will also be shown using historical models for small fragmentation debris (down to 10 cm) believed to be associated with the Titan break-up. In November 2010, visible broadband photometry (Johnson/Kron-Cousins BVRI) was acquired with the 0.9-m Small and Moderate Aperture Research Telescope System (SMARTS) at the Cerro Tololo Inter-American Observatory (CTIO) in Chile on several Titan fragments (SSN# 25001, 33509, 33510) and the parent rocket body. Color index data will be used to determine the fragment brightness distribution and how the data compares to spacecraft materials measured in the laboratory using similar photometric measurement techniques. In 2012, the SSN added 16 additional fragments to the catalogue. MODEST acquired magnitude data on ten Titan fragments in late 2012 and early 2013. The magnitude distribution of all the observed fragments are analyzed as a function of time. In order to better characterize the breakup fragments spectral measurements were acquired on the original rocket body and five Titan fragments using the 6.5-m Magellan telescopes at Las Campanas Observatory in Chile. The telescopic spectra are compared with laboratory acquired spectra of materials (e.g., Aluminum and various paints) and categorized based on known absorption features for spacecraft materials.

Climatic influences on human body size and proportions: ecological adaptations and secular trends.

PubMed

Katzmarzyk, P T; Leonard, W R

1998-08-01

This study reevaluates the long-standing observation that human morphology varies with climate. Data on body mass, the body mass index [BMI; mass (kg)/stature (m)2], the surface area/body mass ratio, and relative sitting height (RSH; sitting height/stature) were obtained for 223 male samples and 195 female samples derived from studies published since D.F. Roberts' landmark paper "Body weight, race, and climate" in 1953 (Am. J. Phys. Anthropol. 11:533-558). Current analyses indicate that body mass varies inversely with mean annual temperature in males (r=-0.27, P < 0.001) and females (r=-0.28, P < 0.001), as does the BMI (males: r=-0.22, P=0.001; females: r=-0.30, P < 0.001). The surface area/body mass ratio is positively correlated with temperature in both sexes (males: r=0.29, P < 0.001; females: r=0.34, P < 0.001), whereas the relationship between RSH and temperature is negative (males: r=-0.37, P < 0.001; females: r=-0.46, P < 0.001). These results are consistent with previous work showing that humans follow the ecological rules of Bergmann and Allen. However, the slope of the best-fit regressions between measures of body mass (i.e., mass, BMI, and surface area/mass) and temperature are more modest than those presented by Roberts. These differences appear to be attributable to secular trends in mass, particularly among tropical populations. Body mass and the BMI have increased over the last 40 years, whereas the surface area/body mass ratio has decreased. These findings indicate that, although climatic factors continue to be significant correlates of world-wide variation in human body size and morphology, differential changes in nutrition among tropical, developing world populations have moderated their influence.

The relationship between job satisfaction and health: a meta-analysis.

PubMed

Faragher, E B; Cass, M; Cooper, C L

2005-02-01

A vast number of published studies have suggested a link between job satisfaction levels and health. The sizes of the relationships reported vary widely. Narrative overviews of this relationship have been published, but no systematic meta-analysis review has been conducted. A systematic review and meta-analysis of 485 studies with a combined sample size of 267 995 individuals was conducted, evaluating the research evidence linking self-report measures of job satisfaction to measures of physical and mental wellbeing. The overall correlation combined across all health measures was r = 0.312 (0.370 after Schmidt-Hunter adjustment). Job satisfaction was most strongly associated with mental/psychological problems; strongest relationships were found for burnout (corrected r = 0.478), self-esteem(r = 0.429), depression (r = 0.428), and anxiety(r = 0.420). The correlation with subjective physical illness was more modest (r = 0.287). Correlations in excess of 0.3 are rare in this context. The relationships found suggest that job satisfaction level is an important factor influencing the health of workers. Organisations should include the development of stress management policies to identify and eradicate work practices that cause most job dissatisfaction as part of any exercise aimed at improving employee health. Occupational health clinicians should consider counselling employees diagnosed as having psychological problems to critically evaluate their work-and help them to explore ways of gaining greater satisfaction from this important aspect of their life.

High Contrast Science Program for the Exo-C Space Telescope Mission

NASA Astrophysics Data System (ADS)

Stapelfeldt, Karl R.; Marley, Mark S.; Bryden, Geoffrey; Meadows, Victoria; Belikov, Ruslan; McElwain, Michael W.; Exo-C Science; Technology Definition Team

2015-01-01

Exo-C is a detailed study of the science capability, engineering design, technology requirements, and costing for a modest-aperture space telescope with an internal coronagraph that could directly image exoplanetary systems. During its three year mission, Exo-C will carry out imaging and spectroscopy over the wavelength range 0.45-1.0 um towards the following goals: 1) Characterize the atmospheres of at least a dozen known, nearby radial velocity planets. Exo-C spectra will diagnose their atmospheric composition and the presence of clouds, performing the first such measurements of cool giant exoplanets like those in our own solar system. 2) Conduct an imaging survey of at least 100 additional nearby stars down to ~3e-10 contrast, enabling the discovery of new exoplanets down to super-Earth sizes. Sub-Neptune and super-Earth planets are relatively common in the exoplanet population, but have no counterparts in our Solar System. Exo-C spectra will provide the first atmospheric characterization for these intriguing objects. 3) Image several hundred circumstellar disks, revealing structures induced by planetary perturbations and the time evolution of disk properties. If exozodi is low and a very stable telescope can be achieved, habitable zone planets down to Earth size might be detected in a small sample of nearby stars including the alpha Cen system. Science targets, observing protocols, and future work will be discussed.

Selection of assessment methods for evaluating banana weevil Cosmopolites sordidus (Coleoptera: Curculionidae) damage on highland cooking banana (Musa spp., genome group AAA-EA).

PubMed

Gold, C S; Ragama, P E; Coe, R; Rukazambuga, N D T M

2005-04-01

Cosmopolites sordidus (Germar) is an important pest on bananas and plantains. Population build-up is slow and damage becomes increasingly important in successive crop cycles (ratoons). Yield loss results from plant loss, mat disappearance and reduced bunch size. Damage assessment requires destructive sampling and is most often done on corms of recently harvested plants. A wide range of damage assessment methods exist and there are no agreed protocols. It is critical to know what types of damage best reflect C. sordidus pest status through their relationships with yield loss. Multiple damage assessment parameters (i.e. for the corm periphery, cortex and central cylinder) were employed in two yield loss trials and a cultivar-screening trial in Uganda. Damage to the central cylinder had a greater effect on plant size and yield loss than damage to the cortex or corm periphery. In some cases, a combined assessment of damage to the central cylinder and cortex showed a better relationship with yield loss than an assessment of the central cylinder alone. Correlation, logistic and linear regression analyses showed weak to modest correlations between damage to the corm periphery and damage to the central cylinder. Thus, damage to the corm periphery is not a strong predictor of the more important damage to the central cylinder. Therefore, C. sordidus damage assessment should target the central cylinder and cortex.

Effectiveness of Social Media-based Interventions on Weight-related Behaviors and Body Weight Status: Review and Meta-analysis.

PubMed

An, Ruopeng; Ji, Mengmeng; Zhang, Sheng

2017-11-01

We reviewed scientific literature regarding the effectiveness of social media-based interventions about weight-related behaviors and body weight status. A keyword search were performed in May 2017 in the Clinical-Trials.gov, Cochrane Library, PsycINFO, PubMed, and Web of Science databases. We conducted a meta-analysis to estimate the pooled effect size of social media-based interventions on weight-related outcome measures. We identified 22 interventions from the keyword and reference search, including 12 randomized controlled trials, 6 pre-post studies and 3 cohort studies conducted in 9 countries during 2010-2016. The majority (N = 17) used Facebook, followed by Twitter (N = 4) and Instagram (N = 1). Intervention durations averaged 17.8 weeks with a mean sample size of 69. The meta-analysis showed that social media-based interventions were associated with a statistically significant, but clinically modest reduction of body weight by 1.01 kg, body mass index by 0.92 kg/m2, and waist circumstance by 2.65 cm, and an increase of daily number of steps taken by 1530. In the meta-regression there was no doseresponse effect with respect to intervention duration. The boom of social media provides an unprecedented opportunity to implement health promotion programs. Future interventions should make efforts to improve intervention scalability and effectiveness.

The FoCal prototype—an extremely fine-grained electromagnetic calorimeter using CMOS pixel sensors

NASA Astrophysics Data System (ADS)

de Haas, A. P.; Nooren, G.; Peitzmann, T.; Reicher, M.; Rocco, E.; Röhrich, D.; Ullaland, K.; van den Brink, A.; van Leeuwen, M.; Wang, H.; Yang, S.; Zhang, C.

2018-01-01

A prototype of a Si-W EM calorimeter was built with Monolithic Active Pixel Sensors as the active elements. With a pixel size of 30 μm it allows digital calorimetry, i.e. the particle's energy is determined by counting pixels, not by measuring the energy deposited. Although of modest size, with a width of only four Moliere radii, it has 39 million pixels. In this article the construction and tuning of the prototype is described. Results from beam tests are compared with predictions of GEANT-based Monte Carlo simulations. The shape of showers caused by electrons is shown in unprecedented detail. Results for energy and position resolution are also given.

Some practical aspects of lossless and nearly-lossless compression of AVHRR imagery

NASA Technical Reports Server (NTRS)

Hogan, David B.; Miller, Chris X.; Christensen, Than Lee; Moorti, Raj

1994-01-01

Compression of Advanced Very high Resolution Radiometers (AVHRR) imagery operating in a lossless or nearly-lossless mode is evaluated. Several practical issues are analyzed including: variability of compression over time and among channels, rate-smoothing buffer size, multi-spectral preprocessing of data, day/night handling, and impact on key operational data applications. This analysis is based on a DPCM algorithm employing the Universal Noiseless Coder, which is a candidate for inclusion in many future remote sensing systems. It is shown that compression rates of about 2:1 (daytime) can be achieved with modest buffer sizes (less than or equal to 2.5 Mbytes) and a relatively simple multi-spectral preprocessing step.

Meta-analysis of Theory of Mind (ToM) impairment in bipolar disorder.

PubMed

Bora, E; Bartholomeusz, C; Pantelis, C

2016-01-01

Theory of mind (ToM) dysfunction is prominent in a number of psychiatric disorders, in particular, autism and schizophrenia, and can play a significant role in poor functioning. There is now emerging evidence suggesting that ToM abilities are also impaired in bipolar disorder (BP); however, the relationship between ToM deficits and mood state is not clear. We conducted a meta-analysis of ToM studies in BP. Thirty-four studies comparing 1214 patients with BP and 1097 healthy controls were included. BP groups included remitted (18 samples, 545 BP patients), subsyndromal (12 samples, 510 BP patients), and acute (manic and/or depressed) (10 samples, 159 BP patients) patients. ToM performance was significantly impaired in BP compared to controls. This impairment was evident across different types of ToM tasks (including affective/cognitive and verbal/visual) and was also evident in strictly euthymic patients with BP (d = 0.50). There were no significant differences between remitted and subsyndromal samples. However, ToM deficit was significantly more severe during acute episodes (d = 1.23). ToM impairment was significantly associated with neurocognitive and particularly with manic symptoms. Significant but modest sized ToM dysfunction is evident in remitted and subsyndromal BP. Acute episodes are associated with more robust ToM deficits. Exacerbation of ToM deficits may contribute to the more significant interpersonal problems observed in patients with acute or subsyndromal manic symptoms. There is a need for longitudinal studies comparing the developmental trajectory of ToM deficits across the course of the illness.

Accounting for Diversity in Suicide Research: Sampling and Sample Reporting Practices in the United States.

PubMed

Cha, Christine B; Tezanos, Katherine M; Peros, Olivia M; Ng, Mei Yi; Ribeiro, Jessica D; Nock, Matthew K; Franklin, Joseph C

2018-04-01

Research on suicidal thoughts and behaviors (STB) has identified many risk factors, but whether these findings generalize to diverse populations remains unclear. We review longitudinal studies on STB risk factors over the past 50 years in the United States and evaluate the methodological practices of sampling and reporting sample characteristics. We found that articles frequently reported participant age and sex, less frequently reported participant race and ethnicity, and rarely reported participant veteran status or lesbian, gay, bisexual, and transgender status. Sample reporting practices modestly and inconsistently improved over time. Finally, articles predominantly featured White, non-Hispanic, young adult samples. © 2017 The American Association of Suicidology.

Production of lunar fragmental material by meteoroid impact.

NASA Technical Reports Server (NTRS)

Marcus, A. H.

1973-01-01

The rate of production of new fragmental lunar surface material is derived theoretically on the hypothesis that such material is excavated from a bedrock layer by meteoroid impacts. An overlaying regolith effectively shields the bedrock layer from small impacts, reducing the production rate of centimeter-sized and smaller blocks by a large factor. Logarithmic production rate curves for centimeter to motor-sized blocks are nonlinear for any regolith from centimeters to tens of meters in thickness, with small blocks relatively much less frequent for thicker (older) regoliths, suggesting the possibility of a statistical reverse bedding. Modest variations in the exponents of scaling laws for crater depth-diameter ratio and maximum block-diameter to crater diameter ratio are shown to have significant effects on the production rates. The production rate increases slowly with increasing size of the largest crater affecting the region.

The Effect of Transcranial Direct Current Stimulation (tDCS) Electrode Size and Current Intensity on Motor Cortical Excitability: Evidence From Single and Repeated Sessions.

PubMed

Ho, Kerrie-Anne; Taylor, Janet L; Chew, Taariq; Gálvez, Verònica; Alonzo, Angelo; Bai, Siwei; Dokos, Socrates; Loo, Colleen K

2016-01-01

Current density is considered an important factor in determining the outcomes of tDCS, and is determined by the current intensity and electrode size. Previous studies examining the effect of these parameters on motor cortical excitability with small sample sizes reported mixed results. This study examined the effect of current intensity (1 mA, 2 mA) and electrode size (16 cm(2), 35 cm(2)) on motor cortical excitability over single and repeated tDCS sessions. Data from seven studies in 89 healthy participants were pooled for analysis. Single-session data were analyzed using mixed effects models and repeated-session data were analyzed using mixed design analyses of variance. Computational modeling was used to examine the electric field generated. The magnitude of increases in excitability after anodal tDCS was modest. For single-session tDCS, the 35 cm(2) electrodes produced greater increases in cortical excitability compared to the 16 cm(2) electrodes. There were no differences in the magnitude of cortical excitation produced by 1 mA and 2 mA tDCS. The repeated-sessions data also showed that there were greater increases in excitability with the 35 cm(2) electrodes. Further, repeated sessions of tDCS with the 35 cm(2) electrodes resulted in a cumulative increase in cortical excitability. Computational modeling predicted higher electric field at the motor hotspot for the 35 cm(2) electrodes. 2 mA tDCS does not necessarily produce larger effects than 1 mA tDCS in healthy participants. Careful consideration should be given to the exact positioning, size and orientation of tDCS electrodes relative to cortical regions. Copyright © 2016 Elsevier Inc. All rights reserved.

Predicting Sensitivity of Breast Tumors to Src-targeted Therapies Through Assessment of Cas/Src/BCAR3 Activity

DTIC Science & Technology

2017-10-01

expression is elevated in DCIS samples compared to normal mammary tissue, invasive ductal carcinoma (IDC) compared to normal mammary tissue, and DCIS... compared to IDC. (2) BCAR3 is significantly upregulated in triple negative breast cancer and normal tissue; (3) BCAR3 expression shows a modest...expression was seen to be elevated in DCIS samples compared to normal mammary tissue, invasive ductal carcinoma (IDC) compared to normal mammary tissue, and

Development of high flux thermal neutron generator for neutron activation analysis

NASA Astrophysics Data System (ADS)

Vainionpaa, Jaakko H.; Chen, Allan X.; Piestrup, Melvin A.; Gary, Charles K.; Jones, Glenn; Pantell, Richard H.

2015-05-01

The new model DD110MB neutron generator from Adelphi Technology produces thermal (<0.5 eV) neutron flux that is normally achieved in a nuclear reactor or larger accelerator based systems. Thermal neutron fluxes of 3-5 · 107 n/cm2/s are measured. This flux is achieved using four ion beams arranged concentrically around a target chamber containing a compact moderator with a central sample cylinder. Fast neutron yield of ∼2 · 1010 n/s is created at the titanium surface of the target chamber. The thickness and material of the moderator is selected to maximize the thermal neutron flux at the center. The 2.5 MeV neutrons are quickly thermalized to energies below 0.5 eV and concentrated at the sample cylinder. The maximum flux of thermal neutrons at the target is achieved when approximately half of the neutrons at the sample area are thermalized. In this paper we present simulation results used to characterize performance of the neutron generator. The neutron flux can be used for neutron activation analysis (NAA) prompt gamma neutron activation analysis (PGNAA) for determining the concentrations of elements in many materials. Another envisioned use of the generator is production of radioactive isotopes. DD110MB is small enough for modest-sized laboratories and universities. Compared to nuclear reactors the DD110MB produces comparable thermal flux but provides reduced administrative and safety requirements and it can be run in pulsed mode, which is beneficial in many neutron activation techniques.

Projections of the Size and Composition of the U.S. Population: 2014 to 2060. Population Estimates and Projections. Current Population Reports. P25-1143

ERIC Educational Resources Information Center

Colby, Sandra L.; Ortman, Jennifer M.

2015-01-01

Between 2014 and 2060, the U.S. population is projected to increase from 319 million to 417 million, reaching 400 million in 2051. The U.S. population is projected to grow more slowly in future decades than in the recent past, as these projections assume that fertility rates will continue to decline and that there will be a modest decline in the…

Beam Width Robustness of a 670 GHz Imaging Radar

NASA Technical Reports Server (NTRS)

Cooper, K. B.; Llombart, N.; Dengler, R. J.; Siegel, P. H.

2009-01-01

Detection of a replica bomb belt concealed on a mannequin at 4 m standoff range is achieved using a 670 GHz imaging radar. At a somewhat larger standoff range of 4.6 m, the radar's beam width increases substantially, but the through-shirt image quality remains good. This suggests that a relatively modest increase in aperture size over the current design will be sufficient to detect person-borne concealed weapons at ranges exceeding 25 meters.

Does Racial Isolation in School Lead to Long-Term Disadvantages? Labor Market Consequences of High School Racial Composition.

PubMed

Gamoran, Adam; Barfels, Sarah; Collares, Ana Cristina

2016-01-01

School racial composition has modest effects on test score gaps, but evidence of a longer-term impact is scarce. Perpetuation theory suggests that blacks who attend schools with higher proportions of white classmates may have better job outcomes. Multilevel analyses of two national longitudinal surveys reveal no effects of high school racial composition on occupational status, employment, or annual earnings for blacks or whites. For other minority groups, attending schools with more whites impedes occupational advancement. For all groups, however, school racial composition predicts workplace racial composition: Whites who attend high schools with higher proportions of white students have higher proportions of white coworkers, while nonwhites who attend schools with higher proportions of whites have fewer same-race coworkers. The findings are modest in size but robust to alternative specifications, and sensitivity analyses support a causal interpretation for same-race coworkers. These results support perpetuation theory for workplace composition but not for stratification outcomes.

Evidence for Anti-Aging South Korean Cosmeceuticals.

PubMed

Quay, Ellinor R; Chang, Yunyoung C; Graber, Emmy

2017-04-01

As the market for South Korean skin care products grows in the U.S. and worldwide, consumers will increasingly seek advice from dermatologists regarding their efficacy. In this paper, the evidence behind the anti-aging and skin whitening activity of ingredients in the most popular South Korean skin care products was reviewed and critically evaluated. Industry profit data from Euromonitor was obtained to identify the top cosmeceutical brands by retail value in South Korea. The top selling products and their ingredients were then identified from individual brand websites. A comprehensive literature search was conducted using Pubmed to identify and grade the anti-aging and whitening efficacy for nine popular ingredients: licorice, niacinamide, beta-glucan, snail mucus, ginkgo biloba, ginseng, green tea, pomegranate, and soy. Of the various ingredients reviewed, niacinamide, green tea, licorice, and soy have the most published data for anti-aging and whitening activity. Although the literature shows modest results, small sample sizes limit interpretation. High-level evidence to support the use of South Korean skin care products in anti-aging and skin whitening is lacking.

J Drugs Dermatol. 2017;16(4):358-364.

Entering the Pantheon of 21st Century Molecular Biology Tools: A Perspective on Digital PCR.

PubMed

Karlin-Neumann, George; Bizouarn, Francisco

2018-01-01

After several decades of relatively modest use, in the last several years digital PCR (dPCR) has grown to become the new gold standard for nucleic acid quantification. This coincides with the commercial availability of scalable, affordable, and reproducible droplet-based dPCR platforms in the past five years and has led to its rapid dissemination into diverse research fields and testing applications. Among these, it has been adopted most vigorously into clinical oncology where it is beginning to be used for plasma genotyping in cancer patients undergoing treatment. Additionally, innovation across the scientific community has extended the benefits of reaction partitioning beyond DNA and RNA quantification alone, and demonstrated its usefulness in evaluating DNA size and integrity, the physical linkage of colocalized markers, levels of enzyme activity and specific cation concentrations in a sample, and more. As dPCR technology gains in popularity and breadth, its power and simplicity can often be taken for granted; thus, the reader is reminded that due diligence must be exercised in order to make claims not only of precision but also of accuracy in their measurements.

Association of testosterone levels and future suicide attempts in females with bipolar disorder

PubMed Central

Sher, Leo; Grunebaum, Michael F.; Sullivan, Gregory M.; Burke, Ainsley K.; Cooper, Thomas B.; Mann, J. John; Oquendo, Maria A.

2015-01-01

Background Considerable evidence suggests that testosterone may play a role in the pathophysiology of mood disorders in females. This is the first prospective study to examine whether blood testosterone levels predict suicide attempts in females with bipolar disorder. Methods Females with a DSM-IV diagnosis of a bipolar disorder in a depressive or mixed episode with at least one past suicide attempt were enrolled. Demographic and clinical parameters were assessed and recorded. Plasma testosterone was assayed using a double antibody radioimmunoassay procedure. Patients were followed up prospectively for up to 2.5 years. Results At baseline, testosterone levels positively correlated with the number of previous major depressive episodes and suicide attempts. Cox proportional hazards regression analysis found that higher baseline testosterone levels predicted suicide attempts during the follow-up period. Limitations A limitation of the study is that the sample size is modest. Another limitation is that we did not have a bipolar nonattempter or healthy volunteer control group for comparison. Conclusion Testosterone levels may predict suicidal behavior in women with bipolar disorder. PMID:25012416

Associations of the vaginal microbiota with HIV infection, bacterial vaginosis, and demographic factors.

PubMed

Chehoud, Christel; Stieh, Daniel J; Bailey, Aubrey G; Laughlin, Alice L; Allen, Shannon A; McCotter, Kerrie L; Sherrill-Mix, Scott A; Hope, Thomas J; Bushman, Frederic D

2017-04-24

We sought to investigate the effects of HIV infection on the vaginal microbiota and associations with treatment and demographic factors. We thus compared vaginal microbiome samples from HIV-infected (HIV+) and HIV-uninfected (HIV-) women collected at two Chicago area hospitals. We studied vaginal microbiome samples from 178 women analyzed longitudinally (n = 324 samples) and collected extensive data on clinical status and demographic factors. We used 16S rRNA gene sequencing to characterize the bacterial lineages present, then UniFrac, Shannon diversity, and other measures to compare community structure with sample metadata. Differences in microbiota measures were modest in the comparison of HIV+ and HIV- samples, in contrast to several previous studies, consistent with effective antiretroviral therapy. Proportions of healthy Lactobacillus species were not higher in HIV- patients overall, but were significantly higher when analyzed within each hospital in isolation. Rates of bacterial vaginosis were higher among African-American women and HIV+ women. Bacterial vaginosis was associated with higher frequency of HIV+. Unexpectedly, African-American women were more likely to switch bacterial vaginosis status between sampling times; switching was not associated with HIV+ status. The influence of HIV infection on the vaginal microbiome was modest for this cohort of well suppressed urban American women, consistent with effective antiretroviral therapy. HIV+ was found to be associated with bacterial vaginosis. Although bacterial vaginosis has previously been associated with HIV transmission, most of the women studied here became HIV+ many years before our test for bacterial vaginosis, thus implicating additional mechanisms linking HIV infection and bacterial vaginosis.

Daily Variation in Adolescents' Sleep, Activities, and Psychological Well-Being

ERIC Educational Resources Information Center

Fuligni, Andrew J.; Hardway, Christina

2006-01-01

The daily diary method was used to examine the daily dynamics of adolescent sleep time, activities, and psychological well-being among an ethnically diverse sample of over 750 adolescents approximately 14-15 years of age. Studying and stressful demands during the day were modestly but consistently associated with less sleep that evening. Receiving…

Debunking Anti-Intellectualism: An Examination of African American College Students' Intellectual Self-Concepts

ERIC Educational Resources Information Center

Cole, Darnell

2011-01-01

Framed within the debate on African American "anti-intellectualism," this study examined a longitudinal sample of 460 African American students' intellectual self-concept and college grades (GPA) through regression analyses resulting from their college experiences. The findings showed that the college environment had a modest influence on African…

Family, Religiosity, and the Risk of Adolescent Drug Use.

ERIC Educational Resources Information Center

Bahr, Stephen J.; Maughan, Suzanne L.; Marcos, Anastasios C.; Li, Bingdao

1998-01-01

Uses data from a random sample of 13,250 adolescents. Results show that mother/adolescent bonding and family drug problems have modest, indirect effects on the likelihood of adolescent drug use; father/adolescent bonding, parental monitoring, and family aggression have relatively weak effects on adolescent drug use; and religious students do not…

Reports of severe physical punishment and exposure to animal cruelty by inmates convicted of felonies and by university students.

PubMed

Miller, K S; Knutson, J F

1997-01-01

A self-report questionnaire designed to assess abusive childhood environments and exposure to animal cruelty was administered to 314 inmates in a prisoner classification center. Although high rates of physical punishment characterized the entire sample, persons charged with violent, but nonhomicidal crimes reported more severely punitive childhood histories than those charged with homicidal crimes, sex offenses, and nonviolent offenses. Some exposure to animal cruelty was widespread in the sample, but there was no association between experiencing animal cruelty and the type of crime committed. Moreover, there were only modest associations between animal cruelty experiences and the aversive childhood histories of the subjects, as well as the subjects' reported use of physical and sexual coercion in dating and intimate relationships. To determine whether the high base rate of exposure to animal cruelty was unique to the incarcerated sample, a follow-up study was completed with university undergraduates. Widespread exposure to some animal cruelty was reported by undergraduates; there were modest associations between reporting animal cruelty and reporting punitive and acrimonious childhood histories. In general, the findings were consistent with the hypothesis that there is an association between punitive childhood histories and antisocial behavior but not consistent with the hypothesis that exposure to animal cruelty is importantly related to antisocial behavior or child maltreatment.

g in Middle Childhood: Moderate Genetic and Shared Environmental Influence Using Diverse Measures of General Cognitive Ability at 7, 9 and 10 Years in a Large Population Sample of Twins

ERIC Educational Resources Information Center

Davis, Oliver S. P.; Arden, Rosalind; Plomin, Robert

2008-01-01

A 2003 paper in this journal reported results from a large sample of twins assessed at 2, 3 and 4 years of age on parent-administered tests and reports of their verbal and nonverbal ability. We found clear evidence for phenotypic general cognitive ability (g) that accounted for about 50% of the variance, for modest genetic influence on g (about…

Alterations in welding process voltage affect the generation of ultrafine particles, fume composition, and pulmonary toxicity.

PubMed

Antonini, James M; Keane, Michael; Chen, Bean T; Stone, Samuel; Roberts, Jenny R; Schwegler-Berry, Diane; Andrews, Ronnee N; Frazer, David G; Sriram, Krishnan

2011-12-01

The goal was to determine if increasing welding voltage changes the physico-chemical properties of the fume and influences lung responses. Rats inhaled 40 mg/m³ (3 h/day × 3 days) of stainless steel (SS) welding fume generated at a standard voltage setting of 25 V (regular SS) or at a higher voltage (high voltage SS) of 30 V. Particle morphology, size and composition were characterized. Bronchoalveolar lavage was performed at different times after exposures to assess lung injury. Fumes collected from either of the welding conditions appeared as chain-like agglomerates of nanometer-sized primary particles. High voltage SS welding produced a greater number of ultrafine-sized particles. Fume generated by high voltage SS welding was higher in manganese. Pulmonary toxicity was more substantial and persisted longer after exposure to the regular SS fume. In summary, a modest raise in welding voltage affected fume size and elemental composition and altered the temporal lung toxicity profile.

Design of pilot studies to inform the construction of composite outcome measures.

PubMed

Edland, Steven D; Ard, M Colin; Li, Weiwei; Jiang, Lingjing

2017-06-01

Composite scales have recently been proposed as outcome measures for clinical trials. For example, the Prodromal Alzheimer's Cognitive Composite (PACC) is the sum of z-score normed component measures assessing episodic memory, timed executive function, and global cognition. Alternative methods of calculating composite total scores using the weighted sum of the component measures that maximize signal-to-noise of the resulting composite score have been proposed. Optimal weights can be estimated from pilot data, but it is an open question how large a pilot trial is required to calculate reliably optimal weights. In this manuscript, we describe the calculation of optimal weights, and use large-scale computer simulations to investigate the question of how large a pilot study sample is required to inform the calculation of optimal weights. The simulations are informed by the pattern of decline observed in cognitively normal subjects enrolled in the Alzheimer's Disease Cooperative Study (ADCS) Prevention Instrument cohort study, restricting to n=75 subjects age 75 and over with an ApoE E4 risk allele and therefore likely to have an underlying Alzheimer neurodegenerative process. In the context of secondary prevention trials in Alzheimer's disease, and using the components of the PACC, we found that pilot studies as small as 100 are sufficient to meaningfully inform weighting parameters. Regardless of the pilot study sample size used to inform weights, the optimally weighted PACC consistently outperformed the standard PACC in terms of statistical power to detect treatment effects in a clinical trial. Pilot studies of size 300 produced weights that achieved near-optimal statistical power, and reduced required sample size relative to the standard PACC by more than half. These simulations suggest that modestly sized pilot studies, comparable to that of a phase 2 clinical trial, are sufficient to inform the construction of composite outcome measures. Although these findings apply only to the PACC in the context of prodromal AD, the observation that weights only have to approximate the optimal weights to achieve near-optimal performance should generalize. Performing a pilot study or phase 2 trial to inform the weighting of proposed composite outcome measures is highly cost-effective. The net effect of more efficient outcome measures is that smaller trials will be required to test novel treatments. Alternatively, second generation trials can use prior clinical trial data to inform weighting, so that greater efficiency can be achieved as we move forward.

Set-Membership Identification for Robust Control Design

DTIC Science & Technology

1993-04-28

system G can be regarded as having no memory in (18) in terms of G and 0, we get of events prior to t = 1, the initial time. Roughly, this means all...algorithm in [1]. Also in our application, the size of the matrices involved is quite large and special attention should be paid to the memory ...management and algorithmic implementation; otherwise huge amounts of memory will be required to perform the optimization even for modest values of M and N

Model studies of laser absorption computed tomography for remote air pollution measurement

NASA Technical Reports Server (NTRS)

Wolfe, D. C., Jr.; Byer, R. L.

1982-01-01

Model studies of the potential of laser absorption-computed tomography are presented which demonstrate the possibility of sensitive remote atmospheric pollutant measurements, over kilometer-sized areas, with two-dimensional resolution, at modest laser source powers. An analysis of this tomographic reconstruction process as a function of measurement SNR, laser power, range, and system geometry, shows that the system is able to yield two-dimensional maps of pollutant concentrations at ranges and resolutions superior to those attainable with existing, direct-detection laser radars.

Genetics and Genomics of Single-Gene Cardiovascular Diseases: Common Hereditary Cardiomyopathies as Prototypes of Single-Gene Disorders

PubMed Central

Marian, Ali J.; van Rooij, Eva; Roberts, Robert

2016-01-01

This is the first of 2 review papers on genetics and genomics appearing as part of the series on “omics.” Genomics pertains to all components of an organism’s genes, whereas genetics involves analysis of a specific gene(s) in the context of heredity. The paper provides introductory comments, describes the basis of human genetic diversity, and addresses the phenotypic consequences of genetic variants. Rare variants with large effect sizes are responsible for single-gene disorders, whereas complex polygenic diseases are typically due to multiple genetic variants, each exerting a modest effect size. To illustrate the clinical implications of genetic variants with large effect sizes, 3 common forms of hereditary cardiomyopathies are discussed as prototypic examples of single-gene disorders, including their genetics, clinical manifestations, pathogenesis, and treatment. The genetic basis of complex traits is discussed in a separate paper. PMID:28007145

The 4D evolution of porosity during ongoing pressure-solution processes in NaCl using x-ray microtomography

NASA Astrophysics Data System (ADS)

Macente, Alice; Fusseis, Florian; Butler, Ian; Tudisco, Erika; Hall, Stephen; Andò, Edward

2016-04-01

Pressure-solution creep is a common deformation mechanism in the upper crust. It represents a mass transfer via dissolution-reprecipitation that critically affects the hydraulic properties of rocks. Successful management of safe radioactive storage sites in rock-salt deposits critically depends on an accurate knowledge of the hydro-mechanical behaviour of salt deposits. Despite numerous lab experiments that have been conducted, many aspects of pressure-solution are still poorly understood. There is little knowledge about the spatio-temporal evolution of porosity and permeability during pressure-solution creep. While rates of pressure-solution creep in silicates and carbonates are slow, which makes laboratory investigations of these materials impractical, compaction experiments have demonstrated that NaCl samples deform sufficiently fast to study pressure-solution creep in a lab environment at room temperature and modest loads. We present results from novel experiments that quantify the 4-dimensional (three spatial dimensions plus time) evolution of pressure-solution processes using in-situ x-ray microtomography. Our experiments are performed in custom made x-ray transparent presses. 5 mm diameter NaCl powder samples with a grain size of 250-300 μm are loaded dry into the press and pre-compacted to produce a starting aggregated material. The sample is then flooded with saturated NaCl solution and loaded uniaxially by means of a pneumatic actuator to a constant uniaxial stress. Different sample mixtures were tested, as well as different uniaxial loads. The resulting deformation of the samples is documented in 3-dimensional microtomographic datasets, acquired at regular time intervals. Image analysis allowed characterization of the microstructural evolution of the NaCl grains and the spatio-temporal distribution of porosity during ongoing mechanical and chemical compaction. The microtomography data have also been analysed with 3D Digital Image Correlation (3D-DIC or DVC) to quantify the fields of displacements in each direction, as well as volumetric and maximum shear strain fields. Following the approach described above, we have been able to quantify and characterize in 4D the evolution of pressure-solution creep and porosity distribution in relation to different sample materials and increasing uniaxial load. The presence of phyllosilicates (biotite) and more competent materials (glass beads) allowed pressure-solution to develop in a much shorter time compared to pure halite sample. The same trend is observed in samples experiencing bigger uniaxial loads (6.6 MPa v 1.6 MPa). We also found that, in the presence of phyllosilicates (biotite), pore size distribution clearly reflects the localisation of pressure-solution processes, as for natural stylolites. In the presence of glass beads, pressure-solution has a greater effect on the pore orientations rather than pore sizes. Our results extend the current understanding of the effect of pressure-solution creep on the mechanical and hydraulic properties of rocks, with implications for natural rock-salt, salt-based repository systems (nuclear and chemical waste storage) and salt mining.

Healthy Aging: Is Smaller Better?

PubMed Central

Bartke, Andrzej

2014-01-01

A recent report of virtually complete protection from diabetes and cancer in a population of people with hereditary dwarfism revived interest in elucidating the relationships between growth, adult body size, age-related disease and longevity. In many species, smaller individuals outlive those that are larger and a similar relationship was shown in studies of various human populations. Adult body size is strongly dependent on the actions of growth hormone (GH) and the absence of GH or GH receptor in mice leads to a remarkable extension of longevity. Many mechanisms that may account for, or contribute to, this association have been identified. It is suggested that modest modifications of the diet at different ages may extend human healthspan and lifespan by reducing levels of hormones that stimulate growth. PMID:22261798

Single-axis four-mirror system: large spherical primary and small fields

NASA Astrophysics Data System (ADS)

Baranne, Andre

1998-08-01

A catoptric corrector of modest size can be used for large spherical primaries, easily integrated at the prime focus, this corrector gives back to the system, aspect and properties of 2-mirrors classical telescopes. In the last few years, progress in active and adaptative optics makes possible a lot of things, progress in measuring distances, new ideas on optical coatings, new materials and so on in a near future, all that makes the instrumentalist dreamy It is said that nobody knows today if the size of 3rd millennium telescopes will be limited or not by a theoretical, physical or technical phenomenon, thus let us imagine but with thoughtfulness because our projects will be surely restricted by financial considerations

GEO Population Estimates using Optical Survey Data

NASA Technical Reports Server (NTRS)

Barker, Edwin S.; Matney, Mark J.

2007-01-01

Optical survey data taken using the NASA Michigan Orbital Debris Survey Telescope (MODEST) gives us an opportunity to statistically sample faint object population in the Geosynchronous (GEO) and near-GEO environment. This paper will summarize the MODEST survey work that has been conducted by NASA since 2002, and will outline the techniques employed to arrive at the current population estimates in the GEO environment for dim objects difficult to detect and track using current systems in the Space Surveillance Network (SSN). Some types of orbits have a higher detection rate based on what parts of the GEO belt is being observed, a straightforward statistical technique is used to debias these observations to arrive at an estimate of the total population potentially visible to the telescope. The size and magnitude distributions of these fainter debris objects are markedly different from the catalogued population. GEO debris consists of at least two different populations, one which follows the standard breakup power law and one which has anomalously high Area-to-Mass Ratios (1 to approx. 30 square meters per kilogram; a sheet of paper = approx. 13 square meters per kilogram). The Inter-Agency Space Debris Coordination Committee (IADC) is investigating objects in GEO orbits with anomalously high Area-to-Mass Ratios (AMRs). The ESA Space Debris Telescope discovered this population and has and its properties of inclinations (0 to 30 degrees), changing eccentricities (0 and 0.6), and mean motions (approx. 1 rev), will be presented. The accepted interpretation of this orbital behavior is that solar radiation pressure drives the perturbations causing time varying inclinations and eccentricities. The orbital parameters are unstable for this population and thus difficult to predict. Their dim visual magnitudes and photometric variability make observations a challenge. The IADC has enlisted a series of observatories (participating institutions: University of Michigan/CTIO, Astronomical Institute University of Bern, Boeing LTS / AMOS, Keldysh Institute of Applied Mathematics) at different longitudes. Complete observational coverage over periods of days to months will provide a better understanding of the properties, such as solar radiation pressure effects on orbital elements, size, shape, attitude, color variations, and spectral characteristics. Results from recent observational programs will be summarized, and includes a description of the orbit elements prediction processes, a summary of the metric tracking performance, and some photometric characteristics of this class of debris.

The impact of a large-scale quality improvement programme on work engagement: preliminary results from a national cross-sectional-survey of the 'Productive Ward'.

PubMed

White, Mark; Wells, John S G; Butterworth, Tony

2014-12-01

Quality improvement (QI) Programmes, like the Productive Ward: Releasing-time-to-care initiative, aim to 'engage' and 'empower' ward teams to actively participate, innovate and lead quality improvement at the front line. However, little is known about the relationship and impact that QI work has on the 'engagement' of the clinical teams who participate and vice-versa. This paper explores and examines the impact of a large-scale QI programme, the Productive Ward, on the 'work engagement' of the nurses and ward teams involved. Using the Utrecht Work Engagement Scale (UWES), we surveyed, measured and analysed work engagement in a representative test group of hospital-based ward teams who had recently commenced the latest phase of the national 'Productive Ward' initiative in Ireland and compared them to a control group of similar size and matched (as far as is possible) on variables such as ward size, employment grade and clinical specialty area. 338 individual datasets were recorded, n=180 (53.6%) from the Productive Ward group, and n=158 (46.4%) from the control group; the overall response rate was 67%, and did not differ significantly between the Productive Ward and control groups. The work engagement mean score (±standard deviation) in the Productive group was 4.33(±0.88), and 4.07(±1.06) in the control group, representing a modest but statistically significant between-group difference (p=0.013, independent samples t-test). Similarly modest differences were observed in all three dimensions of the work engagement construct. Employment grade and the clinical specialty area were also significantly related to the work engagement score (p<0.001, general linear model) and (for the most part), to its components, with both clerical and nurse manager grades, and the elderly specialist areas, exhibiting substantially higher scores. The findings demonstrate how QI activities, like those integral to the Productive Ward programme, appear to positively impact on the work engagement (the vigour, absorption and dedication) of ward-based teams. The use and suitability of the UWES as an appropriate measure of 'engagement' in QI interventions was confirmed. The engagement of nurses and front-line clinical teams is a major component of creating, developing and sustaining a culture of improvement. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

College Writing in China and America: A Modest and Humble Conversation, with Writing Samples

ERIC Educational Resources Information Center

Sullivan, Patrick; Zhang, Yufeng; Zheng, Fenglan

2012-01-01

This article is a pragmatic, classroom-focused conversation about the teaching of writing among three teachers living in the United States and China, separated by many thousands of miles and many centuries of tradition and culture. Our focus here is on classroom concerns: actual student writing, assignment design, and assessment. We seek to…

Unvorgreifliche Gedanken, betreffend die Ausuebung und Verbesserung des Uebersetzungsunterrichts Englisch-Deutsch. (Modest Thoughts on the Use and Improvement of Training in Translation -- English to German).

ERIC Educational Resources Information Center

Haber, Bernd K.

1978-01-01

Surveys current practice in teaching translation and finds it faulty. An almost mathematical model of translation strategy is suggested for upper-level students of English who can use a monolingual dictionary. Two sample texts for testing the model are appended. (IFS/WGA)

A Twin and Adoption Study of Reading Achievement: Exploration of Shared-Environmental and Gene-Environment-Interaction Effects

ERIC Educational Resources Information Center

Kirkpatrick, Robert M.; Legrand, Lisa N.; Iacono, William G.; McGue, Matt

2011-01-01

Existing behavior-genetic research implicates substantial influence of heredity and modest influence of shared environment on reading achievement and reading disability. Applying DeFries-Fulker analysis to a combined sample of twins and adoptees (N = 4886, including 266 reading-disabled probands), the present study replicates prior findings of…

Effects of a group-focused cognitive behavioral health education program on cigarette smoking in a sample of Nigerian prisoners

PubMed Central

Onyechi, Kay C.N.; Eseadi, Chiedu; Umoke, Prince C.I.; Ikechukwu-Ilomuanya, Amaka B.; Otu, Mkpoikanke S.; Obidoa, Jaachimma C.; Agu, Fedinand U.; Nwaubani, Okechukwu O.; Utoh-Ofong, Anthonia N.; Ncheke, Chijioke D.; Ugwuozor, Felix O.

2017-01-01

Abstract Background: Smoking is a learned habit that has an impact on the psychological and biochemical health of individuals. It is the leading preventable cause of chronic illness worldwide. The purpose of this study was to examine the effects of a group-focused cognitive behavioral health education program (GCBHEP) on cigarette smoking in a sample of Nigerian prisoners. Methods: The study used a pretest–posttest randomized control group design. Twenty inmates were identified through self-reporting, 1-to-1 counseling, and observation. The treatment group took part in a GCBHEP for 10 weeks, while the control group received 10 weeks’ conventional counseling. After the intervention program, both the treatment and control groups were evaluated. The repeated measures analysis of variance was used for data analysis and partial η2 was also used as a measure of effect size. Results: The findings showed that the GCBHEP had a strong effect on cigarette-smoking habits among the inmates in the treatment group compared with those in the control group. The effect of the GCBHEP by age was moderate, and modest by educational qualification. Conclusion: Group-focused cognitive behavioral health education is effective in breaking the habit of cigarette smoking among Nigerian prisoners. Therefore, future researchers are encouraged to adopt this approach in helping individuals with a smoking problem and other drug-abuse behaviors in Nigerian prisons. PMID:28072681

Effects of a group-focused cognitive behavioral health education program on cigarette smoking in a sample of Nigerian prisoners.

PubMed

Onyechi, Kay C N; Eseadi, Chiedu; Umoke, Prince C I; Ikechukwu-Ilomuanya, Amaka B; Otu, Mkpoikanke S; Obidoa, Jaachimma C; Agu, Fedinand U; Nwaubani, Okechukwu O; Utoh-Ofong, Anthonia N; Ncheke, Chijioke D; Ugwuozor, Felix O

2017-01-01

Smoking is a learned habit that has an impact on the psychological and biochemical health of individuals. It is the leading preventable cause of chronic illness worldwide. The purpose of this study was to examine the effects of a group-focused cognitive behavioral health education program (GCBHEP) on cigarette smoking in a sample of Nigerian prisoners. The study used a pretest-posttest randomized control group design. Twenty inmates were identified through self-reporting, 1-to-1 counseling, and observation. The treatment group took part in a GCBHEP for 10 weeks, while the control group received 10 weeks' conventional counseling. After the intervention program, both the treatment and control groups were evaluated. The repeated measures analysis of variance was used for data analysis and partial η was also used as a measure of effect size. The findings showed that the GCBHEP had a strong effect on cigarette-smoking habits among the inmates in the treatment group compared with those in the control group. The effect of the GCBHEP by age was moderate, and modest by educational qualification. Group-focused cognitive behavioral health education is effective in breaking the habit of cigarette smoking among Nigerian prisoners. Therefore, future researchers are encouraged to adopt this approach in helping individuals with a smoking problem and other drug-abuse behaviors in Nigerian prisons.

Investigating the Relationship between Stable Personality Characteristics and Automatic Imitation

PubMed Central

Butler, Emily E.; Ward, Robert; Ramsey, Richard

2015-01-01

Automatic imitation is a cornerstone of nonverbal communication that fosters rapport between interaction partners. Recent research has suggested that stable dimensions of personality are antecedents to automatic imitation, but the empirical evidence linking imitation with personality traits is restricted to a few studies with modest sample sizes. Additionally, atypical imitation has been documented in autism spectrum disorders and schizophrenia, but the mechanisms underpinning these behavioural profiles remain unclear. Using a larger sample than prior studies (N=243), the current study tested whether performance on a computer-based automatic imitation task could be predicted by personality traits associated with social behaviour (extraversion and agreeableness) and with disorders of social cognition (autistic-like and schizotypal traits). Further personality traits (narcissism and empathy) were assessed in a subsample of participants (N=57). Multiple regression analyses showed that personality measures did not predict automatic imitation. In addition, using a similar analytical approach to prior studies, no differences in imitation performance emerged when only the highest and lowest 20 participants on each trait variable were compared. These data weaken support for the view that stable personality traits are antecedents to automatic imitation and that neural mechanisms thought to support automatic imitation, such as the mirror neuron system, are dysfunctional in autism spectrum disorders or schizophrenia. In sum, the impact that personality variables have on automatic imitation is less universal than initial reports suggest. PMID:26079137

Investigating the Relationship between Stable Personality Characteristics and Automatic Imitation.

PubMed

Butler, Emily E; Ward, Robert; Ramsey, Richard

2015-01-01

Automatic imitation is a cornerstone of nonverbal communication that fosters rapport between interaction partners. Recent research has suggested that stable dimensions of personality are antecedents to automatic imitation, but the empirical evidence linking imitation with personality traits is restricted to a few studies with modest sample sizes. Additionally, atypical imitation has been documented in autism spectrum disorders and schizophrenia, but the mechanisms underpinning these behavioural profiles remain unclear. Using a larger sample than prior studies (N=243), the current study tested whether performance on a computer-based automatic imitation task could be predicted by personality traits associated with social behaviour (extraversion and agreeableness) and with disorders of social cognition (autistic-like and schizotypal traits). Further personality traits (narcissism and empathy) were assessed in a subsample of participants (N=57). Multiple regression analyses showed that personality measures did not predict automatic imitation. In addition, using a similar analytical approach to prior studies, no differences in imitation performance emerged when only the highest and lowest 20 participants on each trait variable were compared. These data weaken support for the view that stable personality traits are antecedents to automatic imitation and that neural mechanisms thought to support automatic imitation, such as the mirror neuron system, are dysfunctional in autism spectrum disorders or schizophrenia. In sum, the impact that personality variables have on automatic imitation is less universal than initial reports suggest.

Sensitivity to sequencing depth in single-cell cancer genomics.

PubMed

Alves, João M; Posada, David

2018-04-16

Querying cancer genomes at single-cell resolution is expected to provide a powerful framework to understand in detail the dynamics of cancer evolution. However, given the high costs currently associated with single-cell sequencing, together with the inevitable technical noise arising from single-cell genome amplification, cost-effective strategies that maximize the quality of single-cell data are critically needed. Taking advantage of previously published single-cell whole-genome and whole-exome cancer datasets, we studied the impact of sequencing depth and sampling effort towards single-cell variant detection. Five single-cell whole-genome and whole-exome cancer datasets were independently downscaled to 25, 10, 5, and 1× sequencing depth. For each depth level, ten technical replicates were generated, resulting in a total of 6280 single-cell BAM files. The sensitivity of variant detection, including structural and driver mutations, genotyping, clonal inference, and phylogenetic reconstruction to sequencing depth was evaluated using recent tools specifically designed for single-cell data. Altogether, our results suggest that for relatively large sample sizes (25 or more cells) sequencing single tumor cells at depths > 5× does not drastically improve somatic variant discovery, characterization of clonal genotypes, or estimation of single-cell phylogenies. We suggest that sequencing multiple individual tumor cells at a modest depth represents an effective alternative to explore the mutational landscape and clonal evolutionary patterns of cancer genomes.

Attrition factors in clinical trials of comorbid bipolar and substance-related disorders.

PubMed

Nomamiukor, Nicole; Brown, E Sherwood

2009-01-01

This study analyzed and defined specific factors that account for attrition in clinical research for patients with bipolar and substance-related disorders. Data were analyzed from two completed studies: an open-label trial of lamotrigine in patients with bipolar disorder (BPD) and cocaine-related disorder, and a placebo-controlled trial of quetiapine in patients with BPD and alcohol-related disorders. Correlations and Independent sample t-tests were performed to assess the impact of baseline characteristics including on length of study participation. Significance was set at the p=0.05 level. In the lamotrigine-treated patients, the presence of an amphetamine-related disorder, in addition to cocaine-related disorders, was associated with a shorter time in the study. In the quetiapine-treated patients higher scores on the Addiction Severity Index Legal subscale were associated with shorter length in the study. The presence of panic disorder was associated with shorter time in both studies. Although the data were taken from the two largest clinical trials, to date, in patients with BPD and substance-related disorders, the sample sizes were relatively modest. In addition, the baseline assessments were somewhat different in the two studies limiting our ability to make conclusions on differences between patients with BPD and cocaine use versus alcohol use. This study adds to an emerging literature on the significance of panic disorder in patients with BPD.

Using smartphone video “selfies” to monitor change in toothbrushing behavior after a brief intervention: A pilot study

PubMed Central

Kumar, Parangimalai Diwakar Madan; Mohandoss, Anusa Arunachalam; Walls, Theodore; Rooban, Thavarajah; Vernon, Lance T

2018-01-01

Background Attempts to refine toothbrushing (TB) technique, an ingrained habit in adults, can meet with some challenges. Recently, the role of proactive interference as a barrier to improving the learning of proper brushing has been proposed. This pilot feasibility study was designed to investigate TB behavior and to see how it changes after training. Smartphone video “selfies” (SPVSs) are increasingly being used in the medical field to assess, monitor, and determine the progression of diseases. Materials and Methods We used SPVS to study TB skills in a small sample of volunteers. Over a period of 14 days, after a one-time group training session, we observed TB behavior of volunteers using self-captured SPVS. Results Following the brief intervention, we observed an 8% of improvement in TB skills. Discussion To the best of our knowledge, this is the first report using SPVS to study TB behavior. We demonstrated initial feasibility of using SPVS in the dental setting. We observed modest improvements in toothbrushing accuracy and quality, and we generated important experiences about the use of Selfies for TB monitoring and intervention, and some interesting insights about where in the toothbrushing is more or less effective. Conclusion Further investigation using a larger sample size is needed to thoroughly assess the effectiveness of this approach to improve TB skills and better understand the role of proactive interference. PMID:27411655

Survey of the Heritability and Sparse Architecture of Gene Expression Traits across Human Tissues.

PubMed

Wheeler, Heather E; Shah, Kaanan P; Brenner, Jonathon; Garcia, Tzintzuni; Aquino-Michaels, Keston; Cox, Nancy J; Nicolae, Dan L; Im, Hae Kyung

2016-11-01

Understanding the genetic architecture of gene expression traits is key to elucidating the underlying mechanisms of complex traits. Here, for the first time, we perform a systematic survey of the heritability and the distribution of effect sizes across all representative tissues in the human body. We find that local h2 can be relatively well characterized with 59% of expressed genes showing significant h2 (FDR < 0.1) in the DGN whole blood cohort. However, current sample sizes (n ≤ 922) do not allow us to compute distal h2. Bayesian Sparse Linear Mixed Model (BSLMM) analysis provides strong evidence that the genetic contribution to local expression traits is dominated by a handful of genetic variants rather than by the collective contribution of a large number of variants each of modest size. In other words, the local architecture of gene expression traits is sparse rather than polygenic across all 40 tissues (from DGN and GTEx) examined. This result is confirmed by the sparsity of optimal performing gene expression predictors via elastic net modeling. To further explore the tissue context specificity, we decompose the expression traits into cross-tissue and tissue-specific components using a novel Orthogonal Tissue Decomposition (OTD) approach. Through a series of simulations we show that the cross-tissue and tissue-specific components are identifiable via OTD. Heritability and sparsity estimates of these derived expression phenotypes show similar characteristics to the original traits. Consistent properties relative to prior GTEx multi-tissue analysis results suggest that these traits reflect the expected biology. Finally, we apply this knowledge to develop prediction models of gene expression traits for all tissues. The prediction models, heritability, and prediction performance R2 for original and decomposed expression phenotypes are made publicly available (https://github.com/hakyimlab/PrediXcan).

Mini-Spec: A Compact, Fiber-Coupled, VPH Grating Spectrograph for Small Observatories

NASA Astrophysics Data System (ADS)

Nations, H. L.; Haynes, P.; Brewer, P.

2003-05-01

We report on the development and testing of what we believe to be the first VPH grating based spectrograph developed primarily for use at telescopes of modest aperture. To date, the most common instrument suite for such observatories is typically that of a CCD camera with attached filter wheel. While there is no doubt that a wide range of interesting and good science has been done with such instrumentation, the addition of a robust and easy to operate spectrograph would greatly increase the utility of such installations. While some commercial spectrographs exist for use on small telescopes, the authors have found them to be, with few exceptions, either inefficient, difficult for inexperienced students or amateurs to use, or not remotely operable. Correcting these deficiencies is thus the primary motivation for Mini-Spec. The design of Mini-Spec has been influenced by previous work the authors have done on a full-sized fiber-coupled spectrograph (Nations and Pierce, 2002). Mini-Spec uses some of those original design features, only reduced drastically in size. This size reduction (the spectrograph fits within a 7 inch cube), along with a much more careful choice of some critical components, has resulted in a dramatic reduction in cost. The spectrograph uses a highly efficient 1200 l/mm, 40 mm diameter vph grating on loan from Richard Rallison. Focus, central wavelength selection, and comparison lamps are all controlled via an RS-232 link and a custom Visual Basic GUI. Sample spectra of stellar and non-stellar targets will be presented along with a discussion of research projects admirably suited for this instrument. Funding for equipment has been provided by a NASA EPSCoR grant to PI Ron Canterna. HLN has been partially funded by a Wyoming Space Grant Faculty Fellowship.

Urine and toenail cadmium levels in pregnant women: A reliability study.

PubMed

White, Alexandra J; O'Brien, Katie M; Jackson, Brian P; Karagas, Margaret R

2018-05-29

Cadmium, as measured in human tissue, has been associated with numerous health outcomes. However, few studies have evaluated the reliability of cadmium measurements across different biologic samples. We evaluated toenail cadmium levels over time and compared toenail cadmium to urinary cadmium. We also evaluated the relationship between biomarker concentrations and cigarette smoking, a known source of cadmium exposure. Cadmium was assessed in urine and toenail samples collected from 1338 pregnant women participating in the New Hampshire Birth Cohort Study. Each participant was asked to provide a urine and a toenail sample at enrollment (between 24 and 28 weeks gestation) and another toenail sample 2-8 weeks postpartum. Cadmium concentrations were determined using inductively-coupled plasma mass spectrometry. Spearman correlations were assessed for cadmium in the toenails across the two-time points and comparing toenail and urine levels. Smoking status was evaluated as a predictor of cadmium levels. Toenail cadmium assessed during pregnancy and postpartum were modestly correlated (R = 0.3, p < 0.0001). However, urine and toenail cadmium levels were unrelated (R = -0.03, p = 0.46). Both toenail and urinary cadmium levels were associated with women's smoking status. Our findings suggest that both toenail and urinary cadmium concentrations reflect the major source of exposure - cigarette smoking. Toenail cadmium concentrations are modestly reproducible pre- and postpartum; but do not appear to be related to urinary cadmium and thus likely represent different windows and chronicity of exposure among pregnant women. Published by Elsevier Ltd.

Evaluation of group and self-directed formats of the Arthritis Foundation's Walk With Ease Program.

PubMed

Callahan, Leigh F; Shreffler, Jack H; Altpeter, Mary; Schoster, Britta; Hootman, Jennifer; Houenou, Laura O; Martin, Kathryn R; Schwartz, Todd A

2011-08-01

To evaluate the effects of a revised 6-week walking program for adults with arthritis, Walk With Ease (WWE), delivered in 2 formats, instructor-led group or self-directed. In an observational pre-post study design, 462 individuals with self-reported arthritis selected either a group format (n = 192) or a self-directed (n = 270) format. Performance and self-reported outcomes were assessed at baseline and at 6 weeks. Self-reported outcomes were assessed at 1 year. Adjusted mean outcome values for group and self-directed participants were determined using regression models, adjusting for covariates. At 6 weeks, significant adjusted mean improvements (P < 0.05) were seen for nearly all self-report and performance measures in both formats. Modest to moderate effect sizes (ES) were seen for disability (ES 0.16-0.23), pain, fatigue, and stiffness (ES 0.21-0.40), and helplessness (ES 0.24-0.28). The Arthritis Self-Efficacy (ASE) pain and symptom scales had modest improvements (ES 0.09-0.21). The performance measures of strength (ES 0.29-0.35), balance (ES 0.12-0.36), and walking pace (ES 0.12-0.32) all showed modest to moderate improvements. No adverse events were reported for either format. At 1 year, both formats showed modest improvement in ASE pain, but there were 5 outcomes where self-directed participants showed significant improvement, while the group participants did not. The revised WWE program decreases disability and improves arthritis symptoms, self-efficacy, and perceived control, balance, strength, and walking pace in individuals with arthritis, regardless of whether they are taking a group class or doing the program as self-directed walkers. At 1 year, some benefits are maintained, particularly among the self-directed. This is a safe, easy, and inexpensive program to promote community-based physical activity. Copyright © 2011 by the American College of Rheumatology.

Meta-analyses of Theory use in Medication Adherence Intervention Research

PubMed Central

Conn, Vicki S.; Enriquez, Maithe; Ruppar, Todd M.; Chan, Keith C.

2016-01-01

Objective This systematic review applied meta-analytic procedures to integrate primary research that examined theory- or model-linked medication adherence interventions. Methods Extensive literature searching strategies were used to locate trials testing interventions with medication adherence behavior outcomes measured by electronic event monitoring, pharmacy refills, pill counts, and self-reports. Random-effects model analysis was used to calculate standardized mean difference effect sizes for medication adherence outcomes. Results Codable data were extracted from 146 comparisons with 19,348 participants. The most common theories and models were social cognitive theory and motivational interviewing. The overall weighted effect size for all interventions comparing treatment and control participants was 0.294. The effect size for interventions based on single-theories was 0.323 and for multiple-theory interventions was 0.214. Effect sizes for individual theories and models ranged from 0.041 to 0.447. The largest effect sizes were for interventions based on the health belief model (0.477) and adult learning theory (0.443). The smallest effect sizes were for interventions based on PRECEDE (0.041) and self-regulation (0.118). Conclusion These findings suggest that theory- and model-linked interventions have a significant but modest effect on medication adherence outcomes. PMID:26931748

Multi-center feasibility study evaluating recruitment, variability in risk factors and biomarkers for a diet and cancer cohort in India

PubMed Central

2011-01-01

Background India's population exhibits diverse dietary habits and chronic disease patterns. Nutritional epidemiologic studies in India are primarily of cross-sectional or case-control design and subject to biases, including differential recall of past diet. The aim of this feasibility study was to evaluate whether a diet-focused cohort study of cancer could be established in India, providing insight into potentially unique diet and lifestyle exposures. Methods Field staff contacted 7,064 households within three regions of India (New Delhi, Mumbai, and Trivandrum) and found 4,671 eligible adults aged 35-69 years. Participants completed interviewer-administered questionnaires (demographic, diet history, physical activity, medical/reproductive history, tobacco/alcohol use, and occupational history), and staff collected biological samples (blood, urine, and toenail clippings), anthropometric measurements (weight, standing and sitting height; waist, hip, and thigh circumference; triceps, sub-scapula and supra-patella skin fold), and blood pressure measurements. Results Eighty-eight percent of eligible subjects completed all questionnaires and 67% provided biological samples. Unique protein sources by region were fish in Trivandrum, dairy in New Delhi, and pulses (legumes) in Mumbai. Consumption of meat, alcohol, fast food, and soft drinks was scarce in all three regions. A large percentage of the participants were centrally obese and had elevated blood glucose levels. New Delhi participants were also the least physically active and had elevated lipids levels, suggesting a high prevalence of metabolic syndrome. Conclusions A high percentage of participants complied with study procedures including biological sample collection. Epidemiologic expertise and sufficient infrastructure exists at these three sites in India to successfully carry out a modest sized population-based study; however, we identified some potential problems in conducting a cohort study, such as limited number of facilities to handle biological samples. PMID:21619649

Testing a level of response to alcohol-based model of heavy drinking and alcohol problems in 1,905 17-year-olds.

PubMed

Schuckit, Marc A; Smith, Tom L; Heron, Jon; Hickman, Matthew; Macleod, John; Lewis, Glyn; Davis, John M; Hibbeln, Joseph R; Brown, Sandra; Zuccolo, Luisa; Miller, Laura L; Davey-Smith, George

2011-10-01

The low level of response (LR) to alcohol is one of several genetically influenced characteristics that increase the risk for heavy drinking and alcohol problems. Efforts to understand how LR operates through additional life influences have been carried out primarily in modest-sized U.S.-based samples with limited statistical power, raising questions about generalizability and about the importance of components with smaller effects. This study evaluates a full LR-based model of risk in a large sample of adolescents from the United Kingdom. Cross-sectional structural equation models were used for the approximate first half of the age 17 subjects assessed by the Avon Longitudinal Study of Parents and Children, generating data on 1,905 adolescents (mean age 17.8 years, 44.2% boys). LR was measured with the Self-Rating of the Effects of Alcohol Questionnaire, outcomes were based on drinking quantities and problems, and standardized questionnaires were used to evaluate peer substance use, alcohol expectancies, and using alcohol to cope with stress. In this young and large U.K. sample, a low LR related to more adverse alcohol outcomes both directly and through partial mediation by all 3 additional key variables (peer substance use, expectancies, and coping). The models were similar in boys and girls. These results confirm key elements of the hypothesized LR-based model in a large U.K. sample, supporting some generalizability beyond U.S. groups. They also indicate that with enough statistical power, multiple elements contribute to how LR relates to alcohol outcomes and reinforce the applicability of the model to both genders. Copyright © 2011 by the Research Society on Alcoholism.

Does classification of persons with fibromyalgia into Multidimensional Pain Inventory subgroups detect differences in outcome after a standard chronic pain management program?

PubMed Central

Verra, Martin L; Angst, Felix; Brioschi, Roberto; Lehmann, Susanne; Keefe, Francis J; Staal, J Bart; de Bie, Rob A; Aeschlimann, André

2009-01-01

INTRODUCTION: The present study aimed to replicate and validate the empirically derived subgroup classification based on the Multidimensional Pain Inventory (MPI) in a sample of highly disabled fibromyalgia (FM) patients. Second, it examined how the identified subgroups differed in their response to an intensive, interdisciplinary inpatient pain management program. METHODS: Participants were 118 persons with FM who experienced persistent pain and were disabled. Subgroup classification was conducted by cluster analysis using MPI subscale scores at entry to the program. At program entry and discharge, participants completed the MPI, Medical Outcomes Study Short Form-36, Hospital Anxiety and Depression Scale and Coping Strategies Questionnaire. RESULTS: Cluster analysis identified three subgroups in the highly disabled sample that were similar to those described by other studies using less disabled samples of FM. The dysfunctional subgroup (DYS; 36% of the sample) showed the highest level of depression, the interpersonally distressed subgroup (ID; 24%) showed a modest level of depression and the adaptive copers subgroup (AC; 38%) showed the lowest depression scores in the MPI (negative mood), Medical Outcomes Study Short Form-36 (mental health), Hospital Anxiety and Depression Scale (depression) and Coping Strategies Questionnaire (catastrophizing). Significant differences in treatment outcome were observed among the three subgroups in terms of reduction of pain severity (as assessed using the MPI). The effect sizes were 1.42 for DYS, 1.32 for AC and 0.62 for ID (P=0.004 for pairwise comparison of ID-AC and P=0.018 for ID-DYS). DISCUSSION: These findings underscore the importance of assessing individuals’ differences in how they adjust to FM. PMID:20011715

The relationship between processing style, trauma memory processes, and the development of posttraumatic stress symptoms in children and adolescents.

PubMed

McKinnon, Anna; Brewer, Neil; Cameron, Kate; Nixon, Reginald D V

2017-12-01

Data-driven processing, peri-event fear, and trauma memory characteristics are hypothesised to play a core role in the development of Posttraumatic Stress Disorder. We assessed the relationships between these characteristics and Posttraumatic Stress (PTS) symptoms in a sample of youth. Study 1 (N = 36, 7-16 years), involved a sample of children who had undergone a stressful orthopaedic procedure. One week later they answered a series of probed recall questions about the trauma (assessed for accuracy by comparison to a video) and reported on their PTS symptoms. They also rated confidence in their probed recall answers to assess meta-cognitive monitoring of their memory for the trauma. In Study 2, a sample of injured children (N = 57, 7-16 years) were assessed within 1-month of a visit to an Emergency Department, and then at 3-month follow-up. They answered probed recall questions, made confidence ratings, and completed measures of data-driven processing, peri-event fear, PTS and associated psychopathology. Memories were verified using witness accounts. Studies 1 and 2 did not find an association between PTS symptoms and trauma memory accuracy or confidence. In Studies 1 and 2 data-driven processing predicted PTS symptoms. The studies had modest samples sizes and there were ceiling effects for some accuracy and confidence items. Data-driven processing at the time of a trauma was associated with PTS symptoms after accounting for fear at the time of the trauma. Accuracy of recall for trauma memories was not significantly related to PTS symptoms. No decisive conclusion could be drawn regarding the relation between confidence in trauma memories and PTS symptoms. Copyright © 2017 Elsevier Ltd. All rights reserved.

A preliminary study of the population-adjusted effectiveness of substance abuse prevention programming: towards making IOM program types comparable.

PubMed

Shamblen, Stephen R; Derzon, James H

2009-03-01

The Institute of Medicine distinguishes between programs based on who is targeted: the entire population (universal), those at risk (selective), or persons exhibiting the early stages of use or related problem behavior (indicated). Evaluations suggest that although universal programs can be effective in reducing and preventing substance use, selective and indicated programs are both more effective and have greater cost-benefit ratios. This paper tests these assumptions by comparing the impact of these program types in reducing and preventing substance use at the individual level (i.e., those exposed to intervention services) and in the population (i.e., those exposed and not exposed to intervention services). A meta-analysis was performed on 43 studies of 25 programs to examine program comparability across IOM categories. When examining unadjusted effect sizes at the individual level, universal programs were modestly more successful in reducing tobacco use, but selective and indicated programs were modestly more successful in reducing alcohol and marijuana use. When adjusted to the population level, the average effect sizes for selective and indicated programs were reduced by approximately half. At the population level, universal programs were more successful in reducing tobacco and marijuana use and selective and indicated programs were more successful in reducing alcohol use. Editors' Strategic Implications: the authors' focus on the public health value of a prevention strategy is compelling and provides a model for analyses of other strategies and content areas.

MODEST - JPL GEODETIC AND ASTROMETRIC VLBI MODELING AND PARAMETER ESTIMATION PROGRAM

NASA Technical Reports Server (NTRS)

Sovers, O. J.

1994-01-01

Observations of extragalactic radio sources in the gigahertz region of the radio frequency spectrum by two or more antennas, separated by a baseline as long as the diameter of the Earth, can be reduced, by radio interferometry techniques, to yield time delays and their rates of change. The Very Long Baseline Interferometric (VLBI) observables can be processed by the MODEST software to yield geodetic and astrometric parameters of interest in areas such as geophysical satellite and spacecraft tracking applications and geodynamics. As the accuracy of radio interferometry has improved, increasingly complete models of the delay and delay rate observables have been developed. MODEST is a delay model (MOD) and parameter estimation (EST) program that takes into account delay effects such as geometry, clock, troposphere, and the ionosphere. MODEST includes all known effects at the centimeter level in modeling. As the field evolves and new effects are discovered, these can be included in the model. In general, the model includes contributions to the observables from Earth orientation, antenna motion, clock behavior, atmospheric effects, and radio source structure. Within each of these categories, a number of unknown parameters may be estimated from the observations. Since all parts of the time delay model contain nearly linear parameter terms, a square-root-information filter (SRIF) linear least-squares algorithm is employed in parameter estimation. Flexibility (via dynamic memory allocation) in the MODEST code ensures that the same executable can process a wide array of problems. These range from a few hundred observations on a single baseline, yielding estimates of tens of parameters, to global solutions estimating tens of thousands of parameters from hundreds of thousands of observations at antennas widely distributed over the Earth's surface. Depending on memory and disk storage availability, large problems may be subdivided into more tractable pieces that are processed sequentially. MODEST is written in FORTRAN 77, C-language, and VAX ASSEMBLER for DEC VAX series computers running VMS. It requires 6Mb of RAM for execution. The standard distribution medium for this package is a 1600 BPI 9-track magnetic tape in DEC VAX BACKUP format. It is also available on a TK50 tape cartridge in DEC VAX BACKUP format. Instructions for use and sample input and output data are available on the distribution media. This program was released in 1993 and is a copyrighted work with all copyright vested in NASA.

The relationship between job satisfaction and health: a meta-analysis

PubMed Central

Faragher, E; Cass, M; Cooper, C

2005-01-01

Background: A vast number of published studies have suggested a link between job satisfaction levels and health. The sizes of the relationships reported vary widely. Narrative overviews of this relationship have been published, but no systematic meta-analysis review has been conducted. Methods: A systematic review and meta-analysis of 485 studies with a combined sample size of 267 995 individuals was conducted, evaluating the research evidence linking self-report measures of job satisfaction to measures of physical and mental wellbeing. Results: The overall correlation combined across all health measures was r = 0.312 (0.370 after Schmidt-Hunter adjustment). Job satisfaction was most strongly associated with mental/psychological problems; strongest relationships were found for burnout (corrected r = 0.478), self-esteem(r = 0.429), depression (r = 0.428), and anxiety(r = 0.420). The correlation with subjective physical illness was more modest (r = 0.287). Conclusions: Correlations in excess of 0.3 are rare in this context. The relationships found suggest that job satisfaction level is an important factor influencing the health of workers. Organisations should include the development of stress management policies to identify and eradicate work practices that cause most job dissatisfaction as part of any exercise aimed at improving employee health. Occupational health clinicians should consider counselling employees diagnosed as having psychological problems to critically evaluate their work—and help them to explore ways of gaining greater satisfaction from this important aspect of their life. PMID:15657192

The French national survey on food consumption of children under 3 years of age - Nutri-Bébé 2013: design, methodology, population sampling and feeding practices.

PubMed

Chouraqui, Jean-Pierre; Tavoularis, Gabriel; Emery, Yves; Francou, Aurée; Hébel, Pascale; Bocquet, Magali; Hankard, Régis; Turck, Dominique

2018-02-01

To update the data on food consumption and practices in children under 3 years of age in metropolitan France. The Nutri-Bébé 2013 cross-sectional study selected a random sample, according to the quota sampling method. After giving their informed consent, parents had to record the food consumption during three non-consecutive days framed by two face-to-face interviews, using for quantitative information different portion size measurement aids. One thousand one hundred and eighty-four children were enrolled. Mothers' mean age was 30·8 (sd 5·4) years; 38 % were primiparous; 89 % lived with a partner; 60 % had an occupation. Of the infants younger than 4 months, 31 % were breast-fed. One thousand and thirty-five children consumed infant formula followed by growing-up milk in 63 % of them; solid foods were introduced at a mean age of 5·4 (sd 2·13) months. From 8 months onwards, 25 % of children consumed the same foods as their parents on a more or less regular basis; 29 % ate in front of a screen, with a daily average screen time of 43·0 (sd 40·4) min. This robust survey highlights the low prevalence and duration of breast-feeding in France and shows a modest improvement since the previous survey of 2005 in the observance of recommendations concerning other feeding practices. The frequent consumption of adult foods and the screen time are of concern.

SOLID-STATE SYNTHESIS AND SOME PROPERTIES OF MAGNESIUM-DOPED COPPER ALUMINUM OXIDES

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

Liu, Chang; Ren, Fei; Wang, Hsin

2010-01-01

Copper aluminum oxide (CuAlO2) with delafossite structure is a promising candidate for high temperature thermoelectric applications because of its modest band gap, high stability and low cost. We investigate magnesium doping on the aluminum site as a means of producing higher electrical conductivity and optimized Seebeck coefficient. Powder samples were synthesized using solid-state reaction and bulk samples were prepared using both cold-pressing and hot-pressing techniques. Composition analysis, microstructural examination and transport property measurements were performed, and the results suggest that while hot-pressing can achieve high density samples, secondary phases tend to form and lower the performance of the materials.

Examination of Sex Differences in a Large Sample of Young Children with Autism Spectrum Disorder and Typical Development

ERIC Educational Resources Information Center

Reinhardt, Vanessa P.; Wetherby, Amy M.; Schatschneider, Christopher; Lord, Catherine

2015-01-01

Despite consistent and substantive research documenting a large male to female ratio in Autism Spectrum Disorder (ASD), only a modest body of research exists examining sex differences in characteristics. This study examined sex differences in developmental functioning and early social communication in children with ASD as compared to children with…

24 CFR 891.670 - Cost containment and modest design standards.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Cost containment and modest design... Handicapped Families and Individuals-Section 162 Assistance § 891.670 Cost containment and modest design standards. (a) Restrictions on amenities. Projects must be modest in design. Except as provided in paragraph...

24 CFR 891.670 - Cost containment and modest design standards.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Cost containment and modest design... Handicapped Families and Individuals-Section 162 Assistance § 891.670 Cost containment and modest design standards. (a) Restrictions on amenities. Projects must be modest in design. Except as provided in paragraph...

24 CFR 891.670 - Cost containment and modest design standards.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Cost containment and modest design... Handicapped Families and Individuals-Section 162 Assistance § 891.670 Cost containment and modest design standards. (a) Restrictions on amenities. Projects must be modest in design. Except as provided in paragraph...

24 CFR 891.670 - Cost containment and modest design standards.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Cost containment and modest design... Handicapped Families and Individuals-Section 162 Assistance § 891.670 Cost containment and modest design standards. (a) Restrictions on amenities. Projects must be modest in design. Except as provided in paragraph...

24 CFR 891.670 - Cost containment and modest design standards.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Cost containment and modest design... Handicapped Families and Individuals-Section 162 Assistance § 891.670 Cost containment and modest design standards. (a) Restrictions on amenities. Projects must be modest in design. Except as provided in paragraph...

Residential scene classification for gridded population sampling in developing countries using deep convolutional neural networks on satellite imagery.

PubMed

Chew, Robert F; Amer, Safaa; Jones, Kasey; Unangst, Jennifer; Cajka, James; Allpress, Justine; Bruhn, Mark

2018-05-09

Conducting surveys in low- and middle-income countries is often challenging because many areas lack a complete sampling frame, have outdated census information, or have limited data available for designing and selecting a representative sample. Geosampling is a probability-based, gridded population sampling method that addresses some of these issues by using geographic information system (GIS) tools to create logistically manageable area units for sampling. GIS grid cells are overlaid to partition a country's existing administrative boundaries into area units that vary in size from 50 m × 50 m to 150 m × 150 m. To avoid sending interviewers to unoccupied areas, researchers manually classify grid cells as "residential" or "nonresidential" through visual inspection of aerial images. "Nonresidential" units are then excluded from sampling and data collection. This process of manually classifying sampling units has drawbacks since it is labor intensive, prone to human error, and creates the need for simplifying assumptions during calculation of design-based sampling weights. In this paper, we discuss the development of a deep learning classification model to predict whether aerial images are residential or nonresidential, thus reducing manual labor and eliminating the need for simplifying assumptions. On our test sets, the model performs comparable to a human-level baseline in both Nigeria (94.5% accuracy) and Guatemala (96.4% accuracy), and outperforms baseline machine learning models trained on crowdsourced or remote-sensed geospatial features. Additionally, our findings suggest that this approach can work well in new areas with relatively modest amounts of training data. Gridded population sampling methods like geosampling are becoming increasingly popular in countries with outdated or inaccurate census data because of their timeliness, flexibility, and cost. Using deep learning models directly on satellite images, we provide a novel method for sample frame construction that identifies residential gridded aerial units. In cases where manual classification of satellite images is used to (1) correct for errors in gridded population data sets or (2) classify grids where population estimates are unavailable, this methodology can help reduce annotation burden with comparable quality to human analysts.

Sexual attitudes, preferences and infections in Ancient Greece: has antiquity anything useful for us today?

PubMed Central

Morton, R S

1991-01-01

Modern society bears a heavy burden of medico-social pathology particularly amongst its young. The size, nature and costs of the sexually transmitted disease element is now considerable and dwarfs such successes as have been achieved. In the belief that the structure of a society and the way that structure functions determines the size of its STD problem, a review of Ancient Greek society has been undertaken. Greek society, not least concerning all aspects of sex, was well ordered, frank and tolerant. Some of the areas of Greek society's structure and functioning which differ most markedly from ours, and seem to have determined a modest STD problem, are highlighted and discussed. Greek ideas that might be adapted to match today's needs are presented for consideration. PMID:1916781

Perceived sources of change in trainees' self-efficacy beliefs.

PubMed

Lent, Robert W; Cinamon, Rachel Gali; Bryan, Nicole A; Jezzi, Matthew M; Martin, Helena M; Lim, Robert

2009-09-01

Thought-listing procedures were used to examine the perceived incidence, size, direction, and bases of change in the session-level self-efficacy of therapists in training. Ninety-eight Master's-level trainees completed a cognitive assessment task immediately after each session with a client in their first practicum. Participants typically reported modest-sized, positive changes in their therapeutic self-efficacy at each session. Seven perceived sources of change in self-efficacy were identified. Some of these sources (e.g., trainees' performance evaluations, affective reactions) were consistent with general self-efficacy theory; others reflected the interpersonal performance context of therapy (e.g., perceptions of the therapeutic relationship and client behavior). Implications of the findings for training and future research on therapist development are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Preparation and Performance of Porous Polymer Electrolytes Doped with Nano-Al₂O₃.

PubMed

Jiang, Qingbai; Liang, Bo; Tang, Siqi; Chen, Xu

2018-03-01

Porous polymer electrolytes (PPEs) doped with nano-Al2O3 were prepared by a joint application of ultrasonic treatment and control evaporation in vacuum oven. The morphology, pore size distribution, thermal, electrochemical and mechanical properties of the PPEs were investigated. The porosity distribution of PPEs was uniform and their pore size was relatively modest. The total resistance (Rt) of PPEs with 10% Al2O3 is only 9 Ω at 80 °C. The maximum tensile strength of the PPEs membranes reached to 24.43 MPa. The results show that nano-Al2O3 can improve the comprehensive performance of PPEs without compromising their conductivity and diplayed the good application prospects of Al2O3-modified PPEs for lithium-ion batteries.

BigView Image Viewing on Tiled Displays

NASA Technical Reports Server (NTRS)

Sandstrom, Timothy

2007-01-01

BigView allows for interactive panning and zooming of images of arbitrary size on desktop PCs running Linux. Additionally, it can work in a multi-screen environment where multiple PCs cooperate to view a single, large image. Using this software, one can explore on relatively modest machines images such as the Mars Orbiter Camera mosaic [92,160 33,280 pixels]. The images must be first converted into paged format, where the image is stored in 256 256 pages to allow rapid movement of pixels into texture memory. The format contains an image pyramid : a set of scaled versions of the original image. Each scaled image is 1/2 the size of the previous, starting with the original down to the smallest, which fits into a single 256 x 256 page.

Profound metabolic acidosis and oxoprolinuria in an adult.

PubMed

Hodgman, Michael J; Horn, James F; Stork, Christine M; Marraffa, Jeanna M; Holland, Michael G; Cantor, Richard; Carmel, Patti M

2007-09-01

Profound metabolic acidosis in critically ill adults sometimes remains unexplained despite extensive evaluation. A 58-year-old female presented in a confused state to the emergency department; she had been confused for several days. Laboratory evaluation revealed a high anion gap metabolic acidosis and modestly elevated acetaminophen level. Lactic acid was only modestly elevated. There was no evidence of ketoacids, salicylate, methanol, or ethylene glycol. A urine sample submitted on day 1 of hospitalization revealed a markedly elevated level of 5-oxoproline. Originally described in children with an inherited defect of glutathione synthetase, 5-oxoproline is an unusual cause of metabolic acidosis. More recently this disturbance has been recognized in critically ill adults without a recognized inherited metabolic disorder. In most of these cases there has been the concomitant use of acetaminophen. Any causal relationship between acetaminophen and this disturbance is speculative. In critically ill adults with unexplained metabolic acidosis, 5-Oxoproline should be considered in the differential.

Waterspout, Gust Fronts and Associated Cloud Systems

NASA Technical Reports Server (NTRS)

Simpson, J.

1983-01-01

Nine waterspouts observed on five experimental days during the GATE period of observations are discussed. Primary data used are from 2 aircraft flying in different patterns, one above the other between 30 and 300 m. There is strong evidence associating whirl initiation with cumulus outflow. Computations prepared from estimates of convergence with the region suggest the possibility of vortex generation within 4 minutes. This analysis supports (1) the importance cumulus outflows may have in waterspout initiation and (2) the possibility that sea surface temperature gradients may be important in enabling waterspout development from modest size cumuli.

Montreal Cognitive Assessment for screening mild cognitive impairment: variations in test performance and scores by education in Singapore.

PubMed

Ng, Tze Pin; Feng, Lei; Lim, Wee Shiong; Chong, Mei Sian; Lee, Tih Shih; Yap, Keng Bee; Tsoi, Tung; Liew, Tau Ming; Gao, Qi; Collinson, Simon; Kandiah, Nagaendran; Yap, Philip

2015-01-01

The Montreal Cognitive Assessment (MoCA) was developed as a screening instrument for mild cognitive impairment (MCI). We evaluated the MoCA's test performance by educational groups among older Singaporean Chinese adults. The MoCA and Mini-Mental State Examination (MMSE) were evaluated in two independent studies (clinic-based sample and community-based sample) of MCI and normal cognition (NC) controls, using receiver operating characteristic curve analyses: area under the curve (AUC), sensitivity (Sn), and specificity (Sp). The MoCA modestly discriminated MCI from NC in both study samples (AUC = 0.63 and 0.65): Sn = 0.64 and Sp = 0.36 at a cut-off of 28/29 in the clinic-based sample, and Sn = 0.65 and Sp = 0.55 at a cut-off of 22/23 in the community-based sample. The MoCA's test performance was least satisfactory in the highest (>6 years) education group: AUC = 0.50 (p = 0.98), Sn = 0.54, and Sp = 0.51 at a cut-off of 27/28. Overall, the MoCA's test performance was not better than that of the MMSE. In multivariate analyses controlling for age and gender, MCI diagnosis was associated with a <1-point decrement in MoCA score (η(2) = 0.010), but lower (1-6 years) and no education was associated with a 3- to 5-point decrement (η(2) = 0.115 and η(2) = 0.162, respectively). The MoCA's ability to discriminate MCI from NC was modest in this Chinese population, because it was far more sensitive to the effect of education than MCI diagnosis. © 2015 S. Karger AG, Basel.

Mass-specific scattering coefficient for natural minerogenic particle populations: particle size distribution effect and closure analyses.

PubMed

Peng, Feng; Effler, Steve W

2012-05-01

The relationship between the particulate scattering coefficient (b(p)) and the concentration of suspended particulate matter (SPM), as represented by the mass-specific scattering coefficient of particulates (b(p)*=b(p)/SPM), depends on particle size distribution (PSD). This dependence is quantified for minerogenic particle populations in this paper through calculations of b(p)* for common minerals as idealized populations (monodispersed spheres); contemporaneous measurements of b(p), SPM, and light-scattering attributes of mineral particles with scanning electron microscopy interfaced with automated image and x-ray analyses (SAX), for a connected stream-reservoir system where minerogenic particles dominate b(p); and estimates of b(p) and its size dependency (through SAX results-driven Mie theory calculations), particle volume concentration, and b(p)*. Modest changes in minerogenic PSDs are shown to result in substantial variations in b(p)*. Good closure of the SAX-based estimates of b(p) and particle volume concentration with bulk measurements is demonstrated. Converging relationships between b(p)* and particle size, developed from three approaches, were well described by power law expressions.

Major malformation risk, pregnancy outcomes, and neurodevelopmental outcomes associated with metformin use during pregnancy.

PubMed

Andrade, Chittaranjan

2016-04-01

There are several reasons why metformin treatment may be considered for women in neuropsychiatric practice. These include prevention or attenuation of antipsychotic-associated weight gain, prevention or treatment of gestational diabetes mellitus (GDM), treatment of type 2 diabetes mellitus, and improvement of conception chances and pregnancy outcomes in the presence of polycystic ovarian disease (PCOD). This article examines the benefits and risks associated with metformin use during pregnancy. The available data suggest that metformin exposure during the first trimester is not associated with major congenital malformations; that metformin reduces the risk of early pregnancy loss, preeclampsia, preterm delivery, and GDM in women with PCOD; that metformin is associated with at least comparable benefits relative to insulin treatment in women with mild GDM; and that neurodevelopmental outcomes at age 1.5-2.5 years are comparable after gestational exposure to metformin and insulin. Whereas study designs were not always ideal and sample sizes were mostly small to modest, the study findings are more encouraging than discouraging and can guide shared decision-making in women who are receiving or may need metformin during pregnancy. © Copyright 2016 Physicians Postgraduate Press, Inc.

Exo-C: A Space Mission for Direct Imaging and Spectroscopy of Extrasolar Planetary Systems

NASA Technical Reports Server (NTRS)

Stapelfeldt, Karl; Belikov, Ruslan; Marley, Mark; Bryden, Geoff; Serabyn, Eugene; Trauger, John; Cahoy, Kerri; Chakrabarti, Supriya; McElwain, Michael; Meadows, Victoria;

A new approach for bioassays based on frequency- and time-domain measurements of magnetic nanoparticles.

PubMed

Oisjöen, Fredrik; Schneiderman, Justin F; Astalan, Andrea Prieto; Kalabukhov, Alexey; Johansson, Christer; Winkler, Dag

2010-01-15

We demonstrate a one-step wash-free bioassay measurement system capable of tracking biochemical binding events. Our approach combines the high resolution of frequency- and high speed of time-domain measurements in a single device in combination with a fast one-step bioassay. The one-step nature of our magnetic nanoparticle (MNP) based assay reduces the time between sample extraction and quantitative results while mitigating the risks of contamination related to washing steps. Our method also enables tracking of binding events, providing the possibility of, for example, investigation of how chemical/biological environments affect the rate of a binding process or study of the action of certain drugs. We detect specific biological binding events occurring on the surfaces of fluid-suspended MNPs that modify their magnetic relaxation behavior. Herein, we extrapolate a modest sensitivity to analyte of 100 ng/ml with the present setup using our rapid one-step bioassay. More importantly, we determine the size-distributions of the MNP systems with theoretical fits to our data obtained from the two complementary measurement modalities and demonstrate quantitative agreement between them. Copyright 2009 Elsevier B.V. All rights reserved.

Can Brief Alcohol Interventions for Youth Also Address Concurrent Illicit Drug Use? Results from a Meta-analysis

PubMed Central

Tanner-Smith, Emily E.; Steinka-Fry, Katarzyna T.; Hennessy, Emily A.; Lipsey, Mark W.; Winters, Ken C.

2015-01-01

Brief interventions aimed at reducing alcohol use among youth may interrupt a possible developmental progression to more serious substance use if they can also affect the use of other illicit drugs. This meta-analysis examined the findings of recent research on the effects of brief alcohol interventions for adolescents and young adults on both alcohol and illicit drug use. Eligible studies were those using randomized or controlled quasi-experimental designs to examine the effects of brief alcohol interventions on illicit drug use outcomes among youth. A comprehensive literature search identified 30 eligible study samples that, on average, included participants age 17, with 57% male participants and 56% White youth. Three-level random-effects meta-analyses were used to estimate mean effect sizes and explore variability in effects. Overall, brief interventions targeting both alcohol and other drugs were effective in reducing both of these substances. However, the brief interventions that targeted only alcohol had no significant secondary effects on untargeted illicit drug use. The evidence from current research, therefore, shows modest beneficial effects on outcomes that are targeted by brief interventions for youth, but does not show that those effects generalize to untargeted illicit drug use outcomes. PMID:25600491

The Correlation between Mixing Length and Metallicity on the Giant Branch: Implications for Ages in the Gaia Era

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

Tayar, Jamie; Somers, Garrett; Pinsonneault, Marc H.

2017-05-01

In the updated APOGEE- Kepler catalog, we have asteroseismic and spectroscopic data for over 3000 first ascent red giants. Given the size and accuracy of this sample, these data offer an unprecedented test of the accuracy of stellar models on the post-main-sequence. When we compare these data to theoretical predictions, we find a metallicity dependent temperature offset with a slope of around 100 K per dex in metallicity. We find that this effect is present in all model grids tested, and that theoretical uncertainties in the models, correlated spectroscopic errors, and shifts in the asteroseismic mass scale are insufficient tomore » explain this effect. Stellar models can be brought into agreement with the data if a metallicity-dependent convective mixing length is used, with Δ α {sub ML,YREC} ∼ 0.2 per dex in metallicity, a trend inconsistent with the predictions of three-dimensional stellar convection simulations. If this effect is not taken into account, isochrone ages for red giants from the Gaia data will be off by as much as a factor of two even at modest deviations from solar metallicity ([Fe/H] = −0.5).« less

HIV prevention in Africa: programs and populations served by non-governmental organizations.

PubMed

Benotsch, Eric G; Stevenson, L Yvonne; Sitzler, Cheryl A; Kelly, Jeffrey A; Makhaye, Gethwana; Mathey, Eric Dodji; Somlai, Anton M; Brown, Kevin D; Amirkhanian, Yuri; Fernandez, M Isabel; Opgenorth, Karen M

2004-08-01

The AIDS epidemic in Africa remains an urgent health crisis. Non-governmental organizations (NGOs) in Africa play a critical role in the delivery of HIV prevention services and assistance to persons living with AIDS. African NGOs are conducting numerous HIV prevention programs with several at-risk populations, yet their efforts have only rarely been systematically documented. To address this gap in the literature, the authors surveyed one NGO in each of 29 African countries regarding their HIV prevention activities and populations served. This report provides details concerning HIV prevention activities across the continent and describes in detail innovative programs from Togo and South Africa. NGOs in the present sample operate with modest budgets and small staff sizes, yet conduct programs that reach large segments of their communities. NGOs were most likely to report community-level interventions such as peer-education or community outreach. Faced with an epidemic where the main transmission occurs via heterosexual activity, African NGOs were most likely to direct their attention to the general public and to youth. NGOs in Africa are struggling to implement sustainable, cost-effective programs with few resources. Strengthening the infrastructure and capacity of these key agencies is crucial to fighting the AIDS epidemic in Africa.

Effect of BDNF val(66)met polymorphism on declarative memory and its neural substrate: a meta-analysis.

PubMed

Kambeitz, Joseph P; Bhattacharyya, Sagnik; Kambeitz-Ilankovic, Lana M; Valli, Isabel; Collier, David A; McGuire, Philip

2012-10-01

Brain derived neurotrophic factor (BDNF) is a critical component of the molecular mechanism of memory formation. Variation in the BDNF gene, particularly the rs6265 (val(66)met) single nucleotide polymorphism (SNP), has been linked to variability in human memory performance and to both the structure and physiological response of the hippocampus, which plays a central role in memory processing. However, these effects have not been consistently reported, which may reflect the modest size of the samples studied to date. Employing a meta-analytic approach, we examined the effect of the BDNF val(66)met polymorphism on human memory (5922 subjects) and hippocampal structure (2985 subjects) and physiology (362 subjects). Our results suggest that variations in the rs6265 SNP of the BDNF gene have a significant effect on memory performance, and on both the structure and physiology of the hippocampus, with carriers of the met allele being adversely affected. These results underscore the role of BDNF in moderating variability between individuals in human memory performance and in mediating some of the neurocognitive impairments underlying neuropsychiatric disorders. Copyright © 2012 Elsevier Ltd. All rights reserved.

A critical appraisal of nutritional intervention studies in malnourished, community dwelling older persons.

PubMed

de van der Schueren, M A E; Wijnhoven, H A H; Kruizenga, H M; Visser, M

2016-10-01

With the rapidly increasing number of malnourished older persons in the community, this review aims to summarize the effects of nutritional intervention studies for this target group. Based on 2 previous reviews (2009, 2011) an update of the literature was performed. Selected were higher quality studies which included malnourished community dwelling older adults who received dietetic counselling and/or oral nutritional supplements. Ten studies were included. Six studies showed (trends towards) weight gain. Meta-analysis showed a modest effect of the intervention on weight gain, standardized mean difference 0.210 kg (95% CI 0.03-0.40). Effects on other relevant functional and clinical outcomes were inconsistent. Studies were hampered by low sample sizes, low adherence to the interventions, and participants not meeting nutritional requirements. Currently, nutritional intervention studies for malnourished community dwelling older adults show limited effects, which may be caused by methodological shortcomings and participants not meeting treatment goals. High quality studies are eagerly awaited to be able to identify (sub)groups of older persons who are most likely to benefit from nutritional support. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Linking Physical and Mental Health Summary Scores from the Veterans RAND 12-Item Health Survey (VR-12) to the PROMIS(®) Global Health Scale.

PubMed

Schalet, Benjamin D; Rothrock, Nan E; Hays, Ron D; Kazis, Lewis E; Cook, Karon F; Rutsohn, Joshua P; Cella, David

2015-10-01

Global health measures represent an attractive option for researchers and clinicians seeking a brief snapshot of a patient's overall perspective on his or her health. Because scores on different global health measures are not comparable, comparative effectiveness research (CER) is challenging. To establish a common reporting metric so that the physical and mental health scores on the Veterans RAND 12-Item Health Survey (VR-12 (©) ) can be converted into scores on the corresponding Patient Reported Outcomes Measurement Information System (PROMIS(®)) Global Health scores. Following a single-sample linking design, participants from an Internet panel completed items from the PROMIS Global Health and VR-12 Health Survey. A common metric was created using analyses based on item response theory (IRT), producing score cross-walk tables for the mental and physical health components of each measure. The linking relationships were evaluated by calculating the standard deviation of differences between the observed and linked PROMIS scores and estimating confidence intervals by sample size. Participants (N = 2025) were 49 % male and 73 % white; mean age was 46 years. Mental and physical health subscales of the PROMIS Global Health and the VR-12. The mean VR-12 physical component and mental component scores were 45.2 and 46.6, respectively; the mean PROMIS physical and mental health scores were 48.3 and 48.5, respectively. We found evidence that the combined set of VR-12 and PROMIS items were relatively unidimensional and that we could proceed with linking. Linking worked better between the physical health than mental health scores using VR-12 item responses (vs. linking based on algorithmic scores). For each of the cross-walks, users can minimize the impact of linking error with modest increases in sample sizes. VR-12 scores can be expressed on the PROMIS Global Health metric to facilitate the evaluation of treatment, including CER. Extending these results to other common measures of global health is encouraged.

The Projected Responses of Residency-Sponsoring Institutions to a Reduction in Medicare Support for Graduate Medical Education: A National Survey.

PubMed

Riaz, Mahrukh; Palermo, Tia; Yen, Michael; Edelman, Norman H

2015-10-01

To assess the projected responses of residency-sponsoring institutions to the proposed reduction in Medicare's indirect medical education (IME) payments. In 2012, the authors surveyed directors of graduate medical education (GME) programs, examining (1) overall responses to a reduction in IME reimbursement and (2) the value of individual residencies to the institution from the economic/operational and educational/public service points of view, to determine which programs may be at risk for downsizing. Responses from 192 of 555 institutions (35% response rate) varied by the size of the institution's GME program. Of large programs (six or more residencies), 33 (33%) would downsize at a 10% reduction in IME reimbursement, focusing cuts on specific programs. Small programs (five or fewer residencies) were more likely to retain their existing residencies with modest IME payment reductions and to make across-the-board cuts. The economic/operational value of specialties varied widely, with hospital-intensive residencies valued highest. Family medicine was valued highly from an economic/operational point of view only by small programs. Educational/public service value scores varied less and were higher for all specialties. Preventive medicine was not highly valued in either category. Even a modest decrease in IME reimbursement could trigger institutions to downsize their GME programs. Programs at the greatest risk for cuts may be those with modest economic/operational value but high societal value, like family medicine. The retention or expansion of training in family medicine may be most easily accomplished then at smaller institutions.

Photometric Studies of GEO Debris

NASA Technical Reports Server (NTRS)

Seitzer, Patrick; Cowardin, Heather M.; Barker, Edwin; Abercromby, Kira J.; Foreman, Gary; Horstman, Matt

2009-01-01

The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the SMARTS (Small and Medium Aperture Research Telescope System) 0.9-m at CTIO for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R = 15 th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? In this paper we report on the photometric results. For a sample of 50 objects, more than 90 calibrated sequences of R-B-V-I-R magnitudes have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus the B-R color is a true measure of the surface of the debris piece facing the telescopes for that observation. Any change in color reflects a real change in the debris surface.

Photometric Studies of GEO Orbital Debris

NASA Technical Reports Server (NTRS)

Seitzer, Patrick; Rodriquez-Cowardin, Heather M.; Barker, Ed; Abercromby, Kira J.; Foreman, Gary; Horstman, Matt

2009-01-01

The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the Cerro Tololo Inter- American Observatory (CTIO) 0.9-m for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R=15th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? More than 90 calibrated sequences of R-B-V-I-R magnitudes for a sample of 50 objects have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus the B-R color is a true measure of the surface of the debris piece facing the telescopes for that observation. Any change in color reflects a real change in the debris surface. We will compare our observations with models and laboratory measurements of selected surfaces.

Evaluation of bias and logistics in a survey of adults at increased risk for oral health decrements.

PubMed

Gilbert, G H; Duncan, R P; Kulley, A M; Coward, R T; Heft, M W

1997-01-01

Designing research to include sufficient respondents in groups at highest risk for oral health decrements can present unique challenges. Our purpose was to evaluate bias and logistics in this survey of adults at increased risk for oral health decrements. We used a telephone survey methodology that employed both listed numbers and random digit dialing to identify dentate persons 45 years old or older and to oversample blacks, poor persons, and residents of nonmetropolitan counties. At a second stage, a subsample of the respondents to the initial telephone screening was selected for further study, which consisted of a baseline in-person interview and a clinical examination. We assessed bias due to: (1) limiting the sample to households with telephones, (2) using predominantly listed numbers instead of random digit dialing, and (3) nonresponse at two stages of data collection. While this approach apparently created some biases in the sample, they were small in magnitude. Specifically, limiting the sample to households with telephones biased the sample overall toward more females, larger households, and fewer functionally impaired persons. Using predominantly listed numbers led to a modest bias toward selection of persons more likely to be younger, healthier, female, have had a recent dental visit, and reside in smaller households. Blacks who were selected randomly at a second stage were more likely to participate in baseline data gathering than their white counterparts. Comparisons of the data obtained in this survey with those from recent national surveys suggest that this methodology for sampling high-risk groups did not substantively bias the sample with respect to two important dental parameters, prevalence of edentulousness and dental care use, nor were conclusions about multivariate associations with dental care recency substantively affected. This method of sampling persons at high risk for oral health decrements resulted in only modest bias with respect to the population of interest.

Small nucleoli are a cellular hallmark of longevity

PubMed Central

Tiku, Varnesh; Jain, Chirag; Raz, Yotam; Nakamura, Shuhei; Heestand, Bree; Liu, Wei; Späth, Martin; Suchiman, H. Eka. D.; Müller, Roman-Ulrich; Slagboom, P. Eline; Partridge, Linda; Antebi, Adam

2017-01-01

Animal lifespan is regulated by conserved metabolic signalling pathways and specific transcription factors, but whether these pathways affect common downstream mechanisms remains largely elusive. Here we show that NCL-1/TRIM2/Brat tumour suppressor extends lifespan and limits nucleolar size in the major C. elegans longevity pathways, as part of a convergent mechanism focused on the nucleolus. Long-lived animals representing distinct longevity pathways exhibit small nucleoli, and decreased expression of rRNA, ribosomal proteins, and the nucleolar protein fibrillarin, dependent on NCL-1. Knockdown of fibrillarin also reduces nucleolar size and extends lifespan. Among wildtype C. elegans, individual nucleolar size varies, but is highly predictive for longevity. Long-lived dietary restricted fruit flies and insulin-like-peptide mutants exhibit small nucleoli and fibrillarin expression, as do long-lived dietary restricted and IRS1 knockout mice. Furthermore, human muscle biopsies from individuals who underwent modest dietary restriction coupled with exercise also display small nucleoli. We suggest that small nucleoli are a cellular hallmark of longevity and metabolic health conserved across taxa. PMID:28853436

Small nucleoli are a cellular hallmark of longevity.

PubMed

Tiku, Varnesh; Jain, Chirag; Raz, Yotam; Nakamura, Shuhei; Heestand, Bree; Liu, Wei; Späth, Martin; Suchiman, H Eka D; Müller, Roman-Ulrich; Slagboom, P Eline; Partridge, Linda; Antebi, Adam

2016-08-30

Animal lifespan is regulated by conserved metabolic signalling pathways and specific transcription factors, but whether these pathways affect common downstream mechanisms remains largely elusive. Here we show that NCL-1/TRIM2/Brat tumour suppressor extends lifespan and limits nucleolar size in the major C. elegans longevity pathways, as part of a convergent mechanism focused on the nucleolus. Long-lived animals representing distinct longevity pathways exhibit small nucleoli, and decreased expression of rRNA, ribosomal proteins, and the nucleolar protein fibrillarin, dependent on NCL-1. Knockdown of fibrillarin also reduces nucleolar size and extends lifespan. Among wildtype C. elegans, individual nucleolar size varies, but is highly predictive for longevity. Long-lived dietary restricted fruit flies and insulin-like-peptide mutants exhibit small nucleoli and fibrillarin expression, as do long-lived dietary restricted and IRS1 knockout mice. Furthermore, human muscle biopsies from individuals who underwent modest dietary restriction coupled with exercise also display small nucleoli. We suggest that small nucleoli are a cellular hallmark of longevity and metabolic health conserved across taxa.

Assessment of time-dependent density functional theory with the restricted excitation space approximation for excited state calculations of large systems

NASA Astrophysics Data System (ADS)

Hanson-Heine, Magnus W. D.; George, Michael W.; Besley, Nicholas A.

2018-06-01

The restricted excitation subspace approximation is explored as a basis to reduce the memory storage required in linear response time-dependent density functional theory (TDDFT) calculations within the Tamm-Dancoff approximation. It is shown that excluding the core orbitals and up to 70% of the virtual orbitals in the construction of the excitation subspace does not result in significant changes in computed UV/vis spectra for large molecules. The reduced size of the excitation subspace greatly reduces the size of the subspace vectors that need to be stored when using the Davidson procedure to determine the eigenvalues of the TDDFT equations. Furthermore, additional screening of the two-electron integrals in combination with a reduction in the size of the numerical integration grid used in the TDDFT calculation leads to significant computational savings. The use of these approximations represents a simple approach to extend TDDFT to the study of large systems and make the calculations increasingly tractable using modest computing resources.

Characterization of bidisperse magnetorheological fluids utilizing maghemite (γ-Fe2O3) nanoparticles synthetized by flame spray pyrolysis

NASA Astrophysics Data System (ADS)

Jönkkäri, I.; Sorvali, M.; Huhtinen, H.; Sarlin, E.; Salminen, T.; Haapanen, J.; Mäkelä, J. M.; Vuorinen, J.

2017-09-01

In this study we have used liquid flame spray (LFS) process to synthetize γ-Fe2O3 nanoparticles of two different average sizes. Different sized nanoparticles were generated with two different liquid precursor feed rates in the spray process, higher feed rate resulting in larger nanoparticles with higher saturation magnetization. The nanoparticles were used in bidisperse magnetorheological fluids to substitute 5% of the micron sized carbonyl iron particles. To our knowledge this is the first time particles synthetized by the LFS method have been used in magnetorheological fluids. The bidisperse fluids showed significantly improved sedimentation stability compared to a monodisperse suspension with the same solid concentration. The tradeoff was an increased viscosity without magnetic field. The effect of the nanoparticles on the rheological properties under external magnetic field was modest. Finally, the dynamic oscillatory testing was used to evaluate the structural changes in the fluids under magnetic field. The addition of nanoparticles decreased the elastic portion of the deformation and increased the viscous portion.

The repeatability of mean defect with size III and size V standard automated perimetry.

PubMed

Wall, Michael; Doyle, Carrie K; Zamba, K D; Artes, Paul; Johnson, Chris A

2013-02-15

The mean defect (MD) of the visual field is a global statistical index used to monitor overall visual field change over time. Our goal was to investigate the relationship of MD and its variability for two clinically used strategies (Swedish Interactive Threshold Algorithm [SITA] standard size III and full threshold size V) in glaucoma patients and controls. We tested one eye, at random, for 46 glaucoma patients and 28 ocularly healthy subjects with Humphrey program 24-2 SITA standard for size III and full threshold for size V each five times over a 5-week period. The standard deviation of MD was regressed against the MD for the five repeated tests, and quantile regression was used to show the relationship of variability and MD. A Wilcoxon test was used to compare the standard deviations of the two testing methods following quantile regression. Both types of regression analysis showed increasing variability with increasing visual field damage. Quantile regression showed modestly smaller MD confidence limits. There was a 15% decrease in SD with size V in glaucoma patients (P = 0.10) and a 12% decrease in ocularly healthy subjects (P = 0.08). The repeatability of size V MD appears to be slightly better than size III SITA testing. When using MD to determine visual field progression, a change of 1.5 to 4 decibels (dB) is needed to be outside the normal 95% confidence limits, depending on the size of the stimulus and the amount of visual field damage.

Lack of replication of previous autism spectrum disorder GWAS hits in European populations.

PubMed

Torrico, Bàrbara; Chiocchetti, Andreas G; Bacchelli, Elena; Trabetti, Elisabetta; Hervás, Amaia; Franke, Barbara; Buitelaar, Jan K; Rommelse, Nanda; Yousaf, Afsheen; Duketis, Eftichia; Freitag, Christine M; Caballero-Andaluz, Rafaela; Martinez-Mir, Amalia; Scholl, Francisco G; Ribasés, Marta; Battaglia, Agatino; Malerba, Giovanni; Delorme, Richard; Benabou, Marion; Maestrini, Elena; Bourgeron, Thomas; Cormand, Bru; Toma, Claudio

2017-02-01

Common variants contribute significantly to the genetics of autism spectrum disorder (ASD), although the identification of individual risk polymorphisms remains still elusive due to their small effect sizes and limited sample sizes available for association studies. During the last decade several genome-wide association studies (GWAS) have enabled the detection of a few plausible risk variants. The three main studies are family-based and pointed at SEMA5A (rs10513025), MACROD2 (rs4141463) and MSNP1 (rs4307059). In our study we attempted to replicate these GWAS hits using a case-control association study in five European populations of ASD patients and gender-matched controls, all Caucasians. Results showed no association of individual variants with ASD in any of the population groups considered or in the combined European sample. We performed a meta-analysis study across five European populations for rs10513025 (1,904 ASD cases and 2,674 controls), seven European populations for rs4141463 (2,855 ASD cases and 36,177 controls) and five European populations for rs4307059 (2,347 ASD cases and 2,764 controls). The results showed an odds ratio (OR) of 1.05 (95% CI = 0.84-1.32) for rs10513025, 1.0002 (95% CI = 0.93-1.08) for rs4141463 and 1.01 (95% CI = 0.92-1.1) for rs4307059, with no significant P-values (rs10513025, P = 0.73; rs4141463, P = 0.95; rs4307059, P = 0.9). No association was found when we considered either only high functioning autism (HFA), genders separately or only multiplex families. Ongoing GWAS projects with larger ASD cohorts will contribute to clarify the role of common variation in the disorder and will likely identify risk variants of modest effect not detected previously. Autism Res 2017, 10: 202-211. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

DETAILED ABUNDANCES OF STARS WITH SMALL PLANETS DISCOVERED BY KEPLER. I. THE FIRST SAMPLE

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

Schuler, Simon C.; Vaz, Zachary A.; Santrich, Orlando J. Katime

2015-12-10

We present newly derived stellar parameters and the detailed abundances of 19 elements of seven stars with small planets discovered by NASA's Kepler Mission. Each star, save one, has at least one planet with a radius ≤1.6 R{sub ⊕}, suggesting a primarily rocky composition. The stellar parameters and abundances are derived from high signal-to-noise ratio, high-resolution echelle spectroscopy obtained with the 10 m Keck I telescope and High Resolution Echelle Spectrometer using standard spectroscopic techniques. The metallicities of the seven stars range from −0.32 to +0.13 dex, with an average metallicity that is subsolar, supporting previous suggestions that, unlike Jupiter-typemore » giant planets, small planets do not form preferentially around metal-rich stars. The abundances of elements other than iron are in line with a population of Galactic disk stars, and despite our modest sample size, we find hints that the compositions of stars with small planets are similar to stars without known planets and with Neptune-size planets, but not to those of stars with giant planets. This suggests that the formation of small planets does not require exceptional host-star compositions and that small planets may be ubiquitous in the Galaxy. We compare our derived abundances (which have typical uncertainties of ≲0.04 dex) to the condensation temperature of the elements; a correlation between the two has been suggested as a possible signature of rocky planet formation. None of the stars demonstrate the putative rocky planet signature, despite at least three of the stars having rocky planets estimated to contain enough refractory material to produce the signature, if real. More detailed abundance analyses of stars known to host small planets are needed to verify our results and place ever more stringent constraints on planet formation models.« less

The effects of delay duration on visual working memory for orientation.

PubMed

Shin, Hongsup; Zou, Qijia; Ma, Wei Ji

2017-12-01

We used a delayed-estimation paradigm to characterize the joint effects of set size (one, two, four, or six) and delay duration (1, 2, 3, or 6 s) on visual working memory for orientation. We conducted two experiments: one with delay durations blocked, another with delay durations interleaved. As dependent variables, we examined four model-free metrics of dispersion as well as precision estimates in four simple models. We tested for effects of delay time using analyses of variance, linear regressions, and nested model comparisons. We found significant effects of set size and delay duration on both model-free and model-based measures of dispersion. However, the effect of delay duration was much weaker than that of set size, dependent on the analysis method, and apparent in only a minority of subjects. The highest forgetting slope found in either experiment at any set size was a modest 1.14°/s. As secondary results, we found a low rate of nontarget reports, and significant estimation biases towards oblique orientations (but no dependence of their magnitude on either set size or delay duration). Relative stability of working memory even at higher set sizes is consistent with earlier results for motion direction and spatial frequency. We compare with a recent study that performed a very similar experiment.

Cavitational synthesis of nanostructured inorganic materials for enhanced heterogeneous catalysis

NASA Astrophysics Data System (ADS)

Krausz, Ivo Michael

The synthesis of nanostructured inorganic materials by hydrodynamic cavitation processing was investigated. The goal of this work was to develop a general synthesis technique for nanostructured materials with a control over crystallite size in the 1--20 nm range. Materials with crystallite sizes in this range have shown enhanced catalytic activity compared to materials with larger crystallite sizes. Several supported and unsupported inorganic materials were studied to understand the effects of cavitation on crystallite size. Cavitation processing of calcium fluoride resulted in more spherical particles, attached to one another by melted necks. This work produced the first evidence of shock wave heating of nanostructured materials by hydrodynamic cavitation processing. Hydrodynamic cavitation synthesis of various catalytic support materials indicated that their phase composition and purity could be controlled by adjustment of the processing parameters. Zirconia/alumina supports synthesized using hydro-dynamic cavitation and calcined to 1368 K retained a high purity cubic zirconia phase, whereas classically prepared samples showed a phase transformation to monoclinic zirconia. Similarly, the synthesis of alumina resulted in materials with varying Bohmite and Bayerite contents as a function of the process parameters. High temperature calcination resulted in stable alumina supports with varying amounts of delta-, and theta-alumina. Synthesis studies of palladium and silver showed modest variations in crystallite size as a function of cavitation process parameters. Calcination resulted in larger grain materials, indicating a disappearance of intergrain boundaries. Based on these results, a new synthesis method was studied involving controlled agglomeration of small silver crystallites by hydrodynamic cavitation processing, followed by deposition on alumina. The optimal pH, concentration, and processing time for controlling the silver crystallite size in the cavitation equipment were determined using a statistical design of experiments approach. Three series of alumina supported silver catalysts were prepared, with silver weight loadings of 1%, 2%, and 5%. Variation of cavitation processing time between 1--64 min allowed the systematic control of silver crystallite size in the range of 3--19 nm. The preferred oxidation of CO in hydrogen (PROX) was chosen as a catalytic test reaction, because of its increasing importance for fuel cell applications. It was found that the catalytic activity was significantly increased for silver crystallite sizes below 5 nm. This work is the first experimental evidence of independent crystallite size control by hydrodynamic cavitation for alumina supported silver catalysts. The synthesis method involving controlled agglomeration and calcination is a general synthesis procedure that can be used to synthesize a wide range of novel catalysts and advanced materials.

Single-joint outcome measures: preliminary validation of patient-reported outcomes and physical examination.

PubMed

Heald, Alison E; Fudman, Edward J; Anklesaria, Pervin; Mease, Philip J

2010-05-01

To assess the validity, responsiveness, and reliability of single-joint outcome measures for determining target joint (TJ) response in patients with inflammatory arthritis. Patient-reported outcomes (PRO), consisting of responses to single questions about TJ global status on a 100-mm visual analog scale (VAS; TJ global score), function on a 100-mm VAS (TJ function score), and pain on a 5-point Likert scale (TJ pain score) were piloted in 66 inflammatory arthritis subjects in a phase 1/2 clinical study of an intraarticular gene transfer agent and compared to physical examination measures (TJ swelling, TJ tenderness) and validated function questionnaires (Disabilities of the Arm, Shoulder and Hand scale, Rheumatoid Arthritis Outcome Score, and the Health Assessment Questionnaire). Construct validity was assessed by evaluating the correlation between the single-joint outcome measures and validated function questionnaires using Spearman's rank correlation. Responsiveness or sensitivity to change was assessed through calculating effect size and standardized response means (SRM). Reliability of physical examination measures was assessed by determining interobserver agreement. The single-joint PRO were highly correlated with each other and correlated well with validated functional measures. The TJ global score exhibited modest effect size and modest SRM that correlated well with the patient's assessment of response on a 100-mm VAS. Physical examination measures exhibited high interrater reliability, but correlated less well with validated functional measures and the patient's assessment of response. Single-joint PRO, particularly the TJ global score, are simple to administer and demonstrate construct validity and responsiveness in patients with inflammatory arthritis. (ClinicalTrials.gov identifier NCT00126724).

A systematic assessment of goblet cell sampling of the bulbar conjunctiva by impression cytology.

PubMed

Doughty, Michael J

2015-07-01

The purpose of this study was to assess the apparent goblet cell density (GCD) from conjunctival impression cytology (CIC) samples in relation to the number of conjunctival cells collected onto the filters. CIC specimens were collected from the superior-temporal bulbar conjunctiva of 16 pigmented rabbits onto Biopore (Millicell-CM) membranes, fixed with buffered glutaraldehyde and stained with Giemsa. Different numbers of microscope fields of view in each of the specimens were imaged by light microscopy using a 20× magnification objective lens (200× final magnification), and the goblet cells marked and counted. The GCD values/sq. mm were calculated. The same conjunctival region of 3 other rabbits was also prepared for transmission electron microscopy (TEM) by fixation, in situ, with the same buffered glutaraldehyde. Mean values for GCD estimates were found to vary from 399 to 1576 cells/sq. mm, depending on the image sampling and analysis strategy chosen, with the lowest inter-sample variance of around 10% being found if a maximum goblet cell count was taken on substantially multilayered regions of the CIC specimens. Counts of the number of goblet cells per 1000 visible conjunctival epithelial cells yielded a value of close to 90 (range 36-151), with modest inter-sample variability of around 30%. A three or ten 200× microscope field and random sampling strategy yielded mean GCD values between 542 and 670 cells/sq. mm, but with very high intra- and inter-sample variance of at least 60% and sometimes higher than 100%. TEM confirmed the multilayered organization of the conjunctiva and the deeper lying goblet cells. The general use of a goblet cell count as an objective marker for conjunctival normality or health is likely to be highly variable unless a more specific strategy is adopted. Beyond providing details of exactly the counting strategy used, it would be very useful to provide full details of the actual microscope field size used as well as information on the intra-sample variability in goblet cell counts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Variation in obesity among American secondary school students by school and school characteristics.

PubMed

O'Malley, Patrick M; Johnston, Lloyd D; Delva, Jorge; Bachman, Jerald G; Schulenberg, John E

2007-10-01

Body mass index (BMI) is known to vary by individual characteristics, but little is known about whether BMI varies by school and by school characteristics. Nationally representative samples of United States schools and students are used to determine the extent to which BMI and percent of students at or above the 85th percentile of BMI vary by school and by school characteristics. Data from the 1991-2004 Monitoring the Future (MTF) study were analyzed in 2006 and 2007. A relatively small proportion of variance in BMI lies between schools; intraclass correlations are on the order of 3%. Still, this is sufficient variation to provide very different environments for students attending schools that are low versus high in average BMI. There is some modest variation by school type (public, Catholic private, non-Catholic private); school size (number of students in the sampled grade); region of the country; and population density. There is more variation as a function of school socioeconomic status (SES) and racial/ethnic composition of the school. School SES in particular was negatively associated with BMI levels, even after controlling individual-level SES and racial/ethnic status. The residual differences in BMI by school suggest that some characteristic of the school and/or community environment--perhaps cultural factors or peer role modeling or differences in school food, beverage, or physical education policies--facilitate obesity in schools with a high concentration of lower socioeconomic students, beyond individual-level factors.

Personality traits and eating habits in a large sample of Estonians.

PubMed

Mõttus, René; Realo, Anu; Allik, Jüri; Deary, Ian J; Esko, Tõnu; Metspalu, Andres

2012-11-01

Diet has health consequences, which makes knowing the psychological correlates of dietary habits important. Associations between dietary habits and personality traits were examined in a large sample of Estonians (N = 1,691) aged between 18 and 89 years. Dietary habits were measured using 11 items, which grouped into two factors reflecting (a) health aware and (b) traditional dietary patterns. The health aware diet factor was defined by eating more cereal and dairy products, fish, vegetables and fruits. The traditional diet factor was defined by eating more potatoes, meat and meat products, and bread. Personality was assessed by participants themselves and by people who knew them well. The questionnaire used was the NEO Personality Inventory-3, which measures the Five-Factor Model personality broad traits of Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness, along with six facets for each trait. Gender, age and educational level were controlled for. Higher scores on the health aware diet factor were associated with lower Neuroticism, and higher Extraversion, Openness and Conscientiousness (effect sizes were modest: r = .11 to 0.17 in self-ratings, and r = .08 to 0.11 in informant-ratings, ps < 0.01 or lower). Higher scores on the traditional diet factor were related to lower levels of Openness (r = -0.14 and -0.13, p < .001, self- and informant-ratings, respectively). Endorsement of healthy and avoidance of traditional dietary items are associated with people's personality trait levels, especially higher Openness. The results may inform dietary interventions with respect to possible barriers to diet change.

A Low Glycaemic Index Diet in Pregnancy Induces DNA Methylation Variation in Blood of Newborns: Results from the ROLO Randomised Controlled Trial.

PubMed

Geraghty, Aisling A; Sexton-Oates, Alexandra; O'Brien, Eileen C; Alberdi, Goiuri; Fransquet, Peter; Saffery, Richard; McAuliffe, Fionnuala M

2018-04-06

The epigenetic profile of the developing fetus is sensitive to environmental influence. Maternal diet has been shown to influence DNA methylation patterns in offspring, but research in humans is limited. We investigated the impact of a low glycaemic index dietary intervention during pregnancy on offspring DNA methylation patterns using a genome-wide methylation approach. Sixty neonates were selected from the ROLO (Randomised cOntrol trial of LOw glycaemic index diet to prevent macrosomia) study: 30 neonates from the low glycaemic index intervention arm and 30 from the control, whose mothers received no specific dietary advice. DNA methylation was investigated in 771,484 CpG sites in free DNA from cord blood serum. Principal component analysis and linear regression were carried out comparing the intervention and control groups. Gene clustering and pathway analysis were also explored. Widespread variation was identified in the newborns exposed to the dietary intervention, accounting for 11% of the total level of DNA methylation variation within the dataset. No association was found with maternal early-pregnancy body mass index (BMI), infant sex, or birthweight. Pathway analysis identified common influences of the intervention on gene clusters plausibly linked to pathways targeted by the intervention, including cardiac and immune functioning. Analysis in 60 additional samples from the ROLO study failed to replicate the original findings. Using a modest-sized discovery sample, we identified preliminary evidence of differential methylation in progeny of mothers exposed to a dietary intervention during pregnancy.

Chi-Squared Test of Fit and Sample Size-A Comparison between a Random Sample Approach and a Chi-Square Value Adjustment Method.

PubMed

Bergh, Daniel

2015-01-01

Chi-square statistics are commonly used for tests of fit of measurement models. Chi-square is also sensitive to sample size, which is why several approaches to handle large samples in test of fit analysis have been developed. One strategy to handle the sample size problem may be to adjust the sample size in the analysis of fit. An alternative is to adopt a random sample approach. The purpose of this study was to analyze and to compare these two strategies using simulated data. Given an original sample size of 21,000, for reductions of sample sizes down to the order of 5,000 the adjusted sample size function works as good as the random sample approach. In contrast, when applying adjustments to sample sizes of lower order the adjustment function is less effective at approximating the chi-square value for an actual random sample of the relevant size. Hence, the fit is exaggerated and misfit under-estimated using the adjusted sample size function. Although there are big differences in chi-square values between the two approaches at lower sample sizes, the inferences based on the p-values may be the same.

Dietary Chromium Supplementation for Targeted Treatment of Diabetes Patients with Comorbid Depression and Binge Eating

PubMed Central

Brownley, Kimberly A.; Boettiger, Charlotte A.; Young, Laura; Cefalu, William T.

2015-01-01

Dietary chromium supplementation for the treatment of diabetes remains controversial. The prevailing view that chromium supplementation for glucose regulation is unjustified has been based upon prior studies showing mixed, modest-sized effects in patients with type 2 diabetes (T2DM). Based on chromium's potential to improve insulin, dopamine, and serotonin function, we hypothesize that chromium has a greater glucoregulatory effect in individuals who have concurrent disturbances in dopamine and serotonin function – that is, complex patients with comorbid diabetes, depression, and binge eating. We propose, as suggested by the collective data to date, the need to go beyond the “one size fits all” approach to chromium supplementation and put forth a series of experiments designed to link physiological and neurobehavioral processes in the chromium response phenotype. PMID:25838140

Satisfiability Test with Synchronous Simulated Annealing on the Fujitsu AP1000 Massively-Parallel Multiprocessor

NASA Technical Reports Server (NTRS)

Sohn, Andrew; Biswas, Rupak

1996-01-01

Solving the hard Satisfiability Problem is time consuming even for modest-sized problem instances. Solving the Random L-SAT Problem is especially difficult due to the ratio of clauses to variables. This report presents a parallel synchronous simulated annealing method for solving the Random L-SAT Problem on a large-scale distributed-memory multiprocessor. In particular, we use a parallel synchronous simulated annealing procedure, called Generalized Speculative Computation, which guarantees the same decision sequence as sequential simulated annealing. To demonstrate the performance of the parallel method, we have selected problem instances varying in size from 100-variables/425-clauses to 5000-variables/21,250-clauses. Experimental results on the AP1000 multiprocessor indicate that our approach can satisfy 99.9 percent of the clauses while giving almost a 70-fold speedup on 500 processors.

Influence of Modest Endotoxemia on Postoperative Antithrombin Deficiency and Circulating Secretory Immunoglobulin A Levels

PubMed Central

Fujita, Tetsuji; Imai, Takashi; Anazawa, Sadao

2003-01-01

Objective: To evaluate the influence of modest endotoxemia on postoperative antithrombin deficiency and cholestasis. Summary Background Data: It has not been determined whether endotoxin translocation in small amounts is a physiological phenomenon or whether it is a potential health hazard. Methods: Blood endotoxin, antithrombin III (ATIII), secretory immunoglobulin A (sIgA), which was selected as a marker of cholestasis, C-reactive protein (CRP), and α-1-antitrypsin (AAT) concentrations were measured from the 20 patients undergoing curative gastrectomy for gastric cancer preoperatively and postoperatively. Portal and systemic blood samples were taken for the analysis of endotoxin and interleukin-6 (IL-6) concentrations during surgery in these patients. Results: Although plasma endotoxin levels showed a significant increase during surgery, we did not find a correlation with ATIII, sIgA, CRP, and IL-6 levels. Systemic blood endotoxin levels during surgery correlated with a postoperative rise of serum AAT levels. Plasma ATIII levels transiently decreased on the first and third postoperative day, and sIgA levels were shown to increase on the seventh postoperative day. There was a weak relationship between the extent of postoperative endotoxemia and a reduction in ATIII concentrations. Conclusions: The influence of modest endotoxemia on postoperative antithrombin deficiency and cholestasis was limited, and increased translocational endotoxemia during abdominal surgery may be a physiological phenomenon to trigger off an acute-phase protein response. PMID:12894020

Strategic communication related to academic performance: Evidence from China.

PubMed

Zhao, Li; Chen, Lulu; He, Luwei; Heyman, Gail D

2017-09-01

We examined a range of forms of strategic communication relevant to academic performance among 151 seventh- and eleventh-grade adolescents in China. Participants were asked to rate the frequency of their engagement of strategic communication and to evaluate the possible motives for each strategy. The most commonly adopted strategy was to give a vague response about one's own performance, and the predominant motives for strategic communication were the desires to outcompete others, to be prosocial, and to be modest. Males were more likely than females to focus on gaining social approval, and eleventh graders were more likely than seventh graders to focus on being prosocial and modest when engaging in strategic communication. These findings provide insight into the development of strategic communication beyond Western culture. Statement of contribution What is already known on this subject? Adolescents in the West often hide their effort to appear more competent or to gain social acceptance. Little is known about other communication strategies related to academic performance. Little is known about the development of these strategies in non-Western samples. What does this study add? We show that in China, as in Western cultures, children often engage in strategic communication. We demonstrate links between different forms of strategic communication and specific motives. We demonstrate that strategic communication can be motivated by outcompeting others, by being prosocial, and by being modest. © 2017 The British Psychological Society.

Meteorological analysis of the eruption of soufriere in april 1979.

PubMed

Barr, S; Heffter, J L

1982-06-04

Meteorological upper-air data, in conjunction with satellite imagery, lidar light detection and ranging returns, and aircraft sampling, aid in the determination of plume altitude and transport. The estimated trajectories indicate that the ash was transported eastward across the Atlantic to Africa in 3 to 5 days and that there was modest meridional transport as far as 15 degrees poleward during the first week of travel.

A Metabolic Study of Huntington's Disease.

PubMed

Nambron, Rajasree; Silajdžić, Edina; Kalliolia, Eirini; Ottolenghi, Chris; Hindmarsh, Peter; Hill, Nathan R; Costelloe, Seán J; Martin, Nicholas G; Positano, Vincenzo; Watt, Hilary C; Frost, Chris; Björkqvist, Maria; Warner, Thomas T

2016-01-01

Huntington's disease patients have a number of peripheral manifestations suggestive of metabolic and endocrine abnormalities. We, therefore, investigated a number of metabolic factors in a 24-hour study of Huntington's disease gene carriers (premanifest and moderate stage II/III) and controls. Control (n = 15), premanifest (n = 14) and stage II/III (n = 13) participants were studied with blood sampling over a 24-hour period. A battery of clinical tests including neurological rating and function scales were performed. Visceral and subcutaneous adipose distribution was measured using magnetic resonance imaging. We quantified fasting baseline concentrations of glucose, insulin, cholesterol, triglycerides, lipoprotein (a), fatty acids, amino acids, lactate and osteokines. Leptin and ghrelin were quantified in fasting samples and after a standardised meal. We assessed glucose, insulin, growth hormone and cortisol concentrations during a prolonged oral glucose tolerance test. We found no highly significant differences in carbohydrate, protein or lipid metabolism markers between healthy controls, premanifest and stage II/III Huntington's disease subjects. For some markers (osteoprotegerin, tyrosine, lysine, phenylalanine and arginine) there is a suggestion (p values between 0.02 and 0.05) that levels are higher in patients with premanifest HD, but not moderate HD. However, given the large number of statistical tests performed interpretation of these findings must be cautious. Contrary to previous studies that showed altered levels of metabolic markers in patients with Huntington's disease, our study did not demonstrate convincing evidence of abnormalities in any of the markers examined. Our analyses were restricted to Huntington's disease patients not taking neuroleptics, anti-depressants or other medication affecting metabolic pathways. Even with the modest sample sizes studied, the lack of highly significant results, despite many being tested, suggests that the majority of these markers do not differ markedly by disease status.

DNA metabarcoding for diet analysis and biodiversity: A case study using the endangered Australian sea lion (Neophoca cinerea).

PubMed

Berry, Tina E; Osterrieder, Sylvia K; Murray, Dáithí C; Coghlan, Megan L; Richardson, Anthony J; Grealy, Alicia K; Stat, Michael; Bejder, Lars; Bunce, Michael

2017-07-01

The analysis of apex predator diet has the ability to deliver valuable insights into ecosystem health, and the potential impacts a predator might have on commercially relevant species. The Australian sea lion ( Neophoca cinerea ) is an endemic apex predator and one of the world's most endangered pinnipeds. Given that prey availability is vital to the survival of top predators, this study set out to understand what dietary information DNA metabarcoding could yield from 36 sea lion scats collected across 1,500 km of its distribution in southwest Western Australia. A combination of PCR assays were designed to target a variety of potential sea lion prey, including mammals, fish, crustaceans, cephalopods, and birds. Over 1.2 million metabarcodes identified six classes from three phyla, together representing over 80 taxa. The results confirm that the Australian sea lion is a wide-ranging opportunistic predator that consumes an array of mainly demersal fauna. Further, the important commercial species Sepioteuthis australis (southern calamari squid) and Panulirus cygnus (western rock lobster) were detected, but were present in <25% of samples. Some of the taxa identified, such as fish, sharks and rays, clarify previous knowledge of sea lion prey, and some, such as eel taxa and two gastropod species, represent new dietary insights. Even with modest sample sizes, a spatial analysis of taxa and operational taxonomic units found within the scat shows significant differences in diet between many of the sample locations and identifies the primary taxa that are driving this variance. This study provides new insights into the diet of this endangered predator and confirms the efficacy of DNA metabarcoding of scat as a noninvasive tool to more broadly define regional biodiversity.

Association of OPRD1 polymorphisms with heroin dependence in a large case-control series.

PubMed

Nelson, Elliot C; Lynskey, Michael T; Heath, Andrew C; Wray, Naomi; Agrawal, Arpana; Shand, Fiona L; Henders, Anjali K; Wallace, Leanne; Todorov, Alexandre A; Schrage, Andrew J; Madden, Pamela A F; Degenhardt, Louisa; Martin, Nicholas G; Montgomery, Grant W

2014-01-01

Genes encoding the opioid receptors (OPRM1, OPRD1 and OPRK1) are obvious candidates for involvement in risk for heroin dependence. Prior association studies commonly had samples of modest size, included limited single nucleotide polymorphism (SNP) coverage of these genes and yielded inconsistent results. Participants for the current investigation included 1459 heroin-dependent cases ascertained from maintenance clinics in New South Wales, Australia, 1495 unrelated individuals selected from an Australian sample of twins and siblings as not meeting DSM-IV criteria for lifetime alcohol or illicit drug dependence (non-dependent controls) and 531 controls ascertained from economically disadvantaged neighborhoods in proximity to the maintenance clinics. A total of 136 OPRM1, OPRD1 and OPRK1 SNPs were genotyped in this sample. After controlling for admixture with principal components analysis, our comparison of cases to non-dependent controls found four OPRD1 SNPs in fairly high linkage disequilibrium for which adjusted P values remained significant (e.g. rs2236857; OR 1.25; P=2.95×10(-4) ) replicating a previously reported association. A post hoc analysis revealed that the two SNP (rs2236857 and rs581111) GA haplotype in OPRD1 is associated with greater risk (OR 1.68; P=1.41×10(-5) ). No OPRM1 or OPRK1 SNPs reached more than nominal significance. Comparisons of cases to neighborhood controls reached only nominal significance. Our results replicate a prior report providing strong evidence implicating OPRD1 SNPs and, in particular, the two SNP (rs2236857 and rs581111) GA haplotype in liability for heroin dependence. Support was not found for similar association involving either OPRM1 or OPRK1 SNPs. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

Measurement and structural invariance of the US version of the Birth Satisfaction Scale-Revised (BSS-R) in a large sample.

PubMed

Martin, Colin R; Hollins Martin, Caroline J; Burduli, Ekaterina; Barbosa-Leiker, Celestina; Donovan-Batson, Colleen; Fleming, Susan E

2017-08-01

The 10-item Birth Satisfaction Scale-Revised (BSS-R) is being increasingly used internationally. The use of the measure and the concept has gathered traction in the United States following the development of a US version of the tool. A limitation of previous studies of the measurement characteristics of the BSS-R is modest sample size. Unplanned pregnancy is recognised as being associated with a range of negative birth outcomes, but the relationship to birth satisfaction has received little attention, despite the importance of birth satisfaction to a range of postnatal outcomes. The current investigation sought to evaluate the measurement characteristics of the BSS-R in a large postpartum sample. Multiple Groups Confirmatory Factor Analysis (MGCFA) was used to evaluate a series of measurement and structural models of the BSS-R to evaluate fundamental invariance characteristics using planned/unplanned pregnancy status to differentiate groups. Complete data from N=2116 women revealed that the US version of the BSS-R offers an excellent fit to data and demonstrates full measurement and structural invariance. Little difference was observed between women on the basis of planned/unplanned pregnancy stratification on measures of birth satisfaction. The established relationship between unplanned pregnancy and negative perinatal outcomes was not found to extend to birth satisfaction in the current study. The BSS-R demonstrated exemplary measurement and structural invariance characteristics. The current study strongly supports the use of the US version of the BSS-R to compare birth satisfaction across different groups of women with theoretical and measurement confidence. Copyright © 2016 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

Optical Observations of GEO Debris with Two Telescopes

NASA Technical Reports Server (NTRS)

Seitzer, P.; Abercromby, K.; Rodriguez, H.; Barker, E.

2007-01-01

For several years, the Michigan Orbital DEbris Survey Telescope (MODEST), the University of Michigan s 0.6/0.9-m Schmidt telescope on Cerro Tololo Inter-American Observatory in Chile has been used to survey the debris population at GEO in the visible regime. Magnitudes, positions, and angular rates are determined for GEO objects as they move across the telescope s field-of-view (FOV) during a 5-minute window. This short window of time is not long enough to determine a full six parameter orbit so usually a circular orbit is assumed. A longer arc of time is necessary to determine eccentricity and to look for changes in the orbit with time. MODEST can follow objects in real-time, but only at the price of stopping survey operations. A second telescope would allow for longer arcs of orbit to obtain the full six orbital parameters, as well as assess the changes over time. An additional benefit of having a second telescope is the capability of obtaining BVRI colors of the faint targets, aiding efforts to determine the material type of faint debris. For 14 nights in March 2007, two telescopes were used simultaneously to observe the GEO debris field. MODEST was used exclusively in survey mode. As objects were detected, they were handed off in near real-time to the Cerro Tololo 0.9-m telescope for follow-up observations. The goal was to determine orbits and colors for all objects fainter than R = 15th magnitude (corresponds to 1 meter in size assuming a 0.2 albedo) detected by MODEST. The hand-off process was completely functional during the final eight nights and follow-ups for objects from night-to-night were possible. The cutoff magnitude level of 15th was selected on the basis of an abrupt change in the observed angular rate distribution in the MODEST surveys. Objects brighter than 15th magnitude tend to lie on a well defined locus in the angular rate plane (and have orbits in the catalog), while fainter objects fill the plane almost uniformly. We need to determine full six-parameter orbits to investigate what causes this change in observed angular rates. Are these faint objects either the same population of high area-to-mass (A/M) objects on eccentric orbits as discovered by the ESA Space Debris Telescope (Schildknecht, et al. 2004), or are they just normal debris from breakups in GEO?

A measurement error model for physical activity level as measured by a questionnaire with application to the 1999-2006 NHANES questionnaire.

PubMed

Tooze, Janet A; Troiano, Richard P; Carroll, Raymond J; Moshfegh, Alanna J; Freedman, Laurence S

2013-06-01

Systematic investigations into the structure of measurement error of physical activity questionnaires are lacking. We propose a measurement error model for a physical activity questionnaire that uses physical activity level (the ratio of total energy expenditure to basal energy expenditure) to relate questionnaire-based reports of physical activity level to true physical activity levels. The 1999-2006 National Health and Nutrition Examination Survey physical activity questionnaire was administered to 433 participants aged 40-69 years in the Observing Protein and Energy Nutrition (OPEN) Study (Maryland, 1999-2000). Valid estimates of participants' total energy expenditure were also available from doubly labeled water, and basal energy expenditure was estimated from an equation; the ratio of those measures estimated true physical activity level ("truth"). We present a measurement error model that accommodates the mixture of errors that arise from assuming a classical measurement error model for doubly labeled water and a Berkson error model for the equation used to estimate basal energy expenditure. The method was then applied to the OPEN Study. Correlations between the questionnaire-based physical activity level and truth were modest (r = 0.32-0.41); attenuation factors (0.43-0.73) indicate that the use of questionnaire-based physical activity level would lead to attenuated estimates of effect size. Results suggest that sample sizes for estimating relationships between physical activity level and disease should be inflated, and that regression calibration can be used to provide measurement error-adjusted estimates of relationships between physical activity and disease.

Scalability and Portability of Two Parallel Implementations of ADI

NASA Technical Reports Server (NTRS)

Phung, Thanh; VanderWijngaart, Rob F.

1994-01-01

Two domain decompositions for the implementation of the NAS Scalar Penta-diagonal Parallel Benchmark on MIMD systems are investigated, namely transposition and multi-partitioning. Hardware platforms considered are the Intel iPSC/860 and Paragon XP/S-15, and clusters of SGI workstations on ethernet, communicating through PVM. It is found that the multi-partitioning strategy offers the kind of coarse granularity that allows scaling up to hundreds of processors on a massively parallel machine. Moreover, efficiency is retained when the code is ported verbatim (save message passing syntax) to a PVM environment on a modest size cluster of workstations.

The Power of Low Back Pain Trials: A Systematic Review of Power, Sample Size, and Reporting of Sample Size Calculations Over Time, in Trials Published Between 1980 and 2012.

PubMed

Froud, Robert; Rajendran, Dévan; Patel, Shilpa; Bright, Philip; Bjørkli, Tom; Eldridge, Sandra; Buchbinder, Rachelle; Underwood, Martin

2017-06-01

A systematic review of nonspecific low back pain trials published between 1980 and 2012. To explore what proportion of trials have been powered to detect different bands of effect size; whether there is evidence that sample size in low back pain trials has been increasing; what proportion of trial reports include a sample size calculation; and whether likelihood of reporting sample size calculations has increased. Clinical trials should have a sample size sufficient to detect a minimally important difference for a given power and type I error rate. An underpowered trial is one within which probability of type II error is too high. Meta-analyses do not mitigate underpowered trials. Reviewers independently abstracted data on sample size at point of analysis, whether a sample size calculation was reported, and year of publication. Descriptive analyses were used to explore ability to detect effect sizes, and regression analyses to explore the relationship between sample size, or reporting sample size calculations, and time. We included 383 trials. One-third were powered to detect a standardized mean difference of less than 0.5, and 5% were powered to detect less than 0.3. The average sample size was 153 people, which increased only slightly (∼4 people/yr) from 1980 to 2000, and declined slightly (∼4.5 people/yr) from 2005 to 2011 (P < 0.00005). Sample size calculations were reported in 41% of trials. The odds of reporting a sample size calculation (compared to not reporting one) increased until 2005 and then declined (Equation is included in full-text article.). Sample sizes in back pain trials and the reporting of sample size calculations may need to be increased. It may be justifiable to power a trial to detect only large effects in the case of novel interventions. 3.

Alpha Elements' Effects on Planet Formation and the Hunt for Extragalactic Planets

NASA Astrophysics Data System (ADS)

Penny, Matthew; Rodriguez, Joseph E.; Beatty, Thomas; Zhou, George

2018-01-01

A star's likelihood of hosting a giant planet is well known to be strongly dependent on metallicity. However, little is known about what elements cause this correlation (e.g. bulk metals, iron, or alpha elements such as silicon and oxygen). This is likely because most planet searches target stars in the Galactic disk, and due to Galactic chemical evolution, alpha element abundances are themselves correlated with metallicity within a population. We investigate the feasibility of simultaneous transiting planet search towards the alpha-poor Sagittarius dwarf galaxy and alpha-rich Galactic bulge in a single field of view of DECam, that would enable a comparative study of planet frequency over an [alpha/Fe] baseline of ~0.4 dex. We show that a modestly sized survey could detect planet candidates in both populations, but that false positive rejection in Sgr Dwarf may be prohibitively expensive. Conversely, two-filter survey observations alone would be sufficient to rule out a large fraction of bulge false positives, enabling statistical validation of candidates with a modest follow-up investment. Although over a shorter [alpha/Fe] baseline, this survey would provide a test of whether it is alpha or iron that causes the planet metallicity correlation.

Buses, Cars, Bicycles and Walkers: The Influence of the Type of Human Transport on the Flight Responses of Waterbirds

PubMed Central

McLeod, Emily M.; Guay, Patrick-Jean; Taysom, Alice J.; Robinson, Randall W.; Weston, Michael A.

2013-01-01

One way to manage disturbance to waterbirds in natural areas where humans require access is to promote the occurrence of stimuli for which birds tolerate closer approaches, and so cause fewer responses. We conducted 730 experimental approaches to 39 species of waterbird, using five stimulus types (single walker, three walkers, bicycle, car and bus) selected to mimic different human management options available for a controlled access, Ramsar-listed wetland. Across species, where differences existed (56% of 25 cases), motor vehicles always evoked shorter flight-initiation distances (FID) than humans on foot. The influence of stimulus type on FID varied across four species for which enough data were available for complete cross-stimulus analysis. All four varied FID in relation to stimuli, differing in 4 to 7 of 10 possible comparisons. Where differences occurred, the effect size was generally modest, suggesting that managing stimulus type (e.g. by requiring people to use vehicles) may have species-specific, modest benefits, at least for the waterbirds we studied. However, different stimulus types have different capacities to reduce the frequency of disturbance (i.e. by carrying more people) and vary in their capacity to travel around important habitat. PMID:24367498

Assessment of Teaching Approaches in an Introductory Astronomy College Classroom

NASA Astrophysics Data System (ADS)

Alexander, William R.

In recent years, there have been calls from the astronomy education research community for the increased use of learner-centered approaches to teaching, and systematic assessments of various teaching approaches using such tools as the Astronomy Diagnostic Test 2.0 (ADT 2.0). The research presented is a response to both calls. The ADT 2.0 was used in a modified form to obtain baseline assessments of introductory college astronomy classes that were taught in a traditional, mostly didactic manner. The ADT 2.0 (modified) was administered both before and after the completion of the courses. The courses were then altered to make modest use of learner-centered lecture tutorials. The ADT 2.0 (modified) was again administered before and after completion of the modified courses. Overall, the modest learner-centered approach showed mixed statistical results, with an increase in effect size (from medium to large), but no change in normalized gain index (both were low). Additionally, a mathematically rigorous approach showed no statistically significant improvements in conceptual understanding compared with a mathematically nonrigorous approach. This study will interpret the results from a variety of perspectives. The overall implementation of the lecture tutorials and their implications for teaching will also be discussed.

Radar systems for the water resources mission. Volume 4: Appendices E-I

NASA Technical Reports Server (NTRS)

Moore, R. K.; Claassen, J. P.; Erickson, R. L.; Fong, R. K. T.; Hanson, B. C.; Komen, M. J.; Mcmillan, S. B.; Parashar, S. K.

1976-01-01

The use of a scanning antenna beam for a synthetic aperture system was examined. When the resolution required was modest, the radar did not use all the time the beam was passing a given point on the ground to build a synthetic aperture, so time was available to scan the beam to other positions and build several images at different ranges. The scanning synthetic-aperture radar (SCANSAR) could achieve swathwidths of well over 100 km with modest antenna size. Design considerations for a SCANSAR for hydrologic parameter observation are presented. Because of the high sensitivity to soil moisture at angles of incidence near vertical, a 7 to 22 deg swath was considered for that application. For snow and ice monitoring, a 22 to 37 deg scan was used. Frequencies from X-band to L-band were used in the design studies, but the proposed system operated in C-band at 4.75 GHz. It achieved an azimuth resolution of about 50 meters at all angles, with a range resolution varying from 150 meters at 7 deg to 31 meters at 37 deg. The antenna required an aperture of 3 x 4.16 meters, and the average transmitter power was under 2 watts.

Great-earthquake paleogeodesy and tsunamis of the past 2000 years at Alsea Bay, central Oregon coast, USA

USGS Publications Warehouse

Nelson, A.R.; Sawai, Y.; Jennings, A.E.; Bradley, L.A.; Gerson, L.; Sherrod, B.L.; Sabean, J.; Horton, B.P.

2008-01-01

The width of plate-boundary fault rupture at the Cascadia subduction zone, a dimension related to earthquake magnitude, remains uncertain because of the lack of quantitative information about land-level movements during past great-earthquake deformation cycles. Beneath a marsh at Alsea Bay, on the central Oregon coast, four sheets of tsunami-deposited sand blanket contacts between tidal mud and peat. Radiocarbon ages for the sheets match ages for similar evidence of regional coseismic subsidence and tsunamis during four of Cascadia's great earthquakes. Barring rapid, unrecorded postseismic uplift, reconstruction of changes in land level from core samples using diatom and foraminiferal transfer functions includes modest coseismic subsidence (0.4??0.2 m) during the four earthquakes. Interpretation is complicated, however, by the 30-38% of potentially unreliable transfer function values from samples with poor analogs in modern diatom and foraminiferal assemblages. Reconstructions of coseismic subsidence using good-analog samples range from 0.46??0.12 to 0.09??0.20 m showing greater variability than implied by sample-specific errors. From apparent high rates of land uplift following subsidence and tsunamis, we infer that postseismic rebound caused by slip on deep parts of the plate boundary and (or) viscoelastic stress relaxation in the upper plate may be almost as large as coseismic subsidence. Modest coseismic subsidence 100 km landward of the deformation front implies that plate-boundary ruptures in central Oregon were largely offshore. Ruptures may have been long and narrow during earthquakes near magnitude 9, as suggested for the AD 1700 earthquake, or of smaller and more variable dimensions and magnitudes. ?? 2008 Elsevier Ltd. All rights reserved.

Improved spatial resolution in PET scanners using sampling techniques

PubMed Central

Surti, Suleman; Scheuermann, Ryan; Werner, Matthew E.; Karp, Joel S.

2009-01-01

Increased focus towards improved detector spatial resolution in PET has led to the use of smaller crystals in some form of light sharing detector design. In this work we evaluate two sampling techniques that can be applied during calibrations for pixelated detector designs in order to improve the reconstructed spatial resolution. The inter-crystal positioning technique utilizes sub-sampling in the crystal flood map to better sample the Compton scatter events in the detector. The Compton scatter rejection technique, on the other hand, rejects those events that are located further from individual crystal centers in the flood map. We performed Monte Carlo simulations followed by measurements on two whole-body scanners for point source data. The simulations and measurements were performed for scanners using scintillators with Zeff ranging from 46.9 to 63 for LaBr3 and LYSO, respectively. Our results show that near the center of the scanner, inter-crystal positioning technique leads to a gain of about 0.5-mm in reconstructed spatial resolution (FWHM) for both scanner designs. In a small animal LYSO scanner the resolution improves from 1.9-mm to 1.6-mm with the inter-crystal technique. The Compton scatter rejection technique shows higher gains in spatial resolution but at the cost of reduction in scanner sensitivity. The inter-crystal positioning technique represents a modest acquisition software modification for an improvement in spatial resolution, but at a cost of potentially longer data correction and reconstruction times. The Compton scatter rejection technique, while also requiring a modest acquisition software change with no increased data correction and reconstruction times, will be useful in applications where the scanner sensitivity is very high and larger improvements in spatial resolution are desirable. PMID:19779586

New ultra metal-poor stars from SDSS: follow-up GTC medium-resolution spectroscopy

NASA Astrophysics Data System (ADS)

Aguado, D. S.; Allende Prieto, C.; González Hernández, J. I.; Rebolo, R.; Caffau, E.

2017-07-01

Context. The first generation of stars formed in the Galaxy left behind the chemical signatures of their nucleosynthesis in the interstellar medium, visible today in the atmospheres of low-mass stars that formed afterwards. Sampling the chemistry of those low-mass provides insight into the first stars. Aims: We aim to increase the samples of stars with extremely low metal abundances, identifying ultra metal-poor stars from spectra with modest spectral resolution and signal-to-noise ratio (S/N). Achieving this goal involves deriving reliable metallicities and carbon abundances from such spectra. Methods: We carry out follow-up observations of faint, V > 19, metal-poor candidates selected from SDSS spectroscopy and observed with the Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy (OSIRIS) at GTC. The SDSS and follow-up OSIRIS spectra were analyzed using the FERRE code to derive effective temperatures, surface gravities, metallicities and carbon abundances. In addition, a well-known extremely metal-poor star has been included in our sample to calibrate the analysis methodology. Results: We observed and analyzed five metal-poor candidates from modest-quality SDSS spectra. All stars in our sample have been confirmed as extremely metal-poor stars, in the [Fe/H] < -3.3 regime. We report the recognition of J173403+644632, a carbon-enhanced ultra metal-poor dwarf star with [Fe/H] = -4.3 and [C/Fe] = + 3.1. Based on observations made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias, on the island of La Palma. Programme ID GTC2E-16A and ID GTC65-16B.

Publication Bias in Psychology: A Diagnosis Based on the Correlation between Effect Size and Sample Size

PubMed Central

Kühberger, Anton; Fritz, Astrid; Scherndl, Thomas

2014-01-01

Background The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias. Methods We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values. Results We found a negative correlation of r = −.45 [95% CI: −.53; −.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings. Conclusion The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology. PMID:25192357

Publication bias in psychology: a diagnosis based on the correlation between effect size and sample size.

PubMed

Kühberger, Anton; Fritz, Astrid; Scherndl, Thomas

2014-01-01

The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias. We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values. We found a negative correlation of r = -.45 [95% CI: -.53; -.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings. The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology.

Visual search for arbitrary objects in real scenes.

PubMed

Wolfe, Jeremy M; Alvarez, George A; Rosenholtz, Ruth; Kuzmova, Yoana I; Sherman, Ashley M

2011-08-01

How efficient is visual search in real scenes? In searches for targets among arrays of randomly placed distractors, efficiency is often indexed by the slope of the reaction time (RT) × Set Size function. However, it may be impossible to define set size for real scenes. As an approximation, we hand-labeled 100 indoor scenes and used the number of labeled regions as a surrogate for set size. In Experiment 1, observers searched for named objects (a chair, bowl, etc.). With set size defined as the number of labeled regions, search was very efficient (~5 ms/item). When we controlled for a possible guessing strategy in Experiment 2, slopes increased somewhat (~15 ms/item), but they were much shallower than search for a random object among other distinctive objects outside of a scene setting (Exp. 3: ~40 ms/item). In Experiments 4-6, observers searched repeatedly through the same scene for different objects. Increased familiarity with scenes had modest effects on RTs, while repetition of target items had large effects (>500 ms). We propose that visual search in scenes is efficient because scene-specific forms of attentional guidance can eliminate most regions from the "functional set size" of items that could possibly be the target.

Optimum sample size allocation to minimize cost or maximize power for the two-sample trimmed mean test.

PubMed

Guo, Jiin-Huarng; Luh, Wei-Ming

2009-05-01

When planning a study, sample size determination is one of the most important tasks facing the researcher. The size will depend on the purpose of the study, the cost limitations, and the nature of the data. By specifying the standard deviation ratio and/or the sample size ratio, the present study considers the problem of heterogeneous variances and non-normality for Yuen's two-group test and develops sample size formulas to minimize the total cost or maximize the power of the test. For a given power, the sample size allocation ratio can be manipulated so that the proposed formulas can minimize the total cost, the total sample size, or the sum of total sample size and total cost. On the other hand, for a given total cost, the optimum sample size allocation ratio can maximize the statistical power of the test. After the sample size is determined, the present simulation applies Yuen's test to the sample generated, and then the procedure is validated in terms of Type I errors and power. Simulation results show that the proposed formulas can control Type I errors and achieve the desired power under the various conditions specified. Finally, the implications for determining sample sizes in experimental studies and future research are discussed.

The mitochondrial genome of the legume Vigna radiata and the analysis of recombination across short mitochondrial repeats.

PubMed

Alverson, Andrew J; Zhuo, Shi; Rice, Danny W; Sloan, Daniel B; Palmer, Jeffrey D

2011-01-20

The mitochondrial genomes of seed plants are exceptionally fluid in size, structure, and sequence content, with the accumulation and activity of repetitive sequences underlying much of this variation. We report the first fully sequenced mitochondrial genome of a legume, Vigna radiata (mung bean), and show that despite its unexceptional size (401,262 nt), the genome is unusually depauperate in repetitive DNA and "promiscuous" sequences from the chloroplast and nuclear genomes. Although Vigna lacks the large, recombinationally active repeats typical of most other seed plants, a PCR survey of its modest repertoire of short (38-297 nt) repeats nevertheless revealed evidence for recombination across all of them. A set of novel control assays showed, however, that these results could instead reflect, in part or entirely, artifacts of PCR-mediated recombination. Consequently, we recommend that other methods, especially high-depth genome sequencing, be used instead of PCR to infer patterns of plant mitochondrial recombination. The average-sized but repeat- and feature-poor mitochondrial genome of Vigna makes it ever more difficult to generalize about the factors shaping the size and sequence content of plant mitochondrial genomes.

Enhanced gel formation in binary mixtures of nanocolloids with short-range attraction

NASA Astrophysics Data System (ADS)

Harden, James L.; Guo, Hongyu; Bertrand, Martine; Shendruk, Tyler N.; Ramakrishnan, Subramanian; Leheny, Robert L.

2018-01-01

Colloidal suspensions transform between fluid and disordered solid states as parameters such as the colloid volume fraction and the strength and nature of the colloidal interactions are varied. Seemingly subtle changes in the characteristics of the colloids can markedly alter the mechanical rigidity and flow behavior of these soft composite materials. This sensitivity creates both a scientific challenge and an opportunity for designing suspensions for specific applications. In this paper, we report a novel mechanism of gel formation in mixtures of weakly attractive nanocolloids with modest size ratio. Employing a combination of x-ray photon correlation spectroscopy, rheometry, and molecular dynamics simulations, we find that gels are stable at remarkably weaker attraction in mixtures with size ratio near two than in the corresponding monodisperse suspensions. In contrast with depletion-driven gelation at larger size ratio, gel formation in the mixtures is triggered by microphase demixing of the species into dense regions of immobile smaller colloids surrounded by clusters of mobile larger colloids that is not predicted by mean-field thermodynamic considerations. These results point to a new route for tailoring nanostructured colloidal solids through judicious combination of interparticle interaction and size distribution.

High-Pressure Study of Perovskites and Postperovskites in the (Mg,Fe)GeO 3 System

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

Stan, Camelia V.; Dutta, Rajkrishna; Cava, Robert J.

2017-06-22

The effect of incorporation of Fe 2+ on the perovskite (Pbnm) and postperovskite (Cmcm) structures was investigated in the (Mg,Fe)GeO 3 system at high pressures and temperatures using laser-heated diamond anvil cell and synchrotron X-ray diffraction. Samples with compositions of Mg# ≥ 48 were shown to transform to the perovskite (~30 GPa and ~1500 K) and postperovskite (>55 GPa, ~1600–1800 K) structures. Compositions with Mg# ≥ 78 formed single-phase perovskite and postperovskite, whereas those with Mg# < 78 showed evidence for partial decomposition. The incorporation of Fe into the perovskite structure causes a decrease in octahedral distortion as well asmore » a modest decrease in bulk modulus (K 0) and a modest increase in zero-pressure volume (V 0). It also leads to a decrease in the perovskite-to-postperovskite phase transition pressure by ~9.5 GPa over compositions from Mg#78 to Mg#100.« less

Association between stressful life events and psychotic experiences in adolescence: evidence for gene-environment correlations.

PubMed

Shakoor, Sania; Zavos, Helena M S; Haworth, Claire M A; McGuire, Phillip; Cardno, Alastair G; Freeman, Daniel; Ronald, Angelica

2016-06-01

Stressful life events (SLEs) are associated with psychotic experiences. SLEs might act as an environmental risk factor, but may also share a genetic propensity with psychotic experiences. To estimate the extent to which genetic and environmental factors influence the relationship between SLEs and psychotic experiences. Self- and parent reports from a community-based twin sample (4830 16-year-old pairs) were analysed using structural equation model fitting. SLEs correlated with positive psychotic experiences (r = 0.12-0.14, all P<0.001). Modest heritability was shown for psychotic experiences (25-57%) and dependent SLEs (32%). Genetic influences explained the majority of the modest covariation between dependent SLEs and paranoia and cognitive disorganisation (bivariate heritabilities 74-86%). The relationship between SLEs and hallucinations and grandiosity was explained by both genetic and common environmental effects. Further to dependent SLEs being an environmental risk factor, individuals may have an underlying genetic propensity increasing their risk of dependent SLEs and positive psychotic experiences. © The Royal College of Psychiatrists 2016.

Combining nonoverlap and trend for single-case research: Tau-U.

PubMed

Parker, Richard I; Vannest, Kimberly J; Davis, John L; Sauber, Stephanie B

2011-06-01

A new index for analysis of single-case research data was proposed, Tau-U, which combines nonoverlap between phases with trend from within the intervention phase. In addition, it provides the option of controlling undesirable Phase A trend. The derivation of Tau-U from Kendall's Rank Correlation and the Mann-Whitney U test between groups is demonstrated. The equivalence of trend and nonoverlap is also shown, with supportive citations from field leaders. Tau-U calculations are demonstrated for simple AB and ABA designs. Tau-U is then field tested on a sample of 382 published data series. Controlling undesirable Phase A trend caused only a modest change from nonoverlap. The inclusion of Phase B trend yielded more modest results than simple nonoverlap. The Tau-U score distribution did not show the artificial ceiling shown by all other nonoverlap techniques. It performed reasonably well with autocorrelated data. Tau-U shows promise for single-case applications, but further study is desirable. Copyright © 2011. Published by Elsevier Ltd.

Magnetic Surfaces, Thin Films, and Multilayers

DTIC Science & Technology

1992-01-01

investigations %as the cleaved ((00)I) face of highly oriented pyrolytic graphite ( HOPG ). This surface is inert in air and is easily imaged with the STM[83-86...Parkin IBM Almaden Research Center, San Jose, California, U.S.A. Herbert Hopster University of California -Irvine, Irvine, California, U.S.A. Jean...magnetic fields (typically 10 to 100 kOe). For polycrystalline samples and at normal temperatures more modest increases, typically of a factor of 2 to 10

Michigan Orbital DEbris Survey Telescope Observations of the Geosynchronous Orbital Debris Environment. Observing Years: 2007-2009

NASA Technical Reports Server (NTRS)

Abercromby, K. J.; Seitzer, P.; Cowardin, H. M.; Barker, E. S.; Matney, M. J.

2011-01-01

NASA uses the Michigan Orbital DEbris Survey Telescope (MODEST), the University of Michigan's 0.61-m aperture Curtis-Schmidt telescope at the Cerro Tololo Inter-American Observatory in Chile, to help characterize the debris environment in geosynchronous orbit; this began in February 2001 and continues to the present day. Detected objects that are found to be on the U.S. Space Surveillance Network cataloged objects list are termed correlated targets (CTs), while those not found on the list are called uncorrelated targets (UCTs). This Johnson Space Center report provides details of observational and data-reduction processes for the entire MODEST dataset acquired in calendar years (CYs) 2007, 2008, and 2009. Specifically, this report describes the collection and analysis of 36 nights of data collected in CY 2007, 43 nights of data collected in CY 2008, and 43 nights of data collected in CY 2009. MODEST is equipped with a 2048 x 2048-pixel charged coupled device camera with a 1.3 by 1.3 deg field of view. This system is capable of detecting objects fainter than 18th magnitude (R filter) using a 5-s integration. This corresponds to a 20-cm diameter, 0.175-albedo object at 36,000 km altitude assuming a diffuse Lambertian phase function. The average number of detections each night over all 3 years was 26. The percentage of this number that represented the UCT population ranged from 34% to 18%, depending on the observing strategy and the field center location. Due to the short orbital arc over which observations are made, the eccentricity of the object s orbit is extremely difficult to measure accurately. Therefore, a circular orbit was assumed when calculating the orbital elements. A comparison of the measured inclination (INC), right ascension of ascending node (RAAN), and mean motion to the quantities for CTs from the U.S. Space Surveillance Network shows acceptable errors. This analysis lends credibility to the determination of the UCT orbital distributions. Figure 1 shows the size distribution of 3,143 objects detected in the data processed for CYs 2007, 2008, and 2009. The actual peak of the absolute magnitude distribution for the functional correlated targets is 10th magnitude, whereas the peak was 11th magnitude in 2002 2003 and 10th magnitude for 2004-2006. An absolute magnitude of 10.5 corresponds to objects with average diameters of 6.3 m, assuming an albedo of 0.175 and a diffuse Lambertian phase function. This result generally agrees with the known sizes of intact satellites. The absolute magnitude distribution for the UCTs is broad, but starts to roll off near 25 cm diameter or 17.5 magnitude. This roll off in the distribution reflects the detection capability of MODEST, not the true nature of the population. The true population is believed to continue at the same slope through fainter magnitudes based on comparisons with the LEO break-up law.

Comparison of Orbital Parameters for GEO Debris Predicted by LEGEND and Observed by MODEST: Can Sources of Orbital Debris be Identified?

NASA Technical Reports Server (NTRS)

Barker, Edwin S.; Matney, M. J.; Liou, J.-C.; Abercromby, K. J.; Rodriquez, H. M.; Seitzer, P.

2006-01-01

Since 2002 the National Aeronautics and Space Administration (NASA) has carried out an optical survey of the debris environment in the geosynchronous Earth-orbit (GEO) region with the Michigan Orbital Debris Survey Telescope (MODEST) in Chile. The survey coverage has been similar for 4 of the 5 years allowing us to follow the orbital evolution of Correlated Targets (CTs), both controlled and un-controlled objects, and Un-Correlated Targets (UCTs). Under gravitational perturbations the distributions of uncontrolled objects, both CTs and UCTs, in GEO orbits will evolve in predictable patterns, particularly evident in the inclination and right ascension of the ascending node (RAAN) distributions. There are several clusters (others have used a "cloud" nomenclature) in observed distributions that show evolution from year to year in their inclination and ascending node elements. However, when MODEST is in survey mode (field-of-view approx.1.3deg) it provides only short 5-8 minute orbital arcs which can only be fit under the assumption of a circular orbit approximation (ACO) to determine the orbital parameters. These ACO elements are useful only in a statistical sense as dedicated observing runs would be required to obtain sufficient orbital coverage to determine a set of accurate orbital elements and then to follow their evolution. Identification of the source(s) for these "clusters of UCTs" would be advantageous to the overall definition of the GEO orbital debris environment. This paper will set out to determine if the ACO elements can be used to in a statistical sense to identify the source of the "clustering of UCTs" roughly centered on an inclination of 12deg and a RAAN of 345deg. The breakup of the Titan 3C-4 transtage on February 21, 1992 has been modeled using NASA s LEGEND (LEO-to-GEO Environment Debris) code to generate a GEO debris cloud. Breakup fragments are created based on the NASA Standard Breakup Model (including fragment size, area-to-mass (A/M), and delta-V distributions). Once fragments are created, they are propagated forward in time with a subroutine GEOPROP. Perturbations included in GEOPROP are those due to solar/lunar gravity, radiation pressure, and major geopotential terms. The question to be addressed: are the UCTs detected by MODEST in this inclination/RAAN region related to the Titan 3C-4 breakup? Discussion will include the observational biases in attempting to detect a specific, uncontrolled target during given observing session. These restrictions include: (1) the length of the observing session which is 8 hours or less at any given date or declination; (2) the assumption of ACO elements for detected object when the breakup model predicts debris with non-zero eccentricities; (3) the size and illumination or brightness of the debris predicted by the model and the telescope/sky limiting magnitude.

Novel strategy for diameter-selective separation and functionalization of single-wall carbon nanotubes.

PubMed

Tromp, R M; Afzali, A; Freitag, M; Mitzi, D B; Chen, Zh

2008-02-01

The problem of separating single-wall carbon nanotubes (CNTs) by diameter and/or chirality is one of the greatest impediments toward the widespread application of these promising materials in nanoelectronics. In this paper, we describe a novel physical-chemical method for diameter-selective CNT separation that is both simple and effective and that allows up-scaling to large volumes at modest cost. Separation is based on size-selective noncovalent matching of an appropriate anchor molecule to the wall of the CNT, enabling suspension of the CNTs in solvents in which they would otherwise not be soluble. We demonstrate size-selective separation in the 1-2 nm diameter range using easily synthesized oligo-acene adducts as a diameter-selective molecular anchor. CNT field effect transistors fabricated from diameter-selected CNTs show markedly improved electrical properties as compared to nonselected CNTs.

Mobile technology boosts the effectiveness of psychotherapy and behavioral interventions: a meta-analysis.

PubMed

Lindhiem, Oliver; Bennett, Charles B; Rosen, Dana; Silk, Jennifer

2015-11-01

We conducted a meta-analysis on the effects of mobile technology on treatment outcome for psychotherapy and other behavioral interventions. Our search of the literature resulted in 26 empirical articles describing 25 clinical trials testing the benefits of smartphone applications, personal digital assistants (PDAs), or text messaging systems either to supplement treatment or substitute for direct contact with a clinician. Overall, mobile technology use was associated with superior treatment outcome across all study designs and control conditions, effect size (ES) = .34, p < .0001. For the subset of 10 studies that looked specifically at the added benefit of mobile technology using a rigorous "Treatment" versus "Treatment + Mobile" design, effect sizes were only slightly more modest (ES = .27) and still significant (p < .05). Overall, the results support the role of mobile technology for the delivery of psychotherapy and other behavioral interventions. © The Author(s) 2015.

Improving nutrition and physical activity in the workplace: a meta-analysis of intervention studies.

PubMed

Hutchinson, Amanda D; Wilson, Carlene

2012-06-01

A comprehensive search of the literature for studies examining physical activity or nutrition interventions in the workplace, published between 1999 and March 2009, was conducted. This search identified 29 relevant studies. Interventions were grouped according to the theoretical framework on which the interventions were based (e.g. education, cognitive-behavioural, motivation enhancement, social influence, exercise). Weighted Cohen's d effect sizes, percentage overlap statistics, confidence intervals and fail safe Ns were calculated. Most theoretical approaches were associated with small effects. However, large effects were found for some measures of interventions using motivation enhancement. Effect sizes were larger for studies focusing on one health behaviour and for randomized controlled trials. The workplace is a suitable environment for making modest changes in the physical activity, nutrition and health of employees. Further research is necessary to determine whether these changes can be maintained in the long term.

Job location decisions of pharmacy graduates in British Columbia.

PubMed

Pearson, Marion L; Andres, Lesley

2010-05-12

To determine the factors influencing pharmacy graduates' selection of their first professional job location. A survey was conducted of the 2007 graduating class of the University of British Columbia, examining hometown location, community and workplace factors, personal relationships, financial factors, and leisure activities. Responses were analyzed to determine whether community size or demographic characteristics affected the degree to which each factor influenced the job location decision. The majority of graduates moved from their hometowns to larger communities, mainly to the largest city in British Columbia. Most of those taking jobs in rural and remote communities grew up in or near those communities, and were more influenced by community size and anticipated working conditions, and less influenced by access to cultural and social activities, than their urban counterparts. The admission of students from rural and remote communities is modestly effective in ensuring a supply of pharmacists for these areas.

Adaption from LWIR to visible wavebands of methods to describe the population of GEO belt debris

NASA Astrophysics Data System (ADS)

Meng, Kevin; Murray-Krezan, Jeremy; Seitzer, Patrick

2018-05-01

Prior efforts to characterize the number of GEO belt debris objects by statistically analyzing the distribution of debris as a function of size have relied on techniques unique to infrared measurements of the debris. Specifically the infrared measurement techniques permitted inference of the characteristic size of the debris. This report describes a method to adapt the previous techniques and measurements to visible wavebands. Results will be presented using data from a NASA optical, visible band survey of objects near the geosynchronous orbit, GEO belt. This survey used the University of Michigan's 0.6-m Curtis-Schmidt telescope, Michigan Orbital DEbris Survey Telescope (MODEST), located at Cerro Tololo Inter-American Observatory in Chile. The system is equipped with a scanning CCD with a field of view of 1.6°×1.6°, and can detect objects smaller than 20 cm diameter at GEO.

Miniature Extreme Ultraviolet Solar Radiometers

NASA Astrophysics Data System (ADS)

McMullin, D. R.; Seely, J. F.; Bremer, J.; Jones, A. R.; Vest, R.; Sakdinawat, A.

2015-12-01

Free-standing zone plates for use in EUV solar radiometers have been fabricated using electron beam lithography and calibrated at the NIST SURF synchrotron facility. The radiometers that we are developing use zone plates (ZPs) to focus the total solar irradiance in narrow EUV spectral bands and measure it with negligible sensitivity to field angle and polarization, and with greater accuracy and greater long-term stability than radiometers that have alternative architectures. These radiometers are easy to accommodate on spacecraft due to their small size, low mass, low power requirements, low data rates, and modest pointing requirements. A proto-type instrument will be presented with performance characteristics and spacecraft resource requirements for hosting these new instruments. The compact size of the optical train make these zone plates attractive for small CubeSats. The robustness of the compact design makes these radiometers available for a large variety of applications.

Pitfalls in setting up genetic studies on preeclampsia.

PubMed

Laivuori, Hannele

2013-04-01

This presentation will consider approaches to discover susceptibility genes for a complex genetic disorder such as preeclampsia. The clinical disease presumably results from the additive effects of multiple sequence variants from the mother and the foetus together with environmental factors. Disease heterogeneity and underpowered study designs are likely to be behind non-reproducible results in candidate gene association studies. To avoid spurious findings, sample size and characteristics of the study populations as well as replication studies in an independent study population should be an essential part of a study design. In family-based linkage studies relationship with genotype and phenotype may be modified by a variety of factors. The large number of families needed in discovering genetic variants with modest effect sizes is difficult to attain. Moreover, the identification of underlying mutations has proven difficult. When pooling data or performing meta-analyses from different populations, disease and locus heterogeneity may become a major issue. First genome-wide association studies (GWAS) have identified risk loci for preeclampsia. Adequately powered replication studies are critical in order to replicate the initial GWAS findings. This approach requires rigorous multiple testing correction. The expected effect sizes of individual sequence variants on preeclampsia are small, but this approach is likely to decipher new clues to the pathogenesis. The rare variants, gene-gene and gene-environmental interactions as well as noncoding genetic variations and epigenetics are expected to explain the missing heritability. Next-generation sequencing technologies will make large amount of data on genomes and transcriptomes available. Complexity of the data poses a challenge. Different depths of coverage might be chosen depending on the design of the study, and validation of the results by different methods is mandatory. In order to minimize disease heterogeneity in genetic studies of preeclampsia, identification of subtypes and intermediate phenotypes would be highly desirable. Copyright © 2013. Published by Elsevier B.V.

An employee total health management-based survey of Iowa employers.

PubMed

Merchant, James A; Lind, David P; Kelly, Kevin M; Hall, Jennifer L

2013-12-01

To implement an Employee Total Health Management (ETHM) model-based questionnaire and provide estimates of model program elements among a statewide sample of Iowa employers. Survey a stratified random sample of Iowa employers, and characterize and estimate employer participation in ETHM program elements. Iowa employers are implementing less than 30% of all 12 components of ETHM, with the exception of occupational safety and health (46.6%) and workers' compensation insurance coverage (89.2%), but intend modest expansion of all components in the coming year. The ETHM questionnaire-based survey provides estimates of progress Iowa employers are making toward implementing components of Total Worker Health programs.

Nanofibrillated cellulose causes acute pulmonary inflammation that subsides within a month.

PubMed

Ilves, Marit; Vilske, Sara; Aimonen, Kukka; Lindberg, Hanna K; Pesonen, Saila; Wedin, Irene; Nuopponen, Markus; Vanhala, Esa; Højgaard, Casper; Winther, Jakob R; Willemoës, Martin; Vogel, Ulla; Wolff, Henrik; Norppa, Hannu; Savolainen, Kai; Alenius, Harri

2018-05-30

Nanofibrillated cellulose (NFC) is a renewable nanomaterial that has beneficial uses in various applications such as packaging materials and paper. Like carbon nanotubes (CNT), NFCs have high aspect ratio and favorable mechanical properties. The aspect ratio also rises a concern whether NFC could pose a health risk and induce pathologies, similar to those triggered by multi-walled CNT. In this study, we explored the immunomodulatory properties of four NFCs in vitro and in vivo, and compared the results with data on bulk-sized cellulose fibrils and rigid multi-walled CNT (rCNT). Two of the NFCs were non-functionalized and two were carboxymethylated or carboxylated. We investigated the production of pro-inflammatory cytokines in differentiated THP-1 cells, and studied the pulmonary effects and biopersistence of the materials in mice. Our results demonstrate that one of the non-functionalized NFCs tested reduced cell viability and triggered pro-inflammatory reactions in vitro. In contrast, all cellulose materials induced innate immunity response in vivo 24 h after oropharyngeal aspiration, and the non-functionalized NFCs additionally caused features of Th2-type inflammation. Modest immune reactions were also seen after 28 days, however, the effects were markedly attenuated as compared with the ones after 24 h. Cellulose materials were not cleared within 1 month, as demonstrated by their presence in the exposed lungs. All effects of NFC were modest as compared with those induced by rCNT. NFC-induced responses were similar or exceeded those triggered by bulk-sized cellulose. These data provide new information about the biodurability and pulmonary effects of different NFCs; this knowledge can be useful in the risk assessment of cellulose materials.

Nonspecific DNA Binding and Bending by HUαβ: Interfaces of the Three Binding Modes Characterized by Salt Dependent Thermodynamics

PubMed Central

Koh, Junseock; Shkel, Irina; Saecker, Ruth M.; Record, M. Thomas

2011-01-01

Previous ITC and FRET studies demonstrated that Escherichia coli HUαβ binds nonspecifically to duplex DNA in three different binding modes: a tighter-binding 34 bp mode which interacts with DNA in large (>34 bp) gaps between bound proteins, reversibly bending it 140° and thereby increasing its flexibility, and two weaker, modestly cooperative small-site-size modes (10 bp, 6 bp) useful for filling gaps between bound proteins shorter than 34 bp. Here we use ITC to determine the thermodynamics of these binding modes as a function of salt concentration, and deduce that DNA in the 34 bp mode is bent around but not wrapped on the body of HU, in contrast to specific binding of IHF. Analyses of binding isotherms (8, 15, 34 bp DNA) and initial binding heats (34, 38, 160 bp DNA) reveal that all three modes have similar log-log salt concentration derivatives of the binding constants (Ski) even though their binding site sizes differ greatly; most probable values of Ski on 34 bp or larger DNA are − 7.5 ± 0.5. From the similarity of Ski values, we conclude that binding interfaces of all three modes involve the same region of the arms and saddle of HU. All modes are entropy-driven, as expected for nonspecific binding driven by the polyelectrolyte effect. The bent-DNA 34 bp mode is most endothermic, presumably because of the cost of HU-induced DNA bending, while the 6 bp mode is modestly exothermic at all salt concentrations examined. Structural models consistent with the observed Ski values are proposed. PMID:21513716

Observations of Titan IIIC Transtage Fragmentation Debris

NASA Technical Reports Server (NTRS)

Cowardin, Heather; Seitzer, P.; Abercromby, K.; Barker, E.; Buckalew, B.; Cardona, T.; Krisko, P.; Lederer, S.

2013-01-01

The fragmentation of a Titan IIIC Transtage (1968-081) on 21 February 1992 is one of only two known break-ups in or near geosynchronous orbit. The original rocket body and 24 pieces of debris are currently being tracked by the U. S. Space Surveillance Network (SSN). The rocket body (SSN# 3432) and several of the original fragments (SSN# 25000, 25001, 30000, and 33511) were observed in survey mode during 2004-2010 using the 0.6-m Michigan Orbital DEbris Survey Telescope (MODEST) in Chile using a broad R filter. This paper presents a size distribution for all calibrated magnitude data acquired on MODEST. Size distribution plots are also shown using historical models for small fragmentation debris (down to 10 cm) thought to be associated with the Titan Transtage break-up. In November 2010, visible broadband photometry (Johnson/Kron-Cousins BVRI) was acquired with the 0.9-m Small and Moderate Aperture Research Telescope System (SMARTS) at the Cerro Tololo Inter-American Observatory (CTIO) in Chile on several Titan fragments (SSN 25001, 33509, and 33510) and the parent rocket body (SSN 3432). Color index data are used to determine the fragment brightness distribution and how the data compares to spacecraft materials measured in the laboratory using similar photometric measurement techniques. In order to better characterize the break-up fragments, spectral measurements were acquired on three Titan fragments (one fragment observed over two different time periods) using the 6.5-m Magellan telescopes at Las Campanas Observatory in Chile. The telescopic spectra of SSN 25000 (May 2012 and January 2013), SSN 38690, and SSN 38699 are compared with laboratory acquired spectra of materials (e.g., aluminum and various paints) to determine the surface material.

Small Aerostationary Telecommunications Orbiter Concept for Mars in the 2020s

NASA Technical Reports Server (NTRS)

Lock, Robert E.; Edwards, Charles D., Jr.; Nicholas, Austin; Woolley, Ryan; Bell, David J.

2016-01-01

Current Mars science orbiters carry UHF proximity payloads to provide limited access and data services to landers and rovers on Mars surface. In the era of human spaceflight to Mars, very high rate and reliable relay services will be needed to serve a large number of supporting vehicles, habitats, and orbiters, as well as astronaut EVAs. These will likely be provided by a robust network of orbiting assets in very high orbits, such as areostationary orbits. In the decade leading to that era, telecommunications orbits can be operated at areostationary orbit that can support a significant population of robotic precursor missions and build the network capabilities needed for the human spaceflight era. Telecommunications orbiters of modest size and cost, delivered by Solar Electric Propulsion to areostationary orbit, can provide continuous access at very high data rates to users on the surface and in Mars orbit.In the era of human spaceflight to Mars very high rate andreliable relay services will be needed to serve a largenumber of supporting vehicles, habitats, and orbiters, aswell as astronaut EVAs. These could be provided by arobust network of orbiting assets in very high orbits. In thedecade leading to that era, telecommunications orbiterscould be operated at areostationary orbit that could support asignificant population of robotic precursor missions andbuild the network capabilities needed for the humanspaceflight era. These orbiters could demonstrate thecapabilities and services needed for the future but withoutthe high bandwidth and high reliability requirements neededfor human spaceflight.Telecommunications orbiters of modest size and cost,delivered by Solar Electric Propulsion to areostationaryorbit, could provide continuous access at very high datarates to users on the surface and in Mars orbit. Twoexamples highlighting the wide variety of orbiter deliveryand configuration options were shown that could providehigh-performance service to users.

Observations of Titan IIIC Transtage Fragmentation Debris

NASA Astrophysics Data System (ADS)

Cowardin, H.; Buckalew, B.; Barker, E.; Abercromby, K.; Seitzer, P.; Cardona, T.; Krisko, P.; Lederer, S.

2013-09-01

The fragmentation of a Titan IIIC Transtage (1968-081) on 21 February 1992 is one of only two known break-ups in or near geosynchronous orbit. The original rocket body and 24 pieces of debris are currently being tracked by the U. S. Space Surveillance Network (SSN). The rocket body (SSN# 3432) and several of the original fragments (SSN# 25000, 25001, 30000, and 33511) were observed in survey mode during 2004-2010 using the 0.6 m Michigan Orbital DEbris Survey Telescope (MODEST) in Chile using a broad R filter. This paper presents a size distribution for all calibrated magnitude data acquired on MODEST. Size distribution plots are also shown using historical models for small fragmentation debris (down to 10 cm) thought to be associated with the Titan Transtage break-up. In November 2010, visible broadband photometry (Johnson/Kron-Cousins BVRI) was acquired with the 0.9 m Small and Moderate Aperture Research Telescope System (SMARTS) at the Cerro Tololo Inter-American Observatory (CTIO) in Chile on several Titan fragments (SSN 25001, 33509, and 33510) and the parent rocket body (SSN 3432). Color index data are used to determine the fragment brightness distribution and how the data compares to spacecraft materials measured in the laboratory using similar photometric measurement techniques. In order to better characterize the break-up fragments, spectral measurements were acquired on three Titan fragments (one fragment observed over two different time periods) using the 6.5-m Magellan telescopes at Las Campanas Observatory in Chile. The telescopic spectra of SSN 25000 (May 2012 and January 2013), SSN 38690, and SSN 38699 are compared with laboratory acquired spectra of materials (e.g., aluminum and various paints) to determine the surface material.

Restless Legs Syndrome and Depression: Effect Mediation by Disturbed Sleep and Periodic Limb Movements.

PubMed

Koo, Brian B; Blackwell, Terri; Lee, Hochang B; Stone, Katie L; Louis, Elan D; Redline, Susan

2016-11-01

To investigate an association between restless legs syndrome (RLS) and depression and to what extent sleep disturbance, periodic limb movements during sleep (PLMS), and antidepressant medication mediate this relationship. A cross-sectional analysis was conducted of the Osteoporotic Fractures in Older Men Study data in 982 men assessed for RLS (International RLS Study Group scale [IRLSS]) and depression (Geriatric Depression Scale [GDS]), who underwent actigraphy (for sleep latency/efficiency) and polysomnography (for PLMS). Men were split into three groups: no RLS (N = 815), mild RLS (IRLSS ≤ 12, N = 85), moderate-to-severe RLS (IRLSS > 12, N = 82). Depression was defined as GDS score ≥ 6. Logistic and linear regression assessed associations of RLS and depression or number depressive symptoms, respectively. Models were adjusted for age, site, race, education, body mass index, personal habits, benzodiazepine/dopaminergic medication, physical activity, cardiovascular risk factors, and apnea-hypopnea index. Of 982 men, 167 (17.0%) had RLS. Depression was significantly associated with moderate-to-severe RLS after adjustment (versus no RLS: OR [95% CI] 2.85 [1.23, 6.64]). Further adjustment for potential mediators attenuated effect size modestly, most for sleep efficiency (OR: 2.85-2.55). Compared with no RLS, moderate-to-severe RLS was associated with the number of depressive symptoms after adjustment (adjusted means [95% CI]; no RLS: 1.14 [1.05, 1.24] versus IRLSS > 12: 1.69 [1.32, 2.11]). Further adjustment for potential mediators did not alter effect size. For men with PLMS index at least median, number of depressive symptoms significantly increased as RLS category became more severe. Depression is more common as RLS severity worsens. The RLS-depression relationship is modestly explained by sleep disturbance and PLMS. Published by Elsevier Inc.

The role of self-construal in predicting self-presentational motives for online social network use in the UK and Japan.

PubMed

Long, Karen; Zhang, Xiao

2014-07-01

Self-presentational motives underlying online social network (OSN) use were explored in samples of British and Japanese users. Self-expression, maintaining privacy, and attention seeking were strong motives in both samples; impression management and modesty were less strongly endorsed. Measures of independent and interdependent self-construal, as well as narcissism and modesty, were investigated as potential predictors of these motivations. Independent self-construal emerged as the most important predictor across both samples, with less independent participants showing more concern with image management and modesty. Participants with more interdependent self-construals were more concerned about maintaining privacy. There were some differences in the patterns of prediction between the samples, but overall self-construal measures contributed to the explanation of the majority of the motivations, whereas narcissistic or modest personality variables did not.

Limited genetic covariance between autistic traits and intelligence: findings from a longitudinal twin study.

PubMed

Hoekstra, Rosa A; Happé, Francesca; Baron-Cohen, Simon; Ronald, Angelica

2010-07-01

Intellectual disability is common in individuals with autism spectrum conditions. However, the strength of the association between both conditions and its relevance to finding the underlying (genetic) causes of autism is unclear. This study aimed to investigate the longitudinal association between autistic traits and intelligence in a general population twin sample and to examine the etiology of this association. Parental ratings of autistic traits and performance on intelligence tests were collected in a sample of 8,848 twin pairs when the children were 7/8, 9, and 12 years old. Phenotypic and longitudinal correlations in the sample as a whole were compared to the associations in the most extreme scoring 5% of the population. The genetic and environmental influences on the overlap between autistic traits and IQ and on the stability of this relationship over time were estimated using structural equation modeling. Autistic traits were modestly negatively correlated to intellectual ability, both in the extreme scoring groups and among the full-range scores. The correlation was stable over time and was mainly explained by autistic trait items assessing communication difficulties. Genetic model fitting showed that autistic traits and IQ were influenced by a common set of genes and a common set of environmental influences that continuously affect these traits throughout childhood. The genetic correlation between autistic traits and IQ was only modest. These findings suggest that individual differences in autistic traits are substantially genetically independent of intellectual functioning. The relevance of these findings to future studies is discussed. (c) 2010 Wiley-Liss, Inc.

Drinking, Cigarette Smoking, and Employment Among American College Freshmen at a Four-Year University.

PubMed

Bono, Rose S; Barnes, Andrew J; Dick, Danielle M; Kendler, Kenneth S

2017-01-28

For American college students, alcohol and cigarette use are important health concerns, and employment concurrent with school attendance is on the rise. Given the lifelong importance of employment and substance use trajectories begun in college, parsing out the relationship between the two is meaningful. This study's purpose is to determine whether employment during college is associated with substance use. Cross-sectional associations between employment (work hours, earnings) and substance use (drinking frequency, drinking quantity, smoking frequency) were estimated using partial proportional odds models in a sample of N = 1457 freshmen attending a large, public 4-year university in 2011, after accounting for demographics, personality, social environment, and parental influences. Working 10 more hours and earning $50 more per week as a freshman had modest positive associations with higher smoking frequency and with moderate drinking frequency and quantity prior to adjustment. After adjustment, work hours remained modestly associated with moderate drinking frequency and quantity. No adjusted associations were found among employment measures and smoking or between weekly earnings and drinking frequency. Different relationships emerged for moderate versus heavy alcohol use frequency and quantity. Both employment and substance use are commonplace among college freshmen. After extensive controls for potential confounders, the relationship between the two appears modest. Employment may yet play a role in college student substance use, but work hours and earnings are likely only small parts of a larger web of influences on drinking and smoking.

Drinking, Cigarette Smoking, and Employment among American College Freshmen at a Four-Year University

PubMed Central

Bono, Rose S.; Barnes, Andrew J.; Dick, Danielle M.; Kendler, Kenneth S.

2017-01-01

Background For American college students, alcohol and cigarette use are important health concerns, and employment concurrent with school attendance is on the rise. Given the lifelong importance of employment and substance use trajectories begun in college, parsing out the relationship between the two is meaningful. Objectives This study’s purpose is to determine whether employment during college is associated with substance use. Methods Cross-sectional associations between employment (work hours, earnings) and substance use (drinking frequency, drinking quantity, smoking frequency) were estimated using partial proportional odds models in a sample of N=1457 freshmen attending a large, public 4-year university in 2011, after accounting for demographics, personality, social environment, and parental influences. Results Working 10 more hours and earning $50 more per week as a freshman had modest positive associations with higher smoking frequency and with moderate drinking frequency and quantity prior to adjustment. After adjustment, work hours remained modestly associated with moderate drinking frequency and quantity. No adjusted associations were found among employment measures and smoking or between weekly earnings and drinking frequency. Different relationships emerged for moderate versus heavy alcohol use frequency and quantity. Conclusions Both employment and substance use are commonplace among college freshmen. After extensive controls for potential confounders, the relationship between the two appears modest. Employment may yet play a role in college student substance use, but work hours and earnings are likely only small parts of a larger web of influences on drinking and smoking. PMID:27754728

Optimal flexible sample size design with robust power.

PubMed

Zhang, Lanju; Cui, Lu; Yang, Bo

2016-08-30

It is well recognized that sample size determination is challenging because of the uncertainty on the treatment effect size. Several remedies are available in the literature. Group sequential designs start with a sample size based on a conservative (smaller) effect size and allow early stop at interim looks. Sample size re-estimation designs start with a sample size based on an optimistic (larger) effect size and allow sample size increase if the observed effect size is smaller than planned. Different opinions favoring one type over the other exist. We propose an optimal approach using an appropriate optimality criterion to select the best design among all the candidate designs. Our results show that (1) for the same type of designs, for example, group sequential designs, there is room for significant improvement through our optimization approach; (2) optimal promising zone designs appear to have no advantages over optimal group sequential designs; and (3) optimal designs with sample size re-estimation deliver the best adaptive performance. We conclude that to deal with the challenge of sample size determination due to effect size uncertainty, an optimal approach can help to select the best design that provides most robust power across the effect size range of interest. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Influence of wet distiller's grains on prevalence of Escherichia coli O157:H7 and Salmonella in feedlot cattle and antimicrobial susceptibility of generic Escherichia coli isolates.

PubMed

Edrington, Tom S; MacDonald, Jim C; Farrow, Russell L; Callaway, Todd R; Anderson, Robin C; Nisbet, David J

2010-05-01

The current research examined the inclusion of 20% wet distiller's grains (WDG) fed with steam-flaked corn (SFC) or dry-rolled corn (DRC) in diets fed to feedlot cattle on fecal prevalence of Escherichia coli O157:H7 and Salmonella. Crossbred beef heifers (n = 272; average initial body weight (BW) = 354 kg) were blocked by BW and pen size and randomly assigned to treatment. Fecal samples from freshly voided fecal pats were collected from each pen on the day cattle shipped for slaughter (237 fecal samples: 72, 125, and 40 from cattle 132, 160, and 181 days on feed, respectively). Fecal samples were cultured quantitatively and qualitatively for the above pathogens. Populations of E. coli O157:H7 and Salmonella were generally low with very few samples containing quantifiable populations. Similarly, after enrichment, few samples were E. coli O157:H7 positive in any collection with no treatment differences (p > 0.10). More samples were Salmonella positive during the first collection with an increased (p < 0.05) prevalence observed in the SFC and DRC treatments compared with DRC + WDG treatment. No other treatment differences were observed for Salmonella. Putative fecal coliform isolates (18 per treatment; first collection) were examined for antimicrobial susceptibility, and the majority were susceptible to all of the antibiotics examined. Most of the resistance was observed in the SFC (n = 3) and DRC (n = 4) treatments, and only one isolate in each of the two WDG treatments demonstrated resistance (one antibiotic each, streptomycin and tetracycline). All multidrug resistance (2-4 antibiotics) was observed in isolates cultured from the DRC and SFC treatments (n = 2 isolates in each treatment). Results of the current research found no significant effect of feeding WDG to feedlot cattle on fecal prevalence, at time of shipment for slaughter, of E. coli O157:H7, and only modest differences (decreases) in Salmonella prevalence with no apparent affect on antimicrobial susceptibility of fecal coliform isolates.

Characterizing Microbial Community and Geochemical Dynamics at Hydrothermal Vents Using Osmotically Driven Continuous Fluid Samplers

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

Robidart, Julie C.; Callister, Stephen J.; Song, Peng F.

2013-05-07

Microbes play a key role in mediating all aquatic biogeochemical cycles, and ongoing efforts are aimed at better understanding the relationships between microbial phylogenetic and physiological diversity, and habitat physical and chemical characteristics. Establishing such relationships is facilitated by sampling and studying microbiology and geochemistry at the appropriate spatial and temporal scales, to access information on the past and current environmental state that contributes to observed microbial abundances and activities. A modest number of sampling systems exist to date, few of which can be used in remote, harsh environments such as hydrothermal vents, where the ephemeral nature of venting underscoresmore » the necessity for higher resolution sampling. We have developed a robust, continuous fluid sampling system for co-registered microbial and biogeochemical analyses. The osmosis-powered bio-osmosampling system (BOSS) use no electricity, collects fluids with daily resolution or better, can be deployed in harsh, inaccessible environments and can sample fluids continuously for up to five years. Here we present a series of tests to examine DNA, RNA and protein stability over time, as well as material compatability, via lab experiments. We also conducted two field deployments at deep-sea hydrothermal vents to assess changes in microbial diversity and protein expression as a function of the physico-chemical environment. Our data reveal significant changes in microbial community composition co-occurring with relatively modest changes in the geochemistry. These data additionally provide new insights into the distribution of an enigmatic sulfur oxidizing symbiont in its free-living state. Data from the second deployment reveal differences in the representation of peptides over time, underscoring the utility of the BOSS in meta-proteomic studies. In concert, these data demonstrate the efficacy of this approach, and illustrate the value of using this method to study microbial and geochemical phenomena.« less

[Effect sizes, statistical power and sample sizes in "the Japanese Journal of Psychology"].

PubMed

Suzukawa, Yumi; Toyoda, Hideki

2012-04-01

This study analyzed the statistical power of research studies published in the "Japanese Journal of Psychology" in 2008 and 2009. Sample effect sizes and sample statistical powers were calculated for each statistical test and analyzed with respect to the analytical methods and the fields of the studies. The results show that in the fields like perception, cognition or learning, the effect sizes were relatively large, although the sample sizes were small. At the same time, because of the small sample sizes, some meaningful effects could not be detected. In the other fields, because of the large sample sizes, meaningless effects could be detected. This implies that researchers who could not get large enough effect sizes would use larger samples to obtain significant results.

Siblings of children with a chronic illness: a meta-analysis.

PubMed

Sharpe, Donald; Rossiter, Lucille

2002-12-01

To review the literature pertaining to the siblings of children with a chronic illness. Fifty-one published studies and 103 effect sizes were identified and examined through meta-analysis. We found (1) a modest, negative effect size statistic existed for siblings of children with a chronic illness relative to comparison participants or normative data; (2) heterogeneity existed for those effect sizes; (3) parent reports were more negative than child self-reports; (4) psychological functioning (i.e., depression, anxiety), peer activities, and cognitive development scores were lower for siblings of children with a chronic illness compared to controls; and (5) a cluster of chronic illnesses with daily treatment regimes was associated with negative effect statistics compared to chronic illnesses that did not affect daily functioning. More methodologically sound studies investigating the psychological functioning of siblings of children with a chronic illness are needed. Clinicians need to know that siblings of children with a chronic illness are at risk for negative psychological effects. Intervention programs for the siblings and families of children with a chronic illness should be developed.

Sample Size Estimation: The Easy Way

ERIC Educational Resources Information Center

Weller, Susan C.

2015-01-01

This article presents a simple approach to making quick sample size estimates for basic hypothesis tests. Although there are many sources available for estimating sample sizes, methods are not often integrated across statistical tests, levels of measurement of variables, or effect sizes. A few parameters are required to estimate sample sizes and…

A multivariate analysis of genetic constraints to life history evolution in a wild population of red deer.

PubMed

Walling, Craig A; Morrissey, Michael B; Foerster, Katharina; Clutton-Brock, Tim H; Pemberton, Josephine M; Kruuk, Loeske E B

2014-12-01

Evolutionary theory predicts that genetic constraints should be widespread, but empirical support for their existence is surprisingly rare. Commonly applied univariate and bivariate approaches to detecting genetic constraints can underestimate their prevalence, with important aspects potentially tractable only within a multivariate framework. However, multivariate genetic analyses of data from natural populations are challenging because of modest sample sizes, incomplete pedigrees, and missing data. Here we present results from a study of a comprehensive set of life history traits (juvenile survival, age at first breeding, annual fecundity, and longevity) for both males and females in a wild, pedigreed, population of red deer (Cervus elaphus). We use factor analytic modeling of the genetic variance-covariance matrix ( G: ) to reduce the dimensionality of the problem and take a multivariate approach to estimating genetic constraints. We consider a range of metrics designed to assess the effect of G: on the deflection of a predicted response to selection away from the direction of fastest adaptation and on the evolvability of the traits. We found limited support for genetic constraint through genetic covariances between traits, both within sex and between sexes. We discuss these results with respect to other recent findings and to the problems of estimating these parameters for natural populations. Copyright © 2014 Walling et al.

A Multivariate Analysis of Genetic Constraints to Life History Evolution in a Wild Population of Red Deer

PubMed Central

Walling, Craig A.; Morrissey, Michael B.; Foerster, Katharina; Clutton-Brock, Tim H.; Pemberton, Josephine M.; Kruuk, Loeske E. B.

2014-01-01

Evolutionary theory predicts that genetic constraints should be widespread, but empirical support for their existence is surprisingly rare. Commonly applied univariate and bivariate approaches to detecting genetic constraints can underestimate their prevalence, with important aspects potentially tractable only within a multivariate framework. However, multivariate genetic analyses of data from natural populations are challenging because of modest sample sizes, incomplete pedigrees, and missing data. Here we present results from a study of a comprehensive set of life history traits (juvenile survival, age at first breeding, annual fecundity, and longevity) for both males and females in a wild, pedigreed, population of red deer (Cervus elaphus). We use factor analytic modeling of the genetic variance–covariance matrix (G) to reduce the dimensionality of the problem and take a multivariate approach to estimating genetic constraints. We consider a range of metrics designed to assess the effect of G on the deflection of a predicted response to selection away from the direction of fastest adaptation and on the evolvability of the traits. We found limited support for genetic constraint through genetic covariances between traits, both within sex and between sexes. We discuss these results with respect to other recent findings and to the problems of estimating these parameters for natural populations. PMID:25278555

Subcutaneous Infiltration of Carbon Dioxide (Carboxytherapy) for Abdominal Fat Reduction: A Randomized Clinical Trial.

PubMed

Alam, Murad; Sadhwani, Divya; Geisler, Amelia; Aslam, Imran; Makin, Inder Raj S; Schlessinger, Daniel I; Disphanurat, Wareeporn; Pongprutthipan, Marisa; Voravutinon, Nataya; Weil, Alexandra; Chen, Brian R; West, Dennis P; Veledar, Emir; Poon, Emily

2018-04-23

Non-invasive fat removal is preferred because of decreased downtime and lower perceived risk. It is important to seek new non-invasive fat removal treatments that are both safe and efficacious. To assess the extent to which carboxytherapy, the insufflation of carbon dioxide gas into subcutaneous fat, results in reduction of fat volume. Randomized, sham-controlled, split-body study. Adults (BMI 22-29) were randomized to receive five weekly infusions of 1000 cc CO 2 to one side of the abdomen, and five sham treatments to the contralateral side. Primary outcome measures were ultrasound measurement of fat layer thickness, as well as total circumference before and after treatment. Sixteen participants completed the study. Ultrasound measurement indicated less fat volume on the sides treated with carboxytherapy one week after the last treatment, (p=0.011), but was not maintained at 28 weeks. Total circumference decreased nominally but not significantly at Week 5 compared to baseline (p=0.0697). Participant body weights did not change over the entire course of the study (p=1.00) LIMITATIONS: Limitations included modest sample size and some sources of error in circumference and fat layer measurements. Carboxytherapy provides a transient decrease in subcutaneous fat that may not persist. Treatment is well-tolerated. Copyright © 2018. Published by Elsevier Inc.

[Genetic dissection of intracranial aneurysm].

PubMed

Onda, Hideaki; Yoneyama, Taku; Akagawa, Hiroyuki; Kasuya, Hidetoshi

2008-11-01

Subarachnoid hemorrhage (SAH) due to rupture of an intracranial aneurysm (IA) is a devastating condition with high mortality and morbidity. Genetic as well as environment factors play important roles in the pathogenesis of SAH and IAs. We review the present knowledge on the genetic factors responsible for SAH or IAs. Linkage analysis and association study are used for genetic dissection. Genome-wide linkage analyses have specified several genetic loci for IAs and 6 loci (1p34-36, 7q11, 11q24-25, 14q22-31, 19q13, and Xp22) have been replicated in different populations. Numerous functional and/or positional candidate genes for IAs have been investigated by case-control association studies. The results of genetic association studies are modest because of small sample sizes. To date, no specific genes have been identified as responsible for IA development or rupture. Recent, large-scale genome-wide association (GWA) studies have revealed consistent and replicable genetic markers of several complex diseases such as coronary artery disease and type 2 diabetes. Although, thus far, no GWA studies have been performed for IAs, such a study may accomplish the breakthrough of genetic dissection of IAs. The identification of susceptible genes might lead to the understanding of the mechanism of IA formation or rupture and to novel therapeutic strategies.

Diminished Stream Nitrate Concentrations Linked to Dissolved Organic Carbon Dynamics After Leaf Fall

NASA Astrophysics Data System (ADS)

Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Doctor, D. H.; Kendall, C.

2004-05-01

Thermodynamic coupling of the nitrogen and carbon cycles has broad implications for controls on catchment nutrient fluxes. In the northeast US, leaf fall occurs in early October and the availability of organic carbon increases as the leaves decompose. At the Sleepers River Research Watershed in northeastern Vermont (USA), we sampled stream chemistry from seven nested catchments to determine how stream dissolved organic carbon (DOC) and nitrate vary as a function of flow conditions, land-use, and basin size in response to leaf fall. Following leaf fall, nitrate concentration patterns were quantitatively different from other times of the year. Under baseflow conditions, stream and soil water DOC concentrations were higher than normal, whereas nitrate concentrations declined sharply at the five smallest catchments and more modestly at the two largest catchments. Under high flow conditions, flushing of nitrate was observed, as is typical for stormflow response at Sleepers River. Our field data suggest that in-stream processing of nitrate is likely thermodynamically and kinetically favorable under baseflow but not at higher flow conditions when expanding variable source areas make hydrological connections between nitrate source areas and streams. We are working to evaluate this hypothesis with isotopic and other monitoring data, and to model the coupled interactions of water, DOC, and nitrate fluxes in these nested catchments.

Patterns of cortisol and alpha-amylase reactivity to psychosocial stress in maltreated women

PubMed Central

Mielock, Alyssa S.; Morris, Matthew C.; Rao, Uma

2016-01-01

Background Childhood maltreatment can trigger enduring changes in major stress response systems, particularly in the context of major depressive disorder (MDD). However, the relative impact of maltreatment versus MDD on hypothalamic-pituitary-adrenal axis and sympathetic-adrenal-medullary system stress reactivity is not well understood. Method This study examined salivary cortisol and alpha-amylase responses to the Trier Social Stress Test (TSST) in 26 maltreated (15 with current MDD) and 26 non-maltreated (17 with current MDD) women. Results Maltreated women showed greater anticipatory cortisol reactivity during the TSST protocol compared to non-maltreated women. Maltreated women also showed rapid deceleration in cortisol levels. Whereas non-maltreated women showed initial declines in alpha-amylase levels but rapidly increasing alpha-amylase levels during the TSST protocol, maltreated women did not exhibit changes in alpha-amylase levels during the TSST protocol. Contrary to expectation, MDD did not impact cortisol or alpha-amylase responses. Limitations The present study is limited by retrospective report of childhood maltreatment, cross-sectional design, and modest sample sizes. Conclusions These findings suggest that childhood maltreatment plays a greater role driving alterations in cortisol and alpha-amylase stress reactivity than MDD. Understanding the biological embedding of maltreatment is critical for elucidating mechanisms linking these experiences to risk for negative mental and physical health outcomes. PMID:27875756

Cool-Water Carbonates, SEPM Special Publication No. 56

NASA Astrophysics Data System (ADS)

Hallock, Pamela

Doesn't field work on modern carbonates mean scuba diving on spectacular coral reefs in gin-clear water teeming with brightly colored fish? Not if you are one of the researchers that Jonathan Clarke of the Western Mining Corporation Ltd., in Preston, Victoria, Australia, assembled at a workshop in Geelong, Victoria, in January 1995. Their field work involves research cruises in high-latitude oceans, where mal de mer and chilling winds are constant companions. Many braved 10-m seas in modest-sized research vessels to sample shelves stripped of fine sediments by storm waves whose effects can reach to depths exceeding 200 m. Noel James of Queen's University in Kingston, Ontario, carefully lays the groundwork for the book in a paper titled, “The Cool-Water Carbonate Depositional Realm,” which will assuredly become a standard reading assignment in advanced undergraduate-and graduate-level courses in carbonate sedimentology. James skillfully shows how cool-water carbonates are part of the greater carbonate depositional spectrum. By expanding recognition of the possible range of carbonate environments, sedimentologists expand their ability to understand and interpret ancient carbonates, particularly Paleozoic limestones that often show striking similarities to modern cool-water sediments. James' paper is followed by nine papers on modern cool-water carbonates, seven on Tertiary environments, and seven examples from Mesozoic and Paleozoic limestones

To tell or not to tell? Psychopathic traits and response integrity in youth delinquency surveys.

PubMed

Laajasalo, Taina; Aronen, Eeva T; Saukkonen, Suvi; Salmi, Venla; Aaltonen, Mikko; Kivivuori, Janne

2016-04-01

Individuals with high psychopathy scores are capable of providing valid self-reports on their own personality traits, but there have been no empirical studies of the effect of psychopathic features on responding to sensitive survey questions about specific behaviours. The aim of this study is to investigate any relationship between facets of psychopathy and participants' willingness to report antisocial acts in youth delinquency surveys, controlling for demographic variables known to be associated with response integrity. In a nationally representative sample of 4,855 Finnish mainstream adolescents aged 15-16, honesty of responding was assessed through direct response integrity questions related to violence, property crime and drug use. Psychopathy was measured with the Antisocial Process Screening Device - Self Report (APSD-SR). Callous-unemotional traits and, to a lesser degree, narcissistic features were associated with a dishonest response style, although the effect size was modest. Although psychopathy does not seem to influence the capability and willingness to report personality traits accurately, it may be associated with endorsing dishonest responses to questions about specific behaviours that have possible repercussions. Our findings suggest that previously observed associations between adolescents' self-reported delinquent behaviour and psychopathic traits may be underestimations of the strength of the effects. Copyright © 2014 John Wiley & Sons, Ltd.

Decision-making and cognitive abilities: A review of associations between Iowa Gambling Task performance, executive functions, and intelligence.

PubMed

Toplak, Maggie E; Sorge, Geoff B; Benoit, André; West, Richard F; Stanovich, Keith E

2010-07-01

The Iowa Gambling Task (IGT) has been used to study decision-making differences in many different clinical and developmental samples. It has been suggested that IGT performance captures abilities that are separable from cognitive abilities, including executive functions and intelligence. The purpose of the current review was to examine studies that have explicitly examined the relationship between IGT performance and these cognitive abilities. We included 43 studies that reported correlational analyses with IGT performance, including measures of inhibition, working memory, and set-shifting as indices of executive functions, as well as measures of verbal, nonverbal, and full-scale IQ as indices of intelligence. Overall, only a small proportion of the studies reported a statistically significant relationship between IGT performance and these cognitive abilities. The majority of studies reported a non-significant relationship. Of the minority of studies that reported statistically significant effects, effect sizes were, at best, small to modest, and confidence intervals were large, indicating that considerable variability in performance on the IGT is not captured by current measures of executive function and intelligence. These findings highlight the separability between decision-making on the IGT and cognitive abilities, which is consistent with recent conceptualizations that differentiate rationality from intelligence. 2010 Elsevier Ltd. All rights reserved.

Genetics of preeclampsia: what are the challenges?

PubMed

Bernard, Nathalie; Giguère, Yves

2003-07-01

Despite recent efforts to identify susceptibility genes of preeclampsia, the genetic determinants of the condition remain ill-defined, as is the situation for most disorders of complex inheritance patterns. The angiotensinogen, factor V, and methylenetetrahydrofolate reductase genes have been investigated in different populations, as have other genes involved in blood pressure, vascular volume control, thrombophilia, lipid metabolism, oxidative stress, and endothelial dysfunction. The study of the genetics of complex traits is faced with both methodological and genetic issues; these include adequate sample size to allow for the identification of modest genetic effects, of gene-gene and gene-environment interactions, the study of adequate quantitative traits and extreme phenotypes, haplotype analyses, statistical genetics, genome-wide (hypothesis-free) versus candidate-gene (hypothesis-driven) approaches, and the validation of positive associations. The use of genetically well-characterized populations showing a founder effect, such as the French-Canadian population of Quebec, in genetic association studies, may help to unravel the susceptibility genes of disorders showing complex inheritance, such as preeclampsia. It is necessary to better evaluate the role of the fetal genome in the resulting predisposition to preeclampsia and its complications. Eventually, we may be able to integrate genetic information to better identify the women at risk of developing preeclampsia, and to improve the management of those suffering from this condition.

Cognitive dysfunction in Body Dysmorphic Disorder: New implications for nosological systems & neurobiological models

PubMed Central

Jefferies-Sewell, K; Chamberlain, SR; Fineberg, NA; Laws, KR

2017-01-01

Background Body dysmorphic disorder (BDD) is a debilitating disorder, characterised by obsessions and compulsions relating specifically to perceived appearance, newly classified within the DSM-5 Obsessive-Compulsive and Related Disorders grouping. Until now, little research has been conducted into the cognitive profile of this disorder. Materials and Methods Participants with BDD (n=12) and healthy controls (n=16) were tested using a computerised neurocognitive battery investigating attentional set-shifting (Intra/Extra Dimensional Set Shift Task), decision-making (Cambridge Gamble Task), motor response-inhibition (Stop-Signal Reaction Time Task) and affective processing (Affective Go-No Go Task). The groups were matched for age, IQ and education. Results In comparison to controls, patients with BDD showed significantly impaired attentional set shifting, abnormal decision-making, impaired response inhibition and greater omission and commission errors on the emotional processing task. Conclusions Despite the modest sample size, our results showed that individuals with BDD performed poorly compared to healthy controls on tests of cognitive flexibility, reward and motor impulsivity and affective processing. Results from separate studies in OCD patients suggest similar cognitive dysfunction. Therefore, these findings are consistent with the re-classification of BDD alongside OCD. These data also hint at additional areas of decision-making abnormalities that might contribute specifically to the psychopathology of BDD. PMID:27899165

Complementary Public Service Announcements as a Strategy for Enhancing the Impact of Health-Promoting Messages in Fictional Television Programs.

PubMed

Bavin, Lynda M; Owens, R Glynn

2018-05-01

Research suggests that health-promoting storylines in developed nations' fictional television programs can have a beneficial impact on viewers' beliefs, attitudes, intentions, or behaviors. The sizes of the effects are generally modest; however, the audience reach is substantial. Given that many fictional programs may hold the prolonged attention of millions of viewers, it is of value to examine potential strategies for enhancing the persuasive impact of their health-promoting storylines. Complementary public service announcements may be a promising strategy. This randomized experimental study (N = 310) examined the effects of viewing a complementary public service announcement after an organ donation story in an episode of Grey's Anatomy. Results indicated that the public service announcement enhanced the beneficial impact of the story on viewers' discussion behavior (about one's organ donor wishes), discussion intention, and perceived learning. This experimental study is the first to examine the effects of viewing a non-character public service announcement after a health-related storyline in a developed nation's fictional program compared to viewing the same episode of the program on its own. It is important for future research to examine whether these findings replicate for different health issues and with a nationally representative sample.

Atherosclerosis risk factors in American Indians with Alzheimer disease: preliminary findings.

PubMed

Weiner, Myron F; Rosenberg, Roger N; Womack, Kyle B; Svetlik, Doris A; Fuller, Carey; Fields, Julie; Hynan, Linda S

2008-01-01

Factors predisposing to and associated with atherosclerosis may impact the onset and progression of Alzheimer disease (AD). The high prevalence of atherosclerosis and associated risk factors in American Indians makes them ideal subjects to test this association. We compared frequency of history of hypertension, myocardial infarction, stroke, diabetes, and high cholesterol in 34 American Indians with AD with 34 age-matched American Indian controls, and 34 age-matched whites with probable AD. We also measured waist size, height, and weight, and acquired blood for determination of plasma homocysteine and apolipoprotein E genotype. The 3 groups did not differ significantly in age or sex. History of hypertension and diabetes was significantly more common among American Indian AD patients than Indian controls or whites with AD. The 3 groups did not differ in history of stroke or myocardial infarction. Body mass index was significantly greater in both Indian groups than the white AD group. Plasma homocysteine levels were greater, but not significantly so, in the Indian AD than the Indian control group. Thus, there is preliminary evidence of a modest association between history of hypertension and diabetes and AD in a small sample of American Indians. This suggests that changes in lifestyle factors could influence the expression of AD in American Indians.

Physical Activity Outcomes of Nurse-Delivered Lifestyle Interventions.

PubMed

Richards, Elizabeth A; Cai, Yun

2016-02-01

Promotion of physical activity has been a public health priority for decades. Over two million home healthcare nurses are at the front line to deliver effective health education and health promotion interventions in the United States. The purpose of this systematic review is to examine the effectiveness of nurse-delivered lifestyle physical interventions on physical activity outcomes conducted in home settings. Computerized database and ancestry search strategies located distinct intervention trials between 1990 and 2015. A total of eight quantitative studies were reviewed. Four of the eight studies were randomized control trials and four studies used an uncontrolled pretest-posttest design. The eight studies represented a total of 1,221 participants with mean ages from 43 to 81. Study sample sizes ranged from 16 to 504. Seven of the eight studies demonstrated modest effect of nurse-delivered home-based interventions on physical activity behaviors. Home-based physical activity promotion was most often incorporated into secondary prevention of postacute diseases, chronic disease management, or disease prevention/health promotion. Findings indicate that nurse-delivered home-based physical activity promotion show overall effectiveness in general adult populations. Possible effective intervention domains were also discussed in this review to guide future home-based health promotion. More large randomized controlled trials with longer study/follow-up periods and studies with cost-effectiveness data are warranted in future research.

Brain volumetric changes and cognitive ageing during the eighth decade of life

PubMed Central

Dickie, David Alexander; Cox, Simon R.; Valdes Hernandez, Maria del C.; Corley, Janie; Royle, Natalie A.; Pattie, Alison; Aribisala, Benjamin S.; Redmond, Paul; Muñoz Maniega, Susana; Taylor, Adele M.; Sibbett, Ruth; Gow, Alan J.; Starr, John M.; Bastin, Mark E.; Wardlaw, Joanna M.; Deary, Ian J.

2015-01-01

Abstract Later‐life changes in brain tissue volumes—decreases in the volume of healthy grey and white matter and increases in the volume of white matter hyperintensities (WMH)—are strong candidates to explain some of the variation in ageing‐related cognitive decline. We assessed fluid intelligence, memory, processing speed, and brain volumes (from structural MRI) at mean age 73 years, and at mean age 76 in a narrow‐age sample of older individuals (n = 657 with brain volumetric data at the initial wave, n = 465 at follow‐up). We used latent variable modeling to extract error‐free cognitive levels and slopes. Initial levels of cognitive ability were predictive of subsequent brain tissue volume changes. Initial brain volumes were not predictive of subsequent cognitive changes. Brain volume changes, especially increases in WMH, were associated with declines in each of the cognitive abilities. All statistically significant results were modest in size (absolute r‐values ranged from 0.114 to 0.334). These results build a comprehensive picture of macrostructural brain volume changes and declines in important cognitive faculties during the eighth decade of life. Hum Brain Mapp 36:4910–4925, 2015. © 2015 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc PMID:26769551

High Spatial Resolution Europa Coverage by the Galileo Near Infrared Mapping Spectrometer (NIMS)

NASA Technical Reports Server (NTRS)

1997-01-01

The NIMS instrument on the Galileo spacecraft, which is being used to map the mineral and ice properties over the surfaces of the Jovian moons, produces global spectral images at modest spatial resolution and high resolution spectral images for small selected regions on the satellites. This map illustrates the high resolution coverage of Europa obtained by NIMS through the April 1997 G7 orbit.

The areas covered are displayed on a Voyager-derived map. A good sampling of the dark trailing-side material (180 to 360 degrees) has been obtained, with less coverage of Europa's leading side.

The false-color composites use red, green and blue to represent the infrared brightnesses at 0.7, 1.51 and 1.82 microns respectively. Considerable variations are evident and are related to the composition and sizes of the surface grains.

The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov.

Environmental drivers of variability in the movement ecology of turkey vultures (Cathartes aura) in North and South America.

PubMed

Dodge, Somayeh; Bohrer, Gil; Bildstein, Keith; Davidson, Sarah C; Weinzierl, Rolf; Bechard, Marc J; Barber, David; Kays, Roland; Brandes, David; Han, Jiawei; Wikelski, Martin

2014-01-01

Variation is key to the adaptability of species and their ability to survive changes to the Earth's climate and habitats. Plasticity in movement strategies allows a species to better track spatial dynamics of habitat quality. We describe the mechanisms that shape the movement of a long-distance migrant bird (turkey vulture, Cathartes aura) across two continents using satellite tracking coupled with remote-sensing science. Using nearly 10 years of data from 24 satellite-tracked vultures in four distinct populations, we describe an enormous amount of variation in their movement patterns. We related vulture movement to environmental conditions and found important correlations explaining how far they need to move to find food (indexed by the Normalized Difference Vegetation Index) and how fast they can move based on the prevalence of thermals and temperature. We conclude that the extensive variability in the movement ecology of turkey vultures, facilitated by their energetically efficient thermal soaring, suggests that this species is likely to do well across periods of modest climate change. The large scale and sample sizes needed for such analysis in a widespread migrant emphasizes the need for integrated and collaborative efforts to obtain tracking data and for policies, tools and open datasets to encourage such collaborations and data sharing.

Does the extended Glasgow Outcome Scale add value to the conventional Glasgow Outcome Scale?

PubMed

Weir, James; Steyerberg, Ewout W; Butcher, Isabella; Lu, Juan; Lingsma, Hester F; McHugh, Gillian S; Roozenbeek, Bob; Maas, Andrew I R; Murray, Gordon D

2012-01-01

The Glasgow Outcome Scale (GOS) is firmly established as the primary outcome measure for use in Phase III trials of interventions in traumatic brain injury (TBI). However, the GOS has been criticized for its lack of sensitivity to detect small but clinically relevant changes in outcome. The Glasgow Outcome Scale-Extended (GOSE) potentially addresses this criticism, and in this study we estimate the efficiency gain associated with using the GOSE in place of the GOS in ordinal analysis of 6-month outcome. The study uses both simulation and the reanalysis of existing data from two completed TBI studies, one an observational cohort study and the other a randomized controlled trial. As expected, the results show that using an ordinal technique to analyze the GOS gives a substantial gain in efficiency relative to the conventional analysis, which collapses the GOS onto a binary scale (favorable versus unfavorable outcome). We also found that using the GOSE gave a modest but consistent increase in efficiency relative to the GOS in both studies, corresponding to a reduction in the required sample size of the order of 3-5%. We recommend that the GOSE be used in place of the GOS as the primary outcome measure in trials of TBI, with an appropriate ordinal approach being taken to the statistical analysis.

Optical Photometric Observations of GEO Debris

NASA Technical Reports Server (NTRS)

Seitzer, Patrick; Rodriquez-Cowardin, Heather M.; Barker, Edwin S.; Abercromby, Kira J.; Kelecy, Thomas M.; Horstman, Matt

2010-01-01

We report on a continuing program of optical photometric measurements of faint orbital debris at geosynchronous Earth orbit (GEO). These observations can be compared with laboratory studies of actual spacecraft materials in an effort to determine what the faint debris at GEO may be. We have optical observations from Cerro Tololo Inter-American Observatory (CTIO) in Chile of two samples of debris: 1. GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Curtis-Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the CTIO/SMARTS 0.9-m for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R = 15 t11 magnitude that are discovered in the MODEST survey. 2. A smaller sample of high area to mass ratio (AMR) objects discovered independently, and acquired using predictions from orbits derived from independent tracking data collected days prior to the observations. Our optical observations in standard astronomical BVRI filters are done with either telescope, and with the telescope tracking the debris object at the object's angular rate. Observations in different filters are obtained sequentially. We have obtained 71 calibrated sequences of R-B-V-I-R magnitudes. A total of 66 of these sequences have 3 or more good measurements in all filters (not contaminated by star streaks or in Earth's shadow). Most of these sequences show brightness variations, but a small subset has observed brightness variations consistent with that expected from observational errors alone. The majority of these stable objects are redder than a solar color in both B-R and R-I. There is no dependence on color with brightness. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus, the B-R color is a true measure of the surface of the debris piece facing the telescopes for that observation. Any change in color reflects a real change in the debris surface. We will compare our observations with models and laboratory measurements of selected surfaces.

Asthma and genes encoding components of the vitamin D pathway

PubMed Central

2009-01-01

Background Genetic variants at the vitamin D receptor (VDR) locus are associated with asthma and atopy. We hypothesized that polymorphisms in other genes of the vitamin D pathway are associated with asthma or atopy. Methods Eleven candidate genes were chosen for this study, five of which code for proteins in the vitamin D metabolism pathway (CYP27A1, CYP27B1, CYP2R1, CYP24A1, GC) and six that are known to be transcriptionally regulated by vitamin D (IL10, IL1RL1, CD28, CD86, IL8, SKIIP). For each gene, we selected a maximally informative set of common SNPs (tagSNPs) using the European-derived (CEU) HapMap dataset. A total of 87 SNPs were genotyped in a French-Canadian family sample ascertained through asthmatic probands (388 nuclear families, 1064 individuals) and evaluated using the Family Based Association Test (FBAT) program. We then sought to replicate the positive findings in four independent samples: two from Western Canada, one from Australia and one from the USA (CAMP). Results A number of SNPs in the IL10, CYP24A1, CYP2R1, IL1RL1 and CD86 genes were modestly associated with asthma and atopy (p < 0.05). Two-gene models testing for both main effects and the interaction were then performed using conditional logistic regression. Two-gene models implicating functional variants in the IL10 and VDR genes as well as in the IL10 and IL1RL1 genes were associated with asthma (p < 0.0002). In the replicate samples, SNPs in the IL10 and CYP24A1 genes were again modestly associated with asthma and atopy (p < 0.05). However, the SNPs or the orientation of the risk alleles were different between populations. A two-gene model involving IL10 and VDR was replicated in CAMP, but not in the other populations. Conclusion A number of genes involved in the vitamin D pathway demonstrate modest levels of association with asthma and atopy. Multilocus models testing genes in the same pathway are potentially more effective to evaluate the risk of asthma, but the effects are not uniform across populations. PMID:19852851

The Relationship between Sample Sizes and Effect Sizes in Systematic Reviews in Education

ERIC Educational Resources Information Center

Slavin, Robert; Smith, Dewi

2009-01-01

Research in fields other than education has found that studies with small sample sizes tend to have larger effect sizes than those with large samples. This article examines the relationship between sample size and effect size in education. It analyzes data from 185 studies of elementary and secondary mathematics programs that met the standards of…

Phylogenetic effective sample size.

PubMed

Bartoszek, Krzysztof

2016-10-21

In this paper I address the question-how large is a phylogenetic sample? I propose a definition of a phylogenetic effective sample size for Brownian motion and Ornstein-Uhlenbeck processes-the regression effective sample size. I discuss how mutual information can be used to define an effective sample size in the non-normal process case and compare these two definitions to an already present concept of effective sample size (the mean effective sample size). Through a simulation study I find that the AICc is robust if one corrects for the number of species or effective number of species. Lastly I discuss how the concept of the phylogenetic effective sample size can be useful for biodiversity quantification, identification of interesting clades and deciding on the importance of phylogenetic correlations. Copyright © 2016 Elsevier Ltd. All rights reserved.

The endothelial sample size analysis in corneal specular microscopy clinical examinations.

PubMed

Abib, Fernando C; Holzchuh, Ricardo; Schaefer, Artur; Schaefer, Tania; Godois, Ronialci

2012-05-01

To evaluate endothelial cell sample size and statistical error in corneal specular microscopy (CSM) examinations. One hundred twenty examinations were conducted with 4 types of corneal specular microscopes: 30 with each BioOptics, CSO, Konan, and Topcon corneal specular microscopes. All endothelial image data were analyzed by respective instrument software and also by the Cells Analyzer software with a method developed in our lab. A reliability degree (RD) of 95% and a relative error (RE) of 0.05 were used as cut-off values to analyze images of the counted endothelial cells called samples. The sample size mean was the number of cells evaluated on the images obtained with each device. Only examinations with RE < 0.05 were considered statistically correct and suitable for comparisons with future examinations. The Cells Analyzer software was used to calculate the RE and customized sample size for all examinations. Bio-Optics: sample size, 97 ± 22 cells; RE, 6.52 ± 0.86; only 10% of the examinations had sufficient endothelial cell quantity (RE < 0.05); customized sample size, 162 ± 34 cells. CSO: sample size, 110 ± 20 cells; RE, 5.98 ± 0.98; only 16.6% of the examinations had sufficient endothelial cell quantity (RE < 0.05); customized sample size, 157 ± 45 cells. Konan: sample size, 80 ± 27 cells; RE, 10.6 ± 3.67; none of the examinations had sufficient endothelial cell quantity (RE > 0.05); customized sample size, 336 ± 131 cells. Topcon: sample size, 87 ± 17 cells; RE, 10.1 ± 2.52; none of the examinations had sufficient endothelial cell quantity (RE > 0.05); customized sample size, 382 ± 159 cells. A very high number of CSM examinations had sample errors based on Cells Analyzer software. The endothelial sample size (examinations) needs to include more cells to be reliable and reproducible. The Cells Analyzer tutorial routine will be useful for CSM examination reliability and reproducibility.

Accounting for twin births in sample size calculations for randomised trials.

PubMed

Yelland, Lisa N; Sullivan, Thomas R; Collins, Carmel T; Price, David J; McPhee, Andrew J; Lee, Katherine J

2018-05-04

Including twins in randomised trials leads to non-independence or clustering in the data. Clustering has important implications for sample size calculations, yet few trials take this into account. Estimates of the intracluster correlation coefficient (ICC), or the correlation between outcomes of twins, are needed to assist with sample size planning. Our aims were to provide ICC estimates for infant outcomes, describe the information that must be specified in order to account for clustering due to twins in sample size calculations, and develop a simple tool for performing sample size calculations for trials including twins. ICCs were estimated for infant outcomes collected in four randomised trials that included twins. The information required to account for clustering due to twins in sample size calculations is described. A tool that calculates the sample size based on this information was developed in Microsoft Excel and in R as a Shiny web app. ICC estimates ranged between -0.12, indicating a weak negative relationship, and 0.98, indicating a strong positive relationship between outcomes of twins. Example calculations illustrate how the ICC estimates and sample size calculator can be used to determine the target sample size for trials including twins. Clustering among outcomes measured on twins should be taken into account in sample size calculations to obtain the desired power. Our ICC estimates and sample size calculator will be useful for designing future trials that include twins. Publication of additional ICCs is needed to further assist with sample size planning for future trials. © 2018 John Wiley & Sons Ltd.

Sample size determination for mediation analysis of longitudinal data.

PubMed

Pan, Haitao; Liu, Suyu; Miao, Danmin; Yuan, Ying

2018-03-27

Sample size planning for longitudinal data is crucial when designing mediation studies because sufficient statistical power is not only required in grant applications and peer-reviewed publications, but is essential to reliable research results. However, sample size determination is not straightforward for mediation analysis of longitudinal design. To facilitate planning the sample size for longitudinal mediation studies with a multilevel mediation model, this article provides the sample size required to achieve 80% power by simulations under various sizes of the mediation effect, within-subject correlations and numbers of repeated measures. The sample size calculation is based on three commonly used mediation tests: Sobel's method, distribution of product method and the bootstrap method. Among the three methods of testing the mediation effects, Sobel's method required the largest sample size to achieve 80% power. Bootstrapping and the distribution of the product method performed similarly and were more powerful than Sobel's method, as reflected by the relatively smaller sample sizes. For all three methods, the sample size required to achieve 80% power depended on the value of the ICC (i.e., within-subject correlation). A larger value of ICC typically required a larger sample size to achieve 80% power. Simulation results also illustrated the advantage of the longitudinal study design. The sample size tables for most encountered scenarios in practice have also been published for convenient use. Extensive simulations study showed that the distribution of the product method and bootstrapping method have superior performance to the Sobel's method, but the product method was recommended to use in practice in terms of less computation time load compared to the bootstrapping method. A R package has been developed for the product method of sample size determination in mediation longitudinal study design.

A genome-wide association study identifies multiple loci associated with mathematics ability and disability

PubMed Central

Docherty, S J; Davis, O S P; Kovas, Y; Meaburn, E L; Dale, P S; Petrill, S A; Schalkwyk, L C; Plomin, R

2010-01-01

Numeracy is as important as literacy and exhibits a similar frequency of disability. Although its etiology is relatively poorly understood, quantitative genetic research has demonstrated mathematical ability to be moderately heritable. In this first genome-wide association study (GWAS) of mathematical ability and disability, 10 out of 43 single nucleotide polymorphism (SNP) associations nominated from two high- vs. low-ability (n = 600 10-year-olds each) scans of pooled DNA were validated (P < 0.05) in an individually genotyped sample of *2356 individuals spanning the entire distribution of mathematical ability, as assessed by teacher reports and online tests. Although the effects are of the modest sizes now expected for complex traits and require further replication, interesting candidate genes are implicated such as NRCAM which encodes a neuronal cell adhesion molecule. When combined into a set, the 10 SNPs account for 2.9% (F = 56.85; df = 1 and 1881; P = 7.277e–14) of the phenotypic variance. The association is linear across the distribution consistent with a quantitative trait locus (QTL) hypothesis; the third of children in our sample who harbour 10 or more of the 20 risk alleles identified are nearly twice as likely (OR = 1.96; df = 1; P = 3.696e–07) to be in the lowest performing 15% of the distribution. Our results correspond with those of quantitative genetic research in indicating that mathematical ability and disability are influenced by many genes generating small effects across the entire spectrum of ability, implying that more highly powered studies will be needed to detect and replicate these QTL associations. PMID:20039944

Increased sensitivity to positive social stimuli in monozygotic twins at risk of bipolar vs. unipolar disorder.

PubMed

Kærsgaard, S; Meluken, I; Kessing, L V; Vinberg, M; Miskowiak, K W

2018-05-01

Abnormalities in affective cognition are putative endophenotypes for bipolar and unipolar disorders but it is unclear whether some abnormalities are disorder-specific. We therefore investigated affective cognition in monozygotic twins at familial risk of bipolar disorder relative to those at risk of unipolar disorder and to low-risk twins. Seventy monozygotic twins with a co-twin history of bipolar disorder (n = 11), of unipolar disorder (n = 38) or without co-twin history of affective disorder (n = 21) were included. Variables of interest were recognition of and vigilance to emotional faces, emotional reactivity and -regulation in social scenarios and non-affective cognition. Twins at familial risk of bipolar disorder showed increased recognition of low to moderate intensity of happy facial expressions relative to both unipolar disorder high-risk twins and low-risk twins. Bipolar disorder high-risk twins also displayed supraliminal attentional avoidance of happy faces compared with unipolar disorder high-risk twins and greater emotional reactivity in positive and neutral social scenarios and less reactivity in negative social scenarios than low-risk twins. In contrast with our hypothesis, there was no negative bias in unipolar disorder high-risk twins. There were no differences between the groups in demographic characteristics or non-affective cognition. The modest sample size limited the statistical power of the study. Increased sensitivity and reactivity to positive social stimuli may be a neurocognitive endophenotype that is specific for bipolar disorder. If replicated in larger samples, this 'positive endophenotype' could potentially aid future diagnostic differentiation between unipolar and bipolar disorder. Copyright © 2018 Elsevier B.V. All rights reserved.

Measuring Preferences for a Diabetes Pay-for-Performance for Patient (P4P4P) Program using a Discrete Choice Experiment.

PubMed

Chen, Tsung-Tai; Tung, Tao-Hsin; Hsueh, Ya-Seng Arthur; Tsai, Ming-Han; Liang, Hsiu-Mei; Li, Kay-Lun; Chung, Kuo-Piao; Tang, Chao-Hsiun

2015-07-01

To elicit a patient's willingness to participate in a diabetes pay-for-performance for patient (P4P4P) program using a discrete choice experiment method. The survey was conducted in March 2013. Our sample was drawn from patients with diabetes at five hospitals in Taiwan (International Classification of Diseases, Ninth Revision, Clinical Modification code 250). The sample size was 838 patients. The discrete choice experiment questionnaire included the attributes monthly cash rewards, exercise time, diet control, and program duration. We estimated a bivariate probit model to derive willingness-to-accept levels after accounting for the characteristics (e.g., severity and comorbidity) of patients with diabetes. The preferred program was a 3-year program involving 30 minutes of exercise per day and flexible diet control. Offering an incentive of approximately US $67 in cash per month appears to increase the likelihood that patients with diabetes will participate in the preferred P4P4P program by approximately 50%. Patients with more disadvantageous characteristics (e.g., elderly, low income, greater comorbidity, and severity) could have less to gain from participating in the program and thus require a higher monetary incentive to compensate for the disutility caused by participating in the program's activities. Our result demonstrates that a modest financial incentive could increase the likelihood of program participation after accounting for the attributes of the P4P4P program and patients' characteristics. Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Negative appraisals and fear extinction are independently related to PTSD symptoms.

PubMed

Zuj, Daniel V; Palmer, Matthew A; Gray, Kate E; Hsu, Chia-Ming K; Nicholson, Emma L; Malhi, Gin S; Bryant, Richard A; Felmingham, Kim L

2017-08-01

Considerable research has revealed impaired fear extinction to be a significant predictor of PTSD. Fear extinction is also considered the primary mechanism of exposure therapy, and a critical factor in PTSD recovery. The cognitive theory of PTSD proposes that symptoms persist due to excessive negative appraisals about the trauma and its sequelae. Research has not yet examined the relationship between fear extinction and negative appraisals in PTSD. A cross-sectional sample of participants with PTSD (n =21), and trauma-exposed controls (n =33) underwent a standardized differential fear conditioning and extinction paradigm, with skin conductance response (SCR) amplitude serving as the index of conditioned responses. The Posttraumatic Cognitions Inventory (PTCI) was used to index catastrophic negative appraisals. Participants with PTSD demonstrated a slower decrease in overall SCR responses during extinction and greater negative appraisals compared to the group. A moderation analysis revealed that both negative trauma-relevant appraisals and fear extinction learning were independently associated with PTSD symptoms, but there was no moderation interaction. The current study was limited by a modest sample size, leading to the inclusion of participants with subclinical PTSD symptoms. Further, the current study only assessed fear extinction learning; including a second day extinction recall task may show alternative effects. These findings indicate that negative appraisals and fear extinction did not interact, but had independent relationships with PTSD symptoms. Here we show for the first time in an experimental framework that negative appraisals and fear extinction play separate roles in PTSD symptoms. Copyright © 2017 Elsevier B.V. All rights reserved.

Temporal and vertical variability in optical properties of New England shelf waters during late summer and spring

NASA Astrophysics Data System (ADS)

Sosik, Heidi M.; Green, Rebecca E.; Pegau, W. Scott; Roesler, Collin S.

2001-05-01

Relationships between optical and physical properties were examined on the basis of intensive sampling at a site on the New England continental shelf during late summer 1996 and spring 1997. During both seasons, particles were found to be the primary source of temporal and vertical variability in optical properties since light absorption by dissolved material, though significant in magnitude, was relatively constant. Within the particle pool, changes in phytoplankton were responsible for much of the observed optical variability. Physical processes associated with characteristic seasonal patterns in stratification and mixing contributed to optical variability mostly through effects on phytoplankton. An exception to this generalization occurred during summer as the passage of a hurricane led to a breakdown in stratification and substantial resuspension of nonphytoplankton particulate material. Prior to the hurricane, conditions in summer were highly stratified with subsurface maxima in absorption and scattering coefficients. In spring, stratification was much weaker but increased over the sampling period, and a modest phytoplankton bloom caused surface layer maxima in absorption and scattering coefficients. These seasonal differences in the vertical distribution of inherent optical properties were evident in surface reflectance spectra, which were elevated and shifted toward blue wavelengths in the summer. Some seasonal differences in optical properties, including reflectance spectra, suggest that a significant shift toward a smaller particle size distribution occurred in summer. Shorter timescale optical variability was consistent with a variety of influences including episodic events such as the hurricane, physical processes associated with shelfbreak frontal dynamics, biological processes such as phytoplankton growth, and horizontal patchiness combined with water mass advection.

Mobile phone use and location of glioma: a case-case analysis.

PubMed

Hartikka, Hanna; Heinävaara, Sirpa; Mäntylä, Riitta; Kähärä, Veikko; Kurttio, Päivi; Auvinen, Anssi

2009-04-01

We assessed a new approach for evaluating the glioma risk among users of mobile phones to focus on the part of the brain most heavily exposed to radiofrequency electromagnetic fields from mobile phones. The tumor midpoint was defined from radiological imaging. A case-case analysis with 99 gliomas was performed using logistic regression. The exposed cases were those with the tumor mid-point within 4.6 cm from the line between the mouth and the external meatus of the ear, representing the most likely location of the mobile phone (the source of exposure). Alternative analyses based on various indicators of mobile phone use as the outcome were also carried out. The majority of cases were regular mobile phone users. A slightly higher proportion of gliomas among mobile phone users than non-users occurred within 4.6 cm from the presumed location of the mobile phone (28% vs. 14%). Modestly elevated odds ratios were observed for several indicators of mobile phone use, but without an exposure gradient. The highest odds ratios were found for contralateral and short-term use. Our results, though limited by the small sample size, demonstrate that detailed information on tumor location allows evaluation of the risk related to the most heavily exposed part of the brain, representing direct evaluation of the possible local carcinogenic effects of the radiofrequency fields. However, field strength varies between users and over time also within a given anatomic site, due to the output power of the phone. Collaborative analysis of a larger sample is planned. (c) 2009 Wiley-Liss, Inc.

A genome-wide association study identifies multiple loci associated with mathematics ability and disability.

PubMed

Docherty, S J; Davis, O S P; Kovas, Y; Meaburn, E L; Dale, P S; Petrill, S A; Schalkwyk, L C; Plomin, R

2010-03-01

Numeracy is as important as literacy and exhibits a similar frequency of disability. Although its etiology is relatively poorly understood, quantitative genetic research has demonstrated mathematical ability to be moderately heritable. In this first genome-wide association study (GWAS) of mathematical ability and disability, 10 out of 43 single nucleotide polymorphism (SNP) associations nominated from two high- vs. low-ability (n = 600 10-year-olds each) scans of pooled DNA were validated (P < 0.05) in an individually genotyped sample of (*)2356 individuals spanning the entire distribution of mathematical ability, as assessed by teacher reports and online tests. Although the effects are of the modest sizes now expected for complex traits and require further replication, interesting candidate genes are implicated such as NRCAM which encodes a neuronal cell adhesion molecule. When combined into a set, the 10 SNPs account for 2.9% (F = 56.85; df = 1 and 1881; P = 7.277e-14) of the phenotypic variance. The association is linear across the distribution consistent with a quantitative trait locus (QTL) hypothesis; the third of children in our sample who harbour 10 or more of the 20 risk alleles identified are nearly twice as likely (OR = 1.96; df = 1; P = 3.696e-07) to be in the lowest performing 15% of the distribution. Our results correspond with those of quantitative genetic research in indicating that mathematical ability and disability are influenced by many genes generating small effects across the entire spectrum of ability, implying that more highly powered studies will be needed to detect and replicate these QTL associations.

Maternal childhood trauma, postpartum depression, and infant outcomes: Avoidant affective processing as a potential mechanism.

PubMed

Choi, Karmel W; Sikkema, Kathleen J; Vythilingum, Bavi; Geerts, Lut; Faure, Sheila C; Watt, Melissa H; Roos, Annerine; Stein, Dan J

2017-03-15

Women who have experienced childhood trauma may be at risk for postpartum depression, increasing the likelihood of negative outcomes among their children. Predictive pathways from maternal childhood trauma to child outcomes, as mediated by postpartum depression, require investigation. A longitudinal sample of South African women (N=150) was followed through pregnancy and postpartum. Measures included maternal trauma history reported during pregnancy; postpartum depression through six months; and maternal-infant bonding, infant development, and infant physical growth at one year. Structural equation models tested postpartum depression as a mediator between maternal experiences of childhood trauma and children's outcomes. A subset of women (N=33) also participated in a lab-based emotional Stroop paradigm, and their responses to fearful stimuli at six weeks were explored as a potential mechanism linking maternal childhood trauma, postpartum depression, and child outcomes. Women with childhood trauma experienced greater depressive symptoms through six months postpartum, which then predicted negative child outcomes at one year. Mediating effects of postpartum depression were significant, and persisted for maternal-infant bonding and infant growth after controlling for covariates and antenatal distress. Maternal avoidance of fearful stimuli emerged as a potential affective mechanism. Limitations included modest sample size, self-report measures, and unmeasured potential confounders. Findings suggest a mediating role of postpartum depression in the intergenerational transmission of negative outcomes. Perinatal interventions that address maternal trauma histories and depression, as well as underlying affective mechanisms, may help interrupt cycles of disadvantage, particularly in high-trauma settings such as South Africa. Copyright © 2017. Published by Elsevier B.V.

Public Opinion Polls, Chicken Soup and Sample Size

ERIC Educational Resources Information Center

Nguyen, Phung

2005-01-01

Cooking and tasting chicken soup in three different pots of very different size serves to demonstrate that it is the absolute sample size that matters the most in determining the accuracy of the findings of the poll, not the relative sample size, i.e. the size of the sample in relation to its population.

Sample size in studies on diagnostic accuracy in ophthalmology: a literature survey.

PubMed

Bochmann, Frank; Johnson, Zoe; Azuara-Blanco, Augusto

2007-07-01

To assess the sample sizes used in studies on diagnostic accuracy in ophthalmology. Design and sources: A survey literature published in 2005. The frequency of reporting calculations of sample sizes and the samples' sizes were extracted from the published literature. A manual search of five leading clinical journals in ophthalmology with the highest impact (Investigative Ophthalmology and Visual Science, Ophthalmology, Archives of Ophthalmology, American Journal of Ophthalmology and British Journal of Ophthalmology) was conducted by two independent investigators. A total of 1698 articles were identified, of which 40 studies were on diagnostic accuracy. One study reported that sample size was calculated before initiating the study. Another study reported consideration of sample size without calculation. The mean (SD) sample size of all diagnostic studies was 172.6 (218.9). The median prevalence of the target condition was 50.5%. Only a few studies consider sample size in their methods. Inadequate sample sizes in diagnostic accuracy studies may result in misleading estimates of test accuracy. An improvement over the current standards on the design and reporting of diagnostic studies is warranted.

Comparing the Bioburden Measured by Adenosine Triphosphate (ATP) Luminescence Technology to Contact Plate-Based Microbiologic Sampling to Assess the Cleanliness of the Patient Care Environment.

PubMed

Salsgiver, Elizabeth; Bernstein, Daniel; Simon, Matthew S; Greendyke, William; Jia, Haomiao; Robertson, Amy; Salter, Selma; Schuetz, Audrey N; Saiman, Lisa; Furuya, E Yoko; Calfee, David P

2018-05-01

The correlation between ATP concentration and bacterial burden in the patient care environment was assessed. These findings suggest that a correlation exists between ATP concentration and bacterial burden, and they generally support ATP technology manufacturer-recommended cutoff values. Despite relatively modest discriminative ability, this technology may serve as a useful proxy for cleanliness.Infect Control Hosp Epidemiol 2018;39:622-624.

Caution regarding the choice of standard deviations to guide sample size calculations in clinical trials.

PubMed

Chen, Henian; Zhang, Nanhua; Lu, Xiaosun; Chen, Sophie

2013-08-01

The method used to determine choice of standard deviation (SD) is inadequately reported in clinical trials. Underestimations of the population SD may result in underpowered clinical trials. This study demonstrates how using the wrong method to determine population SD can lead to inaccurate sample sizes and underpowered studies, and offers recommendations to maximize the likelihood of achieving adequate statistical power. We review the practice of reporting sample size and its effect on the power of trials published in major journals. Simulated clinical trials were used to compare the effects of different methods of determining SD on power and sample size calculations. Prior to 1996, sample size calculations were reported in just 1%-42% of clinical trials. This proportion increased from 38% to 54% after the initial Consolidated Standards of Reporting Trials (CONSORT) was published in 1996, and from 64% to 95% after the revised CONSORT was published in 2001. Nevertheless, underpowered clinical trials are still common. Our simulated data showed that all minimal and 25th-percentile SDs fell below 44 (the population SD), regardless of sample size (from 5 to 50). For sample sizes 5 and 50, the minimum sample SDs underestimated the population SD by 90.7% and 29.3%, respectively. If only one sample was available, there was less than 50% chance that the actual power equaled or exceeded the planned power of 80% for detecting a median effect size (Cohen's d = 0.5) when using the sample SD to calculate the sample size. The proportions of studies with actual power of at least 80% were about 95%, 90%, 85%, and 80% when we used the larger SD, 80% upper confidence limit (UCL) of SD, 70% UCL of SD, and 60% UCL of SD to calculate the sample size, respectively. When more than one sample was available, the weighted average SD resulted in about 50% of trials being underpowered; the proportion of trials with power of 80% increased from 90% to 100% when the 75th percentile and the maximum SD from 10 samples were used. Greater sample size is needed to achieve a higher proportion of studies having actual power of 80%. This study only addressed sample size calculation for continuous outcome variables. We recommend using the 60% UCL of SD, maximum SD, 80th-percentile SD, and 75th-percentile SD to calculate sample size when 1 or 2 samples, 3 samples, 4-5 samples, and more than 5 samples of data are available, respectively. Using the sample SD or average SD to calculate sample size should be avoided.

SSTs, nitrogen fertiliser and stratospheric ozone

NASA Technical Reports Server (NTRS)

Turco, R. P.; Whitten, R. C.; Poppoff, I. G.; Capone, L. A.

1978-01-01

A recently revised model of the stratosphere is used to show that a substantial enhancement in the ozone layer could accompany worldwide SST fleet operations and that water vapor may be an important factor in SST assessments. Revised rate coefficients for various ozone-destroying reactions are employed in calculations which indicate a slight increase in the total content of stratospheric ozone for modest-sized fleets of SSTs flying below about 25 km. It is found that water-vapor chemical reactions can negate in large part the NOx-induced ozone gains computed below 25 km and that increased use of nitrogen fertilizer might also enhance the ozone layer.

Say hello to the DSO

NASA Astrophysics Data System (ADS)

Pate, G.; Roberts, T.

1981-05-01

In the 2-to-10 GHz frequency range, the dielectrically stabilized oscillators (DSOs) with their small size, simple construction, and modest bias requirements, have advantages over cavity-stabilized oscillators (CSOs) and crystal-controlled multiplier chains (XCOs). Commercially available DSOs consist of a transistor oscillator locked to some frequency by a resonant disk of dielectric material. The disk is coupled to a microstrip line at the output of the oscillator. The stability of a DSO lies between that of a crystal-controlled oscillator and that of a cavity-stabilized oscillator. Dielectrically stabilized oscillators, built with nine basic parts and few solder joints, can be expected to be much more reliable than a CSO or XCO.

Improving the health of sex workers in NSW: maintaining success.

PubMed

Donovan, Basil; Harcourt, Christine; Egger, Sandra; Fairley, Christopher K

2010-01-01

NSW has a diverse sex industry that is limited in its size by modest demand. There is no evidence that decriminalisation in 1995 increased the frequency of commercial sex in NSW. Though the largest sector, female brothels, is now mainly staffed by Asian women, condom use for vaginal and anal sex exceeds 99% and sexually transmissible infection rates are at historic lows. These gains are attributable to the long-term support of the NSW Department of Health in collaboration with the community-based Sex Workers Outreach Project and sexual health services, facilitated by the removal of criminal sanctions without the expense and access barriers of licensing systems.

A multiscale modeling study of particle size effects on the tissue penetration efficacy of drug-delivery nanoparticles.

PubMed

Islam, Mohammad Aminul; Barua, Sutapa; Barua, Dipak

2017-11-25

Particle size is a key parameter for drug-delivery nanoparticle design. It is believed that the size of a nanoparticle may have important effects on its ability to overcome the transport barriers in biological tissues. Nonetheless, such effects remain poorly understood. Using a multiscale model, this work investigates particle size effects on the tissue distribution and penetration efficacy of drug-delivery nanoparticles. We have developed a multiscale spatiotemporal model of nanoparticle transport in biological tissues. The model implements a time-adaptive Brownian Dynamics algorithm that links microscale particle-cell interactions and adhesion dynamics to tissue-scale particle dispersion and penetration. The model accounts for the advection, diffusion, and cellular uptakes of particles. Using the model, we have analyzed how particle size affects the intra-tissue dispersion and penetration of drug delivery nanoparticles. We focused on two published experimental works that investigated particle size effects in in vitro and in vivo tissue conditions. By analyzing experimental data reported in these two studies, we show that particle size effects may appear pronounced in an in vitro cell-free tissue system, such as collagen matrix. In an in vivo tissue system, the effects of particle size could be relatively modest. We provide a detailed analysis on how particle-cell interactions may determine distribution and penetration of nanoparticles in a biological tissue. Our work suggests that the size of a nanoparticle may play a less significant role in its ability to overcome the intra-tissue transport barriers. We show that experiments involving cell-free tissue systems may yield misleading observations of particle size effects due to the absence of advective transport and particle-cell interactions.

Diagnostic accuracy research in glaucoma is still incompletely reported: An application of Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015.

PubMed

Michelessi, Manuele; Lucenteforte, Ersilia; Miele, Alba; Oddone, Francesco; Crescioli, Giada; Fameli, Valeria; Korevaar, Daniël A; Virgili, Gianni

2017-01-01

Research has shown a modest adherence of diagnostic test accuracy (DTA) studies in glaucoma to the Standards for Reporting of Diagnostic Accuracy Studies (STARD). We have applied the updated 30-item STARD 2015 checklist to a set of studies included in a Cochrane DTA systematic review of imaging tools for diagnosing manifest glaucoma. Three pairs of reviewers, including one senior reviewer who assessed all studies, independently checked the adherence of each study to STARD 2015. Adherence was analyzed on an individual-item basis. Logistic regression was used to evaluate the effect of publication year and impact factor on adherence. We included 106 DTA studies, published between 2003-2014 in journals with a median impact factor of 2.6. Overall adherence was 54.1% for 3,286 individual rating across 31 items, with a mean of 16.8 (SD: 3.1; range 8-23) items per study. Large variability in adherence to reporting standards was detected across individual STARD 2015 items, ranging from 0 to 100%. Nine items (1: identification as diagnostic accuracy study in title/abstract; 6: eligibility criteria; 10: index test (a) and reference standard (b) definition; 12: cut-off definitions for index test (a) and reference standard (b); 14: estimation of diagnostic accuracy measures; 21a: severity spectrum of diseased; 23: cross-tabulation of the index and reference standard results) were adequately reported in more than 90% of the studies. Conversely, 10 items (3: scientific and clinical background of the index test; 11: rationale for the reference standard; 13b: blinding of index test results; 17: analyses of variability; 18; sample size calculation; 19: study flow diagram; 20: baseline characteristics of participants; 28: registration number and registry; 29: availability of study protocol; 30: sources of funding) were adequately reported in less than 30% of the studies. Only four items showed a statistically significant improvement over time: missing data (16), baseline characteristics of participants (20), estimates of diagnostic accuracy (24) and sources of funding (30). Adherence to STARD 2015 among DTA studies in glaucoma research is incomplete, and only modestly increasing over time.

Interventions to reduce weight gain in schizophrenia.

PubMed

Faulkner, G; Cohn, T; Remington, G

2007-01-24

Weight gain is common for people with schizophrenia and this has serious implications for health and well being. To determine the effects of both pharmacological (excluding medication switching) and non pharmacological strategies for reducing or preventing weight gain in people with schizophrenia. We searched key databases and the Cochrane Schizophrenia Group's trials register (April 2006), reference sections within relevant papers, hand searched key journals, and contacted the first author of each relevant study and other experts to collect further information. We included all clinical randomised controlled trials comparing any pharmacological or non pharmacological intervention for weight gain (diet and exercise counselling) with standard care or other treatments for people with schizophrenia or schizophrenia-like illnesses. We reliably selected, quality assessed and extracted data from studies. As weight is a continuous outcome measurement, weighted mean differences (WMD) of the change from baseline were calculated. The primary outcome measure was weight loss. Twenty-three randomised controlled trials met the inclusion criteria for this review. Five trials assessed a cognitive/behavioural intervention and eighteen assessed a pharmacological adjunct. In terms of prevention, two cognitive/behavioural trials showed significant treatment effect (mean weight change) at end of treatment (n=104, 2 RCTs, WMD -3.38 kg CI -4.2 to -2.0). Pharmacological adjunct treatments were significant with a modest prevention of weight gain (n=274, 6 RCTs, WMD - 1.16 kg CI -1.9 to -0.4). In terms of treatments for weight loss, we found significantly greater weight reduction in the cognitive behavioural intervention group (n=129, 3 RCTs, WMD -1.69 kg CI -2.8 to -0.6) compared with standard care. Modest weight loss can be achieved with selective pharmacological and non pharmacological interventions. However, interpretation is limited by the small number of studies, small sample size, short study duration and by variability of the interventions themselves, their intensity and duration. Future studies adequately powered, with longer treatment duration and rigorous methodology will be needed in further evaluating the efficacy and safety of weight loss interventions for moderating weight gain. At this stage, there is insufficient evidence to support the general use of pharmacological interventions for weight management in people with schizophrenia.

A Brief Prenatal Intervention of Behavioral Change to Reduce the Risk of Maternal Cytomegalovirus: A Randomized Controlled Trial.

PubMed

Hughes, Brenna L; Gans, Kim M; Raker, Christina; Hipolito, Evelyn R; Rouse, Dwight J

2017-10-01

To estimate the effects of a brief prenatal behavioral intervention on risk behaviors for maternal cytomegalovirus (CMV) infection. Women were screened with CMV serology during prenatal care before 20 weeks of gestation and followed for at least 10 weeks. Women without serologic evidence of primary CMV infection were approached. Participants were apprised of serostatus and then randomized 2:1 to either a brief behavioral intervention during their prenatal care visit or to standard care (a brochure). The 7- to 10-minute in-office intervention included a video and hygiene education using motivational interviewing. Participants were then given a reminder calendar to take home and weekly text message reminders. The primary outcome was change in behavioral compliance score on a scale of 0-100. Secondary outcomes included process evaluation and domains of behavior change. A sample size of 180 participants was planned to compare the behavioral compliance score change of at least 15% between intervention and control groups with 80% power and 2.5% two-sided α. From April 2013 to October 2014, 197 women were randomized. One hundred eighty-seven (96%) had outcome data available. Mean gestational age at screening and randomization was 9 4/7 and 13 6/7 weeks of gestation, respectively. Primary outcome assessment occurred at a mean of 28 4/7 weeks of gestation. Baseline behavioral compliance scores increased modestly in the intervention group (mean: 7-point increase from 80.7 to 87.7, 95% CI 2.4-5.9) compared with the comparison group (mean: 4-point increase from 79.7 to 84.1, 95% CI 5.9-8.4; mean difference in change score: 3.0, 95% CI, 0.8-5.2; P=.007). Those in the intervention group reported change in risk perception related to perceived severity and susceptibility, self-efficacy, and perceived norms (P<.05 for all). A brief behavioral intervention delivered in the prenatal care setting was modestly effective at changing behaviors related to CMV infection risk. ClinicalTrials.gov, NCT01819519.

Dispersion and sampling of adult Dermacentor andersoni in rangeland in Western North America.

PubMed

Rochon, K; Scoles, G A; Lysyk, T J

2012-03-01

A fixed precision sampling plan was developed for off-host populations of adult Rocky Mountain wood tick, Dermacentor andersoni (Stiles) based on data collected by dragging at 13 locations in Alberta, Canada; Washington; and Oregon. In total, 222 site-date combinations were sampled. Each site-date combination was considered a sample, and each sample ranged in size from 86 to 250 10 m2 quadrats. Analysis of simulated quadrats ranging in size from 10 to 50 m2 indicated that the most precise sample unit was the 10 m2 quadrat. Samples taken when abundance < 0.04 ticks per 10 m2 were more likely to not depart significantly from statistical randomness than samples taken when abundance was greater. Data were grouped into ten abundance classes and assessed for fit to the Poisson and negative binomial distributions. The Poisson distribution fit only data in abundance classes < 0.02 ticks per 10 m2, while the negative binomial distribution fit data from all abundance classes. A negative binomial distribution with common k = 0.3742 fit data in eight of the 10 abundance classes. Both the Taylor and Iwao mean-variance relationships were fit and used to predict sample sizes for a fixed level of precision. Sample sizes predicted using the Taylor model tended to underestimate actual sample sizes, while sample sizes estimated using the Iwao model tended to overestimate actual sample sizes. Using a negative binomial with common k provided estimates of required sample sizes closest to empirically calculated sample sizes.

Simple, Defensible Sample Sizes Based on Cost Efficiency

PubMed Central

Bacchetti, Peter; McCulloch, Charles E.; Segal, Mark R.

2009-01-01

Summary The conventional approach of choosing sample size to provide 80% or greater power ignores the cost implications of different sample size choices. Costs, however, are often impossible for investigators and funders to ignore in actual practice. Here, we propose and justify a new approach for choosing sample size based on cost efficiency, the ratio of a study’s projected scientific and/or practical value to its total cost. By showing that a study’s projected value exhibits diminishing marginal returns as a function of increasing sample size for a wide variety of definitions of study value, we are able to develop two simple choices that can be defended as more cost efficient than any larger sample size. The first is to choose the sample size that minimizes the average cost per subject. The second is to choose sample size to minimize total cost divided by the square root of sample size. This latter method is theoretically more justifiable for innovative studies, but also performs reasonably well and has some justification in other cases. For example, if projected study value is assumed to be proportional to power at a specific alternative and total cost is a linear function of sample size, then this approach is guaranteed either to produce more than 90% power or to be more cost efficient than any sample size that does. These methods are easy to implement, based on reliable inputs, and well justified, so they should be regarded as acceptable alternatives to current conventional approaches. PMID:18482055

RnaSeqSampleSize: real data based sample size estimation for RNA sequencing.

PubMed

Zhao, Shilin; Li, Chung-I; Guo, Yan; Sheng, Quanhu; Shyr, Yu

2018-05-30

One of the most important and often neglected components of a successful RNA sequencing (RNA-Seq) experiment is sample size estimation. A few negative binomial model-based methods have been developed to estimate sample size based on the parameters of a single gene. However, thousands of genes are quantified and tested for differential expression simultaneously in RNA-Seq experiments. Thus, additional issues should be carefully addressed, including the false discovery rate for multiple statistic tests, widely distributed read counts and dispersions for different genes. To solve these issues, we developed a sample size and power estimation method named RnaSeqSampleSize, based on the distributions of gene average read counts and dispersions estimated from real RNA-seq data. Datasets from previous, similar experiments such as the Cancer Genome Atlas (TCGA) can be used as a point of reference. Read counts and their dispersions were estimated from the reference's distribution; using that information, we estimated and summarized the power and sample size. RnaSeqSampleSize is implemented in R language and can be installed from Bioconductor website. A user friendly web graphic interface is provided at http://cqs.mc.vanderbilt.edu/shiny/RnaSeqSampleSize/ . RnaSeqSampleSize provides a convenient and powerful way for power and sample size estimation for an RNAseq experiment. It is also equipped with several unique features, including estimation for interested genes or pathway, power curve visualization, and parameter optimization.

The special case of the 2 × 2 table: asymptotic unconditional McNemar test can be used to estimate sample size even for analysis based on GEE.

PubMed

Borkhoff, Cornelia M; Johnston, Patrick R; Stephens, Derek; Atenafu, Eshetu

2015-07-01

Aligning the method used to estimate sample size with the planned analytic method ensures the sample size needed to achieve the planned power. When using generalized estimating equations (GEE) to analyze a paired binary primary outcome with no covariates, many use an exact McNemar test to calculate sample size. We reviewed the approaches to sample size estimation for paired binary data and compared the sample size estimates on the same numerical examples. We used the hypothesized sample proportions for the 2 × 2 table to calculate the correlation between the marginal proportions to estimate sample size based on GEE. We solved the inside proportions based on the correlation and the marginal proportions to estimate sample size based on exact McNemar, asymptotic unconditional McNemar, and asymptotic conditional McNemar. The asymptotic unconditional McNemar test is a good approximation of GEE method by Pan. The exact McNemar is too conservative and yields unnecessarily large sample size estimates than all other methods. In the special case of a 2 × 2 table, even when a GEE approach to binary logistic regression is the planned analytic method, the asymptotic unconditional McNemar test can be used to estimate sample size. We do not recommend using an exact McNemar test. Copyright © 2015 Elsevier Inc. All rights reserved.

Using a higher criticism statistic to detect modest effects in a genome-wide study of rheumatoid arthritis

PubMed Central

2009-01-01

In high-dimensional studies such as genome-wide association studies, the correction for multiple testing in order to control total type I error results in decreased power to detect modest effects. We present a new analytical approach based on the higher criticism statistic that allows identification of the presence of modest effects. We apply our method to the genome-wide study of rheumatoid arthritis provided in the Genetic Analysis Workshop 16 Problem 1 data set. There is evidence for unknown bias in this study that could be explained by the presence of undetected modest effects. We compared the asymptotic and empirical thresholds for the higher criticism statistic. Using the asymptotic threshold we detected the presence of modest effects genome-wide. We also detected modest effects using 90th percentile of the empirical null distribution as a threshold; however, there is no such evidence when the 95th and 99th percentiles were used. While the higher criticism method suggests that there is some evidence for modest effects, interpreting individual single-nucleotide polymorphisms with significant higher criticism statistics is of undermined value. The goal of higher criticism is to alert the researcher that genetic effects remain to be discovered and to promote the use of more targeted and powerful studies to detect the remaining effects. PMID:20018032

Non-suicidal self-injury and life stress: A systematic meta-analysis and theoretical elaboration

PubMed Central

Liu, Richard T.; Cheek, Shayna M.; Nestor, Bridget A.

2016-01-01

Recent years have seen a considerable growth of interest in the study of life stress and non-suicidal self-injury (NSSI). The current article presents a systematic review of the empirical literature on this association. In addition to providing a comprehensive meta-analysis, the current article includes a qualitative review of the findings for which there were too few cases (i.e., < 3) for reliable approximations of effect sizes. Across the studies included in the meta-analysis, a significant but modest relation between life stress and NSSI was found (pooled OR = 1.81 [95% CI = 1.49–2.21]). After an adjustment was made for publication bias, the estimated effect size was smaller but still significant (pooled OR = 1.33 [95% CI = 1.08–1.63]). This relation was moderated by sample type, NSSI measure type, and length of period covered by the NSSI measure. The empirical literature is characterized by several methodological limitations, particularly the frequent use of cross-sectional analyses involving temporal overlap between assessments of life stress and NSSI, leaving unclear the precise nature of the relation between these two phenomena (e.g., whether life stress may be a cause, concomitant, or consequence of NSSI). Theoretically informed research utilizing multi-wave designs, assessing life stress and NSSI over relatively brief intervals, and featuring interview-based assessments of these constructs holds promise for advancing our understanding of their relation. The current review concludes with a theoretical elaboration of the association between NSSI and life stress, with the aim of providing a conceptual framework to guide future study in this area. PMID:27267345

Fusion positron emission/computed tomography underestimates the presence of hilar nodal metastases in patients with resected non-small cell lung cancer.

PubMed

Carrillo, Sergio A; Daniel, Vincent C; Hall, Nathan; Hitchcock, Charles L; Ross, Patrick; Kassis, Edmund S

2012-05-01

The 5-year survival for patients with resected stage II (N1) non-small cell lung cancer ranges from 40% to 55%. No data exist addressing the benefit of neoadjuvant therapy for patients with stage II disease. This is largely in part due to the lack of a reliable, minimally invasive method to assess hilar nodes. This study is aimed at determining the ability of fusion positron emission/computed tomography (PET/CT) to identify hilar metastases in patients with resected non-small cell lung cancer. A retrospective review of surgically resected patients with fusion PET/CT within 30 days of resection was performed. The sensitivity, specificity, positive predictive value, and negative predictive value for PET/CT in detecting hilar nodal metastases was calculated for a range of maximum standardized uptake values (SUVmax). Hilar nodes from patients with falsely positive PET/CT scans were analyzed for the presence of histoplasmosis. Additionally, the impact of hilar node size greater than 1 centimeter on the calculated values was assessed. There were 119 patients evaluated. The number of lymph nodes resected ranged from 1 to 12 (X=2.98). There was decreased sensitivity and increased specificity with higher SUVmax cutoff values. At the standard SUVmax value of 2.5, the sensitivity and specificity were only 48.5% and 80.2%. The addition of size of hilar node by CT led to a modest improvement in sensitivity at all SUVmax cutoff values. Fusion PET/CT lacks sensitivity and specificity in identifying hilar nodal metastasis in patients with resected non-small cell lung cancer. Further prospective studies assessing the utility of PET/CT versus alternative sampling techniques are warranted. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

The Interactive Role of Immature Stage Competition, Cohort Overlap, and Resource Limitation on the Population Viability of the Treehole Mosquito Aedes triseriatus (Diptera: Culicidae).

PubMed

Hanly, Patrick J; Haase, Amanda T

2016-05-01

The size and success of epidemiologically significant adult mosquito populations are inherently tied to the conditions of the aquatic habitat in which juvenile stages grow until eclosion. While resource competition and quality are well-established controls to juvenile growth and survival, the implications to overall population rates of increase are less understood due to the large sample sizes needed to parameterize population models for all five juvenile life stages under multiple environmental and demographic conditions. Here, we present the results of >4,300 trials of wild-caught Aedes triseriatus (Say, 1823) larvae and pupae reared under varying resource quantity crossed by the presence or absence of competition within a single cohort as well as multiple overlapping cohorts. Demographic projection was used to make predictions of the realized growth rates of simulated Ae. triseriatus populations across the range of potential Ae. triseriatus fecundity. Further, to inform control efforts on juvenile habitat, we constructed a stochastic simulation to estimate the rates of successful emergence from habitats under different resource regimes and levels of cohort overlap. We found that while Ae. triseriatus populations were robust to low resource levels and competition within a cohort, the combination of these stressors with multiple cohort overlap led to self-limitation or complete collapse of mosquito populations. Despite this importance of intraspecific competition to population viability, the stochastic simulation revealed only a modest self-limitation of adult emergence, with the clear implication that high-resource habitats are a higher value control target. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Reporting of sample size calculations in analgesic clinical trials: ACTTION systematic review.

PubMed

McKeown, Andrew; Gewandter, Jennifer S; McDermott, Michael P; Pawlowski, Joseph R; Poli, Joseph J; Rothstein, Daniel; Farrar, John T; Gilron, Ian; Katz, Nathaniel P; Lin, Allison H; Rappaport, Bob A; Rowbotham, Michael C; Turk, Dennis C; Dworkin, Robert H; Smith, Shannon M

2015-03-01

Sample size calculations determine the number of participants required to have sufficiently high power to detect a given treatment effect. In this review, we examined the reporting quality of sample size calculations in 172 publications of double-blind randomized controlled trials of noninvasive pharmacologic or interventional (ie, invasive) pain treatments published in European Journal of Pain, Journal of Pain, and Pain from January 2006 through June 2013. Sixty-five percent of publications reported a sample size calculation but only 38% provided all elements required to replicate the calculated sample size. In publications reporting at least 1 element, 54% provided a justification for the treatment effect used to calculate sample size, and 24% of studies with continuous outcome variables justified the variability estimate. Publications of clinical pain condition trials reported a sample size calculation more frequently than experimental pain model trials (77% vs 33%, P < .001) but did not differ in the frequency of reporting all required elements. No significant differences in reporting of any or all elements were detected between publications of trials with industry and nonindustry sponsorship. Twenty-eight percent included a discrepancy between the reported number of planned and randomized participants. This study suggests that sample size calculation reporting in analgesic trial publications is usually incomplete. Investigators should provide detailed accounts of sample size calculations in publications of clinical trials of pain treatments, which is necessary for reporting transparency and communication of pre-trial design decisions. In this systematic review of analgesic clinical trials, sample size calculations and the required elements (eg, treatment effect to be detected; power level) were incompletely reported. A lack of transparency regarding sample size calculations may raise questions about the appropriateness of the calculated sample size. Copyright © 2015 American Pain Society. All rights reserved.

A Modest Critical Pedagogy for English as a Foreign Language Education

ERIC Educational Resources Information Center

Kim, Mi Kyong; Pollard, Vikki Ann

2017-01-01

This paper uses the introduction of critical pedagogy to an English as a Foreign Language class in the Republic of Korea as a case study for a "modest critical pedagogy" (Tinning 2002). Focusing on the stress and resistances experienced during the introduction, we suggest a modest critical pedagogy that 1) makes the paradigm itself an…

Determination of the optimal sample size for a clinical trial accounting for the population size.

PubMed

Stallard, Nigel; Miller, Frank; Day, Simon; Hee, Siew Wan; Madan, Jason; Zohar, Sarah; Posch, Martin

2017-07-01

The problem of choosing a sample size for a clinical trial is a very common one. In some settings, such as rare diseases or other small populations, the large sample sizes usually associated with the standard frequentist approach may be infeasible, suggesting that the sample size chosen should reflect the size of the population under consideration. Incorporation of the population size is possible in a decision-theoretic approach either explicitly by assuming that the population size is fixed and known, or implicitly through geometric discounting of the gain from future patients reflecting the expected population size. This paper develops such approaches. Building on previous work, an asymptotic expression is derived for the sample size for single and two-arm clinical trials in the general case of a clinical trial with a primary endpoint with a distribution of one parameter exponential family form that optimizes a utility function that quantifies the cost and gain per patient as a continuous function of this parameter. It is shown that as the size of the population, N, or expected size, N∗ in the case of geometric discounting, becomes large, the optimal trial size is O(N1/2) or O(N∗1/2). The sample size obtained from the asymptotic expression is also compared with the exact optimal sample size in examples with responses with Bernoulli and Poisson distributions, showing that the asymptotic approximations can also be reasonable in relatively small sample sizes. © 2016 The Author. Biometrical Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Birth order effects on nonverbal IQ scores in autism multiplex families.

PubMed

Spiker, D; Lotspeich, L J; Dimiceli, S; Szatmari, P; Myers, R M; Risch, N

2001-10-01

Lord (1992) published a brief report showing a trend for decreasing nonverbal IQ scores with increasing birth order in a sample of 16 autism multiplex families, and urged replication in a larger sample. In this report, analyses of nonverbal IQ scores for a sample of 144 autism multiplex families indicated that nonverbal IQ scores were significantly lower in secondborn compared with firstborn siblings with autism. This birth order effect was independent of gender as well as the age differences within sib pairs. No such birth order effects were found for social or communicative deficits as measured by the Autism Diagnostic Interview-Revised (ADI-R), but there was a modest tendency for increased scores for ritualistic behaviors for the firstborn sibs. Further, there were no gender differences on nonverbal IQ scores in this sample. Results are discussed in terms of implications for genetic studies of autism.

Requirements for Minimum Sample Size for Sensitivity and Specificity Analysis

PubMed Central

Adnan, Tassha Hilda

2016-01-01

Sensitivity and specificity analysis is commonly used for screening and diagnostic tests. The main issue researchers face is to determine the sufficient sample sizes that are related with screening and diagnostic studies. Although the formula for sample size calculation is available but concerning majority of the researchers are not mathematicians or statisticians, hence, sample size calculation might not be easy for them. This review paper provides sample size tables with regards to sensitivity and specificity analysis. These tables were derived from formulation of sensitivity and specificity test using Power Analysis and Sample Size (PASS) software based on desired type I error, power and effect size. The approaches on how to use the tables were also discussed. PMID:27891446

Some ways in which neighborhoods, nuclear families, friendship groups, and schools jointly affect changes in early adolescent development.

PubMed

Cook, Thomas D; Herman, Melissa R; Phillips, Meredith; Settersten, Richard A

2002-01-01

This study assessed some ways in which schools, neighborhoods, nuclear families, and friendship groups jointly contribute to positive change during early adolescence. For each context, existing theory was used to develop a multiattribute index that should promote successful development. Descriptive analyses showed that the four resulting context indices were only modestly intercorrelated at the individual student level (N = 12,398), but clustered more tightly at the school and neighborhood levels (N = 23 and 151 respectively). Only for aggregated units did knowing the developmental capacity of any one context strongly predict the corresponding capacity of the other contexts. Analyses also revealed that each context facilitated individual change in a success index that tapped into student academic performance, mental health, and social behavior. However, individual context effects were only modest in size over the 19 months studied and did not vary much by context. The joint influence of all four contexts was cumulatively large, however, and because it was generally additive in form, no constellation of contexts was identified whose total effect reliably surpassed the sum of its individual context main effects. These results suggest that achieving significant population changes in multidimensional student growth during early adolescence most likely requires both theory and interventions that are explicitly pan-contextual.

Sample size calculations for randomized clinical trials published in anesthesiology journals: a comparison of 2010 versus 2016.

PubMed

Chow, Jeffrey T Y; Turkstra, Timothy P; Yim, Edmund; Jones, Philip M

2018-06-01

Although every randomized clinical trial (RCT) needs participants, determining the ideal number of participants that balances limited resources and the ability to detect a real effect is difficult. Focussing on two-arm, parallel group, superiority RCTs published in six general anesthesiology journals, the objective of this study was to compare the quality of sample size calculations for RCTs published in 2010 vs 2016. Each RCT's full text was searched for the presence of a sample size calculation, and the assumptions made by the investigators were compared with the actual values observed in the results. Analyses were only performed for sample size calculations that were amenable to replication, defined as using a clearly identified outcome that was continuous or binary in a standard sample size calculation procedure. The percentage of RCTs reporting all sample size calculation assumptions increased from 51% in 2010 to 84% in 2016. The difference between the values observed in the study and the expected values used for the sample size calculation for most RCTs was usually > 10% of the expected value, with negligible improvement from 2010 to 2016. While the reporting of sample size calculations improved from 2010 to 2016, the expected values in these sample size calculations often assumed effect sizes larger than those actually observed in the study. Since overly optimistic assumptions may systematically lead to underpowered RCTs, improvements in how to calculate and report sample sizes in anesthesiology research are needed.

Cryogen spray cooling: Effects of droplet size and spray density on heat removal.

PubMed

Pikkula, B M; Torres, J H; Tunnell, J W; Anvari, B

2001-01-01

Cryogen spray cooling (CSC) is an effective method to reduce or eliminate non-specific injury to the epidermis during laser treatment of various dermatological disorders. In previous CSC investigations, fuel injectors have been used to deliver the cryogen onto the skin surface. The objective of this study was to examine cryogen atomization and heat removal characteristics of various cryogen delivery devices. Various cryogen delivery device types including fuel injectors, atomizers, and a device currently used in clinical settings were investigated. Cryogen mass was measured at the delivery device output orifice. Cryogen droplet size profiling for various cryogen delivery devices was estimated by optically imaging the droplets in flight. Heat removal for various cryogen delivery devices was estimated over a range of spraying distances by temperature measurements in an skin phantom used in conjunction with an inverse heat conduction model. A substantial range of mass outputs were measured for the cryogen delivery devices while heat removal varied by less than a factor of two. Droplet profiling demonstrated differences in droplet size and spray density. Results of this study show that variation in heat removal by different cryogen delivery devices is modest despite the relatively large difference in cryogen mass output and droplet size. A non-linear relationship between heat removal by various devices and droplet size and spray density was observed. Copyright 2001 Wiley-Liss, Inc.

The Classification of Universes

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

Bjorken, J

2004-04-09

We define a universe as the contents of a spacetime box with comoving walls, large enough to contain essentially all phenomena that can be conceivably measured. The initial time is taken as the epoch when the lowest CMB modes undergo horizon crossing, and the final time taken when the wavelengths of CMB photons are comparable with the Hubble scale, i.e. with the nominal size of the universe. This allows the definition of a local ensemble of similarly constructed universes, using only modest extrapolations of the observed behavior of the cosmos. We then assume that further out in spacetime, similar universesmore » can be constructed but containing different standard model parameters. Within this multiverse ensemble, it is assumed that the standard model parameters are strongly correlated with size, i.e. with the value of the inverse Hubble parameter at the final time, in a manner as previously suggested. This allows an estimate of the range of sizes which allow life as we know it, and invites a speculation regarding the most natural distribution of sizes. If small sizes are favored, this in turn allows some understanding of the hierarchy problems of particle physics. Subsequent sections of the paper explore other possible implications. In all cases, the approach is as bottoms up and as phenomenological as possible, and suggests that theories of the multiverse so constructed may in fact lay some claim of being scientific.« less

Transparent EuTiO3 films: a possible two-dimensional magneto-optical device

NASA Astrophysics Data System (ADS)

Bussmann-Holder, Annette; Roleder, Krystian; Stuhlhofer, Benjamin; Logvenov, Gennady; Lazar, Iwona; Soszyński, Andrzej; Koperski, Janusz; Simon, Arndt; Köhler, Jürgen

2017-01-01

The magneto-optical activity of high quality transparent thin films of insulating EuTiO3 (ETO) deposited on a thin SrTiO3 (STO) substrate, both being non-magnetic materials, are demonstrated to be a versatile tool for light modulation. The operating temperature is close to room temperature and allows for multiple device engineering. By using small magnetic fields birefringence of the samples can be switched off and on. Similarly, rotation of the sample in the field can modify its birefringence Δn. In addition, Δn can be increased by a factor of 4 in very modest fields with simultaneously enhancing the operating temperature by almost 100 K.

An Employee Total Health Management–Based Survey of Iowa Employers

PubMed Central

Merchant, James A.; Lind, David P.; Kelly, Kevin M.; Hall, Jennifer L.

2015-01-01

Objective To implement an Employee Total Health Management (ETHM) model-based questionnaire and provide estimates of model program elements among a statewide sample of Iowa employers. Methods Survey a stratified random sample of Iowa employers, characterize and estimate employer participation in ETHM program elements Results Iowa employers are implementing under 30% of all 12 components of ETHM, with the exception of occupational safety and health (46.6%) and worker compensation insurance coverage (89.2%), but intend modest expansion of all components in the coming year. Conclusions The Employee Total Health Management questionnaire-based survey provides estimates of progress Iowa employers are making toward implementing components of total worker health programs. PMID:24284757

Bidirectional Relationships Between Parenting Processes and Deviance in a Sample of Inner-City African American Youth

PubMed Central

Harris, Charlene; Vazsonyi, Alexander T.; Bolland, John M.

2016-01-01

The current study assessed for bidirectional relationships among supportive parenting (knowledge), negative parenting (permissiveness), and deviance in a sample (N = 5,325) of poor, inner-city African American youth from the Mobile Youth Survey (MYS) over 4 years. Cross-lagged path analysis provided evidence of significant bidirectional paths among parenting processes (knowledge and permissiveness) and deviance over time. Follow-up multigroup tests provided only modest evidence of dissimilar relationships by sex and by developmental periods. The findings improve our understanding of developmental changes between parenting behaviors and deviance during adolescence and extended current research of the bidirectionality of parent and child relationships among inner-city African American youth. PMID:28316460

Effects of Scan Resolutions and Element Sizes on Bovine Vertebral Mechanical Parameters from Quantitative Computed Tomography-Based Finite Element Analysis

PubMed Central

Zhang, Meng; Gao, Jiazi; Huang, Xu; Zhang, Min; Liu, Bei

2017-01-01

Quantitative computed tomography-based finite element analysis (QCT/FEA) has been developed to predict vertebral strength. However, QCT/FEA models may be different with scan resolutions and element sizes. The aim of this study was to explore the effects of scan resolutions and element sizes on QCT/FEA outcomes. Nine bovine vertebral bodies were scanned using the clinical CT scanner and reconstructed from datasets with the two-slice thickness, that is, 0.6 mm (PA resolution) and 1 mm (PB resolution). There were significantly linear correlations between the predicted and measured principal strains (R2 > 0.7, P < 0.0001), and the predicted vertebral strength and stiffness were modestly correlated with the experimental values (R2 > 0.6, P < 0.05). Two different resolutions and six different element sizes were combined in pairs, and finite element (FE) models of bovine vertebral cancellous bones in the 12 cases were obtained. It showed that the mechanical parameters of FE models with the PB resolution were similar to those with the PA resolution. The computational accuracy of FE models with the element sizes of 0.41 × 0.41 × 0.6 mm3 and 0.41 × 0.41 × 1 mm3 was higher by comparing the apparent elastic modulus and yield strength. Therefore, scan resolution and element size should be chosen optimally to improve the accuracy of QCT/FEA. PMID:29065624

Mechanisms regulating nutrition-dependent developmental plasticity through organ-specific effects in insects

PubMed Central

Koyama, Takashi; Mendes, Cláudia C.; Mirth, Christen K.

2013-01-01

Nutrition, via the insulin/insulin-like growth factor (IIS)/Target of Rapamycin (TOR) signaling pathway, can provide a strong molding force for determining animal size and shape. For instance, nutrition induces a disproportionate increase in the size of male horns in dung and rhinoceros beetles, or mandibles in staghorn or horned flour beetles, relative to body size. In these species, well-fed male larvae produce adults with greatly enlarged horns or mandibles, whereas males that are starved or poorly fed as larvae bear much more modest appendages. Changes in IIS/TOR signaling plays a key role in appendage development by regulating growth in the horn and mandible primordia. In contrast, changes in the IIS/TOR pathway produce minimal effects on the size of other adult structures, such as the male genitalia in fruit flies and dung beetles. The horn, mandible and genitalia illustrate that although all tissues are exposed to the same hormonal environment within the larval body, the extent to which insulin can induce growth is organ specific. In addition, the IIS/TOR pathway affects body size and shape by controlling production of metamorphic hormones important for regulating developmental timing, like the steroid molting hormone ecdysone and sesquiterpenoid hormone juvenile hormone. In this review, we discuss recent results from Drosophila and other insects that highlight mechanisms allowing tissues to differ in their sensitivity to IIS/TOR and the potential consequences of these differences on body size and shape. PMID:24133450

Sample Size and Statistical Conclusions from Tests of Fit to the Rasch Model According to the Rasch Unidimensional Measurement Model (Rumm) Program in Health Outcome Measurement.

PubMed

Hagell, Peter; Westergren, Albert

Sample size is a major factor in statistical null hypothesis testing, which is the basis for many approaches to testing Rasch model fit. Few sample size recommendations for testing fit to the Rasch model concern the Rasch Unidimensional Measurement Models (RUMM) software, which features chi-square and ANOVA/F-ratio based fit statistics, including Bonferroni and algebraic sample size adjustments. This paper explores the occurrence of Type I errors with RUMM fit statistics, and the effects of algebraic sample size adjustments. Data with simulated Rasch model fitting 25-item dichotomous scales and sample sizes ranging from N = 50 to N = 2500 were analysed with and without algebraically adjusted sample sizes. Results suggest the occurrence of Type I errors with N less then or equal to 500, and that Bonferroni correction as well as downward algebraic sample size adjustment are useful to avoid such errors, whereas upward adjustment of smaller samples falsely signal misfit. Our observations suggest that sample sizes around N = 250 to N = 500 may provide a good balance for the statistical interpretation of the RUMM fit statistics studied here with respect to Type I errors and under the assumption of Rasch model fit within the examined frame of reference (i.e., about 25 item parameters well targeted to the sample).

Genetics of Rapid and Extreme Size Evolution in Island Mice

PubMed Central

Gray, Melissa M.; Parmenter, Michelle D.; Hogan, Caley A.; Ford, Irene; Cuthbert, Richard J.; Ryan, Peter G.; Broman, Karl W.; Payseur, Bret A.

2015-01-01

Organisms on islands provide a revealing window into the process of adaptation. Populations that colonize islands often evolve substantial differences in body size from their mainland relatives. Although the ecological drivers of this phenomenon have received considerable attention, its genetic basis remains poorly understood. We use house mice (subspecies: Mus musculus domesticus) from remote Gough Island to provide a genetic portrait of rapid and extreme size evolution. In just a few hundred generations, Gough Island mice evolved the largest body size among wild house mice from around the world. Through comparisons with a smaller-bodied wild-derived strain from the same subspecies (WSB/EiJ), we demonstrate that Gough Island mice achieve their exceptional body weight primarily by growing faster during the 6 weeks after birth. We use genetic mapping in large F2 intercrosses between Gough Island mice and WSB/EiJ to identify 19 quantitative trait loci (QTL) responsible for the evolution of 16-week weight trajectories: 8 QTL for body weight and 11 QTL for growth rate. QTL exhibit modest effects that are mostly additive. We conclude that body size evolution on islands can be genetically complex, even when substantial size changes occur rapidly. In comparisons to published studies of laboratory strains of mice that were artificially selected for divergent body sizes, we discover that the overall genetic profile of size evolution in nature and in the laboratory is similar, but many contributing loci are distinct. Our results underscore the power of genetically characterizing the entire growth trajectory in wild populations and lay the foundation necessary for identifying the mutations responsible for extreme body size evolution in nature. PMID:26199233

Genetics of Rapid and Extreme Size Evolution in Island Mice.

PubMed

Gray, Melissa M; Parmenter, Michelle D; Hogan, Caley A; Ford, Irene; Cuthbert, Richard J; Ryan, Peter G; Broman, Karl W; Payseur, Bret A

2015-09-01

Organisms on islands provide a revealing window into the process of adaptation. Populations that colonize islands often evolve substantial differences in body size from their mainland relatives. Although the ecological drivers of this phenomenon have received considerable attention, its genetic basis remains poorly understood. We use house mice (subspecies: Mus musculus domesticus) from remote Gough Island to provide a genetic portrait of rapid and extreme size evolution. In just a few hundred generations, Gough Island mice evolved the largest body size among wild house mice from around the world. Through comparisons with a smaller-bodied wild-derived strain from the same subspecies (WSB/EiJ), we demonstrate that Gough Island mice achieve their exceptional body weight primarily by growing faster during the 6 weeks after birth. We use genetic mapping in large F(2) intercrosses between Gough Island mice and WSB/EiJ to identify 19 quantitative trait loci (QTL) responsible for the evolution of 16-week weight trajectories: 8 QTL for body weight and 11 QTL for growth rate. QTL exhibit modest effects that are mostly additive. We conclude that body size evolution on islands can be genetically complex, even when substantial size changes occur rapidly. In comparisons to published studies of laboratory strains of mice that were artificially selected for divergent body sizes, we discover that the overall genetic profile of size evolution in nature and in the laboratory is similar, but many contributing loci are distinct. Our results underscore the power of genetically characterizing the entire growth trajectory in wild populations and lay the foundation necessary for identifying the mutations responsible for extreme body size evolution in nature. Copyright © 2015 by the Genetics Society of America.

Visual search for arbitrary objects in real scenes

PubMed Central

Alvarez, George A.; Rosenholtz, Ruth; Kuzmova, Yoana I.; Sherman, Ashley M.

2011-01-01

How efficient is visual search in real scenes? In searches for targets among arrays of randomly placed distractors, efficiency is often indexed by the slope of the reaction time (RT) × Set Size function. However, it may be impossible to define set size for real scenes. As an approximation, we hand-labeled 100 indoor scenes and used the number of labeled regions as a surrogate for set size. In Experiment 1, observers searched for named objects (a chair, bowl, etc.). With set size defined as the number of labeled regions, search was very efficient (~5 ms/item). When we controlled for a possible guessing strategy in Experiment 2, slopes increased somewhat (~15 ms/item), but they were much shallower than search for a random object among other distinctive objects outside of a scene setting (Exp. 3: ~40 ms/item). In Experiments 4–6, observers searched repeatedly through the same scene for different objects. Increased familiarity with scenes had modest effects on RTs, while repetition of target items had large effects (>500 ms). We propose that visual search in scenes is efficient because scene-specific forms of attentional guidance can eliminate most regions from the “functional set size” of items that could possibly be the target. PMID:21671156

Steep Delay Discounting and Addictive Behavior: A Meta-Analysis of Continuous Associations

PubMed Central

Amlung, Michael; Vedelago, Lana; Acker, John; Balodis, Iris; MacKillop, James

2016-01-01

Aims To synthesize continuous associations between delayed reward discounting (DRD) and both addiction severity and quantity-frequency (QF); to examine moderators of these relationships; and to investigate publication bias. Methods Meta-analysis of published studies examining continuous associations between DRD and addictive behaviors. Published, peer-reviewed studies on addictive behaviors (alcohol, tobacco, cannabis, stimulants, opiates, and gambling) were identified via PubMed, MEDLINE, and PsycInfo. Studies were restricted to DRD measures of monetary gains. Random effects meta-analysis was conducted using Pearson’s r as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger’s tests, meta-regression of publication year and effect size, and imputation of missing studies. Results The primary meta-analysis revealed a small magnitude effect size that was highly significant (r = 0.14, p < 10−14). Significantly larger effect sizes were observed for studies examining severity compared with QF (p = 0.01), but not between the type of addictive behavior (p = 0.30) or DRD assessment (p = 0.90). Indices of publication bias suggested a modest impact of unpublished findings. Conclusions Delayed reward discounting is robustly associated with continuous measures of addiction severity and quantity-frequency. This relation is generally robust across type of addictive behavior and delayed reward discounting assessment modality. PMID:27450931

Analysis of methods commonly used in biomedicine for treatment versus control comparison of very small samples.

PubMed

Ristić-Djurović, Jasna L; Ćirković, Saša; Mladenović, Pavle; Romčević, Nebojša; Trbovich, Alexander M

2018-04-01

A rough estimate indicated that use of samples of size not larger than ten is not uncommon in biomedical research and that many of such studies are limited to strong effects due to sample sizes smaller than six. For data collected from biomedical experiments it is also often unknown if mathematical requirements incorporated in the sample comparison methods are satisfied. Computer simulated experiments were used to examine performance of methods for qualitative sample comparison and its dependence on the effectiveness of exposure, effect intensity, distribution of studied parameter values in the population, and sample size. The Type I and Type II errors, their average, as well as the maximal errors were considered. The sample size 9 and the t-test method with p = 5% ensured error smaller than 5% even for weak effects. For sample sizes 6-8 the same method enabled detection of weak effects with errors smaller than 20%. If the sample sizes were 3-5, weak effects could not be detected with an acceptable error; however, the smallest maximal error in the most general case that includes weak effects is granted by the standard error of the mean method. The increase of sample size from 5 to 9 led to seven times more accurate detection of weak effects. Strong effects were detected regardless of the sample size and method used. The minimal recommended sample size for biomedical experiments is 9. Use of smaller sizes and the method of their comparison should be justified by the objective of the experiment. Copyright © 2018 Elsevier B.V. All rights reserved.

Differences in pain, function and coping in Multidimensional Pain Inventory subgroups of chronic back pain: a one-group pretest-posttest study.

PubMed

Verra, Martin L; Angst, Felix; Staal, J Bart; Brioschi, Roberto; Lehmann, Susanne; Aeschlimann, André; de Bie, Rob A

2011-06-30

Patients with non-specific back pain are not a homogeneous group but heterogeneous with regard to their bio-psycho-social impairments. This study examined a sample of 173 highly disabled patients with chronic back pain to find out how the three subgroups based on the Multidimensional Pain Inventory (MPI) differed in their response to an inpatient pain management program. Subgroup classification was conducted by cluster analysis using MPI subscale scores at entry into the program. At program entry and at discharge after four weeks, participants completed the MPI, the MOS Short Form-36 (SF-36), the Hospital Anxiety and Depression Scale (HADS), and the Coping Strategies Questionnaire (CSQ). Pairwise analyses of the score changes of the mentioned outcomes of the three MPI subgroups were performed using the Mann-Whitney-U-test for significance. Cluster analysis identified three MPI subgroups in this highly disabled sample: a dysfunctional, interpersonally distressed and an adaptive copers subgroup. The dysfunctional subgroup (29% of the sample) showed the highest level of depression in SF-36 mental health (33.4 ± 13.9), the interpersonally distressed subgroup (35% of the sample) a modest level of depression (46.8 ± 20.4), and the adaptive copers subgroup (32% of the sample) the lowest level of depression (57.8 ± 19.1). Significant differences in pain reduction and improvement of mental health and coping were observed across the three MPI subgroups, i.e. the effect sizes for MPI pain reduction were: 0.84 (0.44-1.24) for the dysfunctional subgroup, 1.22 (0.86-1.58) for the adaptive copers subgroup, and 0.53 (0.24-0.81) for the interpersonally distressed subgroup (p = 0.006 for pairwise comparison). Significant score changes between subgroups concerning activities and physical functioning could not be identified. MPI subgroup classification showed significant differences in score changes for pain, mental health and coping. These findings underscore the importance of assessing individual differences to understand how patients adjust to chronic back pain.

Sample size determination for estimating antibody seroconversion rate under stable malaria transmission intensity.

PubMed

Sepúlveda, Nuno; Drakeley, Chris

2015-04-03

In the last decade, several epidemiological studies have demonstrated the potential of using seroprevalence (SP) and seroconversion rate (SCR) as informative indicators of malaria burden in low transmission settings or in populations on the cusp of elimination. However, most of studies are designed to control ensuing statistical inference over parasite rates and not on these alternative malaria burden measures. SP is in essence a proportion and, thus, many methods exist for the respective sample size determination. In contrast, designing a study where SCR is the primary endpoint, is not an easy task because precision and statistical power are affected by the age distribution of a given population. Two sample size calculators for SCR estimation are proposed. The first one consists of transforming the confidence interval for SP into the corresponding one for SCR given a known seroreversion rate (SRR). The second calculator extends the previous one to the most common situation where SRR is unknown. In this situation, data simulation was used together with linear regression in order to study the expected relationship between sample size and precision. The performance of the first sample size calculator was studied in terms of the coverage of the confidence intervals for SCR. The results pointed out to eventual problems of under or over coverage for sample sizes ≤250 in very low and high malaria transmission settings (SCR ≤ 0.0036 and SCR ≥ 0.29, respectively). The correct coverage was obtained for the remaining transmission intensities with sample sizes ≥ 50. Sample size determination was then carried out for cross-sectional surveys using realistic SCRs from past sero-epidemiological studies and typical age distributions from African and non-African populations. For SCR < 0.058, African studies require a larger sample size than their non-African counterparts in order to obtain the same precision. The opposite happens for the remaining transmission intensities. With respect to the second sample size calculator, simulation unravelled the likelihood of not having enough information to estimate SRR in low transmission settings (SCR ≤ 0.0108). In that case, the respective estimates tend to underestimate the true SCR. This problem is minimized by sample sizes of no less than 500 individuals. The sample sizes determined by this second method highlighted the prior expectation that, when SRR is not known, sample sizes are increased in relation to the situation of a known SRR. In contrast to the first sample size calculation, African studies would now require lesser individuals than their counterparts conducted elsewhere, irrespective of the transmission intensity. Although the proposed sample size calculators can be instrumental to design future cross-sectional surveys, the choice of a particular sample size must be seen as a much broader exercise that involves weighting statistical precision with ethical issues, available human and economic resources, and possible time constraints. Moreover, if the sample size determination is carried out on varying transmission intensities, as done here, the respective sample sizes can also be used in studies comparing sites with different malaria transmission intensities. In conclusion, the proposed sample size calculators are a step towards the design of better sero-epidemiological studies. Their basic ideas show promise to be applied to the planning of alternative sampling schemes that may target or oversample specific age groups.

Using known populations of pronghorn to evaluate sampling plans and estimators

USGS Publications Warehouse

Kraft, K.M.; Johnson, D.H.; Samuelson, J.M.; Allen, S.H.

1995-01-01

Although sampling plans and estimators of abundance have good theoretical properties, their performance in real situations is rarely assessed because true population sizes are unknown. We evaluated widely used sampling plans and estimators of population size on 3 known clustered distributions of pronghorn (Antilocapra americana). Our criteria were accuracy of the estimate, coverage of 95% confidence intervals, and cost. Sampling plans were combinations of sampling intensities (16, 33, and 50%), sample selection (simple random sampling without replacement, systematic sampling, and probability proportional to size sampling with replacement), and stratification. We paired sampling plans with suitable estimators (simple, ratio, and probability proportional to size). We used area of the sampling unit as the auxiliary variable for the ratio and probability proportional to size estimators. All estimators were nearly unbiased, but precision was generally low (overall mean coefficient of variation [CV] = 29). Coverage of 95% confidence intervals was only 89% because of the highly skewed distribution of the pronghorn counts and small sample sizes, especially with stratification. Stratification combined with accurate estimates of optimal stratum sample sizes increased precision, reducing the mean CV from 33 without stratification to 25 with stratification; costs increased 23%. Precise results (mean CV = 13) but poor confidence interval coverage (83%) were obtained with simple and ratio estimators when the allocation scheme included all sampling units in the stratum containing most pronghorn. Although areas of the sampling units varied, ratio estimators and probability proportional to size sampling did not increase precision, possibly because of the clumped distribution of pronghorn. Managers should be cautious in using sampling plans and estimators to estimate abundance of aggregated populations.

Evaluation of an Online Platform for Multiple Sclerosis Research: Patient Description, Validation of Severity Scale, and Exploration of BMI Effects on Disease Course

PubMed Central

Bove, Riley; Secor, Elizabeth; Healy, Brian C.; Musallam, Alexander; Vaughan, Timothy; Glanz, Bonnie I.; Greeke, Emily; Weiner, Howard L.; Chitnis, Tanuja; Wicks, Paul; De Jager, Philip L.

2013-01-01

Objectives To assess the potential of an online platform, PatientsLikeMe.com (PLM), for research in multiple sclerosis (MS). An investigation of the role of body mass index (BMI) on MS disease course was conducted to illustrate the utility of the platform. Methods First, we compared the demographic characteristics of subjects from PLM and from a regional MS center. Second, we validated PLM’s patient-reported outcome measure (MS Rating Scale, MSRS) against standard physician-rated tools. Finally, we analyzed the relation of BMI to the MSRS measure. Results Compared with 4,039 MS Center patients, the 10,255 PLM members were younger, more educated, and less often male and white. Disease course was more often relapsing remitting, with younger symptom onset and shorter disease duration. Differences were significant because of large sample sizes but small in absolute terms. MSRS scores for 121 MS Center patients revealed acceptable agreement between patient-derived and physician-derived composite scores (weighted kappa = 0.46). The Walking domain showed the highest weighted kappa (0.73) and correlation (rs = 0.86) between patient and physician scores. Additionally, there were good correlations between the patient-reported MSRS composite and walking scores and physician-derived measures: Expanded Disability Status Scale (composite rs = 0.61, walking rs = 0.74), Timed 25 Foot Walk (composite rs = 0.70, walking rs = 0.69), and Ambulation Index (composite rs = 0.81, walking rs = 0.84). Finally, using PLM data, we found a modest correlation between BMI and cross-sectional MSRS (rho = 0.17) and no association between BMI and disease course. Conclusions The PLM population is comparable to a clinic population, and its patient-reported MSRS is correlated with existing clinical instruments. Thus, this online platform may provide a venue for MS investigations with unique strengths (frequent data collection, large sample sizes). To illustrate its applicability, we assessed the role of BMI in MS disease course but did not find a clinically meaningful role for BMI in this setting. PMID:23527256

Detailed Abundances of Stars with Small Planets Discovered by Kepler. I. The First Sample

NASA Astrophysics Data System (ADS)

Schuler, Simon C.; Vaz, Zachary A.; Katime Santrich, Orlando J.; Cunha, Katia; Smith, Verne V.; King, Jeremy R.; Teske, Johanna K.; Ghezzi, Luan; Howell, Steve B.; Isaacson, Howard

2015-12-01

We present newly derived stellar parameters and the detailed abundances of 19 elements of seven stars with small planets discovered by NASA's Kepler Mission. Each star, save one, has at least one planet with a radius ≤1.6 R⊕, suggesting a primarily rocky composition. The stellar parameters and abundances are derived from high signal-to-noise ratio, high-resolution echelle spectroscopy obtained with the 10 m Keck I telescope and High Resolution Echelle Spectrometer using standard spectroscopic techniques. The metallicities of the seven stars range from -0.32 to +0.13 dex, with an average metallicity that is subsolar, supporting previous suggestions that, unlike Jupiter-type giant planets, small planets do not form preferentially around metal-rich stars. The abundances of elements other than iron are in line with a population of Galactic disk stars, and despite our modest sample size, we find hints that the compositions of stars with small planets are similar to stars without known planets and with Neptune-size planets, but not to those of stars with giant planets. This suggests that the formation of small planets does not require exceptional host-star compositions and that small planets may be ubiquitous in the Galaxy. We compare our derived abundances (which have typical uncertainties of ≲0.04 dex) to the condensation temperature of the elements; a correlation between the two has been suggested as a possible signature of rocky planet formation. None of the stars demonstrate the putative rocky planet signature, despite at least three of the stars having rocky planets estimated to contain enough refractory material to produce the signature, if real. More detailed abundance analyses of stars known to host small planets are needed to verify our results and place ever more stringent constraints on planet formation models. Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation.

Effect of feature size on dielectric nonlinearity of patterned PbZr{sub 0.52}Ti{sub 0.48}O{sub 3} films

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

Yang, J. I., E-mail: jxy194@psu.edu; Trolier-McKinstry, S.; Polcawich, R. G.

2015-01-07

Lead zirconate titanate, PZT (52/48), thin films with a PbTiO{sub 3} seed layer were patterned into features of different widths, including various sizes of squares and 100 μm, 50 μm, and 10 μm serpentine designs, using argon ion beam milling. Patterns with different surface area/perimeter ratios were used to study the relative importance of damage produced by the patterning. It was found that as the pattern dimensions decreased, the remanent polarization increased, presumably due to the fact that the dipoles near the feature perimeter are not as severely clamped to the substrate. This investigation is in agreement with a model in which clampingmore » produces deep wells, which do not allow some fraction of the spontaneous polarization to switch at high field. The domain wall mobility at modest electric fields was investigated using the Rayleigh law. Both the reversible, ε{sub init}, and irreversible, α, Rayleigh coefficients increased with decreasing serpentine line width for de-aged samples. For measurements made immediately after annealing, ε{sub init} of 500 μm square patterns was 1510 ± 13; with decreasing serpentine line width, ε{sub init} rose from 1520 ± 10 for the 100 μm serpentine to 1568 ± 23 for the 10 μm serpentine. The irreversible parameter, α, for the square patterns was 39.4 ± 3.2 cm/kV and it increased to 44.1 ± 3.2 cm/kV as the lateral dimension is reduced. However, it was found that as the width of the serpentine features decreased, the aging rate rose. These observations are consistent with a model in which sidewall damage produces shallow wells that lower the Rayleigh constants of aged samples at small fields. These shallow wells can be overcome by the large fields used to measure the remanent polarization and the large unipolar electric fields typically used to drive thin film piezoelectric actuators.« less

No effect of modest selenium supplementation on insulin resistance in UK pregnant women, as assessed by plasma adiponectin concentration.

PubMed

Mao, Jinyuan; Bath, Sarah C; Vanderlelie, Jessica J; Perkins, Anthony V; Redman, Christopher W G; Rayman, Margaret P

2016-01-14

Concern has been expressed recently that Se may increase the risk of type 2 diabetes, but this has not been tested in a randomised-controlled trial (RCT) in pregnant women. We took advantage of having stored plasma samples from the Se in Pregnancy Intervention (SPRINT) RCT of Se supplementation in pregnancy to test the effect of Se supplementation on a marker of insulin resistance in UK pregnant women. Because our blood samples were not fasted, we measured plasma adiponectin concentration, a recognised marker of insulin resistance that gives valid measurements in non-fasted samples, as diurnal variability is minor and there is no noticeable effect of food intake. In SPRINT, 230 primiparous UK women were randomised to treatment with Se (60 μg/d) or placebo from 12 weeks of gestation until delivery. We hypothesised that supplementation with Se at a nutritional level would not exacerbate the fall in adiponectin concentration that occurs in normal pregnancy, indicating the lack of an adverse effect on insulin resistance. Indeed, there was no significant difference between the two groups in the change in adiponectin from 12 to 35 weeks (P=0·938), nor when the analysis was restricted to the bottom or top quartiles of baseline whole-blood Se (P=0·515 and 0·858, respectively). Cross-sectionally, adiponectin concentration was not associated with any parameter of Se status, either at 12 or 35 weeks. It is reassuring that a nutritional dose of Se had no adverse effect on the concentration of adiponectin, a biomarker of insulin resistance, in pregnant women of modest Se status.

Association between stressful life events and psychotic experiences in adolescence: evidence for gene–environment correlations

PubMed Central

Shakoor, Sania; Zavos, Helena M. S.; Haworth, Claire M. A.; McGuire, Phillip; Cardno, Alastair G.; Freeman, Daniel; Ronald, Angelica

2016-01-01

Background Stressful life events (SLEs) are associated with psychotic experiences. SLEs might act as an environmental risk factor, but may also share a genetic propensity with psychotic experiences. Aims To estimate the extent to which genetic and environmental factors influence the relationship between SLEs and psychotic experiences. Method Self- and parent reports from a community-based twin sample (4830 16-year-old pairs) were analysed using structural equation model fitting. Results SLEs correlated with positive psychotic experiences (r = 0.12–0.14, all P<0.001). Modest heritability was shown for psychotic experiences (25–57%) and dependent SLEs (32%). Genetic influences explained the majority of the modest covariation between dependent SLEs and paranoia and cognitive disorganisation (bivariate heritabilities 74–86%). The relationship between SLEs and hallucinations and grandiosity was explained by both genetic and common environmental effects. Conclusions Further to dependent SLEs being an environmental risk factor, individuals may have an underlying genetic propensity increasing their risk of dependent SLEs and positive psychotic experiences. PMID:27056622

Relative Contributions of Specific Activity Histories and Spontaneous Processes to Size Remodeling of Glutamatergic Synapses

PubMed Central

Dvorkin, Roman; Ziv, Noam E.

2016-01-01

The idea that synaptic properties are defined by specific pre- and postsynaptic activity histories is one of the oldest and most influential tenets of contemporary neuroscience. Recent studies also indicate, however, that synaptic properties often change spontaneously, even in the absence of specific activity patterns or any activity whatsoever. What, then, are the relative contributions of activity history-dependent and activity history-independent processes to changes synapses undergo? To compare the relative contributions of these processes, we imaged, in spontaneously active networks of cortical neurons, glutamatergic synapses formed between the same axons and neurons or dendrites under the assumption that their similar activity histories should result in similar size changes over timescales of days. The size covariance of such commonly innervated (CI) synapses was then compared to that of synapses formed by different axons (non-CI synapses) that differed in their activity histories. We found that the size covariance of CI synapses was greater than that of non-CI synapses; yet overall size covariance of CI synapses was rather modest. Moreover, momentary and time-averaged sizes of CI synapses correlated rather poorly, in perfect agreement with published electron microscopy-based measurements of mouse cortex synapses. A conservative estimate suggested that ~40% of the observed size remodeling was attributable to specific activity histories, whereas ~10% and ~50% were attributable to cell-wide and spontaneous, synapse-autonomous processes, respectively. These findings demonstrate that histories of naturally occurring activity patterns can direct glutamatergic synapse remodeling but also suggest that the contributions of spontaneous, possibly stochastic, processes are at least as great. PMID:27776122

Sample Size Calculations for Population Size Estimation Studies Using Multiplier Methods With Respondent-Driven Sampling Surveys.

PubMed

Fearon, Elizabeth; Chabata, Sungai T; Thompson, Jennifer A; Cowan, Frances M; Hargreaves, James R

2017-09-14

While guidance exists for obtaining population size estimates using multiplier methods with respondent-driven sampling surveys, we lack specific guidance for making sample size decisions. To guide the design of multiplier method population size estimation studies using respondent-driven sampling surveys to reduce the random error around the estimate obtained. The population size estimate is obtained by dividing the number of individuals receiving a service or the number of unique objects distributed (M) by the proportion of individuals in a representative survey who report receipt of the service or object (P). We have developed an approach to sample size calculation, interpreting methods to estimate the variance around estimates obtained using multiplier methods in conjunction with research into design effects and respondent-driven sampling. We describe an application to estimate the number of female sex workers in Harare, Zimbabwe. There is high variance in estimates. Random error around the size estimate reflects uncertainty from M and P, particularly when the estimate of P in the respondent-driven sampling survey is low. As expected, sample size requirements are higher when the design effect of the survey is assumed to be greater. We suggest a method for investigating the effects of sample size on the precision of a population size estimate obtained using multipler methods and respondent-driven sampling. Uncertainty in the size estimate is high, particularly when P is small, so balancing against other potential sources of bias, we advise researchers to consider longer service attendance reference periods and to distribute more unique objects, which is likely to result in a higher estimate of P in the respondent-driven sampling survey. ©Elizabeth Fearon, Sungai T Chabata, Jennifer A Thompson, Frances M Cowan, James R Hargreaves. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 14.09.2017.

Relative efficiency and sample size for cluster randomized trials with variable cluster sizes.

PubMed

You, Zhiying; Williams, O Dale; Aban, Inmaculada; Kabagambe, Edmond Kato; Tiwari, Hemant K; Cutter, Gary

2011-02-01

The statistical power of cluster randomized trials depends on two sample size components, the number of clusters per group and the numbers of individuals within clusters (cluster size). Variable cluster sizes are common and this variation alone may have significant impact on study power. Previous approaches have taken this into account by either adjusting total sample size using a designated design effect or adjusting the number of clusters according to an assessment of the relative efficiency of unequal versus equal cluster sizes. This article defines a relative efficiency of unequal versus equal cluster sizes using noncentrality parameters, investigates properties of this measure, and proposes an approach for adjusting the required sample size accordingly. We focus on comparing two groups with normally distributed outcomes using t-test, and use the noncentrality parameter to define the relative efficiency of unequal versus equal cluster sizes and show that statistical power depends only on this parameter for a given number of clusters. We calculate the sample size required for an unequal cluster sizes trial to have the same power as one with equal cluster sizes. Relative efficiency based on the noncentrality parameter is straightforward to calculate and easy to interpret. It connects the required mean cluster size directly to the required sample size with equal cluster sizes. Consequently, our approach first determines the sample size requirements with equal cluster sizes for a pre-specified study power and then calculates the required mean cluster size while keeping the number of clusters unchanged. Our approach allows adjustment in mean cluster size alone or simultaneous adjustment in mean cluster size and number of clusters, and is a flexible alternative to and a useful complement to existing methods. Comparison indicated that we have defined a relative efficiency that is greater than the relative efficiency in the literature under some conditions. Our measure of relative efficiency might be less than the measure in the literature under some conditions, underestimating the relative efficiency. The relative efficiency of unequal versus equal cluster sizes defined using the noncentrality parameter suggests a sample size approach that is a flexible alternative and a useful complement to existing methods.

Risk-Based Sampling: I Don't Want to Weight in Vain.

PubMed

Powell, Mark R

2015-12-01

Recently, there has been considerable interest in developing risk-based sampling for food safety and animal and plant health for efficient allocation of inspection and surveillance resources. The problem of risk-based sampling allocation presents a challenge similar to financial portfolio analysis. Markowitz (1952) laid the foundation for modern portfolio theory based on mean-variance optimization. However, a persistent challenge in implementing portfolio optimization is the problem of estimation error, leading to false "optimal" portfolios and unstable asset weights. In some cases, portfolio diversification based on simple heuristics (e.g., equal allocation) has better out-of-sample performance than complex portfolio optimization methods due to estimation uncertainty. Even for portfolios with a modest number of assets, the estimation window required for true optimization may imply an implausibly long stationary period. The implications for risk-based sampling are illustrated by a simple simulation model of lot inspection for a small, heterogeneous group of producers. © 2015 Society for Risk Analysis.

Concentrations of selected constituents in surface-water and streambed-sediment samples collected from streams in and near an area of oil and natural-gas development, south-central Texas, 2011-13

USGS Publications Warehouse

Opsahl, Stephen P.; Crow, Cassi L.

2014-01-01

During collection of streambed-sediment samples, additional samples from a subset of three sites (the SAR Elmendorf, SAR 72, and SAR McFaddin sites) were processed by using a 63-µm sieve on one aliquot and a 2-mm sieve on a second aliquot for PAH and n-alkane analyses. The purpose of analyzing PAHs and n-alkanes on a sample containing sand, silt, and clay versus a sample containing only silt and clay was to provide data that could be used to determine if these organic constituents had a greater affinity for silt- and clay-sized particles relative to sand-sized particles. The greater concentrations of PAHs in the <63-μm size-fraction samples at all three of these sites are consistent with a greater percentage of binding sites associated with fine-grained (<63 μm) sediment versus coarse-grained (<2 mm) sediment. The larger difference in total PAHs between the <2-mm and <63-μm size-fraction samples at the SAR Elmendorf site might be related to the large percentage of sand in the <2-mm size-fraction sample which was absent in the <63-μm size-fraction sample. In contrast, the <2-mm size-fraction sample collected from the SAR McFaddin site contained very little sand and was similar in particle-size composition to the <63-μm size-fraction sample.

HYPERSAMP - HYPERGEOMETRIC ATTRIBUTE SAMPLING SYSTEM BASED ON RISK AND FRACTION DEFECTIVE

NASA Technical Reports Server (NTRS)

De, Salvo L. J.

1994-01-01

HYPERSAMP is a demonstration of an attribute sampling system developed to determine the minimum sample size required for any preselected value for consumer's risk and fraction of nonconforming. This statistical method can be used in place of MIL-STD-105E sampling plans when a minimum sample size is desirable, such as when tests are destructive or expensive. HYPERSAMP utilizes the Hypergeometric Distribution and can be used for any fraction nonconforming. The program employs an iterative technique that circumvents the obstacle presented by the factorial of a non-whole number. HYPERSAMP provides the required Hypergeometric sample size for any equivalent real number of nonconformances in the lot or batch under evaluation. Many currently used sampling systems, such as the MIL-STD-105E, utilize the Binomial or the Poisson equations as an estimate of the Hypergeometric when performing inspection by attributes. However, this is primarily because of the difficulty in calculation of the factorials required by the Hypergeometric. Sampling plans based on the Binomial or Poisson equations will result in the maximum sample size possible with the Hypergeometric. The difference in the sample sizes between the Poisson or Binomial and the Hypergeometric can be significant. For example, a lot size of 400 devices with an error rate of 1.0% and a confidence of 99% would require a sample size of 400 (all units would need to be inspected) for the Binomial sampling plan and only 273 for a Hypergeometric sampling plan. The Hypergeometric results in a savings of 127 units, a significant reduction in the required sample size. HYPERSAMP is a demonstration program and is limited to sampling plans with zero defectives in the sample (acceptance number of zero). Since it is only a demonstration program, the sample size determination is limited to sample sizes of 1500 or less. The Hypergeometric Attribute Sampling System demonstration code is a spreadsheet program written for IBM PC compatible computers running DOS and Lotus 1-2-3 or Quattro Pro. This program is distributed on a 5.25 inch 360K MS-DOS format diskette, and the program price includes documentation. This statistical method was developed in 1992.

Study samples are too small to produce sufficiently precise reliability coefficients.

PubMed

Charter, Richard A

2003-04-01

In a survey of journal articles, test manuals, and test critique books, the author found that a mean sample size (N) of 260 participants had been used for reliability studies on 742 tests. The distribution was skewed because the median sample size for the total sample was only 90. The median sample sizes for the internal consistency, retest, and interjudge reliabilities were 182, 64, and 36, respectively. The author presented sample size statistics for the various internal consistency methods and types of tests. In general, the author found that the sample sizes that were used in the internal consistency studies were too small to produce sufficiently precise reliability coefficients, which in turn could cause imprecise estimates of examinee true-score confidence intervals. The results also suggest that larger sample sizes have been used in the last decade compared with those that were used in earlier decades.

Analysis of Sample Size, Counting Time, and Plot Size from an Avian Point Count Survey on Hoosier National Forest, Indiana

Treesearch

Frank R. Thompson; Monica J. Schwalbach

1995-01-01

We report results of a point count survey of breeding birds on Hoosier National Forest in Indiana. We determined sample size requirements to detect differences in means and the effects of count duration and plot size on individual detection rates. Sample size requirements ranged from 100 to >1000 points with Type I and II error rates of <0.1 and 0.2. Sample...

Personality Assessment Inventory profiles of deployed combat troops: an empirical investigation of normative performance.

PubMed

Morey, Leslie C; Lowmaster, Sara E; Coldren, Rodney L; Kelly, Mark P; Parish, Robert V; Russell, Michael L

2011-06-01

The present study examined the normative scores and psychometric properties of the Personality Assessment Inventory (PAI; Morey, 1991) within a non-treatment-seeking sample of soldiers deployed to combat zones in Iraq, compared with a sample of community adults matched with respect to age and gender. Results indicate the scores and properties of the PAI scales were generally quite similar in the Iraq and community samples, with modest differences emerging on only 3 subscales addressing antisocial behavior, issues with close relationships, and interpersonal vigilance. These results suggest that standard normative interpretation of PAI scales is appropriate even when the instrument is administered in a combat zone. In comparison with prior research, the results may suggest that documented mental health issues among combat veterans, when present, may be particularly likely to emerge postdeployment. 2011 APA, all rights reserved

Microsatellite genotyping and genome-wide single nucleotide polymorphism-based indices of Plasmodium falciparum diversity within clinical infections.

PubMed

Murray, Lee; Mobegi, Victor A; Duffy, Craig W; Assefa, Samuel A; Kwiatkowski, Dominic P; Laman, Eugene; Loua, Kovana M; Conway, David J

2016-05-12

In regions where malaria is endemic, individuals are often infected with multiple distinct parasite genotypes, a situation that may impact on evolution of parasite virulence and drug resistance. Most approaches to studying genotypic diversity have involved analysis of a modest number of polymorphic loci, although whole genome sequencing enables a broader characterisation of samples. PCR-based microsatellite typing of a panel of ten loci was performed on Plasmodium falciparum in 95 clinical isolates from a highly endemic area in the Republic of Guinea, to characterize within-isolate genetic diversity. Separately, single nucleotide polymorphism (SNP) data from genome-wide short-read sequences of the same samples were used to derive within-isolate fixation indices (F ws), an inverse measure of diversity within each isolate compared to overall local genetic diversity. The latter indices were compared with the microsatellite results, and also with indices derived by randomly sampling modest numbers of SNPs. As expected, the number of microsatellite loci with more than one allele in each isolate was highly significantly inversely correlated with the genome-wide F ws fixation index (r = -0.88, P < 0.001). However, the microsatellite analysis revealed that most isolates contained mixed genotypes, even those that had no detectable genome sequence heterogeneity. Random sampling of different numbers of SNPs showed that an F ws index derived from ten or more SNPs with minor allele frequencies of >10 % had high correlation (r > 0.90) with the index derived using all SNPs. Different types of data give highly correlated indices of within-infection diversity, although PCR-based analysis detects low-level minority genotypes not apparent in bulk sequence analysis. When whole-genome data are not obtainable, quantitative assay of ten or more SNPs can yield a reasonably accurate estimate of the within-infection fixation index (F ws).

Loop propensity of the sequence YKGQP from staphylococcal nuclease: implications for the folding of nuclease.

PubMed

Patel, Sunita; Sasidhar, Yellamraju U

2007-10-01

Recently we performed molecular dynamics (MD) simulations on the folding of the hairpin peptide DTVKLMYKGQPMTFR from staphylococcal nuclease in explicit water. We found that the peptide folds into a hairpin conformation with native and nonnative hydrogen-bonding patterns. In all the folding events observed in the folding of the hairpin peptide, loop formation involving the region YKGQP was an important event. In order to trace the origins of the loop propensity of the sequence YKGQP, we performed MD simulations on the sequence starting from extended, polyproline II and native type I' turn conformations for a total simulation length of 300 ns, using the GROMOS96 force field under constant volume and temperature (NVT) conditions. The free-energy landscape of the peptide YKGQP shows minima corresponding to loop conformation with Tyr and Pro side-chain association, turn and extended conformational forms, with modest free-energy barriers separating the minima. To elucidate the role of Gly in facilitating loop formation, we also performed MD simulations of the mutated peptide YKAQP (Gly --> Ala mutation) under similar conditions starting from polyproline II conformation for 100 ns. Two minima corresponding to bend/turn and extended conformations were observed in the free-energy landscape for the peptide YKAQP. The free-energy barrier between the minima in the free-energy landscape of the peptide YKAQP was also modest. Loop conformation is largely sampled by the YKGQP peptide, while extended conformation is largely sampled by the YKAQP peptide. We also explain why the YKGQP sequence samples type II turn conformation in these simulations, whereas the sequence as part of the hairpin peptide DTVKLMYKGQPMTFR samples type I' turn conformation both in the X-ray crystal structure and in our earlier simulations on the folding of the hairpin peptide. We discuss the implications of our results to the folding of the staphylococcal nuclease. Copyright (c) 2007 European Peptide Society and John Wiley & Sons, Ltd.

Mapping cell populations in flow cytometry data for cross‐sample comparison using the Friedman–Rafsky test statistic as a distance measure

PubMed Central

Hsiao, Chiaowen; Liu, Mengya; Stanton, Rick; McGee, Monnie; Qian, Yu

2015-01-01

Abstract Flow cytometry (FCM) is a fluorescence‐based single‐cell experimental technology that is routinely applied in biomedical research for identifying cellular biomarkers of normal physiological responses and abnormal disease states. While many computational methods have been developed that focus on identifying cell populations in individual FCM samples, very few have addressed how the identified cell populations can be matched across samples for comparative analysis. This article presents FlowMap‐FR, a novel method for cell population mapping across FCM samples. FlowMap‐FR is based on the Friedman–Rafsky nonparametric test statistic (FR statistic), which quantifies the equivalence of multivariate distributions. As applied to FCM data by FlowMap‐FR, the FR statistic objectively quantifies the similarity between cell populations based on the shapes, sizes, and positions of fluorescence data distributions in the multidimensional feature space. To test and evaluate the performance of FlowMap‐FR, we simulated the kinds of biological and technical sample variations that are commonly observed in FCM data. The results show that FlowMap‐FR is able to effectively identify equivalent cell populations between samples under scenarios of proportion differences and modest position shifts. As a statistical test, FlowMap‐FR can be used to determine whether the expression of a cellular marker is statistically different between two cell populations, suggesting candidates for new cellular phenotypes by providing an objective statistical measure. In addition, FlowMap‐FR can indicate situations in which inappropriate splitting or merging of cell populations has occurred during gating procedures. We compared the FR statistic with the symmetric version of Kullback–Leibler divergence measure used in a previous population matching method with both simulated and real data. The FR statistic outperforms the symmetric version of KL‐distance in distinguishing equivalent from nonequivalent cell populations. FlowMap‐FR was also employed as a distance metric to match cell populations delineated by manual gating across 30 FCM samples from a benchmark FlowCAP data set. An F‐measure of 0.88 was obtained, indicating high precision and recall of the FR‐based population matching results. FlowMap‐FR has been implemented as a standalone R/Bioconductor package so that it can be easily incorporated into current FCM data analytical workflows. © 2015 International Society for Advancement of Cytometry PMID:26274018

Mapping cell populations in flow cytometry data for cross-sample comparison using the Friedman-Rafsky test statistic as a distance measure.

PubMed

Hsiao, Chiaowen; Liu, Mengya; Stanton, Rick; McGee, Monnie; Qian, Yu; Scheuermann, Richard H

2016-01-01

Flow cytometry (FCM) is a fluorescence-based single-cell experimental technology that is routinely applied in biomedical research for identifying cellular biomarkers of normal physiological responses and abnormal disease states. While many computational methods have been developed that focus on identifying cell populations in individual FCM samples, very few have addressed how the identified cell populations can be matched across samples for comparative analysis. This article presents FlowMap-FR, a novel method for cell population mapping across FCM samples. FlowMap-FR is based on the Friedman-Rafsky nonparametric test statistic (FR statistic), which quantifies the equivalence of multivariate distributions. As applied to FCM data by FlowMap-FR, the FR statistic objectively quantifies the similarity between cell populations based on the shapes, sizes, and positions of fluorescence data distributions in the multidimensional feature space. To test and evaluate the performance of FlowMap-FR, we simulated the kinds of biological and technical sample variations that are commonly observed in FCM data. The results show that FlowMap-FR is able to effectively identify equivalent cell populations between samples under scenarios of proportion differences and modest position shifts. As a statistical test, FlowMap-FR can be used to determine whether the expression of a cellular marker is statistically different between two cell populations, suggesting candidates for new cellular phenotypes by providing an objective statistical measure. In addition, FlowMap-FR can indicate situations in which inappropriate splitting or merging of cell populations has occurred during gating procedures. We compared the FR statistic with the symmetric version of Kullback-Leibler divergence measure used in a previous population matching method with both simulated and real data. The FR statistic outperforms the symmetric version of KL-distance in distinguishing equivalent from nonequivalent cell populations. FlowMap-FR was also employed as a distance metric to match cell populations delineated by manual gating across 30 FCM samples from a benchmark FlowCAP data set. An F-measure of 0.88 was obtained, indicating high precision and recall of the FR-based population matching results. FlowMap-FR has been implemented as a standalone R/Bioconductor package so that it can be easily incorporated into current FCM data analytical workflows. © The Authors. Published by Wiley Periodicals, Inc. on behalf of ISAC.

7 CFR 51.1406 - Sample for grade or size determination.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., AND STANDARDS) United States Standards for Grades of Pecans in the Shell 1 Sample for Grade Or Size Determination § 51.1406 Sample for grade or size determination. Each sample shall consist of 100 pecans. The...

The quality of the reported sample size calculations in randomized controlled trials indexed in PubMed.

PubMed

Lee, Paul H; Tse, Andy C Y

2017-05-01

There are limited data on the quality of reporting of information essential for replication of the calculation as well as the accuracy of the sample size calculation. We examine the current quality of reporting of the sample size calculation in randomized controlled trials (RCTs) published in PubMed and to examine the variation in reporting across study design, study characteristics, and journal impact factor. We also reviewed the targeted sample size reported in trial registries. We reviewed and analyzed all RCTs published in December 2014 with journals indexed in PubMed. The 2014 Impact Factors for the journals were used as proxies for their quality. Of the 451 analyzed papers, 58.1% reported an a priori sample size calculation. Nearly all papers provided the level of significance (97.7%) and desired power (96.6%), and most of the papers reported the minimum clinically important effect size (73.3%). The median (inter-quartile range) of the percentage difference of the reported and calculated sample size calculation was 0.0% (IQR -4.6%;3.0%). The accuracy of the reported sample size was better for studies published in journals that endorsed the CONSORT statement and journals with an impact factor. A total of 98 papers had provided targeted sample size on trial registries and about two-third of these papers (n=62) reported sample size calculation, but only 25 (40.3%) had no discrepancy with the reported number in the trial registries. The reporting of the sample size calculation in RCTs published in PubMed-indexed journals and trial registries were poor. The CONSORT statement should be more widely endorsed. Copyright © 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Proprioceptive Distance Cues Restore Perfect Size Constancy in Grasping, but Not Perception, When Vision Is Limited.

PubMed

Chen, Juan; Sperandio, Irene; Goodale, Melvyn Alan

2018-03-19

Our brain integrates information from multiple modalities in the control of behavior. When information from one sensory source is compromised, information from another source can compensate for the loss. What is not clear is whether the nature of this multisensory integration and the re-weighting of different sources of sensory information are the same across different control systems. Here, we investigated whether proprioceptive distance information (position sense of body parts) can compensate for the loss of visual distance cues that support size constancy in perception (mediated by the ventral visual stream) [1, 2] versus size constancy in grasping (mediated by the dorsal visual stream) [3-6], in which the real-world size of an object is computed despite changes in viewing distance. We found that there was perfect size constancy in both perception and grasping in a full-viewing condition (lights on, binocular viewing) and that size constancy in both tasks was dramatically disrupted in the restricted-viewing condition (lights off; monocular viewing of the same but luminescent object through a 1-mm pinhole). Importantly, in the restricted-viewing condition, proprioceptive cues about viewing distance originating from the non-grasping limb (experiment 1) or the inclination of the torso and/or the elbow angle of the grasping limb (experiment 2) compensated for the loss of visual distance cues to enable a complete restoration of size constancy in grasping but only a modest improvement of size constancy in perception. This suggests that the weighting of different sources of sensory information varies as a function of the control system being used. Copyright © 2018 Elsevier Ltd. All rights reserved.

Distribution of the two-sample t-test statistic following blinded sample size re-estimation.

PubMed

Lu, Kaifeng

2016-05-01

We consider the blinded sample size re-estimation based on the simple one-sample variance estimator at an interim analysis. We characterize the exact distribution of the standard two-sample t-test statistic at the final analysis. We describe a simulation algorithm for the evaluation of the probability of rejecting the null hypothesis at given treatment effect. We compare the blinded sample size re-estimation method with two unblinded methods with respect to the empirical type I error, the empirical power, and the empirical distribution of the standard deviation estimator and final sample size. We characterize the type I error inflation across the range of standardized non-inferiority margin for non-inferiority trials, and derive the adjusted significance level to ensure type I error control for given sample size of the internal pilot study. We show that the adjusted significance level increases as the sample size of the internal pilot study increases. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

ENHANCEMENT OF LEARNING ON SAMPLE SIZE CALCULATION WITH A SMARTPHONE APPLICATION: A CLUSTER-RANDOMIZED CONTROLLED TRIAL.

PubMed

Ngamjarus, Chetta; Chongsuvivatwong, Virasakdi; McNeil, Edward; Holling, Heinz

2017-01-01

Sample size determination usually is taught based on theory and is difficult to understand. Using a smartphone application to teach sample size calculation ought to be more attractive to students than using lectures only. This study compared levels of understanding of sample size calculations for research studies between participants attending a lecture only versus lecture combined with using a smartphone application to calculate sample sizes, to explore factors affecting level of post-test score after training sample size calculation, and to investigate participants’ attitude toward a sample size application. A cluster-randomized controlled trial involving a number of health institutes in Thailand was carried out from October 2014 to March 2015. A total of 673 professional participants were enrolled and randomly allocated to one of two groups, namely, 341 participants in 10 workshops to control group and 332 participants in 9 workshops to intervention group. Lectures on sample size calculation were given in the control group, while lectures using a smartphone application were supplied to the test group. Participants in the intervention group had better learning of sample size calculation (2.7 points out of maximnum 10 points, 95% CI: 24 - 2.9) than the participants in the control group (1.6 points, 95% CI: 1.4 - 1.8). Participants doing research projects had a higher post-test score than those who did not have a plan to conduct research projects (0.9 point, 95% CI: 0.5 - 1.4). The majority of the participants had a positive attitude towards the use of smartphone application for learning sample size calculation.

Evidentiary, extraevidentiary, and deliberation process predictors of real jury verdicts.

PubMed

Devine, Dennis J; Krouse, Paige C; Cavanaugh, Caitlin M; Basora, Jaime Colon

2016-12-01

In contrast to the extensive literature based on mock jurors, large-sample studies of decision making by real juries are relatively rare. In this field study, we examined relationships between jury verdicts and variables representing 3 classes of potential determinants-evidentiary, extraevidentiary, and deliberation process-using a sample of 114 criminal jury trials. Posttrial data were collected from 11 presiding judges, 31 attorneys, and 367 jurors using a Web-based questionnaire. The strength of the prosecution's evidence was strongly related to the occurrence of a conviction, whereas most extraevidentiary and deliberation process variables were only weakly to modestly related in bivariate form and when the prosecution's evidence strength was controlled. Notable exceptions to this pattern were jury demographic diversity as represented by the number of different race-gender subgroups (e.g., Black males) present in the jury, and several deliberation process variables reflecting advocacy for acquittal (e.g., presence of an identifiable proacquittal faction within the jury and proacquittal advocacy by the foreperson). Variables reflecting advocacy for conviction were essentially unrelated to jury verdict. Sets of extraevidentiary and deliberation variables were each able to modestly improve the explanation of jury verdicts over prosecution evidence strength in multivariate models. This study highlights the predictive efficacy of prosecution evidence strength with respect to jury verdicts, as well as the potential importance of jury demographic diversity and advocacy for acquittal during deliberation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Physical-depth architectural requirements for generating universal photonic cluster states

NASA Astrophysics Data System (ADS)

Morley-Short, Sam; Bartolucci, Sara; Gimeno-Segovia, Mercedes; Shadbolt, Pete; Cable, Hugo; Rudolph, Terry

2018-01-01

Most leading proposals for linear-optical quantum computing (LOQC) use cluster states, which act as a universal resource for measurement-based (one-way) quantum computation. In ballistic approaches to LOQC, cluster states are generated passively from small entangled resource states using so-called fusion operations. Results from percolation theory have previously been used to argue that universal cluster states can be generated in the ballistic approach using schemes which exceed the critical threshold for percolation, but these results consider cluster states with unbounded size. Here we consider how successful percolation can be maintained using a physical architecture with fixed physical depth, assuming that the cluster state is continuously generated and measured, and therefore that only a finite portion of it is visible at any one point in time. We show that universal LOQC can be implemented using a constant-size device with modest physical depth, and that percolation can be exploited using simple pathfinding strategies without the need for high-complexity algorithms.

Accurate Modeling of X-ray Extinction by Interstellar Grains

NASA Astrophysics Data System (ADS)

Hoffman, John; Draine, B. T.

2016-02-01

Interstellar abundance determinations from fits to X-ray absorption edges often rely on the incorrect assumption that scattering is insignificant and can be ignored. We show instead that scattering contributes significantly to the attenuation of X-rays for realistic dust grain size distributions and substantially modifies the spectrum near absorption edges of elements present in grains. The dust attenuation modules used in major X-ray spectral fitting programs do not take this into account. We show that the consequences of neglecting scattering on the determination of interstellar elemental abundances are modest; however, scattering (along with uncertainties in the grain size distribution) must be taken into account when near-edge extinction fine structure is used to infer dust mineralogy. We advertise the benefits and accuracy of anomalous diffraction theory for both X-ray halo analysis and near edge absorption studies. We present an open source Fortran suite, General Geometry Anomalous Diffraction Theory (GGADT), that calculates X-ray absorption, scattering, and differential scattering cross sections for grains of arbitrary geometry and composition.

The void spectrum in two-dimensional numerical simulations of gravitational clustering

NASA Technical Reports Server (NTRS)

Kauffmann, Guinevere; Melott, Adrian L.

1992-01-01

An algorithm for deriving a spectrum of void sizes from two-dimensional high-resolution numerical simulations of gravitational clustering is tested, and it is verified that it produces the correct results where those results can be anticipated. The method is used to study the growth of voids as clustering proceeds. It is found that the most stable indicator of the characteristic void 'size' in the simulations is the mean fractional area covered by voids of diameter d, in a density field smoothed at its correlation length. Very accurate scaling behavior is found in power-law numerical models as they evolve. Eventually, this scaling breaks down as the nonlinearity reaches larger scales. It is shown that this breakdown is a manifestation of the undesirable effect of boundary conditions on simulations, even with the very large dynamic range possible here. A simple criterion is suggested for deciding when simulations with modest large-scale power may systematically underestimate the frequency of larger voids.

Preliminary Sizing Study of Ares-I and Ares-V Liquid Hydrogen Tanks

NASA Technical Reports Server (NTRS)

Oliver, Stanley T.; Harper, David W.

2012-01-01

A preliminary sizing study of two cryogenic propellant tanks was performed using a FORTRAN optimization program to determine weight efficient orthogrid designs for the tank barrels sections only. Various tensile and compressive failure modes were considered, including general buckling of cylinders with a shell buckling knockdown factor. Eight independent combinations of three design requirements were also considered and their effects on the tanks weight. The approach was to investigate each design case with a variable shell buckling knockdown factor, determining the most weight efficient combination of orthogrid design parameters. Numerous optimization analyses were performed, and the results presented herein compare the effects of the different design requirements and shell buckling knockdown factor. Through a series of comparisons between design requirements or shell buckling knockdown factors, the relative change in overall tank barrel weights is shown. The findings indicate that the design requirements can substantually increase the tank weight while a less conservative shell buckling knockdown factor can modestly reduce the tank weight.

Thermodynamics of quasideterministic digital computers

NASA Astrophysics Data System (ADS)

Chu, Dominique

2018-02-01

A central result of stochastic thermodynamics is that irreversible state transitions of Markovian systems entail a cost in terms of an infinite entropy production. A corollary of this is that strictly deterministic computation is not possible. Using a thermodynamically consistent model, we show that quasideterministic computation can be achieved at finite, and indeed modest cost with accuracies that are indistinguishable from deterministic behavior for all practical purposes. Concretely, we consider the entropy production of stochastic (Markovian) systems that behave like and and a not gates. Combinations of these gates can implement any logical function. We require that these gates return the correct result with a probability that is very close to 1, and additionally, that they do so within finite time. The central component of the model is a machine that can read and write binary tapes. We find that the error probability of the computation of these gates falls with the power of the system size, whereas the cost only increases linearly with the system size.

Effects of Childhood and Middle-Adulthood Family Conditions on Later-Life Mortality: Evidence from the Utah Population Database, 1850-2002

PubMed Central

Mineau, Mineau P; Gilda, Garibotti; Kerber, Richard

2014-01-01

We examine how key early family circumstances affect mortality risks decades later. Early life conditions are measured by parental mortality, parental fertility (e.g., offspring sibship size, parental age at offspring birth), religious upbringing, and parental socioeconomic status. Prior to these early life conditions are familial and genetic factors that affect life-span. Accordingly, we consider the role of parental and familial longevity on adult mortality risks. We analyze the large Utah Population Database which contains a vast amount of genealogical and other vital/health data that contain full life histories of individuals and hundreds of their relatives. To control for unobserved heterogeneity, we analyze sib-pair data for 12,000 sib-pairs using frailty models. We found modest effects of key childhood conditions (birth order, sibship size, parental religiosity, parental SES, and parental death in childhood). Our measures of familial aggregation of longevity were large and suggest an alternative view of early life conditions. PMID:19278766

Developing the Noncentrality Parameter for Calculating Group Sample Sizes in Heterogeneous Analysis of Variance

ERIC Educational Resources Information Center

Luh, Wei-Ming; Guo, Jiin-Huarng

2011-01-01

Sample size determination is an important issue in planning research. In the context of one-way fixed-effect analysis of variance, the conventional sample size formula cannot be applied for the heterogeneous variance cases. This study discusses the sample size requirement for the Welch test in the one-way fixed-effect analysis of variance with…

Sample Size Determination for Regression Models Using Monte Carlo Methods in R

ERIC Educational Resources Information Center

Beaujean, A. Alexander

2014-01-01

A common question asked by researchers using regression models is, What sample size is needed for my study? While there are formulae to estimate sample sizes, their assumptions are often not met in the collected data. A more realistic approach to sample size determination requires more information such as the model of interest, strength of the…

Nomogram for sample size calculation on a straightforward basis for the kappa statistic.

PubMed

Hong, Hyunsook; Choi, Yunhee; Hahn, Seokyung; Park, Sue Kyung; Park, Byung-Joo

2014-09-01

Kappa is a widely used measure of agreement. However, it may not be straightforward in some situation such as sample size calculation due to the kappa paradox: high agreement but low kappa. Hence, it seems reasonable in sample size calculation that the level of agreement under a certain marginal prevalence is considered in terms of a simple proportion of agreement rather than a kappa value. Therefore, sample size formulae and nomograms using a simple proportion of agreement rather than a kappa under certain marginal prevalences are proposed. A sample size formula was derived using the kappa statistic under the common correlation model and goodness-of-fit statistic. The nomogram for the sample size formula was developed using SAS 9.3. The sample size formulae using a simple proportion of agreement instead of a kappa statistic and nomograms to eliminate the inconvenience of using a mathematical formula were produced. A nomogram for sample size calculation with a simple proportion of agreement should be useful in the planning stages when the focus of interest is on testing the hypothesis of interobserver agreement involving two raters and nominal outcome measures. Copyright © 2014 Elsevier Inc. All rights reserved.

Simulation of reaction diffusion processes over biologically relevant size and time scales using multi-GPU workstations

PubMed Central

Hallock, Michael J.; Stone, John E.; Roberts, Elijah; Fry, Corey; Luthey-Schulten, Zaida

2014-01-01

Simulation of in vivo cellular processes with the reaction-diffusion master equation (RDME) is a computationally expensive task. Our previous software enabled simulation of inhomogeneous biochemical systems for small bacteria over long time scales using the MPD-RDME method on a single GPU. Simulations of larger eukaryotic systems exceed the on-board memory capacity of individual GPUs, and long time simulations of modest-sized cells such as yeast are impractical on a single GPU. We present a new multi-GPU parallel implementation of the MPD-RDME method based on a spatial decomposition approach that supports dynamic load balancing for workstations containing GPUs of varying performance and memory capacity. We take advantage of high-performance features of CUDA for peer-to-peer GPU memory transfers and evaluate the performance of our algorithms on state-of-the-art GPU devices. We present parallel e ciency and performance results for simulations using multiple GPUs as system size, particle counts, and number of reactions grow. We also demonstrate multi-GPU performance in simulations of the Min protein system in E. coli. Moreover, our multi-GPU decomposition and load balancing approach can be generalized to other lattice-based problems. PMID:24882911

The effect of matrix microstructure on cyclic response and fatigue behavior of particle- reinforced 2219 aluminum: Part I. room temperature behavior

NASA Astrophysics Data System (ADS)

Vyletel, G. M.; Allison, J. E.; van Aken, D. C.

1995-12-01

The low-cycle and high-cycle fatigue behavior and cyclic response of naturally aged and overaged 2219/TiC/15p and unreinforced 2219 Al were investigated using plastic strain-controlled and stress-controlled testing. In addition, the influence of grain size on the particle-reinforced materials was examined. In both reinforced and unreinforced materials, the naturally aged conditions were cyclically unstable, exhibiting an initial hardening behavior followed by an extended region of cyclic stability and ultimately a softening region. The overaged reinforced material was cyclically stable for the plastic strains examined, while the overaged unreinforced material exhibited cyclic hardening at plastic strains greater than 2.5 × 10-4. Decreasing grain size of particle-reinforced materials modestly increased the cyclic flow stress of both naturally aged and overaged materials. Reinforced and unreinforced materials exhibited similar fatigue life behaviors; however, the reinforced and unreinforced naturally aged materials had superior fatigue lives in comparison to the overaged materials. Grain size had no effect on the fatigue life behavior of the particle-reinforced materials. The fatigue lives were strongly influenced by the presence of clusters of TiC particles and exogenous Al3Ti intermetallics.

Simulation of reaction diffusion processes over biologically relevant size and time scales using multi-GPU workstations.

PubMed

Hallock, Michael J; Stone, John E; Roberts, Elijah; Fry, Corey; Luthey-Schulten, Zaida

2014-05-01

Simulation of in vivo cellular processes with the reaction-diffusion master equation (RDME) is a computationally expensive task. Our previous software enabled simulation of inhomogeneous biochemical systems for small bacteria over long time scales using the MPD-RDME method on a single GPU. Simulations of larger eukaryotic systems exceed the on-board memory capacity of individual GPUs, and long time simulations of modest-sized cells such as yeast are impractical on a single GPU. We present a new multi-GPU parallel implementation of the MPD-RDME method based on a spatial decomposition approach that supports dynamic load balancing for workstations containing GPUs of varying performance and memory capacity. We take advantage of high-performance features of CUDA for peer-to-peer GPU memory transfers and evaluate the performance of our algorithms on state-of-the-art GPU devices. We present parallel e ciency and performance results for simulations using multiple GPUs as system size, particle counts, and number of reactions grow. We also demonstrate multi-GPU performance in simulations of the Min protein system in E. coli . Moreover, our multi-GPU decomposition and load balancing approach can be generalized to other lattice-based problems.

Replacement of the Faces subtest by Visual Reproductions within Wechsler Memory Scale-Third Edition (WMS-III) visual memory indexes: implications for discrepancy analysis.

PubMed

Hawkins, Keith A; Tulsky, David S

2004-06-01

Within discrepancy analysis differences between scores are examined for abnormality. Although larger differences are generally associated with rising impairment probabilities, the relationship between discrepancy size and abnormality varies across score pairs in relation to the correlation between the contrasted scores in normal subjects. Examinee ability level also affects the size of discrepancies observed normally. Wechsler Memory Scale-Third Edition (WMS-III) visual index scores correlate only modestly with other Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) and WMS-III index scores; consequently, differences between these scores and others have to be very large before they become unusual, especially for subjects of higher intelligence. The substitution of the Faces subtest by Visual Reproductions within visual memory indexes formed by the combination of WMS-III visual subtests (creating immediate recall, delayed recall, and combined immediate and delayed index scores) results in higher correlation coefficients, and a decline in the discrepancy size required to surpass base rate thresholds for probable impairment. This gain appears not to occur at the cost of a diminished sensitivity to diverse pathologies. New WMS-III discrepancy base rate data are supplied to complement those currently available to clinicians.

R&D policy, agency costs and innovation in personalized medicine.

PubMed

Yin, Wesley

2009-09-01

The Orphan Drug Act (ODA) was designed to spur the development of drugs for rare diseases. In principle, its design also incentivizes pharmaceutical firms to develop drugs for "rare" subdivisions of more prevalent diseases. I find that in response to this incentive, firms develop drugs for ODA-qualifying subdivisions of non-rare diseases. The impact in these tailored drug markets represents half of the total R&D response to the ODA. I also find that 10-percent of the innovation in subdivided disease drugs induced by the ODA would have been conducted without the policy. While modest in size, this inefficiency suggests that agency problems should be considered when designing innovation policy.

Parallel implementation of Hartree-Fock and density functional theory analytical second derivatives

NASA Astrophysics Data System (ADS)

Baker, Jon; Wolinski, Krzysztof; Malagoli, Massimo; Pulay, Peter

2004-01-01

We present an efficient, parallel implementation for the calculation of Hartree-Fock and density functional theory analytical Hessian (force constant, nuclear second derivative) matrices. These are important for the determination of harmonic vibrational frequencies, and to classify stationary points on potential energy surfaces. Our program is designed for modest parallelism (4-16 CPUs) as exemplified by our standard eight-processor QuantumCube™. We can routinely handle systems with up to 100+ atoms and 1000+ basis functions using under 0.5 GB of RAM memory per CPU. Timings are presented for several systems, ranging in size from aspirin (C9H8O4) to nickel octaethylporphyrin (C36H44N4Ni).

U.S. aerospace industry opinion of the effect of computer-aided prediction-design technology on future wind-tunnel test requirements for aircraft development programs

NASA Technical Reports Server (NTRS)

Treon, S. L.

1979-01-01

A survey of the U.S. aerospace industry in late 1977 suggests that there will be an increasing use of computer-aided prediction-design technology (CPD Tech) in the aircraft development process but that, overall, only a modest reduction in wind-tunnel test requirements from the current level is expected in the period through 1995. Opinions were received from key spokesmen in 23 of the 26 solicited major companies or corporate divisions involved in the design and manufacture of nonrotary wing aircraft. Development programs for nine types of aircraft related to test phases and wind-tunnel size and speed range were considered.

Reconsidering community-based health promotion: promise, performance, and potential.

PubMed

Merzel, Cheryl; D'Afflitti, Joanna

2003-04-01

Contemporary public health emphasizes a community-based approach to health promotion and disease prevention. The evidence from the past 20 years indicates, however, that many community-based programs have had only modest impact, with the notable exception of a number of HIV prevention programs. To better understand the reasons for these outcomes, we conducted a systematic literature review of 32 community-based prevention programs. Reasons for poor performance include methodological challenges to study design and evaluation, concurrent secular trends, smaller-than-expected effect sizes, limitations of the interventions, and limitations of theories used. The effectiveness of HIV programs appears to be related in part to extensive formative research and an emphasis on changing social norms.

Sample size calculation in cost-effectiveness cluster randomized trials: optimal and maximin approaches.

PubMed

Manju, Md Abu; Candel, Math J J M; Berger, Martijn P F

2014-07-10

In this paper, the optimal sample sizes at the cluster and person levels for each of two treatment arms are obtained for cluster randomized trials where the cost-effectiveness of treatments on a continuous scale is studied. The optimal sample sizes maximize the efficiency or power for a given budget or minimize the budget for a given efficiency or power. Optimal sample sizes require information on the intra-cluster correlations (ICCs) for effects and costs, the correlations between costs and effects at individual and cluster levels, the ratio of the variance of effects translated into costs to the variance of the costs (the variance ratio), sampling and measuring costs, and the budget. When planning, a study information on the model parameters usually is not available. To overcome this local optimality problem, the current paper also presents maximin sample sizes. The maximin sample sizes turn out to be rather robust against misspecifying the correlation between costs and effects at the cluster and individual levels but may lose much efficiency when misspecifying the variance ratio. The robustness of the maximin sample sizes against misspecifying the ICCs depends on the variance ratio. The maximin sample sizes are robust under misspecification of the ICC for costs for realistic values of the variance ratio greater than one but not robust under misspecification of the ICC for effects. Finally, we show how to calculate optimal or maximin sample sizes that yield sufficient power for a test on the cost-effectiveness of an intervention.

Sample size determination in group-sequential clinical trials with two co-primary endpoints

PubMed Central

Asakura, Koko; Hamasaki, Toshimitsu; Sugimoto, Tomoyuki; Hayashi, Kenichi; Evans, Scott R; Sozu, Takashi

2014-01-01

We discuss sample size determination in group-sequential designs with two endpoints as co-primary. We derive the power and sample size within two decision-making frameworks. One is to claim the test intervention’s benefit relative to control when superiority is achieved for the two endpoints at the same interim timepoint of the trial. The other is when the superiority is achieved for the two endpoints at any interim timepoint, not necessarily simultaneously. We evaluate the behaviors of sample size and power with varying design elements and provide a real example to illustrate the proposed sample size methods. In addition, we discuss sample size recalculation based on observed data and evaluate the impact on the power and Type I error rate. PMID:24676799

Approximate sample size formulas for the two-sample trimmed mean test with unequal variances.

PubMed

Luh, Wei-Ming; Guo, Jiin-Huarng

2007-05-01

Yuen's two-sample trimmed mean test statistic is one of the most robust methods to apply when variances are heterogeneous. The present study develops formulas for the sample size required for the test. The formulas are applicable for the cases of unequal variances, non-normality and unequal sample sizes. Given the specified alpha and the power (1-beta), the minimum sample size needed by the proposed formulas under various conditions is less than is given by the conventional formulas. Moreover, given a specified size of sample calculated by the proposed formulas, simulation results show that Yuen's test can achieve statistical power which is generally superior to that of the approximate t test. A numerical example is provided.

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

Jomekian, A.; Faculty of Chemical Engineering, Iran University of Science and Technology; Behbahani, R.M., E-mail: behbahani@put.ac.ir

Ultra porous ZIF-8 particles synthesized using PEO/PA6 based poly(ether-block-amide) (Pebax 1657) as structure directing agent. Structural properties of ZIF-8 samples prepared under different synthesis parameters were investigated by laser particle size analysis, XRD, N{sub 2} adsorption analysis, BJH and BET tests. The overall results showed that: (1) The mean pore size of all ZIF-8 samples increased remarkably (from 0.34 nm to 1.1–2.5 nm) compared to conventionally synthesized ZIF-8 samples. (2) Exceptional BET surface area of 1869 m{sup 2}/g was obtained for a ZIF-8 sample with mean pore size of 2.5 nm. (3) Applying high concentrations of Pebax 1657 to themore » synthesis solution lead to higher surface area, larger pore size and smaller particle size for ZIF-8 samples. (4) Both, Increase in temperature and decrease in molar ratio of MeIM/Zn{sup 2+} had increasing effect on ZIF-8 particle size, pore size, pore volume, crystallinity and BET surface area of all investigated samples. - Highlights: • The pore size of ZIF-8 samples synthesized with Pebax 1657 increased remarkably. • The BET surface area of 1869 m{sup 2}/gr obtained for a ZIF-8 synthesized sample with Pebax. • Increase in temperature had increasing effect on textural properties of ZIF-8 samples. • Decrease in MeIM/Zn{sup 2+} had increasing effect on textural properties of ZIF-8 samples.« less

Effects of Calibration Sample Size and Item Bank Size on Ability Estimation in Computerized Adaptive Testing

ERIC Educational Resources Information Center

Sahin, Alper; Weiss, David J.

2015-01-01

This study aimed to investigate the effects of calibration sample size and item bank size on examinee ability estimation in computerized adaptive testing (CAT). For this purpose, a 500-item bank pre-calibrated using the three-parameter logistic model with 10,000 examinees was simulated. Calibration samples of varying sizes (150, 250, 350, 500,…

Sample size calculations for case-control studies

Cancer.gov

This R package can be used to calculate the required samples size for unconditional multivariate analyses of unmatched case-control studies. The sample sizes are for a scalar exposure effect, such as binary, ordinal or continuous exposures. The sample sizes can also be computed for scalar interaction effects. The analyses account for the effects of potential confounder variables that are also included in the multivariate logistic model.

Efficient Screening of Climate Model Sensitivity to a Large Number of Perturbed Input Parameters [plus supporting information

DOE PAGES

Covey, Curt; Lucas, Donald D.; Tannahill, John; ...

2013-07-01

Modern climate models contain numerous input parameters, each with a range of possible values. Since the volume of parameter space increases exponentially with the number of parameters N, it is generally impossible to directly evaluate a model throughout this space even if just 2-3 values are chosen for each parameter. Sensitivity screening algorithms, however, can identify input parameters having relatively little effect on a variety of output fields, either individually or in nonlinear combination.This can aid both model development and the uncertainty quantification (UQ) process. Here we report results from a parameter sensitivity screening algorithm hitherto untested in climate modeling,more » the Morris one-at-a-time (MOAT) method. This algorithm drastically reduces the computational cost of estimating sensitivities in a high dimensional parameter space because the sample size grows linearly rather than exponentially with N. It nevertheless samples over much of the N-dimensional volume and allows assessment of parameter interactions, unlike traditional elementary one-at-a-time (EOAT) parameter variation. We applied both EOAT and MOAT to the Community Atmosphere Model (CAM), assessing CAM’s behavior as a function of 27 uncertain input parameters related to the boundary layer, clouds, and other subgrid scale processes. For radiation balance at the top of the atmosphere, EOAT and MOAT rank most input parameters similarly, but MOAT identifies a sensitivity that EOAT underplays for two convection parameters that operate nonlinearly in the model. MOAT’s ranking of input parameters is robust to modest algorithmic variations, and it is qualitatively consistent with model development experience. Supporting information is also provided at the end of the full text of the article.« less

Size and myonuclear domains in Rhesus soleus muscle fibers: short-term spaceflight

NASA Technical Reports Server (NTRS)

Roy, R. R.; Zhong, H.; Talmadge, R. J.; Bodine, S. C.; Fanton, J. W.; Koslovskaya, I.; Edgerton, V. R.

2001-01-01

The cross-sectional area (CSA), myonuclear number per mm of fiber length, and myonuclear domain (cytoplasmic volume/myonucleus) of mechanically isolated single fibers from biopsies of the soleus muscle of 5 vivarium control, 3 flight simulation and 2 flight (BION 11) Rhesus monkeys (Macaca [correction of Macacca] mulatta) were determined using confocal microscopy before and after a 14-day experimental period. Simulation monkeys were confined in chairs placed in capsules identical to those used during the flight. Fibers were classified as type I, type II or hybrid (containing both types I and II) based on myosin heavy chain (MHC) gel electrophoresis. A majority of the fibers sampled contained only type I MHC, i.e. 89, 62 and 68% for the control, simulation and flight groups, respectively. Most of the remaining fibers were hybrids, i.e. 8, 36 and 32% for the same groups. There were no significant pre-post differences in the fiber type composition for any of the experimental groups. There also were no significant pre-post differences in fiber CSA, myonuclear number or myonuclear domain. There was, however, a tendency for the fibers in the post-flight biopsies to have a smaller mean CSA and myonuclear domain (approximately 10%, p=0.07) than the fibers in the pre-flight biopsy. The combined mean cytoplasmic volume/myonucleus for all muscle fiber phenotypes in the Rhesus soleus muscle was approximately 25,000 micrometers3 and there were no differences in pre-post samples for the control and simulated groups. The cytoplasmic domains tended to be lower (p=0.08) after than before flight. No phenotype differences in cytoplasmic domains were observed. These data suggest that after a relatively short period of actual spaceflight, modest fiber atrophy occurs in the soleus muscle fibers without a concomitant change in myonuclear number.

The interpersonal theory of suicide: A systematic review and meta-analysis of a decade of cross-national research.

PubMed

Chu, Carol; Buchman-Schmitt, Jennifer M; Stanley, Ian H; Hom, Melanie A; Tucker, Raymond P; Hagan, Christopher R; Rogers, Megan L; Podlogar, Matthew C; Chiurliza, Bruno; Ringer, Fallon B; Michaels, Matthew S; Patros, Connor H G; Joiner, Thomas E

2017-12-01

Over the past decade, the interpersonal theory of suicide has contributed to substantial advances in the scientific and clinical understanding of suicide and related conditions. The interpersonal theory of suicide posits that suicidal desire emerges when individuals experience intractable feelings of perceived burdensomeness and thwarted belongingness and near-lethal or lethal suicidal behavior occurs in the presence of suicidal desire and capability for suicide. A growing number of studies have tested these posited pathways in various samples; however, these findings have yet to be evaluated meta-analytically. This paper aimed to (a) conduct a systematic review of the unpublished and published, peer-reviewed literature examining the relationship between interpersonal theory constructs and suicidal thoughts and behaviors, (b) conduct meta-analyses testing the interpersonal theory hypotheses, and (c) evaluate the influence of various moderators on these relationships. Four electronic bibliographic databases were searched through the end of March, 2016: PubMed, Medline, PsycINFO, and Web of Science. Hypothesis-driven meta-analyses using random effects models were conducted using 122 distinct unpublished and published samples. Findings supported the interpersonal theory: the interaction between thwarted belongingness and perceived burdensomeness was significantly associated with suicidal ideation; and the interaction between thwarted belongingness, perceived burdensomeness, and capability for suicide was significantly related to a greater number of prior suicide attempts. However, effect sizes for these interactions were modest. Alternative configurations of theory variables were similarly useful for predicting suicide risk as theory-consistent pathways. We conclude with limitations and recommendations for the interpersonal theory as a framework for understanding the suicidal spectrum. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Development of genomic tools in a widespread tropical tree, Symphonia globulifera L.f.: a new low-coverage draft genome, SNP and SSR markers.

PubMed

Olsson, Sanna; Seoane-Zonjic, Pedro; Bautista, Rocío; Claros, M Gonzalo; González-Martínez, Santiago C; Scotti, Ivan; Scotti-Saintagne, Caroline; Hardy, Olivier J; Heuertz, Myriam

2017-07-01

Population genetic studies in tropical plants are often challenging because of limited information on taxonomy, phylogenetic relationships and distribution ranges, scarce genomic information and logistic challenges in sampling. We describe a strategy to develop robust and widely applicable genetic markers based on a modest development of genomic resources in the ancient tropical tree species Symphonia globulifera L.f. (Clusiaceae), a keystone species in African and Neotropical rainforests. We provide the first low-coverage (11X) fragmented draft genome sequenced on an individual from Cameroon, covering 1.027 Gbp or 67.5% of the estimated genome size. Annotation of 565 scaffolds (7.57 Mbp) resulted in the prediction of 1046 putative genes (231 of them containing a complete open reading frame) and 1523 exact simple sequence repeats (SSRs, microsatellites). Aligning a published transcriptome of a French Guiana population against this draft genome produced 923 high-quality single nucleotide polymorphisms. We also preselected genic SSRs in silico that were conserved and polymorphic across a wide geographical range, thus reducing marker development tests on rare DNA samples. Of 23 SSRs tested, 19 amplified and 18 were successfully genotyped in four S. globulifera populations from South America (Brazil and French Guiana) and Africa (Cameroon and São Tomé island, F ST  = 0.34). Most loci showed only population-specific deviations from Hardy-Weinberg proportions, pointing to local population effects (e.g. null alleles). The described genomic resources are valuable for evolutionary studies in Symphonia and for comparative studies in plants. The methods are especially interesting for widespread tropical or endangered taxa with limited DNA availability. © 2016 John Wiley & Sons Ltd.

Longitudinal assessment of local and global functional connectivity following sports-related concussion.

PubMed

Meier, Timothy B; Bellgowan, Patrick S F; Mayer, Andrew R

2017-02-01

Growing evidence suggests that sports-related concussions (SRC) may lead to acute changes in intrinsic functional connectivity, although most studies to date have been cross-sectional in nature with relatively modest sample sizes. We longitudinally assessed changes in local and global resting state functional connectivity using metrics that do not require a priori seed or network selection (regional homogeneity; ReHo and global brain connectivity; GBC, respectively). A large sample of collegiate athletes (N = 43) was assessed approximately one day (1.74 days post-injury, N = 34), one week (8.44 days, N = 34), and one month post-concussion (32.47 days, N = 30). Healthy contact sport-athletes served as controls (N = 51). Concussed athletes showed improvement in mood symptoms at each time point (p's < 0.05), but had significantly higher mood scores than healthy athletes at every time point (p's < 0.05). In contrast, self-reported symptoms and cognitive deficits improved over time following concussion (p's < 0.001), returning to healthy levels by one week post-concussion. ReHo in sensorimotor, visual, and temporal cortices increased over time post-concussion, and was greatest at one month post-injury. Conversely, ReHo in the frontal cortex decreased over time following SRC, with the greatest decrease evident at one month post-concussion. Differences in ReHo relative to healthy athletes were primarily observed at one month post-concussion rather than the more acute time points. Contrary to our hypothesis, no significant cross-sectional or longitudinal differences in GBC were observed. These results are suggestive of a delayed onset of local connectivity changes following SRC.

Lithium Inventory of 2 Solar Mass Red Clump Stars in Open Clusters: A Test of the Helium Flash Mechanism

NASA Technical Reports Server (NTRS)

Carlberg, Joleen K.; Cunha, Katia; Smith, Verne V.

2016-01-01

The temperature distribution of field Li-rich red giants suggests the presence of a population of Li-rich red clump (RC) stars. One proposed explanation for this population is that all stars with masses near 2 solar mass experience a shortlived phase of Li-richness at the onset of core He-burning. Many of these stars have low C-12/C-13, a signature of deep mixing that is presumably associated with the Li regeneration. To test this purported mechanism of Li enrichment, we measured abundances in 38 RC stars and 6 red giant branch (RGB) stars in four open clusters selected to have RC masses near 2 solar mass. We find six Li-rich stars (A(Li) greater than or equal to 1.50 dex) of which only two may be RC stars. None of the RC stars have Li exceeding the levels observed in the RGB stars, but given the brevity of the suggested Li-rich phase and the modest sample size, it is probable that stars with larger Li-enrichments were missed simply by chance. However, we find very few stars in our sample with low C-12/C-13. Such low C-12/C-13, seen in many field Li-rich stars, should persist even after lithium has returned to normal low levels. Thus, if Li synthesis during the He flash occurs, it is a rare, but potentially long-lived occurrence rather than a short-lived phase for all stars. We estimate a conservative upper limit of the fraction of stars going through a Li-rich phase to be less than 47%, based on stars that have low C-12/C-13 for their observed A(Li).

Design and results of the pretest of the IDEFICS study.

PubMed

Suling, M; Hebestreit, A; Peplies, J; Bammann, K; Nappo, A; Eiben, G; Alvira, J M Fernández; Verbestel, V; Kovács, E; Pitsiladis, Y P; Veidebaum, T; Hadjigeorgiou, C; Knof, K; Ahrens, W

2011-04-01

During the preparatory phase of the baseline survey of the IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study, standardised survey procedures including instruments, examinations, methods, biological sampling and software tools were developed and pretested for their feasibility, robustness and acceptability. A pretest was conducted of full survey procedures in 119 children aged 2-9 years in nine European survey centres (N(per centre)=4-27, mean 13.22). Novel techniques such as ultrasound measurements to assess subcutaneous fat and bone health, heart rate monitors combined with accelerometers and sensory taste perception tests were used. Biological sampling, physical examinations, sensory taste perception tests, parental questionnaire and medical interview required only minor amendments, whereas physical fitness tests required major adaptations. Callipers for skinfold measurements were favoured over ultrasonography, as the latter showed only a low-to-modest agreement with calliper measurements (correlation coefficients of r=-0.22 and r=0.67 for all children). The combination of accelerometers with heart rate monitors was feasible in school children only. Implementation of the computer-based 24-h dietary recall required a complex and intensive developmental stage. It was combined with the assessment of school meals, which was changed after the pretest from portion weighing to the more feasible observation of the consumed portion size per child. The inclusion of heel ultrasonometry as an indicator of bone stiffness was the most important amendment after the pretest. Feasibility and acceptability of all procedures had to be balanced against their scientific value. Extensive pretesting, training and subsequent refinement of the methods were necessary to assess the feasibility of all instruments and procedures in routine fieldwork and to exchange or modify procedures that would otherwise give invalid or misleading results.

Variations in BMI and prevalence of health risks in diverse racial and ethnic populations.

PubMed

Stommel, Manfred; Schoenborn, Charlotte A

2010-09-01

When examining health risks associated with the BMI, investigators often rely on the customary BMI thresholds of the 1995 World Health Organization report. However, within-interval variations in morbidity and mortality can be substantial, and the thresholds do not necessarily correspond to identifiable risk increases. Comparing the prevalence of hypertension, diabetes, coronary heart disease (CHD), asthma, and arthritis among non-Hispanic whites, blacks, East Asians and Hispanics, we examine differences in the BMI-health-risk relationships for small BMI increments. The analysis is based on 11 years of data of the National Health Interview Survey (NHIS), with a sample size of 337,375 for the combined 1997-2007 Sample Adult. The analysis uses multivariate logistic regression models, employing a nonparametric approach to modeling the BMI-health-risk relationship, while relying on narrowly defined BMI categories. Rising BMI levels are associated with higher levels of chronic disease burdens in four major racial and ethnic groups, even after adjusting for many socio-demographic characteristics and three important health-related behaviors (smoking, physical activity, alcohol consumption). For all population groups, except East Asians, a modestly higher disease risk was noted for persons with a BMI <20 compared with persons with BMI in the range of 20-21. Using five chronic conditions as risk criteria, a categorization of the BMI into normal weight, overweight, or obesity appears arbitrary. Although the prevalence of disease risks differs among racial and ethnic groups regardless of BMI levels, the evidence presented here does not support the notion that the BMI-health-risk profile of East Asians and others warrants race-specific BMI cutoff points.

Systematic Review of Behavioral Weight Management Program MOVE! for Veterans.

PubMed

Maciejewski, Matthew L; Shepherd-Banigan, Megan; Raffa, Susan D; Weidenbacher, Hollis J

2018-05-01

Since 2006, the Veterans Health Administration has delivered a population-based behavioral weight management program (MOVE!) to Veterans, which numerous studies have examined. The purpose of this study was to systematically review these studies to understand MOVE! participation rates and the association between MOVE! participation and weight change. A December 2016 PubMed search identified 320 English-language abstracts published between January 1, 2005 and December 31, 2016, of which 42 underwent full-text review. Twenty-six articles were determined to be eligible for final inclusion and data elements extracted from these articles included study years, study design, content of MOVE! and control intervention (if any), inclusion/exclusion criteria, initial sample size and sample loss, intervention duration and follow-up, patient characteristics, and outcomes. Quality was assessed using the Newcastle-Ottawa Quality Scale. Studies were judged to be of good quality. Twenty-one of the 26 studies were retrospective cohort studies, one was a prospective cohort study and four were randomized trials. Program participation varied substantially (2%-12%) across studies. Six-month weight loss ranged from -0.95 kg to -1.84 kg, whereas 12-month weight loss ranged from -0.13 kg to -3.3 kg. A maximum of 25% of MOVE! users engaged in intense and sustained participation (eight or more visits within 6 months), but higher participation levels were consistently associated with greater weight change (-1.18 kg to -5.3 kg at 6 months, -1.68 kg to -3.58 kg at 12 months). MOVE! participation is associated with modest short-term weight loss, with greater weight loss as participation increases. More research is needed to understand the barriers and facilitators to participation and the effect of MOVE! participation on long-term health and economic outcomes. Published by Elsevier Inc.

Digital altruists: Resolving key questions about the empathy-altruism hypothesis in an Internet sample.

PubMed

McAuliffe, William H B; Forster, Daniel E; Philippe, Joachner; McCullough, Michael E

2018-06-01

Researchers have identified the capacity to take the perspective of others as a precursor to empathy-induced altruistic motivation. Consequently, investigators frequently use so-called perspective-taking instructions to manipulate empathic concern. However, most experiments using perspective-taking instructions have had modest sample sizes, undermining confidence in the replicability of results. In addition, it is unknown whether perspective-taking instructions work because they increase empathic concern or because comparison conditions reduce empathic concern (or both). Finally, some researchers have found that egoistic factors that do not involve empathic concern, including self-oriented emotions and self-other overlap, mediate the relationship between perspective-taking instructions and helping. The present investigation was a high-powered, preregistered effort that addressed methodological shortcomings of previous experiments to clarify how and when perspective-taking manipulations affect emotional arousal and prosocial motivation in a prototypical experimental paradigm administered over the Internet. Perspective-taking instructions did not clearly increase empathic concern; this null finding was not due to ceiling effects. Instructions to remain objective, on the other hand, unequivocally reduced empathic concern relative to a no-instructions control condition. Empathic concern was the most strongly felt emotion in all conditions, suggesting that distressed targets primarily elicit other-oriented concern. Empathic concern uniquely predicted the quality of social support provided to the target, which supports the empathy-altruism hypothesis and contradicts the role of self-oriented emotions and self-other overlap in explaining helping behavior. Empathy-induced altruism may be responsible for many prosocial acts that occur in everyday settings, including the increasing number of prosocial acts that occur online. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Two-generation analysis of pollen flow across a landscape. I. Male gamete heterogeneity among females.

PubMed

Smouse, P E; Dyer, R J; Westfall, R D; Sork, V L

2001-02-01

Gene flow is a key factor in the spatial genetic structure in spatially distributed species. Evolutionary biologists interested in microevolutionary processess and conservation biologists interested in the impact of landscape change require a method that measures the real time process of gene movement. We present a novel two-generation (parent-offspring) approach to the study of genetic structure (TwoGener) that allows us to quantify heterogeneity among the male gamete pools sampled by maternal trees scattered across the landscape and to estimate mean pollination distance and effective neighborhood size. First, we describe the model's elements: genetic distance matrices to estimate intergametic distances, molecular analysis of variance to determine whether pollen profiles differ among mothers, and optimal sampling considerations. Second, we evaluate the model's effectiveness by simulating spatially distributed populations. Spatial heterogeneity in male gametes can be estimated by phiFT, a male gametic analogue of Wright's F(ST) and an inverse function of mean pollination distance. We illustrate TwoGener in cases where the male gamete can be categorically or ambiguously determined. This approach does not require the high level of genetic resolution needed by parentage analysis, but the ambiguous case is vulnerable to bias in the absence of adequate genetic resolution. Finally, we apply TwoGener to an empirical study of Quercus alba in Missouri Ozark forests. We find that phiFT = 0.06, translating into about eight effective pollen donors per female and an effective pollination neighborhood as a circle of radius about 17 m. Effective pollen movement in Q. alba is more restricted than previously realized, even though pollen is capable of moving large distances. This case study illustrates that, with a modest investment in field survey and laboratory analysis, the TwoGener approach permits inferences about landscape-level gene movements.

Treatment of Suicide Attempters With Bipolar Disorder: A Randomized Clinical Trial Comparing Lithium and Valproate in the Prevention of Suicidal Behavior

PubMed Central

Oquendo, Maria A.; Galfalvy, Hanga C.; Currier, Dianne; Grunebaum, Michael F.; Sher, Leo; Sullivan, Gregory M.; Burke, Ainsley K.; Harkavy-Friedman, Jill; Sublette, M. Elizabeth; Parsey, Ramin V.; Mann, J. John

2013-01-01

Objective Bipolar disorder is associated with high risk for suicidal acts. Observational studies suggest a protective effect of lithium against suicidal behavior. However, testing this effect in randomized clinical trials is logistically and ethically challenging. The authors tested the hypothesis that lithium offers bipolar patients with a history of suicide attempt greater protection against suicidal behavior compared to valproate. Method Patients with bipolar disorder and past suicide attempts (N=98) were randomly assigned to treatment with lithium or valproate, plus adjunctive medications as indicated, in a double-blind 2.5-year trial. An intent-to-treat analysis was performed using the log-rank test for survival data. Two models were fitted: time to suicide attempt and time to suicide event (attempt or hospitalization or change in medication in response to suicide plans). Results There were 45 suicide events in 35 participants, including 18 suicide attempts made by 14 participants, six from the lithium group and eight from the valproate group. There were no suicides. Intent-to-treat analysis using the log-rank test showed no differences between treatment groups in time to suicide attempt or to suicide event. Post hoc power calculations revealed that the modest sample size, reflective of challenges in recruitment, only permits detection of a relative risk of 5 or greater. Conclusions Despite the high frequency of suicide events during the study, this randomized controlled trial detected no difference between lithium and valproate in time to suicide attempt or suicide event in a sample of suicide attempters with bipolar disorder. However, smaller clinically significant differences between the two drugs were not ruled out. PMID:21768611

Teaching infant car seat installation via interactive visual presence: An experimental trial.

PubMed

Schwebel, David C; Johnston, Anna; Rouse, Jenni

2017-02-17

A large portion of child restraint systems (car seats) are installed incorrectly, especially when first-time parents install infant car seats. Expert instruction greatly improves the accuracy of car seat installation but is labor intensive and difficult to obtain for many parents. This study was designed to evaluate the efficacy of 3 ways of communicating instructions for proper car seat installation: phone conversation; HelpLightning, a mobile application (app) that offers virtual interactive presence permitting both verbal and interactive (telestration) visual communication; and the manufacturer's user manual. A sample of 39 young adults of child-bearing age who had no previous experience installing car seats were recruited and randomly assigned to install an infant car seat using guidance from one of those 3 communication sources. Both the phone and interactive app were more effective means to facilitate accurate car seat installation compared to the user manual. There was a trend for the app to offer superior communication compared to the phone, but that difference was not significant in most assessments. The phone and app groups also installed the car seat more efficiently and perceived the communication to be more effective and their installation to be more accurate than those in the user manual group. Interactive communication may help parents install car seats more accurately than using the manufacturer's manual alone. This was an initial study with a modestly sized sample; if results are replicated in future research, there may be reason to consider centralized "call centers" that provide verbal and/or interactive visual instruction from remote locations to parents installing car seats, paralleling the model of centralized Poison Control centers in the United States.

Validation of a Korean MMPI-2 Hwa-Byung scale using a Korean normative sample.

PubMed

Ketterer, Holly; Han, Kyunghee; Weed, Nathan C

2010-07-01

The psychometric properties of a recently developed measure of Hwa-Byung (HB), a Korean culture bound syndrome, using an updated version of the Korean Minnesota Multiphasic Personality Inventory-2, were examined in Korean normative sample. Confirmatory factor analyses indicated that both the first-order four-factor model and the single second-order factor model fit the data well, but the latter may be superior because of its parsimony. The HB scale correlated modestly with age, sex, SES, and problems with family and finance. However, it showed substantial correlations with spouse ratings items that were identified a priori as prospective HB correlates, indicating excellent concurrent validity. The limitations of the study and the need for future studies employing HB patients were discussed.

Enhanced sampling simulations of DNA step parameters.

PubMed

Karolak, Aleksandra; van der Vaart, Arjan

2014-12-15

A novel approach for the selection of step parameters as reaction coordinates in enhanced sampling simulations of DNA is presented. The method uses three atoms per base and does not require coordinate overlays or idealized base pairs. This allowed for a highly efficient implementation of the calculation of all step parameters and their Cartesian derivatives in molecular dynamics simulations. Good correlation between the calculated and actual twist, roll, tilt, shift, and slide parameters is obtained, while the correlation with rise is modest. The method is illustrated by its application to the methylated and unmethylated 5'-CATGTGACGTCACATG-3' double stranded DNA sequence. One-dimensional umbrella simulations indicate that the flexibility of the central CG step is only marginally affected by methylation. © 2014 Wiley Periodicals, Inc.

Disk galaxy scaling relations at intermediate redshifts. I. The Tully-Fisher and velocity-size relations

NASA Astrophysics Data System (ADS)

Böhm, Asmus; Ziegler, Bodo L.

2016-07-01

Aims: Galaxy scaling relations such as the Tully-Fisher relation (between the maximum rotation velocity Vmax and luminosity) and the velocity-size relation (between Vmax and the disk scale length) are powerful tools to quantify the evolution of disk galaxies with cosmic time. Methods: We took spatially resolved slit spectra of 261 field disk galaxies at redshifts up to z ≈ 1 using the FORS instruments of the ESO Very Large Telescope. The targets were selected from the FORS Deep Field and William Herschel Deep Field. Our spectroscopy was complemented with HST/ACS imaging in the F814W filter. We analyzed the ionized gas kinematics by extracting rotation curves from the two-dimensional spectra. Taking into account all geometrical, observational, and instrumental effects, these rotation curves were used to derive the intrinsic Vmax. Results: Neglecting galaxies with disturbed kinematics or insufficient spatial rotation curve extent, Vmax was reliably determined for 124 galaxies covering redshifts 0.05 < z < 0.97. This is one of the largest kinematic samples of distant disk galaxies to date. We compared this data set to the local B-band Tully-Fisher relation and the local velocity-size relation. The scatter in both scaling relations is a factor of ~2 larger at z ≈ 0.5 than at z ≈ 0. The deviations of individual distant galaxies from the local Tully-Fisher relation are systematic in the sense that the galaxies are increasingly overluminous toward higher redshifts, corresponding to an overluminosity ΔMB = -(1.2 ± 0.5) mag at z = 1. This luminosity evolution at given Vmax is probably driven by younger stellar populations of distant galaxies with respect to their local counterparts, potentially combined with modest changes in dark matter mass fractions. The analysis of the velocity-size relation reveals that disk galaxies of a given Vmax have grown in size by a factor of ~1.5 over the past ~8 Gyr, most likely through accretion of cold gas and/or small satellites. From scrutinizing the combined evolution in luminosity and size, we find that the galaxies that show the strongest evolution toward smaller sizes at z ≈ 1 are not those that feature the strongest evolution in luminosity, and vice versa. Based on observations with the European Southern Observatory Very Large Telescope (ESO-VLT), observing run IDs 65.O-0049, 66.A-0547, 68.A-0013, 69.B-0278B, 70.B-0251A and 081.B-0107A.The full Table 1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/592/A64

Sequential sampling: a novel method in farm animal welfare assessment.

PubMed

Heath, C A E; Main, D C J; Mullan, S; Haskell, M J; Browne, W J

2016-02-01

Lameness in dairy cows is an important welfare issue. As part of a welfare assessment, herd level lameness prevalence can be estimated from scoring a sample of animals, where higher levels of accuracy are associated with larger sample sizes. As the financial cost is related to the number of cows sampled, smaller samples are preferred. Sequential sampling schemes have been used for informing decision making in clinical trials. Sequential sampling involves taking samples in stages, where sampling can stop early depending on the estimated lameness prevalence. When welfare assessment is used for a pass/fail decision, a similar approach could be applied to reduce the overall sample size. The sampling schemes proposed here apply the principles of sequential sampling within a diagnostic testing framework. This study develops three sequential sampling schemes of increasing complexity to classify 80 fully assessed UK dairy farms, each with known lameness prevalence. Using the Welfare Quality herd-size-based sampling scheme, the first 'basic' scheme involves two sampling events. At the first sampling event half the Welfare Quality sample size is drawn, and then depending on the outcome, sampling either stops or is continued and the same number of animals is sampled again. In the second 'cautious' scheme, an adaptation is made to ensure that correctly classifying a farm as 'bad' is done with greater certainty. The third scheme is the only scheme to go beyond lameness as a binary measure and investigates the potential for increasing accuracy by incorporating the number of severely lame cows into the decision. The three schemes are evaluated with respect to accuracy and average sample size by running 100 000 simulations for each scheme, and a comparison is made with the fixed size Welfare Quality herd-size-based sampling scheme. All three schemes performed almost as well as the fixed size scheme but with much smaller average sample sizes. For the third scheme, an overall association between lameness prevalence and the proportion of lame cows that were severely lame on a farm was found. However, as this association was found to not be consistent across all farms, the sampling scheme did not prove to be as useful as expected. The preferred scheme was therefore the 'cautious' scheme for which a sampling protocol has also been developed.

Novel joint selection methods can reduce sample size for rheumatoid arthritis clinical trials with ultrasound endpoints.

PubMed

Allen, John C; Thumboo, Julian; Lye, Weng Kit; Conaghan, Philip G; Chew, Li-Ching; Tan, York Kiat

2018-03-01

To determine whether novel methods of selecting joints through (i) ultrasonography (individualized-ultrasound [IUS] method), or (ii) ultrasonography and clinical examination (individualized-composite-ultrasound [ICUS] method) translate into smaller rheumatoid arthritis (RA) clinical trial sample sizes when compared to existing methods utilizing predetermined joint sites for ultrasonography. Cohen's effect size (ES) was estimated (ES^) and a 95% CI (ES^L, ES^U) calculated on a mean change in 3-month total inflammatory score for each method. Corresponding 95% CIs [nL(ES^U), nU(ES^L)] were obtained on a post hoc sample size reflecting the uncertainty in ES^. Sample size calculations were based on a one-sample t-test as the patient numbers needed to provide 80% power at α = 0.05 to reject a null hypothesis H 0 : ES = 0 versus alternative hypotheses H 1 : ES = ES^, ES = ES^L and ES = ES^U. We aimed to provide point and interval estimates on projected sample sizes for future studies reflecting the uncertainty in our study ES^S. Twenty-four treated RA patients were followed up for 3 months. Utilizing the 12-joint approach and existing methods, the post hoc sample size (95% CI) was 22 (10-245). Corresponding sample sizes using ICUS and IUS were 11 (7-40) and 11 (6-38), respectively. Utilizing a seven-joint approach, the corresponding sample sizes using ICUS and IUS methods were nine (6-24) and 11 (6-35), respectively. Our pilot study suggests that sample size for RA clinical trials with ultrasound endpoints may be reduced using the novel methods, providing justification for larger studies to confirm these observations. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

Effects of tree-to-tree variations on sap flux-based transpiration estimates in a forested watershed

NASA Astrophysics Data System (ADS)

Kume, Tomonori; Tsuruta, Kenji; Komatsu, Hikaru; Kumagai, Tomo'omi; Higashi, Naoko; Shinohara, Yoshinori; Otsuki, Kyoichi

2010-05-01

To estimate forest stand-scale water use, we assessed how sample sizes affect confidence of stand-scale transpiration (E) estimates calculated from sap flux (Fd) and sapwood area (AS_tree) measurements of individual trees. In a Japanese cypress plantation, we measured Fd and AS_tree in all trees (n = 58) within a 20 × 20 m study plot, which was divided into four 10 × 10 subplots. We calculated E from stand AS_tree (AS_stand) and mean stand Fd (JS) values. Using Monte Carlo analyses, we examined potential errors associated with sample sizes in E, AS_stand, and JS by using the original AS_tree and Fd data sets. Consequently, we defined optimal sample sizes of 10 and 15 for AS_stand and JS estimates, respectively, in the 20 × 20 m plot. Sample sizes greater than the optimal sample sizes did not decrease potential errors. The optimal sample sizes for JS changed according to plot size (e.g., 10 × 10 m and 10 × 20 m), while the optimal sample sizes for AS_stand did not. As well, the optimal sample sizes for JS did not change in different vapor pressure deficit conditions. In terms of E estimates, these results suggest that the tree-to-tree variations in Fd vary among different plots, and that plot size to capture tree-to-tree variations in Fd is an important factor. This study also discusses planning balanced sampling designs to extrapolate stand-scale estimates to catchment-scale estimates.

Co-creation of market expansion in point-of-care testing in the United States: Industry leadership perspectives on the community pharmacy segment.

PubMed

Hohmeier, Kenneth C; McDonough, Sharon L K; Wang, Junling

Point-of-care testing (POCT) is a specialty of laboratory medicine that occurs at the bedside or near the patient when receiving health services. Despite its established clinical utility and consumer demand in the community pharmacy, the implementation of POCT within this setting has remained modest for a variety of reasons. One possible solution to this problem is the concept of co-creation - the partnership between consumer and manufacturer in the development of value for a service or device. Using the theoretical underpinning of co-creation, this study aimed to investigate perceptions of point-of-care-testing (POCT) industry leadership on the community pharmacy market in the United States to uncover reasons for limited implementation within community pharmacies. Participants were recruited for this study through the use of snowball sampling. A series of semi-structured interviews were conducted with the participants via telephone. Interviews were recorded, transcribed, and entered into a qualitative analysis software program to summarize the data. Five key themes were uncovered: gaps in understanding, areas of positive impact, barriers to implementation, facilitators of implementation, and community pharmacy - a potential major player. Through uncovering gaps in perceptions, it may be possible to leverage the U.S. pharmacy industry's size, potential for scalability, and ease of patient access to further patient care. Copyright © 2016 Elsevier Inc. All rights reserved.

Efficacy and predictability of soft tissue ablation using a prototype Raman-shifted alexandrite laser

NASA Astrophysics Data System (ADS)

Kozub, John A.; Shen, Jin-H.; Joos, Karen M.; Prasad, Ratna; Shane Hutson, M.

2015-10-01

Previous research showed that mid-infrared free-electron lasers could reproducibly ablate soft tissue with little collateral damage. The potential for surgical applications motivated searches for alternative tabletop lasers providing thermally confined pulses in the 6- to-7-μm wavelength range with sufficient pulse energy, stability, and reliability. Here, we evaluate a prototype Raman-shifted alexandrite laser. We measure ablation thresholds, etch rates, and collateral damage in gelatin and cornea as a function of laser wavelength (6.09, 6.27, or 6.43 μm), pulse energy (up to 3 mJ/pulse), and spot diameter (100 to 600 μm). We find modest wavelength dependence for ablation thresholds and collateral damage, with the lowest thresholds and least damage for 6.09 μm. We find a strong spot-size dependence for all metrics. When the beam is tightly focused (˜100-μm diameter), ablation requires more energy, is highly variable and less efficient, and can yield large zones of mechanical damage (for pulse energies >1 mJ). When the beam is softly focused (˜300-μm diameter), ablation proceeded at surgically relevant etch rates, with reasonable reproducibility (5% to 12% within a single sample), and little collateral damage. With improvements in pulse-energy stability, this prototype laser may have significant potential for soft-tissue surgical applications.

A Review of Smartphone Applications for Promoting Physical Activity.

PubMed

Coughlin, Steven S; Whitehead, Mary; Sheats, Joyce Q; Mastromonico, Jeff; Smith, Selina

Rapid developments in technology have encouraged the use of smartphones in health promotion research and practice. Although many applications (apps) relating to physical activity are available from major smartphone platforms, relatively few have been tested in research studies to determine their effectiveness in promoting health. In this article, we summarize data on use of smartphone apps for promoting physical activity based upon bibliographic searches with relevant search terms in PubMed and CINAHL. After screening the abstracts or full texts of articles, 15 eligible studies of the acceptability or efficacy of smartphone apps for increasing physical activity were identified. Of the 15 included studies, 6 were qualitative research studies, 8 were randomized control trials, and one was a nonrandomized study with a pre-post design. The results indicate that smartphone apps can be efficacious in promoting physical activity although the magnitude of the intervention effect is modest. Participants of various ages and genders respond favorably to apps that automatically track physical activity (e.g., steps taken), track progress toward physical activity goals, and are user-friendly and flexible enough for use with several types of physical activity. Future studies should utilize randomized controlled trial research designs, larger sample sizes, and longer study periods to establish the physical activity measurement and intervention capabilities of smartphones. There is a need for culturally appropriate, tailored health messages to increase knowledge and awareness of health behaviors such as physical activity.

Association of tagSNPs in the urokinase-plasminogen activator (PLAU) gene with Alzheimer's disease and associated quantitative traits.

PubMed

Ozturk, Ayla; Minster, Ryan L; DeKosky, Steven T; Kamboh, M Ilyas

2007-01-05

The gene coding for urokinase-plasminogen activator (PLAU) is a strong biological and positional candidate gene for Alzheimer's disease (AD). Previously some studies have examined the role of common variation in the PLAU gene with AD risk but the results have been inconsistent and this inconsistency could have been due to the use of relatively small sample sizes. In this study we evaluated the distribution of four tagSNPs (rs2227562 in intron 5, rs2227564 in exon 6, rs2227571 in intron 9, and rs4065 in 3'UTR) in the PLAU gene in a large case-control study consisting of up to 1,000 AD patients and 697 white control subjects. We examined the role of these tagSNPs with AD risk and quantitative traits of AD, including age-at-onset (AAO), disease duration, and mini-mental state examination (MMSE) scores. The 3'UTR SNP revealed modest significant association with risk (OR = 0.71, 95% CI: 0.53-0.95; P = 0.02), AAO (P = 0.036) and disease duration (P = 0.04) of AD. In addition, the intron 9 SNP also revealed a significant association with AAO (P = 0.01) and disease duration (P = 0.006). Our data on a large number of AD cases and controls suggest that genetic variation in PLAU may affect the risk and AAO of AD.

Efficacy and predictability of soft tissue ablation using a prototype Raman-shifted alexandrite laser

PubMed Central

Kozub, John A.; Shen, Jin-H.; Joos, Karen M.; Prasad, Ratna; Shane Hutson, M.

2015-01-01

Abstract. Previous research showed that mid-infrared free-electron lasers could reproducibly ablate soft tissue with little collateral damage. The potential for surgical applications motivated searches for alternative tabletop lasers providing thermally confined pulses in the 6- to-7-μm wavelength range with sufficient pulse energy, stability, and reliability. Here, we evaluate a prototype Raman-shifted alexandrite laser. We measure ablation thresholds, etch rates, and collateral damage in gelatin and cornea as a function of laser wavelength (6.09, 6.27, or 6.43  μm), pulse energy (up to 3  mJ/pulse), and spot diameter (100 to 600  μm). We find modest wavelength dependence for ablation thresholds and collateral damage, with the lowest thresholds and least damage for 6.09  μm. We find a strong spot-size dependence for all metrics. When the beam is tightly focused (∼100-μm diameter), ablation requires more energy, is highly variable and less efficient, and can yield large zones of mechanical damage (for pulse energies >1  mJ). When the beam is softly focused (∼300-μm diameter), ablation proceeded at surgically relevant etch rates, with reasonable reproducibility (5% to 12% within a single sample), and little collateral damage. With improvements in pulse-energy stability, this prototype laser may have significant potential for soft-tissue surgical applications. PMID:26456553

Patterns of cortisol and alpha-amylase reactivity to psychosocial stress in maltreated women.

PubMed

Mielock, Alyssa S; Morris, Matthew C; Rao, Uma

2017-02-01

Childhood maltreatment can trigger enduring changes in major stress response systems, particularly in the context of major depressive disorder (MDD). However, the relative impact of maltreatment versus MDD on hypothalamic-pituitary-adrenal axis and sympathetic-adrenal-medullary system stress reactivity is not well understood. This study examined salivary cortisol and alpha-amylase responses to the Trier Social Stress Test (TSST) in 26 maltreated (15 with current MDD) and 26 non-maltreated (17 with current MDD) women. Maltreated women showed greater anticipatory cortisol reactivity during the TSST protocol compared to non-maltreated women. Maltreated women also showed rapid deceleration in cortisol levels. Whereas non-maltreated women showed initial declines in alpha-amylase levels but rapidly increasing alpha-amylase levels during the TSST protocol, maltreated women did not exhibit changes in alpha-amylase levels during the TSST protocol. Contrary to expectation, MDD did not impact cortisol or alpha-amylase responses. The present study is limited by retrospective report of childhood maltreatment, cross-sectional design, and modest sample sizes. These findings suggest that childhood maltreatment plays a greater role driving alterations in cortisol and alpha-amylase stress reactivity than MDD. Understanding the biological embedding of maltreatment is critical for elucidating mechanisms linking these experiences to risk for negative mental and physical health outcomes. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of lamotrigine on hippocampal activation in corticosteroid-treated patients.

PubMed

Brown, E Sherwood; Zaidel, Liam; Allen, Greg; McColl, Roderick; Vazquez, Miguel; Ringe, Wendy K

2010-11-01

An extensive animal literature suggests that stress or excessive corticosteroid exposure is associated with changes in hippocampal function and memory. These findings are pertinent to psychiatric disorders with elevated cortisol, Cushing's disease and the millions of patients receiving prescription corticosteroids. In animals, agents that decrease glutamate release attenuate the effects of corticosteroids on the hippocampus. Minimal data are available on preventing or reversing the effects of corticosteroids on the human hippocampus. We previously reported improvement in memory in corticosteroid-treated patients given lamotrigine. In this report, we examined the impact of lamotrigine on task-related hippocampal activation in patients taking prescription corticosteroids. A total of 28 outpatients taking long-term oral prednisone for medical conditions, such as renal transplant rejection, were randomized to lamotrigine or placebo for 24 weeks. Hippocampal activation in response to a visual memory task was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI). Consistent with a reduction in glutamate release, the right posterior hippocampus showed a significant decrease in task-related activation in the lamotrigine group as compared to the placebo group. The modest sample size and an assessment period of only 24 weeks are study limitations. Between-group differences in hippocampal activation were observed. The results suggest that an agent that modulates glutamate may modify the effects of long-term corticosteroid exposure on the human hippocampus. Copyright © 2010 Elsevier B.V. All rights reserved.

Boomerang: A method for recursive reclassification.

PubMed

Devlin, Sean M; Ostrovnaya, Irina; Gönen, Mithat

2016-09-01

While there are many validated prognostic classifiers used in practice, often their accuracy is modest and heterogeneity in clinical outcomes exists in one or more risk subgroups. Newly available markers, such as genomic mutations, may be used to improve the accuracy of an existing classifier by reclassifying patients from a heterogenous group into a higher or lower risk category. The statistical tools typically applied to develop the initial classifiers are not easily adapted toward this reclassification goal. In this article, we develop a new method designed to refine an existing prognostic classifier by incorporating new markers. The two-stage algorithm called Boomerang first searches for modifications of the existing classifier that increase the overall predictive accuracy and then merges to a prespecified number of risk groups. Resampling techniques are proposed to assess the improvement in predictive accuracy when an independent validation data set is not available. The performance of the algorithm is assessed under various simulation scenarios where the marker frequency, degree of censoring, and total sample size are varied. The results suggest that the method selects few false positive markers and is able to improve the predictive accuracy of the classifier in many settings. Lastly, the method is illustrated on an acute myeloid leukemia data set where a new refined classifier incorporates four new mutations into the existing three category classifier and is validated on an independent data set. © 2016, The International Biometric Society.

Boomerang: A Method for Recursive Reclassification

PubMed Central

Devlin, Sean M.; Ostrovnaya, Irina; Gönen, Mithat

2016-01-01

Summary While there are many validated prognostic classifiers used in practice, often their accuracy is modest and heterogeneity in clinical outcomes exists in one or more risk subgroups. Newly available markers, such as genomic mutations, may be used to improve the accuracy of an existing classifier by reclassifying patients from a heterogenous group into a higher or lower risk category. The statistical tools typically applied to develop the initial classifiers are not easily adapted towards this reclassification goal. In this paper, we develop a new method designed to refine an existing prognostic classifier by incorporating new markers. The two-stage algorithm called Boomerang first searches for modifications of the existing classifier that increase the overall predictive accuracy and then merges to a pre-specified number of risk groups. Resampling techniques are proposed to assess the improvement in predictive accuracy when an independent validation data set is not available. The performance of the algorithm is assessed under various simulation scenarios where the marker frequency, degree of censoring, and total sample size are varied. The results suggest that the method selects few false positive markers and is able to improve the predictive accuracy of the classifier in many settings. Lastly, the method is illustrated on an acute myeloid leukemia dataset where a new refined classifier incorporates four new mutations into the existing three category classifier and is validated on an independent dataset. PMID:26754051

Single nucleotide polymorphisms in obesity-related genes and the risk of esophageal cancers.

PubMed

Doecke, James D; Zhao, Zhen Zhen; Stark, Mitchell S; Green, Adèle C; Hayward, Nicholas K; Montgomery, Grant W; Webb, Penelope M; Whiteman, David C

2008-04-01

Rates of adenocarcinoma of the esophagus (EAC) and esophagogastric junction (EGJAC) have been rising rapidly in recent decades, in contrast to the declining rates of esophageal squamous cell carcinomas (ESCC). Obesity is a major risk factor for both EAC and EGJAC, but not ESCC, and there is speculation that obesity promotes adenocarcinoma development through endocrine and related pathways. We therefore compared the prevalence of 12 single nucleotide polymorphisms (SNPs) in nine candidate genes previously implicated in obesity pathways (LEP, LEPR, ADIPOQ, POMC, PPARalpha, PPARgamma, RXRgamma, GHRL, and INSIG2) in a large Australian case-control study comprising DNA samples from 260 EAC cases, 301 EGJAC cases, 213 ESCC cases, and 1,352 population controls. No SNPs were associated with EGJAC or ESCC. Although several SNPs seemed to be associated with EAC on crude analysis [ADIPOQ (rs1501299), LEP (5'-untranslated region), PPARgamma (H447H), and GHRL (M72L)], effect sizes were modest and none of the associations was significant after correcting for multiple comparisons. Further, we found no consistent evidence that any of the genotypes were associated with risk of EAC or EGJAC within strata of body mass index (<25.0 kg/m(2), 25.0-29.9 kg/m(2), >30 kg/m(2)). In conclusion, our data suggest that these SNPs do not play a major role in esophageal carcinogenesis.

metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis.

PubMed

Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

2016-07-01

A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness.Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Code is available at https://github.com/aalto-ics-kepaco anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.