Insufficient rest or sleep and its relation to cardiovascular disease, diabetes and obesity in a national, multiethnic sample.

PubMed

Shankar, Anoop; Syamala, Shirmila; Kalidindi, Sita

2010-11-30

A new question on insufficient rest/sleep was included in the 2008 Behavioral Risk Factor Surveillance System (BRFSS) for the 50 states, District of Columbia, and three US territories. No previous study, however, has examined perceived insufficient rest/sleep in relation to cardiovascular disease (CVD) or diabetes mellitus. We examined the association between self-reported insufficient rest/sleep and CVD, diabetes, and obesity in a contemporary sample of US adults. Multiethnic, nationally representative, cross-sectional survey (2008 BRFSS) participants were >20 years of age (n=372, 144, 50% women). Self-reported insufficient rest/sleep in the previous month was categorized into four groups: zero, 1-13, 14-29, and 30 days. There were five outcomes: 1) any CVD, 2) coronary heart disease (CHD), 3) stroke, 4) diabetes mellitus, and 5) obesity (body mass index≥30 kg/m2). We employed multivariable logistic regression to calculate odds ratio (OR), (95% confidence interval (CI), of increasing categories of insufficient rest/sleep, taking zero days of insufficient rest/sleep as the referent category. Insufficient rest/sleep was found to be associated with 1) any CVD, 2) CHD, 3) stroke, 4) diabetes mellitus, and 5) obesity, in separate analyses. Compared to those reporting zero days of insufficient sleep (referent), the OR (95% CI) associated with all 30 days of insufficient sleep was 1.67 (1.55-1.79) for any cardiovascular disease, 1.69(1.56-1.83) for CHD, 1.51(1.36-1.68) for stroke, 1.31(1.21-1.41) for diabetes, and 1.51 (1.43-1.59) for obesity. In a multiethnic sample of US adults, perceived insufficient rest/sleep was found to be independently associated with CHD, stroke, diabetes mellitus and obesity.

Autologous platelet-rich plasma in the treatment of venous leg ulcers in primary care: a randomised controlled, pilot study.

PubMed

Burgos-Alonso, Natalia; Lobato, Igone; Hernández, Igone; Sebastian, Kepa San; Rodríguez, Begoña; March, Anna Giné; Perez-Salvador, Adriana; Arce, Veronica; Garcia-Alvarez, Arturo; Gomez-Fernandez, Maria Cruz; Grandes, Gonzalo; Andia, Isabel

2018-06-01

To examine the potential efficacy and safety of autologous platelet-rich plasma (PRP) in comparison with the conventional treatment (standard care, SoC) for the treatment of leg ulcers in patients with chronic venous insufficiency, in a primary health-care setting. A Phase I-II, open-label, parallel-group, multicentre, randomised pilot study was conducted. The outcome variables at baseline and at weeks five and nine included reduction in the ulcer area, Chronic Venous Insufficiency Quality of Life Questionnaire score, cost of the treatment for up to nine weeks and average weekly cure rate. A total of eight patients, each with at least a six-month history of venous leg ulcer (VLUs), were included in the study. A total of 12 ulcers were treated with either autologous PRP or standard SoC. Patients treated with PRP required wound care only once per week. In the SoC group, patients required intervention 2-3 times per week. A reduction in the mean ulcer size in the PRP group was 3.9cm 2 compared with the SoC group at 3.2cm 2 , although the sample size was insufficient to reach statistical significance. Improvement in quality of life (QoL) score was observed in the patients in the PRP group. This study offers proof-of-concept of the feasibility and safety of PRP treatment to inform larger clinical trials in patients with VLUs. Our preliminary results suggest that PRP delivers a safe and effective treatment for VLU care that can be implemented in primary health-care settings.

Method matters: Experimental evidence for shorter avian sperm in faecal compared to abdominal massage samples

PubMed Central

Cockburn, Glenn; Sánchez-Tójar, Alfredo; Løvlie, Hanne; Schroeder, Julia

2017-01-01

Birds are model organisms in sperm biology. Previous work in zebra finches, suggested that sperm sampled from males' faeces and ejaculates do not differ in size. Here, we tested this assumption in a captive population of house sparrows, Passer domesticus. We compared sperm length in samples from three collection techniques: female dummy, faecal and abdominal massage samples. We found that sperm were significantly shorter in faecal than abdominal massage samples, which was explained by shorter heads and midpieces, but not flagella. This result might indicate that faecal sampled sperm could be less mature than sperm collected by abdominal massage. The female dummy method resulted in an insufficient number of experimental ejaculates because most males ignored it. In light of these results, we recommend using abdominal massage as a preferred method for avian sperm sampling. Where avian sperm cannot be collected by abdominal massage alone, we advise controlling for sperm sampling protocol statistically. PMID:28813481

Frequent insufficient sleep and anxiety and depressive disorders among U.S. community dwellers in 20 states, 2010.

PubMed

Chapman, Daniel P; Presley-Cantrell, Letitia R; Liu, Yong; Perry, Geraldine S; Wheaton, Anne G; Croft, Janet B

2013-04-01

This investigation examined the association of anxiety or depressive disorder and frequent insufficient sleep. Data were obtained from a 2010 telephone survey of a population-based sample of 113,936 adults in 20 states. Respondents were asked how often they did not get enough rest or sleep and if they had ever received a diagnosis of an anxiety or depressive disorder. Frequent insufficient sleep was defined as insufficient rest or sleep during ≥ 14 of the past 30 days. Frequent insufficient sleep was reported by 27.0% of the sample and was significantly more common (p<.05) among respondents who reported both anxiety and depressive disorders (48.6%), depressive disorders only (39.0%), or anxiety only (37.5%) than among adults who reported neither disorder (23.1%). Frequent insufficient sleep is associated with depressive and anxiety disorders, and the odds of the sleep disorder are increased when both classes of psychiatric disorders are diagnosed.

Statistics Clinic

NASA Technical Reports Server (NTRS)

Feiveson, Alan H.; Foy, Millennia; Ploutz-Snyder, Robert; Fiedler, James

2014-01-01

Do you have elevated p-values? Is the data analysis process getting you down? Do you experience anxiety when you need to respond to criticism of statistical methods in your manuscript? You may be suffering from Insufficient Statistical Support Syndrome (ISSS). For symptomatic relief of ISSS, come for a free consultation with JSC biostatisticians at our help desk during the poster sessions at the HRP Investigators Workshop. Get answers to common questions about sample size, missing data, multiple testing, when to trust the results of your analyses and more. Side effects may include sudden loss of statistics anxiety, improved interpretation of your data, and increased confidence in your results.

Researchers' choice of the number and range of levels in experiments affects the resultant variance-accounted-for effect size.

PubMed

Okada, Kensuke; Hoshino, Takahiro

2017-04-01

In psychology, the reporting of variance-accounted-for effect size indices has been recommended and widely accepted through the movement away from null hypothesis significance testing. However, most researchers have paid insufficient attention to the fact that effect sizes depend on the choice of the number of levels and their ranges in experiments. Moreover, the functional form of how and how much this choice affects the resultant effect size has not thus far been studied. We show that the relationship between the population effect size and number and range of levels is given as an explicit function under reasonable assumptions. Counterintuitively, it is found that researchers may affect the resultant effect size to be either double or half simply by suitably choosing the number of levels and their ranges. Through a simulation study, we confirm that this relation also applies to sample effect size indices in much the same way. Therefore, the variance-accounted-for effect size would be substantially affected by the basic research design such as the number of levels. Simple cross-study comparisons and a meta-analysis of variance-accounted-for effect sizes would generally be irrational unless differences in research designs are explicitly considered.

The relationship between insufficient sleep and self-rated health in a nationally representative sample.

PubMed

Geiger, Sarah Dee; Sabanayagam, Charumathi; Shankar, Anoop

2012-01-01

Reduced sleep has been found to be associated with increased risk of diabetes mellitus, hypertension, cardiovascular disease (CVD), and mortality. Self-rated health (SRH) has been shown to be a predictor of CVD and mortality. However, study of the association between insufficient sleep and SRH is limited. We examined participants >18 years of age (n = 377, 160) from a representative, cross-sectional survey (2008 BRFSS). Self-reported insufficient sleep in the previous 30 days was categorized into six groups. The outcome was poor SRH. We calculated odds ratios ((OR) (95% confidence interval (CI)) of increasing categories of insufficient rest/sleep, taking zero days of insufficient sleep as the referent category. We found a positive association between increasing categories of insufficient sleep and poor SRH, independent of relevant covariates. In the multivariable-adjusted model, compared to 0 days insufficient sleep, the OR (95% CI) of poor SRH was 1.03 (0.97-1.10) for 1-6 days, 1.45 (1.34-1.57) for 7-13 days, 2.12 (1.97-2.27) for 14-20 days, 2.32 (2.09-2.58) for 21-29 days, and and 2.71 (2.53-2.90) for 30 days of insufficient sleep in the prior 30 days (P-trend <0.0001). In a nationally representative sample, increasing categories of insufficient sleep were associated with poor SRH.

A Systematic Review of Posttraumatic Growth in Survivors of Interpersonal Violence in Adulthood.

PubMed

Elderton, Anna; Berry, Alexis; Chan, Carmen

2015-10-11

This review critically evaluates the literature on posttraumatic growth in survivors of interpersonal violence, integrating the findings from 12 quantitative and 4 qualitative studies. The following databases were searched using predetermined terms: AMED, EMBASE, MEDLINE, PsycINFO, BNI, CINAHL, and Web of Knowledge. The review's findings suggest that the mean prevalence of growth in interpersonal violence survivors is around 71% (range 58-99%). The highest level of growth was consistently experienced in the "appreciation of life" domain. However, survivors reported growth in the four remaining domains: "personal strength," "new possibilities," "experience of relationships with others," and "outlook on life." The nature of the relationship between growth and distress was inconsistent across studies. A combination of pretrauma, peritrauma, and posttrauma variables were found to be related to the degree of growth survivors experienced. Methodological weaknesses of the quantitative studies included the predominant use of retrospective, cross-sectional, correlational designs, discrepancy in the measurement of growth, insufficient sample sizes for power calculations in five studies and limited external validity. Qualitative findings were limited by sampling methods, insufficient information about interview schedules, the lack of credibility checks, and evidence of reflexivity demonstrated by some studies. Implications for practice, policy, and future research are discussed. © The Author(s) 2015.

Visually Evoked Potential Markers of Concussion History in Patients with Convergence Insufficiency

PubMed Central

Poltavski, Dmitri; Lederer, Paul; Cox, Laurie Kopko

2017-01-01

ABSTRACT Purpose We investigated whether differences in the pattern visual evoked potentials exist between patients with convergence insufficiency and those with convergence insufficiency and a history of concussion using stimuli designed to differentiate between magnocellular (transient) and parvocellular (sustained) neural pathways. Methods Sustained stimuli included 2-rev/s, 85% contrast checkerboard patterns of 1- and 2-degree check sizes, whereas transient stimuli comprised 4-rev/s, 10% contrast vertical sinusoidal gratings with column width of 0.25 and 0.50 cycles/degree. We tested two models: an a priori clinical model based on an assumption of at least a minimal (beyond instrumentation’s margin of error) 2-millisecond lag of transient response latencies behind sustained response latencies in concussed patients and a statistical model derived from the sample data. Results Both models discriminated between concussed and nonconcussed groups significantly above chance (with 76% and 86% accuracy, respectively). In the statistical model, patients with mean vertical sinusoidal grating response latencies greater than 119 milliseconds to 0.25-cycle/degree stimuli (or mean vertical sinusoidal latencies >113 milliseconds to 0.50-cycle/degree stimuli) and mean vertical sinusoidal grating amplitudes of less than 14.75 mV to 0.50-cycle/degree stimuli were classified as having had a history of concussion. The resultant receiver operating characteristic curve for this model had excellent discrimination between the concussed and nonconcussed (area under the curve = 0.857; P < .01) groups with sensitivity of 0.92 and specificity of 0.80. Conclusions The results suggest a promising electrophysiological approach to identifying individuals with convergence insufficiency and a history of concussion. PMID:28609417

The Relationship Between Trait Procrastination, Internet Use, and Psychological Functioning: Results From a Community Sample of German Adolescents.

PubMed

Reinecke, Leonard; Meier, Adrian; Beutel, Manfred E; Schemer, Christian; Stark, Birgit; Wölfling, Klaus; Müller, Kai W

2018-01-01

Adolescents with a strong tendency for irrational task delay (i.e., high trait procrastination) may be particularly prone to use Internet applications simultaneously to other tasks (e.g., during homework) and in an insufficiently controlled fashion. Both Internet multitasking and insufficiently controlled Internet usage may thus amplify the negative mental health implications that have frequently been associated with trait procrastination. The present study explored this role of Internet multitasking and insufficiently controlled Internet use for the relationship between trait procrastination and impaired psychological functioning in a community sample of N = 818 early and middle adolescents. Results from multiple regression analyses indicate that trait procrastination was positively related to Internet multitasking and insufficiently controlled Internet use. Insufficiently controlled Internet use, but not Internet multitasking, was found to partially statistically mediate the association between trait procrastination and adolescents' psychological functioning (i.e., stress, sleep quality, and relationship satisfaction with parents). The study underlines that adolescents with high levels of trait procrastination may have an increased risk for negative outcomes of insufficiently controlled Internet use.

The Relationship Between Trait Procrastination, Internet Use, and Psychological Functioning: Results From a Community Sample of German Adolescents

PubMed Central

Reinecke, Leonard; Meier, Adrian; Beutel, Manfred E.; Schemer, Christian; Stark, Birgit; Wölfling, Klaus; Müller, Kai W.

2018-01-01

Adolescents with a strong tendency for irrational task delay (i.e., high trait procrastination) may be particularly prone to use Internet applications simultaneously to other tasks (e.g., during homework) and in an insufficiently controlled fashion. Both Internet multitasking and insufficiently controlled Internet usage may thus amplify the negative mental health implications that have frequently been associated with trait procrastination. The present study explored this role of Internet multitasking and insufficiently controlled Internet use for the relationship between trait procrastination and impaired psychological functioning in a community sample of N = 818 early and middle adolescents. Results from multiple regression analyses indicate that trait procrastination was positively related to Internet multitasking and insufficiently controlled Internet use. Insufficiently controlled Internet use, but not Internet multitasking, was found to partially statistically mediate the association between trait procrastination and adolescents’ psychological functioning (i.e., stress, sleep quality, and relationship satisfaction with parents). The study underlines that adolescents with high levels of trait procrastination may have an increased risk for negative outcomes of insufficiently controlled Internet use. PMID:29942268

A better understanding of POLDER's cloud droplet size retrieval: impact of cloud horizontal inhomogeneity and directional sampling

NASA Astrophysics Data System (ADS)

Shang, H.; Chen, L.; Bréon, F.-M.; Letu, H.; Li, S.; Wang, Z.; Su, L.

2015-07-01

The principles of the Polarization and Directionality of the Earth's Reflectance (POLDER) cloud droplet size retrieval requires that clouds are horizontally homogeneous. Nevertheless, the retrieval is applied by combining all measurements from an area of 150 km × 150 km to compensate for POLDER's insufficient directional sampling. Using the POLDER-like data simulated with the RT3 model, we investigate the impact of cloud horizontal inhomogeneity and directional sampling on the retrieval, and then analyze which spatial resolution is potentially accessible from the measurements. Case studies show that the sub-scale variability in droplet effective radius (CDR) can mislead both the CDR and effective variance (EV) retrievals. Nevertheless, the sub-scale variations in EV and cloud optical thickness (COT) only influence the EV retrievals and not the CDR estimate. In the directional sampling cases studied, the retrieval is accurate using limited observations and is largely independent of random noise. Several improvements have been made to the original POLDER droplet size retrieval. For example, the measurements in the primary rainbow region (137-145°) are used to ensure accurate large droplet (> 15 μm) retrievals and reduce the uncertainties caused by cloud heterogeneity. We apply the improved method using the POLDER global L1B data for June 2008, the new CDR results are compared with the operational CDRs. The comparison show that the operational CDRs tend to be underestimated for large droplets. The reason is that the cloudbow oscillations in the scattering angle region of 145-165° are weak for cloud fields with CDR > 15 μm. Lastly, a sub-scale retrieval case is analyzed, illustrating that a higher resolution, e.g., 42 km × 42 km, can be used when inverting cloud droplet size parameters from POLDER measurements.

Examination of the Association between Insufficient Sleep and Cardiovascular Disease and Diabetes by Race/Ethnicity.

PubMed

Vishnu, Abhishek; Shankar, Anoop; Kalidindi, Sita

2011-01-01

Background. We examined the association between insufficient rest/sleep and cardiovascular disease or diabetes mellitus separately among non-Hispanic whites, non-Hispanic blacks, Hispanic Americans, and other races in a contemporary sample of US adults. Methods. Multiethnic, nationally representative, cross-sectional survey (2008 BRFSS) participants who were >20 years of age (n = 369, 217; 50% women). Self-reported insufficient rest/sleep in the previous month was categorized into: zero, 1-13, 14-29, and all 30 days. Outcomes were: (1) any CVD, (2) coronary artery disease (CHD), (3) stroke, and (4) diabetes mellitus. Results. Insufficient rest/sleep was found to be positively associated with (1) any CVD, (2) CHD, and (3) stroke among all race-ethnicities. In contrast, insufficient rest/sleep was positively associated with diabetes mellitus in all race-ethnicities except non-Hispanic blacks. The odds ratio of diabetes association with insufficient rest/sleep for all 30 days was 1.37 (1.26-1.48) among non-Hispanic whites, 1.11 (0.90-1.36) among non-Hispanic blacks, 1.88 (1.46-2.42) among Hispanic Americans, and 1.48 (1.10-2.00) among other race/ethnicities. Conclusion. In a multiethnic sample of US adults, perceived insufficient rest/sleep was associated with CVD, among all race-ethnicities. However, the association between insufficient rest/sleep and diabetes mellitus was present among all race-ethnicities except non-Hispanic blacks.

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

Michael Keane; Xiao-Chun Shi; Tong-man Ong

The project staff partnered with Costas Sioutas from the University of Southern California to apply the VACES (Versatile Aerosol Concentration Enhancement System) to a diesel engine test facility at West Virginia University Department of Mechanical Engineering and later the NIOSH Lake Lynn Mine facility. The VACES system was able to allow diesel exhaust particulate matter (DPM) to grow to sufficient particle size to be efficiently collected with the SKC Biosampler impinger device, directly into a suspension of simulated pulmonary surfactant. At the WVU-MAE facility, the concentration of the aerosol was too high to allow efficient use of the VACES concentrationmore » enhancement, although aerosol collection was successful. Collection at the LLL was excellent with the diluted exhaust stream. In excess of 50 samples were collected at the LLL facility, along with matching filter samples, at multiple engine speed and load conditions. Replicate samples were combined and concentration increased using a centrifugal concentrator. Bioassays were negative for all tested samples, but this is believed to be due to insufficient concentration in the final assay suspensions.« less

Joint-linkage mapping and GWAS reveal extensive genetic loci that regulate male inflorescence size in maize

USDA-ARS?s Scientific Manuscript database

Both insufficient and excessive male inflorescence size leads to a reduction in maize yield. Knowledge of the genetic architecture of male inflorescence is essential to achieve the optimum inflorescence size for maize breeding. In this study, we used approximately eight thousand inbreds, including b...

Assessment of Nanoparticle Exposure in Nanosilica Handling Process: Including Characteristics of Nanoparticles Leaking from a Vacuum Cleaner

PubMed Central

KIM, Boowook; KIM, Hyunwook; YU, Il Je

2013-01-01

Nanosilica is one of the most widely used nanomaterials across the world. However, their assessment data on the occupational exposure to nanoparticles is insufficient. The present study performed an exposure monitoring in workplace environments where synthetic powders are prepared using fumed nanosilica. Furthermore, after it was observed during exposure monitoring that nanoparticles were emitted through leakage in a vacuum cleaner (even with a HEPA-filter installed in it), the properties of the leaked nanoparticles were also investigated. Workers were exposed to high-concentration nanosilica emitted into the air while pouring it into a container or transferring the container. The use of a vacuum cleaner with a leak (caused by an inadequate sealing) was found to be the origin of nanosilica dispersion in the indoor air. While the particle size of the nanosilica that emitted into the air (during the handling of nanosilica by a worker) was mostly over 100 nm or several microns (µm) due to the coagulation of particles, the size of nanosilica that leaked out of vacuum cleaner was almost similar to the primary size (mode diameter 11.5 nm). Analysis of area samples resulted in 20% (60% in terms of peak concentration) less than the analysis of the personals sample. PMID:24366536

Assessment of nanoparticle exposure in nanosilica handling process: including characteristics of nanoparticles leaking from a vacuum cleaner.

PubMed

Kim, Boowook; Kim, Hyunwook; Yu, Il Je

2014-01-01

Nanosilica is one of the most widely used nanomaterials across the world. However, their assessment data on the occupational exposure to nanoparticles is insufficient. The present study performed an exposure monitoring in workplace environments where synthetic powders are prepared using fumed nanosilica. Furthermore, after it was observed during exposure monitoring that nanoparticles were emitted through leakage in a vacuum cleaner (even with a HEPA-filter installed in it), the properties of the leaked nanoparticles were also investigated. Workers were exposed to high-concentration nanosilica emitted into the air while pouring it into a container or transferring the container. The use of a vacuum cleaner with a leak (caused by an inadequate sealing) was found to be the origin of nanosilica dispersion in the indoor air. While the particle size of the nanosilica that emitted into the air (during the handling of nanosilica by a worker) was mostly over 100 nm or several microns (µm) due to the coagulation of particles, the size of nanosilica that leaked out of vacuum cleaner was almost similar to the primary size (mode diameter 11.5 nm). Analysis of area samples resulted in 20% (60% in terms of peak concentration) less than the analysis of the personals sample.

Sleep insufficiency and the natural environment: Results from the US Behavioral Risk Factor Surveillance System survey.

PubMed

Grigsby-Toussaint, Diana S; Turi, Kedir N; Krupa, Mark; Williams, Natasha J; Pandi-Perumal, Seithikurippu R; Jean-Louis, Girardin

2015-09-01

Exposure to the natural environment may improve health behaviors and mental health outcomes such as increased levels of physical activity and lower levels of depression associated with sleep quality. Little is known about the relationship between insufficient sleep and the natural environment. To determine whether exposure to attributes of the natural environment (e.g., greenspace) attenuates the likelihood of reporting insufficient sleep among US adults. Multiple logistic regression models were used to explore the association between self-reported days of insufficient sleep (in the past 30days) and access to the natural environment in a multi-ethnic, nationally representative sample (n=255,171) of US adults ≥18years of age enrolled in the 2010 Behavioral Risk Factor Surveillance System. Using 1-to-6days of insufficient sleep as the referent group for all analyses, lower odds of exposure to natural amenities were observed for individuals reporting 21-to-29days (OR=0.843, 95% confidence interval (CI)=0.747, 0.951) of insufficient sleep. In stratified analyses, statistically significant lower odds of exposure to natural amenities were found among men reporting 7-to-13-days (OR=0.911, 95% CI=0.857, 0.968), 21-to-29-days (OR=0.838, 95% CI=0.759, 0.924), and 30-days (OR=0.860, 95% CI=0.784, 0.943) of insufficient sleep. Greenspace access was also protective against insufficient sleep for men and individuals aged 65+. In a representative sample of US adults, access to the natural environment attenuated the likelihood of reporting insufficient sleep, particularly among men. Additional studies are needed to examine the impact of natural environment exposure on sleep insufficiency across various socio-demographic groups. Copyright © 2015 Elsevier Inc. All rights reserved.

Clinical decision making and the expected value of information.

PubMed

Willan, Andrew R

2007-01-01

The results of the HOPE study, a randomized clinical trial, provide strong evidence that 1) ramipril prevents the composite outcome of cardiovascular death, myocardial infarction or stroke in patients who are at high risk of a cardiovascular event and 2) ramipril is cost-effective at a threshold willingness-to-pay of $10,000 to prevent an event of the composite outcome. In this report the concept of the expected value of information is used to determine if the information provided by the HOPE study is sufficient for decision making in the US and Canada. and results Using the cost-effectiveness data from a clinical trial, or from a meta-analysis of several trials, one can determine, based on the number of future patients that would benefit from the health technology under investigation, the expected value of sample information (EVSI) of a future trial as a function of proposed sample size. If the EVSI exceeds the cost for any particular sample size then the current information is insufficient for decision making and a future trial is indicated. If, on the other hand, there is no sample size for which the EVSI exceeds the cost, then there is sufficient information for decision making and no future trial is required. Using the data from the HOPE study these concepts are applied for various assumptions regarding the fixed and variable cost of a future trial and the number of patients who would benefit from ramipril. Expected value of information methods provide a decision-analytic alternative to the standard likelihood methods for assessing the evidence provided by cost-effectiveness data from randomized clinical trials.

Bedtime procrastination: A self-regulation perspective on sleep insufficiency in the general population.

PubMed

Kroese, Floor M; Evers, Catharine; Adriaanse, Marieke A; de Ridder, Denise T D

2016-05-01

Getting insufficient sleep has serious consequences in terms of mental and physical health. The current study is the first to approach insufficient sleep from a self-regulation perspective by investigating the phenomenon of bedtime procrastination: going to bed later than intended, without having external reasons for doing so. Data from a representative sample of Dutch adults (N = 2431) revealed that a large proportion of the general population experiences getting insufficient sleep and regularly goes to bed later than they would like to. Most importantly, a relationship between self-regulation and experienced insufficient sleep was found, which was mediated by bedtime procrastination. © The Author(s) 2014.

Clinical biochemistry laboratory rejection rates due to various types of preanalytical errors.

PubMed

Atay, Aysenur; Demir, Leyla; Cuhadar, Serap; Saglam, Gulcan; Unal, Hulya; Aksun, Saliha; Arslan, Banu; Ozkan, Asuman; Sutcu, Recep

2014-01-01

Preanalytical errors, along the process from the beginning of test requests to the admissions of the specimens to the laboratory, cause the rejection of samples. The aim of this study was to better explain the reasons of rejected samples, regarding to their rates in certain test groups in our laboratory. This preliminary study was designed on the rejected samples in one-year period, based on the rates and types of inappropriateness. Test requests and blood samples of clinical chemistry, immunoassay, hematology, glycated hemoglobin, coagulation and erythrocyte sedimentation rate test units were evaluated. Types of inappropriateness were evaluated as follows: improperly labelled samples, hemolysed, clotted specimen, insufficient volume of specimen and total request errors. A total of 5,183,582 test requests from 1,035,743 blood collection tubes were considered. The total rejection rate was 0.65 %. The rejection rate of coagulation group was significantly higher (2.28%) than the other test groups (P < 0.001) including insufficient volume of specimen error rate as 1.38%. Rejection rates of hemolysis, clotted specimen and insufficient volume of sample error were found to be 8%, 24% and 34%, respectively. Total request errors, particularly, for unintelligible requests were 32% of the total for inpatients. The errors were especially attributable to unintelligible requests of inappropriate test requests, improperly labelled samples for inpatients and blood drawing errors especially due to insufficient volume of specimens in a coagulation test group. Further studies should be performed after corrective and preventive actions to detect a possible decrease in rejecting samples.

Evaluation of Sampling Recommendations From the Influenza Virologic Surveillance Right Size Roadmap for Idaho.

PubMed

Rosenthal, Mariana; Anderson, Katey; Tengelsen, Leslie; Carter, Kris; Hahn, Christine; Ball, Christopher

2017-08-24

The Right Size Roadmap was developed by the Association of Public Health Laboratories and the Centers for Disease Control and Prevention to improve influenza virologic surveillance efficiency. Guidelines were provided to state health departments regarding representativeness and statistical estimates of specimen numbers needed for seasonal influenza situational awareness, rare or novel influenza virus detection, and rare or novel influenza virus investigation. The aim of this study was to compare Roadmap sampling recommendations with Idaho's influenza virologic surveillance to determine implementation feasibility. We calculated the proportion of medically attended influenza-like illness (MA-ILI) from Idaho's influenza-like illness surveillance among outpatients during October 2008 to May 2014, applied data to Roadmap-provided sample size calculators, and compared calculations with actual numbers of specimens tested for influenza by the Idaho Bureau of Laboratories (IBL). We assessed representativeness among patients' tested specimens to census estimates by age, sex, and health district residence. Among outpatients surveilled, Idaho's mean annual proportion of MA-ILI was 2.30% (20,834/905,818) during a 5-year period. Thus, according to Roadmap recommendations, Idaho needs to collect 128 specimens from MA-ILI patients/week for situational awareness, 1496 influenza-positive specimens/week for detection of a rare or novel influenza virus at 0.2% prevalence, and after detection, 478 specimens/week to confirm true prevalence is ≤2% of influenza-positive samples. The mean number of respiratory specimens Idaho tested for influenza/week, excluding the 2009-2010 influenza season, ranged from 6 to 24. Various influenza virus types and subtypes were collected and specimen submission sources were representative in terms of geographic distribution, patient age range and sex, and disease severity. Insufficient numbers of respiratory specimens are submitted to IBL for influenza laboratory testing. Increased specimen submission would facilitate meeting Roadmap sample size recommendations. ©Mariana Rosenthal, Katey Anderson, Leslie Tengelsen, Kris Carter, Christine Hahn, Christopher Ball. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 24.08.2017.

Evaluation of Sampling Recommendations From the Influenza Virologic Surveillance Right Size Roadmap for Idaho

PubMed Central

2017-01-01

Background The Right Size Roadmap was developed by the Association of Public Health Laboratories and the Centers for Disease Control and Prevention to improve influenza virologic surveillance efficiency. Guidelines were provided to state health departments regarding representativeness and statistical estimates of specimen numbers needed for seasonal influenza situational awareness, rare or novel influenza virus detection, and rare or novel influenza virus investigation. Objective The aim of this study was to compare Roadmap sampling recommendations with Idaho’s influenza virologic surveillance to determine implementation feasibility. Methods We calculated the proportion of medically attended influenza-like illness (MA-ILI) from Idaho’s influenza-like illness surveillance among outpatients during October 2008 to May 2014, applied data to Roadmap-provided sample size calculators, and compared calculations with actual numbers of specimens tested for influenza by the Idaho Bureau of Laboratories (IBL). We assessed representativeness among patients’ tested specimens to census estimates by age, sex, and health district residence. Results Among outpatients surveilled, Idaho’s mean annual proportion of MA-ILI was 2.30% (20,834/905,818) during a 5-year period. Thus, according to Roadmap recommendations, Idaho needs to collect 128 specimens from MA-ILI patients/week for situational awareness, 1496 influenza-positive specimens/week for detection of a rare or novel influenza virus at 0.2% prevalence, and after detection, 478 specimens/week to confirm true prevalence is ≤2% of influenza-positive samples. The mean number of respiratory specimens Idaho tested for influenza/week, excluding the 2009-2010 influenza season, ranged from 6 to 24. Various influenza virus types and subtypes were collected and specimen submission sources were representative in terms of geographic distribution, patient age range and sex, and disease severity. Conclusions Insufficient numbers of respiratory specimens are submitted to IBL for influenza laboratory testing. Increased specimen submission would facilitate meeting Roadmap sample size recommendations. PMID:28838883

Predictive accuracy of combined genetic and environmental risk scores.

PubMed

Dudbridge, Frank; Pashayan, Nora; Yang, Jian

2018-02-01

The substantial heritability of most complex diseases suggests that genetic data could provide useful risk prediction. To date the performance of genetic risk scores has fallen short of the potential implied by heritability, but this can be explained by insufficient sample sizes for estimating highly polygenic models. When risk predictors already exist based on environment or lifestyle, two key questions are to what extent can they be improved by adding genetic information, and what is the ultimate potential of combined genetic and environmental risk scores? Here, we extend previous work on the predictive accuracy of polygenic scores to allow for an environmental score that may be correlated with the polygenic score, for example when the environmental factors mediate the genetic risk. We derive common measures of predictive accuracy and improvement as functions of the training sample size, chip heritabilities of disease and environmental score, and genetic correlation between disease and environmental risk factors. We consider simple addition of the two scores and a weighted sum that accounts for their correlation. Using examples from studies of cardiovascular disease and breast cancer, we show that improvements in discrimination are generally small but reasonable degrees of reclassification could be obtained with current sample sizes. Correlation between genetic and environmental scores has only minor effects on numerical results in realistic scenarios. In the longer term, as the accuracy of polygenic scores improves they will come to dominate the predictive accuracy compared to environmental scores. © 2017 WILEY PERIODICALS, INC.

Predictive accuracy of combined genetic and environmental risk scores

PubMed Central

Pashayan, Nora; Yang, Jian

2017-01-01

ABSTRACT The substantial heritability of most complex diseases suggests that genetic data could provide useful risk prediction. To date the performance of genetic risk scores has fallen short of the potential implied by heritability, but this can be explained by insufficient sample sizes for estimating highly polygenic models. When risk predictors already exist based on environment or lifestyle, two key questions are to what extent can they be improved by adding genetic information, and what is the ultimate potential of combined genetic and environmental risk scores? Here, we extend previous work on the predictive accuracy of polygenic scores to allow for an environmental score that may be correlated with the polygenic score, for example when the environmental factors mediate the genetic risk. We derive common measures of predictive accuracy and improvement as functions of the training sample size, chip heritabilities of disease and environmental score, and genetic correlation between disease and environmental risk factors. We consider simple addition of the two scores and a weighted sum that accounts for their correlation. Using examples from studies of cardiovascular disease and breast cancer, we show that improvements in discrimination are generally small but reasonable degrees of reclassification could be obtained with current sample sizes. Correlation between genetic and environmental scores has only minor effects on numerical results in realistic scenarios. In the longer term, as the accuracy of polygenic scores improves they will come to dominate the predictive accuracy compared to environmental scores. PMID:29178508

Problems with sampling desert tortoises: A simulation analysis based on field data

USGS Publications Warehouse

Freilich, J.E.; Camp, R.J.; Duda, J.J.; Karl, A.E.

2005-01-01

The desert tortoise (Gopherus agassizii) was listed as a U.S. threatened species in 1990 based largely on population declines inferred from mark-recapture surveys of 2.59-km2 (1-mi2) plots. Since then, several census methods have been proposed and tested, but all methods still pose logistical or statistical difficulties. We conducted computer simulations using actual tortoise location data from 2 1-mi2 plot surveys in southern California, USA, to identify strengths and weaknesses of current sampling strategies. We considered tortoise population estimates based on these plots as "truth" and then tested various sampling methods based on sampling smaller plots or transect lines passing through the mile squares. Data were analyzed using Schnabel's mark-recapture estimate and program CAPTURE. Experimental subsampling with replacement of the 1-mi2 data using 1-km2 and 0.25-km2 plot boundaries produced data sets of smaller plot sizes, which we compared to estimates from the 1-mi 2 plots. We also tested distance sampling by saturating a 1-mi 2 site with computer simulated transect lines, once again evaluating bias in density estimates. Subsampling estimates from 1-km2 plots did not differ significantly from the estimates derived at 1-mi2. The 0.25-km2 subsamples significantly overestimated population sizes, chiefly because too few recaptures were made. Distance sampling simulations were biased 80% of the time and had high coefficient of variation to density ratios. Furthermore, a prospective power analysis suggested limited ability to detect population declines as high as 50%. We concluded that poor performance and bias of both sampling procedures was driven by insufficient sample size, suggesting that all efforts must be directed to increasing numbers found in order to produce reliable results. Our results suggest that present methods may not be capable of accurately estimating desert tortoise populations.

Maternal arsenic exposure and birth outcomes: A comprehensive review of the epidemiologic literature focused on drinking water

PubMed Central

Bloom, Michael S.; Surdu, Simona; Neamtiu, Iulia A.; Gurzau, Eugen S.

2015-01-01

Inorganic arsenic (iAs) is a human toxicant to which populations may be exposed through consumption of geogenically contaminated groundwater. A growing body of experimental literature corroborates the reproductive toxicity of iAs; however, the results of human studies are inconsistent. Therefore, we conducted a comprehensive review of epidemiologic studies focused on drinking water iAs exposure and birth outcomes to assess the evidence for causality and to make recommendations for future study. We reviewed 18 English language papers assessing birth weight, gestational age, and birth size. Thirteen of the studies were conducted among populations with frequent exposure to high-level groundwater iAs contamination (>10 μg/L) and five studies were conducted in areas without recognized contamination. Most studies comprised small samples and used cross-sectional designs, often with ecologic exposure assessment strategies, although several large prospective investigations and studies with individual-level measurements were also reported. We conclude that: 1) the epidemiologic evidence for an increased risk of low birth weight (<2,500 grams) is insufficient, although there exists limited evidence for birth weight decreases; 2) the evidence for increased preterm delivery is insufficient; and, 3) there exists minimal evidence for decreased birth size. In further investigation of birth weight and size, we recommend incorporation of individual susceptibility measures using appropriate biomarkers, with collection timed to windows of vulnerability and speciated arsenic analysis, as well as consideration of populations exposed primarily to drinking water iAs contamination <10 μg/L. Given the large potential public health impact, additional, high quality epidemiologic studies are necessary to more definitively assess the risk. PMID:24713268

Maternal arsenic exposure and birth outcomes: a comprehensive review of the epidemiologic literature focused on drinking water.

PubMed

Bloom, Michael S; Surdu, Simona; Neamtiu, Iulia A; Gurzau, Eugen S

2014-09-01

Inorganic arsenic (iAs) is a human toxicant to which populations may be exposed through consumption of geogenically contaminated groundwater. A growing body of experimental literature corroborates the reproductive toxicity of iAs; however, the results of human studies are inconsistent. Therefore, we conducted a comprehensive review of epidemiologic studies focused on drinking water iAs exposure and birth outcomes to assess the evidence for causality and to make recommendations for future study. We reviewed 18 English language papers assessing birth weight, gestational age, and birth size. Thirteen of the studies were conducted among populations with frequent exposure to high-level groundwater iAs contamination (>10 μg/L) and five studies were conducted in areas without recognized contamination. Most studies comprised small samples and used cross-sectional designs, often with ecologic exposure assessment strategies, although several large prospective investigations and studies with individual-level measurements were also reported. We conclude that: (1) the epidemiologic evidence for an increased risk of low birth weight (<2500 g) is insufficient, although there exists limited evidence for birth weight decreases; (2) the evidence for increased preterm delivery is insufficient; and, (3) there exists minimal evidence for decreased birth size. In further investigation of birth weight and size, we recommend incorporation of individual susceptibility measures using appropriate biomarkers, with collection timed to windows of vulnerability and speciated arsenic analysis, as well as consideration of populations exposed primarily to drinking water iAs contamination <10 μg/L. Given the large potential public health impact, additional, high quality epidemiologic studies are necessary to more definitively assess the risk. Copyright © 2014 Elsevier GmbH. All rights reserved.

Nutrient Intake Is Insufficient among Senegalese Urban School Children and Adolescents: Results from Two 24 h Recalls in State Primary Schools in Dakar

PubMed Central

Fiorentino, Marion; Landais, Edwige; Bastard, Guillaume; Carriquiry, Alicia; Wieringa, Frank T.; Berger, Jacques

2016-01-01

Due to rapid urbanization and high food prices and in the absence of nutrition programs, school children from urban areas in West Africa often have insufficient and inadequate diet leading to nutrient deficiencies that affect their health and schooling performance. Acute malnutrition and micronutrient deficiencies are prevalent in children from primary state schools of Dakar (Senegal). The objectives of the present study were to assess the overall diet of these children, to report insufficient/excessive energy and nutrient intakes and to investigate association between insufficient nutrient intake and micronutrient deficiencies. Children attending urban state primary schools in the Dakar area were selected through a two-stage random cluster sampling (30 schools × 20 children). Dietary intake data were obtained from two 24 h recalls and blood samples were collected from 545 children (aged 5–17 years, 45% < 10 years, 53% girls) and adjusted for intra-individual variability to estimate nutrient usual intakes. Energy intake was insufficient and unbalanced with insufficient contribution of protein and excessive contribution of fat to global energy intake in one third of the children. Proportions of children with insufficient intake were: 100% for calcium, 100% for folic acid, 79% for vitamin A, 69% for zinc, 53% for vitamin C and 46% for iron. Insufficient iron and protein intake were risk factors for iron deficiency (odds ratio, OR 1.5, 2.2). Insufficient zinc intake and energy intake from protein were risk factors for zinc deficiency (OR 1.8, 3.0, 1.7, 2.9). Insufficient iron and vitamin C intake, and insufficient energy intake from protein were risk factors for marginal vitamin A status (OR 1.8, 1.8, 3.3). To address nutritional deficiencies associated with a diet deficient in energy, protein and micronutrients, nutrition education or school feeding programs are needed in urban primary schools of Senegal. PMID:27775598

Nutrient Intake Is Insufficient among Senegalese Urban School Children and Adolescents: Results from Two 24 h Recalls in State Primary Schools in Dakar.

PubMed

Fiorentino, Marion; Landais, Edwige; Bastard, Guillaume; Carriquiry, Alicia; Wieringa, Frank T; Berger, Jacques

2016-10-20

Due to rapid urbanization and high food prices and in the absence of nutrition programs, school children from urban areas in West Africa often have insufficient and inadequate diet leading to nutrient deficiencies that affect their health and schooling performance. Acute malnutrition and micronutrient deficiencies are prevalent in children from primary state schools of Dakar (Senegal). The objectives of the present study were to assess the overall diet of these children, to report insufficient/excessive energy and nutrient intakes and to investigate association between insufficient nutrient intake and micronutrient deficiencies. Children attending urban state primary schools in the Dakar area were selected through a two-stage random cluster sampling (30 schools × 20 children). Dietary intake data were obtained from two 24 h recalls and blood samples were collected from 545 children (aged 5-17 years, 45% < 10 years, 53% girls) and adjusted for intra-individual variability to estimate nutrient usual intakes. Energy intake was insufficient and unbalanced with insufficient contribution of protein and excessive contribution of fat to global energy intake in one third of the children. Proportions of children with insufficient intake were: 100% for calcium, 100% for folic acid, 79% for vitamin A, 69% for zinc, 53% for vitamin C and 46% for iron. Insufficient iron and protein intake were risk factors for iron deficiency (odds ratio, OR 1.5, 2.2). Insufficient zinc intake and energy intake from protein were risk factors for zinc deficiency (OR 1.8, 3.0, 1.7, 2.9). Insufficient iron and vitamin C intake, and insufficient energy intake from protein were risk factors for marginal vitamin A status (OR 1.8, 1.8, 3.3). To address nutritional deficiencies associated with a diet deficient in energy, protein and micronutrients, nutrition education or school feeding programs are needed in urban primary schools of Senegal.

Vitamin D in corticosteroid-naïve and corticosteroid-treated Duchenne muscular dystrophy: what dose achieves optimal 25(OH) vitamin D levels?

PubMed

Alshaikh, Nahla; Brunklaus, Andreas; Davis, Tracey; Robb, Stephanie A; Quinlivan, Ros; Munot, Pinki; Sarkozy, Anna; Muntoni, Francesco; Manzur, Adnan Y

2016-10-01

Assessment of the efficacy of vitamin D replenishment and maintenance doses required to attain optimal levels in boys with Duchenne muscular dystrophy (DMD). 25(OH)-vitamin D levels and concurrent vitamin D dosage were collected from retrospective case-note review of boys with DMD at the Dubowitz Neuromuscular Centre. Vitamin D levels were stratified as deficient at <25 nmol/L, insufficient at 25-49 nmol/L, adequate at 50-75 nmol/L and optimal at >75 nmol/L. 617 vitamin D samples were available from 197 boys (range 2-18 years)-69% from individuals on corticosteroids. Vitamin D-naïve boys (154 samples) showed deficiency in 28%, insufficiency in 42%, adequate levels in 24% and optimal levels in 6%. The vitamin D-supplemented group (463 samples) was tested while on different maintenance/replenishment doses. Three-month replenishment of daily 3000 IU (23 samples) or 6000 IU (37 samples) achieved optimal levels in 52% and 84%, respectively. 182 samples taken on 400 IU revealed deficiency in 19 (10%), insufficiency in 84 (47%), adequate levels in 67 (37%) and optimal levels in 11 (6%). 97 samples taken on 800 IU showed deficiency in 2 (2%), insufficiency in 17 (17%), adequate levels in 56 (58%) and optimal levels in 22 (23%). 81 samples were on 1000 IU and 14 samples on 1500 IU, with optimal levels in 35 (43%) and 9 (64%), respectively. No toxic level was seen (highest level 230 nmol/L). The prevalence of vitamin D deficiency and insufficiency in DMD is high. A 2-month replenishment regimen of 6000 IU and maintenance regimen of 1000-1500 IU/day was associated with optimal vitamin D levels. These data have important implications for optimising vitamin D dosing in DMD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Injectable silk foams for the treatment of cervical insufficiency

NASA Astrophysics Data System (ADS)

Fournier, Eric P.

Preterm birth is the leading cause of neonatal mortality, resulting in over 4,000 deaths each year. A significant risk factor for preterm birth is cervical insufficiency, the weakening and subsequent deformation of cervical tissue. Cervical insufficiency is both detectable and treatable but current treatments are lacking. The most common approach requires multiple invasive procedures. This work investigates the injection of silk foams, a minimally-invasive method for supporting cervical tissue. Silk offers many advantages for use as a biomaterial including strength, versatility, and biocompatibility. Injectable silk foams will minimize patient discomfort while also providing more targeted and personalized treatment. A battery of mechanical testing was undertaken to determine silk foam response under physiologically relevant loading and environmental conditions. Mechanical testing was paired with analysis of foam morphology and structure that illustrated the effects of injection on pore geometry and size. Biological response to silk foams was evaluated using an in vitro degradation study and subcutaneous in vivo implantation in a mouse model. Results showed that foams exceeded the mechanical requirements for stiffening cervical tissue, although the current injection process limits foam size. Injection was shown to cause measurable but localized foam deformation. This work indicates that silk foams are a feasible treatment option for cervical insufficiency but challenges remain with foam delivery.

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials

PubMed Central

Hagmann, Joseph A.; Le, Son T.; Richter, Curt A.; Seiler, David G.

2016-01-01

Novel electronic materials are often produced for the first time by synthesis processes that yield bulk crystals (in contrast to single crystal thin film synthesis) for the purpose of exploratory materials research. Certain materials pose a challenge wherein the traditional bulk Hall bar device fabrication method is insufficient to produce a measureable device for sample transport measurement, principally because the single crystal size is too small to attach wire leads to the sample in a Hall bar configuration. This can be, for example, because the first batch of a new material synthesized yields very small single crystals or because flakes of samples of one to very few monolayers are desired. In order to enable rapid characterization of materials that may be carried out in parallel with improvements to their growth methodology, a method of device fabrication for very small samples has been devised to permit the characterization of novel materials as soon as a preliminary batch has been produced. A slight variation of this methodology is applicable to producing devices using exfoliated samples of two-dimensional materials such as graphene, hexagonal boron nitride (hBN), and transition metal dichalcogenides (TMDs), as well as multilayer heterostructures of such materials. Here we present detailed protocols for the experimental device fabrication of fragments and flakes of novel materials with micron-sized dimensions onto substrate and subsequent measurement in a commercial superconducting magnet, dry helium close-cycle cryostat magnetotransport system at temperatures down to 0.300 K and magnetic fields up to 12 T. PMID:26863449

Research on the relativity between gene polymorphism and children cardiac insufficiency.

PubMed

He, X-H; Li, C-L; Ling, N; Wang, Q-W; Wang, Z-Z; An, X-J

2017-08-01

We analyzed the relationship between Mink-S27 gene polymorphism and children with cardiac insufficiency. From April 2013 to April 2015, we enrolled 73 cases of children with cardiac insufficiency for this study, and all 73 were placed in the observation group. 76 normal cases were selected for the control group. Restriction fragment length polymorphism (RFLP) was used to make polymorphism analysis of the Mink-S27. Our results showed no significant differences in Mink-S27 genotype and allele distribution in both observation and control groups (p>0.05). In lesion samples collected from children with cardiac insufficiency, we detected significant difference in AA, CC genotype frequency and allele frequency between the observation group and the control group (p< 0.05) (X2 = 15.43, p<0.05; X2  = 16.27, p<0.05). Further studies on samples obtained from both groups revealed certain differences of AA, CC, AC genotype frequency and allele frequency in the observation group. The proportion of homozygote (AA, CC) in children with severe cardiac insufficiency was relatively high. GNAS2 gene polymorphism was associated with the prevalence of cardiac insufficiency in children. And also the patients' condition was correlated to the frequency of different genotypes and alleles.

Critical considerations when planning experimental in vivo studies in dental traumatology.

PubMed

Andreasen, Jens O; Andersson, Lars

2011-08-01

In vivo studies are sometimes needed to understand healing processes after trauma. For several reasons, not the least ethical, such studies have to be carefully planned and important considerations have to be taken into account about suitability of the experimental model, sample size and optimizing the accuracy of the analysis. Several manuscripts of in vivo studies are submitted for publication to Dental Traumatology and rejected because of inadequate design, methodology or insufficient documentation of the results. The authors have substantial experience in experimental in vivo studies of tissue healing in dental traumatology and share their knowledge regarding critical considerations when planning experimental in vivo studies. © 2011 John Wiley & Sons A/S.

Effects of finite size on spin glass dynamics

NASA Astrophysics Data System (ADS)

Sato, Tetsuya; Komatsu, Katsuyoshi

2010-12-01

In spite of comprehensive studies to clarify a variety of interesting phenomena of spin glasses, their understanding has been insufficiently established. To overcome such a problem, fabrication of a mesoscopic spin glass system, whose dynamics can be observed over the entire range to the equilibrium, is useful. In this review the challenges of research that has been performed up to now in this direction and our recent related studies are introduced. We have established to study the spin glass behaviour in terms of droplet picture using nanofabricated mesoscopic samples to some extent, but some problems that should be clarified have been left. Finally, the direction of some new studies is proposed to solve the problems.

Development and validation of a multiplex reaction analyzing eight miniSTRs of the X chromosome for identity and kinship testing with degraded DNA.

PubMed

Castañeda, María; Odriozola, Adrián; Gómez, Javier; Zarrabeitia, María T

2013-07-01

We report the development of an effective system for analyzing X chromosome-linked mini short tandem repeat loci with reduced-size amplicons (less than 220 bp), useful for analyzing highly degraded DNA samples. To generate smaller amplicons, we redesigned primers for eight X-linked microsatellites (DXS7132, DXS10079, DXS10074, DXS10075, DXS6801, DXS6809, DXS6789, and DXS6799) and established efficient conditions for a multiplex PCR system (miniX). The validation tests confirmed that it has good sensitivity, requiring as little as 20 pg of DNA, and performs well with DNA from paraffin-embedded tissues, thus showing potential for improved analysis and identification of highly degraded and/or very limited DNA samples. Consequently, this system may help to solve complex forensic cases, particularly when autosomal markers convey insufficient information.

Systematic review of the cost-effectiveness of sample size maintenance programs in studies involving postal questionnaires reveals insufficient economic information.

PubMed

David, Michael C; Bensink, Mark; Higashi, Hideki; Boyd, Roslyn; Williams, Lesley; Ware, Robert S

2012-10-01

To identify and assess the existing cost-effectiveness evidence for sample size maintenance programs. Articles were identified by searching Cochrane Central Register of Controlled Trials Embase, CINAHL, PubMed, and Web of Science from 1966 to July 2011. Randomized controlled trials in which investigators evaluated program cost-effectiveness in postal questionnaires were eligible for inclusion. Fourteen studies from 13 articles, with 11,165 participants met the inclusion criteria. Thirty-one distinct programs were identified; each incorporated at least one strategy (reminders, incentives, modified questionnaires, or types of postage) aimed at minimizing attrition. Reminders, in the form of replacement questionnaires and cards, were the most commonly used strategies, with 15 and 11 studies reporting their usage, respectively. All strategies improved response, with financial incentives being the most costly. Heterogeneity between studies was too great to allow for meta-analysis of the results. The implementation of strategies such as no-obligation incentives, modified questionnaires, and personalized reply paid postage improved program cost-effectiveness. Analyses of attrition minimization programs need to consider both cost and effect in their evaluation. Copyright © 2012 Elsevier Inc. All rights reserved.

Small sample mediation testing: misplaced confidence in bootstrapped confidence intervals.

PubMed

Koopman, Joel; Howe, Michael; Hollenbeck, John R; Sin, Hock-Peng

2015-01-01

Bootstrapping is an analytical tool commonly used in psychology to test the statistical significance of the indirect effect in mediation models. Bootstrapping proponents have particularly advocated for its use for samples of 20-80 cases. This advocacy has been heeded, especially in the Journal of Applied Psychology, as researchers are increasingly utilizing bootstrapping to test mediation with samples in this range. We discuss reasons to be concerned with this escalation, and in a simulation study focused specifically on this range of sample sizes, we demonstrate not only that bootstrapping has insufficient statistical power to provide a rigorous hypothesis test in most conditions but also that bootstrapping has a tendency to exhibit an inflated Type I error rate. We then extend our simulations to investigate an alternative empirical resampling method as well as a Bayesian approach and demonstrate that they exhibit comparable statistical power to bootstrapping in small samples without the associated inflated Type I error. Implications for researchers testing mediation hypotheses in small samples are presented. For researchers wishing to use these methods in their own research, we have provided R syntax in the online supplemental materials. (c) 2015 APA, all rights reserved.

Impact of cloud horizontal inhomogeneity and directional sampling on the retrieval of cloud droplet size by the POLDER instrument

NASA Astrophysics Data System (ADS)

Shang, H.; Chen, L.; Bréon, F. M.; Letu, H.; Li, S.; Wang, Z.; Su, L.

2015-11-01

The principles of cloud droplet size retrieval via Polarization and Directionality of the Earth's Reflectance (POLDER) requires that clouds be horizontally homogeneous. The retrieval is performed by combining all measurements from an area of 150 km × 150 km to compensate for POLDER's insufficient directional sampling. Using POLDER-like data simulated with the RT3 model, we investigate the impact of cloud horizontal inhomogeneity and directional sampling on the retrieval and analyze which spatial resolution is potentially accessible from the measurements. Case studies show that the sub-grid-scale variability in droplet effective radius (CDR) can significantly reduce valid retrievals and introduce small biases to the CDR (~ 1.5 μm) and effective variance (EV) estimates. Nevertheless, the sub-grid-scale variations in EV and cloud optical thickness (COT) only influence the EV retrievals and not the CDR estimate. In the directional sampling cases studied, the retrieval using limited observations is accurate and is largely free of random noise. Several improvements have been made to the original POLDER droplet size retrieval. For example, measurements in the primary rainbow region (137-145°) are used to ensure retrievals of large droplet (> 15 μm) and to reduce the uncertainties caused by cloud heterogeneity. We apply the improved method using the POLDER global L1B data from June 2008, and the new CDR results are compared with the operational CDRs. The comparison shows that the operational CDRs tend to be underestimated for large droplets because the cloudbow oscillations in the scattering angle region of 145-165° are weak for cloud fields with CDR > 15 μm. Finally, a sub-grid-scale retrieval case demonstrates that a higher resolution, e.g., 42 km × 42 km, can be used when inverting cloud droplet size distribution parameters from POLDER measurements.

Prevalence and Predictors of Functional Vitamin K Insufficiency in Mothers and Newborns in Uganda.

PubMed

Santorino, Data; Siedner, Mark J; Mwanga-Amumpaire, Juliet; Shearer, Martin J; Harrington, Dominic J; Wariyar, Unni

2015-10-16

Vitamin K deficiency bleeding (VKDB) in infancy is a serious but preventable cause of mortality or permanent disability. Lack of epidemiologic data for VKDB in sub-Saharan Africa hinders development and implementation of effective prevention strategies. We used convenience sampling to consecutively enroll mothers delivering in a southwestern Uganda Hospital. We collected socio-demographic and dietary information, and paired samples of maternal venous and neonatal cord blood for the immunoassay of undercarboxylated prothrombin (PIVKA-II), a sensitive marker of functional vitamin K (VK) insufficiency. We used univariable and multivariable logistic regression models to identify predictors of VK insufficiency. We detected PIVKA-II of ≥0.2 AU (Arbitrary Units per mL)/mL (indicative of VK insufficiency) in 33.3% (47/141) of mothers and 66% (93/141) of newborns. Importantly, 22% of babies had PIVKA-II concentrations ≥5.0 AU/mL, likely to be associated with abnormal coagulation indices. We found no significant predictors of newborn VK insufficiency, including infant weight (AOR (adjusted odds ratio) 1.85, 95% CI (confidence interval) 0.15-22.49), gender (AOR 0.54, 95% CI 0.26-1.11), term birth (AOR 0.72, 95% CI 0.20-2.62), maternal VK-rich diet (AOR 1.13, 95% CI 0.55-2.35) or maternal VK insufficiency (AOR 0.99, 95% CI 0.47-2.10). VK insufficiency is common among mothers and newborn babies in southwestern Uganda, which in one fifth of babies nears overt deficiency. Lack of identifiable predictors of newborn VK insufficiency support strategies for universal VK prophylaxis to newborns to prevent VKDB.

Prevalence and Predictors of Functional Vitamin K Insufficiency in Mothers and Newborns in Uganda

PubMed Central

Santorino, Data; Siedner, Mark J.; Mwanga-Amumpaire, Juliet; Shearer, Martin J.; Harrington, Dominic J.; Wariyar, Unni

2015-01-01

Vitamin K deficiency bleeding (VKDB) in infancy is a serious but preventable cause of mortality or permanent disability. Lack of epidemiologic data for VKDB in sub-Saharan Africa hinders development and implementation of effective prevention strategies. We used convenience sampling to consecutively enroll mothers delivering in a southwestern Uganda Hospital. We collected socio-demographic and dietary information, and paired samples of maternal venous and neonatal cord blood for the immunoassay of undercarboxylated prothrombin (PIVKA-II), a sensitive marker of functional vitamin K (VK) insufficiency. We used univariable and multivariable logistic regression models to identify predictors of VK insufficiency. We detected PIVKA-II of ≥0.2 AU (Arbitrary Units per mL)/mL (indicative of VK insufficiency) in 33.3% (47/141) of mothers and 66% (93/141) of newborns. Importantly, 22% of babies had PIVKA-II concentrations ≥5.0 AU/mL, likely to be associated with abnormal coagulation indices. We found no significant predictors of newborn VK insufficiency, including infant weight (AOR (adjusted odds ratio) 1.85, 95% CI (confidence interval) 0.15–22.49), gender (AOR 0.54, 95% CI 0.26–1.11), term birth (AOR 0.72, 95% CI 0.20–2.62), maternal VK-rich diet (AOR 1.13, 95% CI 0.55–2.35) or maternal VK insufficiency (AOR 0.99, 95% CI 0.47–2.10). VK insufficiency is common among mothers and newborn babies in southwestern Uganda, which in one fifth of babies nears overt deficiency. Lack of identifiable predictors of newborn VK insufficiency support strategies for universal VK prophylaxis to newborns to prevent VKDB. PMID:26501317

The Regularities in Insufficient Leisure-Time Physical Activity in Poland.

PubMed

Biernat, Elżbieta; Buchholtz, Sonia

2016-08-08

Insufficient physical activity (PA) has become an increasing risk factor of noncommunicable diseases and an important cause of deaths all over the world. The goal of this paper is to provide an in-depth description of insufficient PA in Poland as well as an examination of some of its correlates. We take advantage of statistical and econometric (logistic regression) analysis on the basis of a representative survey. Out of 3056 respondents, we analyze the 1260 low-PA ones. The household size is more significant than the household life phase, and only several professions increase the odds of insufficient PA. The influence of socioeconomic status and place of residence is most robust. Gender does not significantly influence insufficient PA. Physical inactivity is concentrated among inhabitants of rural areas and town dwellers, with poor educational profile, and limited labor market opportunities. However, even high socioeconomic status does not completely prevent insufficient activity. Groups at the highest risk of inactivity should be covered by promotional actions first. Their aim should mainly be raising the leisure-time physical activity (LTPA) awareness. To start with, primary forms of activity would be walking, Nordic walking and jogging.

ROC curves in clinical chemistry: uses, misuses, and possible solutions.

PubMed

Obuchowski, Nancy A; Lieber, Michael L; Wians, Frank H

2004-07-01

ROC curves have become the standard for describing and comparing the accuracy of diagnostic tests. Not surprisingly, ROC curves are used often by clinical chemists. Our aims were to observe how the accuracy of clinical laboratory diagnostic tests is assessed, compared, and reported in the literature; to identify common problems with the use of ROC curves; and to offer some possible solutions. We reviewed every original work using ROC curves and published in Clinical Chemistry in 2001 or 2002. For each article we recorded phase of the research, prospective or retrospective design, sample size, presence/absence of confidence intervals (CIs), nature of the statistical analysis, and major analysis problems. Of 58 articles, 31% were phase I (exploratory), 50% were phase II (challenge), and 19% were phase III (advanced) studies. The studies increased in sample size from phase I to III and showed a progression in the use of prospective designs. Most phase I studies were powered to assess diagnostic tests with ROC areas >/=0.70. Thirty-eight percent of studies failed to include CIs for diagnostic test accuracy or the CIs were constructed inappropriately. Thirty-three percent of studies provided insufficient analysis for comparing diagnostic tests. Other problems included dichotomization of the gold standard scale and inappropriate analysis of the equivalence of two diagnostic tests. We identify available software and make some suggestions for sample size determination, testing for equivalence in diagnostic accuracy, and alternatives to a dichotomous classification of a continuous-scale gold standard. More methodologic research is needed in areas specific to clinical chemistry.

Collaborative assessment of California spiny lobster population and fishery responses to a marine reserve network.

PubMed

Kay, Matthew C; Lenihan, Hunter S; Guenther, Carla M; Wilson, Jono R; Miller, Christopher J; Shrout, Samuel W

2012-01-01

Assessments of the conservation and fisheries effects of marine reserves typically focus on single reserves where sampling occurs over narrow spatiotemporal scales. A strategy for broadening the collection and interpretation of data is collaborative fisheries research (CFR). Here we report results of a CFR program formed in part to test whether reserves at the Santa Barbara Channel Islands, USA, influenced lobster size and trap yield, and whether abundance changes in reserves led to spillover that influenced trap yield and effort distribution near reserve borders. Industry training of scientists allowed us to sample reserves with fishery relevant metrics that we compared with pre-reserve fishing records, a concurrent port sampling program, fishery effort patterns, the local ecological knowledge (LEK) of fishermen, and fishery-independent visual surveys of lobster abundance. After six years of reserve protection, there was a four- to eightfold increase in trap yield, a 5-10% increase in the mean size (carapace length) of legal sized lobsters, and larger size structure of lobsters trapped inside vs. outside of three replicate reserves. Patterns in trap data were corroborated by visual scuba surveys that indicated a four- to sixfold increase in lobster density inside reserves. Population increases within reserves did not lead to increased trap yields or effort concentrations (fishing the line) immediately outside reserve borders. The absence of these catch and effort trends, which are indicative of spillover, may be due to moderate total mortality (Z = 0.59 for legal sized lobsters outside reserves), which was estimated from analysis of growth and length frequency data collected as part of our CFR program. Spillover at the Channel Islands reserves may be occurring but at levels that are insufficient to influence the fishery dynamics that we measured. Future increases in fishing effort (outside reserves) and lobster biomass (inside reserves) are likely and may lead to increased spillover, and CFR provides an ideal platform for continued assessment of fishery-reserve interactions.

Designing Case-Control Studies: Decisions About the Controls

PubMed Central

Hodge, Susan E.; Subaran, Ryan L.; Weissman, Myrna M.; Fyer, Abby J.

2014-01-01

The authors quantified, first, the effect of misclassified controls (i.e., individuals who are affected with the disease under study but who are classified as controls) on the ability of a case-control study to detect an association between a disease and a genetic marker, and second, the effect of leaving misclassified controls in the study, as opposed to removing them (thus decreasing sample size). The authors developed an informativeness measure of a study’s ability to identify real differences between cases and controls. They then examined this measure’s behavior when there are no misclassified controls, when there are misclassified controls, and when there were misclassified controls but they have been removed from the study. The results show that if, for example, 10% of controls are misclassified, the study’s informativeness is reduced to approximately 81% of what it would have been in a sample with no misclassified controls, whereas if these misclassified controls are removed from the study, the informativeness is only reduced to about 90%, despite the reduced sample size. If 25% are misclassified, those figures become approximately 56% and 75%, respectively. Thus, leaving the misclassified controls in the control sample is worse than removing them altogether. Finally, the authors illustrate how insufficient power is not necessarily circumvented by having an unlimited number of controls. The formulas provided by the authors enable investigators to make rational decisions about removing misclassified controls or leaving them in. PMID:22854929

Do icon arrays help reduce denominator neglect?

PubMed

Garcia-Retamero, Rocio; Galesic, Mirta; Gigerenzer, Gerd

2010-01-01

Denominator neglect is the focus on the number of times a target event has happened (e.g., the number of treated and nontreated patients who die) without considering the overall number of opportunities for it to happen (e.g., the overall number of treated and nontreated patients). In 2 studies, we addressed the effect of denominator neglect in problems involving treatment risk reduction where samples of treated and non-treated patients and the relative risk reduction were of different sizes. We also tested whether using icon arrays helps people take these different sample sizes into account. We especially focused on older adults, who are often more disadvantaged when making decisions about their health. . Study 1 was conducted on a laboratory sample using a within-subjects design; study 2 was conducted on a nonstudent sample interviewed through the Web using a between-subjects design. Accuracy of understanding risk reduction. Participants often paid too much attention to numerators and insufficient attention to denominators when numerical information about treatment risk reduction was provided. Adding icon arrays to the numerical information, however, drew participants' attention to the denominators and helped them make more accurate assessments of treatment risk reduction. Icon arrays were equally helpful to younger and older adults. Building on previous research showing that problems with understanding numerical information often do not reside in the mind but in the representation of the problem, the results show that icon arrays are an effective method of eliminating denominator neglect.

Early morphological and functional changes in pancreas following necrosectomy for acute severe necrotizing pancreatitis.

PubMed

Bavare, Charudatta; Prabhu, Ramkrishna; Supe, Avinash

2004-01-01

Morphological and functional changes in the pancreas after surgical pancreatic necrosectomy have not been studied extensively. To study morphological changes in the pancreas, and exocrine and endocrine pancreatic function following pancreatic necrosectomy. Eighteen adult patients surviving at least one month after pancreatic necrosectomy for acute necrotizing pancreatitis were followed up. Contrast-enhanced computed tomography was done every six months. Stool fat was estimated at 3-month intervals, and need for and response to enzyme supplements were recorded. Blood sugar was measured every fortnight; in patients with hyperglycemia, need for oral hypoglycemic agents or insulin was recorded. Additional pancreatic imaging was done in some cases. Six weeks after surgery, nine of 18 patients had exocrine insufficiency. Thirteen patients developed endocrine insufficiency, including 5 who also had exocrine insufficiency. At the end of the study, 13 patients had endocrine insufficiency and 2 had exocrine insufficiency. Pancreatic size was subnormal in all patients at the end of six months. Pancreatography in three cases did not reveal any ductal abnormality. Necrotizing pancreatitis affects pancreatic exocrine or endocrine function in more than half the patients.

Does Static-99 predict recidivism among older sexual offenders?

PubMed

Hanson, R K

2006-10-01

Static-99 (Hanson & Thornton, 2000) is the most commonly used actuarial risk tool for estimating sexual offender recidivism risk. Recent research has suggested that its methods of accounting for the offenders' ages may be insufficient to capture declines in recidivism risk associated with advanced age. Using data from 8 samples (combined size of 3,425 sexual offenders), the present study found that older offenders had lower Static-99 scores than younger offenders and that Static-99 was moderately accurate in estimating relative recidivism risk in all age groups. Older offenders, however, had lower sexual recidivism rates than would be expected based on their Static-99 risk categories. Consequently, evaluators using Static-99 should considered advanced age in their overall estimate of risk.

The effect of between-breast differences on human milk macronutrients content.

PubMed

Pines, N; Mandel, D; Mimouni, F B; Moran Lev, H; Mangel, L; Lubetzky, R

2016-07-01

Little is known about the effect of maternal handedness and preferential side of breastfeeding upon macronutrients concentration in human milk (HM). We aimed to compare macronutrients content of HM from both breasts, taking into account the self-reported preferential feeding ('dominant') breast, breast size and handedness (right versus left). We tested the null hypothesis that macronutrients content of HM is not affected by breast dominancy, breast size or maternal handedness. Fifty-seven lactating mothers were recruited. HM macronutrients were measured after mid manual expression using infrared transmission spectroscopy. Out of the 57 mothers recruited, 12 were excluded from the analyses because they brought in insufficient samples. Among the 22 who reported a size difference, 16 (73%) had a larger left breast (P<0.001). Approximately a third of women reported no breastfeeding side dominance, a third reported a right dominance and another third reported a left dominance. Breastfeeding side dominance was unaffected by either handedness or breasts size. When size asymmetry was reported (n=22) the dominant side was also the larger breast in 16 (73%) women, the smaller breast in 2 (9%) women, whereas 4 (18%) additional women with asymmetry had no preferential breastfeeding side. There were no statistically significant differences in macronutrients between the right and the left breasts. In multiple stepwise backward regression analysis, fat, carbohydrate, protein and energy contents were unaffected by maternal handedness, breast side dominance or breast size asymmetry. Macronutrients content of mid expression HM is unaffected by maternal handedness, breast size or breast side dominance.

The Diagnostic Accuracy of Incisional Biopsy in the Oral Cavity.

PubMed

Chen, Sara; Forman, Michael; Sadow, Peter M; August, Meredith

2016-05-01

To determine the accuracy of incisional biopsy examination to diagnose oral lesions. This retrospective cohort study was performed to determine the concordance rate between incisional biopsy examination and definitive resection diagnosis for different oral lesions. The study sample was derived from the population of patients who presented to the Department of Oral and Maxillofacial Surgery, Massachusetts General Hospital (Boston, MA) from January 2005 through December 2012. Inclusion criteria were the diagnosis of an oral lesion from an incisional biopsy examination, subsequent diagnosis from the definitive resection of the same lesion, and complete clinical and pathologic patient records. The predictor variables were the origin and size of the lesion. The primary outcome variable was concordance between the provisional incisional biopsy diagnosis and definitive pathologic resection diagnosis. The secondary outcome variable was type of biopsy error for the discordant cases. Incisional biopsy errors were assessed and grouped into 5 categories: 1) sampling error; 2) insufficient tissue for diagnosis; 3) presence of inflammation making diagnosis difficult; 4) artifact; and 5) pathologist discordance. A total of 272 patients met the inclusion criteria. The study sample had a mean age of 47.4 years and 55.7% were women. Of these cases, 242 (88.9%) were concordant when comparing the biopsy and final resection pathology reports. At histologic evaluation, 60.0% of discordant findings were attributed to sampling error, 23.3% to pathologist discrepancy, 13.3% to insufficient tissue provided in the biopsy specimen, and 3.4% to inflammation obscuring diagnosis. Overall, concordant cases had a larger average biopsy volume (1.53 cm(3)) than discordant cases (0.42 cm(3)). The data collected indicate an 88.9% diagnostic concordance with final pathologic results for incisional oral biopsy diagnoses. Sixty percent of discordance was attributed to sampling error when sampled tissue was not representative of the lesion in toto. Multiple-site biopsy specimens and larger-volume samples allowed for a more accurate diagnosis. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Sedimentary Geothermal Feasibility Study: October 2016

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

Augustine, Chad; Zerpa, Luis

The objective of this project is to analyze the feasibility of commercial geothermal projects using numerical reservoir simulation, considering a sedimentary reservoir with low permeability that requires productivity enhancement. A commercial thermal reservoir simulator (STARS, from Computer Modeling Group, CMG) is used in this work for numerical modeling. In the first stage of this project (FY14), a hypothetical numerical reservoir model was developed, and validated against an analytical solution. The following model parameters were considered to obtain an acceptable match between the numerical and analytical solutions: grid block size, time step and reservoir areal dimensions; the latter related to boundarymore » effects on the numerical solution. Systematic model runs showed that insufficient grid sizing generates numerical dispersion that causes the numerical model to underestimate the thermal breakthrough time compared to the analytic model. As grid sizing is decreased, the model results converge on a solution. Likewise, insufficient reservoir model area introduces boundary effects in the numerical solution that cause the model results to differ from the analytical solution.« less

Filling in the Gaps: Xenoliths in Meteorites are Samples of "Missing" Asteroid Lithologies

NASA Technical Reports Server (NTRS)

Zolensky, Mike

2016-01-01

We know that the stones that fall to earth as meteorites are not representative of the full diversity of small solar system bodies, because of the peculiarities of the dynamical processes that send material into Earth-crossing paths [1] which result in severe selection biases. Thus, the bulk of the meteorites that fall are insufficient to understand the full range of early solar system processes. However, the situation is different for pebble- and smaller-sized objects that stream past the giant planets and asteroid belts into the inner solar system in a representative manner. Thus, micrometeorites and interplanetary dust particles have been exploited to permit study of objects that do not provide meteorites to earth. However, there is another population of materials that sample a larger range of small solar system bodies, but which have received little attention - pebble-sized foreign clasts in meteorites (also called xenoliths, dark inclusions, clasts, etc.). Unfortunately, most previous studies of these clasts have been misleading, in that these objects have simply been identified as pieces of CM or CI chondrites. In our work we have found this to be generally erroneous, and that CM and especially CI clasts are actually rather rare. We therefore test the hypothesis that these clasts sample the full range of small solar system bodies. We have located and obtained samples of clasts in 81 different meteorites, and have begun a thorough characterization of the bulk compositions, mineralogies, petrographies, and organic compositions of this unique sample set. In addition to the standard e-beam analyses, recent advances in technology now permit us to measure bulk O isotopic compositions, and major- though trace-element compositions of the sub-mm-sized discrete clasts. Detailed characterization of these clasts permit us to explore the full range of mineralogical and petrologic processes in the early solar system, including the nature of fluids in the Kuiper belt and the outer main asteroid belt, as revealed by the mineralogy of secondary phases.

Sleep Duration and Waist Circumference in Adults: A Meta-Analysis.

PubMed

Sperry, Susan D; Scully, Iiona D; Gramzow, Richard H; Jorgensen, Randall S

2015-08-01

Previous research has demonstrated a relation between insufficient sleep and overall obesity. Waist circumference (WC), a measure of central adiposity, has been demonstrated to improve prediction of health risk. However, recent research on the relation of insufficient sleep duration to WC in adults has yielded inconsistent findings. To assess the magnitude and the consistency of the relation of insufficient sleep and WC. A systematic search of Internet and research databases using Google Scholar, Medline, PubMed, and PsycINFO through July 2013 was conducted. All articles in English with adult human subjects that included measurements of WC and sleep duration were reviewed. A random effects meta-analysis and regression analyses were performed. Heterogeneity and publication bias were checked. Results are expressed as Pearson correlations (r; 95% confidence interval). Of 1,376 articles, 30 met inclusion criteria and 21 studies (22 samples for a total of 56,259 participants) provided sufficient data for meta-analysis. Results showed a significant negative relation between sleep duration and WC (r = -0.10, P < 0.0001) with significant heterogeneity related to sleep comparison method. Potential moderators of the relation between sleep duration and WC were not significant. Funnel plots showed no indication of publication bias. In addition, a fail-safe N calculation indicated that 418 studies with null effects would be necessary to bring the overall mean effect size to a trivial value of r = -0.005. Internationally, cross-sectional studies demonstrate a significant negative relation between sleep duration and waist circumference, indicating shorter sleep durations covary with central adiposity. Future research should include prospective studies. © 2015 Associated Professional Sleep Societies, LLC.

The importance of tree size and fecundity for wind dispersal of big-leaf mahogany

Treesearch

Julian M. Norghauer; Charles A. Nock; James Grogan

2011-01-01

Seed dispersal by wind is a critical yet poorly understood process in tropical forest trees. How tree size and fecundity affect this process at the population level remains largely unknown because of insufficient replication across adults. We measured seed dispersal by the endangered neotropical timber species big-leaf mahogany (Swietenia macrophylla King, Meliaceae)...

Size-exclusion chromatography for the determination of the boiling point distribution of high-boiling petroleum fractions.

PubMed

Boczkaj, Grzegorz; Przyjazny, Andrzej; Kamiński, Marian

2015-03-01

The paper describes a new procedure for the determination of boiling point distribution of high-boiling petroleum fractions using size-exclusion chromatography with refractive index detection. Thus far, the determination of boiling range distribution by chromatography has been accomplished using simulated distillation with gas chromatography with flame ionization detection. This study revealed that in spite of substantial differences in the separation mechanism and the detection mode, the size-exclusion chromatography technique yields similar results for the determination of boiling point distribution compared with simulated distillation and novel empty column gas chromatography. The developed procedure using size-exclusion chromatography has a substantial applicability, especially for the determination of exact final boiling point values for high-boiling mixtures, for which a standard high-temperature simulated distillation would have to be used. In this case, the precision of final boiling point determination is low due to the high final temperatures of the gas chromatograph oven and an insufficient thermal stability of both the gas chromatography stationary phase and the sample. Additionally, the use of high-performance liquid chromatography detectors more sensitive than refractive index detection allows a lower detection limit for high-molar-mass aromatic compounds, and thus increases the sensitivity of final boiling point determination. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Predicting the proportion of full-thickness involvement for any given burn size based on burn resuscitation volumes.

PubMed

Liu, Nehemiah T; Salinas, José; Fenrich, Craig A; Serio-Melvin, Maria L; Kramer, George C; Driscoll, Ian R; Schreiber, Martin A; Cancio, Leopoldo C; Chung, Kevin K

2016-11-01

The depth of burn has been an important factor often overlooked when estimating the total resuscitation fluid needed for early burn care. The goal of this study was to determine the degree to which full-thickness (FT) involvement affected overall 24-hour burn resuscitation volumes. We performed a retrospective review of patients admitted to our burn intensive care unit from December 2007 to April 2013, with significant burns that required resuscitation using our computerized decision support system for burn fluid resuscitation. We defined the degree of FT involvement as FT Index (FTI; percentage of FT injury/percentage of total body surface area (TBSA) burned [%FT / %TBSA]) and compared variables on actual 24-hour fluid resuscitation volumes overall as well as for any given burn size. A total of 203 patients admitted to our burn center during the study period were included in the analysis. Mean age and weight were 47 ± 19 years and 87 ± 18 kg, respectively. Mean %TBSA was 41 ± 20 with a mean %FT of 18 ± 24. As %TBSA, %FT, and FTI increased, so did actual 24-hour fluid resuscitation volumes (mL/kg). However, increase in FTI did not result in increased volume indexed to burn size (mL/kg per %TBSA). This was true even when patients with inhalation injury were excluded. Further investigation revealed that as %TBSA increased, %FT increased nonlinearly (quadratic polynomial) (R = 0.994). Total burn size and FT burn size were both highly correlated with increased 24-hour fluid resuscitation volumes. However, FTI did not correlate with a corresponding increase in resuscitation volumes for any given burn size, even when patients with inhalation injury were excluded. Thus, there are insufficient data to presume that those who receive more volume at any given burn size are likely to be mostly full thickness or vice versa. This was influenced by a relatively low sample size at each 10%TBSA increment and larger burn sizes disproportionately having more FT burns. A more robust sample size may elucidate this relationship better. Therapeutic/care management study, level IV.

High prevalence of vitamin D insufficiency and its association with obesity and metabolic syndrome among Malay adults in Kuala Lumpur, Malaysia.

PubMed

Moy, Foong-Ming; Bulgiba, Awang

2011-09-27

Vitamin D status, as indicated by 25-hydroxyvitamin D is inversely associated with adiposity, glucose homeostasis, lipid profiles, and blood pressure along with its classic role in calcium homeostasis and bone metabolism. It is also shown to be inversely associated with metabolic syndrome and cardiovascular diseases in western populations. However, evidence from the Asian population is limited. Therefore, we aim to study the prevalence of vitamin D insufficiency (< 50 nmol/L) and the association of 25-hydroxyvitamin D with metabolic risk factors among an existing Malay cohort in Kuala Lumpur. This is an analytical cross sectional study. A total of 380 subjects were sampled and their vitamins D status (25-hydroxyvitamin D), fasting blood glucose, full lipid profile were assessed using venous blood. Systolic and diastolic blood pressure, weight, height and waist circumference were measured following standard protocols. Socio-demographic data such as sex, age, smoking status etc were also collected. Data was analysed using t-test, chi-square test, General Linear Model and multiple logistic regression. Females made up 58% of the sample. The mean age of respondents was 48.5 (SD 5.2) years. Females had significantly lower mean Vitamin D levels (36.2; 95% CI: 34.5, 38.0 nmol/L) compared to males (56.2; 95% CI: 53.2, 59.2 nmol/L). Approximately 41% and 87% of males and females respectively had insufficient (< 50 nmol/L) levels of 25-hydroxyvitamin D (p < 0.001). The prevalence of Metabolic Syndrome for the whole sample was 38.4 (95% CI: 33.5, 43.3)%. In the multivariate model (adjusted for age, sex, abdominal obesity, HDL-cholesterol, diastolic blood pressure), insufficient Vitamin D status was significantly associated with 1-year age increments (OR: 0.93; 95% CI: 0.88, 0.98), being female (OR: 8.68; 95% CI: 5.08, 14.83) and abdominal obesity (OR: 2.57; 95% CI: 1.51, 4.39). Respondents with insufficient vitamin D were found to have higher odds of having Metabolic Syndrome (OR: 1.73; 95% CI: 1.02, 2.92) after adjusting for age and sex. Our results highlight the high prevalence of vitamin D insufficiency among Malay adults in Kuala Lumpur. Vitamin D insufficiency is independently associated with younger age, female sex and greater abdominal obesity. Vitamin D insufficiency is also associated with Metabolic Syndrome.

Social and behavioral predictors of insufficient sleep among African Americans and Caucasians.

PubMed

Williams, Natasha J; Grandner, Michael A; Wallace, Douglas M; Cuffee, Yendelela; Airhihenbuwa, Collins; Okuyemi, Kolawole; Ogedegbe, Gbenga; Jean-Louis, Girardin

2016-02-01

Few studies have examined the social and behavioral predictors of insufficient sleep. To assess the social and behavioral predictors of insufficient sleep in the U.S. Data from the 2009 Behavioral Risk Factor Surveillance System (BRFSS) were analyzed. Telephone interviews were conducted in six representative states that completed the optional sleep module. A total of 31,059 respondents were included in the present analysis. BRFSS-provided weights were applied to analyses to adjust for the use of complex design. The mean age for the sample was 56 ± 16 years, with 63% of the sample being female; 88% identified as non-Hispanic white and 12% identified as non-Hispanic black; 42% were not married and 8% did not have a high school degree. The prevalence of insufficient sleep (<7 hours) was 37%. Multivariate-adjusted logistic regression revealed associations of four important factors with insufficient sleep, which were: working more than 40 hours per week [OR = 1.65, p < 0.001, 95% CI = 1.65-1.66], black race/ethnicity [OR = 1.37, p < 0.001, 95% CI = 1.37-1.38], history of heart disease [OR = 1.26, p < 0.001, 95% CI = 1.25-1.28], care-giving to family/friends [OR = 1.50, p < 0.001, 95% CI = 1.49-1.51], and lack of social and emotional support [OR = 1.24, p < 0.001, 95% CI = 1. 23-1.25]. Social and behavioral predictors of health uniquely contribute to the report of insufficient sleep and should be considered when developing programs to increase awareness of the adverse effects of insufficient sleep. Copyright © 2015 Elsevier B.V. All rights reserved.

Is Food Insufficiency Associated with Health Status and Health Care Utilization Among Adults with Diabetes?

PubMed Central

Nelson, Karin; Cunningham, William; Andersen, Ron; Harrison, Gail; Gelberg, Lillian

2001-01-01

OBJECTIVES Preliminary studies have shown that among adults with diabetes, food insufficiency has adverse health consequences, including hypoglycemic episodes and increased need for health care services. The purpose of this study was to determine the prevalence of food insufficiency and to describe the association of food insufficiency with health status and health care utilization in a national sample of adults with diabetes. METHODS We analyzed data from adults with diabetes (n = 1,503) interviewed in the Third National Health and Nutrition Examination Survey. Bivariate and multivariate analyses were used to examine the relationship of food insufficiency to self-reported health status and health care utilization. RESULTS Six percent of adults with diabetes reported food insufficiency, representing more than 568,600 persons nationally (95% confidence interval, 368,400 to 768,800). Food insufficiency was more common among those with incomes below the federal poverty level (17% vs 4%, P≤.001). Adults with diabetes who were food insufficient were more likely to report fair or poor health status than those who were not (63% vs 43%; odds ratio, 2.2; P =.05). In a multivariate analysis, fair or poor health status was independently associated with poverty, nonwhite race, low educational achievement, and number of chronic diseases, but not with food insufficiency. Diabetic adults who were food insufficient reported more physician encounters, either in clinic or by phone, than those who were food secure (12 vs 7, P <.05). In a multivariate linear regression, food insufficiency remained independently associated with increased physician utilization among adults with diabetes. There was no association between food insufficiency and hospitalization in bivariate analysis. CONCLUSIONS Food insufficiency is relatively common among low-income adults with diabetes and was associated with higher physician utilization. PMID:11422638

Branching, flowering and fruiting of Jatropha curcas treated with ethephon or benzyladenine and gibberellins.

PubMed

Costa, Anne P; Vendrame, Wagner; Nietsche, Sílvia; Crane, Jonathan; Moore, Kimberly; Schaffer, Bruce

2016-05-31

Jatropha curcas L. has been identified for biofuel production but it presents limited commercial yields due to limited branching and a lack of yield uniformity. The objective of this study was to evaluate the effects of single application of ethephon or a combination of 6-benzyladenine (BA) with gibberellic acid isomers A4 and A7 (GA4+7) on branch induction, flowering and fruit production in jatropha plants with and without leaves. Plants with and without leaves showed differences for growth and reproductive variables. For all variables except inflorescence set, there were no significant statistical interactions between the presence of leaves and plant growth regulators concentration. The total number of flowers per inflorescence was reduced as ethephon concentration was increased. As BA + GA4 +7 concentration increased, seed dry weight increased. Thus, ethephon and BA + GA4 +7 applications appeared to affect flowering and seed production to a greater extent than branching. The inability to discern significant treatment effects for most variables might have been due to the large variability within plant populations studied and thus resulting in an insufficient sample size. Therefore, data collected from this study were used for statistical estimations of sample sizes to provide a reference for future studies.

Surveillance for transmissible spongiform encephalopathy in scavengers of white-tailed deer carcasses in the chronic wasting disease area of wisconsin

USGS Publications Warehouse

Jennelle, C.S.; Samuel, M.D.; Nolden, C.A.; Keane, D.P.; Barr, D.J.; Johnson, Chad; Vanderloo, J.P.; Aiken, Judd M.; Hamir, A.N.; Hoover, E.A.

2009-01-01

Chronic wasting disease (CWD), a class of neurodegenerative transmissible spongiform encephalopathies (TSE) occurring in cervids, is found in a number of states and provinces across North America. Misfolded prions, the infectious agents of CWD, are deposited in the environment via carcass remains and excreta, and pose a threat of cross-species transmission. In this study tissues were tested from 812 representative mammalian scavengers, collected in the CWD-affected area of Wisconsin, for TSE infection using the IDEXX HerdChek enzyme-linked immunosorbent assay (ELISA). Only four of the collected mammals tested positive using the ELISA, but these were negative when tested by Western blot. While our sample sizes permitted high probabilities of detecting TSE assuming 1% population prevalence in several common scavengers (93%, 87%, and 87% for raccoons, opossums, and coyotes, respectively), insufficient sample sizes for other species precluded similar conclusions. One cannot rule out successful cross-species TSE transmission to scavengers, but the results suggest that such transmission is not frequent in the CWD-affected area of Wisconsin. The need for further surveillance of scavenger species, especially those known to be susceptible to TSE (e.g., cat, American mink, raccoon), is highlighted in both a field and laboratory setting.

Comparison of global versus Asian clinical trial strategies supportive of registration of drugs in Japan.

PubMed

Shirotani, Mari; Kurokawa, Tatsuo; Chiba, Koji

2014-07-01

The number of worldwide and Asian multiregional clinical trials (MRCTs) submitted for Japanese New Drug Applications increased markedly between 2009 and 2013, with an increasing number performed for simultaneously submission in the USA, EU, and Japan. Asian studies accounted for 32% of MRCTs (14/44 studies) and had comparatively small sample sizes (<500 subjects). Moreover, the number of Japanese subjects in Asian studies was 2.1- to 13.4-fold larger than the sample size estimated using the method described in Japanese MRCT guidelines, whereas the ratio for worldwide studies was 0.05- to 4.9-fold. Before the introduction of this guidelines, bridging or domestic clinical development strategies were used as the regional development strategy in accordance with ICH E5 guidelines. The results presented herein suggest that Asian studies were conducted when the drug had already been approved in the US/EU, when phase 3 clinical trials were not be planned in the USA/EU, when there was insufficient knowledge of ethnic differences in drug efficacy and safety, or when Caucasian data could not be extrapolated to the Japanese population. New strategies with Asian studies including the Japanese population could be conducted instead of Japanese domestic development strategy. © 2014, The American College of Clinical Pharmacology.

Improvements for retrieval of cloud droplet size by the POLDER instrument

NASA Astrophysics Data System (ADS)

Shang, H.; Husi, L.; Bréon, F. M.; Ma, R.; Chen, L.; Wang, Z.

2017-12-01

The principles of cloud droplet size retrieval via Polarization and Directionality of the Earth's Reflectance (POLDER) requires that clouds be horizontally homogeneous. The retrieval is performed by combining all measurements from an area of 150 km × 150 km to compensate for POLDER's insufficient directional sampling. Using POLDER-like data simulated with the RT3 model, we investigate the impact of cloud horizontal inhomogeneity and directional sampling on the retrieval and analyze which spatial resolution is potentially accessible from the measurements. Case studies show that the sub-grid-scale variability in droplet effective radius (CDR) can significantly reduce valid retrievals and introduce small biases to the CDR ( 1.5µm) and effective variance (EV) estimates. Nevertheless, the sub-grid-scale variations in EV and cloud optical thickness (COT) only influence the EV retrievals and not the CDR estimate. In the directional sampling cases studied, the retrieval using limited observations is accurate and is largely free of random noise. Several improvements have been made to the original POLDER droplet size retrieval. For example, measurements in the primary rainbow region (137-145°) are used to ensure retrievals of large droplet (>15 µm) and to reduce the uncertainties caused by cloud heterogeneity. A premium resoltion of 0.8° is determined by considering successful retrievals and cloud horizontal homogeneity. The improved algorithm is applied to measurements of POLDER in 2008, and we further compared our retrievals with cloud effective radii estimations of Moderate Resolution Imaging Spectroradiometer (MODIS). The results indicate that in global scale, the cloud effective radii and effective variance is larger in the central ocean than inland and coast areas. Over heavy polluted regions, the cloud droplets has small effective radii and narraw distribution due to the influence of aerosol particles.

Laser-driven hydrothermal process studied with excimer laser pulses

NASA Astrophysics Data System (ADS)

Mariella, Raymond; Rubenchik, Alexander; Fong, Erika; Norton, Mary; Hollingsworth, William; Clarkson, James; Johnsen, Howard; Osborn, David L.

2017-08-01

Previously, we discovered [Mariella et al., J. Appl. Phys. 114, 014904 (2013)] that modest-fluence/modest-intensity 351-nm laser pulses, with insufficient fluence/intensity to ablate rock, mineral, or concrete samples via surface vaporization, still removed the surface material from water-submerged target samples with confinement of the removed material, and then dispersed at least some of the removed material into the water as a long-lived suspension of nanoparticles. We called this new process, which appears to include the generation of larger colorless particles, "laser-driven hydrothermal processing" (LDHP) [Mariella et al., J. Appl. Phys. 114, 014904 (2013)]. We, now, report that we have studied this process using 248-nm and 193-nm laser light on submerged concrete, quartzite, and obsidian, and, even though light at these wavelengths is more strongly absorbed than at 351 nm, we found that the overall efficiency of LDHP, in terms of the mass of the target removed per Joule of laser-pulse energy, is lower with 248-nm and 193-nm laser pulses than with 351-nm laser pulses. Given that stronger absorption creates higher peak surface temperatures for comparable laser fluence and intensity, it was surprising to observe reduced efficiencies for material removal. We also measured the nascent particle-size distributions that LDHP creates in the submerging water and found that they do not display the long tail towards larger particle sizes that we had observed when there had been a multi-week delay between experiments and the date of measuring the size distributions. This is consistent with transient dissolution of the solid surface, followed by diffusion-limited kinetics of nucleation and growth of particles from the resulting thin layer of supersaturated solution at the sample surface.

Histology of the pharyngeal constrictor muscle in 22q11.2 deletion syndrome and non-syndromic children with velopharyngeal insufficiency.

PubMed

Widdershoven, Josine C C; Spruijt, Nicole E; Spliet, Wim G M; Breugem, Corstiaan C; Kon, Moshe; Mink van der Molen, Aebele B

2011-01-01

Plastic surgeons aim to correct velopharyngeal insufficiency manifest by hypernasal speech with a velopharyngoplasty. The functional outcome has been reported to be worse in patients with 22q11.2 deletion syndrome than in patients without the syndrome. A possible explanation is the hypotonia that is often present as part of the syndrome. To confirm a myogenic component of the etiology of velopharyngeal insufficiency in children with 22q11.2 deletion syndrome, specimens of the pharyngeal constrictor muscle were taken from children with and without the syndrome. Histologic properties were compared between the groups. Specimens from the two groups did not differ regarding the presence of increased perimysial or endomysial space, fiber grouping by size or type, internalized nuclei, the percentage type I fibers, or the diameters of type I and type II fibers. In conclusion, a myogenic component of the etiology of velopharyngeal insufficiency in children with 22q11.2 deletion syndrome could not be confirmed.

Histology of the Pharyngeal Constrictor Muscle in 22q11.2 Deletion Syndrome and Non-Syndromic Children with Velopharyngeal Insufficiency

PubMed Central

Widdershoven, Josine C. C.; Spruijt, Nicole E.; Spliet, Wim G. M.; Breugem, Corstiaan C.; Kon, Moshe; Mink van der Molen, Aebele B.

2011-01-01

Plastic surgeons aim to correct velopharyngeal insufficiency manifest by hypernasal speech with a velopharyngoplasty. The functional outcome has been reported to be worse in patients with 22q11.2 deletion syndrome than in patients without the syndrome. A possible explanation is the hypotonia that is often present as part of the syndrome. To confirm a myogenic component of the etiology of velopharyngeal insufficiency in children with 22q11.2 deletion syndrome, specimens of the pharyngeal constrictor muscle were taken from children with and without the syndrome. Histologic properties were compared between the groups. Specimens from the two groups did not differ regarding the presence of increased perimysial or endomysial space, fiber grouping by size or type, internalized nuclei, the percentage type I fibers, or the diameters of type I and type II fibers. In conclusion, a myogenic component of the etiology of velopharyngeal insufficiency in children with 22q11.2 deletion syndrome could not be confirmed. PMID:21738760

Food insufficiency, housing and health-related quality of life: results from the Positive Spaces, Healthy Places study.

PubMed

Choi, Stephanie K Y; Fielden, Sarah; Globerman, Jason; Koornstra, J J Jay; Hambly, Keith; Walker, Glen; Sobota, Michael; O'Brien-Teengs, Doe; Watson, James; Bekele, Tsegaye; Greene, Saara; Tucker, Ruthann; Hwang, Stephen W; Rourke, Sean B; Healthy Places Team, The Positive Spaces

2015-01-01

Studies of people living with HIV who are homeless or unstably housed show a high prevalence of food insufficiency (>50%) and associated poor health outcomes; however, most evidence is in the form of cross-sectional studies. To better understand this issue, we conducted a longitudinal study to examine the impact of food insufficiency and housing instability on overall physical and mental health-related quality of life (HRQoL) among people living with HIV in Ontario. Six hundred and two adults living with HIV were enrolled in the Positive Spaces, Healthy Places study and followed from 2006 to 2009. Interviewer-administered questionnaires were used, and generalized linear mixed-effects models constructed to examine longitudinal associations between food insufficiency, housing instability and physical and mental HRQoL. At baseline, 57% of participants were classified as food insufficient. After adjusting for potential confounders, longitudinal analyses revealed a significant, negative association between food insufficiency and physical and mental HRQoL outcomes, respectively [effect size (ES) with 95% confidence interval (CI): (ES = -2.1, CI = -3.9,-0.3); (ES = -3.5, CI = -6.1,-1.5)]. Furthermore, difficulties meeting housing costs were shown to have additional negative impacts on mental HRQoL. Food insufficiency is highly prevalent among people living with HIV in Ontario, particularly for those with unstable housing. This vulnerable group of individuals is in urgent need of changes to current housing programmes, services and policies, as well as careful consideration of their unmet nutritional needs.

Appraisal of jump distributions in ensemble-based sampling algorithms

NASA Astrophysics Data System (ADS)

Dejanic, Sanda; Scheidegger, Andreas; Rieckermann, Jörg; Albert, Carlo

2017-04-01

Sampling Bayesian posteriors of model parameters is often required for making model-based probabilistic predictions. For complex environmental models, standard Monte Carlo Markov Chain (MCMC) methods are often infeasible because they require too many sequential model runs. Therefore, we focused on ensemble methods that use many Markov chains in parallel, since they can be run on modern cluster architectures. Little is known about how to choose the best performing sampler, for a given application. A poor choice can lead to an inappropriate representation of posterior knowledge. We assessed two different jump moves, the stretch and the differential evolution move, underlying, respectively, the software packages EMCEE and DREAM, which are popular in different scientific communities. For the assessment, we used analytical posteriors with features as they often occur in real posteriors, namely high dimensionality, strong non-linear correlations or multimodality. For posteriors with non-linear features, standard convergence diagnostics based on sample means can be insufficient. Therefore, we resorted to an entropy-based convergence measure. We assessed the samplers by means of their convergence speed, robustness and effective sample sizes. For posteriors with strongly non-linear features, we found that the stretch move outperforms the differential evolution move, w.r.t. all three aspects.

Characterization and quantitation of polyolefin microplastics in personal-care products using high-temperature gel-permeation chromatography.

PubMed

Hintersteiner, Ingrid; Himmelsbach, Markus; Buchberger, Wolfgang W

2015-02-01

In recent years, the development of reliable methods for the quantitation of microplastics in different samples, including evaluating the particles' adverse effects in the marine environment, has become a great concern. Because polyolefins are the most prevalent type of polymer in personal-care products containing microplastics, this study presents a novel approach for their quantitation. The method is suitable for aqueous and hydrocarbon-based products, and includes a rapid sample clean-up involving twofold density separation and a subsequent quantitation with high-temperature gel-permeation chromatography. In contrast with previous procedures, both errors caused by weighing after insufficient separation of plastics and matrix and time-consuming visual sorting are avoided. In addition to reliable quantitative results, in this investigation a comprehensive characterization of the polymer particles isolated from the product matrix, covering size, shape, molecular weight distribution and stabilization, is provided. Results for seven different personal-care products are presented. Recoveries of this method were in the range of 92-96 %.

Vitamin D deficiency and insufficiency among patients with prostate cancer

PubMed Central

Trump, Donald L.; Chadha, Manpreet K.; Sunga, Annette Y.; Fakih, Marwan G.; Ashraf, Umeer; Silliman, Carrie G.; Hollis, Bruce W.; Nesline, Mary K.; Tian, Lili; Tan, Wei; Johnson, Candace S.

2009-01-01

Objective To assess the frequency of vitamin D deficiency among men with prostate cancer, as considerable epidemiological, in vitro, in vivo and clinical data support an association between vitamin D deficiency and prostate cancer outcome. Patients, subjects and methods The study included 120 ambulatory men with recurrent prostate cancer and 50 with clinically localized prostate cancer who were evaluated and serum samples assayed for 25-OH vitamin D levels. Then 100 controls (both sexes), matched for age and season of serum sample, were chosen from a prospective serum banking protocol. The relationship between age, body mass index, disease stage, Eastern Cooperative Oncology Group performance status, season and previous therapy on vitamin D status were evaluated using univariate and multivariate analyses. Results The mean 25-OH vitamin D level was 25.9 ng/mL in those with recurrent disease, 27.5 ng/mL in men with clinically localized prostate cancer and 24.5 ng/mL in controls. The frequency of vitamin D deficiency (< 20 ng/mL) and insufficiency (20–31 ng/mL) was 40% and 32% in men with recurrent prostate; 28% had vitamin D levels that were normal (32–100 ng/mL). Among men with localized prostate cancer, 18% were deficient, 50% were insufficient and 32% were normal. Among controls, 31% were deficient, 40% were insufficient and 29% were normal. Metastatic disease (P = 0.005) and season of blood sampling (winter/spring; P = 0.01) were associated with vitamin D deficiency in patients with prostate cancer, while age, race, performance status and body mass index were not. Conclusions Vitamin D deficiency and insufficiency were common among men with prostate cancer and apparently normal controls in the western New York region. PMID:19426195

Vitamin D deficiency and insufficiency among patients with prostate cancer.

PubMed

Trump, Donald L; Chadha, Manpreet K; Sunga, Annette Y; Fakih, Marwan G; Ashraf, Umeer; Silliman, Carrie G; Hollis, Bruce W; Nesline, Mary K; Tian, Lili; Tan, Wei; Johnson, Candace S

2009-10-01

To assess the frequency of vitamin D deficiency among men with prostate cancer, as considerable epidemiological, in vitro, in vivo and clinical data support an association between vitamin D deficiency and prostate cancer outcome. The study included 120 ambulatory men with recurrent prostate cancer and 50 with clinically localized prostate cancer who were evaluated and serum samples assayed for 25-OH vitamin D levels. Then 100 controls (both sexes), matched for age and season of serum sample, were chosen from a prospective serum banking protocol. The relationship between age, body mass index, disease stage, Eastern Cooperative Oncology Group performance status, season and previous therapy on vitamin D status were evaluated using univariate and multivariate analyses. The mean 25-OH vitamin D level was 25.9 ng/mL in those with recurrent disease, 27.5 ng/mL in men with clinically localized prostate cancer and 24.5 ng/mL in controls. The frequency of vitamin D deficiency (<20 ng/mL) and insufficiency (20-31 ng/mL) was 40% and 32% in men with recurrent prostate; 28% had vitamin D levels that were normal (32-100 ng/mL). Among men with localized prostate cancer, 18% were deficient, 50% were insufficient and 32% were normal. Among controls, 31% were deficient, 40% were insufficient and 29% were normal. Metastatic disease (P = 0.005) and season of blood sampling (winter/spring; P = 0.01) were associated with vitamin D deficiency in patients with prostate cancer, while age, race, performance status and body mass index were not. Vitamin D deficiency and insufficiency were common among men with prostate cancer and apparently normal controls in the western New York region.

Attitudes toward Alzheimer's disease: a qualitative study of the role played by social representation on a convenient sample of French general practitioners.

PubMed

Lahjibi-Paulet, Hayat; Dauffy Alain, Agnès; Minard, Aurélien; Gaxatte, Cédric; Saint-Jean, Olivier; Somme, Dominique

2012-08-01

It is commonly thought that Alzheimer's disease (AD) is under-diagnosed and that insufficient numbers of patients are receiving pharmacological treatment. These observations are often attributed to poor management of the disease by general practitioners (GPs) related to their lack of training in identifying cognitive decline. Our hypothesis is that there may be a relation between GPs' perceptions and their attitudes toward AD. We conducted a qualitative study, through semi-directive interviews focusing on their representations, of 25 GPs, masters in training courses, in Paris. Analysis of interviews revealed five general trends. AD is seen by GPs as a "disease of autonomy", without specific medical treatment. Cognitive symptoms are less meaningful in GPs' view than the loss of autonomy. The main thing is to keep the patient at home. For GPs, the family is described as an essential partner in coping with the insufficiencies of available social programs. The use of specialists is less to confirm the diagnosis than to announce the "bad news". GPs declare scepticism as to the efficacy of AD medications, only granting them a certain "care" effect or a social role. The image of AD remains highly negative. The stigma of AD is seen as a barrier to its diagnosis. This study is somewhat preliminary because of sample size. Nevertheless, the social representations of the disease influence GPs' attitudes toward making diagnoses in France. Priority seems to focus more on assisting GPs and families at the social level, rather than diagnosis or access to treatment.

Morphometric variation in the papionin muzzle and the biochronology of the South African Plio-Pleistocene karst cave deposits.

PubMed

Gilbert, Christopher C; Grine, Frederick E

2010-03-01

Papionin monkeys are widespread, relatively common members of Plio-Pleistocene faunal assemblages across Africa. For these reasons, papionin taxa have been used as biochronological indicators by which to infer the ages of the South African karst cave deposits. A recent morphometric study of South African fossil papionin muzzle shape concluded that its variation attests to a substantial and greater time depth for these sites than is generally estimated. This inference is significant, because accurate dating of the South African cave sites is critical to our knowledge of hominin evolution and mammalian biogeographic history. We here report the results of a comparative analysis of extant papionin monkeys by which variability of the South African fossil papionins may be assessed. The muzzles of 106 specimens representing six extant papionin genera were digitized and interlandmark distances were calculated. Results demonstrate that the overall amount of morphological variation present within the fossil assemblage fits comfortably within the range exhibited by the extant sample. We also performed a statistical experiment to assess the limitations imposed by small sample sizes, such as typically encountered in the fossil record. Results suggest that 15 specimens are sufficient to accurately represent the population mean for a given phenotype, but small sample sizes are insufficient to permit the accurate estimation of the population standard deviation, variance, and range. The suggestion that the muzzle morphology of fossil papionins attests to a considerable and previously unrecognized temporal depth of the South African karst cave sites is unwarranted.

The functional spectrum of low-frequency coding variation.

PubMed

Marth, Gabor T; Yu, Fuli; Indap, Amit R; Garimella, Kiran; Gravel, Simon; Leong, Wen Fung; Tyler-Smith, Chris; Bainbridge, Matthew; Blackwell, Tom; Zheng-Bradley, Xiangqun; Chen, Yuan; Challis, Danny; Clarke, Laura; Ball, Edward V; Cibulskis, Kristian; Cooper, David N; Fulton, Bob; Hartl, Chris; Koboldt, Dan; Muzny, Donna; Smith, Richard; Sougnez, Carrie; Stewart, Chip; Ward, Alistair; Yu, Jin; Xue, Yali; Altshuler, David; Bustamante, Carlos D; Clark, Andrew G; Daly, Mark; DePristo, Mark; Flicek, Paul; Gabriel, Stacey; Mardis, Elaine; Palotie, Aarno; Gibbs, Richard

2011-09-14

Rare coding variants constitute an important class of human genetic variation, but are underrepresented in current databases that are based on small population samples. Recent studies show that variants altering amino acid sequence and protein function are enriched at low variant allele frequency, 2 to 5%, but because of insufficient sample size it is not clear if the same trend holds for rare variants below 1% allele frequency. The 1000 Genomes Exon Pilot Project has collected deep-coverage exon-capture data in roughly 1,000 human genes, for nearly 700 samples. Although medical whole-exome projects are currently afoot, this is still the deepest reported sampling of a large number of human genes with next-generation technologies. According to the goals of the 1000 Genomes Project, we created effective informatics pipelines to process and analyze the data, and discovered 12,758 exonic SNPs, 70% of them novel, and 74% below 1% allele frequency in the seven population samples we examined. Our analysis confirms that coding variants below 1% allele frequency show increased population-specificity and are enriched for functional variants. This study represents a large step toward detecting and interpreting low frequency coding variation, clearly lays out technical steps for effective analysis of DNA capture data, and articulates functional and population properties of this important class of genetic variation.

In Search of the Largest Possible Tsunami: An Example Following the 2011 Japan Tsunami

NASA Astrophysics Data System (ADS)

Geist, E. L.; Parsons, T.

2012-12-01

Many tsunami hazard assessments focus on estimating the largest possible tsunami: i.e., the worst-case scenario. This is typically performed by examining historic and prehistoric tsunami data or by estimating the largest source that can produce a tsunami. We demonstrate that worst-case assessments derived from tsunami and tsunami-source catalogs are greatly affected by sampling bias. Both tsunami and tsunami sources are well represented by a Pareto distribution. It is intuitive to assume that there is some limiting size (i.e., runup or seismic moment) for which a Pareto distribution is truncated or tapered. Likelihood methods are used to determine whether a limiting size can be determined from existing catalogs. Results from synthetic catalogs indicate that several observations near the limiting size are needed for accurate parameter estimation. Accordingly, the catalog length needed to empirically determine the limiting size is dependent on the difference between the limiting size and the observation threshold, with larger catalog lengths needed for larger limiting-threshold size differences. Most, if not all, tsunami catalogs and regional tsunami source catalogs are of insufficient length to determine the upper bound on tsunami runup. As an example, estimates of the empirical tsunami runup distribution are obtained from the Miyako tide gauge station in Japan, which recorded the 2011 Tohoku-oki tsunami as the largest tsunami among 51 other events. Parameter estimation using a tapered Pareto distribution is made both with and without the Tohoku-oki event. The catalog without the 2011 event appears to have a low limiting tsunami runup. However, this is an artifact of undersampling. Including the 2011 event, the catalog conforms more to a pure Pareto distribution with no confidence in estimating a limiting runup. Estimating the size distribution of regional tsunami sources is subject to the same sampling bias. Physical attenuation mechanisms such as wave breaking likely limit the maximum tsunami runup at a particular site. However, historic and prehistoric data alone cannot determine the upper bound on tsunami runup. Because of problems endemic to sampling Pareto distributions of tsunamis and their sources, we recommend that tsunami hazard assessment be based on a specific design probability of exceedance following a pure Pareto distribution, rather than attempting to determine the worst-case scenario.

What about N? A methodological study of sample-size reporting in focus group studies.

PubMed

Carlsen, Benedicte; Glenton, Claire

2011-03-11

Focus group studies are increasingly published in health related journals, but we know little about how researchers use this method, particularly how they determine the number of focus groups to conduct. The methodological literature commonly advises researchers to follow principles of data saturation, although practical advise on how to do this is lacking. Our objectives were firstly, to describe the current status of sample size in focus group studies reported in health journals. Secondly, to assess whether and how researchers explain the number of focus groups they carry out. We searched PubMed for studies that had used focus groups and that had been published in open access journals during 2008, and extracted data on the number of focus groups and on any explanation authors gave for this number. We also did a qualitative assessment of the papers with regard to how number of groups was explained and discussed. We identified 220 papers published in 117 journals. In these papers insufficient reporting of sample sizes was common. The number of focus groups conducted varied greatly (mean 8.4, median 5, range 1 to 96). Thirty seven (17%) studies attempted to explain the number of groups. Six studies referred to rules of thumb in the literature, three stated that they were unable to organize more groups for practical reasons, while 28 studies stated that they had reached a point of saturation. Among those stating that they had reached a point of saturation, several appeared not to have followed principles from grounded theory where data collection and analysis is an iterative process until saturation is reached. Studies with high numbers of focus groups did not offer explanations for number of groups. Too much data as a study weakness was not an issue discussed in any of the reviewed papers. Based on these findings we suggest that journals adopt more stringent requirements for focus group method reporting. The often poor and inconsistent reporting seen in these studies may also reflect the lack of clear, evidence-based guidance about deciding on sample size. More empirical research is needed to develop focus group methodology.

Shoot size significantly affects rooting response of sugar maple softwood cuttings

Treesearch

John R. Donnelly

1974-01-01

Three hundred softwood cuttings were collected from each of three mature sugar maple trees to test the effect of shoot size on adventitious root formation. One of the trees was a good rooter (61 percent rooted); one was a poor rooter (19 percent rooted); and the third was a non-rooter (1 percent rooted). There was an insufficient number of rooted cuttings from the...

Sleep Duration and Waist Circumference in Adults: A Meta-Analysis

PubMed Central

Sperry, Susan D.; Scully, Iiona D.; Gramzow, Richard H.; Jorgensen, Randall S.

2015-01-01

Background: Previous research has demonstrated a relation between insufficient sleep and overall obesity. Waist circumference (WC), a measure of central adiposity, has been demonstrated to improve prediction of health risk. However, recent research on the relation of insufficient sleep duration to WC in adults has yielded inconsistent findings. Objectives: To assess the magnitude and the consistency of the relation of insufficient sleep and WC Methods: A systematic search of Internet and research databases using Google Scholar, Medline, PubMed, and PsycINFO through July 2013 was conducted. All articles in English with adult human subjects that included measurements of WC and sleep duration were reviewed. A random effects meta-analysis and regression analyses were performed. Heterogeneity and publication bias were checked. Results are expressed as Pearson correlations (r; 95% confidence interval). Results: Of 1,376 articles, 30 met inclusion criteria and 21 studies (22 samples for a total of 56,259 participants) provided sufficient data for meta-analysis. Results showed a significant negative relation between sleep duration and WC (r = −0.10, P < 0.0001) with significant heterogeneity related to sleep comparison method. Potential moderators of the relation between sleep duration and WC were not significant. Funnel plots showed no indication of publication bias. In addition, a fail-safe N calculation indicated that 418 studies with null effects would be necessary to bring the overall mean effect size to a trivial value of r = −0.005. Conclusions: Internationally, cross-sectional studies demonstrate a significant negative relation between sleep duration and waist circumference, indicating shorter sleep durations covary with central adiposity. Future research should include prospective studies. Citation: Sperry SD, Scully ID, Gramzow RH, Jorgensen RS. Sleep duration and waist circumference in adults: a meta-analysis. SLEEP 2015;38(8):1269–1276. PMID:25581918

Reversal of Latency as Part of a Cure for HIV-1.

PubMed

Rasmussen, Thomas Aagaard; Tolstrup, Martin; Søgaard, Ole Schmeltz

2016-02-01

Here, the use of pharmacological agents to reverse HIV-1 latency will be explored as a therapeutic strategy towards a cure. However, while clinical trials of latency-reversing agents LRAs) have demonstrated their ability to increase production of latent HIV-1, such interventions have not had an effect on the size of the latent HIV-1 reservoir. Plausible explanations for this include insufficient host immune responses against virus-expressing cells, the presence of escape mutations in archived virus, or an insufficient scale of latency reversal. Importantly, these early studies of LRAs were primarily designed to investigate their ability to perturb the state of HIV-1 latency; using the absence of an impact on the size of the HIV-1 reservoir to discard their potential inclusion in curative strategies would be erroneous and premature. Copyright © 2015 Elsevier Ltd. All rights reserved.

Behavioral and Emotional Problems Associated With Convergence Insufficiency in Children: An Open Trial.

PubMed

Borsting, Eric; Mitchell, G Lynn; Arnold, L Eugene; Scheiman, Mitchell; Chase, Christopher; Kulp, Marjean; Cotter, Susan

2016-10-01

This study investigated behavioral and emotional characteristics of children with convergence insufficiency (CI), before and after treatment with office-based vergence accommodative therapy (OBVAT). Parents of 44 children ages 9 to 17 years with symptomatic CI completed the Conners 3 ADHD Index and the Child Behavior Checklist (CBCL) before and after OBVAT. Pre-treatment scores were compared with normative data and post-treatment scores were compared with baseline using the Wilcoxon sign rank test. Following OBVAT, CI children showed a significant mean improvement (p < .0001, effect size of 0.58) on the Conners 3 ADHD Index with the largest changes occurring in the 23 children who scored the highest at baseline. On the CBCL, anxious/depressed, somatic, and internalizing problems improved significantly (p < .001, effect sizes of -0.36, -1.15, and -0.67, respectively). In an open trial, attention and internalizing problems improved significantly following treatment for CI. © The Author(s) 2013.

Influence of the limited detector size on spatial variations of the reconstruction accuracy in holographic tomography

NASA Astrophysics Data System (ADS)

Kostencka, Julianna; Kozacki, Tomasz; Hennelly, Bryan; Sheridan, John T.

2017-06-01

Holographic tomography (HT) allows noninvasive, quantitative, 3D imaging of transparent microobjects, such as living biological cells and fiber optics elements. The technique is based on acquisition of multiple scattered fields for various sample perspectives using digital holographic microscopy. Then, the captured data is processed with one of the tomographic reconstruction algorithms, which enables 3D reconstruction of refractive index distribution. In our recent works we addressed the issue of spatially variant accuracy of the HT reconstructions, which results from the insufficient model of diffraction that is applied in the widely-used tomographic reconstruction algorithms basing on the Rytov approximation. In the present study, we continue investigating the spatially variant properties of the HT imaging, however, we are now focusing on the limited spatial size of holograms as a source of this problem. Using the Wigner distribution representation and the Ewald sphere approach, we show that the limited size of the holograms results in a decreased quality of tomographic imaging in off-center regions of the HT reconstructions. This is because the finite detector extent becomes a limiting aperture that prohibits acquisition of full information about diffracted fields coming from the out-of-focus structures of a sample. The incompleteness of the data results in an effective truncation of the tomographic transfer function for the out-of-center regions of the tomographic image. In this paper, the described effect is quantitatively characterized for three types of the tomographic systems: the configuration with 1) object rotation, 2) scanning of the illumination direction, 3) the hybrid HT solution combing both previous approaches.

Test Population Selection from Weibull-Based, Monte Carlo Simulations of Fatigue Life

NASA Technical Reports Server (NTRS)

Vlcek, Brian L.; Zaretsky, Erwin V.; Hendricks, Robert C.

2008-01-01

Fatigue life is probabilistic and not deterministic. Experimentally establishing the fatigue life of materials, components, and systems is both time consuming and costly. As a result, conclusions regarding fatigue life are often inferred from a statistically insufficient number of physical tests. A proposed methodology for comparing life results as a function of variability due to Weibull parameters, variability between successive trials, and variability due to size of the experimental population is presented. Using Monte Carlo simulation of randomly selected lives from a large Weibull distribution, the variation in the L10 fatigue life of aluminum alloy AL6061 rotating rod fatigue tests was determined as a function of population size. These results were compared to the L10 fatigue lives of small (10 each) populations from AL2024, AL7075 and AL6061. For aluminum alloy AL6061, a simple algebraic relationship was established for the upper and lower L10 fatigue life limits as a function of the number of specimens failed. For most engineering applications where less than 30 percent variability can be tolerated in the maximum and minimum values, at least 30 to 35 test samples are necessary. The variability of test results based on small sample sizes can be greater than actual differences, if any, that exists between materials and can result in erroneous conclusions. The fatigue life of AL2024 is statistically longer than AL6061 and AL7075. However, there is no statistical difference between the fatigue lives of AL6061 and AL7075 even though AL7075 had a fatigue life 30 percent greater than AL6061.

Test Population Selection from Weibull-Based, Monte Carlo Simulations of Fatigue Life

NASA Technical Reports Server (NTRS)

Vlcek, Brian L.; Zaretsky, Erwin V.; Hendricks, Robert C.

2012-01-01

Fatigue life is probabilistic and not deterministic. Experimentally establishing the fatigue life of materials, components, and systems is both time consuming and costly. As a result, conclusions regarding fatigue life are often inferred from a statistically insufficient number of physical tests. A proposed methodology for comparing life results as a function of variability due to Weibull parameters, variability between successive trials, and variability due to size of the experimental population is presented. Using Monte Carlo simulation of randomly selected lives from a large Weibull distribution, the variation in the L10 fatigue life of aluminum alloy AL6061 rotating rod fatigue tests was determined as a function of population size. These results were compared to the L10 fatigue lives of small (10 each) populations from AL2024, AL7075 and AL6061. For aluminum alloy AL6061, a simple algebraic relationship was established for the upper and lower L10 fatigue life limits as a function of the number of specimens failed. For most engineering applications where less than 30 percent variability can be tolerated in the maximum and minimum values, at least 30 to 35 test samples are necessary. The variability of test results based on small sample sizes can be greater than actual differences, if any, that exists between materials and can result in erroneous conclusions. The fatigue life of AL2024 is statistically longer than AL6061 and AL7075. However, there is no statistical difference between the fatigue lives of AL6061 and AL7075 even though AL7075 had a fatigue life 30 percent greater than AL6061.

Size of the lower third molar space in relation to age in Serbian population.

PubMed

Zelić, Ksenija; Nedeljković, Nenad

2013-10-01

It is considered that the shortage of space is the major cause of the third molar impaction. The aim of this study was to establish the frequency of insufficient lower third molar eruption space in Serbian population, to question the differences in this frequency in the subjects of different age, to determine the influence of the lower third molar space (retromolar space) size on third molar eruption, and to investigate a possible correlation between the size of gonial angle and the space/third molar width ratio. Digital orthopantomograms were taken from 93 patients divided into two groups: early adult (16-18 years of age) and adult (18-26) patients. Retromolar space, mesiodistal third molar crown width, gonial angle and eruption levels were measured. The space/third molar width in early adult subjects was smaller (p < 0.0001) and insufficient space was significantly more frequent (p = 0.0003) than in adult patients. Considerably more third molars erupted in case of enough space in both age groups (p < 0.0001). There was no difference between the means of gonial angle size in relations to the available space. The retromolar space/third molar width ratio is more favorable in adult subjects. Gonial angle is not in correlation with the retromolar space/third molar width ratio.

Randomized Controlled Trial to Increase Physical Activity among Insufficiently Active Women Following Their Participation in a Mass Event

ERIC Educational Resources Information Center

Lane, Aoife; Murphy, Niamh; Bauman, Adrian; Chey, Tien

2010-01-01

Objective: To assess the impact of a community based, low-contact intervention on the physical activity habits of insufficiently active women. Design: Randomized controlled trial. Participants: Inactive Irish women. Method: A population sample of women participating in a mass 10 km event were up followed at 2 and 6 months, and those who had…

Statistical correction of the Winner’s Curse explains replication variability in quantitative trait genome-wide association studies

PubMed Central

Pe’er, Itsik

2017-01-01

Genome-wide association studies (GWAS) have identified hundreds of SNPs responsible for variation in human quantitative traits. However, genome-wide-significant associations often fail to replicate across independent cohorts, in apparent inconsistency with their apparent strong effects in discovery cohorts. This limited success of replication raises pervasive questions about the utility of the GWAS field. We identify all 332 studies of quantitative traits from the NHGRI-EBI GWAS Database with attempted replication. We find that the majority of studies provide insufficient data to evaluate replication rates. The remaining papers replicate significantly worse than expected (p < 10−14), even when adjusting for regression-to-the-mean of effect size between discovery- and replication-cohorts termed the Winner’s Curse (p < 10−16). We show this is due in part to misreporting replication cohort-size as a maximum number, rather than per-locus one. In 39 studies accurately reporting per-locus cohort-size for attempted replication of 707 loci in samples with similar ancestry, replication rate matched expectation (predicted 458, observed 457, p = 0.94). In contrast, ancestry differences between replication and discovery (13 studies, 385 loci) cause the most highly-powered decile of loci to replicate worse than expected, due to difference in linkage disequilibrium. PMID:28715421

Differences in hospital casemix, and the relationship between casemix and hospital costs.

PubMed

Söderlund, N; Milne, R; Gray, A; Raftery, J

1995-03-01

The aim of the study was to examine the relationship between hospital costs and casemix, and after adjustment for casemix differences, between cost and institutional size, number of specialties, occupancy and teaching status. A retrospective analysis of all admissions to nine acute-care NHS hospitals in the Oxford region during the 1991-1992 financial year was undertaken. All episodes were assigned to a diagnosis-related group (DRG) and a cost weight assigned accordingly. Costs per finished consultant episode, before and after adjustment for casemix differences, were analysed at the hospital and specialty level. Casemix differences were significant, and accounted for approximately 77 per cent of the difference in costs between providers. Costs per casemix-adjusted episode were not significantly associated with differences in hospital size, scope, occupancy levels or teaching status, but sample size was insufficient to investigate these relationships adequately. Specialty costs were poorly correlated with specialty casemix. This was probably due to poor apportionment of specialty costs in hospital accounting returns. Casemix differences need to be taken into account when comparing providers for the purposes of contracting, as unadjusted unit costs may be misleading. Although the methods used may currently be applied to most NHS hospitals, widespread use would be greatly facilitated by the development of indigenous cost weights and better routine hospital data coding and collection.

Residential Variable-Capacity Heat Pumps Sized to Heating Loads

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

Munk, Jeffrey D.; Jackson, Roderick K.; Odukomaiya, Adewale

2014-01-01

Variable capacity heat pumps are an emerging technology offering significant energy savings potential and improved efficiency. With conventional single-speed systems, it is important to appropriately size heat pumps for the cooling load as over-sizing would result in cycling and insufficient latent capacity required for humidity control. These appropriately sized systems are often under-sized for the heating load and require inefficient supplemental electric resistance heat to meet the heating demand. Variable capacity heat pumps address these shortcomings by providing an opportunity to intentionally size systems for the dominant heating season load without adverse effects of cycling or insufficient dehumidification in themore » cooling season. This intentionally-sized system could result in significant energy savings in the heating season, as the need for inefficient supplemental electric resistance heat is drastically reduced. This is a continuation of a study evaluating the energy consumption of variable capacity heat pumps installed in two unoccupied research homes in Farragut, a suburb of Knoxville, Tennessee. In this particular study, space conditioning systems are intentionally sized for the heating season loads to provide an opportunity to understand and evaluate the impact this would have on electric resistance heat use and dehumidification. The results and conclusions drawn through this research are valid and specific for portions of the Southeastern and Midwestern United States falling in the mixed-humid climate zone. While other regions in the U.S. do not experience this type of climate, this work provides a basis for, and can help understand the implications of other climate zones on residential space conditioning energy consumption. The data presented here will provide a framework for fine tuning residential building EnergyPlus models that are being developed.« less

The association between active smoking, smokeless tobacco, second-hand smoke exposure and insufficient sleep.

PubMed

Sabanayagam, Charumathi; Shankar, Anoop

2011-01-01

Studies have shown that cigarette smoking is associated with sleep disorders in the general population. But studies examining the association between smokeless tobacco use, second-hand smoke exposure and insufficient rest/sleep are limited. We examined the association between smoking, smokeless tobacco use (n=83,072), second-hand smoke exposure (n=28,557) and insufficient rest/sleep among adults aged ≥20 years in the state-based 2008 Behavioral Risk Factor Surveillance System. Exposure to second-hand smoke was defined as >1 day of exposure to cigarette smoking either at home or in the workplace in the preceding 7 days. Insufficient rest/sleep was defined as not getting enough rest/sleep everyday in the preceding 30 days. Compared to never smokeless tobacco users, the odds ratio (OR; 95% confidence interval [CI]) of insufficient rest/sleep was 1.16 (1.00-1.36) and 1.74 (1.37-2.22) among former and current users. Compared to non-smokers/non-smokeless tobacco users, the OR (95% CI) of insufficient rest/sleep for those who were both current smokers and current smokeless tobacco users was 2.21 (1.66-2.94). Regarding second-hand smoke exposure among non-smokers, those with second-hand smoke exposure had higher odds for insufficient rest/sleep than those without. In contrast, the odds of insufficient rest/sleep were similar among current smokers with or without second-hand smoke exposure. In a multiethnic sample of US adults, compared to non-smokers/non-smokeless tobacco users, those who were both current smokers and current smokeless tobacco users had twice the odds of insufficient sleep. Second-hand smoke exposure was associated with insufficient rest/sleep among non-smokers. Copyright © 2010 Elsevier B.V. All rights reserved.

Estimating Dermal Transfer of Copper Particles from the ...

EPA Pesticide Factsheets

Lumber pressure-treated with micronized copper was examined for the release of copper and copper micro/nanoparticles using a surface wipe method to simulate dermal transfer. In 2003, the wood industry began replacing CCA treated lumber products for residential use with copper based formulations. Micronized copper (nano to micron sized particles) has become the preferred treatment formulation. There is a lack of information on the release of copper, the fate of the particles during dermal contact, and the copper exposure level to children from hand-to-mouth transfer. For the current study, three treated lumber products, two micronized copper and one ionic copper, were purchased from commercial retailers. The boards were left to weather outdoors for approximately 1 year. Over the year time period, hand wipe samples were collected periodically to determine copper transfer from the wood surfaces. The two micronized formulations and the ionic formulation released similar levels of total copper. The amount of copper released was high initially, but decreased to a constant level (~1.5 mg m-2) after the first month of outdoor exposure. Copper particles were identified on the sampling cloths during the first two months of the experiment, after which the levels of copper were insufficient to collect interpretable data. After 1 month, the particles exhibited minimal changes in shape and size. At the end of 2-months, significant deterioration of the particles was

Therapy of the burnout syndrome.

PubMed

Korczak, Dieter; Wastian, Monika; Schneider, Michael

2012-01-01

The prevalence, diagnostics and therapy of the burnout syndrome are increasingly discussed in the public. The unclear definition and diagnostics of the burnout syndrome are scientifically criticized. There are several therapies with unclear evidence for the treatment of burnout in existence. The health technology assessment (HTA) report deals with the question of usage and efficacy of different burnout therapies. For the years 2006 to 2011, a systematic literature research was done in 31 electronic databases (e.g. EMBASE, MEDLINE, PsycINFO). Important inclusion criteria are burnout, therapeutic intervention and treatment outcome. 17 studies meet the inclusion criteria and are regarded for the HTA report. The studies are very heterogeneous (sample size, type of intervention, measuring method, level of evidence). Due to their study design (e.g. four reviews, eight randomized controlled trials) the studies have a comparable high evidence: three times 1A, five times 1B, one time 2A, two times 2B and six times 4. 13 of the 17 studies are dealing with the efficacy of psychotherapy and psychosocial interventions for the reduction of burnout (partly in combination with other techniques). Cognitive behaviour therapy leads to the improvement of emotional exhaustion in the majority of the studies. The evidence is inconsistent for the efficacy of stress management and music therapy. Two studies regarding the efficacy of Qigong therapy do not deliver a distinct result. One study proves the efficacy of roots of Rhodiola rosea (evidence level 1B). Physical therapy is only in one study separately examined and does not show a better result than standard therapy. Despite the number of studies with high evidence the results for the efficacy of burnout therapies are preliminary and do have only limited reach. The authors of the studies complain about the low number of skilled studies for the therapy of burnout. Furthermore, they point to the insufficient evaluation of the therapy studies and the need for further research. Some authors report the effects of considerable natural recovering. Numerous limitations affect the quality of the results. Intervention contents and duration, study design and study size are very diverse and do not permit direct comparison. Most of the samples are small by size with low statistical power, long-term follow-ups are missing. Comorbidities and parallel utilized therapies are insufficient documented or controlled. Most of the studies use the Maslach Burnout Inventory (MBI) as diagnostic or outcome-tool, but with different cut-off-points. It should be noticed that the validity of the MBI as diagnostic tool is not proved. Ethical, juridical and social determining factors are not covered or discussed in the studies. The efficacy of therapies for the treatment of the burnout syndrome is insufficient investigated. Only for cognitive behavioural therapy (CBT) exists an adequate number of studies which prove its efficacy. Big long-term experimental studies are missing which compare the efficacy of the single therapies and evaluate their evidence. The natural recovering without any therapy needs further research. Additionally, it has to be examined to what extent therapies and their possible effects are thwarted by the conditions of the working place and the working conditions.

A comparison of direct medical costs across racial and ethnic groups among children with cancer.

PubMed

Wang, Junling; Dong, Zhiyong; Hong, Song Hee; Suda, Katie J

2008-03-01

Previous studies reported that some minority childhood cancer patients are likely to develop worse outcomes than white children. This study examines whether there are racial and ethnic disparities in health expenditures among children with cancer. A retrospective study was conducted among children (younger than 20) with cancer diagnoses in the Medical Expenditure Panel Survey (MEPS; 1996 to 2004). Total health expenditures and the following subcategories were examined across racial and ethnic groups: (1) office-based visits; (2) outpatient visits; (3) inpatient and emergency room visits; (4) home health care; (5) prescription drugs; and (6) dental, vision, and other health care expenditures. Consumer price indexes were used to convert all expenditures to 2004 dollars. A classical linear model was analyzed using the natural logarithm of health expenditures as the dependent variable, with the purpose of determining whether there were racial and ethnic differences in health expenditures after adjusting for confounding factors. Study sample included 394 non-Hispanic whites (weighted to 4 958 685), 53 non-Hispanic blacks (weighted to 352 534), and 94 Hispanic whites (weighted to 424 319). Hispanic blacks and other minority populations were excluded from the analysis due to insufficient sample size. The annual total health expenditure for treating each child with cancer was $3467.40, $2156.15, and $5545.34, respectively, among non-Hispanic whites, non-Hispanic blacks, and Hispanic whites. The differences in the various subcategories of health expenditures across racial and ethnic groups were generally not significant according to both descriptive and analytical analyses with very few exceptions. This study did not identify significant racial and ethnic disparities in health care costs. However, one important study limitation is the small sample size of the minority populations in the study sample.

Vitamin D Deficiency in Children and Adolescents in Bağcılar, İstanbul

PubMed Central

Erol, Meltem; Yiğit, Özgül; Küçük, Suat Hayri; Bostan Gayret, Özlem

2015-01-01

Objective: This study aimed to evaluate the frequency of seasonal 25-hydroxyvitamin D [25(OH)D] deficiency and insufficiency in children and adolescents living in Bağcılar, district of İstanbul city. Methods: Serum vitamin D levels of 280 children aged 3-17 years old were measured at the end of winter and at the end of summer. Of the total group, vitamin D levels were re-measured in 198 subjects. Vitamin D deficiency was defined as a serum 25(OH)D level less than 15 ng/mL and insufficiency-as levels between 15 and 20 ng/mL. Patients whose vitamin D levels were less than 15 ng/mL at the end of winter were treated with 2000 units/day of vitamin D for 3 months. Results: In the “end of winter” samples, 25(OH)D deficiency was present in 80.36% of the subjects and insufficiency in 11.79%. In the “end of summer” samples, vitamin D deficiency was detected in 3.44% and insufficiency in 27.75%. Vitamin D levels in the “end of winter” samples were not significantly different between boys and girls, while “end of summer” levels were significantly lower in girls (p=0.015). Sunlight exposure was significantly higher in boys (p=0.011). The group with sufficient dairy product consumption had significantly higher vitamin D levels in both “end of summer” and “end of winter” samples. Limb pain was frequently reported in children with low vitamin D levels in the “end of winter” samples (p=0.001). Negative correlations were observed between vitamin D levels and season and also between vitamin D levels and age. Conclusion: It is essential to provide supplemental vitamin D to children and adolescents to overcome the deficiency seen especially at the end of winter. PMID:26316436

Cation disorder in MgX2O4 (X = Al, Ga, In) spinels from first principles

NASA Astrophysics Data System (ADS)

Jiang, Chao; Sickafus, Kurt E.; Stanek, Christopher R.; Rudin, Sven P.; Uberuaga, Blas P.

2012-07-01

We have performed first-principles density functional theory calculations to investigate the possible physical origins of the discrepancies between the existing theoretical and experimental studies on cation distribution in MgX2O4 (X = Al, Ga, In) spinel oxides. We show that for MgGa2O4 and MgIn2O4, it is crucial to consider the effects of lattice vibrations to achieve agreement between theory and experiment. For MgAl2O4, we find that neglecting short-range order effects in thermodynamic modeling can lead to significant underestimation of the degree of inversion. Furthermore, we demonstrate that the common practice of representing disordered structures by randomly exchanging atoms within a small periodic supercell can incur large computational error due to either insufficient statistical sampling or finite supercell size effects.

Clustering of quasars in SDSS-IV eBOSS: study of potential systematics and bias determination

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

Laurent, Pierre; Goff, Jean-Marc Le; Burtin, Etienne

2017-07-01

We study the first year of the eBOSS quasar sample in the redshift range 0.9< z <2.2 which includes 68,772 homogeneously selected quasars. We show that the main source of systematics in the evaluation of the correlation function arises from inhomogeneities in the quasar target selection, particularly related to the extinction and depth of the imaging data used for targeting. We propose a weighting scheme that mitigates these systematics. We measure the quasar correlation function and provide the most accurate measurement to date of the quasar bias in this redshift range, b {sub Q} = 2.45 ± 0.05 at z-barmore » =1.55, together with its evolution with redshift. We use this information to determine the minimum mass of the halo hosting the quasars and the characteristic halo mass, which we find to be both independent of redshift within statistical error. Using a recently-measured quasar-luminosity-function we also determine the quasar duty cycle. The size of this first year sample is insufficient to detect any luminosity dependence to quasar clustering and this issue should be further studied with the final ∼500,000 eBOSS quasar sample.« less

Clustering of quasars in SDSS-IV eBOSS: study of potential systematics and bias determination

NASA Astrophysics Data System (ADS)

Laurent, Pierre; Eftekharzadeh, Sarah; Le Goff, Jean-Marc; Myers, Adam; Burtin, Etienne; White, Martin; Ross, Ashley J.; Tinker, Jeremy; Tojeiro, Rita; Bautista, Julian; Brinkmann, Jonathan; Comparat, Johan; Dawson, Kyle; du Mas des Bourboux, Hélion; Kneib, Jean-Paul; McGreer, Ian D.; Palanque-Delabrouille, Nathalie; Percival, Will J.; Prada, Francisco; Rossi, Graziano; Schneider, Donald P.; Weinberg, David; Yèche, Christophe; Zarrouk, Pauline; Zhao, Gong-Bo

2017-07-01

We study the first year of the eBOSS quasar sample in the redshift range 0.9

[The vitamin D nutritional status in Chinese urban women of child-bearing age from 2010 to 2012].

PubMed

Lu, J X; Liu, X B; Chen, J; Hu, Y C; Yun, C F; Li, W D; Wang, R; Yang, Y H; Mao, D Q; Piao, J H; Yang, X G; Yang, L C

2017-02-06

Objective: To evaluate the vitamin D nutritional status in Chinese women of child-bearing age by analyzing serum 25-hydroxyvitamin D level in 2010-2012. Methods: Data were obtained from the China Nutrition and Health Survey in 2010-2012. Using cluster sampling and proportional stratified random sampling, 1 514 women of child-bearing age (18-44 years old) from 34 metropolis and 41 small and medium-sized cities were included in this study. Demographic information was collected by questionnaire and serum 25-hydroxyvitamin D concentration was determined by radioimmunoassay, in accordance with the 2010 Institute of Medicine of the National Academies standards. We compared differences in vitamin D levels, specifically serious deficiency, lack of deficiency, insufficiency, and excess. Results: The overall serum 25-hydroxyvitamin D level of Chinese urban women of child-bearing age ( P (50) ( P (25)- P (75))) was 20.1 (15.1-26.3) ng/ml; minorities had a significantly higher serum 25-hydroxyvitamin D level of 22.0 (15.9-27.5) ng/ml compared with women of Han nationality (19.8 (14.9-26.2) ng/ml) (χ(2)=7.02, P= 0.008). The proportions of women with serious deficiency, lack of deficiency, insufficiency, and excess vitamin D were 11.6% ( n= 175), 37.9% ( n= 574), 35.1% ( n= 531), and 0.3% ( n= 5), respectively. Only 15.1% ( n= 229) of women of child-bearing age had normal vitamin D nutritional status. No significant differences in vitamin D nutritional status were observed according to age, body mass index, city, nationality, educational level, marital status, or household income per capita ( P> 0.05). Conclusion: Most Chinese urban women of child-bearing age have poor vitamin D levels and require vitamin D supplementation.

Increased risk for school violence-related behaviors among adolescents with insufficient sleep.

PubMed

Hildenbrand, Aimee K; Daly, Brian P; Nicholls, Elizabeth; Brooks-Holliday, Stephanie; Kloss, Jacqueline D

2013-06-01

School violence is associated with significant acute and long-term negative health outcomes. Previous investigations have largely neglected the role of pertinent health behaviors in school violence, including sleep. Insufficient sleep is associated with adverse physical, behavioral, and psychosocial consequences among adolescents, many of which are concurrently implicated in youth violence. This study examined the relationship between insufficient sleep and school violence behaviors in a nationally representative sample of high school students. We used data from the 2009 National Youth Risk Behavior Survey (YRBS). Logistic regression analyses evaluated the association between insufficient sleep and school violence behaviors, controlling for demographic factors. In addition to examining main effects, interaction terms were entered into the models to examine whether potential associations varied by sex or race/ethnicity. Students with insufficient sleep had higher odds of engaging in the majority of school violence-related behaviors examined compared to students with sufficient sleep. Males with insufficient sleep were at increased risk of weapon carrying at school, a finding not observed for females with insufficient sleep. White students with insufficient sleep had higher odds of missing school because of safety concerns, a pattern that did not emerge among Black and Hispanic/Latino students. Results highlight the potential value of incorporating sleep education interventions into school-based violence prevention programs and underline the need for further examination of the relationship between sleep and school violence among adolescents. © 2013, American School Health Association.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on Surgical Resection for the Treatment of Patients With Vestibular Schwannomas.

PubMed

Hadjipanayis, Constantinos G; Carlson, Matthew L; Link, Michael J; Rayan, Tarek A; Parish, John; Atkins, Tyler; Asher, Anthony L; Dunn, Ian F; Corrales, C Eduardo; Van Gompel, Jamie J; Sughrue, Michael; Olson, Jeffrey J

2018-02-01

What surgical approaches for vestibular schwannomas (VS) are best for complete resection and facial nerve (FN) preservation when serviceable hearing is present? There is insufficient evidence to support the superiority of either the middle fossa (MF) or the retrosigmoid (RS) approach for complete VS resection and FN preservation when serviceable hearing is present. Which surgical approach (RS or translabyrinthine [TL]) for VS is best for complete resection and FN preservation when serviceable hearing is not present? There is insufficient evidence to support the superiority of either the RS or the TL approach for complete VS resection and FN preservation when serviceable hearing is not present. Does VS size matter for facial and vestibulocochlear nerve preservation with surgical resection? Level 3: Patients with larger VS tumor size should be counseled about the greater than average risk of loss of serviceable hearing. Should small intracanalicular tumors (<1.5 cm) be surgically resected? There are insufficient data to support a firm recommendation that surgery be the primary treatment for this subclass of VSs. Is hearing preservation routinely possible with VS surgical resection when serviceable hearing is present? Level 3: Hearing preservation surgery via the MF or the RS approach may be attempted in patients with small tumor size (<1.5 cm) and good preoperative hearing. When should surgical resection be the initial treatment in patients with neurofibromatosis type 2 (NF2)? There is insufficient evidence that surgical resection should be the initial treatment in patients with NF2. Does a multidisciplinary team, consisting of neurosurgery and neurotology, provides the best outcomes of complete resection and facial/vestibulocochlear nerve preservation for patients undergoing resection of VSs? There is insufficient evidence to support stating that a multidisciplinary team, usually consisting of a neurosurgeon and a neurotologist, provides superior outcomes compared to either subspecialist working alone. Does a subtotal surgical resection of a VS followed by stereotactic radiosurgery (SRS) to the residual tumor provide comparable hearing and FN preservation to patients who undergo a complete surgical resection? There is insufficient evidence to support subtotal resection (STR) followed by SRS provides comparable hearing and FN preservation to patients who undergo a complete surgical resection. Does surgical resection of VS treat preoperative balance problems more effectively than SRS? There is insufficient evidence to support either surgical resection or SRS for treatment of preoperative balance problems. Does surgical resection of VS treat preoperative trigeminal neuralgia more effectively than SRS? Level 3: Surgical resection of VSs may be used to better relieve symptoms of trigeminal neuralgia than SRS. Is surgical resection of VSs more difficult (associated with higher facial neuropathies and STR rates) after initial treatment with SRS? Level 3: If microsurgical resection is necessary after SRS, it is recommended that patients be counseled that there is an increased likelihood of a STR and decreased FN function.  The full guideline can be found at: https://www.cns.org/guidelines/guidelines-management-patients-vestibular-schwannoma/chapter_8. Copyright © 2017 by the Congress of Neurological Surgeons

Platinum Nanocatalyst Amplification: Redefining the Gold Standard for Lateral Flow Immunoassays with Ultrabroad Dynamic Range

PubMed Central

2017-01-01

Paper-based lateral flow immunoassays (LFIAs) are one of the most widely used point-of-care (PoC) devices; however, their application in early disease diagnostics is often limited due to insufficient sensitivity for the requisite sample sizes and the short time frames of PoC testing. To address this, we developed a serum-stable, nanoparticle catalyst-labeled LFIA with a sensitivity surpassing that of both current commercial and published sensitivities for paper-based detection of p24, one of the earliest and most conserved biomarkers of HIV. We report the synthesis and characterization of porous platinum core–shell nanocatalysts (PtNCs), which show high catalytic activity when exposed to complex human blood serum samples. We explored the application of antibody-functionalized PtNCs with strategically and orthogonally modified nanobodies with high affinity and specificity toward p24 and established the key larger nanoparticle size regimes needed for efficient amplification and performance in LFIA. Harnessing the catalytic amplification of PtNCs enabled naked-eye detection of p24 spiked into sera in the low femtomolar range (ca. 0.8 pg·mL–1) and the detection of acute-phase HIV in clinical human plasma samples in under 20 min. This provides a versatile absorbance-based and rapid LFIA with sensitivity capable of significantly reducing the HIV acute phase detection window. This diagnostic may be readily adapted for detection of other biomolecules as an ultrasensitive screening tool for infectious and noncommunicable diseases and can be capitalized upon in PoC settings for early disease detection. PMID:29215864

Rational and Safe Design of Concrete Transportation Structures for Size Effect and Multi-Decade Sustainability

DOT National Transportation Integrated Search

2012-10-01

The overall goal of this project was to improve the safety and sustainability in the design of large : prestressed concrete bridges and other transportation structures. The safety of large concrete : structures, including bridges, has been insufficie...

Hyperbaric versus plain bupivacaine for spinal anesthesia for cesarean delivery.

PubMed

Heng Sia, Alex Tiong; Tan, Kok Hian; Sng, Ban Leong; Lim, Yvonne; Chan, Edwin S Y; Siddiqui, Fahad Javaid

2015-01-01

Bupivacaine is an amide local anesthetic used in hyperbaric and plain forms administered as spinal anesthesia for cesarean delivery. In this systematic review, we summarized the effectiveness and safety of hyperbaric versus plain bupivacaine in providing anesthesia for cesarean delivery. We considered the adequacy of anesthesia for completion of cesarean delivery and the need for interventions to treat complications. We searched the CENTRAL, MEDLINE, and EMBASE databases. We imposed no language restriction. We included all randomized controlled trials involving patients undergoing spinal anesthesia for elective cesarean delivery that compared the use of hyperbaric bupivacaine with plain bupivacaine. We included 6 studies with a total of 394 patients in this review. These studies have small sample size, few observed events, differences in methodology, and insufficient information pertaining to assessment of risk of bias. This prevented us from calculating pooled estimates. Results show that there is no compelling evidence in favor of the use of intrathecal plain or hyperbaric bupivacaine for spinal anesthesia for cesarean delivery. There is a lack of clear evidence regarding the superiority of hyperbaric compared with plain bupivacaine for spinal anesthesia for cesarean delivery. The need for conversion to general anesthesia because of failed spinal anesthesia is an important clinical outcome, but current data are insufficient to compare spinal anesthesia induced with hyperbaric compared with plain bupivacaine for this outcome. Further research is required.

Enhanced sampling techniques in molecular dynamics simulations of biological systems.

PubMed

Bernardi, Rafael C; Melo, Marcelo C R; Schulten, Klaus

2015-05-01

Molecular dynamics has emerged as an important research methodology covering systems to the level of millions of atoms. However, insufficient sampling often limits its application. The limitation is due to rough energy landscapes, with many local minima separated by high-energy barriers, which govern the biomolecular motion. In the past few decades methods have been developed that address the sampling problem, such as replica-exchange molecular dynamics, metadynamics and simulated annealing. Here we present an overview over theses sampling methods in an attempt to shed light on which should be selected depending on the type of system property studied. Enhanced sampling methods have been employed for a broad range of biological systems and the choice of a suitable method is connected to biological and physical characteristics of the system, in particular system size. While metadynamics and replica-exchange molecular dynamics are the most adopted sampling methods to study biomolecular dynamics, simulated annealing is well suited to characterize very flexible systems. The use of annealing methods for a long time was restricted to simulation of small proteins; however, a variant of the method, generalized simulated annealing, can be employed at a relatively low computational cost to large macromolecular complexes. Molecular dynamics trajectories frequently do not reach all relevant conformational substates, for example those connected with biological function, a problem that can be addressed by employing enhanced sampling algorithms. This article is part of a Special Issue entitled Recent developments of molecular dynamics. Copyright © 2014 Elsevier B.V. All rights reserved.

Transient severe tricuspid regurgitation after transplantation of an extremely oversized donor heart in a child-Does size matter? A case report.

PubMed

Birnbaum, J; Ulrich, S M; Schramm, R; Hagl, C; Lehner, A; Fischer, M; Haas, N A; Heineking, B

2017-02-01

In pediatric heart transplantation, the size of the donor organ is an important criterion for organ allocation. Oversized donor hearts are often accepted with good results, but some complications in relation to a high donor-recipient ratio have been described. Our patient was transplanted for progressive heart failure in dilated cardiomyopathy. The donor-to-recipient weight ratio was 3 (donor weight 65 kg, recipient weight 22 kg). The intra-operative echocardiography before chest closure showed excellent cardiac function, no tricuspid valve regurgitation, and a normal central venous pressure. After chest closure, central venous pressure increased substantially and echocardiography revealed a severe tricuspid insufficiency. As other reasons for right ventricular dysfunction, that is, myocardial ischemia, pulmonary hypertension, and rejection, were excluded, we assumed that the insufficiency was caused by an alteration of the right ventricular geometry. After 1 week, the valve insufficiency regressed to a minimal degree. In pediatric heart transplant patients with a high donor-to-recipient weight ratio, the outlined complication may occur. If other reasons for right ventricular heart failure can be ruled out, this entity is most likely caused by an acute and transient alteration of the right ventricular geometry that may disappear over time. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Evaluation of three inverse problem models to quantify skin microcirculation using diffusion-weighted MRI

NASA Astrophysics Data System (ADS)

Cordier, G.; Choi, J.; Raguin, L. G.

2008-11-01

Skin microcirculation plays an important role in diseases such as chronic venous insufficiency and diabetes. Magnetic resonance imaging (MRI) can provide quantitative information with a better penetration depth than other noninvasive methods, such as laser Doppler flowmetry or optical coherence tomography. Moreover, successful MRI skin studies have recently been reported. In this article, we investigate three potential inverse models to quantify skin microcirculation using diffusion-weighted MRI (DWI), also known as q-space MRI. The model parameters are estimated based on nonlinear least-squares (NLS). For each of the three models, an optimal DWI sampling scheme is proposed based on D-optimality in order to minimize the size of the confidence region of the NLS estimates and thus the effect of the experimental noise inherent to DWI. The resulting covariance matrices of the NLS estimates are predicted by asymptotic normality and compared to the ones computed by Monte-Carlo simulations. Our numerical results demonstrate the effectiveness of the proposed models and corresponding DWI sampling schemes as compared to conventional approaches.

Impact-induced tensional failure in rock

NASA Technical Reports Server (NTRS)

Ahrens, Thomas J.; Rubin, Allan M.

1993-01-01

Planar impact experiments were employed to induce dynamic tensile failure in Bedford limestone. Rock disks were impacted with aluminum and polymethyl methacralate flyer plates at velocities of 10 to 25 m/s. This resulted in tensile stresses in the range of 11 to 160 MPa. Tensile stress durations of 0.5 and 1.3 microsec induced microcrack growth which in many experiments were insufficient to cause complete spalling of the samples. Velocity reduction, and by inference microcrack production, occurred in samples subjected to stresses above 35 MPa in the 1.3-microsec PMMA experiments and 60 MPa in the 0.5-microsec aluminum experiments. Apparent fracture toughnesses of 2.4 and 2.5 MPa m exp 1/2 are computed for the 1.3- and 0.5-microsec experiments. Three-dimensional impact experiments were conducted on 20 cm-sized blocks of Bedford limestone and San Marcos gabbro. Compressional wave velocity deficits up to 50-60 percent were observed in the vicinity of the crater. The damage decreases as about r exp -1.5 from the crater, indicating a dependence on the magnitude and duration of the tensile pulse.

The problem of pseudoreplication in neuroscientific studies: is it affecting your analysis?

PubMed Central

2010-01-01

Background Pseudoreplication occurs when observations are not statistically independent, but treated as if they are. This can occur when there are multiple observations on the same subjects, when samples are nested or hierarchically organised, or when measurements are correlated in time or space. Analysis of such data without taking these dependencies into account can lead to meaningless results, and examples can easily be found in the neuroscience literature. Results A single issue of Nature Neuroscience provided a number of examples and is used as a case study to highlight how pseudoreplication arises in neuroscientific studies, why the analyses in these papers are incorrect, and appropriate analytical methods are provided. 12% of papers had pseudoreplication and a further 36% were suspected of having pseudoreplication, but it was not possible to determine for certain because insufficient information was provided. Conclusions Pseudoreplication can undermine the conclusions of a statistical analysis, and it would be easier to detect if the sample size, degrees of freedom, the test statistic, and precise p-values are reported. This information should be a requirement for all publications. PMID:20074371

The psychosocial effects of cleft lip and palate in non-Anglo populations: a cross-cultural meta-analysis.

PubMed

Hutchinson, Kathleen; Wellman, Maria A; Noe, Douglas A; Kahn, Alice

2011-09-01

A meta-analytic study was conducted to examine the cross-cultural psychosocial impact of cleft lip and/or palate in non-Anglo populations. A total of 333 citations were initially identified for review using electronic and hand-search strategies. Of the six studies that met inclusion criteria, two were later excluded due to insufficient data. The four remaining studies represented a combined sample size of 2276 adolescents and adults with cleft lip and/or palate from China, Hong Kong, Taiwan, and Norway. Effect size using Cohen's d and confidence intervals were estimated using data from four studies of empirical, controlled study designs. The magnitude of effect sizes indicated that men (d = -0.75) with cleft lip and/or palate in non-Anglo cultures are more prone to psychosocial issues than women (d = -0.33). Adults (d = -0.50) are more impacted than adolescents (d = -0.04). Overall, regardless of age, gender, or culture, individuals with cleft lip and/or palate have lower psychosocial development than individuals without cleft lip and/or palate (d = -0.42). The effects for the cross-cultural comparisons were moderated by the age group and gender of the participants; however, most studies resulted in negative effect sizes. Health care teams for cleft lip and/or palate should recognize the importance of psychological intervention and family support in the treatment of all patients with cleft lip and/or palate throughout the life span.

Low-income Children's participation in the National School Lunch Program and household food insufficiency.

PubMed

Huang, Jin; Barnidge, Ellen

2016-02-01

Assessing the impact of the National School Lunch Program (NSLP) on household food insufficiency is critical to improve the implementation of public food assistance and to improve the nutrition intake of low-income children and their families. To examine the association of receiving free/reduced-price lunch from the NSLP with household food insufficiency among low-income children and their families in the United States, the study used data from four longitudinal panels of the Survey of Income and Program Participation (SIPP; 1996, 2001, 2004, and 2008), which collected information on household food insufficiency covering both summer and non-summer months. The sample included 15, 241 households with at least one child (aged 5-18) receiving free/reduced-price lunch from the NSLP. A dichotomous measure describes whether households have sufficient food to eat in the observed months. Fixed-effects regression analysis suggests that the food insufficiency rate is .7 (95%CI: .1, 1.2) percentage points higher in summer months among NSLP recipients. Since low-income families cannot participate in the NSLP in summer when the school is not in session, the result indicates the NSLP participation is associated with a reduction of food insufficiency risk by nearly 14%. The NSLP plays a significant role to protect low-income children and their families from food insufficiency. It is important to increase access to school meal programs among children at risk of food insufficiency in order to ensure adequate nutrition and to mitigate the health problems associated with malnourishment among children. Copyright © 2015 Elsevier Ltd. All rights reserved.

40 CFR 761.347 - First level sampling-waste from existing piles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... strength to reach from the top of the marker at the top of the pile to the farthest peripheral edge at the... device marked with zero straight down into the pile until it reaches the bottom of the pile or ground... extraction and analysis. If there is insufficient sample for a 19-liter sample from the composite sample...

Level of Inhibition in Trained Secondary School Teachers: Evidence from Pakistan

ERIC Educational Resources Information Center

Rafiq, Fauzia; Sharjeel, Yousuf

2014-01-01

The study found that the inhibition amongst trained secondary school teachers in using learned teaching methodologies is caused due to the lack of content knowledge, insufficient support from the administration, scarce continuous professional development opportunities, unsupportive environment, large class size, inefficiency to integrate…

Neurofeedback in autism spectrum disorders.

PubMed

Holtmann, Martin; Steiner, Sabina; Hohmann, Sarah; Poustka, Luise; Banaschewski, Tobias; Bölte, Sven

2011-11-01

To review current studies on the effectiveness of neurofeedback as a method of treatment of the core symptoms of autism spectrum disorders (ASD). Studies were selected based on searches in PubMed, Ovid MEDLINE, EMBASE, ERIC, and CINAHL using combinations of the following keywords: 'Neurofeedback' OR 'EEG Biofeedback' OR 'Neurotherapy' OR 'Mu-Rhythm' OR 'SMR' AND 'Autism' OR 'Autism Spectrum Disorder' OR 'Pervasive Developmental Disorder'. The existing evidence does not support the use of neurofeedback in the treatment of ASD. Studies with outcomes in favour of neurofeedback might be showing an improvement in comorbid attention-deficit-hyperactivity disorder symptoms rather than a true improvement in core ASD symptoms. Limitations of this review are those inherent in the studies available, including small sample size, short duration, variable diagnostic criteria, and insufficient control interventions, all causing a lack of generalizability. © The Authors. Developmental Medicine & Child Neurology © 2011 Mac Keith Press.

The effect of polymorphism on powder compaction and dissolution properties of chemically equivalent oxytetracycline hydrochloride powders.

PubMed

Liebenberg, W; de Villiers, M M; Wurster, D E; Swanepoel, E; Dekker, T G; Lötter, A P

1999-09-01

In South Africa, oxytetracycline is identified as an essential drug; many generic products are on the market, and many more are being developed. In this study, six oxytetracycline hydrochloride powders were obtained randomly from manufacturers, and suppliers were compared. It was found that compliance to a pharmacopoeial monograph was insufficient to ensure the optimum dissolution performance of a simple tablet formulation. Comparative physicochemical raw material analysis showed no major differences with regard to differential scanning calorimetry (DSC), infrared (IR) spectroscopy, powder dissolution, and particle size. However, the samples could be divided into two distinct types with respect to X-ray powder diffraction (XRD) and thus polymorphism. The two polymorphic forms had different dissolution properties in water or 0.1 N hydrochloride acid. This difference became substantial when the dissolution from tablets was compared. The powders containing form A were less soluble than that containing form B.

Implications of clinical trial design on sample size requirements.

PubMed

Leon, Andrew C

2008-07-01

The primary goal in designing a randomized controlled clinical trial (RCT) is to minimize bias in the estimate of treatment effect. Randomized group assignment, double-blinded assessments, and control or comparison groups reduce the risk of bias. The design must also provide sufficient statistical power to detect a clinically meaningful treatment effect and maintain a nominal level of type I error. An attempt to integrate neurocognitive science into an RCT poses additional challenges. Two particularly relevant aspects of such a design often receive insufficient attention in an RCT. Multiple outcomes inflate type I error, and an unreliable assessment process introduces bias and reduces statistical power. Here we describe how both unreliability and multiple outcomes can increase the study costs and duration and reduce the feasibility of the study. The objective of this article is to consider strategies that overcome the problems of unreliability and multiplicity.

Treatment of personality disorder.

PubMed

Bateman, Anthony W; Gunderson, John; Mulder, Roger

2015-02-21

The evidence base for the effective treatment of personality disorders is insufficient. Most of the existing evidence on personality disorder is for the treatment of borderline personality disorder, but even this is limited by the small sample sizes and short follow-up in clinical trials, the wide range of core outcome measures used by studies, and poor control of coexisting psychopathology. Psychological or psychosocial intervention is recommended as the primary treatment for borderline personality disorder and pharmacotherapy is only advised as an adjunctive treatment. The amount of research about the underlying, abnormal, psychological or biological processes leading to the manifestation of a disordered personality is increasing, which could lead to more effective interventions. The synergistic or antagonistic interaction of psychotherapies and drugs for treating personality disorder should be studied in conjunction with their mechanisms of change throughout the development of each. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biodegradable stents for the treatment of refractory or recurrent benign esophageal stenosis.

PubMed

Imaz-Iglesia, Iñaki; García-Pérez, Sonia; Nachtnebel, Anna; Martín-Águeda, Belén; Sánchez-Piedra, Carlos; Karadayi, Bilgehan; Demirbaş, Ali Rıza

2016-06-01

Esophageal stents are used for the treatment of refractory and recurrent dyphagias. In 2007, esophageal biodegradable stents (EBS) were authorised as an alternative to existing metal and plastic stents in Europe. The advantages claimed for EBS are fewer complications concerning tissue ingrowth, stent migration and stent removal. We performed a systematic review to evaluate the efficacy and safety of EBS compared to fully-covered self-expanding metal stents, self-expanding plastic stents, and esophageal dilation for the treatment of refractory or recurrent benign esophageal stenosis. Three comparative studies (one randomized controlled trial and two cohort studies) were assessed. The studies used different inclusion criteria, had a very small (sample) size and the quality of the evidence was very low. Expert commentary: The current evidence is insufficient to determine the relative efficacy or safety of esophageal biodegradable stents. The results of this systematic review should be updated once new evidence is available.

The neurocognitive consequences of sleep restriction: A meta-analytic review.

PubMed

Lowe, Cassandra J; Safati, Adrian; Hall, Peter A

2017-09-01

The current meta-analytic review evaluated the effects of experimentally manipulated sleep restriction on neurocognitive functioning. Random-effects models were employed to estimate the overall effect size and the differential effect size across cognitive domains. Age, time of day, age-adjusted sleep deficit, cumulative days of restricted sleep, sleep latency, subjective sleepiness, and biological sex were examined as potential moderators of the effect. Based on a sample of 61 studies, from 71 different populations, findings revealed a significant negative effect of sleep restriction on cognitive processing across cognitive domains (g=-0.383, p<0.001). This effect held for executive functioning (g=-0.324, p<0.001), sustained attention (g=-0.409, p<0.001), and long-term memory (g=-0.192, p=0.002). There was insufficient evidence to detect an effect within the domains of attention, multitask, impulsive decision-making or intelligence. Age group, time of day, cumulative days of restricted sleep, sleep latency, subjective sleepiness, and biological sex were all significant moderators of the overall effect. In conclusion, the current meta-analysis is the first comprehensive review to provide evidence that short-term sleep restriction significantly impairs waking neurocognitive functioning. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fast changes in chemical composition and size distribution of fine particles during the near-field transport of industrial plumes.

PubMed

Marris, Hélène; Deboudt, Karine; Augustin, Patrick; Flament, Pascal; Blond, François; Fiani, Emmanuel; Fourmentin, Marc; Delbarre, Hervé

2012-06-15

Aerosol sampling was performed inside the chimneys and in the close environment of a FeMn alloys manufacturing plant. The number size distributions show a higher abundance of ultrafine aerosols (10-100 nm) inside the plume than upwind of the plant, indicating the emissions of nanoparticles by the industrial process. Individual analysis of particles collected inside the plume shows a high proportion of metal bearing particles (Mn-/Fe-) consisting essentially of internally mixed aluminosilicate and metallic compounds. These particles evolve rapidly (in a few minutes) after emission by adsorption of VOC gas and sulfuric acid emitted by the plant but also by agglomeration with pre-existing particles. At the moment, municipalities require a monitoring of industrial emissions inside the chimneys from manufacturers. However those measures are insufficient to report such rapid changes in chemical composition and thus to evaluate the real impact of industrial plumes in the close environment of plants (when those particles leave the industrial site). Consequently, environmental authorities will have to consider such fast evolutions and then to adapt future regulations on air pollution sources. Copyright © 2012 Elsevier B.V. All rights reserved.

An overview of meta-analysis for clinicians.

PubMed

Lee, Young Ho

2018-03-01

The number of medical studies being published is increasing exponentially, and clinicians must routinely process large amounts of new information. Moreover, the results of individual studies are often insufficient to provide confident answers, as their results are not consistently reproducible. A meta-analysis is a statistical method for combining the results of different studies on the same topic and it may resolve conflicts among studies. Meta-analysis is being used increasingly and plays an important role in medical research. This review introduces the basic concepts, steps, advantages, and caveats of meta-analysis, to help clinicians understand it in clinical practice and research. A major advantage of a meta-analysis is that it produces a precise estimate of the effect size, with considerably increased statistical power, which is important when the power of the primary study is limited because of a small sample size. A meta-analysis may yield conclusive results when individual studies are inconclusive. Furthermore, meta-analyses investigate the source of variation and different effects among subgroups. In summary, a meta-analysis is an objective, quantitative method that provides less biased estimates on a specific topic. Understanding how to conduct a meta-analysis aids clinicians in the process of making clinical decisions.

How large are the consequences of covariate imbalance in cluster randomized trials: a simulation study with a continuous outcome and a binary covariate at the cluster level.

PubMed

Moerbeek, Mirjam; van Schie, Sander

2016-07-11

The number of clusters in a cluster randomized trial is often low. It is therefore likely random assignment of clusters to treatment conditions results in covariate imbalance. There are no studies that quantify the consequences of covariate imbalance in cluster randomized trials on parameter and standard error bias and on power to detect treatment effects. The consequences of covariance imbalance in unadjusted and adjusted linear mixed models are investigated by means of a simulation study. The factors in this study are the degree of imbalance, the covariate effect size, the cluster size and the intraclass correlation coefficient. The covariate is binary and measured at the cluster level; the outcome is continuous and measured at the individual level. The results show covariate imbalance results in negligible parameter bias and small standard error bias in adjusted linear mixed models. Ignoring the possibility of covariate imbalance while calculating the sample size at the cluster level may result in a loss in power of at most 25 % in the adjusted linear mixed model. The results are more severe for the unadjusted linear mixed model: parameter biases up to 100 % and standard error biases up to 200 % may be observed. Power levels based on the unadjusted linear mixed model are often too low. The consequences are most severe for large clusters and/or small intraclass correlation coefficients since then the required number of clusters to achieve a desired power level is smallest. The possibility of covariate imbalance should be taken into account while calculating the sample size of a cluster randomized trial. Otherwise more sophisticated methods to randomize clusters to treatments should be used, such as stratification or balance algorithms. All relevant covariates should be carefully identified, be actually measured and included in the statistical model to avoid severe levels of parameter and standard error bias and insufficient power levels.

No independent association between insufficient sleep and childhood obesity in the National Survey of Children's Health.

PubMed

Hassan, Fauziya; Davis, Matthew M; Chervin, Ronald D

2011-04-15

Prior studies have supported an association between insufficient sleep and childhood obesity, but most have not examined nationally representative samples or considered potential sociodemographic confounders. The main objective of this study was to use a large, nationally representative dataset to examine the possibility that insufficient sleep is associated with obesity in children, independent of sociodemographic factors. The National Survey of Children's Health is a national survey of U.S. households contacted by random digit dialing. In 2003, caregivers of 102,353 US children were surveyed. Age- and sex-specific body mass index (BMI) based on parental report of child height and weight, was available for 81,390 children aged 6-17 years. Caregivers were asked, "How many nights of sufficient sleep did your child have in the past week?" The odds of obesity (BMI ≥ 95th percentile) versus healthy weight (BMI 5th-84th percentile) was regressed on reported nights of sufficient sleep per week (categorized as 0-2, 3-5, or 6-7). Sociodemographic variables included gender, race, household education, and family income. Analyses incorporated sampling weights to derive nationally representative estimates for a 2003 population of 34 million youth. Unadjusted bivariate analyses indicated that children aged 6-11 years with 0-2 nights of sufficient sleep, in comparison to those with 6-7 nights, were more likely to be obese (OR = 1.7, 95% CI [1.2-2.3]). Among children aged 12-17 years, odds of obesity were lower among children with 3-5 nights of sufficient sleep in comparison to those with 6-7 nights (0.8, 95% CI: 0.7-0.9). However, in both age groups, adjustment for race/ethnicity, gender, family income, and household education left no remaining statistical significance for the association between sufficient nights of sleep and BMI. In this national sample, insufficient sleep, as judged by parents, is inconsistently associated with obesity in bivariate analyses, and not associated with obesity after adjustment for sociodemographic variables. These findings from a nationally representative sample are necessarily subject to parental perceptions, but nonetheless serve as an important reminder that the role of insufficient sleep in the childhood obesity epidemic remains unproven.

Analysis methods for Kevlar shield response to rotor fragments

NASA Technical Reports Server (NTRS)

Gerstle, J. H.

1977-01-01

Several empirical and analytical approaches to rotor burst shield sizing are compared and principal differences in metal and fabric dynamic behavior are discussed. The application of transient structural response computer programs to predict Kevlar containment limits is described. For preliminary shield sizing, present analytical methods are useful if insufficient test data for empirical modeling are available. To provide other information useful for engineering design, analytical methods require further developments in material characterization, failure criteria, loads definition, and post-impact fragment trajectory prediction.

21 CFR 529.1940 - Progesterone intravaginal inserts.

Code of Federal Regulations, 2013 CFR

2013-04-01

... synchronization of estrus in suckled beef cows and replacement beef and dairy heifers; for advancement of first postpartum estrus in suckled beef cows; and for advancement of first pubertal estrus in replacement beef.... Do not use in beef or dairy heifers of insufficient size or age for breeding or in animals with...

21 CFR 529.1940 - Progesterone intravaginal inserts.

Code of Federal Regulations, 2012 CFR

2012-04-01

... synchronization of estrus in suckled beef cows and replacement beef and dairy heifers; for advancement of first postpartum estrus in suckled beef cows; and for advancement of first pubertal estrus in replacement beef.... Do not use in beef or dairy heifers of insufficient size or age for breeding or in animals with...

21 CFR 529.1940 - Progesterone intravaginal inserts.

Code of Federal Regulations, 2011 CFR

2011-04-01

... synchronization of estrus in suckled beef cows and replacement beef and dairy heifers; for advancement of first postpartum estrus in suckled beef cows; and for advancement of first pubertal estrus in replacement beef.... Do not use in beef or dairy heifers of insufficient size or age for breeding or in animals with...

Polymorphism influences singlet fission rates in tetracene thin films

DOE PAGES

Arias, Dylan H.; Ryerson, Joseph L.; Cook, Jasper D.; ...

2015-11-06

Here, we report the effect of crystal structure and crystallite grain size on singlet fission (SF) in polycrystalline tetracene, one of the most widely studied SF and organic semiconductor materials. SF has been comprehensively studied in one polymoprh (Tc I), but not in the other, less stable polymorph (Tc II). Using carefully controlled thermal evaporation deposition conditions and high sensitivity ultrafast transient absorption spectroscopy, we found that for large crystallite size samples, SF in nearly pure Tc II films is significantly faster than SF in Tc I films. We also discovered that crystallite size has a minimal impact on themore » SF rate in Tc II films, but a significant influence in Tc I films. Large crystallites exhibit SF times of 125 ps and 22 ps in Tc I and Tc II, respectively, whereas small crystallites have SF times of 31 ps and 33 ps. Our results demonstrate first, that attention must be paid to polymorphism in obtaining a self-consistent rate picture for SF in tetracene and second, that control of polymorphism can play a significant role towards achieving a mechanistic understanding of SF in polycrystalline systems. In this latter context we show that conventional theory based on non-covalent tetracene couplings is insufficient, thus highlighting the need for models that capture the delocalized and highly mobile nature of excited states in elucidating the full photophysical picture.« less

[Outpatient physiotherapy for patients with knee pain in northern Germany].

PubMed

Karstens, S; Froböse, I; Weiler, S W

2014-10-01

Physiotherapy, in comparison to occupational therapy and speech therapy, is the most frequently prescribed treatment in Germany. Nationally there is only scarce information available on indications, treatment approaches and development of health condition throughout therapy. Present work encompasses only small sample sizes and insufficient follow-up periods. To describe, how patients with knee complaints are treated based on a physiotherapy referral and how their health condition changes during therapy. A descriptive-exploratory secondary analysis of data from a prospective multicentre observational study was conducted. The Bother index of the Musculoskeletal Function Assessment Questionnaire (German, 16-Item version) and an 11-step box scale on pain intensity were utilised as outcome criteria. Data of 160 patients, age 47.4 (SD 10.8), 51% female, approximately 51% with previous arthroscopy, were analysed. The response rate 6 months after therapy approximately amounted to 50%. Main therapy approaches were strengthening, stretching and manual therapy, combined with home exercises. Impairment in daily life as well as pain improved substantially during therapy (SES range 0.6-1.75). The conducted study brought up insights for physiotherapy health service for pa-tients with cartilage or meniscal problems, based on a sample size not accessible for Germany before. After reviewing the international literature it may be assumed, that the clearly active character of the therapy and the combination of different treatment approaches are of relevance for the presented reduction of impairment in daily life. © Georg Thieme Verlag KG Stuttgart · New York.

Association of Postpartum Maternal Morbidities with Children's Mental, Psychomotor and Language Development in Rural Bangladesh

PubMed Central

Tofail, F.; Hilaly, A.; Mehrin, F.; Shiraji, S.; Banu, S.; Huda, S.N.

2012-01-01

Little is known from developing countries about the effects of maternal morbidities diagnosed in the postpartum period on children's development. The study aimed to document the relationships of such morbidities with care-giving practices by mothers, children's developmental milestones and their language, mental and psychomotor development. Maternal morbidities were identified through physical examination at 6-9 weeks postpartum (n=488). Maternal care-giving practices and postnatal depression were assessed also at 6-9 weeks postpartum. Children's milestones of development were measured at six months, and their mental (MDI) and psychomotor (PDI) development, language comprehension and expression, and quality of psychosocial stimulation at home were assessed at 12 months. Several approaches were used for identifying the relationships among different maternal morbidities, diagnosed by physicians, with children's development. After controlling for the potential confounders, maternal anaemia diagnosed postpartum showed a small but significantly negative effect on children's language expression while the effects on language comprehension did not reach the significance level (p=0.085). Children's development at 12 months was related to psychosocial stimulation at home, nutritional status, education of parents, socioeconomic status, and care-giving practices of mothers at six weeks of age. Only a few mothers experienced each specific morbidity, and with the exception of anaemia, the sample-size was insufficient to make a conclusion regarding each specific morbidity. Further research with a sufficient sample-size of individual morbidities is required to determine the association of postpartum maternal morbidities with children's development. PMID:22838161

Using re-randomization to increase the recruitment rate in clinical trials - an assessment of three clinical areas.

PubMed

Kahan, Brennan C

2016-12-13

Patient recruitment in clinical trials is often challenging, and as a result, many trials are stopped early due to insufficient recruitment. The re-randomization design allows patients to be re-enrolled and re-randomized for each new treatment episode that they experience. Because it allows multiple enrollments for each patient, this design has been proposed as a way to increase the recruitment rate in clinical trials. However, it is unknown to what extent recruitment could be increased in practice. We modelled the expected recruitment rate for parallel-group and re-randomization trials in different settings based on estimates from real trials and datasets. We considered three clinical areas: in vitro fertilization, severe asthma exacerbations, and acute sickle cell pain crises. We compared the two designs in terms of the expected time to complete recruitment, and the sample size recruited over a fixed recruitment period. Across the different scenarios we considered, we estimated that re-randomization could reduce the expected time to complete recruitment by between 4 and 22 months (relative reductions of 19% and 45%), or increase the sample size recruited over a fixed recruitment period by between 29% and 171%. Re-randomization can increase recruitment most for trials with a short follow-up period, a long trial recruitment duration, and patients with high rates of treatment episodes. Re-randomization has the potential to increase the recruitment rate in certain settings, and could lead to quicker and more efficient trials in these scenarios.

Cervical cerclage placement decreases local levels of proinflammatory cytokines in patients with cervical insufficiency.

PubMed

Monsanto, Stephany P; Daher, Silvia; Ono, Erika; Pendeloski, Karen Priscilla Tezotto; Trainá, Évelyn; Mattar, Rosiane; Tayade, Chandrakant

2017-10-01

Cervical insufficiency is characterized by premature, progressive dilation and shortening of the cervix during pregnancy. If left unattended, this can lead to the prolapse and rupture of the amniotic membrane, which usually results in midtrimester pregnancy loss or preterm birth. Previous studies have shown that proinflammatory cytokines such as interleukin-1β, interleukin-6, interleukin-8, and tumor necrosis factor alpha are up-regulated in normal parturition but are also associated with preterm birth. Studies evaluating such markers in patients with cervical insufficiency have evaluated only their diagnostic potential. Even fewer studies have studied them within the context of cerclage surgery. The objective of the study was to evaluate the impact of local and systemic inflammatory markers on the pathogenesis of cervical insufficiency and the effect of cerclage surgery on the local immune microenvironment of women with cervical insufficiency. We recruited 28 pregnant women (12-20 weeks' gestation) diagnosed with insufficiency and referred for cerclage surgery and 19 gestational age-matched normal pregnant women as controls. Serum and cervicovaginal fluid samples were collected before and after cerclage surgery and during a routine checkup for normal women and analyzed using a targeted 13-plex proinflammatory cytokine assay. Before surgery, patients with cervical insufficiency had higher levels of interleukin-1β, interleukin-6, interleukin-12, monocyte chemoattractant protein-1 and tumor necrosis factor alpha in cervicovaginal fluid compared to controls, but after surgery, these differences disappeared. No differences were found in serum of insufficiency versus control women. In patients with insufficiency, the levels of interleukin-1β, interleukin-6, interleukin-8, monocyte chemoattractant protein-1, and interferon gamma in cervicovaginal fluid declined significantly after cerclage compared with before intervention, but these changes were not detected in serum. Compared with normal women, patients with cervical insufficiency have elevated levels of proinflammatory cytokines in cervicovaginal fluid but not in serum, suggesting a dysregulation of the local immune environment. Cerclage intervention led to a significant decline in these proinflammatory cytokines, suggesting that cerclage may help reduce local inflammation in cervical insufficiency. Copyright © 2017 Elsevier Inc. All rights reserved.

Seabed texture and composition changes offshore of Port Royal Sound, South Carolina before and after the dredging for beach nourishment

NASA Astrophysics Data System (ADS)

Xu, Kehui; Sanger, Denise; Riekerk, George; Crowe, Stacie; Van Dolah, Robert F.; Wren, P. Ansley; Ma, Yanxia

2014-08-01

Beach nourishment has been a strategy widely used to slow down coastal erosion in many beaches around the world. The dredging of sand at the borrow site, however, can have complicated physical, geological and ecological impacts. Our current knowledge is insufficient to make accurate predictions of sediment infilling in many dredging pits due to lack of detailed sediment data. Two sites in the sandy shoal southeast of Port Royal Sound (PRS) of South Carolina, USA, were sampled 8 times from April 2010 to March 2013; one site (defined as 'borrow site') was 2 km offshore and used as the dredging site for beach nourishment of nearby Hilton Head Island in Beaufort County, South Carolina, and the other site (defined as 'reference site') was 10 km offshore and not directly impacted by the dredging. A total of 184 surficial sediment samples were collected randomly at two sites during 8 sampling periods. Most sediments were fine sand, with an average grain size of 2.3 phi and an organic matter content less than 2%. After the dredging in December 2011-January 2012, sediments at the borrow site became finer, changing from 1.0 phi to 2.3 phi, and carbonate content decreased from 10% to 4%; changes in mud content and organic matter were small. Compared with the reference site, the borrow site experienced larger variations in mud and carbonate content. An additional 228 sub-samples were gathered from small cores collected at 5 fixed stations in the borrow site and 1 fixed station at the reference site 0, 3, 6, 9, and 12 months after the dredging; these down-core sub-samples were divided into 1-cm slices and analyzed using a laser diffraction particle size analyzer. Most cores were uniform vertically and consisted of fine sand with well to moderately well sorting and nearly symmetrical averaged skewness. Based on the analysis of grain size populations, 2 phi- and 3 phi-sized sediments were the most dynamic sand fractions in PRS. Mud deposition on shoals offshore of PRS presumably happens when offshore mud transport is prevalent and there is a following rapid sand accumulation to bury the mud. However, in this borrow site there was very little accumulation of mud. This will allow the site to be used in future nourishment projects presuming no accumulation of mud occurs in the future.

Hesperetin-loaded lipid-core nanocapsules in polyamide: a new textile formulation for topical drug delivery

PubMed Central

Menezes, Paula dos Passos; Frank, Luiza Abrahão; Lima, Bruno dos Santos; de Carvalho, Yasmim Maria Barbosa Gomes; Serafini, Mairim Russo; Quintans-Júnior, Lucindo José; Pohlmann, Adriana Raffin; Guterres, Sílvia Stanisçuaski; Araújo, Adriano Antunes de Souza

2017-01-01

Chronic venous insufficiency is characterized by chronic reflux disorder of blood from the peripheral to the central vein, with subsequent venous hypertension and resulting changes in the skin. Traditionally, nonsurgical treatments relied on the use of compression therapy, and more recently a variety of flavonoids have been shown to have positive effects. There have also been developments of more effective drug delivery systems using various textiles and nanotechnology to provide new therapeutic options. Our objective was to use nanotechnology to develop a new formulation containing hesperetin (Hst), a substance not previously used in the treatment of chronic venous insufficiency, impregnated into textile fibers as a possible alternative treatment of venous diseases. We prepared the nanocapsules using the interfacial deposition of preformed polymer method with an Hst concentration of 0.5 mg/mL and then characterized the size and distribution of particles. To quantify the Hst in the samples, we developed an analytical method using high-performance liquid chromatography. Studies of encapsulation efficiency (98.81%±0.28%), microscopy, drug release (free-Hst: 104.96%±12.83%; lipid-core nanocapsule-Hst: 69.90%±1.33%), penetration/permeation, drug content (0.46±0.01 mg/mL) and the effect of washing the textile after drug impregnation were performed as part of the study. The results showed that nanoparticles of a suitable size and distribution with controlled release of the drug and penetration/permeation into the skin layers were achieved. Furthermore, it was established that polyamide was able to hold more of the drug, with a 2.54 times higher content than the cotton fiber; after one wash and after five washes, this relation was 2.80 times higher. In conclusion, this is a promising therapeutic alternative to be further studied in clinical trials. PMID:28352176

Specific Radiological Imaging Findings in Patients With Hereditary Pancreatitis During a Long Follow-up of Disease.

PubMed

van Esch, Aura A J; Drenth, Joost P H; Hermans, John J

2017-03-01

Hereditary pancreatitis (HP) is characterized by recurrent episodes of inflammation of the pancreas. Radiological imaging is used to diagnose HP and to monitor complications. The aim of this study was to describe specific imaging findings in HP. We retrospectively collected data of HP patients with serial imaging and reviewed all radiological imaging studies (transabdominal ultrasonography, computed tomography, and magnetic resonance imaging). We included 15 HP patients, with a mean age of 32.5 years (range, 9-61 years) and mean disease duration of 24.1 years (range, 6-42 years). In total, 152 imaging studies were reviewed. Seventy-three percent of patients had a dilated main pancreatic duct (MPD) (width 3.5-18 mm). The MPD varied in size during disease course, with temporary reduction in diameter after drainage procedures. A severe dilated MPD (>10 mm) often coincided with presence of intraductal calcifications (size, 1-12 mm). In 73% of patients, pancreatic parenchyma atrophy occurred, which did not correlate with presence of exocrine or endocrine insufficiency. In HP, the MPD diameter increases with time, mostly without dilated side branches, and is often accompanied by large intraductal calcifications. The size of the MPD is independent of disease state. Atrophy of pancreatic parenchyma is not correlated with exocrine or endocrine insufficiency.

Determination of a Screening Metric for High Diversity DNA Libraries.

PubMed

Guido, Nicholas J; Handerson, Steven; Joseph, Elaine M; Leake, Devin; Kung, Li A

2016-01-01

The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.

Substrate conditions and abundance of lake trout eggs in a traditional spawning area in southeastern Lake Michigan

USGS Publications Warehouse

Dorr, John A.; O'Connor, Daniel V.; Foster, Neal R.; Jude, David J.

1981-01-01

Spawning by planted lake trout (Salvelinus namaycush) was documented by sampling with a diver-assisted pump in a traditional spawning area in southeastern Lake Michigan near Saugatuck, Michigan in mid-November in 1978 and 1979. Bottom depths at the 11 locations sampled ranged from 3 to 12 m and substrate size from boulders to sand. Periphyton (Cladophora and associated biota) was several millimeters thick at most stations but sparse at the shallowest. The most eggs recovered from a single sample occurred at the shallowest depth (3 m). In both years, some of the small numbers of eggs collected (9 in 1978, 14 in 1979) were alive and fertilized. Laboratory incubation of viable eggs resulted in successful hatching of larvae. When compared with egg densities measured at spawning sites used by self-sustaining populations of lake trout in other lakes, densities in the study are (0-13/m2) appeared to be critically low. Insufficient numbers of eggs, combined with harsh incubation conditions (turbulence, ice scour, sedimentation), were implicated as prime causes for lake trout reproductive failure in the study area, although other factors, such as inappropriate spawning behavior (selection of suboptimal spawning location, depth, or substrate) also may have reduced survival of eggs and larvae.

Quality-assurance data for routine water analyses by the U.S. Geological Survey Laboratory in Troy, New York—July 1995 through June 1997

USGS Publications Warehouse

Lincoln, Tricia A.; Horan-Ross, Debra A.; McHale, Michael R.; Lawrence, Gregory B.

2005-01-01

Results from blind reference-sample analyses indicated that data-quality objectives were met by at least 90 percent of the calcium, pH, potassium, and sodium samples. Data-quality objectives were met by 77 percent of the chloride samples, 83 percent of the magnesium samples, and 80 percent of the sulfate samples. There is insufficient data to evaluate the specific conductance samples.

Quantitative Assessment of Molecular Dynamics Sampling for Flexible Systems.

PubMed

Nemec, Mike; Hoffmann, Daniel

2017-02-14

Molecular dynamics (MD) simulation is a natural method for the study of flexible molecules but at the same time is limited by the large size of the conformational space of these molecules. We ask by how much the MD sampling quality for flexible molecules can be improved by two means: the use of diverse sets of trajectories starting from different initial conformations to detect deviations between samples and sampling with enhanced methods such as accelerated MD (aMD) or scaled MD (sMD) that distort the energy landscape in controlled ways. To this end, we test the effects of these approaches on MD simulations of two flexible biomolecules in aqueous solution, Met-Enkephalin (5 amino acids) and HIV-1 gp120 V3 (a cycle of 35 amino acids). We assess the convergence of the sampling quantitatively with known, extensive measures of cluster number N c and cluster distribution entropy S c and with two new quantities, conformational overlap O conf and density overlap O dens , both conveniently ranging from 0 to 1. These new overlap measures quantify self-consistency of sampling in multitrajectory MD experiments, a necessary condition for converged sampling. A comprehensive assessment of sampling quality of MD experiments identifies the combination of diverse trajectory sets and aMD as the most efficient approach among those tested. However, analysis of O dens between conventional and aMD trajectories also reveals that we have not completely corrected aMD sampling for the distorted energy landscape. Moreover, for V3, the courses of N c and O dens indicate that much higher resources than those generally invested today will probably be needed to achieve convergence. The comparative analysis also shows that conventional MD simulations with insufficient sampling can be easily misinterpreted as being converged.

The Proteomic Analysis of Pancreatic Exocrine Insufficiency Protein Marker in Type 2 Diabetes Mellitus Patients

NASA Astrophysics Data System (ADS)

Srihardyastutie, Arie; Soeatmadji, DW; Fatchiyah; Aulanni'am

2018-01-01

Type 2 Diabetes Mellitus (T2D) is the vast majority case of diabetes. Patient with T2D is at higher risk for developing acute or chronic pancreatitis. Prolonged hyperglycemia results in damages to tissue, which also causes dysfunctions of some organ systems, including enzyme or hormone secretions. Commonly, dysfunction or insufficiency of pancreatic exocrine is evaluated by increasing activity of serum pancreatic enzyme, such as amylase and lipase. Although incidence of pancreatitis was found in Indonesian T2D, the pathogenic mechanism still unclear. The aim of this study was to characterize the marker protein that indicated the correlation of pancreatic exocrine insufficiency with progression of T2D. Proteomic analysis using LC-MS/MS was used in identification and characterization of protein marker which indicates insufficiency pancreatic exocrine. First step, protein profile was analyzed by SDS-PAGE methods using serum sample of T2D compared with normal or healthy control, as negative control, and pancreatitis patients, as positive control. Protein with 18 kDa was found as a candidate protein marker which indicated the pancreatic exocrine insufficiency in T2D. The further identification of that protein using LC-MS/MS showed 4 peptide fragments. In silico analysis of the peptide fragment indicated the correlation of pancreatic exocrine insufficiency with progression of T2D was METTL10 - methyltransferase like protein-10.

Review of atrazine sampling by polar organic chemical integrative samplers and Chemcatcher.

PubMed

Booij, Kees; Chen, Sunmao

2018-04-24

A key success factor for the performance of passive samplers is the proper calibration of sampling rates. Sampling rates for a wide range of polar organic compounds are available for Chemcatchers and polar organic chemical integrative samplers (POCIS), but the mechanistic models that are needed to understand the effects of exposure conditions on sampling rates need improvement. Literature data on atrazine sampling rates by these samplers were reviewed with the aim of assessing what can be learned from literature reports of this well-studied compound and identifying knowledge gaps related to the effects of flow and temperature. The flow dependency of sampling rates could be described by a mass transfer resistance model with 1 (POCIS) or 2 (Chemcatcher) adjustable parameters. Literature data were insufficient to evaluate the temperature effect on the sampling rates. An evaluation of reported sampler configurations showed that standardization of sampler design can be improved: for POCIS with respect to surface area and sorbent mass, and for Chemcatcher with respect to housing design. Several reports on atrazine sampling could not be used because the experimental setups were insufficiently described with respect to flow conditions. Recommendations are made for standardization of sampler layout and documentation of flow conditions in calibration studies. Environ Toxicol Chem 2018;9999:1-13. © 2018 SETAC. © 2018 SETAC.

Spatial patterns of throughfall isotopic composition at the event and seasonal timescales

NASA Astrophysics Data System (ADS)

Allen, Scott T.; Keim, Richard F.; McDonnell, Jeffrey J.

2015-03-01

Spatial variability of throughfall isotopic composition in forests is indicative of complex processes occurring in the canopy and remains insufficiently understood to properly characterize precipitation inputs to the catchment water balance. Here we investigate variability of throughfall isotopic composition with the objectives: (1) to quantify the spatial variability in event-scale samples, (2) to determine if there are persistent controls over the variability and how these affect variability of seasonally accumulated throughfall, and (3) to analyze the distribution of measured throughfall isotopic composition associated with varying sampling regimes. We measured throughfall over two, three-month periods in western Oregon, USA under a Douglas-fir canopy. The mean spatial range of δ18O for each event was 1.6‰ and 1.2‰ through Fall 2009 (11 events) and Spring 2010 (7 events), respectively. However, the spatial pattern of isotopic composition was not temporally stable causing season-total throughfall to be less variable than event throughfall (1.0‰; range of cumulative δ18O for Fall 2009). Isotopic composition was not spatially autocorrelated and not explained by location relative to tree stems. Sampling error analysis for both field measurements and Monte-Carlo simulated datasets representing different sampling schemes revealed the standard deviation of differences from the true mean as high as 0.45‰ (δ18O) and 1.29‰ (d-excess). The magnitude of this isotopic variation suggests that small sample sizes are a source of substantial experimental error.

Risk factors and preventive interventions for Alzheimer disease: state of the science.

PubMed

Daviglus, Martha L; Plassman, Brenda L; Pirzada, Amber; Bell, Carl C; Bowen, Phyllis E; Burke, James R; Connolly, E Sander; Dunbar-Jacob, Jacqueline M; Granieri, Evelyn C; McGarry, Kathleen; Patel, Dinesh; Trevisan, Maurizio; Williams, John W

2011-09-01

Numerous studies have investigated risk factors for Alzheimer disease (AD). However, at a recent National Institutes of Health State-of-the-Science Conference, an independent panel found insufficient evidence to support the association of any modifiable factor with risk of cognitive decline or AD. To present key findings for selected factors and AD risk that led the panel to their conclusion. An evidence report was commissioned by the Agency for Healthcare Research and Quality. It included English-language publications in MEDLINE and the Cochrane Database of Systematic Reviews from 1984 through October 27, 2009. Expert presentations and public discussions were considered. Study inclusion criteria for the evidence report were participants aged 50 years and older from general populations in developed countries; minimum sample sizes of 300 for cohort studies and 50 for randomized controlled trials; at least 2 years between exposure and outcome assessment; and use of well-accepted diagnostic criteria for AD. Included studies were evaluated for eligibility and data were abstracted. Quality of overall evidence for each factor was summarized as low, moderate, or high. Diabetes mellitus, hyperlipidemia in midlife, and current tobacco use were associated with increased risk of AD, and Mediterranean-type diet, folic acid intake, low or moderate alcohol intake, cognitive activities, and physical activity were associated with decreased risk. The quality of evidence was low for all of these associations. Currently, insufficient evidence exists to draw firm conclusions on the association of any modifiable factors with risk of AD.

The interplay of homing and dispersal in green turtles: a focus on the southwestern atlantic.

PubMed

Naro-Maciel, Eugenia; Bondioli, Ana Cristina Vigliar; Martin, Meredith; de Pádua Almeida, Antônio; Baptistotte, Cecília; Bellini, Claudio; Marcovaldi, Maria Ângela; Santos, Armando José Barsante; Amato, George

2012-01-01

Current understanding of spatial ecology is insufficient in many threatened marine species, failing to provide a solid basis for conservation and management. To address this issue for globally endangered green turtles, we investigated their population distribution by sequencing a mitochondrial control region segment from the Rocas Atoll courtship area (n = 30 males) and four feeding grounds (FGs) in Brazil (n = 397), and compared our findings to published data (n (nesting) = 1205; n (feeding) = 1587). At Rocas Atoll, the first Atlantic courtship area sequenced to date, we found males were differentiated from local juveniles but not from nesting females. In combination with tag data, this indicates possible male philopatry. The most common haplotypes detected at the study sites were CMA-08 and CMA-05, and significant temporal variation was not revealed. Although feeding grounds were differentiated overall, intra-regional structure was less pronounced. Ascension was the primary natal source of the study FGs, with Surinam and Trindade as secondary sources. The study clarified the primary connectivity between Trindade and Brazil. Possible linkages to African populations were considered, but there was insufficient resolution to conclusively determine this connection. The distribution of FG haplotype lineages was nonrandom and indicative of regional clustering. The study investigated impacts of population size, geographic distance, ocean currents, and juvenile natal homing on connectivity, addressed calls for increased genetic sampling in the southwestern Atlantic, and provided data important for conservation of globally endangered green turtles.

Active Video Games in Schools and Effects on Physical Activity and Health: A Systematic Review.

PubMed

Norris, Emma; Hamer, Mark; Stamatakis, Emmanuel

2016-05-01

To assess the quality of evidence for the effects of school active video game (AVG) use on physical activity and health outcomes. Online databases (ERIC, PsycINFO, PubMed, SPORTDiscus, and Web of Science) and gray literature were searched. Inclusion criteria were the use of AVGs in school settings as an intervention; assessment of at least 1 health or physical activity outcome; and comparison of outcomes with either a control group or comparison phase. Studies featuring AVGs within complex interventions were excluded. Study quality was assessed using the Effective Public Health Practice Project tool. Twenty-two reports were identified: 11 assessed physical activity outcomes only, 5 assessed motor skill outcomes only, and 6 assessed both physical activity and health outcomes. Nine out of 14 studies found greater physical activity in AVG sessions compared with controls; mostly assessed by objective measures in school time only. Motor skills were found to improve with AVGs vs controls in all studies but not compared with other motor skill interventions. Effects of AVGs on body composition were mixed. Study quality was low in 16 studies and moderate in the remaining 6, with insufficient detail given on blinding, participation rates, and confounding variables. There is currently insufficient evidence to recommend AVGs as efficacious health interventions within schools. Higher quality AVG research utilizing randomized controlled trial designs, larger sample sizes, and validated activity measurements beyond the school day is needed. Copyright © 2016 Elsevier Inc. All rights reserved.

PROLONGED FLOODING DECREASED STEM DENSITY, TREE SIZE AND SHIFTED COMPOSITION TOWARDS CLONAL SPECIES IN A CENTRAL FLORIDA HARDWOOD SWAMP

EPA Science Inventory

Human modifications of the landscape often cause changes in regional hydrology that, in turn, can result in the alteration of wetland hydrology. Altering hydrology can lead to hydroperiods that have prolonged or insufficient hydration, which can often cause changes in plant comm...

Characterizing and predicting species distributions across environments and scales: Argentine ant occurrences in the eye of the beholder

USGS Publications Warehouse

Menke, S.B.; Holway, D.A.; Fisher, R.N.; Jetz, W.

2009-01-01

Aim: Species distribution models (SDMs) or, more specifically, ecological niche models (ENMs) are a useful and rapidly proliferating tool in ecology and global change biology. ENMs attempt to capture associations between a species and its environment and are often used to draw biological inferences, to predict potential occurrences in unoccupied regions and to forecast future distributions under environmental change. The accuracy of ENMs, however, hinges critically on the quality of occurrence data. ENMs often use haphazardly collected data rather than data collected across the full spectrum of existing environmental conditions. Moreover, it remains unclear how processes affecting ENM predictions operate at different spatial scales. The scale (i.e. grain size) of analysis may be dictated more by the sampling regime than by biologically meaningful processes. The aim of our study is to jointly quantify how issues relating to region and scale affect ENM predictions using an economically important and ecologically damaging invasive species, the Argentine ant (Linepithema humile). Location: California, USA. Methods: We analysed the relationship between sampling sufficiency, regional differences in environmental parameter space and cell size of analysis and resampling environmental layers using two independently collected sets of presence/absence data. Differences in variable importance were determined using model averaging and logistic regression. Model accuracy was measured with area under the curve (AUC) and Cohen's kappa. Results: We first demonstrate that insufficient sampling of environmental parameter space can cause large errors in predicted distributions and biological interpretation. Models performed best when they were parametrized with data that sufficiently sampled environmental parameter space. Second, we show that altering the spatial grain of analysis changes the relative importance of different environmental variables. These changes apparently result from how environmental constraints and the sampling distributions of environmental variables change with spatial grain. Conclusions: These findings have clear relevance for biological inference. Taken together, our results illustrate potentially general limitations for ENMs, especially when such models are used to predict species occurrences in novel environments. We offer basic methodological and conceptual guidelines for appropriate sampling and scale matching. ?? 2009 The Authors Journal compilation ?? 2009 Blackwell Publishing.

Evaluation of an in-practice wet-chemistry analyzer using canine and feline serum samples.

PubMed

Irvine, Katherine L; Burt, Kay; Papasouliotis, Kostas

2016-01-01

A wet-chemistry biochemical analyzer was assessed for in-practice veterinary use. Its small size may mean a cost-effective method for low-throughput in-house biochemical analyses for first-opinion practice. The objectives of our study were to determine imprecision, total observed error, and acceptability of the analyzer for measurement of common canine and feline serum analytes, and to compare clinical sample results to those from a commercial reference analyzer. Imprecision was determined by within- and between-run repeatability for canine and feline pooled samples, and manufacturer-supplied quality control material (QCM). Total observed error (TEobs) was determined for pooled samples and QCM. Performance was assessed for canine and feline pooled samples by sigma metric determination. Agreement and errors between the in-practice and reference analyzers were determined for canine and feline clinical samples by Bland-Altman and Deming regression analyses. Within- and between-run precision was high for most analytes, and TEobs(%) was mostly lower than total allowable error. Performance based on sigma metrics was good (σ > 4) for many analytes and marginal (σ > 3) for most of the remainder. Correlation between the analyzers was very high for most canine analytes and high for most feline analytes. Between-analyzer bias was generally attributed to high constant error. The in-practice analyzer showed good overall performance, with only calcium and phosphate analyses identified as significantly problematic. Agreement for most analytes was insufficient for transposition of reference intervals, and we recommend that in-practice-specific reference intervals be established in the laboratory. © 2015 The Author(s).

A prospective assessment of the natural course of the exocrine pancreatic function in patients with a pancreatic head tumor.

PubMed

Sikkens, Edmée C M; Cahen, Djuna L; de Wit, Jill; Looman, Caspar W N; van Eijck, Casper; Bruno, Marco J

2014-01-01

In cancer of the pancreatic head region, exocrine insufficiency is a well-known complication, leading to steatorrhea, weight loss, and malnutrition. Its presence is frequently overlooked, however, because the primary attention is focused on cancer treatment. To date, the risk of developing exocrine insufficiency is unspecified. Therefore, we assessed this function in patients with tumors of the pancreatic head, distal common bile duct, or ampulla of Vater. Between March 2010 and August 2012, we prospectively included patients diagnosed with cancer of the pancreatic head region at our tertiary center. To preclude the effect of a resection, we excluded operated patients. Each month, the exocrine function was determined with a fecal elastase test. Furthermore, endocrine function, steatorrhea-related symptoms, and body weight were evaluated. Patients were followed for 6 months, or until death. Thirty-two patients were included. The tumor was located in the pancreas in 75%, in the bile duct in 16%, and in the ampullary region in 9%, with a median size of 2.5 cm. At diagnosis, the prevalence of exocrine insufficiency was 66%, which increased to 92% after a median follow-up of 2 months (interquartile range, 1 to 4 mo). Most patients with cancer of the pancreatic head region were already exocrine insufficient at diagnosis, and within several months, this function was impaired in almost all cases. Given this high prevalence, physicians should be focused on diagnosing and treating exocrine insufficiency, to optimize the nutritional status and physical condition, especially for those patients undergoing palliative chemotherapy and/or radiotherapy.

Sampling for pharmaceuticals and personal care products (PPCPs) and illicit drugs in wastewater systems: are your conclusions valid? A critical review.

PubMed

Ort, Christoph; Lawrence, Michael G; Rieckermann, Jörg; Joss, Adriano

2010-08-15

The analysis of 87 peer-reviewed journal articles reveals that sampling for pharmaceuticals and personal care products (PPCPs) and illicit drugs in sewers and sewage treatment plant influents is mostly carried out according to existing tradition or standard laboratory protocols. Less than 5% of all studies explicitly consider internationally acknowledged guidelines or methods for the experimental design of monitoring campaigns. In the absence of a proper analysis of the system under investigation, the importance of short-term pollutant variations was typically not addressed. Therefore, due to relatively long sampling intervals, potentially inadequate sampling modes, or insufficient documentation, it remains unclear for the majority of reviewed studies whether observed variations can be attributed to "real" variations or if they simply reflect sampling artifacts. Based on results from previous and current work, the present paper demonstrates that sampling errors can lead to overinterpretation of measured data and ultimately, wrong conclusions. Depending on catchment size, sewer type, sampling setup, substance of interest, and accuracy of analytical method, avoidable sampling artifacts can range from "not significant" to "100% or more" for different compounds even within the same study. However, in most situations sampling errors can be reduced greatly, and sampling biases can be eliminated completely, by choosing an appropriate sampling mode and frequency. This is crucial, because proper sampling will help to maximize the value of measured data for the experimental assessment of the fate of PPCPs as well as for the formulation and validation of mathematical models. The trend from reporting presence or absence of a compound in "clean" water samples toward the quantification of PPCPs in raw wastewater requires not only sophisticated analytical methods but also adapted sampling methods. With increasing accuracy of chemical analyses, inappropriate sampling increasingly represents the major source of inaccuracy. A condensed step-by-step Sampling Guide is proposed as a starting point for future studies.

Concordance of vitamin D peripheral levels in infertile couples' partners.

PubMed

Paffoni, Alessio; Ferrari, Stefania; Mangiarini, Alice; Noli, Stefania; Bulfoni, Alessandro; Vigano, Paola; Parazzini, Fabio; Somigliana, Edgardo

2017-08-01

A large number of evidence supports the role of vitamin D insufficiency in both women and men infertility. However, no studies have evaluated the rate of concordance of vitamin D status between the partners. This finding might open new scenarios in the interpretation of the available data linking vitamin D insufficiency and infertility. In the present cross-sectional study, 103 consecutive infertile couples were recruited between April and May 2014. Both partners concomitantly provided a serum sample for the assessment of 25-hydroxy-vitamin D [25-(OH)-D]. Vitamin D insufficiency was defined as serum 25-(OH)-D <20 ng/ml. One hundred-fifty subjects (73 women and 77 males) were 25-(OH)-D insufficient, corresponding to a rate of 73%. Overall, concordance was observed in 73 couples (71%), thus higher than the expected 61% (0.732 + 0.272) based on chance (p = 0.007). The Pearson coefficient of correlation R2 between the partners of the couples was 0.52 (p < 0.001). No statistically significant differences emerged when evaluating the rate of 25-(OH)-D insufficiency according to the causes of infertility. Serum 25-(OH)-D correlates within the partners of infertile couples. Further evidence is warranted to determine the clinical relevance and possible clinical applications of this finding.

Association between self-reported sleep duration and dietary quality in European adolescents.

PubMed

Bel, Sarah; Michels, Nathalie; De Vriendt, Tineke; Patterson, Emma; Cuenca-García, Magdalena; Diethelm, Katharina; Gutin, Bernard; Grammatikaki, Evangelia; Manios, Yannis; Leclercq, Catherine; Ortega, Francisco B; Moreno, Luis A; Gottrand, Frederic; Gonzalez-Gross, Marcela; Widhalm, Kurt; Kafatos, Anthony; Garaulet, Marta; Molnar, Denes; Kaufman, Jean-Marc; Gilbert, Chantal C; Hallström, Lena; Sjöström, Michael; Marcos, Ascensión; De Henauw, Stefaan; Huybrechts, Inge

2013-09-14

Evidence has grown supporting the role for short sleep duration as an independent risk factor for weight gain and obesity. The purpose of the present study was to examine the relationship between sleep duration and dietary quality in European adolescents. The sample consisted of 1522 adolescents (aged 12.5-17.5 years) participating in the European multi-centre cross-sectional ‘Healthy Lifestyle in Europe by Nutrition in Adolescence’ study. Sleep duration was estimated by a self-reported questionnaire. Dietary intake was assessed by two 24 h recalls. The Diet Quality Index for Adolescents with Meal index (DQI-AM) was used to calculate overall dietary quality, considering the components dietary equilibrium, dietary diversity, dietary quality and a meal index. An average sleep duration of ≥ 9 h was classified as optimal, between 8 and 9 h as borderline insufficient and < 8 h as insufficient. Sleep duration and the DQI-AM score were positively associated (β = 0.027, r 0.130, P< 0.001). Adolescents with insufficient (62.05 (sd 14.18)) and borderline insufficient sleep (64.25 (sd 12.87)) scored lower on the DQI-AM than adolescents with an optimal sleep duration (64.57 (sd 12.39)) (P< 0.001; P= 0.018). The present study demonstrated in European adolescents that short sleep duration was associated with a lower dietary quality. This supports the hypothesis that the health consequences of insufficient sleep may be mediated by the relationship of insufficient sleep to poor dietary quality.

Effects of insufficient sleep on circadian rhythmicity and expression amplitude of the human blood transcriptome.

PubMed

Möller-Levet, Carla S; Archer, Simon N; Bucca, Giselda; Laing, Emma E; Slak, Ana; Kabiljo, Renata; Lo, June C Y; Santhi, Nayantara; von Schantz, Malcolm; Smith, Colin P; Dijk, Derk-Jan

2013-03-19

Insufficient sleep and circadian rhythm disruption are associated with negative health outcomes, including obesity, cardiovascular disease, and cognitive impairment, but the mechanisms involved remain largely unexplored. Twenty-six participants were exposed to 1 wk of insufficient sleep (sleep-restriction condition 5.70 h, SEM = 0.03 sleep per 24 h) and 1 wk of sufficient sleep (control condition 8.50 h sleep, SEM = 0.11). Immediately following each condition, 10 whole-blood RNA samples were collected from each participant, while controlling for the effects of light, activity, and food, during a period of total sleep deprivation. Transcriptome analysis revealed that 711 genes were up- or down-regulated by insufficient sleep. Insufficient sleep also reduced the number of genes with a circadian expression profile from 1,855 to 1,481, reduced the circadian amplitude of these genes, and led to an increase in the number of genes that responded to subsequent total sleep deprivation from 122 to 856. Genes affected by insufficient sleep were associated with circadian rhythms (PER1, PER2, PER3, CRY2, CLOCK, NR1D1, NR1D2, RORA, DEC1, CSNK1E), sleep homeostasis (IL6, STAT3, KCNV2, CAMK2D), oxidative stress (PRDX2, PRDX5), and metabolism (SLC2A3, SLC2A5, GHRL, ABCA1). Biological processes affected included chromatin modification, gene-expression regulation, macromolecular metabolism, and inflammatory, immune and stress responses. Thus, insufficient sleep affects the human blood transcriptome, disrupts its circadian regulation, and intensifies the effects of acute total sleep deprivation. The identified biological processes may be involved with the negative effects of sleep loss on health, and highlight the interrelatedness of sleep homeostasis, circadian rhythmicity, and metabolism.

Relationship between body mass index and perceived insufficient sleep among U.S. adults: an analysis of 2008 BRFSS data.

PubMed

Wheaton, Anne G; Perry, Geraldine S; Chapman, Daniel P; McKnight-Eily, Lela R; Presley-Cantrell, Letitia R; Croft, Janet B

2011-05-10

Over the past 50 years, the average sleep duration for adults in the United States has decreased while the prevalence of obesity and associated outcomes has increased. The objective of this study was to determine whether perceived insufficient sleep was associated with body mass index (BMI) in a national sample. We analyzed data from the 2008 Behavioral Risk Factor Surveillance System (BRFSS) survey (N=384,541) in which respondents were asked, "During the past 30 days, for about how many days have you felt you did not get enough rest or sleep?" We divided respondents into six BMI categories and used multivariable linear regression and logistic regression analyses to assess the association between BMI categories and days of insufficient sleep after adjusting for sociodemographic variables, smoking, physical activity, and frequent mental distress. Adjusted mean days of insufficient sleep ranged from 7.9 (95% confidence interval [CI]: 7.8, 8.0) days for people of normal weight to 10.5 (95% CI: 10.2, 10.9) days for those in the highest weight category (BMI≥40). Days of perceived insufficient sleep followed a linear trend across BMI categories. The likelihood of reporting ≥14 days of insufficient sleep in the previous 30 days was higher for respondents in the highest weight category than for those who were normal weight (34.9% vs. 25.2%; adjusted odds ratio=1.7 (95% CI: 1.5, 1.8]). Among U.S. adults, days of insufficient rest or sleep strongly correlated with BMI. Sleep sufficiency should be an important consideration in the assessment of the health of overweight and obese people and should be considered by developers of weight-reduction programs.

Bolus Weekly Vitamin D3 Supplementation Impacts Gut and Airway Microbiota in Adults With Cystic Fibrosis: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial.

PubMed

Kanhere, Mansi; He, Jiabei; Chassaing, Benoit; Ziegler, Thomas R; Alvarez, Jessica A; Ivie, Elizabeth A; Hao, Li; Hanfelt, John; Gewirtz, Andrew T; Tangpricha, Vin

2018-02-01

Disruption of gut microbiota may exacerbate severity of cystic fibrosis (CF). Vitamin D deficiency is a common comorbidity in patients with CF that may influence composition of the gut microbiota. Compare microbiota of vitamin D-sufficient and -insufficient CF patients and assess impact of a weekly high-dose vitamin D3 bolus regimen on gut and airway microbiome in adults with CF and vitamin D insufficiency (25-hydroxyvitamin D < 30 ng/mL). Forty-one subjects with CF were classified into two groups: vitamin D insufficient (n = 23) and vitamin D sufficient (n = 18). Subjects with vitamin D insufficiency were randomized to receive 50,000 IU of oral vitamin D3 or placebo weekly for 12 weeks. Sputum and stool samples were obtained pre- and postintervention and 16S ribosomal RNA genes sequenced using Illumina MiSeq technology. Gut microbiota differed significantly based on vitamin D status with Gammaproteobacteria, which contain numerous, potentially pathogenic species enriched in the vitamin D-insufficient group. Principal coordinates analysis showed differential gut microbiota composition within the vitamin D-insufficient patients following 12 weeks treatment with placebo or vitamin D3 (permutation multivariate analysis of variance = 0.024), with Lactococcus significantly enriched in subjects treated with vitamin D3, whereas Veillonella and Erysipelotrichaceae were significantly enriched in patients treated with placebo. This exploratory study suggests that vitamin D insufficiency is associated with alterations in microbiota composition that may promote inflammation and that supplementation with vitamin D has the potential to impact microbiota composition. Additional studies to determine the impact of vitamin D on microbiota benefit clinical outcomes in CF are warranted. Copyright © 2017 Endocrine Society

Vitamin D insufficiency is associated with insulin resistance independently of obesity in primary schoolchildren. The healthy growth study.

PubMed

Moschonis, George; Androutsos, Odysseas; Hulshof, Toine; Dracopoulou, Maria; Chrousos, George P; Manios, Yannis

2018-04-02

To explore the associations of vitamin D status and obesity with insulin resistance (IR) in children. A sample of 2282 schoolchildren (9-13 years old) in Greece was examined. Sociodemographic, anthropometric (weight, height), biochemical (fasting plasma glucose, serum insulin and 25(OH)D), pubertal status and physical activity data were collected, using standard methods. The "Vitamin D Standardization Program" protocol was applied to standardize serum 25(OH)D values. The prevalence of vitamin D insufficiency (serum 25(OH)D < 50 nmol/L) was higher in obese children compared to their over- and normal-weight counterparts (60.5% vs 51.6% and 51%, P = .017). Furthermore, children with IR (both obese and non-obese) had higher prevalence of vitamin D insufficiency compared to non-obese, non-insulin resistant children (66% and 59.2% vs 49.8%, P < .05), possibly indicating that IR is associated with vitamin D insufficiency, independently of obesity. In line with the above, the results from logistic regression analyses controlled for several potential confounders, showed a 1.48 (95% C.I: 1.2-1.84) higher likelihood for vitamin D insufficiency for insulin resistant children compared to the non-insulin resistant ones, while no significant association was observed with obesity. The present study revealed a high prevalence of vitamin D insufficiency among schoolchildren in Greece, particularly among obese and insulin resistant ones. In addition, it highlighted that the significant association of vitamin D insufficiency with IR is possibly independent of obesity. Further clinical trials are needed to confirm this possible independent association but also explore the potential beneficial effect of vitamin D supplementation on IR and possibly on weight management too. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Estimating GFR Among Participants in the Chronic Renal Insufficiency Cohort (CRIC) Study

PubMed Central

Anderson, Amanda Hyre; Yang, Wei; Hsu, Chi-yuan; Joffe, Marshall M.; Leonard, Mary B.; Xie, Dawei; Chen, Jing; Greene, Tom; Jaar, Bernard G.; Kao, Patricia; Kusek, John W.; Landis, J. Richard; Lash, James P.; Townsend, Raymond R.; Weir, Matthew R.; Feldman, Harold I.

2012-01-01

Background Glomerular filtration rate (GFR) is considered the best measure of kidney function, but repeated assessment is not feasible in most research studies. Study Design Cross-sectional study of 1,433 participants from the Chronic Renal Insufficiency Cohort (CRIC) Study (i.e., the GFR subcohort) to derive an internal GFR estimating equation using a split sample approach. Setting & Participants Adults from 7 US metropolitan areas with mild to moderate chronic kidney disease; 48% had diabetes and 37% were black. Index Test CRIC GFR estimating equation Reference Test or Outcome Urinary 125I-iothalamate clearance testing (measured GFR) Other Measurements Laboratory measures including serum creatinine and cystatin C, and anthropometrics Results In the validation dataset, the model that included serum creatinine, serum cystatin C, age, gender, and race was the most parsimonious and similarly predictive of mGFR compared to a model additionally including bioelectrical impedance analysis phase angle, CRIC clinical center, and 24-hour urinary creatinine excretion. Specifically, the root mean square errors for the separate model were 0.207 vs. 0.202, respectively. The performance of the CRIC GFR estimating equation was most accurate among the subgroups of younger participants, men, non-blacks, non-Hispanics, those without diabetes, those with body mass index <30 kg/m2, those with higher 24-hour urine creatinine excretion, those with lower levels of high-sensitivity C-reactive protein, and those with higher mGFR. Limitations Urinary clearance of 125I-iothalamate is an imperfect measure of true GFR; cystatin C is not standardized to certified reference material; lack of external validation; small sample sizes limit analyses of subgroup-specific predictors. Conclusions The CRIC GFR estimating equation predicts measured GFR accurately in the CRIC cohort using serum creatinine and cystatin C, age, gender, and race. Its performance was best among younger and healthier participants. PMID:22658574

Factors influencing nurses' perceptions of occupational safety.

PubMed

Samur, Menevse; Intepeler, Seyda Seren

2017-01-02

To determine nurses' perceptions of occupational safety and their work environment and examine the sociodemographic traits and job characteristics that influence their occupational safety, we studied a sample of 278 nurses. According to the nurses, the quality of their work environment is average, and occupational safety is insufficient. In the subdimensions of the work environment scale, it was determined that the nurses think "labor force and other resources" are insufficient. In the occupational safety subdimensions "occupational illnesses and complaints" and "administrative support and approaches," they considered occupational safety to be insufficient. "Doctor-nurse-colleague relationships," "exposure to violence," and "work unit" (eg, internal medicine, surgical, intensive care) are the main factors that affect occupational safety. This study determined that hospital administrations should develop and immediately implement plans to ameliorate communication and clinical precautions and to reduce exposure to violence.

Financial Regulations and the Diversification of Funding Sources in Higher Education Institutions: Selected European Experiences

ERIC Educational Resources Information Center

Stachowiak-Kudla, Monika; Kudla, Janusz

2017-01-01

The paper addresses the problem of the financial regulations' impact on the share of private financing in higher education institutions (HEIs). The authors postulate the trade-off between the size and stability of public financing and the regulations fostering stability of HEIs' funds. If the public sources are insufficient then the regulations…

Prevalence of vitamin D deficiency and insufficiency among adult asthmatic patients in Karachi.

PubMed

Kamran, Afshan; Alam, Syed Mahboob; Qadir, Farida

2014-11-01

Vitamin D deficiency has assumed pandemic proportions all over the world. It has been documented as a frequent problem in studies of young adults, elderly person and children in other countries, but there is no reliable data on vitamin D status of adult asthmatic patients in Pakistan. To determine the prevalence of vitamin D deficiency and insufficiency in adult asthmatic patients with moderate to severe asthma using a cross-sectional study design in Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi.311 adult asthmatic patients with moderate to severe asthma were recruited from JPMC, tertiary care hospital in Karachi. Questionnaires were administered together demographics, height, weight, nutritional and physical activity assessment. Blood samples for vitamin D measurement were also taken. Results show high prevalence of vitamin D deficiency and insufficiency (88.10%) in adult patients with moderate to severe persistent asthma. Vitamin D deficiency and insufficiency was more frequently observed in female than in male patients.67.66% of the female patients had serum vitamin D level less than 20 ng/ml as compare to 56.1% of the male patients (p=0.01).

Effects of whole body vibration on muscle spasticity for people with central nervous system disorders: a systematic review.

PubMed

Huang, Meizhen; Liao, Lin-Rong; Pang, Marco Yc

2017-01-01

To examine the effects of whole-body vibration on spasticity among people with central nervous system disorders. Electronic searches were conducted using CINAHL, Cochrane Library, MEDLINE, Physiotherapy Evidence Database, PubMed, PsycINFO, SPORTDiscus and Scopus to identify randomized controlled trials that investigated the effect of whole-body vibration on spasticity among people with central nervous system disorders (last search in August 2015). The methodological quality and level of evidence were rated using the PEDro scale and guidelines set by the Oxford Centre for Evidence-Based Medicine. Nine trials with totally 266 subjects (three in cerebral palsy, one in multiple sclerosis, one in spinocerebellar ataxia, and four in stroke) fulfilled all selection criteria. One study was level 1b (PEDro⩾6 and sample size>50) and eight were level 2b (PEDro<6 or sample size ⩽50). All three cerebral palsy trials (level 2b) reported some beneficial effects of whole-body vibration on reducing leg muscle spasticity. Otherwise, the results revealed no consistent benefits on spasticity in other neurological conditions studied. There is little evidence that change in spasticity was related to change in functional performance. The optimal protocol could not be identified. Many reviewed studies were limited by weak methodological and reporting quality. Adverse events were minor and rare. Whole-body vibration may be useful in reducing leg muscle spasticity in cerebral palsy but this needs to be verified by future high quality trials. There is insufficient evidence to support or refute the notion that whole-body vibration can reduce spasticity in stroke, spinocerebellar ataxia or multiple sclerosis.

Empirical Bayes Gaussian likelihood estimation of exposure distributions from pooled samples in human biomonitoring.

PubMed

Li, Xiang; Kuk, Anthony Y C; Xu, Jinfeng

2014-12-10

Human biomonitoring of exposure to environmental chemicals is important. Individual monitoring is not viable because of low individual exposure level or insufficient volume of materials and the prohibitive cost of taking measurements from many subjects. Pooling of samples is an efficient and cost-effective way to collect data. Estimation is, however, complicated as individual values within each pool are not observed but are only known up to their average or weighted average. The distribution of such averages is intractable when the individual measurements are lognormally distributed, which is a common assumption. We propose to replace the intractable distribution of the pool averages by a Gaussian likelihood to obtain parameter estimates. If the pool size is large, this method produces statistically efficient estimates, but regardless of pool size, the method yields consistent estimates as the number of pools increases. An empirical Bayes (EB) Gaussian likelihood approach, as well as its Bayesian analog, is developed to pool information from various demographic groups by using a mixed-effect formulation. We also discuss methods to estimate the underlying mean-variance relationship and to select a good model for the means, which can be incorporated into the proposed EB or Bayes framework. By borrowing strength across groups, the EB estimator is more efficient than the individual group-specific estimator. Simulation results show that the EB Gaussian likelihood estimates outperform a previous method proposed for the National Health and Nutrition Examination Surveys with much smaller bias and better coverage in interval estimation, especially after correction of bias. Copyright © 2014 John Wiley & Sons, Ltd.

Efficacy, effectiveness and cost-effectiveness of acupuncture for allergic rhinitis - An overview about previous and ongoing studies.

PubMed

Witt, C M; Brinkhaus, B

2010-10-28

In general, allergic rhinitis can be divided into seasonal allergic rhinitis (SAR) and perennial allergic rhinitis (PAR). In the following sections a summary of efficacy and effectiveness studies is presented. For this narrative review we selected studies based on the following parameters: publication in English, sample size ≥30 patients, and at least 6 acupuncture sessions. Most studies aimed to evaluate the specific effects of acupuncture treatment. Only one study evaluated effectiveness and cost-effectiveness of additional acupuncture treatment. The studies which compared acupuncture with sham acupuncture always used a penetrating sham control. A medication control group was used in only two studies and one study combined acupuncture and Chinese herbal medicine. This overview shows that the trials on efficacy and on effectiveness of acupuncture are very heterogeneous. Although penetrating sham controls were used predominantly, these also varied from superficial penetration at acupuncture points to superficial insertion at non-acupuncture points. Although there is some evidence that acupuncture as additional treatment is beneficial and relatively cost-effective, there is insufficient evidence for an acupuncture specific effect in SAR. In contrast, there is some evidence that acupuncture might have specific effects in patients with PAR. However, all of the published efficacy studies are small and conclusions should be made with care. Further studies with a larger sample size are urgently needed to draw more rigorous conclusions and the results of the ongoing trials will provide us with further information within the next two years. Copyright © 2010 Elsevier B.V. All rights reserved.

Enhancing Psychosis-Spectrum Nosology Through an International Data Sharing Initiative.

PubMed

Docherty, Anna R; Fonseca-Pedrero, Eduardo; Debbané, Martin; Chan, Raymond C K; Linscott, Richard J; Jonas, Katherine G; Cicero, David C; Green, Melissa J; Simms, Leonard J; Mason, Oliver; Watson, David; Ettinger, Ulrich; Waszczuk, Monika; Rapp, Alexander; Grant, Phillip; Kotov, Roman; DeYoung, Colin G; Ruggero, Camilo J; Eaton, Nicolas R; Krueger, Robert F; Patrick, Christopher; Hopwood, Christopher; O'Neill, F Anthony; Zald, David H; Conway, Christopher C; Adkins, Daniel E; Waldman, Irwin D; van Os, Jim; Sullivan, Patrick F; Anderson, John S; Shabalin, Andrey A; Sponheim, Scott R; Taylor, Stephan F; Grazioplene, Rachel G; Bacanu, Silviu A; Bigdeli, Tim B; Haenschel, Corinna; Malaspina, Dolores; Gooding, Diane C; Nicodemus, Kristin; Schultze-Lutter, Frauke; Barrantes-Vidal, Neus; Mohr, Christine; Carpenter, William T; Cohen, Alex S

2018-05-16

The latent structure of schizotypy and psychosis-spectrum symptoms remains poorly understood. Furthermore, molecular genetic substrates are poorly defined, largely due to the substantial resources required to collect rich phenotypic data across diverse populations. Sample sizes of phenotypic studies are often insufficient for advanced structural equation modeling approaches. In the last 50 years, efforts in both psychiatry and psychological science have moved toward (1) a dimensional model of psychopathology (eg, the current Hierarchical Taxonomy of Psychopathology [HiTOP] initiative), (2) an integration of methods and measures across traits and units of analysis (eg, the RDoC initiative), and (3) powerful, impactful study designs maximizing sample size to detect subtle genomic variation relating to complex traits (the Psychiatric Genomics Consortium [PGC]). These movements are important to the future study of the psychosis spectrum, and to resolving heterogeneity with respect to instrument and population. The International Consortium of Schizotypy Research is composed of over 40 laboratories in 12 countries, and to date, members have compiled a body of schizotypy- and psychosis-related phenotype data from more than 30000 individuals. It has become apparent that compiling data into a protected, relational database and crowdsourcing analytic and data science expertise will result in significant enhancement of current research on the structure and biological substrates of the psychosis spectrum. The authors present a data-sharing infrastructure similar to that of the PGC, and a resource-sharing infrastructure similar to that of HiTOP. This report details the rationale and benefits of the phenotypic data collective and presents an open invitation for participation.

Evaluation of undersized bioretention stormwater control measures for treatment of highway bridge deck runoff.

PubMed

Luell, S K; Hunt, W F; Winston, R J

2011-01-01

Two grassed bioretention cells were constructed in the easement of a bridge deck in Knightdale, North Carolina, USA, in October, 2009. One was intentionally undersized ('small'), while the other was full sized ('large') per current North Carolina standards. The large and small cells captured runoff from the 25- and 8-mm events, respectively. Both bioretention cells employed average fill media depths of 0.65 m and internal water storage (IWS) zones of 0.6 m. Flow-proportional, composite water quality samples were collected and analyzed for nitrogen species, phosphorus species, and TSS. During 13 months of data collection, the large cell's median effluent concentrations and loads were less than those from the small cell. The small cell's TN and TSS load reductions were 84 and 50%, respectively, of those achieved by the large cell, with both cells significantly reducing TN and TSS. TP loads were not significantly reduced by either cell, likely due to low TP concentrations in the highway runoff which may have approached irreducible levels. Outflow pollutant loads from the large and small cell were not significantly different from one another for any of the examined pollutants. The small cell's relative performance provides support for retrofitting undersized systems in urbanized areas where there is insufficient space available for conventional full-sized stormwater treatment systems.

Spinal Manipulative Therapy for Adolescent Idiopathic Scoliosis: A Systematic Review.

PubMed

Théroux, Jean; Stomski, Norman; Losco, Christine Dominique; Khadra, Christelle; Labelle, Hubert; Le May, Sylvie

The purpose of this study was to perform a systematic review of clinical trials of spinal manipulative therapy for adolescent idiopathic scoliosis. Search strategies were developed for PubMed, CINHAL, and CENTRAL databases. Studies were included through June 2016 if they were prospective trials that evaluated spinal manipulative therapy (eg, chiropractic, osteopathic, physical therapy) for adolescent idiopathic scoliosis. Data were extracted and assessed by 2 independent reviewers. Cochrane risk of bias tools were used to assess the quality of the included studies. Data were reported qualitatively because heterogeneity prevented statistical pooling. Four studies satisfied the inclusion criteria and were critically appraised. The findings of the included studies indicated that spinal manipulative therapy might be effective for preventing curve progression or reducing Cobb angle. However, the lack of controls and small sample sizes precluded robust estimation of the interventions' effect sizes. There is currently insufficient evidence to establish whether spinal manipulative therapy may be beneficial for adolescent idiopathic scoliosis. The results of the included studies suggest that spinal manipulative therapy may be a promising treatment, but these studies were all at substantial risk of bias. Further high-quality studies are warranted to conclusively determine if spinal manipulative therapy may be effective in the management of adolescent idiopathic scoliosis. Copyright © 2017. Published by Elsevier Inc.

Determinants of weight changes during the first 96 hours of life in full-term newborns.

PubMed

Fonseca, Maria João; Severo, Milton; Barros, Henrique; Santos, Ana Cristina

2014-06-01

Newborn weight loss (NWL) in the first 3 days of life is around 6 percent of birthweight (BW). We aim to describe the determinants of an excessive and insufficient NWL in the first 96 hours of life. A sample of 1,288 full-term singletons without congenital abnormality belonging to Generation XXI birth cohort was selected. Newborns were recruited in 2005-2006 at all public units providing obstetrical and neonatal care in Porto, Portugal. Information was collected by face-to-face interview and additionally abstracted from clinical records. Anthropometrics were obtained by trained examiners and newborn weight change (NWC) was estimated as (weight-BW)/BW × 100. We categorized NWL as excessive (below 10th percentile of the sample distribution of NWC: ≤-9.4% of BW), normal (between 10th and 90th percentiles: -9.3 to -4.2%) and insufficient (above 90th percentile: ≥ -4.1%). Adjusted odds ratios (OR) and 95 percent confidence intervals (CI) were calculated using multinomial regression models. Excessive NWL was positively associated with maternal age ≥40 years (OR = 3.32, 95%CI 1.19-9.25), maternal education (OR = 1.04, 95% CI 1.00-1.09), cesarean delivery (OR = 2.42, 95% CI 1.12-5.23), and phototherapy-treated jaundice (OR = 1.69, 95% CI 1.00-2.87). Insufficient NWL was positively associated with low BW (OR = 2.68, 95% CI 1.13-6.33), and formula/mixed feeding (OR = 1.74, 95% CI 1.13-2.66). Excessive NWL was positively associated with maternal age and education, cesarean delivery, and phototherapy-treated jaundice. Insufficient NWL reflected child's feeding. As breastfed newborns did not lose weight excessively, but newborns with formula/mixed feeding had insufficient NWL, our study supports that breastfeeding provides excellent nutrition during this period. © 2014 Wiley Periodicals, Inc.

[Correlation of genomic DNA methylation level with unexplained early spontaneous abortion].

PubMed

Chao, Yuan; Weng, Lidong; Zeng, Rong

2014-10-01

To investigate the correlation of genomic DNA methylation level with unexplained early spontaneous abortion and analyze the role of DNMT1, DNMT3A and DNMT3B. Forty-five villus samples from spontaneous abortion cases (with 33 maternal peripheral blood samples) and 44 villus samples from induced abortion (with 34 maternal peripheral blood samples) were examined with high-pressure liquid chromatography (HPLC) to measure the overall methylation level of the genomic DNA. The expressions of DNMT mRNAs were detected using fluorescence quantitative-PCR in the villus samples from 33 induced abortion cases and 30 spontaneous abortion cases. Genomic DNA methylation level was significantly lower in the villus in spontaneous abortion group than in induced abortion group (P<0.01), but similar in the maternal blood samples between the two groups (P>0.05). The mean mRNA expression levels of DNMT1 and DNMT3A in the villus were significantly lower in spontaneous abortion group than in induced abortion group (P<0.05), but DNMT3B expression showed no significant difference between them (P>0.05). Insufficient genomic DNA methylation in the villus does exist in human early spontaneous abortion, and this insufficiency is probably associated with down-regulated expressions of DNMT1 and DNMT3A.

Adrenal Insufficiency and Addison's Disease

MedlinePlus

... tests in a health care provider’s office, a commercial facility, or a hospital. Hormonal Blood and Urine ... at a health care provider’s office or a commercial facility and sending the sample to a lab ...

Cluster lot quality assurance sampling: effect of increasing the number of clusters on classification precision and operational feasibility.

PubMed

Okayasu, Hiromasa; Brown, Alexandra E; Nzioki, Michael M; Gasasira, Alex N; Takane, Marina; Mkanda, Pascal; Wassilak, Steven G F; Sutter, Roland W

2014-11-01

To assess the quality of supplementary immunization activities (SIAs), the Global Polio Eradication Initiative (GPEI) has used cluster lot quality assurance sampling (C-LQAS) methods since 2009. However, since the inception of C-LQAS, questions have been raised about the optimal balance between operational feasibility and precision of classification of lots to identify areas with low SIA quality that require corrective programmatic action. To determine if an increased precision in classification would result in differential programmatic decision making, we conducted a pilot evaluation in 4 local government areas (LGAs) in Nigeria with an expanded LQAS sample size of 16 clusters (instead of the standard 6 clusters) of 10 subjects each. The results showed greater heterogeneity between clusters than the assumed standard deviation of 10%, ranging from 12% to 23%. Comparing the distribution of 4-outcome classifications obtained from all possible combinations of 6-cluster subsamples to the observed classification of the 16-cluster sample, we obtained an exact match in classification in 56% to 85% of instances. We concluded that the 6-cluster C-LQAS provides acceptable classification precision for programmatic action. Considering the greater resources required to implement an expanded C-LQAS, the improvement in precision was deemed insufficient to warrant the effort. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Prevalence of ciguatoxins in lionfish (Pterois spp.) from Guadeloupe, Saint Martin, and Saint Barthélmy Islands (Caribbean).

PubMed

Soliño, Lucía; Widgy, Saha; Pautonnier, Anthony; Turquet, Jean; Loeffler, Christopher R; Flores Quintana, Harold A; Diogène, Jorge

2015-08-01

Lionfish (Pterois spp.) are invasive species that have recently spread throughout the Caribbean. Lionfish are available for purchase in local markets for human consumption in several islands of the region. We examined the prevalence of ciguatoxins (CTXs) in lionfish from the French Antilles, a ciguatera-endemic region. The neuroblastoma-2a (N2a) cell assay was used to assess composite cytotoxicity in 120 fish samples collected from the surrounding waters of Guadeloupe (n = 60), Saint Barthélemy Islands (n = 55) and Saint Martin (n = 5). Twenty-seven of these samples exhibited CTX-like activity by the N2a assay. Ciguatoxin (CTX) was confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in multiple samples that presented highest composite toxicity levels by N2a. Those fish found to contain CTXs were all from Saint Barthélemy. Lionfish from Guadeloupe and Saint Martin did not exhibit toxin activity, although the sample size from Saint Martin was insufficient to draw any conclusions as to the incidence of CTXs. In this study, we provide information about the potential hazard of ciguatera associated with the consumption of lionfish from known endemic areas. We also demonstrate the utility of the cell-based assay combined with LC-MS/MS to assess activity and to provide structural confirmation of CTXs respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Household demographics and perceived insufficient sleep among US adults.

PubMed

Chapman, Daniel P; Wheaton, Anne G; Perry, Geraldine S; Sturgis, Stephanie L; Strine, Tara W; Croft, Janet B

2012-04-01

It has become increasingly recognized that insufficient sleep is associated with adverse health outcomes. Studies have observed that sleep duration and daytime sleepiness varies by sex and marital status. Few studies have examined the impact of the number of children on sleep. To evaluate the association of marital status and number of children with insufficient sleep and in a large national sample. We analyzed data from the 2008 Behavioral Risk Factor Surveillance System (BRFSS) survey, a population-based telephone survey of non-institutionalized US adults (N = 395,407), in which respondents were asked, "During the past 30 days, for about how many days have you felt you did not get enough rest or sleep?" We used sex-specific, multivariate logistic regression analyses to assess the associations of marital status (married, previously married, never married) and the number of children in the household with frequent insufficient sleep (≥14 days in past 30 days) after adjusting for age, race/ethnicity, and education. In this study population, 23% were never married, 60% were married, and 17% were previously married. Forty-three percent reported having children aged <18 years in the household. Married men (24.3%) were less likely to report frequent insufficient sleep than never married men (28.0%) or previously married men (28.8%). Never married women (33.4%) were more likely to report frequent insufficient sleep than currently married (29.0%) or previously married women (29.0%). The likelihood of frequent insufficient sleep increased in a linear fashion with the number of children in the household for all subgroups (P < 0.05) except among never married men. These findings suggest that the presence of children in the household often increases the frequency of insufficient rest or sleep among the adults with whom they reside. Thus, health care providers may wish to consider the presence of children under 18 years of age a potential "risk factor" for insufficient sleep when counseling adults in the household about the importance of sleep to overall health.

Birth order and selected work-related personality variables.

PubMed

Phillips, A S; Bedeian, A G; Mossholder, K W; Touliatos, J

1988-12-01

A possible link between birth order and various individual characteristics (e. g., intelligence, potential eminence, need for achievement, sociability) has been suggested by personality theorists such as Adler for over a century. The present study examines whether birth order is associated with selected personality variables that may be related to various work outcomes. 3 of 7 hypotheses were supported and the effect sizes for these were small. Firstborns scored significantly higher than later borns on measures of dominance, good impression, and achievement via conformity. No differences between firstborns and later borns were found in managerial potential, work orientation, achievement via independence, and sociability. The study's sample consisted of 835 public, government, and industrial accountants responding to a national US survey of accounting professionals. The nature of the sample may have been partially responsible for the results obtained. Its homogeneity may have caused any birth order effects to wash out. It can be argued that successful membership in the accountancy profession requires internalization of a set of prescribed rules and standards. It may be that accountants as a group are locked in to a behavioral framework. Any differentiation would result from spurious interpersonal differences, not from predictable birth-order related characteristics. A final interpretation is that birth order effects are nonexistent or statistical artifacts. Given the present data and particularistic sample, however, the authors have insufficient information from which to draw such a conclusion.

Label-free photoacoustic nanoscopy

PubMed Central

Danielli, Amos; Maslov, Konstantin; Garcia-Uribe, Alejandro; Winkler, Amy M.; Li, Chiye; Wang, Lidai; Chen, Yun; Dorn, Gerald W.; Wang, Lihong V.

2014-01-01

Abstract. Super-resolution microscopy techniques—capable of overcoming the diffraction limit of light—have opened new opportunities to explore subcellular structures and dynamics not resolvable in conventional far-field microscopy. However, relying on staining with exogenous fluorescent markers, these techniques can sometimes introduce undesired artifacts to the image, mainly due to large tagging agent sizes and insufficient or variable labeling densities. By contrast, the use of endogenous pigments allows imaging of the intrinsic structures of biological samples with unaltered molecular constituents. Here, we report label-free photoacoustic (PA) nanoscopy, which is exquisitely sensitive to optical absorption, with an 88 nm resolution. At each scanning position, multiple PA signals are successively excited with increasing laser pulse energy. Because of optical saturation or nonlinear thermal expansion, the PA amplitude depends on the nonlinear incident optical fluence. The high-order dependence, quantified by polynomial fitting, provides super-resolution imaging with optical sectioning. PA nanoscopy is capable of super-resolution imaging of either fluorescent or nonfluorescent molecules. PMID:25104412

Self-Management Interventions in Stages 1-4 Chronic Kidney Disease: An Integrative Review

PubMed Central

Johnson, Michelle; Zimmerman, Lani; Russell, Cynthia L.; Perkins, Susan M.; Decker, Brian S.

2014-01-01

The prevalence, effect on health outcomes, and economic impact of chronic kidney disease (CKD) have created interest in self-management interventions to help slow disease progression to kidney failure. Seven studies were reviewed to identify knowledge gaps and future directions for research. All studies were published between 2010 and 2013; no investigations were conducted in the United States. Knowledge gaps included the focus on medical self-management tasks with no attention to role or emotional tasks, lack of family involvement during intervention delivery, and an inability to form conclusions about the efficacy of interventions because methodological rigor was insufficient. Educational content varied across studies. Strategies to improve self-management skills and enhance self-efficacy varied and were limited in scope. Further development and testing of theory-based interventions are warranted. There is a critical need for future research using well-designed trials with appropriately powered sample sizes, well-tested instruments, and clear and consistent reporting of results. PMID:25239136

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.

Acquisition of Malay word recognition skills: lessons from low-progress early readers.

PubMed

Lee, Lay Wah; Wheldall, Kevin

2011-02-01

Malay is a consistent alphabetic orthography with complex syllable structures. The focus of this research was to investigate word recognition performance in order to inform reading interventions for low-progress early readers. Forty-six Grade 1 students were sampled and 11 were identified as low-progress readers. The results indicated that both syllable awareness and phoneme blending were significant predictors of word recognition, suggesting that both syllable and phonemic grain-sizes are important in Malay word recognition. Item analysis revealed a hierarchical pattern of difficulty based on the syllable and the phonic structure of the words. Error analysis identified the sources of errors to be errors due to inefficient syllable segmentation, oversimplification of syllables, insufficient grapheme-phoneme knowledge and inefficient phonemic code assembly. Evidence also suggests that direct instruction in syllable segmentation, phonemic awareness and grapheme-phoneme correspondence is necessary for low-progress readers to acquire word recognition skills. Finally, a logical sequence to teach grapheme-phoneme decoding in Malay is suggested. Copyright © 2010 John Wiley & Sons, Ltd.

Correlates and Racial/Ethnic Differences in Bareback Sex Among Men Who Have Sex with Men with Unknown or Negative HIV Serostatus.

PubMed

Vosvick, Mark; Fritz, Sarah; Henry, Doug; Prybutok, Victor; Sheu, Shane; Poe, Jonathon

2016-12-01

Men who have sex with men (MSM), particularly racial/ethnic minority MSM, are disproportionately affected by HIV in the United States and Texas. Bareback sex or condomless anal intercourse (CAI) can be a high HIV risk behavior. Despite this, a majority of MSM continues to engage in barebacking. Research suggests racial/ethnic differences in barebacking exist; however, these conclusions remain unclear due to insufficient sample sizes to compare racial/ethnic groups. Our cross-sectional correlational design explores barebacking correlates (substance use during sex, safe sex fatigue, and optimistic HIV treatment beliefs) within and between racial/ethnic groups among 366 MSM. Regression models are significant for Latino and African-American MSM alone and for all MSM combined, though not significant for European-American and Other Race/Ethnicity MSM alone. Our findings suggest motivations and behaviors underlying barebacking among MSM vary by racial/ethnic membership with clinical implications for informing culturally sensitive HIV interventions and prevention programs for target racial/ethnic groups.

Experimental panic provocation in healthy man—a translational role in anti-panic drug development?

PubMed Central

Kellner, Michael

2011-01-01

Experimental neurochemical provocation of panic attacks in susceptible human subjects has considerably expanded our knowledge of the pathophysiology and psychopharmacology of panic disorder. Some panicogens also elicit short-lived panic-like states in healthy man. This offers the opportunity to assess the anti-panic action of drugs in proof-of-concept studies. However, from current data it is still unclear whether experimental panic in healthy man is a valid translational model. Most such studies in healthy volunteers have been performed using a cholecystokinin tetrapeptide (CCK-4) challenge. While CCK-4 panic was blocked by alprazolam pretreatment, escitalopram showed negative results in healthy man. Preliminary findings on novel investigational drugs and a few problematic results will be reviewed. Small sample sizes in many panic provocation studies, lack of dose-response aspects, and still-insufficient knowledge about the biological underpinning of experimental and spontaneous panic limit the interpretation of existing findings and should inspire further research. PMID:22275853

Self-management interventions in stages 1 to 4 chronic kidney disease: an integrative review.

PubMed

Welch, Janet L; Johnson, Michelle; Zimmerman, Lani; Russell, Cynthia L; Perkins, Susan M; Decker, Brian S

2015-05-01

The prevalence, effect on health outcomes, and economic impact of chronic kidney disease (CKD) have created interest in self-management interventions to help slow disease progression to kidney failure. Seven studies were reviewed to identify knowledge gaps and future directions for research. All studies were published between 2010 and 2013; no investigations were conducted in the United States. Knowledge gaps included the focus on medical self-management tasks with no attention to role or emotional tasks, lack of family involvement during intervention delivery, and an inability to form conclusions about the efficacy of interventions because methodological rigor was insufficient. Educational content varied across studies. Strategies to improve self-management skills and enhance self-efficacy varied and were limited in scope. Further development and testing of theory-based interventions are warranted. There is a critical need for future research using well-designed trials with appropriately powered sample sizes, well-tested instruments, and clear and consistent reporting of results. © The Author(s) 2014.

A scale self-adapting segmentation approach and knowledge transfer for automatically updating land use/cover change databases using high spatial resolution images

NASA Astrophysics Data System (ADS)

Wang, Zhihua; Yang, Xiaomei; Lu, Chen; Yang, Fengshuo

2018-07-01

Automatic updating of land use/cover change (LUCC) databases using high spatial resolution images (HSRI) is important for environmental monitoring and policy making, especially for coastal areas that connect the land and coast and that tend to change frequently. Many object-based change detection methods are proposed, especially those combining historical LUCC with HSRI. However, the scale parameter(s) segmenting the serial temporal images, which directly determines the average object size, is hard to choose without experts' intervention. And the samples transferred from historical LUCC also need experts' intervention to avoid insufficient or wrong samples. With respect to the scale parameter(s) choosing, a Scale Self-Adapting Segmentation (SSAS) approach based on the exponential sampling of a scale parameter and location of the local maximum of a weighted local variance was proposed to determine the scale selection problem when segmenting images constrained by LUCC for detecting changes. With respect to the samples transferring, Knowledge Transfer (KT), a classifier trained on historical images with LUCC and applied in the classification of updated images, was also proposed. Comparison experiments were conducted in a coastal area of Zhujiang, China, using SPOT 5 images acquired in 2005 and 2010. The results reveal that (1) SSAS can segment images more effectively without intervention of experts. (2) KT can also reach the maximum accuracy of samples transfer without experts' intervention. Strategy SSAS + KT would be a good choice if the temporal historical image and LUCC match, and the historical image and updated image are obtained from the same resource.

What Are the Treatments for Primary Ovarian Insufficiency (POI)?

MedlinePlus

... NICHD Contacts for Funding Information Peer Review Small Business Programs About the Programs NICHD Priorities Funding Opportunities ... Opportunities Grants Process, Policies & Strategies Peer Review Small Business Programs Training & Career Development For Applicants Sample Applications ...

A classification of components of workplace disability management programs: results from a systematic review.

PubMed

Gensby, U; Labriola, M; Irvin, E; Amick, B C; Lund, T

2014-06-01

This paper presents results from a Campbell systematic review on the nature and effectiveness of workplace disability management programs (WPDM) promoting return to work (RTW), as implemented and practiced by employers. A classification of WPDM program components, based on the review results, is proposed. Twelve databases were searched between 1948 to July 2010 for peer-reviewed studies of WPDM programs provided by employers to re-entering workers with occupational or non-occupational illnesses or injuries. Screening of articles, risk of bias assessment and data extraction were conducted in pairs of reviewers. Studies were clustered around various dimensions of the design and context of programs. 16,932 records were identified by the initial search. 599 papers were assessed for relevance. Thirteen studies met inclusion criteria. Twelve peer reviewed articles (two non-randomized studies, and ten single group experimental before and after studies), including ten different WPDM programs informed the synthesis of results. Narrative descriptions of the included program characteristics provided insight on program scope, components, procedures and human resources involved. However, there were insufficient data on the characteristics of the sample and the effect sizes were uncertain. A taxonomy classifying policies and practices around WPDM programs is proposed. There is insufficient evidence to draw conclusions on the effectiveness of employer provided WPDM programs promoting RTW. It was not possible to determine if specific program components or specific sets of components are driving effectiveness. The proposed taxonomy may guide future WPDM program evaluation and clarify the setup of programs offered to identify gaps in existing company strategies.

A systematic review of the utility of antidepressant pharmacotherapy in the treatment of vulvodynia pain.

PubMed

Leo, Raphael J; Dewani, Seema

2013-10-01

  Antidepressants have often been recommended as a potential treatment for the management of vulvodynia. However, review of the evidence supporting this recommendation has not been systematically assessed.   To evaluate the efficacy of antidepressant pharmacotherapy in the treatment of vulvodynia.   An assessment of the methodological quality of published reports addressing the utility of antidepressants in the treatment of vulvodynia was undertaken. Several secondary outcomes generated in the existing literature were also examined.   A comprehensive search of the available literature was conducted.   The search yielded 13 published reports, i.e., 2 randomized controlled trials, 1 quasi-experimental trial, 7 non-experimental studies, and 3 case reports. A number of methodological shortcomings were identified in several of the reports with respect to study design including lack of clear inclusion/exclusion criteria, small sample sizes, lack of comparison groups, insufficient blinding, among others. The vast majority of studies utilized tricyclic antidepressants (TCAs). Evidence supporting the benefits of TCAs studied to date was limited, i.e., based largely upon descriptive reports but unsubstantiated by randomized controlled trials. There were no systematic investigations into the comparative efficacy of different antidepressant classes in the treatment of vulvodynia.   There is insufficient evidence to support the recommendation of antidepressant pharmacotherapy in the treatment of vulvodynia. Although some vulvodynia-afflicted patients derive symptom relief from antidepressants, additional research is required to identify those characteristics that would predict those patients for whom antidepressants are more likely to be effective. © 2012 International Society for Sexual Medicine.

Insufficient quality of sputum submitted for tuberculosis diagnosis and associated factors, in Klaten district, Indonesia

PubMed Central

Sakundarno, Mateus; Nurjazuli, Nurjazuli; Jati, Sutopo Patria; Sariningdyah, Retna; Purwadi, Sumarsono; Alisjahbana, Bachti; van der Werf, Marieke J

2009-01-01

Background Sputum smear microscopy is the standard diagnostic method for detection of smear positive pulmonary tuberculosis (TB). Insufficient quality of sputum might result in missing cases. In this study we aimed at assessing the quality of sputum in a district in Central Java and determining patient and health worker factors associated with submission of three good quality sputum samples. Methods In 16 health centers information was collected on the quality of sputum submitted by TB suspects, i.e. volume, color, and viscosity. TB suspects were interviewed to assess their knowledge of TB, motivation to provide sputum and whether they were informed why and how to produce a sputum sample. Health workers were interviewed to assess what information they provided to TB suspects about the reason for sputum examination, methods to produce sputum and characteristics of a good quality sputum sample. All health worker and patient factors were evaluated for association with sputum quality. Results Of 387 TB suspects, 294 (76.0%) could be traced and interviewed, and of 272 (70.3%) information about sputum quality was available. Of those 203 (74.6%) submitted three samples, 90 (33.1%) provided at least one good sample, and 37 (13.6%) provided three good quality sputum samples. Of the 272 TB suspects, 168 (61.8%) mentioned that information on the reason for sputum examination was provided, 66 (24.3%) remembered that they were informed about how to produce sputum and 40 (14.7%) recalled being informed about the characteristics of good quality sputum. Paramedics reported to provide often/always information on the importance of sputum examination, and when to produce sputum. Information on how to produce sputum and characteristics of a good sputum sample was less often provided. None of the studied patient characteristics or health worker factors was associated with providing good quality sputum. Conclusion A considerable number of TB suspects did not provide three sputum samples and a large number of sputum samples were of insufficient quality. Training of health workers in providing health education to the TB suspect about the reason for sputum examination and how to produce a good quality sputum sample should be a priority of the TB program. PMID:19426477

Effect Size for Token Economy Use in Contemporary Classroom Settings: A Meta-Analysis of Single-Case Research

ERIC Educational Resources Information Center

Soares, Denise A.; Harrison, Judith R.; Vannest, Kimberly J.; McClelland, Susan S.

2016-01-01

Recent meta-analyses of the effectiveness of token economies (TEs) report insufficient quality in the research or mixed effects in the results. This study examines the contemporary (post-Public Law 94-142) peer-reviewed published single-case research evaluating the effectiveness of TEs. The results are stratified across quality of demonstrated…

Prevalence of any size adenomas and advanced adenomas in 40- to 49-year-old individuals undergoing screening colonoscopy because of a family history of colorectal carcinoma in a first-degree relative.

PubMed

Gupta, Akshay K; Samadder, Jewel; Elliott, Eric; Sethi, Saurabh; Schoenfeld, Philip

2011-07-01

Per current guidelines, patients with a first-degree relative (FDR) with colorectal cancer (CRC) should get screened at least at age 40. Data about the prevalence of adenomas and advanced adenomas (AAs) in these patients are lacking. To examine the prevalence of adenomas and AAs in 40- to 49-year-old individuals undergoing screening colonoscopy for family history of CRC. Retrospective chart review. Asymptomatic patients 40 to 49 years of age undergoing their first screening colonoscopy at the University of Michigan during the period 1999 to 2009 because of an FDR with CRC. Prevalence of adenomas (any size), AAs, and risk factors associated with adenomas. Among 640 study patients, the prevalence of adenomas (any size) was 15.4% and 3.3% for AAs. Adenoma prevalence was lower if the FDR with CRC was younger than 60 years of age versus an FDR with CRC older than 60 years of age (12.4% vs 19%, P = .034). Male sex (odds ratio 2.6; 95% CI, 1.06-4.4) and advancing age (odds ratio 1.16; 95% CI, 1.03-1.31) were associated with adenomas. Limited data on risk factor exposure and insufficient sample size to assess risk factors for AAs. Among 40- to 49-year-old patients undergoing screening colonoscopy because of an FDR with CRC, the prevalence of adenomas and AAs is low. Further research should determine whether these individuals have a higher prevalence of adenomas compared with average-risk individuals. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Convergence Insufficiency, Accommodative Insufficiency, Visual Symptoms, and Astigmatism in Tohono O'odham Students

PubMed Central

Twelker, J. Daniel; Miller, Joseph M.; Campus, Irene

2016-01-01

Purpose. To determine rate of convergence insufficiency (CI) and accommodative insufficiency (AI) and assess the relation between CI, AI, visual symptoms, and astigmatism in school-age children. Methods. 3rd–8th-grade students completed the Convergence Insufficiency Symptom Survey (CISS) and binocular vision testing with correction if prescribed. Students were categorized by astigmatism magnitude (no/low: <1.00 D, moderate: 1.00 D to <3.00 D, and high: ≥3.00 D), presence/absence of clinical signs of CI and AI, and presence of symptoms. Analyses determine rate of clinical CI and AI and symptomatic CI and AI and assessed the relation between CI, AI, visual symptoms, and astigmatism. Results. In the sample of 484 students (11.67 ± 1.81 years of age), rate of symptomatic CI was 6.2% and symptomatic AI 18.2%. AI was more common in students with CI than without CI. Students with AI only (p = 0.02) and with CI and AI (p = 0.001) had higher symptom scores than students with neither CI nor AI. Moderate and high astigmats were not at increased risk for CI or AI. Conclusions. With-the-rule astigmats are not at increased risk for CI or AI. High comorbidity rates of CI and AI and higher symptoms scores with AI suggest that research is needed to determine symptomatology specific to CI. PMID:27525112

Evidence for Masturbation and Prostate Cancer Risk: Do We Have a Verdict?

PubMed

Aboul-Enein, Basil H; Bernstein, Joshua; Ross, Michael W

2016-07-01

Prostate cancer (PCa) is one of the leading causes of cancer death in men and remains one of the most diagnosed malignancies worldwide. Ongoing public health efforts continue to promote protective factors, such as diet, physical activity, and other lifestyle modifications, against PCa development. Masturbation is a nearly universal safe sexual activity that transcends societal boundaries and geography yet continues to be met with stigma and controversy in contemporary society. Although previous studies have examined associations between sexual activity and PCa risk, anecdotal relations have been suggested regarding masturbation practice and PCa risk. To provide a summary of the published literature and examine the contemporary evidence for relations between masturbation practice and PCa risk. A survey of the current literature using seven academic electronic databases was conducted using search terms and key words associated with masturbation practice and PCa risk. The practice of masturbation and its relation to PCa risk. The literature search identified study samples (n = 16) published before October 2015. Sample inclusions varied by study type, sample size, and primary objective. Protective relations (n = 7) between ejaculation through masturbation and PCa risk were reported by 44% of the study sample. Age range emerged as a significant variable in the relation between masturbation and PCa. Findings included relations among masturbation, ejaculation frequency, and age range as individual factors of PCa risk. No universally accepted themes were identified across the study sample. Throughout the sample, there was insufficient agreement in survey design and data reporting. Potential avenues for new research include frequency of ejaculation and age range as covarying factors that could lead to more definitive statements about masturbation practice and PCa risk. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Postoperative Outcomes of Enucleation and Standard Resections in Patients with a Pancreatic Neuroendocrine Tumor.

PubMed

Jilesen, Anneke P J; van Eijck, Casper H J; Busch, Olivier R C; van Gulik, Thomas M; Gouma, Dirk J; van Dijkum, Els J M Nieveen

2016-03-01

Either enucleation or more extended resection is performed to treat patients with pancreatic neuroendocrine tumor (pNET). Aim was to analyze the postoperative complications for each operation separately. Furthermore, independent risk factors for complications and incidence of pancreatic insufficiency were analyzed. Retrospective all resected patients from two academic hospitals in The Netherlands between 1992 and 2013 were included. Postoperative complications were scored by both ISGPS and Clavien-Dindo criteria. Based on tumor location, operations were compared. Independent risk factors for overall complications were identified. During long-term follow-up, pancreatic insufficiency and recurrent disease were analyzed. Tumor enucleation was performed in 60/205 patients (29%), pancreatoduodenectomy in 65/205 (31%), distal pancreatectomy in 72/205 (35%) and central pancreatectomy in 8/205 (4%) patients. Overall complications after tumor enucleation of the pancreatic head and pancreatoduodenectomy were comparable, 24/35 (69%) versus 52/65 (80%). The same was found after tumor enucleation and resection of the pancreatic tail (36 vs.58%). Number of re-interventions and readmissions were comparable between all operations. After pancreatoduodenectomy, 33/65 patients had lymph node metastasis and in patients with tumor size ≤2 cm, 55% had lymph node metastasis. Tumor in the head and BMI ≥25 kg/m(2) were independent risk factors for complications after enucleation. During follow-up, incidence of exocrine and endocrine insufficiency was significant higher after pancreatoduodenectomy (resp. 55 and 19%) compared to the tumor enucleation and distal pancreatectomy (resp. 5 and 7% vs. 8 and 13%). After tumor enucleation 19% developed recurrent disease. Since the complication rate, need for re-interventions and readmissions were comparable for all resections, tumor enucleation may be regarded as high risk. Appropriate operation should be based on tumor size, location, and functional status of the pNET.

Arbuscular mycorrhizal mediation of biomass-density relationship of Medicago sativa L. under two water conditions in a field experiment.

PubMed

Zhang, Qian; Xu, Liming; Tang, Jianjun; Bai, Minge; Chen, Xin

2011-05-01

The biomass-density relationship (whereby the biomass of individual plants decreases as plant density increases) has generally been explained by competition for resources. Arbuscular mycorrhizal fungi (AMF) are able to affect plant interactions by mediating resource utilization, but whether this AMF-mediated interaction will change the biomass-density relationship is unclear. We conducted an experiment to test the hypothesis that AMF will shift the biomass-density relationship by affecting intraspecific competition. Four population densities (10, 100, 1,000, or 10,000 seedlings per square meter) of Medicago sativa L. were planted in field plots. Water application (1,435 or 327.7 mm/year) simulated precipitation in wet areas (sufficient water) and arid areas (insufficient water). The fungicide benomyl was applied to suppress AMF in some plots ("low-AMF" treatment) and not in others ("high-AMF" treatment). The effect of the AMF treatment on the biomass-density relationship depended on water conditions. High AMF enhanced the decrease of individual biomass with increasing density (the biomass-density line had a steeper slope) when water was sufficient but not when water was insufficient. AMF treatment did not affect plant survival rate or population size but did affect absolute competition intensity (ACI). When water was sufficient, ACI was significantly higher in the high-AMF treatment than in the low-AMF treatment, but ACI was unaffected by AMF treatment when water was insufficient. Our results suggest that AMF status did not impact survival rate and population size but did shift the biomass-density relationship via effects on intraspecific competition. This effect of AMF on the biomass-density relationship depended on the availability of water.

Joint learning of labels and distance metric.

PubMed

Liu, Bo; Wang, Meng; Hong, Richang; Zha, Zhengjun; Hua, Xian-Sheng

2010-06-01

Machine learning algorithms frequently suffer from the insufficiency of training data and the usage of inappropriate distance metric. In this paper, we propose a joint learning of labels and distance metric (JLLDM) approach, which is able to simultaneously address the two difficulties. In comparison with the existing semi-supervised learning and distance metric learning methods that focus only on label prediction or distance metric construction, the JLLDM algorithm optimizes the labels of unlabeled samples and a Mahalanobis distance metric in a unified scheme. The advantage of JLLDM is multifold: 1) the problem of training data insufficiency can be tackled; 2) a good distance metric can be constructed with only very few training samples; and 3) no radius parameter is needed since the algorithm automatically determines the scale of the metric. Extensive experiments are conducted to compare the JLLDM approach with different semi-supervised learning and distance metric learning methods, and empirical results demonstrate its effectiveness.

Adequacy of anti-tuberculosis drug prescriptions in Viet Nam.

PubMed

Hoa, N B; Lauritsen, J M; Rieder, H L

2012-03-21

National Tuberculosis Program, Viet Nam, 2008. To determine drug prescription adherence to national guidelines, to examine factors associated with an erroneous dosage of rifampin (RMP) and to evaluate the impact of an insufficient RMP dosage on treatment outcome. A representative sample of 30 treatment units was randomly selected. All patient treatment cards enrolled in these units were obtained, and data were double-entered and validated before calculating the adequacy of the individual drug prescriptions. Of 3412 tuberculosis treatment cards, 3225 (94.5%) had information on treatment regimen and the patient's weight. Treatment was successful in 89.4%. Prescriptions of tablets/vials conforming to recommendations were found for respectively 91.2%, 89.9%, 92.3% and 94.6% of the patients for RMP/isoniazid, pyrazinamide, ethambutol and streptomycin. Patients in the 25-39 kg weight bracket received insufficient dosages. This was almost entirely attributable to patients at the end of the weight bracket. Nevertheless, no significant association was found between treatment failure and death, body weight and insufficient RMP dosage. Adherence to national recommendations was high. RMP was given in insufficient dosage for patients at the end of a weight range bracket, but the under-dosage was small and did not measurably affect treatment outcome.

Effects of life-state on detectability in a demographic study of the terrestrial orchid Cleistes bifaria

USGS Publications Warehouse

Kery, M.; Gregg, K.B.

2003-01-01

1. Most plant demographic studies follow marked individuals in permanent plots. Plots tend to be small, so detectability is assumed to be one for every individual. However, detectability could be affected by factors such as plant traits, time, space, observer, previous detection, biotic interactions, and especially by life-state. 2. We used a double-observer survey and closed population capture-recapture modelling to estimate state-specific detectability of the orchid Cleistes bifaria in a long-term study plot of 41.2 m2. Based on AICc model selection, detectability was different for each life-state and for tagged vs. previously untagged plants. There were no differences in detectability between the two observers. 3. Detectability estimates (SE) for one-leaf vegetative, two-leaf vegetative, and flowering/fruiting states correlated with mean size of these states and were 0.76 (0.05), 0.92 (0.06), and 1 (0.00), respectively, for previously tagged plants, and 0.84 (0.08), 0.75 (0.22), and 0 (0.00), respectively, for previously untagged plants. (We had insufficient data to obtain a satisfactory estimate of previously untagged flowering plants). 4. Our estimates are for a medium-sized plant in a small and intensively surveyed plot. It is possible that detectability is even lower for larger plots and smaller plants or smaller life-states (e.g. seedlings) and that detectabilities < 1 are widespread in plant demographic studies. 5. State-dependent detectabilities are especially worrying since they will lead to a size- or state-biased sample from the study plot. Failure to incorporate detectability into demographic estimation methods introduces a bias into most estimates of population parameters such as fecundity, recruitment, mortality, and transition rates between life-states. We illustrate this by a simple example using a matrix model, where a hypothetical population was stable but, due to imperfect detection, wrongly projected to be declining at a rate of 8% per year. 6. Almost all plant demographic studies are based on models for discrete states. State and size are important predictors both for demographic rates and detectability. We suggest that even in studies based on small plots, state- or size-specific detectability should be estimated at least at some point to avoid biased inference about the dynamics of the population sampled.

Improving the Representation of Snow Crystal Properties with a Single-Moment Mircophysics Scheme

NASA Technical Reports Server (NTRS)

Molthan, Andrew L.; Petersen, Walter A.; Case, Jonathan L.; Demek, Scott R.

2010-01-01

Single-moment microphysics schemes are utilized in an increasing number of applications and are widely available within numerical modeling packages, often executed in near real-time to aid in the issuance of weather forecasts and advisories. In order to simulate cloud microphysical and precipitation processes, a number of assumptions are made within these schemes. Snow crystals are often assumed to be spherical and of uniform density, and their size distribution intercept may be fixed to simplify calculation of the remaining parameters. Recently, the Canadian CloudSat/CALIPSO Validation Project (C3VP) provided aircraft observations of snow crystal size distributions and environmental state variables, sampling widespread snowfall associated with a passing extratropical cyclone on 22 January 2007. Aircraft instrumentation was supplemented by comparable surface estimations and sampling by two radars: the C-band, dual-polarimetric radar in King City, Ontario and the NASA CloudSat 94 GHz Cloud Profiling Radar. As radar systems respond to both hydrometeor mass and size distribution, they provide value when assessing the accuracy of cloud characteristics as simulated by a forecast model. However, simulation of the 94 GHz radar signal requires special attention, as radar backscatter is sensitive to the assumed crystal shape. Observations obtained during the 22 January 2007 event are used to validate assumptions of density and size distribution within the NASA Goddard six-class single-moment microphysics scheme. Two high resolution forecasts are performed on a 9-3-1 km grid, with C3VP-based alternative parameterizations incorporated and examined for improvement. In order to apply the CloudSat 94 GHz radar to model validation, the single scattering characteristics of various crystal types are used and demonstrate that the assumption of Mie spheres is insufficient for representing CloudSat reflectivity derived from winter precipitation. Furthermore, snow density and size distribution characteristics are allowed to vary with height, based upon direct aircraft estimates obtained from C3VP data. These combinations improve the representation of modeled clouds versus their radar-observed counterparts, based on profiles and vertical distributions of reflectivity. These meteorological events are commonplace within the mid-latitude cold season and present a challenge to operational forecasters. This study focuses on one event, likely representative of others during the winter season, and aims to improve the representation of snow for use in future operational forecasts.

Prospective assessment of the influence of pancreatic cancer resection on exocrine pancreatic function.

PubMed

Sikkens, E C M; Cahen, D L; de Wit, J; Looman, C W N; van Eijck, C; Bruno, M J

2014-01-01

Exocrine insufficiency frequently develops in patients with pancreatic cancer owing to tumour ingrowth and pancreatic duct obstruction. Surgery might restore this function by removing the primary disease and restoring duct patency, but it may also have the opposite effect, as a result of resection of functional parenchyma and anatomical changes. This study evaluated the course of pancreatic function, before and after pancreatic resection. This prospective cohort study included patients with tumours in the pancreatic region requiring pancreatic resection in a tertiary referral centre between March 2010 and August 2012. Starting before surgery, exocrine function was determined monthly by measuring faecal elastase 1 levels (normal value over 0.200 µg per g faeces). Endocrine function, steatorrhoea-related symptoms and bodyweight were also evaluated before and after surgery. Subjects were followed from diagnosis until 6 months after surgery, or until death. Twenty-nine patients were included, 12 with pancreatic cancer, 14 with ampullary carcinoma and three with bile duct carcinoma (median tumour size 2.6 cm). Twenty-six patients underwent pancreaticoduodenectomy and three distal pancreatectomy. Thirteen patients had exocrine insufficiency at preoperative diagnosis. After a median follow-up of 6 months, this had increased to 24 patients. Diabetes was present in seven patients at diagnosis, and developed in one additional patient within 1 month after surgery. Most patients with tumours in the pancreatic region requiring pancreatic resection either had exocrine insufficiency at diagnosis or became exocrine-insufficient soon after surgical resection. © 2013 BJS Society Ltd. Published by John Wiley & Sons Ltd.

Feeling of Pleasure to High-Intensity Interval Exercise Is Dependent of the Number of Work Bouts and Physical Activity Status

PubMed Central

Frazão, Danniel Thiago; de Farias Junior, Luiz Fernando; Dantas, Teresa Cristina Batista; Krinski, Kleverton; Elsangedy, Hassan Mohamed; Prestes, Jonato; Hardcastle, Sarah J.; Costa, Eduardo Caldas

2016-01-01

Objectives To examine the affective responses during a single bout of a low-volume HIIE in active and insufficiently active men. Materials and methods Fifty-eight men (aged 25.3 ± 3.6 years) volunteered to participate in this study: i) active (n = 29) and ii) insufficiently active (n = 29). Each subject undertook i) initial screening and physical evaluation, ii) maximal exercise test, and iii) a single bout of a low-volume HIIE. The HIIE protocol consisted of 10 x 60s work bouts at 90% of maximal treadmill velocity (MTV) interspersed with 60s of active recovery at 30% of MTV. Affective responses (Feeling Scale, -5/+5), rating of perceived exertion (Borg’s RPE, 6–20), and heart rate (HR) were recorded during the last 10s of each work bout. A two-factor mixed-model repeated measures ANOVA, independent-samples t test, and chi-squared test were used to data analysis. Results There were similar positive affective responses to the first three work bouts between insufficiently active and active men (p > 0.05). However, insufficiently active group displayed lower affective responses over time (work bout 4 to 10) than the active group (p < 0.01). Also, the insufficiently active group displayed lower values of mean, lowest, and highest affective response, as well as lower values of affective response at the highest RPE than the active group (p < 0.001). There were no differences in the RPE and HR between the groups (p > 0.05). Conclusions Insufficiently active and active men report feelings of pleasure to few work bouts (i.e., 3–4) during low-volume HIIE, while the affective responses become more unpleasant over time for insufficiently active subjects. Investigations on the effects of low-volume HIIE protocols including a fewer number of work bouts on health status and fitness of less active subjects would be interesting, especially in the first training weeks. PMID:27028191

Surveillance for Emerging Diseases with Multiplexed Point-of-Care Diagnostics

DOE PAGES

Deshpande, Alina; McMahon, Benjamin; Daughton, Ashlynn Rae; ...

2016-06-17

Here, we present an analysis of the diagnostic technologies that were used to identify historical outbreaks of ebola virus disease and consider systematic surveillance strategies that may greatly reduce the peak size of future epidemics. We observe that clinical signs and symptoms alone are often insufficient to recognize index cases of diseases of global concern against the considerable background infectious disease burden that is present throughout the developing world. We propose a simple sampling strategy to enrich in especially dangerous pathogens with a low background for molecular diagnostics by targeting blood borne pathogens in the healthiest age groups. With existingmore » multiplexed diagnostic technologies, such a system could be combined with existing public health screening and reference laboratory systems for malaria, dengue, and common bacteremia or be used to develop such an infrastructure in less-developed locations. Because the needs for valid samples and accurate recording of patient attributes are aligned with needs for global biosurveillance, local public health needs, and improving patient care, co-development of these capabilities appears to be quite natural, flexible, and extensible as capabilities, technologies, and needs evolve over time. Furthermore, implementation of multiplexed diagnostic technologies to enhance fundamental clinical lab capacity will increase public health monitoring and biosurveillance as a natural extension.« less

Landsat-derived cropland mask for Tanzania using 2010-2013 time series and decision tree classifier methods

NASA Astrophysics Data System (ADS)

Justice, C. J.

2015-12-01

80% of Tanzania's population is involved in the agriculture sector. Despite this national dependence, agricultural reporting is minimal and monitoring efforts are in their infancy. The cropland mask developed through this study provides the framework for agricultural monitoring through informing analysis of crop conditions, dispersion, and intensity at a national scale. Tanzania is dominated by smallholder agricultural systems with an average field size of less than one hectare (Sarris et al, 2006). At this field scale, previous classifications of agricultural land in Tanzania using MODIS course resolution data are insufficient to inform a working monitoring system. The nation-wide cropland mask in this study was developed using composited Landsat tiles from a 2010-2013 time series. Decision tree classifiers methods were used in the study with representative training areas collected for agriculture and no agriculture using appropriate indices to separate these classes (Hansen et al, 2013). Validation was done using random sample and high resolution satellite images to compare Agriculture and No agriculture samples from the study area. The techniques used in this study were successful and have the potential to be adapted for other countries, allowing targeted monitoring efforts to improve food security, market price, and inform agricultural policy.

Surveillance for Emerging Diseases with Multiplexed Point-of-Care Diagnostics

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

Deshpande, Alina; McMahon, Benjamin; Daughton, Ashlynn Rae

Here, we present an analysis of the diagnostic technologies that were used to identify historical outbreaks of ebola virus disease and consider systematic surveillance strategies that may greatly reduce the peak size of future epidemics. We observe that clinical signs and symptoms alone are often insufficient to recognize index cases of diseases of global concern against the considerable background infectious disease burden that is present throughout the developing world. We propose a simple sampling strategy to enrich in especially dangerous pathogens with a low background for molecular diagnostics by targeting blood borne pathogens in the healthiest age groups. With existingmore » multiplexed diagnostic technologies, such a system could be combined with existing public health screening and reference laboratory systems for malaria, dengue, and common bacteremia or be used to develop such an infrastructure in less-developed locations. Because the needs for valid samples and accurate recording of patient attributes are aligned with needs for global biosurveillance, local public health needs, and improving patient care, co-development of these capabilities appears to be quite natural, flexible, and extensible as capabilities, technologies, and needs evolve over time. Furthermore, implementation of multiplexed diagnostic technologies to enhance fundamental clinical lab capacity will increase public health monitoring and biosurveillance as a natural extension.« less

Replicability and other features of a high-quality science: Toward a balanced and empirical approach.

PubMed

Finkel, Eli J; Eastwick, Paul W; Reis, Harry T

2017-08-01

Finkel, Eastwick, and Reis (2015; FER2015) argued that psychological science is better served by responding to apprehensions about replicability rates with contextualized solutions than with one-size-fits-all solutions. Here, we extend FER2015's analysis to suggest that much of the discussion of best research practices since 2011 has focused on a single feature of high-quality science-replicability-with insufficient sensitivity to the implications of recommended practices for other features, like discovery, internal validity, external validity, construct validity, consequentiality, and cumulativeness. Thus, although recommendations for bolstering replicability have been innovative, compelling, and abundant, it is difficult to evaluate their impact on our science as a whole, especially because many research practices that are beneficial for some features of scientific quality are harmful for others. For example, FER2015 argued that bigger samples are generally better, but also noted that very large samples ("those larger than required for effect sizes to stabilize"; p. 291) could have the downside of commandeering resources that would have been better invested in other studies. In their critique of FER2015, LeBel, Campbell, and Loving (2016) concluded, based on simulated data, that ever-larger samples are better for the efficiency of scientific discovery (i.e., that there are no tradeoffs). As demonstrated here, however, this conclusion holds only when the replicator's resources are considered in isolation. If we widen the assumptions to include the original researcher's resources as well, which is necessary if the goal is to consider resource investment for the field as a whole, the conclusion changes radically-and strongly supports a tradeoff-based analysis. In general, as psychologists seek to strengthen our science, we must complement our much-needed work on increasing replicability with careful attention to the other features of a high-quality science. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

[Coping strategy and its effect on occupational stress among rail freight dispatchers].

PubMed

Gu, Gui-zhen; Yu, Shan-fa; Li, Kui-rong; Jiang, Kai-you

2010-08-01

To analyse the relationship between coping strategy and occupational stress in rail freight dispatchers. 115 rail freight dispatchers were investigated by using group sampling method, investigation contents included coping strategies, occupational stressors, strains and personalities. The proportion of using coping strategy in rail freight dispatchers is lower. The scores of job future ambiguity, type A behavior and work locus of control in workers with insufficient coping strategy were higher than those in workers with sufficient strategy (P < 0.05 or P < 0.01), but the score of organization commitment score in workers with insufficient coping strategy was lower than those in workers with sufficient strategy (P < 0.05), the differences of scores of some occupational stressor, strain and personality variables between workers with insufficient and those with sufficient in social support, job-family balance, job involvement coping factors of coping strategy were remarkable significant (P < 0.05 or P < 0.01), the differences of scores of occupational stressor, strain and personality variables between workers with insufficient and those with sufficient in ask, logic and time management factors of coping strategy weren't significant (P > 0.05). Logistic regression analysis showed that risk of being job dissatisfaction and daily life stress in workers with insufficient social support coping was three or four times than those with sufficient coping (OR = 3.06 or 4.38, respectively), risk of being daily life stress in workers with insufficient job involvement coping was three times than those with sufficient coping (OR = 3.26). The proportion of using coping strategy in rail freight dispatchers is lower. Coping strategy has influence on the individual's perception of occuaptional stressors, strains and personalities.

[Analysis on sleep duration of 6-12 years old school children in school-day in 8 provinces, China].

PubMed

Shi, Wenhui; Zhai, Yi; Li, Weirong; Shen, Chong; Shi, Xiaoming

2015-05-01

To analyze the influencing factors for sleep duration of school children aged 6-12 years in school-day in 8 provinces in China. The cross sectional study was conducted among 20,603 children aged 6-12 years and selected through stratified random cluster sampling in 8 provinces (municipality and autonomous region) with different geographic characteristics and economic development level in China from September to November, 2010 to understand their sleep duration in school-day and related habits. t test and χ2 test were used to compare the sleep duration of the children. Multivariate stepwise logistic regression analysis was conducted to identify the influencing factors. The survey indicated that the daily average sleep duration of the children in school days was 9.11 hours. The proportions of the children with serious insufficient sleep, insufficient sleep and sufficient sleep were 32.82% (7,672/20,603), 39.70% (8,179/20,603) and 27.48% (5,662/20,603), the children's sleep duration declined with age, so did proportion of children with serious insufficient sleep. There were no sex, urban or rural area and household income level specific significant differences in sleep duration among the children surveyed, and there were no sex specific differences in the proportion of children with serious insufficient sleep, insufficient sleep and sufficient sleep, however, these proportions were statistically different between urban area and rural area and among the regions with different economic level. The proportions of children with serious insufficient sleep and sufficient sleep was higher in rural area than in urban area (χ2=59.96, χ2=45.47, P<0.05), while the proportion of children with insufficient sleep was lower in rural area than in urban area. In the economy developed region, the proportion of children with insufficient sleep was lowest, the difference was statistical significant. After adjusting for sex, weight, diet and exercise time, multivariate logistic regression analysis showed that the factors benefiting children to have 10 hours sleep every day included having high protein diet, exercise, high household economic status and living in urban area. The problem of school children having insufficient sleep was serious in China, especially in the rural area.

Spatiotemporal patterns of the fish assemblages downstream of the Gezhouba Dam on the Yangtze River.

PubMed

Tao, Jiangping; Gong, Yutian; Tan, Xichang; Yang, Zhi; Chang, Jianbo

2012-07-01

An explicit demonstration of the changes in fish assemblages is required to reveal the influence of damming on fish species. However, information from which to draw general conclusions regarding changes in fish assemblages is insufficient because of the limitations of available approaches. We used a combination of acoustic surveys, gillnet sampling, and geostatistical simulations to document the spatiotemporal variations in the fish assemblages downstream of the Gezhouba Dam, before and after the third impoundment of Three Gorges Reservoir (TGR). To conduct a hydroacoustic identification of individual species, we matched the size distributions of the fishes captured by gillnet with those of the acoustic surveys. An optimum threshold of target strength of -50 dB re 1 m(2) was defined, and acoustic surveys were purposefully extended to the selected fish assemblages (i.e., endemic Coreius species) that was acquired by the size and species selectivity of the gillnet sampling. The relative proportion of fish species in acoustic surveys was allocated based on the composition (%) of the harvest in the gillnet surveys. Geostatistical simulations were likewise used to generate spatial patterns of fish distribution, and to determine the absolute abundance of the selected fish assemblages. We observed both the species composition and the spatial distribution of the selected fish assemblages changed significantly after implementation of new flow regulation in the TGR, wherein an immediate sharp population decline in the Coreius occurred. Our results strongly suggested that the new flow regulation in the TGR impoundment adversely affected downstream fish species, particularly the endemic Coreius species. To determine the factors responsible for the decline, we associated the variation in the fish assemblage patterns with changes in the environment and determined that substrate erosion resulting from trapping practices in the TGR likely played a key role.

Pedometer-Determined Physical Activity and Its Comparison with the International Physical Activity Questionnaire in a Sample of Belgian Adults

ERIC Educational Resources Information Center

De Cocker, Katrien; Cardon, Greet; De Bourdeaudhuij, Ilse

2007-01-01

Pedometer-determined physical activity (PA) levels in Belgian adults were provided and compared to PA scores reported in the International Physical Activity Questionnaire (IPAQ). The representative sample (N = 1,239) of the Belgian population took on average 9,655 (4,526) steps/day. According to pedometer indices 58.4% were insufficiently active.…

Serum vitamin D and the metabolic syndrome among osteoporotic postmenopausal female patients of a family practice clinic in Jordan.

PubMed

Yasein, Nada; Shroukh, Wejdan; Hijjawi, Razan

2015-01-01

Vitamin D deficiency and insufficiency and the metabolic syndrome are two common health issues worldwide. The association between these two health problems is subject to debate. This study aims to investigate the association between vitamin D deficiency or insufficiency and the metabolic syndrome in a sample of osteoporotic postmenopausal women attending a family practice clinic in Amman-Jordan. This was an observational cross sectional study. It was carried out in the family practice clinic in Jordan University Hospital. The study included all postmenopausal osteoporotic women attending the clinic between June 2011 and May 2012, yielding a total of 326 subjects. The association between metabolic syndrome and serum vitamin D levels was investigated. Waist circumference, body mass index, triglycerides and fasting blood sugar were significantly higher among postmenopausal women with metabolic syndrome, but HDL cholesterol was significantly lower (p<0.05). The prevalence of metabolic syndrome among all study participants was 42.9%. Triglycerides and LDL cholesterol were significantly higher among women deficiency or insufficiency (p<0.05). The prevalence of vitamin D deficiency or insufficiency was 45.7%. Among patients with metabolic syndrome, the prevalence of vitamin D deficiency or insufficiency was 50.7%. Findings of the current study suggest a lack of relationship between serum vitamin D and metabolic syndrome. However, a significant inverse relationship was found between serum vitamin D levels and both serum triglycerides and LDL levels.

Buccinator sandwich pushback: a new technique for treatment of secondary velopharyngeal incompetence.

PubMed

Hill, C; Hayden, C; Riaz, M; Leonard, A G

2004-05-01

A small percentage of patients have inadequate velopharyngeal closure, or secondary velopharyngeal incompetence, following primary palatoplasty. Use of the buccinator musculomucosal flap has been described for primary palate repair with lengthening, but its use in secondary palate lengthening for the correction of insufficient velopharyngeal closure has not been described. This study presents the results of a series of patients who had correction of secondary velopharyngeal incompetence using bilateral buccinator musculomucosal flaps used as a sandwich. In this prospective study between 1995 and 1998, a group of 16 patients with insufficient velopharyngeal closure as determined by speech assessment and videoradiography were selected. Nasopharyngoscopy was carried out in addition in a number of cases. Case selection was a result of these investigations and clinical examination in which the major factor in velopharyngeal insufficiency was determined to be short palatal length. The patients underwent palate lengthening using bilateral buccinator musculomucosal flaps as a sandwich. All patients were assessed 6 months postoperatively. The operative technique, postoperative course, and recorded postoperative complications including partial/total flap necrosis and residual velopharyngeal insufficiency were evaluated. Preoperative and postoperative speech samples were rated by an independent speech therapist. Ninety-three percent (15 of 16) had a significant improvement in velopharyngeal insufficiency, and 14 patients had no hypernasality postoperatively. Both cases of persistent mild hypernasality had had a recognized postoperative complication. The sandwich pushback technique for the correction of persistent velopharyngeal incompetence was successful in achieving good speech results.

Why Do We Miss Rare Targets? Exploring the Boundaries of the Low Prevalence Effect

DTIC Science & Technology

2008-11-24

effect of prevalence ( F (1,8) = 34.2, p G 0.001, partial eta2 = 0.81), but no effect of set size ( F (1,8) G 1 , n.s.) and no interaction ( F (1,8) G 1 , n.s...Figure 2d; for Prevalence, Target Presence, and all interaction terms, F (1,8) G 1 , n.s.; for Set Size, F (1,8) = 1.7, p 9 0.2). What hints can we get... 1 , n.s.), and no interaction ( F (1,14) G 1 , n.s.). There were insufficient errors on target-absent trials for analysis. An analysis by RT quartile

Prediction of insufficient serum vitamin D status in older women: a validated model.

PubMed

Merlijn, T; Swart, K M A; Lips, P; Heymans, M W; Sohl, E; Van Schoor, N M; Netelenbos, C J; Elders, P J M

2018-05-28

We developed an externally validated simple prediction model to predict serum 25(OH)D levels < 30, < 40, < 50 and 60 nmol/L in older women with risk factors for fractures. The benefit of the model reduces when a higher 25(OH)D threshold is chosen. Vitamin D deficiency is associated with increased fracture risk in older persons. General supplementation of all older women with vitamin D could cause medicalization and costs. We developed a clinical model to identify insufficient serum 25-hydroxyvitamin D (25(OH)D) status in older women at risk for fractures. In a sample of 2689 women ≥ 65 years selected from general practices, with at least one risk factor for fractures, a questionnaire was administered and serum 25(OH)D was measured. Multivariable logistic regression models with backward selection were developed to select predictors for insufficient serum 25(OH)D status, using separate thresholds 30, 40, 50 and 60 nmol/L. Internal and external model validations were performed. Predictors in the models were as follows: age, BMI, vitamin D supplementation, multivitamin supplementation, calcium supplementation, daily use of margarine, fatty fish ≥ 2×/week, ≥ 1 hours/day outdoors in summer, season of blood sampling, the use of a walking aid and smoking. The AUC was 0.77 for the model using a 30 nmol/L threshold and decreased in the models with higher thresholds to 0.72 for 60 nmol/L. We demonstrate that the model can help to distinguish patients with or without insufficient serum 25(OH)D levels at thresholds of 30 and 40 nmol/L, but not when a threshold of 50 nmol/L is demanded. This externally validated model can predict the presence of vitamin D insufficiency in women at risk for fractures. The potential clinical benefit of this tool is highly dependent of the chosen 25(OH)D threshold and decreases when a higher threshold is used.

Measuring individual-level needle and syringe coverage among people who inject drugs in Myanmar.

PubMed

O'Keefe, Daniel; Aung, Soe Moe; Pasricha, Naanki; Wun, Thu; Linn, Soe Khaing; Lin, Nay; Aitken, Campbell; Hughes, Chad; Dietze, Paul

2018-05-10

Myanmar has prioritised people who inject drugs (PWID) as a key population for HIV mitigation efforts, with targets for needle and syringe distribution set at a population level. However, individual-level coverage, defined as the percentage of an individual's injecting episodes covered by a sterile syringe, is a more sensitive measure of intervention coverage. We sought to examine individual-level coverage in a sample of PWID in Myanmar. We recruited 512 PWID through urban drop-in-centres in Yangon, Mandalay and Pyin Oo Lwin. Participants were administered a quantitative questionnaire covering five domains: demographics, drug use, treatment and coverage, and injecting risk behaviour. We calculated past fortnight individual-level syringe coverage, estimating levels of sufficient (≥100% of injecting episodes covered by a sterile syringe) and insufficient (<100%) coverage, and examined associations between key variables and insufficient coverage via logistic regression. Our sample was predominately male (97%), employed (76%), and living in stable accommodation (96%), with a median age of 27. All participants reported heroin as the drug most frequently injected, and injected a median of 27 times in the past two weeks. Nineteen per cent of participants had insufficient coverage in the two weeks before interview. Insufficient coverage was positively associated with syringe re-use (AOR: 5.19, 95% CIs: 2.57, 10.48) and acquiring sterile syringes from a location other than a formal drop-in-centre (AOR: 2.04, 95% CIs: 1.08, 3.82). Participants recruited in Mandalay (AOR: 0.30, 95% CIs: 0.11, 0.80) and Pyin Oo Lwin (AOR: 0.39, 95% CIs: 0.18, 0.87) had lower odds of insufficient coverage than those recruited in Yangon. Our study shows coverage in selected areas of Myanmar was comparable with studies in other countries. Our results inform the delivery of harm reduction services for PWID, specifically by encouraging the use of formal drop-in-centres, over other sources of syringe distribution, such as pharmacies. Copyright © 2018 Elsevier B.V. All rights reserved.

Variability of Stimulant Levels in Nine Sports Supplements Over a 9-Month Period.

PubMed

Attipoe, Selasi; Cohen, Pieter A; Eichner, Amy; Deuster, Patricia A

2016-10-01

Many studies have found that some dietary supplement product labels do not accurately reflect the actual ingredients. However, studies have not been performed to determine if ingredients in the same dietary supplement product vary over time. The objective of this study was to assess the consistency of stimulant ingredients in popular sports supplements sold in the United States over a 9-month period. Three samples of nine popular sports supplements were purchased over the 9-month period. The 27 samples were analyzed for caffeine and several other stimulants (including adulterants). The identity and quantity of stimulants were compared with stimulants listed on the label and stimulants found at earlier time points to determine the variability in individual products over the 9-month period. The primary outcome measure was the variability of stimulant amounts in the products examined. Many supplements did not contain the same number and quantity of stimulants at all time points over the 9-month period. Caffeine content varied widely in five of the six caffeinated supplements compared with the initial measurement (-7% to +266%). In addition, the stimulants-synephrine, octopamine, cathine, ephedrine, pseudoephedrine, strychnine, and methylephedrine-occurred in variable amounts in eight of the nine products. The significance of these findings is uncertain: the sample size was insufficient to support statistical analysis. In our sample of nine popular sports supplements, the presence and quantity of stimulants varied over a 9-month period. However, future studies are warranted to determine if the variability found is significant and generalizable to other supplements.

Prevalence of low vitamin D levels in an urban midwestern obstetric practice.

PubMed

Collins-Fulea, Catherine; Klima, Katherine; Wegienka, Ganesa Rebecca

2012-01-01

This study describes the prevalence of low vitamin D levels in pregnancy in a diverse urban population. This was a retrospective chart review of 2839 women who gave birth at a Michigan hospital between January 1, 2008 and December 31, 2009 and had at least 1 vitamin D (25-hydroxyvitamin D [25(OH)D]) measurement during their pregnancies. Race/ethnic group, wearing the hijab, and season of 25(OH)D sample collection were used in the descriptive analysis. Most women (92.5%) in this study had documented insufficient levels of 25(OH)D (defined as < 30 mL), and 71.7% of all women had deficient levels of 25(OH)D (defined as < 20 ng/mL). Subgroups with the highest percentage of women who were vitamin D deficient were: Middle Eastern (91.8%), African American (81.6%), and Asian (74.3%). Overall, women who wore the hijab were more likely to be deficient (89.5% vs 68.7; P < .0001) and insufficient (98.8% vs 91.4%; P < .0001) compared with women who did not wear the hijab. The data demonstrate the high rate of vitamin D deficiency and insufficiency in this white and nonwhite urban population in which samples were collected in both winter and nonwinter months. The percentage of woman who had 25(OH)D levels below 30 ng/mL was significantly higher than that reported in the National Health and Nutrition Examination Survey III (NHANES III) (92.5% compared to 69%), although NHANES did not sample women in northern climates in the winter months. Even using new diagnostic definitions for vitamin D deficiency from the Institute of Medicine, the proportion of women with vitamin D deficiency and insufficiency was 40% and 31.6%, respectively. Clinicians caring for women in northern climates as well as women who are Middle Eastern, African American, and Asian need to be aware of the risk for vitamin D deficiency and the potential health effects for the mother and infant. © 2012 by the American College of Nurse-Midwives.

Data Validation Package April 2016 Groundwater and Surface Water Sampling at the Monticello, Utah, Disposal and Processing Sites August 2016

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

Nguyen, Jason; Smith, Fred

This semiannual event includes sampling groundwater and surface water at the Monticello Disposal and Processing Sites. Sampling and analyses were conducted as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated) and Program Directive MNT-2016-01. Complete sample sets were collected from 42 of 48 planned locations (9 of 9 former mill site wells, 13 of 13 downgradient wells, 7 of 9 downgradient permeable reactive barrier wells, 4 of 7 seeps and wetlands, and 9 of 10 surface water locations). Planned monitoring locations are shown in Attachment 1, Sampling andmore » Analysis Work Order. Locations R6-M3, SW00-01, Seep 1, Seep 2, and Seep 5 were not sampled due to insufficient water availability. A partial sample was collected at location R4-M3 due to insufficient water. All samples from the permeable reactive barrier wells were filtered as specified in the program directive. Duplicate samples were collected from surface water location Sorenson and from monitoring wells 92-07 and RlO-Ml. Water levels were measured at all sampled wells and an additional set of wells. See Attachment2, Trip Report for additional details. The contaminants of concern (COCs) for the Monticello sites are arsenic, manganese, molybdenum, nitrate+ nitrite as nitrogen (nitrate+ nitrite as N), selenium, uranium, and vanadium. Locations with COCs that exceeded remediation goals are listed in Table 1 and Table 2. Time-concentration graphs of the COCs for all groundwater and surface water locations are included in Attachment 3, Data Presentation. An assessment of anomalous data is included in Attachment 4.« less

Radiocarbon Analysis of Individual Amino Acids: Carbon Blank Quantification for a Small-Sample High-Pressure Liquid Chromatography Purification Method.

PubMed

Bour, Amy L; Walker, Brett D; Broek, Taylor A B; McCarthy, Matthew D

2016-04-05

Compound-specific radiocarbon analysis (CSRA) of amino acids (AAs) is of great interest as a proxy for organic nitrogen (N) cycling rates, dating archeological bone collagen, and investigating processes shaping the biogeochemistry of global N reservoirs. However, recoverable quantities of individual compounds from natural samples are often insufficient for radiocarbon ((14)C) analyses (<50 μg C). Constraining procedural carbon (C) blanks and their isotopic contributions is critical for reporting of accurate CSRA measurements. Here, we report the first detailed quantification of C blanks (including sources, magnitudes, and variability) for a high-pressure liquid chromatography (HPLC) method designed to purify individual AAs from natural samples. We used pairs of AA standards with either modern (M) or dead (D) fraction modern (Fm) values to quantify MC and DC blanks within several chromatographic regions. Blanks were determined for both individual and mixed AA standard injections with peak loadings ranging from 10 to 85 μg C. We found 0.8 ± 0.4 μg of MC and 1.0 ± 0.5 μg of DC were introduced by downstream sample preparation (drying, combustion, and graphitization), which accounted for essentially the entire procedural blank for early eluting AAs. For late-eluting AAs, higher eluent organic content and fraction collected volumes contributed to total blanks of 1.5 ± 0.75 μg of MC and 3.0 ± 1.5 μg of DC. Our final measurement uncertainty for 20 μg of C of most AAs was ±0.02 Fm, although sample size requirements are larger for similar uncertainty in late-eluting AAs. These results demonstrate the first CSRA protocol for many protein AAs with uncertainties comparable to the lowest achieved in prior studies.

Alpine Grassland Soil Organic Carbon Stock and Its Uncertainty in the Three Rivers Source Region of the Tibetan Plateau

PubMed Central

Chang, Xiaofeng; Wang, Shiping; Cui, Shujuan; Zhu, Xiaoxue; Luo, Caiyun; Zhang, Zhenhua; Wilkes, Andreas

2014-01-01

Alpine grassland of the Tibetan Plateau is an important component of global soil organic carbon (SOC) stocks, but insufficient field observations and large spatial heterogeneity leads to great uncertainty in their estimation. In the Three Rivers Source Region (TRSR), alpine grasslands account for more than 75% of the total area. However, the regional carbon (C) stock estimate and their uncertainty have seldom been tested. Here we quantified the regional SOC stock and its uncertainty using 298 soil profiles surveyed from 35 sites across the TRSR during 2006–2008. We showed that the upper soil (0–30 cm depth) in alpine grasslands of the TRSR stores 2.03 Pg C, with a 95% confidence interval ranging from 1.25 to 2.81 Pg C. Alpine meadow soils comprised 73% (i.e. 1.48 Pg C) of the regional SOC estimate, but had the greatest uncertainty at 51%. The statistical power to detect a deviation of 10% uncertainty in grassland C stock was less than 0.50. The required sample size to detect this deviation at a power of 90% was about 6–7 times more than the number of sample sites surveyed. Comparison of our observed SOC density with the corresponding values from the dataset of Yang et al. indicates that these two datasets are comparable. The combined dataset did not reduce the uncertainty in the estimate of the regional grassland soil C stock. This result could be mainly explained by the underrepresentation of sampling sites in large areas with poor accessibility. Further research to improve the regional SOC stock estimate should optimize sampling strategy by considering the number of samples and their spatial distribution. PMID:24819054

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.

[Fundamental strategies to address the problem of public health service delivery insufficiency of disease prevention and control system of China].

PubMed

Shao, Jing-jing; Yu, Jing-jin; Yu, Ming-zhu; Duan, Yong; Gong, Xiangguang; Chen, Zheng; Wang, Hua; Shi, Peiwu; Liang, Zhankai; Yang, Feng; Wang, Dunzhi; Yue, Jianning; Luo, Shi; Luo, Li; Wang, Weicheng; Wang, Ying; Sun, Mei; Su, Zhongxin; Ma, Ning; Xie, Hongbin; Hao, Mo

2005-03-01

To develop and demonstrate the strategies to solve the problem of public health service delivery insufficiency of disease prevention and control system of China. 205 literatures in 8 national academic journals concerning health service management have been reviewed. The method of boundary analysis has been employed to conclude the various reform strategies. Based on the causes and mechanism of public health service delivery insufficiency of disease prevention and control system, the logic analysis has been employed to develop fundamental strategies, which has been demonstrated by 154 CDC using intention questionnaires. There are fundamental strategies to which the agreeing rate for sampling CDC was over 95%: to make sure government should afford the financing function of disease prevention and control and secure the feasible investment for centers of disease prevention and control. Meanwhile, the working efficiency of CDC should be improved through strengthening management and reforming government investing manner.

Examining the Test Of Memory Malingering Trial 1 and Word Memory Test Immediate Recognition as screening tools for insufficient effort.

PubMed

Bauer, Lyndsey; O'Bryant, Sid E; Lynch, Julie K; McCaffrey, Robert J; Fisher, Jerid M

2007-09-01

Assessing effort level during neuropsychological evaluations is critical to support the accuracy of cognitive test scores. Many instruments are designed to measure effort, yet they are not routinely administered in neuropsychological assessments. The Test of Memory Malingering (TOMM) and the Word Memory Test (WMT) are commonly administered symptom validity tests with sound psychometric properties. This study examines the use of the TOMM Trial 1 and the WMT Immediate Recognition (IR) trial scores as brief screening tools for insufficient effort through an archival analysis of a combined sample of mild head-injury litigants ( N = 105) who were assessed in forensic private practices. Results show that both demonstrate impressive diagnostic accuracy and calculations of positive and negative predictive power are presented for a range of base rates. These results support the utility of Trial 1 of the TOMM and the WMT IR trial as screening methods for the assessment of insufficient effort in neuropsychological assessments.

Prospective power calculations for the Four Lab study of a multigenerational reproductive/developmental toxicity rodent bioassay using a complex mixture of disinfection by-products in the low-response region.

PubMed

Dingus, Cheryl A; Teuschler, Linda K; Rice, Glenn E; Simmons, Jane Ellen; Narotsky, Michael G

2011-10-01

In complex mixture toxicology, there is growing emphasis on testing environmentally representative doses that improve the relevance of results for health risk assessment, but are typically much lower than those used in traditional toxicology studies. Traditional experimental designs with typical sample sizes may have insufficient statistical power to detect effects caused by environmentally relevant doses. Proper study design, with adequate statistical power, is critical to ensuring that experimental results are useful for environmental health risk assessment. Studies with environmentally realistic complex mixtures have practical constraints on sample concentration factor and sample volume as well as the number of animals that can be accommodated. This article describes methodology for calculation of statistical power for non-independent observations for a multigenerational rodent reproductive/developmental bioassay. The use of the methodology is illustrated using the U.S. EPA's Four Lab study in which rodents were exposed to chlorinated water concentrates containing complex mixtures of drinking water disinfection by-products. Possible experimental designs included two single-block designs and a two-block design. Considering the possible study designs and constraints, a design of two blocks of 100 females with a 40:60 ratio of control:treated animals and a significance level of 0.05 yielded maximum prospective power (~90%) to detect pup weight decreases, while providing the most power to detect increased prenatal loss.

Prospective Power Calculations for the Four Lab Study of A Multigenerational Reproductive/Developmental Toxicity Rodent Bioassay Using A Complex Mixture of Disinfection By-Products in the Low-Response Region

PubMed Central

Dingus, Cheryl A.; Teuschler, Linda K.; Rice, Glenn E.; Simmons, Jane Ellen; Narotsky, Michael G.

2011-01-01

In complex mixture toxicology, there is growing emphasis on testing environmentally representative doses that improve the relevance of results for health risk assessment, but are typically much lower than those used in traditional toxicology studies. Traditional experimental designs with typical sample sizes may have insufficient statistical power to detect effects caused by environmentally relevant doses. Proper study design, with adequate statistical power, is critical to ensuring that experimental results are useful for environmental health risk assessment. Studies with environmentally realistic complex mixtures have practical constraints on sample concentration factor and sample volume as well as the number of animals that can be accommodated. This article describes methodology for calculation of statistical power for non-independent observations for a multigenerational rodent reproductive/developmental bioassay. The use of the methodology is illustrated using the U.S. EPA’s Four Lab study in which rodents were exposed to chlorinated water concentrates containing complex mixtures of drinking water disinfection by-products. Possible experimental designs included two single-block designs and a two-block design. Considering the possible study designs and constraints, a design of two blocks of 100 females with a 40:60 ratio of control:treated animals and a significance level of 0.05 yielded maximum prospective power (~90%) to detect pup weight decreases, while providing the most power to detect increased prenatal loss. PMID:22073030

Membranous lipodystrophy: case report and review of the literature.

PubMed

Akpinar, Fatma; Demir, Ektan; Apa, Duygu Dusmez

2015-01-01

Membranous lipodystrophy is a distinct type of membranocystic fat necrosis. It is associated with many local and systemic diseases, including vascular disorders. The histopathological changes which characterize this phenomenon are variably sized cysts in the fat lobules of the subcutaneous tissue, which are surrounded by eosinophilic membranes projecting into the cystic space. We report a case of secondary membranous lipodystrophy associated with both hypertension and venous insufficiency.

System Engineering Concept Demonstration, System Engineering Needs. Volume 2

DTIC Science & Technology

1992-12-01

changeability, and invisibility. "Software entities are perhaps more complex for their size than any other human construct..." In addition, software is... human actions and interactions that often fail or insufficient in large organizations. Specific needs in this area include the following: " Each...needed to accomplish incremental review and critique of information. * Automi ..-’ metrics support is needed for the measuring ikey quality aspects of

Value Preferences are More Strongly Associated With Social Class Than With Sex or Race. Illinois Studies of the Economically Disadvantaged, Technical Report Number 17.

ERIC Educational Resources Information Center

Malpass, Roy S.; Symonds, John D.

Preferences for 92 values, obtained from a survey of cross-cultural studies of values, were obtained from two separate and geographically distant sets of groups consisting of black and white males and females of lower- and middle-Class status. The middle-class black population was of insufficient size to include, however. Value preferences were…

A comprehensive porcine blood transcriptome

USDA-ARS?s Scientific Manuscript database

Blood sample analyses are extensively used in high throughput assays in biomedicine, as well as animal genetics and physiology research. However, the draft quality of the current pig genome (Sscrofa 10.2) is insufficient for accurate interpretation of many of these assays because of incomplete gene ...

Comparative evaluation of structural and functional changes in pancreas after endoscopic and surgical management of pancreatic necrosis.

PubMed

Rana, Surinder Singh; Bhasin, Deepak Kumar; Rao, Chalapathi; Sharma, Ravi; Gupta, Rajesh

2014-01-01

Patients with acute necrotizing pancreatitis may develop pancreatic insufficiency and this is commonly seen in patients who have undergone surgery for pancreatic necrosis. Owing to the paucity of relative data, we retrospectively evaluated the structural and functional changes in the pancreas after endoscopic and surgical management of pancreatic necrosis. The records of patients who underwent endoscopic transmural drainage of walled off pancreatic necrosis (WOPN) over the last 3 years and who completed at least 6 months of follow up were analyzed. Structural and functional changes in these patients were compared with 25 historical surgical controls (operated in 2005-2006). Twenty six patients (21 M; mean age 35.4±8.1 years) who underwent endoscopic drainage for WOPN were followed up for 22.3±8.6 months. During the follow up, five (19.2%) patients developed diabetes with 3 patients requiring insulin and 1 patient with steatorrhea requiring pancreatic enzyme supplementation. The pancreatic fluid collection (PFC) recurred in 1 patient whose stents spontaneously migrated out. On follow up, in the surgery group, 2 (8%) patients developed steatorrhea and 11 (44%) developed diabetes. Five (20%) of these patients had recurrence of PFC. On comparison of follow up results of endoscopic drainage with surgery, recurrence rates as well as frequency of endocrine and exocrine insufficiency was lower in the endoscopic group but difference was not significant. Structural and functional impairment of pancreas is seen less frequently in patients with pancreatic necrosis treated endoscopically compared to patients undergoing surgery, although the difference was insignificant. Further studies with large sample size are needed to confirm these initial results.

Self-administered foot reflexology for the management of chronic health conditions: a systematic review.

PubMed

Song, Hyun Jin; Choi, Sun Mi; Seo, Hyun-Ju; Lee, Heeyoung; Son, Heejeong; Lee, Sanghun

2015-02-01

To systematically review the effect of self-administered foot reflexology in patients with chronic health conditions. Electronic databases were searched for literature published from 1948 to January 2014. The databases included MEDLINE, EMBASE, the Cochrane Library, CINAHL, CNKI, J-STAGE, Koreamed, Kmbase, KISS, NDSL, KISTI, and OASIS. Key search terms were "exp/relaxation therapy," "foot," "reflexology," "zone therapy," and "self." All study designs were included. Two raters independently extracted data and assessed study quality by using the Cochrane risk of bias tool (for randomized controlled trials) and the risk of bias assessment tool for nonrandomized studies (for nonrandomized and before-and-after studies). A qualitative and descriptive analysis was performed because of the clinical diversity associated with chronic health conditions. Of the 224 records assessed, 4 trials met the inclusion criteria: 3 nonrandomized controlled trials and 1 before-and-after study without comparison. Self-administered foot reflexology might have a positive effect in type 2 diabetes, but the low quality of the included study and the lack of adequately reported clinical outcomes obscure the results. Two studies of hypertensive patients and 1 study of patients with urinary incontinence showed that self-performed foot reflexology may exert a beneficial effect on lowering blood pressure and urinary incontinence; however, given the small sample size and the lack of any description of medications and other cointerventions, there was insufficient evidence to conclusively determine whether foot reflexology had any effect. The included studies on self-administered foot reflexology in patients with type 2 diabetes, hypertension, or urinary incontinence provided insufficient evidence to determine a treatment effect. Therefore, a well-designed, large-scale, and randomized controlled trial is needed to confirm the effect of self-administered foot reflexology for chronic conditions.

Relationships Between Neighbourhood Physical Environmental Attributes and Older Adults' Leisure-Time Physical Activity: A Systematic Review and Meta-Analysis.

PubMed

Van Cauwenberg, Jelle; Nathan, Andrea; Barnett, Anthony; Barnett, David W; Cerin, Ester

2018-05-02

Activity-friendly neighbourhood physical environments with access to recreational facilities are hypothesised to facilitate leisure-time physical activity (LTPA) among older adults (≥ 65 years old). The aim of the current study was to systematically review and quantitatively summarise study findings on the relationships between physical environmental attributes and LTPA among older adults. An extensive search of literature, including grey literature, yielded 72 articles eligible for inclusion. The reported associations between seven categories of environmental attributes and six LTPA outcomes were extracted, weighted by sample size and study quality, and quantitatively summarised. Reported moderating effects of individual and environmental characteristics and neighbourhood definition were also examined. We observed positive associations for walkability (p = 0.01), land-use mix-access (p = 0.02) and aesthetically pleasing scenery (p < 0.001) with leisure-time walking. For leisure-time walking within the neighbourhood, evidence was found for positive associations with land-use mix-access (p = 0.03) and access to public transit (p = 0.05), and a negative association with barriers to walking/cycling (p = 0.03). Evidence for positive relationships between overall LTPA and access to recreational facilities (p = 0.01) and parks/open space (p = 0.04) was found. Several environmental attribute-LTPA outcome combinations were insufficiently studied to draw conclusions. No consistent moderating effects were observed for individual and environmental characteristics and neighbourhood definition. The observed significant relationships can be used to inform policy makers and planners on how to (re-)design neighbourhoods that promote LTPA among older adults. Many environmental attribute-LTPA outcome relationships have been studied insufficiently and several methodological issues remain to be addressed. PROSPERO 2016:CRD42016051180.

Physical activity preferences, preferred sources of assistance, and perceived barriers to increased activity among physically inactive Australians.

PubMed

Booth, M L; Bauman, A; Owen, N; Gore, C J

1997-01-01

Participation in regular moderate or vigorous physical activity substantially reduces risk for all-cause and cardiovascular-disease mortality and confers other health benefits. Efforts to decrease the population prevalence of inactivity will have a greater impact if they are tailored to the needs and preferences of the community. In the Pilot Survey of the Fitness of Australians, a questionnaire was administered to a randomly selected sample of 2,298 adults and included questions on the preferred sources of assistance or support to become physically active, preferred activities, and barriers to regular participation. The responses of those who were identified as insufficiently physically active (n = 1,232; 53.6%) were examined for men and women separately and for those aged 18 to 39, 40 to 59, and 60 to 78 years. The most-preferred activity was walking (38 and 68% of the youngest and oldest age groups, respectively). The most frequently cited barriers to more-regular participation in the youngest age group were insufficient time, lack of motivation and child care responsibilities. Among those aged 60 to 78 years, injury or poor health were the most frequently cited barriers to activity. The most-preferred source of advice or assistance changed with age: more than 50% of the oldest age group wanted advice from a health professional (compared with 22% of the youngest group) and the opportunity to exercise with a group was the most preferred source of support for the youngest age group. The physical activity-related attributes of men and women and of younger and older age groups described in this study may be used to provide more relevant and appealing options for those who might otherwise be missed by "one-size-fits-all" physical activity promotion strategies.

Minimally invasive therapy for gynaecological symptoms related to a niche in the caesarean scar: a systematic review.

PubMed

van der Voet, L F; Vervoort, A J; Veersema, S; BijdeVaate, A J; Brölmann, H A M; Huirne, J A F

2014-01-01

Various therapies are currently used to treat symptoms related to the niche (an anechoic area) in the caesarean scar, in particular to treat abnormal uterine bleeding (AUB). To systematically review the available literature reporting on the effect of various therapies on niche-related symptoms. A systematic search of MEDLINE, Embase, Cochrane, trial registers and congress abstracts from AAGL and ESGE was performed. Articles reporting on the effectiveness of therapies other than hysterectomy in women with niche-related symptoms were included. Studies were included if they reported one of the following outcomes: effect on AUB, pain relief, sexual function, quality of life (QOL), and surgical, anatomic, fertility, or pregnancy outcome. Two authors independently selected the articles to be included. The Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines were followed. A standardised checklist was used to score the methodological quality of the included studies. Twelve studies were included, reporting on hysteroscopic niche resection (eight studies, 384 patients), laparoscopic repair (one study, 13 patients), (laparoscopic assisted) vaginal repair (two studies, 47 patients), and oral contraceptives (OCs) (one study, 11 patients). Reported AUB improved in the vast majority of the patients after these interventions, ranging from 87 to 100%. The rate of complications was low. Pregnancies were reported after therapy; however, sample sizes and follow-up were insufficient to study fertility or pregnancy outcome. The methodological quality of the selected papers was considered to be moderate to poor, and was therefore insufficient to make solid conclusions. More evidence is needed before (surgical) niche interventions are implemented in daily practice. © 2013 Royal College of Obstetricians and Gynaecologists.

Comparison of vision disorders between children in mainstream and special education classes in government primary schools in Malaysia.

PubMed

Abu Bakar, Nurul Farhana; Chen, Ai-Hong; Md Noor, Abdul Rahim; Goh, Pik-Pin

2012-08-01

The visual status of children with learning disabilities has not been extensively studied. This study aimed to compare vision disorders between children in mainstream classes and those with learning disabilities attending special education classes in government primary schools in Malaysia. In this cross-sectional comparative study, 60 school children (30 from mainstream classes and 30 from special education classes) who were matched in age (6-12 years old) and ethnicity (Malay, Chinese and Indian) were examined. The subjects were recruited using non-probability convenience sampling. A complete eye examination was performed to detect three major vision disorders, namely refractive error, lag of accommodation and convergence insufficiency. The overall prevalence of refractive error, lag of accommodation and convergence insufficiency was found to be 65.0%, 43.3% and 35.2%, respectively. Convergence insufficiency (χ² = 24.073, p < 0.001) was found to be associated with children in special education classes. No association was found between refractive error and lag of accommodation (p > 0.05) with the type of classes. Children in special education classes are more likely to have convergence insufficiency compared to children in mainstream classes. Thus, vision screening programmes for children in special education classes may need to be modified.

Bedtime procrastination: introducing a new area of procrastination

PubMed Central

Kroese, Floor M.; De Ridder, Denise T. D.; Evers, Catharine; Adriaanse, Marieke A.

2014-01-01

Background: Procrastination is a prevalent and problematic phenomenon that has mostly been studied in the domain of academic behavior. The current study shows that procrastination may also lead to harmful outcomes in the area of health behavior, introducing bedtime procrastination as an important factor related to getting insufficient sleep and consequently affecting individual well-being. Bedtime procrastination is defined as failing to go to bed at the intended time, while no external circumstances prevent a person from doing so. Methods: To empirically support the conceptual introduction of bedtime procrastination, an online survey study was conducted among a community sample (N = 177). The relationship between bedtime procrastination and individual difference variables related to self-regulation and general procrastination was assessed. Moreover, it was investigated whether bedtime procrastination was a predictor of self-reported sleep outcomes (experienced insufficient sleep, hours of sleep, fatigue during the day). Results: Bedtime procrastination was negatively associated with self-regulation: people who scored lower on self-regulation variables reported more bedtime procrastination. Moreover, self-reported bedtime procrastination was related to general reports of insufficient sleep above and beyond demographics and self-regulation. Conclusions: Introducing a novel domain in which procrastinators experience problems, bedtime procrastination appears to be a prevalent and relevant issue that is associated with getting insufficient sleep. PMID:24994989

Bedtime procrastination: introducing a new area of procrastination.

PubMed

Kroese, Floor M; De Ridder, Denise T D; Evers, Catharine; Adriaanse, Marieke A

2014-01-01

Procrastination is a prevalent and problematic phenomenon that has mostly been studied in the domain of academic behavior. The current study shows that procrastination may also lead to harmful outcomes in the area of health behavior, introducing bedtime procrastination as an important factor related to getting insufficient sleep and consequently affecting individual well-being. Bedtime procrastination is defined as failing to go to bed at the intended time, while no external circumstances prevent a person from doing so. To empirically support the conceptual introduction of bedtime procrastination, an online survey study was conducted among a community sample (N = 177). The relationship between bedtime procrastination and individual difference variables related to self-regulation and general procrastination was assessed. Moreover, it was investigated whether bedtime procrastination was a predictor of self-reported sleep outcomes (experienced insufficient sleep, hours of sleep, fatigue during the day). Bedtime procrastination was negatively associated with self-regulation: people who scored lower on self-regulation variables reported more bedtime procrastination. Moreover, self-reported bedtime procrastination was related to general reports of insufficient sleep above and beyond demographics and self-regulation. Introducing a novel domain in which procrastinators experience problems, bedtime procrastination appears to be a prevalent and relevant issue that is associated with getting insufficient sleep.

Adequacy of anti-tuberculosis drug prescriptions in Viet Nam

PubMed Central

Lauritsen, J. M.; Rieder, H. L.

2012-01-01

Setting: National Tuberculosis Program, Viet Nam, 2008. Objectives: To determine drug prescription adherence to national guidelines, to examine factors associated with an erroneous dosage of rifampin (RMP) and to evaluate the impact of an insufficient RMP dosage on treatment outcome. Methods: A representative sample of 30 treatment units was randomly selected. All patient treatment cards enrolled in these units were obtained, and data were double-entered and validated before calculating the adequacy of the individual drug prescriptions. Results: Of 3412 tuberculosis treatment cards, 3225 (94.5%) had information on treatment regimen and the patient’s weight. Treatment was successful in 89.4%. Prescriptions of tablets/vials conforming to recommendations were found for respectively 91.2%, 89.9%, 92.3% and 94.6% of the patients for RMP/isoniazid, pyrazinamide, ethambutol and streptomycin. Patients in the 25–39 kg weight bracket received insufficient dosages. This was almost entirely attributable to patients at the end of the weight bracket. Nevertheless, no significant association was found between treatment failure and death, body weight and insufficient RMP dosage. Conclusions: Adherence to national recommendations was high. RMP was given in insufficient dosage for patients at the end of a weight range bracket, but the under-dosage was small and did not measurably affect treatment outcome. PMID:26392937

The time is now for a new approach to primary ovarian insufficiency

PubMed Central

Cooper, Amber R.; Baker, Valerie L.; Sterling, Evelina W.; Ryan, Mary E.; Woodruff, Teresa K.; Nelson, Lawrence M.

2010-01-01

Objective To articulate the need for a new approach to primary ovarian insufficiency. The condition, also known as premature menopause or premature ovarian failure, is defined by the presence of menopausal-level serum gonad otropins in association with irregular menses in adolescent girls or women younger than 40 years. It can be iatrogenic as related to cancer therapy or may arise spontaneously, either alone or as part of a host of ultrarare syndromes. In a large percentage of spontaneous cases no pathogenic mechanism can be identified. Design Literature review and consensus building at a multidisciplinary scientific workshop. Conclusion(s) There are major gaps in knowledge regarding the etiologic mechanisms, psychosocial effects, natural history, and medical and psychosocial management of primary ovarian insufficiency. An international research consortium and disease registry formed under the guidance of an umbrella organization would provide a pathway to comprehensively increase basic and clinical knowledge about the condition. Such a consortium and patient registry also would provide clinical samples and clinical data with a goal toward defining the specific pathogenic mechanisms. An international collaborative approach that combines the structure of a patient registry with the principles of integrative care and community-based participatory research is needed to advance the field of primary ovarian insufficiency. PMID:20188353

[Long QT syndrome and polymorphic ventricular tachycardia due to hypopituitarism. Report of one case].

PubMed

García-Castro, José Miguel; García-Martín, Antonia; Guirao-Arrabal, Emilio; Carrillo-Alascio, Pedro Luis

2017-07-01

Symptoms of hypopituitarism are usually chronic and nonspecific, but rarely the disease can have acute and life threatening manifestations. We report a 53 years old female with a pituitary adenoma that was admitted to our hospital because of syncope. The electrocardiogram showed sinus bradycardia with a prolonged QT interval. Frequent runs of non-sustained polymorphic ventricular tachycardia were noted on telemetry. The patient had a history of severe acute headaches in the previous days and laboratory tests revealed severe secondary hypothyroidism, adrenal insufficiency and a decrease in pituitary hormones. A magnetic resonance imaging of the head showed changes in the size and contrast enhancement of the adenoma. A diagnosis of hypopituitarism secondary to pituitary apoplexy was made and treatment with hydrocortisone and, subsequently, levothyroxine was started. Hormonal disorders such as hypothyroidism, adrenal insufficiency or hypopituitarism should be considered as unusual causes for reversible cardiomyopathy, long QT syndrome and ventricular arrhythmias.

Omega-3 Fatty Acid and Nutrient Deficits in Adverse Neurodevelopment and Childhood Behaviors

PubMed Central

Hibbeln, Joseph. R.; Gow, Rachel V.

2014-01-01

Synopsis Nutritional insufficiencies of omega-3 highly unsaturated fatty acids (HUFAs) may have adverse effects on brain development and neurodevelopmental outcomes. A recent meta-analysis of ten randomized controlled trials of omega-3 HUFAs reported a small to modest effect size for the efficacy of omega-3 for treating symptoms of ADHD in youth. Several controlled trials of omega-3 HUFAs combined with micronutrients (vitamins, minerals) show sizeable reductions in aggressive, antisocial, and violent behavior in youth and in young adult prisoners. Meta-analyses report efficacy for depressive symptoms in adults, and preliminary findings suggest anti-suicidal properties in adults, but studies in youth are insufficient to draw any conclusions regarding mood. Dietary adjustments to increase omega-3 and reduce omega-6 HUFA consumption are sensible recommendations for youth and adults based on general health considerations, while the evidence base for omega-3 HUFAs as potential psychiatric treatments develops. PMID:24975625

Outcomes of tubeless percutaneous nephrolithotomy in patients with chronic renal insufficiency.

PubMed

Etemadian, Masoud; Maghsoudi, Robab; Shadpour, Pejman; Ghasemi, Hadi; Shati, Mohsen

2012-05-01

We evaluated the outcomes of percutaneous nephrolithotomy in patients with chronic renal insufficiency. A total of 60 patients with a creatinine level greater than 1.5 mg/dL who underwent PCNL were included. Serum creatinine level, as a kidney function index, was assessed before and after the operation. The mean calculus size was 31.13 ± 9.38 mm. The mean pre-operative and 2-week postoperative serum creatinine levels were 2.43 ± 0.75 mg/dL and 2.08 ± 0.78 mg/dL, respectively. There was a significant difference between the pre-operative and postoperative creatinine levels in all postoperative days (days 1, 2, and 14). Fifty of the 60 patients (83.3%) were stone free. Ten patients (16.6%) developed postoperative fever. We can conclude that percutaneous nephrolithotomy seems to be a safe and effective therapeutic option for kidney calculi in patients with chronic kidney disease.

[Opinion of women from a family health unit about the quantity of mothermilk produced].

PubMed

Borges, Ana Luiza Vilela; Philippi, Sonia Tucunduva

2003-01-01

This is a study aimed at knowing the opinion of women about the quantity of mothermilk produced, since insufficient milk is one of the main reasons mentioned by women from different cultures when introducing complementary feeding in children's diet before the fourth month of life. The interviews were made at the homes of 41 women from a family health unit in the Eastern area of S o Paulo City in 1998 and 1999. The majority of the mothers (82.9%) considered they were producing a sufficient quantity of mothermilk. As evaluation criteria for the produced quantity of mothermilk, they used the size of the breasts, the spontaneous dropping of milk and the mood of the child after breastfeeding. All women introduced artificial milk before the fourth month, but those who mentioned insufficient milk did it earlier (p=0.0088).

Nutritional status of children from Cochabamba, Bolivia: a cross-sectional study.

PubMed

Masuet-Aumatell, Cristina; Ramon-Torrell, Josep Maria; Banqué-Navarro, Marta; Dávalos-Gamboa, María Del Rosario; Montaño-Rodríguez, Sandra Lucía

2015-12-01

To assess the adequacy of energy and nutritional intakes compared to recommended daily intakes (RDIs) in schoolchildren from the Cochabamba region (Bolivia) and to determine micronutrient intake distributions across different ages and genders. This nutritional study (n = 315) was part of a larger population-based crosssectional study (the "Bolkid" survey) that collected data on schoolchildren 5-16 years old in 2010 in the Cochabamba region. Information about food intake was gathered with a semiquan-titative, food-frequency, parent-administered questionnaire about l2 months before the study. Descriptive and bivariate analyses of energy and nutrient intakes were assessed. For all ages studied and both genders, the average energy and micronutrient intakes were acceptable but below the requirements. The diet included high amounts of fiber, some minerals (iron, magnesium, phosphorus, potassium, sodium), and vitamins (pantothenic acid, niacin, vitamins B2, B12, C, and E), but was low in calcium and vitamin D. However, more than half the children had insufficient energy intake, and low calcium, vitamin A, and vitamin D intakes, according to RDIs adjusted for age and gender; one-third of the children had insufficient folate and magnesium intakes; and adolescent girls had low iron intakes. Regardless of recommendations or demographic characteristics, the vast majority of children in Cochabamba consumed insufficient energy and too little calcium, folate, magnesium, and vitamin A and D. In addition, adolescent girls consumed insufficient iron. Higher energy intake for schoolchildren through increased food availability, frequency, and size portions in daily meals should be a priority for Bolivian public health institutions.

Implantation of the Medtronic Harmony Transcatheter Pulmonary Valve Improves Right Ventricular Size and Function in an Ovine Model of Postoperative Chronic Pulmonary Insufficiency.

PubMed

Schoonbeek, Rosanne C; Takebayashi, Satoshi; Aoki, Chikashi; Shimaoka, Toru; Harris, Matthew A; Fu, Gregory L; Kim, Timothy S; Dori, Yoav; McGarvey, Jeremy; Litt, Harold; Bouma, Wobbe; Zsido, Gerald; Glatz, Andrew C; Rome, Jonathan J; Gorman, Robert C; Gorman, Joseph H; Gillespie, Matthew J

2016-10-01

Pulmonary insufficiency is the nexus of late morbidity and mortality after transannular patch repair of tetralogy of Fallot. This study aimed to establish the feasibility of implantation of the novel Medtronic Harmony transcatheter pulmonary valve (hTPV) and to assess its effect on pulmonary insufficiency and ventricular function in an ovine model of chronic postoperative pulmonary insufficiency. Thirteen sheep underwent baseline cardiac magnetic resonance imaging, surgical pulmonary valvectomy, and transannular patch repair. One month after transannular patch repair, the hTPV was implanted, followed by serial magnetic resonance imaging and computed tomography imaging at 1, 5, and 8 month(s). hTPV implantation was successful in 11 animals (85%). There were 2 procedural deaths related to ventricular fibrillation. Seven animals survived the entire follow-up protocol, 5 with functioning hTPV devices. Two animals had occlusion of hTPV with aneurysm of main pulmonary artery. A strong decline in pulmonary regurgitant fraction was observed after hTPV implantation (40.5% versus 8.3%; P=0.011). Right ventricular end diastolic volume increased by 49.4% after transannular patch repair (62.3-93.1 mL/m 2 ; P=0.028) but was reversed to baseline values after hTPV implantation (to 65.1 mL/m 2 at 8 months, P=0.045). Both right ventricular ejection fraction and left ventricular ejection fraction were preserved after hTPV implantation. hTPV implantation is feasible, significantly reduces pulmonary regurgitant fraction, facilitates right ventricular volume improvements, and preserves biventricular function in an ovine model of chronic pulmonary insufficiency. This percutaneous strategy could potentially offer an alternative for standard surgical pulmonary valve replacement in dilated right ventricular outflow tracts, permitting lower risk, nonsurgical pulmonary valve replacement in previously prohibitive anatomies. © 2016 American Heart Association, Inc.

Family Characteristics and Intellectual Growth: An Examination by Race.

ERIC Educational Resources Information Center

Barnes, Jonathan

1979-01-01

The confluence model for explaining the influence of birth order on intelligence was applied to a sample of 56 Black and 52 White students. The confluence model and parental occupation were deemed insufficient in accounting for racial differences in intelligence scores. (Author/JKS)

Foetal Ureaplasma parvum bacteraemia as a function of gestation-dependent complement insufficiency: Evidence from a sheep model of pregnancy.

PubMed

Kemp, Matthew W; Ahmed, Shatha; Beeton, Michael L; Payne, Matthew S; Saito, Masatoshi; Miura, Yuichiro; Usuda, Haruo; Kallapur, Suhas G; Kramer, Boris W; Stock, Sarah J; Jobe, Alan H; Newnham, John P; Spiller, Owen B

2017-01-01

Complement is a central defence against sepsis, and increasing complement insufficiency in neonates of greater prematurity may predispose to increased sepsis. Ureaplasma spp. are the most frequently cultured bacteria from preterm blood samples. A sheep model of intrauterine Ureaplasma parvum infection was used to examine in vivo Ureaplasma bacteraemia at early and late gestational ages. Complement function and Ureaplasma killing assays were used to determine the correlation between complement potency and bactericidal activity of sera ex vivo. Ureaplasma was cultured from 50% of 95-day gestation lamb cord blood samples compared to 10% of 125-day gestation lambs. Bactericidal activity increased with increased gestational age, and a direct correlation between functional complement activity and bactericidal activity (R 2 =.86; P<.001) was found for 95-day gestational lambs. Ureaplasma bacteraemia in vivo was confined to early preterm lambs with low complement function, but Ureaplasma infection itself did not diminish complement levels. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Impaired acid neutralization in the duodenum in pancreatic insufficiency.

PubMed

Dutta, S K; Russell, R M; Iber, F L

1979-10-01

The influence of severe exocrine pancreatic disease on the acid-neutralizing capacity of the duodenum was studied in five patients with pancreatic insufficiency (PI) and six control subjects using duodenal perfusion-marker technique. Hydrochloric acid (0.1 N containing 1% PEG) was infused at constant rates (1.2, 4.5 and 7.0 ml/min) into the duodenum just distal to the duodenal bulb. Samples were aspirated from the tip of the duodenal perfusion tube located at the ligament of Treitz. All samples were analyzed for volume, pH, titrable acidity, PEG and [14C]PEG (gastric marker) determination. Patients with PI demonstrated significantly diminished ability to neutralize various acid loads as compared to controls who virtually completely neutralized acid loads in the range of maximal gastric acid secretion. Exogenous secretin did not significantly improve percent acid neutralized in PI. These data clearly indicate that patients with PI have significantly impaired ability to neutralize even small loads of acid in the duodenum.

Flexible nano- and microliter injections on a single liquid chromatography-mass spectrometry system: Minimizing sample preparation and maximizing linear dynamic range.

PubMed

Lubin, Arnaud; Sheng, Sheng; Cabooter, Deirdre; Augustijns, Patrick; Cuyckens, Filip

2017-11-17

Lack of knowledge on the expected concentration range or insufficient linear dynamic range of the analytical method applied are common challenges for the analytical scientist. Samples that are above the upper limit of quantification are typically diluted and reanalyzed. The analysis of undiluted highly concentrated samples can cause contamination of the system, while the dilution step is time consuming and as the case for any sample preparation step, also potentially leads to precipitation, adsorption or degradation of the analytes. Copyright © 2017 Elsevier B.V. All rights reserved.

Insufficient coping behavior under chronic stress and vulnerability to psychiatric disorders.

PubMed

Mohr, Christine; Braun, Silke; Bridler, René; Chmetz, Florian; Delfino, Juan P; Kluckner, Viktoria J; Lott, Petra; Schrag, Yann; Seifritz, Erich; Stassen, Hans H

2014-01-01

Epidemiological data indicate that 75% of subjects with major psychiatric disorders have their onset of illness in the age range of 17-24 years. An estimated 35-50% of college and university students drop out prematurely due to insufficient coping skills under chronic stress, while 85% of students receiving a psychiatric diagnosis withdraw from college/university prior to the completion of their education. In this study, we aimed at developing standardized means of identifying students with insufficient coping skills under chronic stress and at risk for mental health problems. A sample of 1,217 college students from 3 different sites in the USA and Switzerland completed 2 self-report questionnaires: the Coping Strategies Inventory (COPE) and the Zurich Health Questionnaire (ZHQ), which assesses 'regular exercises', 'consumption behavior', 'impaired physical health', 'psychosomatic disturbances' and 'impaired mental health'. The data were subjected to structure analyses by means of a neural network approach. We found 2 highly stable and reproducible COPE scales that explained the observed interindividual variation in coping behavior sufficiently well and in a socioculturally independent way. The scales reflected basic coping behavior in terms of 'activity-passivity' and 'defeatism-resilience', and in the sense of stable, socioculturally independent personality traits. Correlation analyses carried out for external validation revealed a close relationship between high scores on the defeatism scale and impaired physical and mental health. This underlined the role of insufficient coping behavior as a risk factor for physical and mental health problems. The combined COPE and ZHQ instruments appear to constitute powerful screening tools for insufficient coping skills under chronic stress and for risks of mental health problems.

Galaxy evolution and large-scale structure in the far-infrared. II - The IRAS faint source survey

NASA Astrophysics Data System (ADS)

Lonsdale, Carol J.; Hacking, Perry B.; Conrow, T. P.; Rowan-Robinson, M.

1990-07-01

The new IRAS Faint Source Survey data base is used to confirm the conclusion of Hacking et al. (1987) that the 60 micron source counts fainter than about 0.5 Jy lie in excess of predictions based on nonevolving model populations. The existence of an anisotropy between the northern and southern Galactic caps discovered by Rowan-Robinson et al. (1986) and Needham and Rowan-Robinson (1988) is confirmed, and it is found to extend below their sensitivity limit to about 0.3 Jy in 60 micron flux density. The count anisotropy at f(60) greater than 0.3 can be interpreted reasonably as due to the Local Supercluster; however, no one structure accounting for the fainter anisotropy can be easily identified in either optical or far-IR two-dimensional sky distributions. The far-IR galaxy sky distributions are considerably smoother than distributions from the published optical galaxy catalogs. It is likely that structure of the large size discussed here have been discriminated against in earlier studies due to insufficient volume sampling.

Semi-automated Approach to Mapping Sub-hectare Agricultural Fields using Very High Resolution Data in a High-Performance Computing Environment

NASA Astrophysics Data System (ADS)

Wooten, M.; Neigh, C. S. R.; Carroll, M.; McCarty, J. L.

2017-12-01

In areas susceptible to drought such as sub-Saharan Africa, Crop Area (CA) and agricultural mapping have become increasingly important as strain on natural ecosystems increases. In Ethiopia alone, the population has grown four-fold in the last 70 years, and rapidly growing human populations bring added stress to ecosystems as more wildlands are converted to pastures and subsistence agriculture. Monitoring change in agriculture is one of the more essential goals of famine early warning systems. However, due to the sub-hectare size of rainfed agricultural fields in regions such as Tigray, Ethiopia, moderate resolution satellite imagery is insufficient at capturing these smallholder farms. Thanks to the increasing density of observations and ease of access to very high resolution (VHR) data, we have developed a generalized method for mapping CA with VHR data and have used this to generate wall-to-wall CA map for the entire Tigray region and samples in Myanmar, Senegal, and Vietnam. Here we present the methodology and early results as well as potential future applications.

Controlling Endemic Pathogens—Challenges and Opportunities

PubMed Central

Shankaran, Sunita S.; James, William L.

2016-01-01

Abstract By most measures, the University of Utah Centralized Zebrafish Animal Resource is a successful zebrafish core facility: we house ∼4000–5000 tanks for over 16 research groups; provide services and equipment for ∼150 users; are currently undergoing an expansion by 3000 tanks; and have been praised by institutional and national regulatory agencies for the cleanliness and efficiency of our facility. In recent years, we have implemented new programs to improve the overall health of our colony and believe we have seen a reduction in apparently sick fish. However, there are still deficiencies in our monitoring and pathogen control programs. Our histopathology sample sizes have been insufficient to estimate prevalence, but our sentinel tank program reveals the presence of Pseudoloma neurophilia and myxozoan, presumably Myxidium streisinger, in our facility. As we develop protocols to further reduce the burden of disease, we are focused on defining our baseline, establishing goals, and implementing methods to monitor our progress. The data generated by this approach will allow us to evaluate and implement the most cost-effective protocols to improve fish health. PMID:26982004

Exploring Relationships between Host Genome and Microbiome: New Insights from Genome-Wide Association Studies

PubMed Central

Abdul-Aziz, Muslihudeen A.; Cooper, Alan; Weyrich, Laura S.

2016-01-01

As our understanding of the human microbiome expands, impacts on health and disease continue to be revealed. Alterations in the microbiome can result in dysbiosis, which has now been linked to subsequent autoimmune and metabolic diseases, highlighting the need to identify factors that shape the microbiome. Research has identified that the composition and functions of the human microbiome can be influenced by diet, age, sex, and environment. More recently, studies have explored how human genetic variation may also influence the microbiome. Here, we review several recent analytical advances in this new research area, including those that use genome-wide association studies to examine host genome–microbiome interactions, while controlling for the influence of other factors. We find that current research is limited by small sample sizes, lack of cohort replication, and insufficient confirmatory mechanistic studies. In addition, we discuss the importance of understanding long-term interactions between the host genome and microbiome, as well as the potential impacts of disrupting this relationship, and explore new research avenues that may provide information about the co-evolutionary history of humans and their microorganisms. PMID:27785127

Galaxy evolution and large-scale structure in the far-infrared. II. The IRAS faint source survey

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

Lonsdale, C.J.; Hacking, P.B.; Conrow, T.P.

1990-07-01

The new IRAS Faint Source Survey data base is used to confirm the conclusion of Hacking et al. (1987) that the 60 micron source counts fainter than about 0.5 Jy lie in excess of predictions based on nonevolving model populations. The existence of an anisotropy between the northern and southern Galactic caps discovered by Rowan-Robinson et al. (1986) and Needham and Rowan-Robinson (1988) is confirmed, and it is found to extend below their sensitivity limit to about 0.3 Jy in 60 micron flux density. The count anisotropy at f(60) greater than 0.3 can be interpreted reasonably as due to themore » Local Supercluster; however, no one structure accounting for the fainter anisotropy can be easily identified in either optical or far-IR two-dimensional sky distributions. The far-IR galaxy sky distributions are considerably smoother than distributions from the published optical galaxy catalogs. It is likely that structure of the large size discussed here have been discriminated against in earlier studies due to insufficient volume sampling. 105 refs.« less

Galaxy evolution and large-scale structure in the far-infrared. II - The IRAS faint source survey

NASA Technical Reports Server (NTRS)

Lonsdale, Carol J.; Hacking, Perry B.; Conrow, T. P.; Rowan-Robinson, M.

1990-01-01

The new IRAS Faint Source Survey data base is used to confirm the conclusion of Hacking et al. (1987) that the 60 micron source counts fainter than about 0.5 Jy lie in excess of predictions based on nonevolving model populations. The existence of an anisotropy between the northern and southern Galactic caps discovered by Rowan-Robinson et al. (1986) and Needham and Rowan-Robinson (1988) is confirmed, and it is found to extend below their sensitivity limit to about 0.3 Jy in 60 micron flux density. The count anisotropy at f(60) greater than 0.3 can be interpreted reasonably as due to the Local Supercluster; however, no one structure accounting for the fainter anisotropy can be easily identified in either optical or far-IR two-dimensional sky distributions. The far-IR galaxy sky distributions are considerably smoother than distributions from the published optical galaxy catalogs. It is likely that structure of the large size discussed here have been discriminated against in earlier studies due to insufficient volume sampling.

The Impact of Uncertain Physical Parameters on HVAC Demand Response

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

Sun, Yannan; Elizondo, Marcelo A.; Lu, Shuai

HVAC units are currently one of the major resources providing demand response (DR) in residential buildings. Models of HVAC with DR function can improve understanding of its impact on power system operations and facilitate the deployment of DR technologies. This paper investigates the importance of various physical parameters and their distributions to the HVAC response to DR signals, which is a key step to the construction of HVAC models for a population of units with insufficient data. These parameters include the size of floors, insulation efficiency, the amount of solid mass in the house, and efficiency of the HVAC units.more » These parameters are usually assumed to follow Gaussian or Uniform distributions. We study the effect of uncertainty in the chosen parameter distributions on the aggregate HVAC response to DR signals, during transient phase and in steady state. We use a quasi-Monte Carlo sampling method with linear regression and Prony analysis to evaluate sensitivity of DR output to the uncertainty in the distribution parameters. The significance ranking on the uncertainty sources is given for future guidance in the modeling of HVAC demand response.« less

Statistical robustness of machine-learning estimates for characterizing a groundwater-surface water system, Southland, New Zealand

NASA Astrophysics Data System (ADS)

Friedel, M. J.; Daughney, C.

2016-12-01

The development of a successful surface-groundwater management strategy depends on the quality of data provided for analysis. This study evaluates the statistical robustness when using a modified self-organizing map (MSOM) technique to estimate missing values for three hypersurface models: synoptic groundwater-surface water hydrochemistry, time-series of groundwater-surface water hydrochemistry, and mixed-survey (combination of groundwater-surface water hydrochemistry and lithologies) hydrostratigraphic unit data. These models of increasing complexity are developed and validated based on observations from the Southland region of New Zealand. In each case, the estimation method is sufficiently robust to cope with groundwater-surface water hydrochemistry vagaries due to sample size and extreme data insufficiency, even when >80% of the data are missing. The estimation of surface water hydrochemistry time series values enabled the evaluation of seasonal variation, and the imputation of lithologies facilitated the evaluation of hydrostratigraphic controls on groundwater-surface water interaction. The robust statistical results for groundwater-surface water models of increasing data complexity provide justification to apply the MSOM technique in other regions of New Zealand and abroad.

The relation of female circumcision to sexual behavior in Kenya and Nigeria.

PubMed

Mpofu, Sibonginkosi; Odimegwu, Clifford; De Wet, Nicole; Adedini, Sunday; Akinyemi, Joshua

2017-08-01

One of the reasons for the perpetuation of female circumcision is that it controls female sexuality. In this study, the authors examined the relationship between female circumcision and the sexual behavior of women in Kenya and Nigeria. Data on women who were aware of circumcision and were circumcised were extracted from the Kenya Demographic and Health Survey of 2008-09 as well as the Nigeria Demographic and Health Survey of 2008. The sample size was 7,344 for Kenya and 16,294 for Nigeria. The outcome variables were age at first intercourse and total lifetime number of sexual partners. The study hypothesis was that women who were circumcised were less likely to have initiated sex early and to have only one sex partner. Cox proportional hazards regression and Poisson regression were used to examine the relations of female circumcision and other selected variables to sexual behavior. No association was observed between female circumcision and the outcomes for sexual behavior of women in Kenya and Nigeria. The argument of sexual chastity is insufficient to sustain the perpetuation of female circumcision.

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.

Multislice spiral CT simulator for dynamic cardiopulmonary studies

NASA Astrophysics Data System (ADS)

De Francesco, Silvia; Ferreira da Silva, Augusto M.

2002-04-01

We've developed a Multi-slice Spiral CT Simulator modeling the acquisition process of a real tomograph over a 4-dimensional phantom (4D MCAT) of the human thorax. The simulator allows us to visually characterize artifacts due to insufficient temporal sampling and a priori evaluate the quality of the images obtained in cardio-pulmonary studies (both with single-/multi-slice and ECG gated acquisition processes). The simulating environment allows both for conventional and spiral scanning modes and includes a model of noise in the acquisition process. In case of spiral scanning, reconstruction facilities include longitudinal interpolation methods (360LI and 180LI both for single and multi-slice). Then, the reconstruction of the section is performed through FBP. The reconstructed images/volumes are affected by distortion due to insufficient temporal sampling of the moving object. The developed simulating environment allows us to investigate the nature of the distortion characterizing it qualitatively and quantitatively (using, for example, Herman's measures). Much of our work is focused on the determination of adequate temporal sampling and sinogram regularization techniques. At the moment, the simulator model is limited to the case of multi-slice tomograph, being planned as a next step of development the extension to cone beam or area detectors.

Characterization of Bacterial Communities in Venous Insufficiency Wounds by Use of Conventional Culture and Molecular Diagnostic Methods▿

PubMed Central

Tuttle, Marie S.; Mostow, Eliot; Mukherjee, Pranab; Hu, Fen Z.; Melton-Kreft, Rachael; Ehrlich, Garth D.; Dowd, Scot E.; Ghannoum, Mahmoud A.

2011-01-01

Microbial infections delay wound healing, but the effect of the composition of the wound microbiome on healing parameters is unknown. To better understand bacterial communities in chronic wounds, we analyzed debridement samples from lower-extremity venous insufficiency ulcers using the following: conventional anaerobic and aerobic bacterial cultures; the Ibis T5000 universal biosensor (Abbott Molecular); and 16S 454 FLX titanium series pyrosequencing (Roche). Wound debridement samples were obtained from 10 patients monitored clinically for at least 6 months, at which point 5 of the 10 sampled wounds had healed. Pyrosequencing data revealed significantly higher bacterial abundance and diversity in wounds that had not healed at 6 months. Additionally, Actinomycetales was increased in wounds that had not healed, and Pseudomonadaceae was increased in wounds that had healed by the 6-month follow-up. Baseline wound surface area, duration, or analysis by Ibis or conventional culture did not reveal significant differences between wounds that healed after 6 months and those that did not. Thus, pyrosequencing identified distinctive baseline characteristics of wounds that did not heal by the 6-month follow-up, furthering our understanding of potentially unique microbiome characteristics of chronic wounds. PMID:21880958

Blood collected on filter paper for wildlife serology: detecting antibodies to Neospora caninum, West Nile virus, and five bovine viruses in reindeer.

PubMed

Curry, Patricia S; Ribble, Carl; Sears, William C; Hutchins, Wendy; Orsel, Karin; Godson, Dale; Lindsay, Robbin; Dibernardo, Antonia; Kutz, Susan J

2014-04-01

We compared Nobuto filter paper (FP) whole-blood samples to serum for detecting antibodies to seven pathogens in reindeer (Rangifer tarandus tarandus). Serum and FP samples were collected from captive reindeer in 2008-2009. Sample pairs (serum and FP eluates) were assayed in duplicate at diagnostic laboratories with the use of competitive enzyme-linked immunosorbent assays (cELISAs) for Neospora caninum and West Nile virus (WNV); indirect ELISA (iELISAs) for bovine herpesvirus type 1 (BHV-1), parainfluenza virus type 3 (PI-3), and bovine respiratory syncytial virus (BRSV); and virus neutralization (VN) for bovine viral diarrhea virus (BVDV) types I and II. Assay thresholds were evidence-based values employed by each laboratory. Comparable performance to serum was defined as FP sensitivity and specificity ≥ 80%. Filter-paper specificity estimates ranged from 92% in the cELISAs for N. caninum and WNV to 98% in the iELISAs for PI-3 and BRSV. Sensitivity was >85% for five tests (most ≥ 95%) but was insufficient (71-82%) for the PI-3 and BRSV iELISAs. Lowering the threshold for FP samples in these two ELISAs raised sensitivity to ≥ 87% and reduced specificity slightly (≥ 90% in three of the four test runs). Sample size limited the precision of some performance estimates. Based on the criteria of sensitivity and specificity ≥ 80%, and using adjusted FP thresholds for PI-3 and BRSV, FP sensitivity and specificity were comparable to serum in all seven assays. A potential limitation of FP is reduced sensitivity in tests that require undiluted serum (i.e., N. caninum cELISA and BVDV VNs). Possible toxicity to the assay cell layer in VN requires investigation. Results suggested that cELISA is superior to iELISA for detecting antibodies in FP samples from reindeer and other Rangifer tarandus subspecies. Our findings expand the potential utility of FP sampling from wildlife.

Towards an Early Software Effort Estimation Based on Functional and Non-Functional Requirements

NASA Astrophysics Data System (ADS)

Kassab, Mohamed; Daneva, Maya; Ormandjieva, Olga

The increased awareness of the non-functional requirements as a key to software project and product success makes explicit the need to include them in any software project effort estimation activity. However, the existing approaches to defining size-based effort relationships still pay insufficient attention to this need. This paper presents a flexible, yet systematic approach to the early requirements-based effort estimation, based on Non-Functional Requirements ontology. It complementarily uses one standard functional size measurement model and a linear regression technique. We report on a case study which illustrates the application of our solution approach in context and also helps evaluate our experiences in using it.

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.

Screening for Chlamydial Cervicitis in a Sexually Active University Population.

ERIC Educational Resources Information Center

Malotte, C. Kevin; And Others

1990-01-01

Enzyme-linked immunoabsorbent assays to detect chlamydial cervicitis were performed on samples from 1,320 sexually active university women. Seventy-five had positive tests. Demographic, history, symptom, and physical examination variables were insufficient to predict infection accurately. Concludes that screening during routine visits with this…

Teaching Math Online: Current Practices in Turkey

ERIC Educational Resources Information Center

Akdemir, Omur

2011-01-01

Changing nature of student population, developments in technology, and insufficient number of traditional universities have made online courses popular around the globe. This study was designed to investigate the current practices of teaching mathematics online in Turkish Universities through a qualitative inquiry. The snowball sampling method was…

Cognitive Tests in Early Childhood: Psychometric and Cultural Considerations

ERIC Educational Resources Information Center

Williams, Marian E.; Sando, Lara; Soles, Tamara Glen

2014-01-01

Cognitive assessment of young children contributes to high-stakes decisions because results are often used to determine eligibility for early intervention and special education. Previous reviews of cognitive measures for young children highlighted concerns regarding adequacy of standardization samples, steep item gradients, and insufficient floors…

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 notion of snow grain shape: Ambiguous definitions, retrievalfrom tomography and implications on remote sensing

NASA Astrophysics Data System (ADS)

Krol, Q. E.; Loewe, H.

2016-12-01

Grain shape is known to influence the effective physical properties of snow and therefore included in the international classification of seasonal snow. Accordingly, snowpack models account for phenomenological shape parameters (sphericity, dendricity) to capture shape variations. These parameters are however difficult to validate due to the lack of clear-cut definitions from the 3D microstucture and insufficient links to physical properties. While the definition of traditional shape was tailored to the requirements of observers, a more objective definition should be tailored to the requirements of physical properties, by analyzing geometrical (shape) corrections in existing theoretical formulations directly. To this end we revisited the autocorrelation function (ACF) and the chord length distribution (CLD) of snow. Both functions capture size distributions of the microstructure, can be calculated from X-ray tomography and are related to various physical properties. Both functions involve the optical equivalent diameter as dominant quantity, however the respective higher-order geometrical correction differ. We have analyzed these corrections, namely interfacial curvatures for the ACF and the second moment for the CLD, using an existing data set of 165 tomography samples. To unify the notion of shape, we derived various statistical relations between the length scales. Our analysis bears three key practical implications. First, we derived a significantly improved relation between the exponential correlation length and the optical diameter by taking curvatures into account. This adds to the understanding of linking "microwave grain size" and "optical grain size" of snow for remote sensing. Second, we retrieve the optical shape parameter (commonly referred to as B) from tomography images via the moment of the CLD. Third, shape variations seen by observers do not necessarily correspond to shape variations probed by physical properties.

Failure Rate of Direct High-Viscosity Glass-Ionomer Versus Hybrid Resin Composite Restorations in Posterior Permanent Teeth - a Systematic Review

PubMed Central

Mickenautsch, Steffen; Yengopal, Veerasamy

2015-01-01

Purpose Traditionally, resin composite restorations are claimed by reviews of the dental literature as being superior to glass-ionomer fillings in terms of restoration failures in posterior permanent teeth. The aim of this systematic review is to answer the clinical question, whether conventional high-viscosity glass-ionomer restorations, in patients with single and/or multi-surface cavities in posterior permanent teeth, have indeed a higher failure rate than direct hybrid resin composite restorations. Methods Eight databases were searched until December 02, 2013. Trials were assessed for bias risks, in-between datasets heterogeneity and statistical sample size power. Effects sizes were computed and statistically compared. A total of 55 citations were identified through systematic literature search. From these, 46 were excluded. No trials related to high-viscosity glass-ionomers versus resin composite restorations for direct head-to-head comparison were found. Three trials related to high-viscosity glass-ionomers versus amalgam and three trials related to resin composite versus amalgam restorations could be included for adjusted indirect comparison, only. Results The available evidence suggests no difference in the failure rates between both types of restoration beyond the play of chance, is limited by lack of head-to-head comparisons and an insufficient number of trials, as well as by high bias and in-between-dataset heterogeneity risk. The current clinical evidence needs to be regarded as too poor in order to justify superiority claims regarding the failure rates of both restoration types. Sufficiently large-sized, parallel-group, randomised control trials with high internal validity are needed, in order to justify any clinically meaningful judgment to this topic. PMID:26962372

An improved assay for the determination of Huntington`s disease allele size

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

Reeves, C.; Klinger, K.; Miller, G.

1994-09-01

The hallmark of Huntington`s disease (HD) is the expansion of a polymorphic (CAG)n repeat. Several methods have been published describing PCR amplification of this region. Most of these assays require a complex PCR reaction mixture to amplify this GC-rich region. A consistent problem with trinucleotide repeat PCR amplification is the presence of a number of {open_quotes}stutter bands{close_quotes} which may be caused by primer or amplicon slippage during amplification or insufficient polymerase processivity. Most assays for HD arbitrarily select a particular band for diagnostic purposes. Without a clear choice for band selection such an arbitrary selection may result in inconsistent intra-more » or inter-laboratory findings. We present an improved protocol for the amplification of the HD trinucleotide repeat region. This method simplifies the PCR reaction buffer and results in a set of easily identifiable bands from which to determine allele size. HD alleles were identified by selecting bands of clearly greater signal intensity. Stutter banding was much reduced thus permitting easy identification of the most relevant PCR product. A second set of primers internal to the CCG polymorphism was used in selected samples to confirm allele size. The mechanism of action of N,N,N trimethylglycine in the PCR reaction is not clear. It may be possible that the minimal isostabilizing effect of N,N,N trimethylglycine at 2.5 M is significant enough to affect primer specificity. The use of N,N,N trimethylglycine in the PCR reaction facilitated identification of HD alleles and may be appropriate for use in other assays of this type.« less

Evaluation of the new restandardized Abbott Architect 25-OH Vitamin D assay in vitamin D-insufficient and vitamin D-supplemented individuals.

PubMed

Annema, Wijtske; Nowak, Albina; von Eckardstein, Arnold; Saleh, Lanja

2017-09-19

Recently, Abbott Diagnostics has restandardized the Architect 25(OH)D assay against the NIST SRM 2972. We have evaluated the analytical and clinical performance of the restandardized Architect 25(OH)D assay and compared its performance with a NIST-traceable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and the Roche total 25(OH)D assay in vitamin D-insufficient individuals before and after vitamin D 3 supplementation. Frozen serum samples were obtained from 88 healthy subjects with self-perceived fatigue and vitamin D-insufficiency <50 nmol L -1 who were randomized to receive a single 100 000 IU dose of vitamin D 3 (n = 48) or placebo (n = 40). Total 25(OH)D concentrations were measured before and 4 weeks after supplementation by the restandardized Architect 25(OH)D assay, LC-MS/MS, and Roche assay. The Architect 25(OH)D assay showed an intra- and inter-assay imprecision of <5%. Comparison of the Architect assay with the LC-MS/MS method showed a good correlation in both vitamin D-insufficient and vitamin D-supplemented subjects, however, with a negative mean bias of 17.4% and 8.9%, respectively. As compared to the Roche assay, the Abbott assay underestimated 25(OH)D results in insufficient subjects (<50 nmol L -1 ) with a mean negative bias of 17.1%, this negative bias turned into a positive bias in supplemented subjects. Overall there was a moderate agreement in classification of vitamin D-insufficient and -supplemented individuals into different vitamin D states between the Architect 25(OH)D method and LC-MS/MS. The routine use of the restandardized Architect 25(OH)D results in a slight underestimation of circulating total 25(OH)D levels at lower concentrations and thus potential misclassification of vitamin D status. © 2017 Wiley Periodicals, Inc.

The High Prevalence of Vitamin D Insufficiency in Cord Blood in Calgary, Alberta (APrON-D Study).

PubMed

Aghajafari, Fariba; Field, Catherine J; Kaplan, Bonnie J; Maggiore, Jack A; O'Beirne, Maeve; Hanley, David A; Eliasziw, Misha; Dewey, Deborah; Ross, Sue; Rabi, Doreen

2017-05-01

Vitamin D is important in promoting healthy pregnancy and fetal development. We undertook this study to measure 25-hydroxyvitamin D in maternal and cord blood and to identify maternal factors related to vitamin D status in Calgary. Blood samples collected at the time of delivery from the Alberta Pregnancy Outcomes and Nutrition study cohort (ApronStudy.ca) participants were processed for plasma and assayed using liquid chromatography mass spectrometry methodology for 25(OH)D 3 . Ninety-two pairs of maternal and cord blood samples were obtained. The prevalence of 25(OH)D 3 insufficiency-25(OH)D 3 <75 nmol/L-was 38% and 80% in women and neonates, respectively. Vitamin D supplementation was the only clinical factor associated with 25(OH)D 3 sufficiency, and the odds of sufficiency were 3.75 (95% CI 1.00 to 14.07) higher for women and 5.27 (95% CI 1.37 to 20.27) when over 2000 IU/day were used. Using liquid chromatography mass spectrometry, we demonstrated a very high prevalence of vitamin D insufficiency in cord blood and that the use of high dose vitamin D was associated with greater odds of sufficiency in pregnant women and cord blood in Alberta. Copyright © 2017 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.

Influence of feedstock particle size on lignocellulose conversion--a review.

PubMed

Vidal, Bernardo C; Dien, Bruce S; Ting, K C; Singh, Vijay

2011-08-01

Feedstock particle sizing can impact the economics of cellulosic ethanol commercialization through its effects on conversion yield and energy cost. Past studies demonstrated that particle size influences biomass enzyme digestibility to a limited extent. Physical size reduction was able to increase conversion rates to maximum of ≈ 50%, whereas chemical modification achieved conversions of >70% regardless of biomass particle size. This suggests that (1) mechanical pretreatment by itself is insufficient to attain economically feasible biomass conversion, and, therefore, (2) necessary particle sizing needs to be determined in the context of thermochemical pretreatment employed for lignocellulose conversion. Studies of thermochemical pretreatments that have taken into account particle size as a factor have exhibited a wide range of maximal sizes (i.e., particle sizes below which no increase in pretreatment effectiveness, measured in terms of the enzymatic conversion resulting from the pretreatment, were observed) from <0.15 to 50 mm. Maximal sizes as defined above were dependent on the pretreatment employed, with maximal size range decreasing as follows: steam explosion > liquid hot water > dilute acid and base pretreatments. Maximal sizes also appeared dependent on feedstock, with herbaceous or grassy biomass exhibiting lower maximal size range (<3 mm) than woody biomass (>3 mm). Such trends, considered alongside the intensive energy requirement of size reduction processes, warrant a more systematic study of particle size effects across different pretreatment technologies and feedstock, as a requisite for optimizing the feedstock supply system.

Psychosocial work factors and sleep problems: findings from the French national SIP survey.

PubMed

Chazelle, Emilie; Chastang, Jean-François; Niedhammer, Isabelle

2016-04-01

This study aimed at exploring the cross-sectional and prospective associations between psychosocial work factors and sleep problems. The study population consisted of a national representative sample of the French working population (SIP survey). The sample sizes were 7506 and 3555 for the cross-sectional and prospective analyses. Sleep problems were defined by either sleep disturbances or insufficient sleep duration at least several times a week. Psychosocial work factors included classical (job strain model factors) and emergent factors (recognition, insecurity, role/ethical conflict, emotional demands, work-life imbalance, etc.). Occupational factors related to working time/hours and physical work environment were also included as well as covariates related to factors outside work. Statistical analyses were performed using weighted Poisson regression analysis. In the cross-sectional analyses, psychological demands, low social support, low recognition, emotional demands, perception of danger, work-life imbalance and night work were found to be associated with sleep problems. In the prospective analyses, psychological demands and night work were predictive of sleep problems. Using a less conservative method, more factors were found to be associated with sleep problems. Dose-response associations were observed, showing that the more frequent the exposure to these factors, the higher the risk of sleep problems. No effect of repeated exposure was found on sleep problems. Classical and emergent psychosocial work factors were associated with sleep problems. More prospective studies and prevention policies may be needed.

[Psychostimulants for late life depression].

PubMed

Delsalle, P; Schuster, J-P; von Gunten, A; Limosin, F

2017-11-28

The use of psychostimulants in the treatment of depressive disorders is receiving renewed interest. Recent publications suggest a particular interest of psychostimulants in the treatment of depression in the elderly. The aim of this article is to review the literature on the role of psychostimulants in the treatment of depression in older adults. The literature review focused on efficacy and tolerability studies of psychostimulants in the treatment of depression for the elderly that were published between 1980 and 2016. The only inclusion criterion applied was an average age of the sample studied greater than or equal to 60 years. Overall, 12 trials were selected: 3 controlled trials and 9 uncontrolled trials. Of the 3 controlled trials, one compared parallel groups and the other two were cross-tests. Among the psychostimulants, methylphenidate was the most studied molecule. The trials demonstrate an efficacy of this molecule in particular as an add-on therapy in old-age depression but for the most part with a level of proof that remains insufficient. The small size of the samples and the methodological limitations of the studies obviate the possibility of extracting definitive conclusions concerning the place of psychostimulants in the treatment of depression in the elderly. Further studies are required in particular in the treatment of resistant depressive episodes. Copyright © 2017 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Doctors' opinions on clinical coordination between primary and secondary care in the Catalan healthcare system.

PubMed

Aller, Marta-Beatriz; Vargas, Ingrid; Coderch, Jordi; Calero, Sebastià; Cots, Francesc; Abizanda, Mercè; Colomés, Lluís; Farré, Joan; Vázquez-Navarrete, María-Luisa

2017-08-26

To analyse doctors' opinions on clinical coordination between primary and secondary care in different healthcare networks and on the factors influencing it. A qualitative descriptive-interpretative study was conducted, based on semi-structured interviews. A two-stage theoretical sample was designed: 1) healthcare networks with different management models; 2) primary care and secondary care doctors in each network. Final sample size (n = 50) was reached by saturation. A thematic content analysis was conducted. In all networks doctors perceived that primary and secondary care given to patients was coordinated in terms of information transfer, consistency and accessibility to SC following a referral. However, some problems emerged, related to difficulties in acceding non-urgent secondary care changes in prescriptions and the inadequacy of some referrals across care levels. Doctors identified the following factors: 1) organizational influencing factors: coordination is facilitated by mechanisms that facilitate information transfer, communication, rapid access and physical proximity that fosters positive attitudes towards collaboration; coordination is hindered by the insufficient time to use mechanisms, unshared incentives in prescription and, in two networks, the change in the organizational model; 2) professional factors: clinical skills and attitudes towards coordination. Although doctors perceive that primary and secondary care is coordinated, they also highlighted problems. Identified factors offer valuable insights on where to direct organizational efforts to improve coordination. Copyright © 2017. Publicado por Elsevier España, S.L.U.

[Clinical implications and angiographic and electrocardiographic correlation of ST segment elevation in leads V7-V9 in patients with ST elevation myocardial infarction].

PubMed

Adawi, Khaled; Atar, Shaul

2008-07-01

The clinical significance and clinical characteristics of patients with myocardial infarction involving the posterior wall of the left ventricle is not well-defined. The angiographic findings and their correlation with the eletrocardiographic (ECG) findings may be of high therapeutic importance. We retrospectively studied consecutive patients with ST elevation myocardial infarction on the admission ECG to the intensive cardiac care. We studied the clinical and demographic characteristics, the clinical course in-hospital and the clinical outcome (including infarct size, congestive heart failure and significant mitral insufficiency). All patients underwent coronary angiography during the index admission. We correlated the ECG findings on admission to the angiographic findings. We studied 198 patients with mean age of 57 +/- 12 years (range 30-88 years), 158 men (79.8%) and 40 women (20.2%). Myocardial infarction involving the inferior wall was noted in 119 patients, of whom 68 had inferior wall myocardial infarction only, and 51 had inferior and lateral wall involvement (leads I, AVL and/or V5-V6). Only 4 patients (2%) had ST elevation in leads V7-V9 only. The left ventricular ejection fraction was lowest in patients with anterior wall myocardial infarction (41% +/- 6) compared to myocardial infarction with the posterior wall involved (44% +/- 8) or myocardial infarction with the inferior wall only (54% +/- 6) (p = 0.023). The largest infarct size by peak creatine phosphokinase was found in the inferoposterior myocardial infarction group, significantly larger from inferior infarction only, and similar to that of anterior myocardial infarction. The incidence of congestive heart failure was slightly more in anterior myocardial infarction; however, significant mitral valve insufficiency was higher in patients with posterior wall involvement, yet with no statistical significance. The infarct related artery causing posterior myocardial infarction was significantly more frequent in the right coronary artery (57.1%) compared to the left circumflex artery (37.5%) (p < 0.01). The major artery causing involvement of the posterior wall is the right coronary artery. In patients with myocardial infarction involving the posterior wall, infarct size is similar to that of anterior wall myocardial infarction, and with similar complications rate. However, the incidence of significant mitral valve insufficiency and congestive heart failure is high in patients with posterior wall involvement. Posterior leads assessment should be conducted routinely in patients with suspected myocardial infarction.

Small-size pedestrian detection in large scene based on fast R-CNN

NASA Astrophysics Data System (ADS)

Wang, Shengke; Yang, Na; Duan, Lianghua; Liu, Lu; Dong, Junyu

2018-04-01

Pedestrian detection is a canonical sub-problem of object detection with high demand during recent years. Although recent deep learning object detectors such as Fast/Faster R-CNN have shown excellent performance for general object detection, they have limited success for small size pedestrian detection in large-view scene. We study that the insufficient resolution of feature maps lead to the unsatisfactory accuracy when handling small instances. In this paper, we investigate issues involving Fast R-CNN for pedestrian detection. Driven by the observations, we propose a very simple but effective baseline for pedestrian detection based on Fast R-CNN, employing the DPM detector to generate proposals for accuracy, and training a fast R-CNN style network to jointly optimize small size pedestrian detection with skip connection concatenating feature from different layers to solving coarseness of feature maps. And the accuracy is improved in our research for small size pedestrian detection in the real large scene.

Overestimation of body size in eating disorders and its association to body-related avoidance behavior.

PubMed

Vossbeck-Elsebusch, Anna N; Waldorf, Manuel; Legenbauer, Tanja; Bauer, Anika; Cordes, Martin; Vocks, Silja

2015-06-01

Body-related avoidance behavior, e.g., not looking in the mirror, is a common feature of eating disorders. It is assumed that it leads to insufficient feedback concerning one's own real body form and might thus contribute to distorted mental representation of one's own body. However, this assumption still lacks empirical foundation. Therefore, the aim of the present study was to examine the relationship between misperception of one's own body and body-related avoidance behavior in N = 78 female patients with Bulimia nervosa and eating disorder not otherwise specified. Body-size misperception was assessed using a digital photo distortion technique based on an individual picture of each participant which was taken in a standardized suit. In a regression analysis with body-related avoidance behavior, body mass index and weight and shape concerns as predictors, only body-related avoidance behavior significantly contributed to the explanation of body-size overestimation. This result supports the theoretical assumption that body-related avoidance behavior makes body-size overestimation more likely.

Spatial distribution patterns of soil mite communities and their relationships with edaphic factors in a 30-year tillage cornfield in northeast China.

PubMed

Liu, Jie; Gao, Meixiang; Liu, Jinwen; Guo, Yuxi; Liu, Dong; Zhu, Xinyu; Wu, Donghui

2018-01-01

Spatial distribution is an important topic in community ecology and a key to understanding the structure and dynamics of populations and communities. However, the available information related to the spatial patterns of soil mite communities in long-term tillage agroecosystems remains insufficient. In this study, we examined the spatial patterns of soil mite communities to explain the spatial relationships between soil mite communities and soil parameters. Soil fauna were sampled three times (August, September and October 2015) at 121 locations arranged regularly within a 400 m × 400 m monitoring plot. Additionally, we estimated the physical and chemical parameters of the same sampling locations. The distribution patterns of the soil mite community and the edaphic parameters were analyzed using a range of geostatistical tools. Moran's I coefficient showed that, during each sampling period, the total abundance of the soil mite communities and the abundance of the dominant mite populations were spatially autocorrelated. The soil mite communities demonstrated clear patchy distribution patterns within the study plot. These patterns were sampling period-specific. Cross-semivariograms showed both negative and positive cross-correlations between soil mite communities and environmental factors. Mantel tests showed a significant and positive relationship between soil mite community and soil organic matter and soil pH only in August. This study demonstrated that in the cornfield, the soil mite distribution exhibited strong or moderate spatial dependence, and the mites formed patches with sizes less than one hundred meters. In addition, in this long-term tillage agroecosystem, soil factors had less influence on the observed pattern of soil mite communities. Further experiments that take into account human activity and spatial factors should be performed to study the factors that drive the spatial distribution of soil microarthropods.

The brightest galaxies in the first 700 Myr: Building Hubble's legacy of large area IR imaging for JWST and beyond

NASA Astrophysics Data System (ADS)

Trenti, Michele

2017-08-01

Hubble's WFC3 has been a game changer for the study of early galaxy formation in the first 700 Myr after the Big Bang. Reliable samples of sources to redshift z 11, which can be discovered only from space, are now constraining the evolution of the galaxy luminosity function into the epoch of reionization. Unexpectedly but excitingly, the recent spectroscopic confirmations of L>L* galaxies at z>8.5 demonstrate that objects brighter than our own Galaxy are already present 500 Myr after the Big Bang, creating a challenge to current theoretical/numerical models that struggle to explain how galaxies can grow so luminous so quickly. Yet, the existing HST observations do not cover sufficient area, nor sample a large enough diversity of environments to provide an unbiased sample of sources, especially at z 9-11 where only a handful of bright candidates are known. To double this currently insufficient sample size, to constrain effectively the bright-end of the galaxy luminosity function at z 9-10, and to provide targets for follow-up imaging and spectroscopy with JWST, we propose a large-area pure-parallel survey that will discover the Brightest of Reionizing Galaxies (BoRG[4JWST]). We will observe 580 arcmin^2 over 125 sightlines in five WFC3 bands (0.35 to 1.7 micron) using high-quality pure-parallel opportunities available in the cycle (3 orbits or longer). These public observations will identify more than 80 intrinsically bright galaxies at z 8-11, investigate the connection between halo mass, star formation and feedback in progenitors of groups and clusters, and build HST lasting legacy of large-area, near-IR imaging.

Simulations inform design of regional occupancy-based monitoring for a sparsely distributed, territorial species

Treesearch

Quresh S. Latif; Martha M. Ellis; Victoria A. Saab; Kim Mellen-McLean

2017-01-01

Sparsely distributed species attract conservation concern, but insufficient information on population trends challenges conservation and funding prioritization. Occupancy-based monitoring is attractive for these species, but appropriate sampling design and inference depend on particulars of the study system. We employed spatially explicit simulations to identify...

Differentiation and classification of bacteria using vancomycin functionalized silver nanorods array based surface-enhanced raman spectroscopy an chemometric analysis

USDA-ARS?s Scientific Manuscript database

The intrinsic surface-enhanced Raman scattering (SERS) was used for differentiating and classifying bacterial species with chemometric data analysis. Such differentiation has often been conducted with an insufficient sample population and strong interference from the food matrices. To address these ...

Phylogenetics of a fungal invasion: origins and widespread dispersal of white-nose syndrome

Treesearch

Kevin P. Drees; Jeffrey M. Lorch; Sebastien J. Puechmaille; Katy L. Parise; Gudrun Wibbelt; Joseph R. Hoyt; Keping Sun; Ariunbold Jargalsaikhan; Munkhnast Dalannast; Jonathan M. Palmer; Daniel L. Lindner; A. Marm Kilpatrick; Talima Pearson; Paul S. Keim; David S. Blehert; Jeffrey T. Foster; Joseph Heitman

2017-01-01

Globalization has facilitated the worldwide movement and introduction of pathogens, but epizoological reconstructions of these invasions are often hindered by limited sampling and insufficient genetic resolution among isolates. Pseudogymnoascus destructans, a fungal pathogen causing the epizootic of white-nose syndrome in North American bats, has...

Restraint Theory: The Search for a Mechanism.

ERIC Educational Resources Information Center

Lowe, Michael R.

A review of research indicates that cognitive restraint is insufficient in accounting for the relationship between restraint and negative affect eating. To explore what mechanism may be responsible for restraint effects, college students in two samples (Total N=378) completed the Three-Factor Eating Questionnaire (TEQ), a restraint scale…

Vitamin D in patients with intellectual and developmental disability in secure in-patient services in the North of England, UK.

PubMed

McKinnon, Iain; Lewis, Thomas; Mehta, Naomi; Imrit, Shahed; Thorp, Julie; Ince, Chris

2018-02-01

Aims and method To assess the benefits of the introduction of routine vitamin D serum sampling for all patients admitted to a secure in-patient hospital in the North of England providing medium security, low security and rehabilitation services for offenders with intellectual and developmental disability. The vitamin D levels of 100 patients were analysed at baseline. Those with insufficient or deficient levels were offered treatment and retested after 1 year. Vitamin D levels were analysed in the context of level of security, seasonality of test and co-prescription of psychotropic medications. Eighty-three per cent of patients had suboptimal vitamin D levels at initial test (41% deficient and 42% insufficient). This was seen among established patients and new admissions. Regression analysis of baseline vitamin D levels revealed no differences for levels of security, seasonality, whether patients were taking antipsychotic or anticonvulsant medication, or length of stay. Patients with deficiency or insufficiency were all offered supplementation. Those who opted in had significantly higher vitamin D levels at follow-up, compared with those who declined treatment. Clinical implications Established and newly admitted patients in our secure mental health services had substantial levels of vitamin D insufficiency. In the light of the morbidities that are associated with deficient vitamin D levels, routine screening and the offer of supplementation is advisable. Declaration of interest None.

Analysis of Chinese women with primary ovarian insufficiency by high resolution array-comparative genomic hybridization.

PubMed

Liao, Can; Fu, Fang; Yang, Xin; Sun, Yi-Min; Li, Dong-Zhi

2011-06-01

Primary ovarian insufficiency (POI) is defined as a primary ovarian defect characterized by absent menarche (primary amenorrhea) or premature depletion of ovarian follicles before the age of 40 years. The etiology of primary ovarian insufficiency in human female patients is still unclear. The purpose of this study is to investigate the potential genetic causes in primary amenorrhea patients by high resolution array based comparative genomic hybridization (array-CGH) analysis. Following the standard karyotyping analysis, genomic DNA from whole blood of 15 primary amenorrhea patients and 15 normal control women was hybridized with Affymetrix cytogenetic 2.7M arrays following the standard protocol. Copy number variations identified by array-CGH were confirmed by real time polymerase chain reaction. All the 30 samples were negative by conventional karyotyping analysis. Microdeletions on chromosome 17q21.31-q21.32 with approximately 1.3 Mb were identified in four patients by high resolution array-CGH analysis. This included the female reproductive secretory pathway related factor N-ethylmaleimide-sensitive factor (NSF) gene. The results of the present study suggest that there may be critical regions regulating primary ovarian insufficiency in women with a 17q21.31-q21.32 microdeletion. This effect might be due to the loss of function of the NSF gene/genes within the deleted region or to effects on contiguous genes.

Lifestyle physical activity among urban Palestinians and Israelis: a cross-sectional comparison in the Palestinian-Israeli Jerusalem risk factor study

PubMed Central

2012-01-01

Background Urban Palestinians have a high incidence of coronary heart disease, and alarming prevalences of obesity (particularly among women) and diabetes. An active lifestyle can help prevent these conditions. Little is known about the physical activity (PA) behavior of Palestinians. This study aimed to determine the prevalence of insufficient PA and its socio-demographic correlates among urban Palestinians in comparison with Israelis. Methods An age-sex stratified random sample of Palestinians and Israelis aged 25-74 years living in east and west Jerusalem was drawn from the Israel National Population Registry: 970 Palestinians and 712 Israelis participated. PA in a typical week was assessed by the Multi-Ethnic Study of Atherosclerosis (MESA) questionnaire. Energy expenditure (EE), calculated in metabolic equivalents (METs), was compared between groups for moderate to vigorous-intensity physical activity (MVPA), using the Wilcoxon rank-sum test, and for domain-specific prevalence rates of meeting public health guidelines and all-domain insufficient PA. Correlates of insufficient PA were assessed by multivariable logistic modeling. Results Palestinian men had the highest median of MVPA (4740 METs-min*wk-1) compared to Israeli men (2,205 METs-min*wk-1 p < 0.0001), or to Palestinian and Israeli women, who had similar medians (2776 METs-min*wk-1). Two thirds (65%) of the total MVPA reported by Palestinian women were derived from domestic chores compared to 36% in Israeli women and 25% among Palestinian and Israeli men. A high proportion (63%) of Palestinian men met the PA recommendations by occupation/domestic activity, compared to 39% of Palestinian women and 37% of the Israelis. No leisure time PA was reported by 42% and 39% of Palestinian and Israeli men (p = 0.337) and 53% and 28% of Palestinian and Israeli women (p < 0.0001). Palestinian women reported the lowest level of walking. Considering all domains, 26% of Palestinian women were classified as insufficiently active versus 13% of Palestinian men (p < 0.0001) who did not differ from the Israeli sample (14%). Middle-aged and elderly and less educated Palestinian women, and unemployed and pensioned Palestinian men were at particularly high risk of inactivity. Socio-economic indicators only partially explained the ethnic disparity. Conclusions Substantial proportions of Palestinian women, and subgroups of Palestinian men, are insufficiently active. Culturally appropriate intervention strategies are warranted, particularly for this vulnerable population. PMID:22289260

Lifestyle physical activity among urban Palestinians and Israelis: a cross-sectional comparison in the Palestinian-Israeli Jerusalem risk factor study.

PubMed

Merom, Dafna; Sinnreich, Ronit; Aboudi, Vartohi; Kark, Jeremy D; Nassar, Hisham

2012-01-30

Urban Palestinians have a high incidence of coronary heart disease, and alarming prevalences of obesity (particularly among women) and diabetes. An active lifestyle can help prevent these conditions. Little is known about the physical activity (PA) behavior of Palestinians. This study aimed to determine the prevalence of insufficient PA and its socio-demographic correlates among urban Palestinians in comparison with Israelis. An age-sex stratified random sample of Palestinians and Israelis aged 25-74 years living in east and west Jerusalem was drawn from the Israel National Population Registry: 970 Palestinians and 712 Israelis participated. PA in a typical week was assessed by the Multi-Ethnic Study of Atherosclerosis (MESA) questionnaire. Energy expenditure (EE), calculated in metabolic equivalents (METs), was compared between groups for moderate to vigorous-intensity physical activity (MVPA), using the Wilcoxon rank-sum test, and for domain-specific prevalence rates of meeting public health guidelines and all-domain insufficient PA. Correlates of insufficient PA were assessed by multivariable logistic modeling. Palestinian men had the highest median of MVPA (4740 METs-min*wk-1) compared to Israeli men (2,205 METs-min*wk-1 p < 0.0001), or to Palestinian and Israeli women, who had similar medians (2776 METs-min*wk-1). Two thirds (65%) of the total MVPA reported by Palestinian women were derived from domestic chores compared to 36% in Israeli women and 25% among Palestinian and Israeli men. A high proportion (63%) of Palestinian men met the PA recommendations by occupation/domestic activity, compared to 39% of Palestinian women and 37% of the Israelis. No leisure time PA was reported by 42% and 39% of Palestinian and Israeli men (p = 0.337) and 53% and 28% of Palestinian and Israeli women (p < 0.0001). Palestinian women reported the lowest level of walking. Considering all domains, 26% of Palestinian women were classified as insufficiently active versus 13% of Palestinian men (p < 0.0001) who did not differ from the Israeli sample (14%). Middle-aged and elderly and less educated Palestinian women, and unemployed and pensioned Palestinian men were at particularly high risk of inactivity. Socio-economic indicators only partially explained the ethnic disparity. Substantial proportions of Palestinian women, and subgroups of Palestinian men, are insufficiently active. Culturally appropriate intervention strategies are warranted, particularly for this vulnerable population.

Evaluation of Preanalytical Quality Indicators by Six Sigma and Pareto`s Principle.

PubMed

Kulkarni, Sweta; Ramesh, R; Srinivasan, A R; Silvia, C R Wilma Delphine

2018-01-01

Preanalytical steps are the major sources of error in clinical laboratory. The analytical errors can be corrected by quality control procedures but there is a need for stringent quality checks in preanalytical area as these processes are done outside the laboratory. Sigma value depicts the performance of laboratory and its quality measures. Hence in the present study six sigma and Pareto principle was applied to preanalytical quality indicators to evaluate the clinical biochemistry laboratory performance. This observational study was carried out for a period of 1 year from November 2015-2016. A total of 1,44,208 samples and 54,265 test requisition forms were screened for preanalytical errors like missing patient information, sample collection details in forms and hemolysed, lipemic, inappropriate, insufficient samples and total number of errors were calculated and converted into defects per million and sigma scale. Pareto`s chart was drawn using total number of errors and cumulative percentage. In 75% test requisition forms diagnosis was not mentioned and sigma value of 0.9 was obtained and for other errors like sample receiving time, stat and type of sample sigma values were 2.9, 2.6, and 2.8 respectively. For insufficient sample and improper ratio of blood to anticoagulant sigma value was 4.3. Pareto`s chart depicts out of 80% of errors in requisition forms, 20% is contributed by missing information like diagnosis. The development of quality indicators, application of six sigma and Pareto`s principle are quality measures by which not only preanalytical, the total testing process can be improved.

Thickened Endometrium in Postmenopausal Women With an Initial Biopsy of Limited, Benign, Surface Endometrium: Clinical Outcome and Subsequent Pathologic Diagnosis.

PubMed

Dermawan, Josephine K T; Hur, Christine; Uberti, Maria G; Flyckt, Rebecca; Falcone, Tommaso; Brainard, Jennifer; Abdul-Karim, Fadi W

2018-05-10

Endometrial biopsy or curetting is indicated for postmenopausal women with abnormal uterine bleeding and/or thickened endometrium. Often, endometrial biopsy or curetting yields limited benign surface endometrium, which may indicate insufficient sampling. This study addresses the clinical outcome and subsequent pathologic diagnoses in postmenopausal women who received this initial diagnosis. Among a total of 370 endometrial biopsy or curetting between 2012 and 2015, 192 (52%) were diagnosed as limited benign surface endometrial epithelium. The women ranged in age from 55 to 91 yr old. Their clinical presentations mainly included postmenopausal bleeding, pelvic pain, and enlarged uterus. Primarily because the initial report was interpreted as "benign," 108 (57%) had no subsequent follow-up. Interestingly, women with an increased endometrial thickness were more likely to receive repeat evaluation. Among the 84 women who underwent follow-up endometrial sampling, 6 (7%) had hyperplasia with atypia or malignancy, 21 (25%) had a repeat diagnosis of limited surface sample, 4 (5%) had insufficient materials, and 53 (63%) had other benign findings. Among the subset of women who did receive subsequent follow-up, endometrial atypia or malignancies are more likely found in those with increased body mass index. In conclusion, a slight majority of women with postmenopausal bleeding and/or thickened endometrium had an initial limited surface endometrial sample. Most had no subsequent endometrial sampling. Among those with subsequent follow-up, the majority had benign findings. The study highlights the inconsistencies in adequacy criteria for endometrial sampling and the lack of standardization of subsequent management.

A work-life perspective on sleep and fatigue--looking beyond shift workers.

PubMed

Skinner, Natalie; Dorrian, Jill

2015-01-01

This study examines sleep and fatigue through a work-life lens. Whilst most often thought of as an issue for shift workers, this study observed that self-reported insufficient sleep and fatigue were prevalent for workers on standard daytime schedules. Using a representative sample of 573 daytime workers (51.3% men; 70.7% aged 25-54 yr) from one Australian state, it was observed that 26.4% of daytime workers never or rarely get the seven hours of sleep a night that is recommended for good health. Those with parenting responsibilites (29.4%) or working long (45+) hours (37.4%) were most likely to report insufficient sleep. Whereas mothers in full-time work were most likely to report frequent fatigue (42.5%). This study highlights the common experience of insufficient sleep and fatigue in a daytime workforce, with significant implications for health and safety at work and outside of work. Stronger and more effective legislation addressing safe and 'decent' working time is clearly needed, along with greater awareness and acceptance within workplace cultures of the need to support reasonable workloads and working hours.

Allostasis and Allostatic Load in the Context of Poverty in Early Childhood

PubMed Central

Blair, Clancy; Raver, Cybele; Granger, Douglas; Mills-Koonce, Roger; Hibel, Leah

2014-01-01

This paper examined the relation of early environmental adversity associated with poverty to child resting or basal level of cortisol in a prospective longitudinal sample of 1,135 children seen at 7, 15, 24, 35, and 48 months of age. We found main effects for length of time in poverty, poor housing quality, African American ethnicity, and low positive caregiving behavior in which each was uniquely associated with an overall higher level of cortisol from age 7 months to 48 months. We also found that two aspects of the early environment in the context of poverty, adult exits from the home and perceived economic insufficiency, were related to salivary cortisol in a time dependent manner. The effect for the first of these, exits from the home, was consistent with the principle of allostatic load in which the effects of adversity on stress physiology accumulate over time. The effect for perceived economic insufficiency was one in which insufficiency was associated with higher levels of cortisol in infancy but with a typical but steeper decline in cortisol with age at subsequent time points. PMID:21756436

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.

The Context of Military Environments: An Agenda for Basic Research on Social and Organizational Factors Relevant to Small Units

DTIC Science & Technology

2014-06-01

Agenda for Basic Research on Social and Organizational Factors Relevant to Small Units NORMS IN MILITARY ENVIRONMENTS 25 group members regardless of...Army personnel. FUTURE RESEARCH ON NORMS With a scientifically informed understanding of social norms, the roles they play in individual and group ...world, and insufficient research has been conducted on similar groups (with respect to size, responsibility, mission, etc.) to be of much utility to

[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.

Risk factors of acute myocardial infarction in middle-aged and adolescent people (< 45 years) in Yantai.

PubMed

Du, Hong; Dong, Chang-Yan; Lin, Qiao-Yan

2015-09-29

Yantai is a developed medium-sized coastal city in Eastern China, having a population of 1.6845 million. With the development of economy, some middle-aged and adolescent people (< 45 years) devote themselves to work and suffer from greater stress, which makes them ignore their own health. Moreover, they have unhealthy lifestyles and lack the knowledge of cardiovascular risk factors. To identify the risk factors for first acute myocardial infarction in middle-aged and adolescent people in Yantai, a developed medium-sized coastal city in Eastern China. A total of 154 consecutive patients with first acute myocardial infarction (< 45 years), were enrolled in case group, and 462 patients without myocardial infarction were enrolled in control group. Three controls with the same sex and age were matched to each case. The risk factors were identified with univariate and multivariate analysis. Unhealthy food habit (eating seafood and meanwhile drinking beer), hypertension, current smokers, self-perceived stress, diabetes mellitus, obesity, sleep insufficience, hypercholesterolaemia and fatigue were independent risk factors for first acute myocardial infarction (P < 0.05). Besides those recognized risk factors for cardiovascular disease (hypertension, hypercholesterolemia, diabetes mellitus and smoking), eating seafood and meanwhile drinking beer, self-perceived stress, sleep insufficience, obesity and fatigue were also the risk factors for first acute myocardial infarction in middle-aged and adolescent people in Yantai.

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…

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…

Serum 25-hydroxyvitamin D levels in vitamin D-insufficient hip fracture patients after supplementation with ergocalciferol and cholecalciferol.

PubMed

Glendenning, Paul; Chew, Gerard T; Seymour, Hannah M; Gillett, Melissa J; Goldswain, Peter R; Inderjeeth, Charles A; Vasikaran, Samuel D; Taranto, Mario; Musk, Alexander A; Fraser, William D

2009-11-01

Vitamin D insufficiency is commonly associated with hip fracture. However, the equipotency of ergocalciferol and cholecalciferol supplementation in this patient group has not been studied in a randomized trial using high-performance liquid chromatography (HPLC) measurement of serum 25-hydroxyvitamin D (25OHD). The objective of this study was to determine if ergocalciferol and cholecalciferol are equipotent therapies in vitamin D-insufficient hip fracture patients. Ninety five hip fracture inpatients with vitamin D insufficiency (25OHD<50 nmol/L) were randomized, double-blind, to treatment with ergocalciferol 1000 IU/day (n=48) or cholecalciferol 1000 IU/day (n=47) for three months. All participants were also given a placebo matching the alternative treatment to maintain blinding of treatment allocation. The primary endpoint was total serum 25OHD measured by HPLC. Secondary endpoints included 25OHD measured by radioimmunoassay (RIA), intact parathyroid hormone (iPTH), and bioactive (1-84) whole PTH (wPTH). Seventy patients (74%) completed the study with paired samples for analysis. Cholecalciferol supplementation resulted in a 31% greater increase in total HPLC-measured 25OHD (p=0.010) and 52% greater rise in RIA-measured 25OHD (p<0.001) than supplementation with an equivalent dose of ergocalciferol. Changes in iPTH and wPTH were not significantly different between calciferol treatments (p>0.05). In vitamin D-insufficient hip fracture patients, supplementation with cholecalciferol 1000 IU/day for three months was more effective in increasing serum 25OHD than an equivalent dose of ergocalciferol. However, the lack of difference in PTH lowering between calciferol treatments raises questions about the biological importance of this observation.

Curriculum-Based Handwriting Programs: A Systematic Review With Effect Sizes

PubMed Central

Engel, Courtney; Lillie, Kristin; Zurawski, Sarah; Travers, Brittany G.

2018-01-01

Challenges with handwriting can have a negative impact on academic performance, and these challenges are commonly addressed by occupational therapy practitioners in school settings. This systematic review examined the efficacy of curriculum-based interventions to address children’s handwriting difficulties in the classroom (preschool to second grade). We reviewed and computed effect sizes for 13 studies (11 Level II, 2 Level III) identified through a comprehensive database search. The evidence shows that curriculum-based handwriting interventions resulted in small- to medium-sized improvements in legibility, a commonly reported challenge in this age group. The evidence for whether these interventions improved speed is mixed, and the evidence for whether they improved fluency is insufficient. No clear support was found for one handwriting program over another. These results suggest that curriculum-based interventions can lead to improvements in handwriting legibility, but Level I research is needed to validate the efficacy of these curricula. PMID:29689170

Right-sided infective endocarditis: recent epidemiologic changes

PubMed Central

Yuan, Shi-Min

2014-01-01

Background: Infective endocarditis (IE) has been increasingly reported, however, little is available regarding recent development of right-sided IE. Methods: Right-sided IE was comprehensively analyzed based on recent 5⅓-year literature. Results: Portal of entry, implanted foreign material, and repaired congenital heart defects were the main predisposing risk factors. Vegetation size on the right-sided valves was much smaller than those beyond the valves. Multiple logistic regression analysis revealed that predisposing risk factors, and vegetation size and locations were independent predictive risks of patients’ survival. Conclusions: Changes of right-sided IE in the past 5⅓ years included younger patient age, and increased vegetation size, but still prominent Staphylococcus aureus infections. Complication spectrum has changed into more valve insufficiency, more embolic events, reduced abscess formation, and considerably decreased valve perforations. With effective antibiotic regimens, prognoses of the patients seemed to be better than before. PMID:24482708

Critical size of ego communication networks

NASA Astrophysics Data System (ADS)

Wang, Qing; Gao, Jian; Zhou, Tao; Hu, Zheng; Tian, Hui

2016-06-01

With the help of information and communication technologies, studies on the overall social networks have been extensively reported recently. However, investigations on the directed Ego Communication Networks (ECNs) remain insufficient, where an ECN stands for a sub network composed of a centralized individual and his/her direct contacts. In this paper, the directed ECNs are built on the Call Detail Records (CDRs), which cover more than 7 million people of a provincial capital city in China for half a year. Results show that there is a critical size for ECN at about 150, above which the average emotional closeness between ego and alters drops, the balanced relationship between ego and network collapses, and the proportion of strong ties decreases. This paper not only demonstrate the significance of ECN size in affecting its properties, but also shows accordance with the “Dunbar's Number”. These results can be viewed as a cross-culture supportive evidence to the well-known Social Brain Hypothesis (SBH).

Graft downsizing during ex vivo lung perfusion: case report and technical notes.

PubMed

Nosotti, M; Rosso, L; Mendogni, P; Tosi, D; Palleschi, A; Righi, I; Froio, S; Valenza, F; Santambrogio, L

2014-09-01

Among patients with respiratory insufficiency awaiting lung transplantation, small adult patients have a lower opportunity of receiving size-matched pulmonary grafts, because of the shortage of donors, particularly those of small size. Reducing the size of an oversized graft is one of the methods to increase the donor pool; similarly, ex vivo lung perfusion is an emerging technique aimed toward the same purpose. We describe how we combined the 2 techniques (lobar transplantation plus contralateral nonanatomic graft reduction during ex vivo lung perfusion) to overcome graft shortage in a clinical case. For the 1st time, this case report demonstrates that surgical manipulation during ex vivo lung perfusion does not affect the functional improvement in a lung previously judged to be not suitable for transplantation. The 6-month follow-up results are similar to those of standard bilateral lung transplantation. Copyright © 2014 Elsevier Inc. All rights reserved.

Addressing Institutional Amplifiers in the Dynamics and Control of Tuberculosis Epidemics

PubMed Central

Basu, Sanjay; Stuckler, David; McKee, Martin

2011-01-01

Tuberculosis outbreaks originating in prisons, mines, or hospital wards can spread to the larger community. Recent proposals have targeted these high-transmission institutional amplifiers by improving case detection, treatment, or reducing the size of the exposed population. However, what effects these alternative proposals may have is unclear. We mathematically modeled these control strategies and found case detection and treatment methods insufficient in addressing epidemics involving common types of institutional amplifiers. Movement of persons in and out of amplifiers fundamentally altered the transmission dynamics of tuberculosis in a manner not effectively mitigated by detection or treatment alone. Policies increasing the population size exposed to amplifiers or the per-person duration of exposure within amplifiers potentially worsened incidence, even in settings with high rates of detection and treatment success. However, reducing the total population size entering institutional amplifiers significantly lowered tuberculosis incidence and the risk of propagating new drug-resistant tuberculosis strains. PMID:21212197

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.

Laboratory Experiments Lead to a New Understanding of Wildland Fire Spread

NASA Astrophysics Data System (ADS)

Cohen, J. D.; Finney, M.; McAllister, S.

2015-12-01

Wildfire flame spread results from a sequence of ignitions where adjacent fuel particles heat from radiation and convection leading to their ignition. Surprisingly, after decades of fire behavior research an experimentally based, fundamental understanding of wildland fire spread processes has not been established. Modelers have commonly assumed radiation to be the dominant heating mechanism; that is, radiation heat transfer primarily determines wildland fire spread. We tested this assumption by focusing on how fuel ignition occurs with a renewed emphasis on experimental research. Our experiments show that fuel particle size can non-linearly influence a fuel particle's convective heat transfer. Fine fuels (less than 1 mm) can convectively cool in ambient air such that radiation heating is insufficient for ignition and thus fire spread. Given fire spread with insufficient radiant heating, fuel particle ignition must occur convectively from flame contact. Further experimentation reveals that convective heating and particle ignition occur when buoyancy-induced instabilities and vorticity force flames down and forward to produce intermittent contact with the adjacent fuel bed. Experimental results suggest these intermittent forward flame extensions are buoyancy driven with predictable average frequencies for flame zones ranging from laboratory (10-2 m) to field scales (101m). Measured fuel particle temperatures and boundary conditions during spreading laboratory fires reveal that convection heat transfer from intermittent flame contact is the principal mechanism responsible for heating fine fuel particles to ignition. Our experimental results describe how fine fuel particles convectively heat to ignition from flame contact related to the buoyant dynamics of spreading flame fronts. This research has caused a rethinking of some of the most basic concepts in wildland fuel particle ignition and flame spread.

Are pushing and pulling work-related risk factors for upper extremity symptoms? A systematic review of observational studies.

PubMed

Hoozemans, M J M; Knelange, E B; Frings-Dresen, M H W; Veeger, H E J; Kuijer, P P F M

2014-11-01

Systematically review observational studies concerning the question whether workers that perform pushing/pulling activities have an increased risk for upper extremity symptoms as compared to workers that perform no pushing/pulling activities. A search in MEDLINE via PubMed and EMBASE was performed with work-related search terms combined with push/pushing/pull/pulling. Studies had to examine exposure to pushing/pulling in relation to upper extremity symptoms. Two authors performed the literature selection and assessment of the risk of bias in the studies independently. A best evidence synthesis was used to draw conclusions in terms of strong, moderate or conflicting/insufficient evidence. The search resulted in 4764 studies. Seven studies were included, with three of them of low risk of bias, in total including 8279 participants. A positive significant relationship with upper extremity symptoms was observed in all four prospective cohort studies with effect sizes varying between 1.5 and 4.9. Two out of the three remaining studies also reported a positive association with upper extremity symptoms. In addition, significant positive associations with neck/shoulder symptoms were found in two prospective cohort studies with effect sizes of 1.5 and 1.6, and with shoulder symptoms in one of two cross-sectional studies with an effect size of 2.1. There is strong evidence that pushing/pulling is related to upper extremity symptoms, specifically for shoulder symptoms. There is insufficient or conflicting evidence that pushing/pulling is related to (combinations of) upper arm, elbow, forearm, wrist or hand symptoms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Geomorphology and Geology of the Southwestern Margaritifer Sinus and Argyre Regions of Mars. Part 4: Flow Ejecta Crater Distribution

NASA Technical Reports Server (NTRS)

Parker, T. J.; Pieri, D. C.

1985-01-01

Flow ejecta craters - craters surrounded by lobate ejecta blankets - are found throughout the study area. The ratio of the crater's diameter to that of the flow ejecta in this region is approximately 40 to 45%. Flow ejecta craters are dominantly sharply defined craters, with slightly degraded craters being somewhat less common. This is probably indicative of the ejecta's relatively low resistence to weathering and susceptibility to burial. Flow ejecta craters here seem to occur within a narrow range of crater sizes - the smallest being about 4km in diameter and the largest being about 27km in diameter. Ejecta blankets of craters at 4km are easily seen and those of smaller craters are simply not seen even in images with better than average resolution for the region. This may be due to the depth of excavation of small impacting bodies being insufficient to reach volatile-rich material. Flow ejecta craters above 24km are rare, and those craters above 27km do not display flow ejecta blankets. This may be a result of an excavation depth so great that the volatile content of the ejecta is insufficient to form a fluid ejecta blanket. The geomorphic/geologic unit appears also to play an important role in the formation of flow ejecta craters. Given the typical size range for the occurrence of flow ejecta craters for most units, it can be seen that the percentage of flow ejecta craters to the total number of craters within this size range varies significantly from one unit to the next. The wide variance in flow ejecta crater density over this relatively small geographical area argues strongly for a lithologic control of their distribution.

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.

Reconnaissance of Stream Geomorphology, Low Streamflow, and Stream Temperature in the Mountaintop Coal-Mining Region, Southern West Virginia, 1999-2000

USGS Publications Warehouse

Wiley, Jeffrey B.; Evaldi, Ronald D.; Eychaner, James H.; Chambers, Douglas B.

2001-01-01

The effects of mountaintop removal coal mining and the valley fills created by this mining method in southern West Virginia were investigated by comparing data collected at valley-fill, mined, and unmined sites. Bed material downstream of valley-fill sites had a greater number of particles less than 2 millimeters and a smaller median particle size than the mined and unmined sites. At the 84th percentile of sampled data, however, bed material at each site type had about the same size particles. Bankfull cross-sectional areas at a riffle section were approximately equal at valley-fill and unmined sites, but not enough time has passed and insufficient streamflows since the land was disturbed may have prevented the stream channel at valley-fill sites from reaching equilibrium. The 90-percent flow durations at valley-fill sites generally were 6-7 times greater than at unmined sites. Some valley-fill sites, however, exhibited streamflows similar to unmined sites, and some unmined sites exhibited streamflows similar to valley-fill sites. Daily streamflows from valley-fill sites generally are greater than daily streamflows from unmined sites during periods of low streamflow. Valley-fill sites have a greater percentage of base-flow and a lower percentage of flow from storm runoff than unmined sites. Water temperatures from a valley-fill site exhibited lower daily fluctuations and seasonal variations than water temperatures from an unmined site.

Determinants of birth interval in a rural Mediterranean population (La Alpujarra, Spain).

PubMed

Polo, V; Luna, F; Fuster, V

2000-10-01

The fertility pattern, in terms of birth intervals, in a rural population not practicing contraception belonging to La Alta Alpujarra Oriental (southeast Spain) is analyzed. During the first half of the 20th century, this population experienced a considerable degree of geographical and cultural isolation. Because of this population's high variability in fertility and therefore in birth intervals, the analysis was limited to a homogenous subsample of 154 families, each with at least five pregnancies. This limitation allowed us to analyze, among and within families, effects of a set of variables on the interbirth pattern, and to avoid possible problems of pseudoreplication. Information on birth date of the mother, age at marriage, children's birth date and death date, birth order, and frequency of miscarriages was collected. Our results indicate that interbirth intervals depend on an exponential effect of maternal age, especially significant after the age of 35. This effect is probably related to the biological degenerative processes of female fertility with age. A linear increase of birth intervals with birth order within families was found as well as a reduction of intervals among families experiencing an infant death. Our sample size was insufficient to detect a possible replacement behavior in the case of infant death. High natality and mortality rates, a secular decrease of natality rates, a log-normal birth interval, and family-size distributions suggest that La Alpujarra has been a natural fertility population following a demographic transition process.

Systematic evaluation of deep learning based detection frameworks for aerial imagery

NASA Astrophysics Data System (ADS)

Sommer, Lars; Steinmann, Lucas; Schumann, Arne; Beyerer, Jürgen

2018-04-01

Object detection in aerial imagery is crucial for many applications in the civil and military domain. In recent years, deep learning based object detection frameworks significantly outperformed conventional approaches based on hand-crafted features on several datasets. However, these detection frameworks are generally designed and optimized for common benchmark datasets, which considerably differ from aerial imagery especially in object sizes. As already demonstrated for Faster R-CNN, several adaptations are necessary to account for these differences. In this work, we adapt several state-of-the-art detection frameworks including Faster R-CNN, R-FCN, and Single Shot MultiBox Detector (SSD) to aerial imagery. We discuss adaptations that mainly improve the detection accuracy of all frameworks in detail. As the output of deeper convolutional layers comprise more semantic information, these layers are generally used in detection frameworks as feature map to locate and classify objects. However, the resolution of these feature maps is insufficient for handling small object instances, which results in an inaccurate localization or incorrect classification of small objects. Furthermore, state-of-the-art detection frameworks perform bounding box regression to predict the exact object location. Therefore, so called anchor or default boxes are used as reference. We demonstrate how an appropriate choice of anchor box sizes can considerably improve detection performance. Furthermore, we evaluate the impact of the performed adaptations on two publicly available datasets to account for various ground sampling distances or differing backgrounds. The presented adaptations can be used as guideline for further datasets or detection frameworks.

Discrete wavelet-aided delineation of PCG signal events via analysis of an area curve length-based decision statistic.

PubMed

Homaeinezhad, M R; Atyabi, S A; Daneshvar, E; Ghaffari, A; Tahmasebi, M

2010-12-01

The aim of this study is to describe a robust unified framework for segmentation of the phonocardiogram (PCG) signal sounds based on the false-alarm probability (FAP) bounded segmentation of a properly calculated detection measure. To this end, first the original PCG signal is appropriately pre-processed and then, a fixed sample size sliding window is moved on the pre-processed signal. In each slid, the area under the excerpted segment is multiplied by its curve-length to generate the Area Curve Length (ACL) metric to be used as the segmentation decision statistic (DS). Afterwards, histogram parameters of the nonlinearly enhanced DS metric are used for regulation of the α-level Neyman-Pearson classifier for FAP-bounded delineation of the PCG events. The proposed method was applied to all 85 records of Nursing Student Heart Sounds database (NSHSDB) including stenosis, insufficiency, regurgitation, gallop, septal defect, split sound, rumble, murmur, clicks, friction rub and snap disorders with different sampling frequencies. Also, the method was applied to the records obtained from an electronic stethoscope board designed for fulfillment of this study in the presence of high-level power-line noise and external disturbing sounds and as the results, no false positive (FP) or false negative (FN) errors were detected. High noise robustness, acceptable detection-segmentation accuracy of PCG events in various cardiac system conditions, and having no parameters dependency to the acquisition sampling frequency can be mentioned as the principal virtues and abilities of the proposed ACL-based PCG events detection-segmentation algorithm.

Analyzing small data sets using Bayesian estimation: the case of posttraumatic stress symptoms following mechanical ventilation in burn survivors

PubMed Central

van de Schoot, Rens; Broere, Joris J.; Perryck, Koen H.; Zondervan-Zwijnenburg, Mariëlle; van Loey, Nancy E.

2015-01-01

Background The analysis of small data sets in longitudinal studies can lead to power issues and often suffers from biased parameter values. These issues can be solved by using Bayesian estimation in conjunction with informative prior distributions. By means of a simulation study and an empirical example concerning posttraumatic stress symptoms (PTSS) following mechanical ventilation in burn survivors, we demonstrate the advantages and potential pitfalls of using Bayesian estimation. Methods First, we show how to specify prior distributions and by means of a sensitivity analysis we demonstrate how to check the exact influence of the prior (mis-) specification. Thereafter, we show by means of a simulation the situations in which the Bayesian approach outperforms the default, maximum likelihood and approach. Finally, we re-analyze empirical data on burn survivors which provided preliminary evidence of an aversive influence of a period of mechanical ventilation on the course of PTSS following burns. Results Not suprisingly, maximum likelihood estimation showed insufficient coverage as well as power with very small samples. Only when Bayesian analysis, in conjunction with informative priors, was used power increased to acceptable levels. As expected, we showed that the smaller the sample size the more the results rely on the prior specification. Conclusion We show that two issues often encountered during analysis of small samples, power and biased parameters, can be solved by including prior information into Bayesian analysis. We argue that the use of informative priors should always be reported together with a sensitivity analysis. PMID:25765534

Analyzing small data sets using Bayesian estimation: the case of posttraumatic stress symptoms following mechanical ventilation in burn survivors.

PubMed

van de Schoot, Rens; Broere, Joris J; Perryck, Koen H; Zondervan-Zwijnenburg, Mariëlle; van Loey, Nancy E

2015-01-01

Background : The analysis of small data sets in longitudinal studies can lead to power issues and often suffers from biased parameter values. These issues can be solved by using Bayesian estimation in conjunction with informative prior distributions. By means of a simulation study and an empirical example concerning posttraumatic stress symptoms (PTSS) following mechanical ventilation in burn survivors, we demonstrate the advantages and potential pitfalls of using Bayesian estimation. Methods : First, we show how to specify prior distributions and by means of a sensitivity analysis we demonstrate how to check the exact influence of the prior (mis-) specification. Thereafter, we show by means of a simulation the situations in which the Bayesian approach outperforms the default, maximum likelihood and approach. Finally, we re-analyze empirical data on burn survivors which provided preliminary evidence of an aversive influence of a period of mechanical ventilation on the course of PTSS following burns. Results : Not suprisingly, maximum likelihood estimation showed insufficient coverage as well as power with very small samples. Only when Bayesian analysis, in conjunction with informative priors, was used power increased to acceptable levels. As expected, we showed that the smaller the sample size the more the results rely on the prior specification. Conclusion : We show that two issues often encountered during analysis of small samples, power and biased parameters, can be solved by including prior information into Bayesian analysis. We argue that the use of informative priors should always be reported together with a sensitivity analysis.

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.

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.

Hamstring autograft size importance in anterior cruciate ligament repair surgery.

PubMed

Figueroa, Francisco; Figueroa, David; Espregueira-Mendes, João

2018-03-01

Graft size in hamstring autograft anterior cruciate ligament (ACL) surgery is an important factor directly related to failure. Most of the evidence in the field suggests that the size of the graft in hamstring autograft ACL reconstruction matters when the surgeon is trying to avoid failures.The exact graft diameter needed to avoid failures is not absolutely clear and could depend on other factors, but newer studies suggest than even increases of 0.5 mm up to a graft size of 10 mm are beneficial for the patient. There is still no evidence to recommend the use of grafts > 10 mm.Several methods - e.g. folding the graft in more strands - that are simple and reproducible have been published lately to address the problem of having an insufficient graft size when performing an ACL reconstruction. Due to the evidence presented, we think it is necessary for the surgeon to have them in his or her arsenal before performing an ACL reconstruction.There are obviously other factors that should be considered, especially age. Therefore, a larger graft size should not be taken as the only goal in ACL reconstruction. Cite this article: EFORT Open Rev 2018;3:93-97. DOI: 10.1302/2058-5241.3.170038.

Size Distributions of Solar Proton Events: Methodological and Physical Restrictions

NASA Astrophysics Data System (ADS)

Miroshnichenko, L. I.; Yanke, V. G.

2016-12-01

Based on the new catalogue of solar proton events (SPEs) for the period of 1997 - 2009 (Solar Cycle 23) we revisit the long-studied problem of the event-size distributions in the context of those constructed for other solar-flare parameters. Recent results on the problem of size distributions of solar flares and proton events are briefly reviewed. Even a cursory acquaintance with this research field reveals a rather mixed and controversial picture. We concentrate on three main issues: i) SPE size distribution for {>} 10 MeV protons in Solar Cycle 23; ii) size distribution of {>} 1 GV proton events in 1942 - 2014; iii) variations of annual numbers for {>} 10 MeV proton events on long time scales (1955 - 2015). Different results are critically compared; most of the studies in this field are shown to suffer from vastly different input datasets as well as from insufficient knowledge of underlying physical processes in the SPEs under consideration. New studies in this field should be made on more distinct physical and methodological bases. It is important to note the evident similarity in size distributions of solar flares and superflares in Sun-like stars.

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.

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.

Trial Sequential Analysis in systematic reviews with meta-analysis.

PubMed

Wetterslev, Jørn; Jakobsen, Janus Christian; Gluud, Christian

2017-03-06

Most meta-analyses in systematic reviews, including Cochrane ones, do not have sufficient statistical power to detect or refute even large intervention effects. This is why a meta-analysis ought to be regarded as an interim analysis on its way towards a required information size. The results of the meta-analyses should relate the total number of randomised participants to the estimated required meta-analytic information size accounting for statistical diversity. When the number of participants and the corresponding number of trials in a meta-analysis are insufficient, the use of the traditional 95% confidence interval or the 5% statistical significance threshold will lead to too many false positive conclusions (type I errors) and too many false negative conclusions (type II errors). We developed a methodology for interpreting meta-analysis results, using generally accepted, valid evidence on how to adjust thresholds for significance in randomised clinical trials when the required sample size has not been reached. The Lan-DeMets trial sequential monitoring boundaries in Trial Sequential Analysis offer adjusted confidence intervals and restricted thresholds for statistical significance when the diversity-adjusted required information size and the corresponding number of required trials for the meta-analysis have not been reached. Trial Sequential Analysis provides a frequentistic approach to control both type I and type II errors. We define the required information size and the corresponding number of required trials in a meta-analysis and the diversity (D 2 ) measure of heterogeneity. We explain the reasons for using Trial Sequential Analysis of meta-analysis when the actual information size fails to reach the required information size. We present examples drawn from traditional meta-analyses using unadjusted naïve 95% confidence intervals and 5% thresholds for statistical significance. Spurious conclusions in systematic reviews with traditional meta-analyses can be reduced using Trial Sequential Analysis. Several empirical studies have demonstrated that the Trial Sequential Analysis provides better control of type I errors and of type II errors than the traditional naïve meta-analysis. Trial Sequential Analysis represents analysis of meta-analytic data, with transparent assumptions, and better control of type I and type II errors than the traditional meta-analysis using naïve unadjusted confidence intervals.

Towards evidence-based emergency medicine: best BETs from the Manchester Royal Infirmary. BET 4: does size matter? Chest drains in haemothorax following trauma.

PubMed

2013-11-01

A short-cut review was carried out to establish whether the size of chest drain inserted is important in haemothoraces. Forty-nine papers were found of which four presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are shown in table 4. The clinical bottom line is that while the available evidence suggests that small bore drains may be as effective as large bore drains in resolving traumatic haemothoraces without additional complications, there is insufficient evidence currently available to recommend a change to standard practice (ie, large bore drains).

Limitations on analysis of small particles with an electron probe: pollution studies

USGS Publications Warehouse

Heidel, R.H.; Desborough, G.A.

1975-01-01

Recent literature concerning the size and composition of airborne lead particles in automobile exhaust emissions determined by electron microprobe analysis reports 14 distinct lead compounds. Particle sizes reported were from 0.2 ??m to 2 ??m in the diameter. The determination of chemical formulae for compounds requires quantitative elemental data for individual particles. It was also assumed that the lead bearing particles analysed were solid (specifically non porous or non fluffy) compounds which occurred as discrete (non aggregate) particles. Intensity data obtained in the laboratory from the excited volume in a 1 ??m diameter sphere of solid lead chloride indicate insufficient precision and sensitivity to obtain chemical formulae as reported in the literature for exhaust emission products.

Model-based frequency response characterization of a digital-image analysis system for epifluorescence microscopy

NASA Technical Reports Server (NTRS)

Hazra, Rajeeb; Viles, Charles L.; Park, Stephen K.; Reichenbach, Stephen E.; Sieracki, Michael E.

1992-01-01

Consideration is given to a model-based method for estimating the spatial frequency response of a digital-imaging system (e.g., a CCD camera) that is modeled as a linear, shift-invariant image acquisition subsystem that is cascaded with a linear, shift-variant sampling subsystem. The method characterizes the 2D frequency response of the image acquisition subsystem to beyond the Nyquist frequency by accounting explicitly for insufficient sampling and the sample-scene phase. Results for simulated systems and a real CCD-based epifluorescence microscopy system are presented to demonstrate the accuracy of the method.

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.

Adrenocorticotropin-dependent precocious puberty of testicular origin in a boy with X-linked adrenal hypoplasia congenita due to a novel mutation in the DAX1 gene.

PubMed

Domenice, S; Latronico, A C; Brito, V N; Arnhold, I J; Kok, F; Mendonca, B B

2001-09-01

Primary adrenal insufficiency is a rare condition in pediatric age, and its association with precocious sexual development is very uncommon. We report a 2-yr-old Brazilian boy with DAX1 gene mutation whose first clinical manifestation was isosexual gonadotropin-independent precocious puberty. He presented with pubic hair, enlarged penis and testes, and advanced bone age. T levels were elevated, whereas basal and GnRH-stimulated LH levels were compatible with a prepubertal pattern. Chronic GnRH agonist therapy did not reduce T levels, supporting the diagnosis of gonadotropin-independent precocious puberty. Testotoxicosis was ruled out after normal sequencing of exon 11 of the LH receptor gene. At age 3 yr he developed clinical and hormonal features of severe primary adrenal insufficiency. The entire coding region of the DAX1 gene was analyzed through direct sequencing. A nucleotide G insertion between nucleotides 430 and 431 in exon 1, resulting in a novel frameshift mutation and a premature stop codon at position 71 of DAX-1, was identified. Surprisingly, steroid replacement therapy induced a clear decrease in testicular size and T levels to the prepubertal range. These findings suggest that chronic excessive ACTH levels resulting from adrenal insufficiency may stimulate Leydig cells and lead to gonadotropin-independent precocious puberty in some boys with DAX1 gene mutations.

Steroids for surgery during cardiopulmonary bypass in adults: a meta-analysis.

PubMed

Guay, Joanne; Ochroch, E Andrew

2014-02-01

To evaluate the effect of steroid administration on myocardial infarction (MI), stroke, renal insufficiency, death, intensive care (ICU) length of stay (LOS) and hospital LOS of patients undergoing cardiopulmonary bypass (CPB). Meta-analysis of parallel randomized controlled trials. University hospital. A search was conducted in PubMed, EMBASE, MEDLINE(R) and the Cochrane Central Register of Controlled Trials of studies on adults undergoing surgery with CPB who received steroid administration. Effect size (risk ratio or mean difference) for MI, stroke, renal insufficiency, death, ICU LOS, and hospital LOS were evaluated. 48 RCTs published between 1977 and 2012 were retained for analysis. Steroids had no effect on the MI risk ratio (RR) 0.91 (95% confidence interval [CI] 0.63, 1.32); death at 30 days RR 0.84 (0.59, 1.20); stroke RR 0.92 (0.60, 1.42) or renal insufficiency RR 0.83 (0.52, 1.32). Administration of steroids reduced ICU LOS (P = 0.00001; I(2) 87.5%) and hospital LOS (P = 0.03; I(2) 81.1%). Metaregressions showed that duration of steroid administration was correlated with the reduction in ICU LOS (P = 0.0004) and hospital LOS (P < 0.00001). Increasing the duration of steroid administration may reduce ICU and hospital LOS greater than increasing the dose. Copyright © 2014 Elsevier Inc. All rights reserved.

Fragile X-associated primary ovarian insufficiency: evidence for additional genetic contributions to severity.

PubMed

Hunter, Jessica Ezzell; Epstein, Michael P; Tinker, Stuart W; Charen, Krista H; Sherman, Stephanie L

2008-09-01

The fragile X mental retardation gene (FMR1) contains a CGG repeat sequence in its 5' untranslated region that can become unstable and expand in length from generation to generation. Alleles with expanded repeats in the range of approximately 55-199, termed premutation alleles, are associated with an increased risk for fragile-X-associated primary ovarian insufficiency (FXPOI). However, not all women who carry the premutation develop FXPOI. To determine if additional genes could explain variability in onset and severity, we used a random-effects Cox proportional hazards model to analyze age at menopause on 680 women from 225 families who have a history of fragile X syndrome and 321 women from 219 families from the general population. We tested for the presence of a residual additive genetic effect after adjustment for FMR1 repeat length, race, smoking, body mass index, and method of ascertainment. Results showed significant familial aggregation of age at menopause with an estimated additive genetic variance of 0.55-0.96 depending on the parameterization of FMR1 repeat size and definition of age at menopause (P-values ranging between 0.0002 and 0.0027). This is the first study to analyze familial aggregation of FXPOI. This result is important for proper counseling of women who carry FMR1 premutation alleles and for guidance of future studies to identify additional genes that influence ovarian insufficiency. (c) 2008 Wiley-Liss, Inc.

Pearson syndrome: unique endocrine manifestations including neonatal diabetes and adrenal insufficiency.

PubMed

Williams, T B; Daniels, M; Puthenveetil, G; Chang, R; Wang, R Y; Abdenur, J E

2012-05-01

Pearson syndrome is a very rare metabolic disorder that is usually present in infancy with transfusion dependent macrocytic anemia and multiorgan involvement including exocrine pancreas, liver and renal tubular defects. The disease is secondary to a mitochondrial DNA deletion that is variable in size and location. Endocrine abnormalities can develop, but are usually not part of the initial presentation. We report two patients who presented with unusual endocrine manifestations, neonatal diabetes and adrenal insufficiency, who were both later diagnosed with Pearson syndrome. Medical records were reviewed. Confirmatory testing included: mitochondrial DNA deletion testing and sequencing of the breakpoints, muscle biopsy, and bone marrow studies. Case 1 presented with hyperglycemia requiring insulin at birth. She had several episodes of ketoacidosis triggered by stress and labile blood glucose control. Workup for genetic causes of neonatal diabetes was negative. She had transfusion dependent anemia and died at 24 months due to multisystem organ failure. Case 2 presented with adrenal insufficiency and anemia during inturcurrent illness, requiring steroid replacement since 37 months of age. He is currently 4 years old and has mild anemia. Mitochondrial DNA studies confirmed a 4.9 kb deletion in patient 1 and a 5.1 kb deletion in patient 2. The patients reported highlight the importance of considering mitochondrial DNA disorders in patients with early onset endocrine dysfunction, and expand the knowledge about this rare mitochondrial disease. Copyright © 2012 Elsevier Inc. All rights reserved.

A preliminary analysis of the data from experiment 77-13 and final report on glass fining experiments in zero gravity

NASA Technical Reports Server (NTRS)

Wilcox, W. R.; Subramanian, R. S.; Meyyappan, M.; Smith, H. D.; Mattox, D. M.; Partlow, D. P.

1981-01-01

Thermal fining, thermal migration of bubbles under reduced gravity conditions, and data to verify current theoretical models of bubble location and temperatures as a function of time are discussed. A sample, sodium borate glass, was tested during 5 to 6 minutes of zero gravity during rocket flight. The test cell contained a heater strip; thermocouples were in the sample. At present quantitative data are insufficient to confirm results of theoretical calculations.

Insufficiency of the Young’s modulus for illustrating the mechanical behavior of GaN nanowires

NASA Astrophysics Data System (ADS)

Zamani Kouhpanji, Mohammad Reza; Behzadirad, Mahmoud; Feezell, Daniel; Busani, Tito

2018-05-01

We use a non-classical modified couple stress theory including the acceleration gradients (MCST-AG), to precisely demonstrate the size dependency of the mechanical properties of gallium nitride (GaN) nanowires (NWs). The fundamental elastic constants, Young’s modulus and length scales of the GaN NWs were estimated both experimentally, using a novel experimental technique applied to atomic force microscopy, and theoretically, using atomic simulations. The Young’s modulus, static and the dynamic length scales, calculated with the MCST-AG, were found to be 323 GPa, 13 and 14.5 nm, respectively, for GaN NWs from a few nanometers radii to bulk radii. Analyzing the experimental data using the classical continuum theory shows an improvement in the experimental results by introducing smaller error. Using the length scales determined in MCST-AG, we explain the inconsistency of the Young’s moduli reported in recent literature, and we prove the insufficiency of the Young’s modulus for predicting the mechanical behavior of GaN NWs.

Neonatal liver failure and Leigh syndrome possibly due to CoQ-responsive OXPHOS deficiency.

PubMed

Leshinsky-Silver, E; Levine, A; Nissenkorn, A; Barash, V; Perach, M; Buzhaker, E; Shahmurov, M; Polak-Charcon, S; Lev, D; Lerman-Sagie, T

2003-08-01

CoQ transfers electrons from complexes I and II of the mitochondrial respiratory chain to complex III. There are very few reports on human CoQ deficiency. The clinical presentation is usually characterized by: epilepsy, muscle weakness, ataxia, cerebellar atrophy, migraine, myogloblinuria and developmental delay. We describe a patient who presented with neonatal liver and pancreatic insufficiency, tyrosinemia and hyperammonemia and later developed sensorineural hearing loss and Leigh syndrome. Liver biopsy revealed markedly reduced complex I+III and II+III. Addition of CoQ to the liver homogenate restored the activities, suggesting CoQ depletion. Histological staining showed prominent bridging; septal fibrosis and widening of portal spaces with prominent mixed inflammatory infiltrate, associated with interface hepatitis, bile duct proliferation with numerous bile plugs. Electron microscopy revealed a large number of mitochondria, which were altered in shape and size, widened and disordered intercristal spaces. This may be the first case of Leigh syndrome with liver and pancreas insufficiency, possibly caused by CoQ responsive oxphos deficiency.

[A case of legionellesis pneumonia verified by isolation of Legionella pneumophila serogroup 1 from bronchoalveolar lavage fluid treated with levofloxacine and tigecycline].

PubMed

Galstian, G M; Drokov, M Iu; Katrysh, S A; Kliasova, G A; Giliazitdinova, E A; Karpova, T I; Marakusha, B I; Tartakovskiĭ, I S

2011-01-01

A male patient received non-chemotherapeutic drugs which induced deep neutropenia complicated with sepsis, bilateral pneumonia, acute respiratory insufficiency. Artificial pulmonary ventilation was applied. The examination of bronchoalveolar lavage showed the presence of the culture L. pneumophila (serogroup 1) in a concentration 2 x 10(3) CFU/ml. Antibacterial therapy with levofloxacin in a dose 1000 mg/day was conducted. In a week not only L.pneumophila but also Acinetobacter baumanii was isolated from bronchoalveolar lavage. Tigecyclin was added to levofloxacin treatment. Two air cavities were found in the left lung. The treatment reduced the size of these cavities, infiltrative changes in the lungs and respiratory insufficiency regressed. The patient was discharged from hospital This case is the first case in Russia of L.pneumophila isolation from bronchoalveolar lavage. The case is also characterized by use of tigecycline for treatment of combined legionella and akinetobacterial infection and cavities in the lungs in legionella pneumonia.

Insufficiency of the Young's modulus for illustrating the mechanical behavior of GaN nanowires.

PubMed

Kouhpanji, Mohammad Reza Zamani; Behzadirad, Mahmoud; Feezell, Daniel; Busani, Tito

2018-05-18

We use a non-classical modified couple stress theory including the acceleration gradients (MCST-AG), to precisely demonstrate the size dependency of the mechanical properties of gallium nitride (GaN) nanowires (NWs). The fundamental elastic constants, Young's modulus and length scales of the GaN NWs were estimated both experimentally, using a novel experimental technique applied to atomic force microscopy, and theoretically, using atomic simulations. The Young's modulus, static and the dynamic length scales, calculated with the MCST-AG, were found to be 323 GPa, 13 and 14.5 nm, respectively, for GaN NWs from a few nanometers radii to bulk radii. Analyzing the experimental data using the classical continuum theory shows an improvement in the experimental results by introducing smaller error. Using the length scales determined in MCST-AG, we explain the inconsistency of the Young's moduli reported in recent literature, and we prove the insufficiency of the Young's modulus for predicting the mechanical behavior of GaN NWs.

Local extinction and recolonization, species effective population size, and modern human origins.

PubMed

Eller, Elise; Hawks, John; Relethford, John H

2004-10-01

A primary objection from a population genetics perspective to a multiregional model of modern human origins is that the model posits a large census size, whereas genetic data suggest a small effective population size. The relationship between census size and effective size is complex, but arguments based on an island model of migration show that if the effective population size reflects the number of breeding individuals and the effects of population subdivision, then an effective population size of 10,000 is inconsistent with the census size of 500,000 to 1,000,000 that has been suggested by archeological evidence. However, these models have ignored the effects of population extinction and recolonization, which increase the expected variance among demes and reduce the inbreeding effective population size. Using models developed for population extinction and recolonization, we show that a large census size consistent with the multiregional model can be reconciled with an effective population size of 10,000, but genetic variation among demes must be high, reflecting low interdeme migration rates and a colonization process that involves a small number of colonists or kin-structured colonization. Ethnographic and archeological evidence is insufficient to determine whether such demographic conditions existed among Pleistocene human populations, and further work needs to be done. More realistic models that incorporate isolation by distance and heterogeneity in extinction rates and effective deme sizes also need to be developed. However, if true, a process of population extinction and recolonization has interesting implications for human demographic history.

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.

Attributions for Poverty among College Students: The Impact of Service-Learning and Religiosity

ERIC Educational Resources Information Center

Davidson, Theresa C.

2009-01-01

This study examines service-learning participation and religiosity for their effect on structural and individualistic attributions for poverty. Research on these factors is either insufficient or nonexistent. The data for this study come from a random sample of college students in a Southeastern state. Results indicate that participation in a…

Disparity in Physical Activity among Urban Youth: An Ecologically Guided Assessment

ERIC Educational Resources Information Center

Lenhart, Clare M.; Patterson, Freda; Brown, Michael D.; O'Brien, Matthew J.; Nelson, Deborah B.

2014-01-01

Background: Insufficient physical activity among urban youth increases risk of chronic disease.Purpose:This study assessed reported physical activity to determine when disparities in participation emerge and what ecologically guided factors are linked with high activity. Methods:We administered a cross-sectional survey to a diverse sample of 321…

Social Cognition in Individuals at Ultra-High Risk for Psychosis: A Meta-Analysis

PubMed Central

van Donkersgoed, R. J. M.; Wunderink, L.; Nieboer, R.; Aleman, A.; Pijnenborg, G. H. M.

2015-01-01

Objective Treatment in the ultra-high risk stage for a psychotic episode is critical to the course of symptoms. Markers for the development of psychosis have been studied, to optimize the detection of people at risk of psychosis. One possible marker for the transition to psychosis is social cognition. To estimate effect sizes for social cognition based on a quantitative integration of the published evidence, we conducted a meta-analysis of social cognitive performance in people at ultra high risk (UHR). Methods A literature search (1970-July 2015) was performed in PubMed, PsychINFO, Medline, Embase, and ISI Web of Science, using the search terms ‘social cognition’, ‘theory of mind’, ‘emotion recognition’, ‘attributional style’, ‘social knowledge’, ‘social perception’, ‘empathy’, ‘at risk mental state’, ‘clinical high risk’, ‘psychosis prodrome’, and ‘ultra high risk’. The pooled effect size (Cohen’s D) and the effect sizes for each domain of social cognition were calculated. A random effects model with 95% confidence intervals was used. Results Seventeen studies were included in the analysis. The overall significant effect was of medium magnitude (d = 0.52, 95% Cl = 0.38–0.65). No moderator effects were found for age, gender and sample size. Sub-analyses demonstrated that individuals in the UHR phase show significant moderate deficits in affect recognition and affect discrimination in faces as well as in voices and in verbal Theory of Mind (TOM). Due to an insufficient amount of studies, we did not calculate an effect size for attributional bias and social perception/ knowledge. A majority of studies did not find a correlation between social cognition deficits and transition to psychosis, which may suggest that social cognition in general is not a useful marker for the development of psychosis. However some studies suggest the possible predictive value of verbal TOM and the recognition of specific emotions in faces for the transition into psychosis. More research is needed on these subjects. Conclusion The published literature indicates consistent general impairments in social cognition in people in the UHR phase, but only very specific impairments seem to predict transition to psychosis. PMID:26510175

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.

Post-production losses in iodine concentration of salt hamper the control of iodine deficiency disorders: a case study in northern Ethiopia.

PubMed

Shawel, Dawit; Hagos, Seifu; Lachat, Carl K; Kimanya, Martin E; Kolsteren, Patrick

2010-06-01

Iodine is essential for good function of the thyroid, and its deficiency is of public-health importance in Ethiopia. Iodization of salt is an effective and sustainable strategy to prevent and control iodine deficiency in large populations. The effectiveness of salt-iodization programmes depends on the conservation of iodine concentration in salt at various stages of the supply-chain. The overall objective of the study was to assess the loss of iodine in salt from production to consumption and to estimate the proportion of adults, especially pregnant women, at risk of dietary iodine insufficiency. A cross-sectional study was conducted during February-April 2007 in northern Ethiopia. Iodine concentrations of salt samples from producers (n=41), retailers (n=7), and consumers (n=32) were determined using iodiometric titration. A risk assessment was conducted for dietary iodine insufficiency among adults, including pregnant women, using a semi-probabilistic approach. The concentration of iodine in the sampled salts decreased by 57% from the production site to the consumers. The assessment of exposure showed that adults in 63% (n=20) of the households, including 90% (n=29) with pregnant women, were at risk of insufficient iodine intake. A monitoring and evaluation system needs to be established to ensure adequate supply of iodine along the distribution chain. Special attention is needed for the retailers and consumers. At these levels, dissemination of information regarding proper storage and handling of iodized salt is necessary to address the reported loss of iodine from salt.

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

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.

Semi-Supervised Sparse Representation Based Classification for Face Recognition With Insufficient Labeled Samples

NASA Astrophysics Data System (ADS)

Gao, Yuan; Ma, Jiayi; Yuille, Alan L.

2017-05-01

This paper addresses the problem of face recognition when there is only few, or even only a single, labeled examples of the face that we wish to recognize. Moreover, these examples are typically corrupted by nuisance variables, both linear (i.e., additive nuisance variables such as bad lighting, wearing of glasses) and non-linear (i.e., non-additive pixel-wise nuisance variables such as expression changes). The small number of labeled examples means that it is hard to remove these nuisance variables between the training and testing faces to obtain good recognition performance. To address the problem we propose a method called Semi-Supervised Sparse Representation based Classification (S$^3$RC). This is based on recent work on sparsity where faces are represented in terms of two dictionaries: a gallery dictionary consisting of one or more examples of each person, and a variation dictionary representing linear nuisance variables (e.g., different lighting conditions, different glasses). The main idea is that (i) we use the variation dictionary to characterize the linear nuisance variables via the sparsity framework, then (ii) prototype face images are estimated as a gallery dictionary via a Gaussian Mixture Model (GMM), with mixed labeled and unlabeled samples in a semi-supervised manner, to deal with the non-linear nuisance variations between labeled and unlabeled samples. We have done experiments with insufficient labeled samples, even when there is only a single labeled sample per person. Our results on the AR, Multi-PIE, CAS-PEAL, and LFW databases demonstrate that the proposed method is able to deliver significantly improved performance over existing methods.

Vitamin D deficiency at birth among military dependants in Hawai'i.

PubMed

Palmer, Eldon G; Ramirez-Enriquez, Emmanuel; Frioux, Sarah M; Tyree, Melissa M

2013-03-01

Vitamin D has long been known to be essential in bone mineralization as well as calcium and phosphate regulation. An increasing body of literature suggests that Vitamin D is also key in many other areas to include immune function, brain development, prevention of autoimmune disease, and prevention of certain types of cancers. Studies also suggest that, with decreased sun exposure due to concern for skin cancer risk, much of the world's population is becoming increasingly deficient in vitamin D. Our hypothesis was that vitamin D deficiency exists, and can be detected, even in sunny climates such as the state of Hawai'i. To test this hypothesis, eighty-six cord blood samples were collected in the process of routine clinical testing. These samples were tested for 25-hydroxy vitamin D via liquid chromatography mass spectroscopy. Percent deficiency (<20ng/mL) and insufficiency (20-31.9ng/mL) were determined by statistical analysis. Forty-six percent (n=37) of cord blood samples tested were deficient in vitamin D; 47 percent (n=38) of samples had insufficient 25-OH vitamin D. Only 7 percent (n=6) of samples showed vitamin D concentrations at the recommended levels. A vast majority of military dependents in Hawai'i have less than optimal vitamin D levels at birth. Further investigation of vitamin D supplementation during pregnancy is required to optimize vitamin D status at birth. We conclude that a vast majority of military dependents in Hawai'i have less than optimal vitamin D levels at birth supporting the recommendation for supplementation in this population.

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).

Combined effects of fruit and vegetables intake and physical activity on the risk of metabolic syndrome among Chinese adults.

PubMed

Li, Xin-Tong; Liao, Wei; Yu, Hong-Jie; Liu, Ming-Wei; Yuan, Shuai; Tang, Bo-Wen; Yang, Xu-Hao; Song, Yong; Huang, Yao; Cheng, Shi-le; Chen, Zhi-Yu; Towne, Samuel D; Mao, Zong-Fu; He, Qi-Qiang

2017-01-01

Unbalanced dietary intake and insufficient physical activity (PA) have been recognized as risk factors for metabolic syndrome (MetS). We aimed to examine the independent and combined effects of fruit and vegetables (FV) intake and PA on MetS. A cross-sectional survey was conducted among residents of China in 2009, with fasting blood samples collected. Participants were divided into sufficient/insufficient FV intake and adequate/ inadequate PA groups according to self-reported questionnaires. MetS was defined using the NCEP-ATPIII criteria. The difference of individual MetS components was compared across different PA or FV groups. Multivariable logistic regression was used to assess association between FV/PA and the risk of MetS. A total of 7424 adults were included in the current study. MetS was prevalent in 28.7% of participants, with 24.7% and 32.9% in male and female, respectively. Compared with those with inadequate PA and insufficient FV intake, participants with the combination of adequate PA and sufficient FV intake had the lowest risk of MetS (OR = 0.69,95%CI: 0.59-0.82), following by the group with adequate PA time but insufficient FV intake (OR = 0.74, 95%CI:0.65-0.83). Findings of the current study show that the combination of sufficient FV intake and adequate PA was significantly associated with reduced MetS risk among adult residents of China.

Stated Uptake of Physical Activity Rewards Programmes Among Active and Insufficiently Active Full-Time Employees.

PubMed

Ozdemir, Semra; Bilger, Marcel; Finkelstein, Eric A

2017-10-01

Employers are increasingly relying on rewards programmes in an effort to promote greater levels of activity among employees; however, if enrolment in these programmes is dominated by active employees, then they are unlikely to be a good use of resources. This study uses a stated-preference survey to better understand who participates in rewards-based physical activity programmes, and to quantify stated uptake by active and insufficiently active employees. The survey was fielded to a national sample of 950 full-time employees in Singapore between 2012 and 2013. Participants were asked to choose between hypothetical rewards programmes that varied along key dimensions and whether or not they would join their preferred programme if given the opportunity. A mixed logit model was used to analyse the data and estimate predicted uptake for specific programmes. We then simulated employer payments based on predictions for the percentage of each type of employee likely to meet the activity goal. Stated uptake ranged from 31 to 67% of employees, depending on programme features. For each programme, approximately two-thirds of those likely to enrol were insufficiently active. Results showed that insufficiently active employees, who represent the majority, are attracted to rewards-based physical activity programmes, and at approximately the same rate as active employees, even when enrolment fees are required. This suggests that a programme with generous rewards and a modest enrolment fee may have strong employee support and be within the range of what employers may be willing to spend.

Insufficient Sleep and Suicidality in Adolescents

PubMed Central

Lee, Yu Jin; Cho, Seong-Jin; Cho, In Hee; Kim, Seog Ju

2012-01-01

Study Objectives: To investigate the association between the behaviorally induced insufficient sleep and suicidality among adolescents. Design: A population-based, cross-sectional survey. Setting: General community. Participants: A sample of 8,530 students (grades 7-11) was recruited in the Republic of Korea. The participants were 8,010 students who completed all questionnaires. Intervention: N/A. Measurements: The survey included the Beck Scale for Suicidal Ideation (SSI), the Beck Depression Inventory (BDI), a modified Epworth Sleepiness Scale (ESS), and questionnaires about sleep (weekday/weekend sleep schedule/duration, insomnia and snoring). Results: Adolescents with behaviorally induced insufficient sleep syndrome (BISS) had higher SSI scores than those who slept ≥ 7 hours on weekdays, even after controlling for age, sex, and BDI score (F = 11.71, P < 0.001). After controlling for age and sex, longer weekend oversleep and shorter weekday sleep duration predicted a higher SSI score (β = 0.19, P < 0.001; β = 0.37, P < 0.001). The association between weekend oversleep and SSI score remained significant even after additionally controlling for BDI and ESS scores and presence of insomnia and snoring (β = 0.07, P < 0.01). Conclusion: BISS was found to be associated with increased suicidality. Weekend oversleep was associated with suicidality independently of depression, daytime sleepiness, snoring, and insomnia. The study findings suggest that chronic sleep restriction among adolescents may increase suicidal risk. Citation: Lee YJ; Cho SJ; Cho IH; Kim SJ. Insufficient sleep and suicidality in adolescents. SLEEP 2012;35(4):455-460. PMID:22467982

Different workplace-related strains and different workplace-related anxieties in different professions.

PubMed

Muschalla, Beate; Linden, Michael

2013-08-01

Similar to the spectrum of the traditional anxiety disorders, there are also different types of workplace-related anxieties. The question is whether in different professional settings different facets of workplace-related anxieties are predominant. A convenience sample of 224 inpatients (71% women) from a department of psychosomatic medicine was investigated. They were assessed with a structured diagnostic interview concerning anxiety disorders and specific workplace-related anxieties. Office workers suffer relatively most often from specific social anxiety, insufficiency, and workplace phobia. Service workers suffer predominantly from unspecific social anxiety. Health care workers are characterized by insufficiency, adjustment disorders, posttraumatic stress disorder, and workplace phobia. Persons in production and education are least often affected by workplace-related anxieties. Different types of anxiety are seen in different professional domains, parallel to workplace characteristics.

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.

Designing trials for pressure ulcer risk assessment research: methodological challenges.

PubMed

Balzer, K; Köpke, S; Lühmann, D; Haastert, B; Kottner, J; Meyer, G

2013-08-01

For decades various pressure ulcer risk assessment scales (PURAS) have been developed and implemented into nursing practice despite uncertainty whether use of these tools helps to prevent pressure ulcers. According to current methodological standards, randomised controlled trials (RCTs) are required to conclusively determine the clinical efficacy and safety of this risk assessment strategy. In these trials, PURAS-aided risk assessment has to be compared to nurses' clinical judgment alone in terms of its impact on pressure ulcer incidence and adverse outcomes. However, RCTs evaluating diagnostic procedures are prone to specific risks of bias and threats to the statistical power which may challenge their validity and feasibility. This discussion paper critically reflects on the rigour and feasibility of experimental research needed to substantiate the clinical efficacy of PURAS-aided risk assessment. Based on reflections of the methodological literature, a critical appraisal of available trials on this subject and an analysis of a protocol developed for a methodologically robust cluster-RCT, this paper arrives at the following conclusions: First, available trials do not provide reliable estimates of the impact of PURAS-aided risk assessment on pressure ulcer incidence compared to nurses' clinical judgement alone due to serious risks of bias and insufficient sample size. Second, it seems infeasible to assess this impact by means of rigorous experimental studies since sample size would become extremely high if likely threats to validity and power are properly taken into account. Third, means of evidence linkages seem to currently be the most promising approaches for evaluating the clinical efficacy and safety of PURAS-aided risk assessment. With this kind of secondary research, the downstream effect of use of PURAS on pressure ulcer incidence could be modelled by combining best available evidence for single parts of this pathway. However, to yield reliable modelling results, more robust experimental research evaluating specific parts of the pressure ulcer risk assessment-prevention pathway is needed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Endorsement of the CONSORT guidelines, trial registration, and the quality of reporting randomised controlled trials in leading nursing journals: A cross-sectional analysis.

PubMed

Jull, Andrew; Aye, Phyu Sin

2015-06-01

To establish the reporting quality of trials published in leading nursing journals and investigate associations between CONSORT Statement or trial registration endorsment and reporting of design elements. The top 15 nursing journals were searched using Medline for randomised controlled trials published in 2012. Journals were categorised as CONSORT and trial registration promoting based on requirements of submitting authors or the journal's webpage as at January 2014. Data on sequence generation, allocation concealment, follow up, blinding, baseline equivalence and sample size calculation were extracted by one author and independently verified by the second author against source data. Seven journals were CONSORT promoting and three of these journals were also trial registration promoting. 114 citations were identified and 83 were randomised controlled trials. Eighteen trials (21.7%) were registered and those published in trial registration promoting journals were more likely to be registered (RR 2.64 95%CI 1.14-6.09). We assessed 68.7% of trials to be low risk of bias for sequence generation, 20.5% for allocation concealment, 38.6% for blinding, 55.4% for completeness of follow up and 79.5% for baseline equivalence. Trials published in CONSORT promoting journals were more likely to be at low risk of bias for blinding (RR 2.33, 95%CI 1.01-5.34) and completeness of follow up (RR 1.77, 95%CI 1.02-3.10), but journal endorsement of the CONSORT Statement or trial registration otherwise had no significant effect. Trials published in CONSORT and trial registration promoting journals were more likely to have high quality sample size calculations (RR 2.91, 95%CI 1.18-7.19 and RR 1.69, 95%CI 1.08-2.64, respectively). Simple endorsement of the CONSORT Statement and trials registration is insufficient action to encourage improvement of the quality of trial reporting across the most important of trial design elements. Copyright © 2014 Elsevier Ltd. All rights reserved.

Investigating pyroclast ejection dynamics using shock-tube experiments: temperature, grain size and vent geometry effects.

NASA Astrophysics Data System (ADS)

Cigala, V.; Kueppers, U.; Dingwell, D. B.

2015-12-01

Explosive volcanic eruptions eject large quantities of gas and particles into the atmosphere. The portion directly above the vent commonly shows characteristics of underexpanded jets. Understanding the factors that influence the initial pyroclast ejection dynamics is necessary in order to better assess the resulting near- and far-field hazards. Field observations are often insufficient for the characterization of volcanic explosions due to lack of safe access to such environments. Fortunately, their dynamics can be simulated in the laboratory where experiments are performed under controlled conditions. We ejected loose natural particles from a shock-tube while controlling temperature (25˚ and 500˚C), overpressure (15MPa), starting grain size distribution (1-2 mm, 0.5-1 mm and 0.125-0.250 mm), sample-to-vent distance and vent geometry. For each explosion we quantified the velocity of individual particles, the jet spreading angle and the production of fines. Further, we varied the setup to allow for different sample-to-gas ratios and deployed four different vent geometries: 1) cylindrical, 2) funnel with a flaring of 30˚, 3) funnel with a flaring of 15˚ and 4) nozzle. The results showed maximum particle velocities up to 296 m/s, gas spreading angles varying from 21˚ to 37˚ and particle spreading angles from 3˚ to 40˚. Moreover we observed dynamically evolving ejection characteristics and variations in the production of fines during the course of individual experiments. Our experiments mechanistically mimic the process of pyroclast ejection. Thus the capability for constraining the effects of input parameters (fragmentation conditions) and conduit/vent geometry on ballistic pyroclastic plumes has been clearly established. These data obtained in the presence of well-documented conduit and vent conditions, should greatly enhance our ability to numerically model explosive ejecta in nature.

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.

Development of an indirect method for measuring porcine pancreatic lipase in human duodenal fluid.

PubMed

Tuvignon, N; Abousalham, A; Tocques, F; De Caro, J; De Caro, A; Laugier, R; Carrière, F

2008-12-15

Patients with exocrine pancreatic insufficiency are usually treated with porcine pancreatic enzymes but the bioavailability of these enzymes in the gut remains a matter of discussion. In order to determine the duodenal availability of porcine pancreatic lipase (PPL) present in pancreatic extracts (PE) taken orally, we developed a method for quantifying PPL in samples containing both PPL and human pancreatic lipase (HPL). Total pancreatic lipase activity measurements using the pH-stat technique and tributyrin as substrate were combined with an HPL-specific ELISA. Based on the known specific activity of the purified HPL, its activity was deduced from the ELISA measurements, and the PPL activity was obtained by subtracting the HPL activity from the total pancreatic lipase activity. This assay was established and validated using various samples containing pure PPL and recombinant HPL or PE, mixed or not with human duodenal juice. Samples collected in vivo from patients treated with PE were also tested. It was found that PPL did not affect the HPL ELISA, and the indirect PPL assay gave a measurement accuracy of 6.6% with the samples containing pure PPL and 10% with those containing PE. This assay was also used successfully to discriminate between PPL and the endogenous HPL present in the duodenal contents of patients with severe pancreatic insufficiency treated with PE. This method might provide a useful means of assessing the availability of PEs at their site of action, in the absence of a PPL-specific ELISA.

Impacts of effluent from Carlsbad Desalination Plant on the coastal biology and chemistry in a in-situ study of pre- and post-discharge

NASA Astrophysics Data System (ADS)

Petersen, K. L.; Heck, N.; Paytan, A.; Potts, D. C.

2016-12-01

Ongoing droughts throughout the world and increasing water demand are creating critical water shortage in arid and semi-arid regions. Desalination of seawater is a powerful source of potable water, however the effects of the brine discharge on coastal areas are insufficiently studied. Here we report results from in-situ measurements of the effects of brine discharge from a desalination plant in Carlsbad, in Southern California before and after operation began. Operation as of December 2015. Pre-discharge samples were collected in December 2014 and September 2015. Post-discharge samples were collected in May 2016 and November 2016. Water samples are collected at the mount of the discharge channel and out to 1000 m offshore. Both surface and bottom water samples were collected and analyzed for salinity, temperature, Chl a concentration, nutrients (NO3, PO4 and silica), δ13C and δ15N of suspended matter, DOC and organic contaminants. Samples are also collected for phytoplankton cell count and sediment grain size. A biological swath was done by SCUBA divers to verify abundance and diversity of benthic organisms. The pre-discharge measurements show a homogenous water column for salinity, Chl a and nutrients. There is a slight temperature difference between the discharge channel and the intake channel due to activities of a power plant around the discharge channel. There are significantly fewer species and a lower abundance of benthic organism by the discharge channel than by the intake. This is possibly due to a higher flow rate at the discharge channel. The preliminary post-discharge analyses show a stratified water column at the discharge area. The salinity was higher by 2 to 3 salinity units at the discharge site. This trend is evident to 600 m offshore. How this affects the benthic organisms and the phytoplankton will be reported.

A comparison of soil organic matter physical fractionation methods

NASA Astrophysics Data System (ADS)

Duddigan, Sarah; Alexander, Paul; Shaw, Liz; Collins, Chris

2017-04-01

Selecting a suitable physical fractionation to investigate soil organic matter dynamics from the plethora that are available is a difficult task. An initial investigation of four different physical fractionation methods was conducted (i) Six et al. (2002); (ii) Zimmermann et al. (2007); (iii) Sohi et al. (2001); and (iv) Plaza et al. (2013). Soils used for this were from a long-term organic matter field plot study where a sandy loam soil was subjected to the following treatments: Peat (Pt), Horse Manure (H), Garden Compost (GCf), Garden Compost at half rate (GCh), and a bare plot control (BP). Although each of these methods involved the isolation of unique fractions, in the interest of comparison, each fraction was categorised as either being (i) physically protected (i.e. in aggregates); (ii) chemically protected (such as in organo-mineral complexes); or (iii) unprotected by either of these mechanisms (so-called 'free' organic matter). Regardless of the fractionation method used, a large amount of the variation in total C contents of the different treated soils is accounted for by the differences in unprotected particulate organic matter. When comparing the methods to one another there were no consistent differences in carbon content in the physically protected, chemically protected, or unprotected fractions as operationally defined across all the five organic matter treatments. Therefore fractionation method selection, for this research, was primarily driven by the practicalities of conducting each method in the lab. All of the methods tested had their limitations, for use in this research. This is not a criticism of the methods themselves but largely a result of the lack of suitability for these particular samples. For example, samples that contain a lot of gravel can lead to problems for methods that use size distribution for fractionation. Problems can also be encountered when free particulate organic matter contributes a large proportion of the sample, leaving insufficient sample for further fractionation. This highlights the need for an understanding of the nature of your sample prior to method selection.

Increased hallux angle in children and its association with insufficient length of footwear: a community based cross-sectional study.

PubMed

Klein, Christian; Groll-Knapp, Elisabeth; Kundi, Michael; Kinz, Wieland

2009-12-17

Wearing shoes of insufficient length during childhood has often been cited as leading to deformities of the foot, particularly to the development of hallux valgus disorders. Until now, these assumptions have not been confirmed through scientific research. This study aims to investigate whether this association can be statistically proven, and if children who wear shoes of insufficient length actually do have a higher risk of a more pronounced lateral deviation of the hallux. 858 pre-school children were included in the study. The study sample was stratified by sex, urban/rural areas and Austrian province. The hallux angle and the length of the feet were recorded. The inside length of the children's footwear (indoor shoes worn in pre-school and outdoor shoes) were assessed. Personal data and different anthropometric measurements were taken. The risk of hallux valgus deviation was statistically tested by a stepwise logistic regression analysis and the relative risk (odds ratio) for a hallux angle > or = 4 degrees was calculated. Exact examinations of the hallux angle could be conducted on a total of 1,579 individual feet. Only 23.9% out of 1,579 feet presented a straight position of the great toe. The others were characterized by lateral deviations (valgus position) at different degrees, equalling 10 degrees or greater in 14.2% of the children's feet.88.8% of 808 children examined wore indoor footwear that was of insufficient length, and 69.4% of 812 children wore outdoor shoes that were too short. A significant relationship was observed between the lengthwise fit of the shoes and the hallux angle: the shorter the shoe, the higher the value of the hallux angle. The relative risk (odds ratio) of a lateral hallux deviation of > or = 4 degrees in children wearing shoes of insufficient length was significantly increased. There is a significant relationship between the hallux angle in children and footwear that is too short in length. The fact that the majority of the children examined were wearing shoes of insufficient length makes the issue particularly significant. Our results emphasize the importance of ensuring that children's footwear fits properly.

The accuracy of endometrial sampling in women with postmenopausal bleeding: a systematic review and meta-analysis.

PubMed

van Hanegem, Nehalennia; Prins, Marileen M C; Bongers, Marlies Y; Opmeer, Brent C; Sahota, Daljit Singh; Mol, Ben Willem J; Timmermans, Anne

2016-02-01

Postmenopausal bleeding (PMB) can be the first sign of endometrial cancer. In case of thickened endometrium, endometrial sampling is often used in these women. In this systematic review, we studied the accuracy of endometrial sampling for the diagnoses of endometrial cancer, atypical hyperplasia and endometrial disease (endometrial pathology, including benign polyps). We systematically searched the literature for studies comparing the results of endometrial sampling in women with postmenopausal bleeding with two different reference standards: blind dilatation and curettage (D&C) and hysteroscopy with histology. We assessed the quality of the detected studies by the QUADAS-2 tool. For each included study, we calculated the fraction of women in whom endometrial sampling failed. Furthermore, we extracted numbers of cases of endometrial cancer, atypical hyperplasia and endometrial disease that were identified or missed by endometrial sampling. We detected 12 studies reporting on 1029 women with postmenopausal bleeding: five studies with dilatation and curettage (D&C) and seven studies with hysteroscopy as a reference test. The weighted sensitivity of endometrial sampling with D&C as a reference for the diagnosis of endometrial cancer was 100% (range 100-100%) and 92% (71-100) for the diagnosis of atypical hyperplasia. Only one study reported sensitivity for endometrial disease, which was 76%. When hysteroscopy was used as a reference, weighted sensitivities of endometrial sampling were 90% (range 50-100), 82% (range 56-94) and 39% (21-69) for the diagnosis of endometrial cancer, atypical hyperplasia and endometrial disease, respectively. For all diagnosis studied and the reference test used, specificity was 98-100%. The weighted failure rate of endometrial sampling was 11% (range 1-53%), while insufficient samples were found in 31% (range 7-76%). In these women with insufficient or failed samples, an endometrial (pre) cancer was found in 7% (range 0-18%). In women with postmenopausal bleeding, the sensitivity of endometrial sampling to detect endometrial cancer and especially atypical hyperplasia and endometrial disease, including endometrial polyps, is lower than previously thought. Therefore, further diagnostic work-up for focal pathology is warranted, after a benign result of endometrial sampling. Copyright © 2015. Published by Elsevier Ireland Ltd.

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.

An Inexpensive High-Temporal Resolution Electronic Sun Journal for Monitoring Personal Day to Day Sun Exposure Patterns

PubMed Central

Downs, Nathan J.; Parisi, Alfio V.; Butler, Harry; Rawlings, Alex; Elrahoumi, Raja Salem

2017-01-01

Exposure to natural sunlight, specifically solar ultraviolet (UV) radiation contributes to lifetime risks of skin cancer, eye disease, and diseases associated with vitamin D insufficiency. Improved knowledge of personal sun exposure patterns can inform public health policy; and help target high-risk population groups. Subsequently, an extensive number of studies have been conducted to measure personal solar UV exposure in a variety of settings. Many of these studies, however, use digital or paper-based journals (self-reported volunteer recall), or employ cost prohibitive electronic UV dosimeters (that limit the size of sample populations), to estimate periods of exposure. A cost effective personal electronic sun journal (ESJ) built from readily available infrared photodiodes is presented in this research. The ESJ can be used to complement traditional UV dosimeters that measure total biologically effective exposure by providing a time-stamped sun exposure record. The ESJ can be easily attached to clothing and data logged to personal devices (including fitness monitors or smartphones). The ESJ improves upon self-reported exposure recording and is a cost effective high-temporal resolution option for monitoring personal sun exposure behavior in large population studies. PMID:29201865

Magnetic resonance tomography of the knee joint.

PubMed

Puig, Stefan; Kuruvilla, Yojena Chittazhathu Kurian; Ebner, Lukas; Endel, Gottfried

2015-10-01

To compare the diagnostic performance of magnetic resonance imaging (MRI) in terms of sensitivity and specificity using a field strength of <1.0 T (T) versus ≥1.5 T for diagnosing or ruling out knee injuries or knee pathologies. The systematic literature research revealed more than 10,000 references, of which 1598 abstracts were reviewed and 87 full-text articles were retrieved. The further selection process resulted in the inclusion of four systematic reviews and six primary studies. No differences could be identified in the diagnostic performance of low- versus high-field MRI for the detection or exclusion of meniscal or cruciate ligament tears. Regarding the detection or grading of cartilage defects and osteoarthritis of the knee, the existing evidence suggests that high-field MRI is tolerably specific but not very sensitive, while there is literally no evidence for low-field MRI because only a few studies with small sample sizes and equivocal findings have been performed. We can recommend the use of low-field strength MRI systems in suspected meniscal or cruciate ligament injuries. This does, however, not apply to the diagnosis and grading of knee cartilage defects and osteoarthritis because of insufficient evidence.

Forensic nursing science knowledge and competency: the use of simulation.

PubMed

Drake, Stacy A; Langford, Rae; Young, Anne; Ayers, Constance

2015-01-01

Forensic nursing is a nursing specialty that provides services to a variety of patient populations who have experienced violence, including interpersonal violence, sudden or unexpected death, and motor vehicle collisions. However, many critical care nurses have received the background knowledge or practical skills required to provide the level of care required by many forensic patients. The purpose of this study was to determine whether differences in knowledge or practical competence exist between participants using 2 different learning modalities: medium fidelity simulation versus face-to-face lecture. Participants who were enrolled in an elective online forensic nursing science course were randomly assigned to an intervention or control group. The 18 intervention group participants were given three 2-hour forensic simulation sessions in the laboratory. The 17 control group participants attended 3 face-to-face lectures covering forensic science topics. All study participants also received the same forensic course content via the online Blackboard platform. No significant differences were found between the 2 groups in either knowledge or practical competency. The lack of results may have been heavily influenced by the small sample size, which resulted in insufficient power to detect possible differences.

Evaluation of reporting quality for observational studies using routinely collected health data in pharmacovigilance.

PubMed

Nie, Xiaolu; Zhang, Ying; Wu, Zehao; Jia, Lulu; Wang, Xiaoling; Langan, Sinéad M; Benchimol, Eric I; Peng, Xiaoxia

2018-06-01

To appraise the reporting quality of studies which concerned linezolid related thrombocytopenia referring to REporting of studies Conducted using Observational Routinely-collected health Data (RECORD) statement. Medline, Embase, Cochrane library and clinicaltrial.gov were searched for observational studies concerning linezolid related thrombocytopenia using routinely collected health data from 2000 to 2017. Two reviewers screened potential eligible articles and extracted data independently. Finally, reporting quality assessment was performed by two senior researchers using RECORD statement. Of 25 included studies, 11 (44.0%) mentioned the type of data in the title and/or abstract. In 38 items derived from RECORD statement, the median number of items reported in the included studies was 22 (interquartile range (IQR) 18 to 27). Inadequate reporting issues were discovered in the following aspects: validation studies of the codes or algorithms, study size estimation, quantitative variables, subgroup statistical methods, missing data, follow-up/matching or sampling strategy, sensitivity analysis and cleaning methods, funding and role of funders and accessibility of protocol, raw data. This study provides the evidence that the reporting quality of post-marketing safety evaluation studies conducted using routinely collected health data was often insufficient. Future stakeholders are encouraged to endorse the RECORD guidelines in pharmacovigilance.

Hypnosis and movement disorders: State of the art and perspectives.

PubMed

Flamand-Roze, C; Célestin-Lhopiteau, I; Roze, E

Hypnosis might represent an interesting complementary therapeutic approach to movement disorders, as it takes into account not only symptoms, but also well-being, and empowers patients to take a more active role in their treatment. Our review of the literature on the use of hypnosis to treat movement disorders was done by systematically searching the PubMed database for reports published between 1984 and November 2015. The following variables were extracted from each selected paper: study design; sample size; type of movement disorder; hypnotic procedure; treatment duration; and efficacy. Thirteen papers were selected for detailed analysis. Most concerned tremor in Parkinson's disease and tics in Gilles de la Tourette syndrome. Although promising, the data were insufficient to allow conclusions to be drawn on the efficacy of hypnosis in movement disorders or to recommend its use in this setting. Well-designed studies taking into account some specific methodological challenges are needed to determine the possible therapeutic utility of hypnosis in movement disorders. In addition to the potential benefits for such patients, hypnosis might also be useful for studying the neuroanatomical and functional underpinnings of normal and abnormal movements. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

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

[THE GIFT OF THE APPLICATION OF REIKI THERAPY IN CANCER PATIENTS].

PubMed

Sánchez Domínguez, Javier

2016-06-01

Pain is one of the most feared symptoms of cancer. Bad pain not properly relieved contributes to the suffering of the patient and family. This may encourage them to seek additional complementary and alternative therapies, such as the one in our literature review. Reiki is understood as a healing method that uses universal energy to achieve balance and harmony of body, mind and soul, through the laying on of hands. Reiki is a relatively new the rapyin relation to the relief of the symptoms of cancer. In fact, there are still a few articles in this field. Currently, the authors explore the evidence on the effectiveness of Reiki in relation to cancer pain and symptom control. Due to the increased interest deposited in Reiki by the health professionals--especially for oncology professionals--to relieve the symptoms of cancer, there has been a synthesis of recent studies to provide the evidence so far. After our literature review, we can conclude that there is insufficient evidence on the effectiveness of Reiki in relieving the cancer's symptoms due to the small sample size used, the paucity of studies and the abandonment of the study participants and others.

Base-Rate Neglect as a Function of Base Rates in Probabilistic Contingency Learning

ERIC Educational Resources Information Center

Kutzner, Florian; Freytag, Peter; Vogel, Tobias; Fiedler, Klaus

2008-01-01

When humans predict criterion events based on probabilistic predictors, they often lend excessive weight to the predictor and insufficient weight to the base rate of the criterion event. In an operant analysis, using a matching-to-sample paradigm, Goodie and Fantino (1996) showed that humans exhibit base-rate neglect when predictors are associated…

An Evaluation of a Worksite Exercise Intervention Using the Social Cognitive Theory: A Pilot Study

ERIC Educational Resources Information Center

Amaya, Megan; Petosa, R. L.

2012-01-01

Purpose: To increase exercise adherence among insufficiently active adult employees. Design: A quasi-experimental separate samples pre-test-post-test group design was used to compare treatment and comparison group. Setting: The worksite. Subjects: Employees (n = 127) who did not meet current American College of Sports Medicine (ACSM)…

Brazilian spotted fever: description of a fatal clinical case in the State of Rio de Janeiro.

PubMed

de Lemos, Elba Regina Sampaio; Rozental, Tatiana; Villela, Cid Leite

2002-01-01

We describe a case of Brazilian spotted fever in a previously healthy young woman who died with petechial rash associated to acute renal and respiratory insufficiency 12 days following fever, headache, myalgia, and diarrhea. Serologic test in a serum sample, using an immunofluorescence assay, revealed reactive IgM/IgG.

Gang Membership, School Violence, and the Mediating Effects of Risk and Protective Behaviors in California High Schools

ERIC Educational Resources Information Center

Estrada, Joey Nuñez, Jr.; Gilreath, Tamika D.; Astor, Ron Avi; Benbenishty, Rami

2014-01-01

There is insufficient empirical evidence exploring associations between gang membership and school violence behaviors. Using a sample of 272,863 high school students, this study employs a structural equation model to examine how school risk and protective behaviors and attitudes mediate effects of gang members' involvement with school violence…

A Sample Practical Report to Facilitate Writing in the Scientific Style

ERIC Educational Resources Information Center

Corradi, Hazel Ruth

2012-01-01

The ability to write concise and accurate scientific reports is highly valued in university level science. From reflection on marking student final year reports, it was apparent that many students have had insufficient practice at writing complete "scientific paper" style reports by that time, although some do it very well. This is a previously…

A National Overview of the Training Received by Certified Nursing Assistants Working in U.S. Nursing Homes

ERIC Educational Resources Information Center

Sengupta, Manisha; Harris-Kojetin, Lauren D.; Ejaz, Farida K.

2010-01-01

A few geographically limited studies have indicated that training of direct care workers may be insufficient. Using the first-ever nationally representative sample of certified nursing assistants (CNAs) from the 2004 National Nursing Assistant Survey (NNAS), this descriptive article provides an overview of the type of initial training and…

Continuing Education of Nurses in Lebanon: Evaluation and Unmet Needs

ERIC Educational Resources Information Center

Salameh, Pascale R.; Barbour, Bernadette

2006-01-01

In the nursing profession it is necessary for a nurse to engage in continuing education to keep up to date. In Lebanon efforts to establish such continuing education are being made. However, a cross-sectional study conducted on a representative sample of 254 nurses found that 60 per cent attend an insufficient number of continuing education…

[Latest advances in chronic pancreatitis].

PubMed

Domínguez Muñoz, J Enrique

2015-09-01

This article summarizes some of the recent and clinically relevant advances in chronic pancreatitis. These advances mainly concern the early diagnosis of the disease, the treatment of symptoms and complications, mainly pain and pancreatic exocrine insufficiency, and the diagnosis and therapy of autoimmune pancreatitis. The multimodal dynamic endoscopic ultrasound-guided secretin-stimulated evaluation of the pancreas provides relevant morphological and functional information for the diagnosis of chronic pancreatitis at early stages. Extracorporeal shock wave lithotripsy in patients with calcifying pancreatitis and endoscopic pancreatic stent placement are effective alternatives for pain therapy in patients with chronic pancreatitis. Presence of pancreatic exocrine insufficiency in patients with chronic pancreatitis is associated with a significantly increase of mortality rate. Despite that, pancreatic enzyme replacement therapy is not prescribed in the majority of patients with pancreatic exocrine insufficiency, or it is prescribed at a low dose. The newly developed and commercialized needles for endoscopic ultrasound-guided pancreatic biopsy are effective in retrieving appropriate tissue samples for the histological diagnosis of autoimmune pancreatitis. Maintenance therapy with azathioprine is effective and safe to prevent relapses in patients with autoimmune pancreatitis. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

The association of psychosocial and familial factors with adolescent suicidal ideation: A population-based study.

PubMed

An, Hoyoung; Ahn, Joon-ho; Bhang, Soo-young

2010-05-30

We aimed to compare the influence of various parental factors on adolescent suicidal ideas from a population-based sample of 2965 adolescents between 15 to 18 years-old, and their parents. Among the subject variables, gender, satisfaction with one's health, having an illness, and satisfaction with family; and among parental variables, fathers' satisfaction with health; mothers' insufficient sleep; parents' history of suicidal ideation, and satisfaction with family were significantly different in adolescents who reported suicidal ideation compared to those who reported none. Odds ratios indicated increased risk of adolescent suicidal ideation was associated with the subject factors female gender, insufficient sleep, dissatisfaction with one's health, dissatisfaction with family, and with maternal data showing insufficient sleep and a positive history of suicidal impulse. A path analysis model (comparative fit index (CFI)=0.907; root mean square error of approximation (RMSEA)=0.047), indicated psychosocial factors (beta=0.232) had a greater influence on adolescent suicidal ideation than did genetic factors (beta=0.120). These results show psychosocial factors have an almost two-fold greater influence on adolescent suicidal ideation than genetic factors. Assessment and modification of these factors would greatly assist future interventions. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

A work-life perspective on sleep and fatigue—looking beyond shift workers

PubMed Central

SKINNER, Natalie; DORRIAN, Jill

2015-01-01

This study examines sleep and fatigue through a work-life lens. Whilst most often thought of as an issue for shift workers, this study observed that self-reported insufficient sleep and fatigue were prevalent for workers on standard daytime schedules. Using a representative sample of 573 daytime workers (51.3% men; 70.7% aged 25−54 yr) from one Australian state, it was observed that 26.4% of daytime workers never or rarely get the seven hours of sleep a night that is recommended for good health. Those with parenting responsibilites (29.4%) or working long (45+) hours (37.4%) were most likely to report insufficient sleep. Whereas mothers in full-time work were most likely to report frequent fatigue (42.5%). This study highlights the common experience of insufficient sleep and fatigue in a daytime workforce, with significant implications for health and safety at work and outside of work. Stronger and more effective legislation addressing safe and ‘decent’ working time is clearly needed, along with greater awareness and acceptance within workplace cultures of the need to support reasonable workloads and working hours. PMID:26027709

Cost-effectiveness Analysis of an Aftercare Service vs Treatment-As-Usual for Patients with Severe Mental Disorders.

PubMed

Barfar, Eshagh; Sharifi, Vandad; Amini, Homayoun; Mottaghipour, Yasaman; Yunesian, Masud; Tehranidoost, Mehdi; Sobhebidari, Payam; Rashidian, Arash

2017-09-01

There have been claims that community mental health principles leads to the maintenance of better health and functioning in patients and can be more economical for patients with severe and chronic mental disorders. Economic evaluation studies have been used to assess the cost-effectiveness of national health programs, or to propose efficient strategies for health care delivery. The current study is intended to test the cost-effectiveness of an Aftercare Service when compared with Treatment-As-Usual for patients with severe mental disorders in Iran. This study was a parallel group randomized controlled trial. A total of 160 post-discharge eligible patients were randomized into two equal patient groups, Aftercare Service (that includes either Home Visiting Care, or Telephone Follow-up for outpatient treatment) vs Treatment-As-Usual, using stratified balanced block randomization method. All patients were followed for 12 months after discharge. The perspective of the present study was the societal perspective. The outcome measures were the rate of readmission at the hospitals after discharge, psychotic symptoms, manic symptoms, depressive symptoms, illness severity, global functioning, quality of life, and patients' satisfaction with the services. The costs included the intervention costs and the patient and family costs in the evaluation period. There was no significant difference in effectiveness measures between the two groups. The Aftercare Service arm was about 66,000 US$ cheaper than Treatment-As-Usual arm. The average total cost per patient in the Treatment-As-Usual group was about 4651 USD, while it was reduced to 3823 US$ in the Aftercare Service group; equivalent to a cost reduction of about 800 USD per patient per year. Given that there was no significant difference in effectiveness measures between the two groups (slightly in favor of the intervention), the Aftercare Service was cost-effective. The most important limitation of the study was the relatively small sample size due to limited budget for the implementation of the study. A larger sample size and longer follow-ups are warranted. Considering the limited resources and equity concerns for health systems, the importance of making decisions about healthcare interventions based on cost-effectiveness evidence is increasing. Our results suggest that the aftercare service can be recommended as an efficient service delivery mode, especially when psychiatric bed requirements are insufficient for a population. Further research should continue the work done with a larger sample size and longer follow-ups to further establish the cost-effectiveness analysis of an aftercare service program compared with routine conventional care.

Direct and accurate measurement of size dependent wetting behaviors for sessile water droplets

PubMed Central

Park, Jimin; Han, Hyung-Seop; Kim, Yu-Chan; Ahn, Jae-Pyeong; Ok, Myoung-Ryul; Lee, Kyung Eun; Lee, Jee-Wook; Cha, Pil-Ryung; Seok, Hyun-Kwang; Jeon, Hojeong

2015-01-01

The size-dependent wettability of sessile water droplets is an important matter in wetting science. Although extensive studies have explored this problem, it has been difficult to obtain empirical data for microscale sessile droplets at a wide range of diameters because of the flaws resulting from evaporation and insufficient imaging resolution. Herein, we present the size-dependent quantitative change of wettability by directly visualizing the three phase interfaces of droplets using a cryogenic-focused ion beam milling and SEM-imaging technique. With the fundamental understanding of the formation pathway, evaporation, freezing, and contact angle hysteresis for sessile droplets, microdroplets with diameters spanning more than three orders of magnitude on various metal substrates were examined. Wetting nature can gradually change from hydrophobic at the hundreds-of-microns scale to super-hydrophobic at the sub-μm scale, and a nonlinear relationship between the cosine of the contact angle and contact line curvature in microscale water droplets was demonstrated. We also showed that the wettability could be further tuned in a size-dependent manner by introducing regular heterogeneities to the substrate. PMID:26657208

Footwear in rock climbing: Current practice.

PubMed

McHenry, R D; Arnold, G P; Wang, W; Abboud, R J

2015-09-01

Many rock climbers wear ill-fitting and excessively tight footwear during activity. However, there is insufficient evidence of the extent or harms of this practice. To investigate footwear use in rock climbers with a focus on issues surrounding fit. A cross-sectional study with active rock climbers of over one year of experience completing a survey on their activity and footwear. Additionally, the authors quantified foot and shoe lengths and sizes alongside demographic data. Ill-fitting and excessively tight footwear was found in 55 out of 56 rock climbers. Foot pain during activity was also commonplace in 91% of the climbers. A mean size reduction of almost 4 UK shoe sizes was found between the climbers' street shoe size and that of their climbing footwear using a calibrated foot/shoe ruler. There is an unfortunate association of climbers of higher abilities seeking a tighter shoe fit (p<0.001). With the elucidation of footwear use amongst rock climbers, further investigation may aim to quantify its impact and seek a solution balancing climbing performance while mitigating foot injury. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

Spanking, corporal punishment and negative long-term outcomes: a meta-analytic review of longitudinal studies.

PubMed

Ferguson, Christopher J

2013-02-01

Social scientists continue to debate the impact of spanking and corporal punishment (CP) on negative child outcomes including externalizing and internalizing behavior problems and cognitive performance. Previous meta-analytic reviews have mixed long- and short-term studies and relied on bivariate r, which may inflate effect sizes. The current meta-analysis focused on longitudinal studies, and compared effects using bivariate r and better controlled partial r coefficients controlling for time-1 outcome variables. Consistent with previous findings, results based on bivariate r found small but non-trivial long-term relationships between spanking/CP use and negative outcomes. Spanking and CP correlated .14 and .18 respectively with externalizing problems, .12 and .21 with internalizing problems and -.09 and -.18 with cognitive performance. However, when better controlled partial r coefficients (pr) were examined, results were statistically significant but trivial (at or below pr = .10) for externalizing (.07 for spanking, .08 for CP) and internalizing behaviors (.10 for spanking, insufficient studies for CP) and near the threshold of trivial for cognitive performance (-.11 for CP, insufficient studies for spanking). It is concluded that the impact of spanking and CP on the negative outcomes evaluated here (externalizing, internalizing behaviors and low cognitive performance) are minimal. It is advised that psychologists take a more nuanced approach in discussing the effects of spanking/CP with the general public, consistent with the size as well as the significance of their longitudinal associations with adverse outcomes.

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...

Assessment of adult pallid sturgeon fish condition, Lower Missouri River—Application of new information to the Missouri River Recovery Program

USGS Publications Warehouse

Randall, Michael T.; Colvin, Michael E.; Steffensen, Kirk D.; Welker, Timothy L.; Pierce, Landon L.; Jacobson, Robert B.

2017-10-11

During spring 2015, Nebraska Game and Parks Commission (NGPC) biologists noted that pallid sturgeon (Scaphirhynchus albus) were in poor condition during sampling associated with the Pallid Sturgeon Population Assessment Project and NGPC’s annual pallid sturgeon broodstock collection effort. These observations prompted concerns that reduced fish condition could compromise reproductive health and population growth of pallid sturgeon. There was a further concern that compromised condition could possibly be linked to U.S. Army Corps of Engineers management actions and increase jeopardy to the species. An evaluation request was made to the Missouri River Recovery Program and the Effects Analysis Team was chartered to evaluate the issue. Data on all Missouri River pallid sturgeon captures were requested and received from the National Pallid Sturgeon Database. All data were examined for completeness and accuracy; 12,053 records of captures between 200 millimeters fork length (mm FL) and 1,200 mm FL were accepted. We analyzed condition using (1) the condition formula (Kn) from Shuman and others (2011); (2) a second Kn formulation derived from the 12,053 records (hereafter referred to as “Alternative Kn”); and (3) an analysis of covariance (ANCOVA) approach that did not rely on a Kn formulation. The Kn data were analyzed using group (average annual Kn) and individual (percentage in low, normal, and robust conditions) approaches. Using the Shuman Kn formulation, annual mean Kn was fairly static from 2005 to 2011 (although always higher in the upper basin), declined from 2012 to 2015, then remained either static (lower basin) or increasing (upper basin) in 2016. Under the Alternative Kn formulation, the upper basin showed no decline in Kn, whereas the lower basin displayed the same trend as the Shuman Kn formulation. Using both formulations, the individual approach revealed a more complex situation; at the same times and locations that there are fish in poor condition, there are nearby fish in normal or robust condition. The ANCOVA approach revealed that fish condition at size changed between 400 and 600 mm and that some of the apparent trend in low condition was caused by differences in sample size across the size range of the population (that is, greater catch of intermediate-sized fish compared to large fish). We examined basin, year, origin (hatchery compared to wild), segment, and size class for effects on condition and concluded that, since 2012, there has been an increase in the percentage of pallid sturgeon in low condition. There are basin, year, and segment effects; origin and size class do not seem to have an effect. The lower basin, in particular segment 9 (Platte River to Kansas River), had a high percentage of low-condition fish. Within the segment, there were bend-level effects, but the bend effect was not spatially contiguous. We concluded that existing data confirm concerns about declining fish condition, especially in the segments between Sioux City, Iowa, and Kansas City, Missouri. Although the evidence is strong that fish condition has been in decline from 2011 to 2015, additional analysis of individual fish histories may provide more confidence in this conclusion; such analysis was beyond the scope of this effort but is part of our recommendations. The most recent data in 2016 indicate that decline of condition may have leveled off; however, the length of record is insufficient to determine whether recent declines are within the background range of variation. We recommend that monitoring of fish condition should be increased and enhanced with additional health metrics. We also recommend that, should condition continue to decline, processes are deployed to bring low-condition adult fish into the hatchery to improve nutrition and condition. We could not determine the cause of declining fish condition with available data, but we compiled information on several dominant hypotheses in two main categories: inter- or intraspecific competition for resources and habitat conditions. Data are insufficient to indicate a specific causation or solution, and it is possible that multiple causes apply. We make recommendations for additional research that can be pursued to address uncertainties in trends in fish health as well as potential causes.

Electrolyte matrix in a molten carbonate fuel cell stack

DOEpatents

Reiser, C.A.; Maricle, D.L.

1987-04-21

A fuel cell stack is disclosed with modified electrolyte matrices for limiting the electrolytic pumping and electrolyte migration along the stack external surfaces. Each of the matrices includes marginal portions at the stack face of substantially greater pore size than that of the central body of the matrix. Consequently, these marginal portions have insufficient electrolyte fill to support pumping or wicking of electrolyte from the center of the stack of the face surfaces in contact with the vertical seals. Various configurations of the marginal portions include a complete perimeter, opposite edge portions corresponding to the air plenums and tab size portions corresponding to the manifold seal locations. These margins will substantially limit the migration of electrolyte to and along the porous manifold seals during operation of the electrochemical cell stack. 6 figs.

Electrolyte matrix in a molten carbonate fuel cell stack

DOEpatents

Reiser, Carl A.; Maricle, Donald L.

1987-04-21

A fuel cell stack is disclosed with modified electrolyte matrices for limiting the electrolytic pumping and electrolyte migration along the stack external surfaces. Each of the matrices includes marginal portions at the stack face of substantially greater pore size than that of the central body of the matrix. Consequently, these marginal portions have insufficient electrolyte fill to support pumping or wicking of electrolyte from the center of the stack of the face surfaces in contact with the vertical seals. Various configurations of the marginal portions include a complete perimeter, opposite edge portions corresponding to the air plenums and tab size portions corresponding to the manifold seal locations. These margins will substantially limit the migration of electrolyte to and along the porous manifold seals during operation of the electrochemical cell stack.

Versatile microrobotics using simple modular subunits

NASA Astrophysics Data System (ADS)

Cheang, U. Kei; Meshkati, Farshad; Kim, Hoyeon; Lee, Kyoungwoo; Fu, Henry Chien; Kim, Min Jun

2016-07-01

The realization of reconfigurable modular microrobots could aid drug delivery and microsurgery by allowing a single system to navigate diverse environments and perform multiple tasks. So far, microrobotic systems are limited by insufficient versatility; for instance, helical shapes commonly used for magnetic swimmers cannot effectively assemble and disassemble into different size and shapes. Here by using microswimmers with simple geometries constructed of spherical particles, we show how magnetohydrodynamics can be used to assemble and disassemble modular microrobots with different physical characteristics. We develop a mechanistic physical model that we use to improve assembly strategies. Furthermore, we experimentally demonstrate the feasibility of dynamically changing the physical properties of microswimmers through assembly and disassembly in a controlled fluidic environment. Finally, we show that different configurations have different swimming properties by examining swimming speed dependence on configuration size.

Versatile microrobotics using simple modular subunits

PubMed Central

Cheang, U Kei; Meshkati, Farshad; Kim, Hoyeon; Lee, Kyoungwoo; Fu, Henry Chien; Kim, Min Jun

2016-01-01

The realization of reconfigurable modular microrobots could aid drug delivery and microsurgery by allowing a single system to navigate diverse environments and perform multiple tasks. So far, microrobotic systems are limited by insufficient versatility; for instance, helical shapes commonly used for magnetic swimmers cannot effectively assemble and disassemble into different size and shapes. Here by using microswimmers with simple geometries constructed of spherical particles, we show how magnetohydrodynamics can be used to assemble and disassemble modular microrobots with different physical characteristics. We develop a mechanistic physical model that we use to improve assembly strategies. Furthermore, we experimentally demonstrate the feasibility of dynamically changing the physical properties of microswimmers through assembly and disassembly in a controlled fluidic environment. Finally, we show that different configurations have different swimming properties by examining swimming speed dependence on configuration size. PMID:27464852

Software Support for Transiently Powered Computers

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

Van Der Woude, Joel Matthew

With the continued reduction in size and cost of computing, power becomes an increasingly heavy burden on system designers for embedded applications. While energy harvesting techniques are an increasingly desirable solution for many deeply embedded applications where size and lifetime are a priority, previous work has shown that energy harvesting provides insufficient power for long running computation. We present Ratchet, which to the authors knowledge is the first automatic, software-only checkpointing system for energy harvesting platforms. We show that Ratchet provides a means to extend computation across power cycles, consistent with those experienced by energy harvesting devices. We demonstrate themore » correctness of our system under frequent failures and show that it has an average overhead of 58.9% across a suite of benchmarks representative for embedded applications.« less

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...

On the Hipparcos Link to the ICRF derived from VLA and MERLIN radio astrometry

NASA Astrophysics Data System (ADS)

Hering, R.; Walter, H. G.

2007-06-01

Positions and proper motions obtained from observations by the very large array (VLA) and the multi-element radio-linked interferometer network (MERLIN) are used to establish the link of the Hipparcos Celestial Reference Frame (HCRF) to the International Celestial Reference Frame (ICRF). The VLA and MERLIN data are apparently the latest ones published in the literature. Their mean epoch at around 2001 is about 10 years after the epoch of the Hipparcos catalogue and, therefore, the data are considered suitable to check the Hipparcos link established at epoch 1991.25. The parameters of the link, i.e., the angles of frame orientation and the angular rates of frame rotation, are estimated by fitting these parameters to the differences of the optical and radio positions and proper motions of stars common to the Hipparcos catalogue and the VLA and MERLIN data. Both the estimates of the angles of orientation and the angular rates of rotation show nearly consistent but insignificant results for all samples of stars treated. We conclude that not only the size of the samples of 9 15 stars is too small, but also that the accuracy of the radio positions and, above all, of the radio proper motions is insufficient, the latter being based on early-epoch star positions of low accuracy. The present observational data at epoch 2001 suggest that maintenance of the Hipparcos frame is not feasible at this stage.

The influence of exposure and physiology on microplastic ingestion by the freshwater fish Rutilus rutilus (roach) in the River Thames, UK.

PubMed

Horton, Alice A; Jürgens, Monika D; Lahive, Elma; van Bodegom, Peter M; Vijver, Martina G

2018-05-01

Microplastics are widespread throughout aquatic environments. However, there is currently insufficient understanding of the factors influencing ingestion of microplastics by organisms, especially higher predators such as fish. In this study we link ingestion of microplastics by the roach Rutilus rutilus, within the non-tidal part of the River Thames, to exposure and physiological factors. Microplastics were found within the gut contents of roach from six out of seven sampling sites. Of sampled fish, 33% contained at least one microplastic particle. The majority of particles were fibres (75%), with fragments and films also seen (22.7% and 2.3% respectively). Polymers identified were polyethylene, polypropylene and polyester, in addition to a synthetic dye. The maximum number of ingested microplastic particles for individual fish was strongly correlated to exposure (based on distance from the source of the river). Additionally, at a given exposure, the size of fish correlated with the actual quantity of microplastics in the gut. Larger (mainly female) fish were more likely to ingest the maximum possible number of particles than smaller (mainly male) fish. This study is the first to show microplastic ingestion within freshwater fish in the UK and provides valuable new evidence of the factors influencing ingestion that can be used to inform future studies on exposure and hazard of microplastics to fish. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

A Family-Based Randomized Controlled Trial of Pain Intervention for Adolescents with Sickle Cell Disease

PubMed Central

Barakat, Lamia P.; Schwartz, Lisa A.; Salamon, Katherine S.; Radcliffe, Jerilynn

2010-01-01

The study had two aims--to determine the efficacy of a family-based cognitive-behavioral pain management intervention for adolescents with sickle cell disease (SCD) in (1) reducing pain and improving health-related variables and (2) improving psychosocial outcomes. Each adolescent and a family support person were randomly assigned to receive a brief pain intervention (PAIN) (n = 27) or a disease education attention control intervention (DISEASE ED) (n = 26) delivered at home. Assessment of primary pain and health-related variables (health service use, pain coping, pain-related hindrance of goals) and secondary psychosocial outcomes (disease knowledge, disease self-efficacy, and family communication) occurred at baseline (prior to randomization), post-intervention, and one-year follow-up. Change on outcomes did not differ significantly by group at either time point. When groups were combined in exploratory analyses, there was evidence of small to medium effects of intervention on health-related and psychosocial variables. Efforts to address barriers to participation and improve feasibility of psychosocial interventions for pediatric SCD are critical to advancing development of effective treatments for pain. Sample size was insufficient to adequately test efficacy, and analyses did not support this focused cognitive-behavioral pain management intervention in this sample of adolescents with SCD. Exploratory analyses suggest that comprehensive interventions, that address a broad range of skills related to disease management and adolescent health concerns, may be more effective in supporting teens during healthcare transition. PMID:20686425

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.

Small for Size and Flow (SFSF) syndrome: An alternative description for posthepatectomy liver failure.

PubMed

Golriz, Mohammad; Majlesara, Ali; El Sakka, Saroa; Ashrafi, Maryam; Arwin, Jalal; Fard, Nassim; Raisi, Hanna; Edalatpour, Arman; Mehrabi, Arianeb

2016-06-01

Small for Size Syndrome (SFSS) syndrome is a recognizable clinical syndrome occurring in the presence of a reduced mass of liver, which is insufficient to maintain normal liver function. A definition has yet to be fully clarified, but it is a common clinical syndrome following partial liver transplantation and extended hepatectomy, which is characterized by postoperative liver dysfunction with prolonged cholestasis and coagulopathy, portal hypertension, and ascites. So far, this syndrome has been discussed with focus on the remnant size of the liver after partial liver transplantation or extended hepatectomy. However, the current viewpoints believe that the excessive flow of portal vein for the volume of the liver parenchyma leads to over-pressure, sinusoidal endothelial damages and haemorrhage. The new hypothesis declares that in both extended hepatectomy and partial liver transplantation, progression of Small for Size Syndrome is not determined only by the "size" of the liver graft or remnant, but by the hemodynamic parameters of the hepatic circulation, especially portal vein flow. Therefore, we suggest the term "Small for Size and Flow (SFSF)" for this syndrome. We believe that it is important for liver surgeons to know the pathogenesis and manifestation of this syndrome to react early enough preventing non-reversible tissue damages. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Hamstring autograft size importance in anterior cruciate ligament repair surgery

PubMed Central

Figueroa, Francisco; Figueroa, David; Espregueira-Mendes, João

2018-01-01

Graft size in hamstring autograft anterior cruciate ligament (ACL) surgery is an important factor directly related to failure. Most of the evidence in the field suggests that the size of the graft in hamstring autograft ACL reconstruction matters when the surgeon is trying to avoid failures. The exact graft diameter needed to avoid failures is not absolutely clear and could depend on other factors, but newer studies suggest than even increases of 0.5 mm up to a graft size of 10 mm are beneficial for the patient. There is still no evidence to recommend the use of grafts > 10 mm. Several methods – e.g. folding the graft in more strands – that are simple and reproducible have been published lately to address the problem of having an insufficient graft size when performing an ACL reconstruction. Due to the evidence presented, we think it is necessary for the surgeon to have them in his or her arsenal before performing an ACL reconstruction. There are obviously other factors that should be considered, especially age. Therefore, a larger graft size should not be taken as the only goal in ACL reconstruction. Cite this article: EFORT Open Rev 2018;3:93-97. DOI: 10.1302/2058-5241.3.170038 PMID:29657850

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.

Traditional herbs: a remedy for cardiovascular disorders.

PubMed

Rastogi, Subha; Pandey, Madan Mohan; Rawat, A K S

2016-10-15

Medicinal plants have been used in patients with congestive heart failure, systolic hypertension, angina pectoris, atherosclerosis, cerebral insufficiency, venous insufficiency and arrhythmia since centuries. A recent increase in the popularity of alternative medicine and natural products has revived interest in traditional remedies that have been used for the treatment of cardiovascular diseases. The purpose of this review is to provide updated, comprehensive and categorized information on the history and traditional uses of some herbal medicines that affect the cardiovascular system in order to explore their therapeutic potential and evaluate future research opportunities. Systematic literature searches were carried out and the available information on various medicinal plants traditionally used for cardiovascular disorders was collected via electronic search (using Pubmed, SciFinder, Scirus, GoogleScholar, JCCC@INSTIRC and Web of Science) and a library search for articles published in peer-reviewed journals. No restrictions regarding the language of publication were imposed. This article highlights the cardiovascular effects of four potent traditional botanicals viz. Garlic (Allium sativum), Guggul (Commiphora wightii), Hawthorn (Crataegus oxyacantha) and Arjuna (Terminalia arjuna). Although these plants have been used in the treatment of heart disease for hundreds of years, current research methods show us they can be utilized effectively in the treatment of cardiovascular diseases including ischemic heart disease, congestive heart failure, arrhythmias and hypertension. Although the mechanisms of action are not very clear, there is enough evidence of their efficacy in various cardiovascular disorders. However, for bringing more objectivity and also to confirm traditional claims, more systematic, well-designed animal and randomized clinical studies with sufficient sample sizes are necessary. Multidisciplinary research is still required to exploit the vast potential of these plants. Potential synergistic and adverse side effects of herb-drug interactions also need to be studied. These approaches will help in establishing them as remedies for cardiovascular diseases and including them in the mainstream of healthcare system. Copyright © 2015 Elsevier GmbH. All rights reserved.

Job satisfaction of registered nurses in a community hospital in the Limpopo Province in South Africa.

PubMed

Kekana, H P P; du Rand, E A; van Wyk, N C

2007-06-01

Nurses are confronted daily with the demands of an increased workload and insufficient facilities in the public healthcare sector in South Africa. The purpose of the study was therefore to determine the degree ofjob satisfaction of registered nurses in a community hospital in the Limpopo Province of South Africa. A quantitative descriptive design was used to meet the objectives of the study. The population was not sampled because of the small size of it. All the registered nurses who had one or more years experience in this hospital were included in the study. A self-administered questionnaire was used to collect data from them regarding the working conditions in the hospital including the emotional and social climate. The questionnaire was based on an instrument developed by Humphries and Turner (1989:303) to determine the degree of job satisfaction of nursing staff in a unit for elderly mentally retarded patients. The findings indicated that the majority of the respondents were dissatisfied about the working conditions and emotional climate in the hospital while they were fairly satisfied with the social climate. The workload and degree of fair remuneration, under the working conditions, were the most highly rated as dissatisfying (83% of the participants) while under the emotional climate they indicated that the pressure under which they worked was highly dissatisfying (82% of the participants). As the results indicated that the social climate was satisfactory; having a best friend at work and the chance to help other people while at work, were rated positively by 88% and 76% of the participants respectively. Recommendations made included that managers have to show the staff that their best interest is their number one concern. Leaders have to be available for the staff and being willing to buffer the stress caused by increased workload and insufficient resources. Greater visibility of supervisory staff should therefore be encouraged.

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.

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.

Geochemistry

NASA Technical Reports Server (NTRS)

Carr, M. H.; Toulmin, P., III

1976-01-01

The most effective strategy for the geochemical study of a planet is to proceed systematically with the mineralogical and chemical characterization of its materials in accordance with geologically determined priorities. It is insufficient merely to analyze chemically the surface rocks. To appreciate the meaning of a chemical analysis, some assessment must be made of the geologic history of the sample - what its source and mode of origin are and what processes have operated upon the sample to cause chemical fractionation. Determination of mineralogy, texture, lithology, and other properties of the rock that might be relevant to origin is, therefore, necessary.

Normally Expected Aberrations in the 8-hour Dynamic EKG

NASA Technical Reports Server (NTRS)

Fleck, R. L.; Arnoldi, L. B.; Townsend, J. C.; Tonesk, X.

1970-01-01

The establishment of norms for interpreting long term dynamic electrocardiograms is attempted by correlating a completely disease symptom and cardiac risk factor free sample with a non-pure sample in the direction of normality on various variables. Out of a population of 362 subjects exposed to dynamic electrocardiogram testing, a discrimination between normals and abnormals in terms of traditional risk factors was observed. The two groups differed significantly on the following variables: cholesterol, smoking, systolic blood pressure, white blood count, fasting blood sugar, uric acid, resting EKG, year of birth, and coronary insufficiency.

A novel method for sampling the suspended sediment load in the tidal environment using bi-directional time-integrated mass-flux sediment (TIMS) samplers

NASA Astrophysics Data System (ADS)

Elliott, Emily A.; Monbureau, Elaine; Walters, Glenn W.; Elliott, Mark A.; McKee, Brent A.; Rodriguez, Antonio B.

2017-12-01

Identifying the source and abundance of sediment transported within tidal creeks is essential for studying the connectivity between coastal watersheds and estuaries. The fine-grained suspended sediment load (SSL) makes up a substantial portion of the total sediment load carried within an estuarine system and efficient sampling of the SSL is critical to our understanding of nutrient and contaminant transport, anthropogenic influence, and the effects of climate. Unfortunately, traditional methods of sampling the SSL, including instantaneous measurements and automatic samplers, can be labor intensive, expensive and often yield insufficient mass for comprehensive geochemical analysis. In estuaries this issue is even more pronounced due to bi-directional tidal flow. This study tests the efficacy of a time-integrated mass sediment sampler (TIMS) design, originally developed for uni-directional flow within the fluvial environment, modified in this work for implementation the tidal environment under bi-directional flow conditions. Our new TIMS design utilizes an 'L' shaped outflow tube to prevent backflow, and when deployed in mirrored pairs, each sampler collects sediment uniquely in one direction of tidal flow. Laboratory flume experiments using dye and particle image velocimetry (PIV) were used to characterize the flow within the sampler, specifically, to quantify the settling velocities and identify stagnation points. Further laboratory tests of sediment indicate that bidirectional TIMS capture up to 96% of incoming SSL across a range of flow velocities (0.3-0.6 m s-1). The modified TIMS design was tested in the field at two distinct sampling locations within the tidal zone. Single-time point suspended sediment samples were collected at high and low tide and compared to time-integrated suspended sediment samples collected by the bi-directional TIMS over the same four-day period. Particle-size composition from the bi-directional TIMS were representative of the array of single time point samples, but yielded greater mass, representative of flow and sediment-concentration conditions at the site throughout the deployment period. This work proves the efficacy of the modified bi-directional TIMS design, offering a novel tool for collection of suspended sediment in the tidally-dominated portion of the watershed.

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

Validation of the Comprehensive ICF Core Set for Vocational Rehabilitation From the Perspective of Physical Therapists: International Delphi Survey.

PubMed

Kaech Moll, Veronika M; Escorpizo, Reuben; Portmann Bergamaschi, Ruth; Finger, Monika E

2016-08-01

The Comprehensive ICF Core Set for vocational rehabilitation (VR) is a list of essential categories on functioning based on the World Health Organization (WHO) International Classification of Functioning, Disability and Health (ICF), which describes a standard for interdisciplinary assessment, documentation, and communication in VR. The aim of this study was to examine the content validity of the Comprehensive ICF Core Set for VR from the perspective of physical therapists. A 3-round email survey was performed using the Delphi method. A convenience sample of international physical therapists working in VR with work experience of ≥2 years were asked to identify aspects they consider as relevant when evaluating or treating clients in VR. Responses were linked to the ICF categories and compared with the Comprehensive ICF Core Set for VR. Sixty-two physical therapists from all 6 WHO world regions responded with 3,917 statements that were subsequently linked to 338 ICF categories. Fifteen (17%) of the 90 categories in the Comprehensive ICF Core Set for VR were confirmed by the physical therapists in the sample. Twenty-two additional ICF categories were identified that were not included in the Comprehensive ICF Core Set for VR. Vocational rehabilitation in physical therapy is not well defined in every country and might have resulted in the small sample size. Therefore, the results cannot be generalized to all physical therapists practicing in VR. The content validity of the ICF Core Set for VR is insufficient from solely a physical therapist perspective. The results of this study could be used to define a physical therapy-specific set of ICF categories to develop and guide physical therapist clinical practice in VR. © 2016 American Physical Therapy Association.

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.

A statistical assessment of pesticide pollution in surface waters using environmental monitoring data: Chlorpyrifos in Central Valley, California.

PubMed

Wang, Dan; Singhasemanon, Nan; Goh, Kean S

2016-11-15

Pesticides are routinely monitored in surface waters and resultant data are analyzed to assess whether their uses will damage aquatic eco-systems. However, the utility of the monitoring data is limited because of the insufficiency in the temporal and spatial sampling coverage and the inability to detect and quantify trace concentrations. This study developed a novel assessment procedure that addresses those limitations by combining 1) statistical methods capable of extracting information from concentrations below changing detection limits, 2) statistical resampling techniques that account for uncertainties rooted in the non-detects and insufficient/irregular sampling coverage, and 3) multiple lines of evidence that improve confidence in the final conclusion. This procedure was demonstrated by an assessment on chlorpyrifos monitoring data in surface waters of California's Central Valley (2005-2013). We detected a significant downward trend in the concentrations, which cannot be observed by commonly-used statistical approaches. We assessed that the aquatic risk was low using a probabilistic method that works with non-detects and has the ability to differentiate indicator groups with varying sensitivity. In addition, we showed that the frequency of exceedance over ambient aquatic life water quality criteria was affected by pesticide use, precipitation and irrigation demand in certain periods anteceding the water sampling events. Copyright © 2016 Elsevier B.V. All rights reserved.

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

Nutritional status and dietary intakes of children aged 6 months to 12 years: findings of the Nutrition Survey of Malaysian Children (SEANUTS Malaysia).

PubMed

Poh, Bee Koon; Ng, Boon Koon; Siti Haslinda, Mohd Din; Nik Shanita, Safii; Wong, Jyh Eiin; Budin, Siti Balkis; Ruzita, Abd Talib; Ng, Lai Oon; Khouw, Ilse; Norimah, A Karim

2013-09-01

The dual burden of malnutrition reportedly coexists in Malaysia; however, existing data are scarce and do not adequately represent the nutritional status of Malaysian children. The Nutrition Survey of Malaysian Children was carried out with the aim of assessing the nutritional status in a sample of nationally representative population of children aged 6 months to 12 years. A total of 3542 children were recruited using a stratified random sampling method. Anthropometric measurements included weight, height, mid-upper arm circumference, and waist and hip circumferences. Blood biochemical assessment involved analyses of Hb, serum ferritin, and vitamins A and D. Dietary intake was assessed using semi-quantitative FFQ, and nutrient intakes were compared with the Malaysian Recommended Nutrient Intakes (RNI). The prevalence of overweight (9·8%) and obesity (11·8%) was higher than that of thinness (5·4%) and stunting (8·4%). Only a small proportion of children had low levels of Hb (6·6%), serum ferritin (4·4%) and vitamin A (4·4%), but almost half the children (47·5%) had vitamin D insufficiency. Dietary intake of the children was not compatible with the recommendations, where more than one-third did not achieve the Malaysian RNI for energy, Ca and vitamin D. The present study revealed that overnutrition was more prevalent than undernutrition. The presence of high prevalence of vitamin D insufficiency and the inadequate intake of Ca and vitamin D are of concern. Hence, strategies for improving the nutritional status of Malaysian children need to consider both sides of malnutrition and also put emphasis on approaches for the prevention of overweight and obesity as well as vitamin D insufficiency.

Contribution of Individual and Environmental Factors to Physical Activity Level among Spanish Adults

PubMed Central

Serrano-Sanchez, José Antonio; Lera-Navarro, Angela; Dorado-García, Cecilia; González-Henriquez, Juan José; Sanchis-Moysi, Joaquin

2012-01-01

Background Lack of physical activity (PA) is a major risk for chronic disease and obesity. The main aims of the present study were to identify individual and environmental factors independently associated with PA and examine the relative contribution of these factors to PA level in Spanish adults. Methodology/Principal Findings A population-based cross-sectional sample of 3,000 adults (18–75 years old) from Gran Canaria (Spain) was selected using a multistage stratified random sampling method. The participants were interviewed at home using a validated questionnaire to assess PA as well as individual and environmental factors. The data were analyzed using bivariate and multivariate logistic regression. One demographic variable (education), two cognitive (self-efficacy and perceived barriers), and one social environmental (organized format) were independently associated with PA in both genders. Odds ratios ranged between 1.76–2.07 in men and 1.35–2.50 in women (both p<0.05). Individual and environmental factors explained about one-third of the variance in PA level. Conclusions/Significance Self-efficacy and perceived barriers were the most significant factors to meet an adequate level of PA. The risk of insufficient PA was twofold greater in men with primary or lesser studies and who are employed. In women, living in rural environments increased the risk of insufficient PA. The promotion of organized PA may be an efficient way to increase the level of PA in the general population. Improvement in the access to sport facilities and places for PA is a prerequisite that may be insufficient and should be combined with strategies to improve self-efficacy and overcome perceived barriers in adulthood. PMID:22685598

Iodine status in pregnancy and household salt iodine content in rural Bangladesh.

PubMed

Shamim, Abu Ahmed; Christian, Parul; Schulze, Kerry J; Ali, Hasmot; Kabir, Alamgir; Rashid, Mahbubur; Labrique, Alain; Salamatullah, Qauzi; West, Keith P

2012-04-01

Adequate maternal iodine intake is essential during pregnancy for the development of the foetus. To assess the extent of iodine insufficiency and its association with household iodized salt in rural Bangladesh, we measured urinary iodine and household salt iodine content among pregnant women in early (≤16 weeks, n = 1376) and late (≥32 weeks, n = 1114) pregnancy. Salt (∼20 g) and a spot urine sample (∼10 mL) were collected from women participating in a randomized, placebo-controlled trial of vitamin A or beta-carotene supplementation in rural northwestern Bangladesh during home visits in early and late pregnancy. Salt iodine was analyzed by iodometric titration, and urinary iodine by the Ohashi method. Almost all salt samples had some detectable iodine, but over 75% contained <15 ppm. Median (interquartile range) urinary iodine concentrations were 66 (34-133) and 55 (28-110) µg L⁻¹ in early and late pregnancy, respectively; urinary iodine <150 µg L⁻¹ was found in ∼80% of women at both times in pregnancy. Although the risk of iodine insufficiency declined with increasing iodine content of household salt (P for trend <0.05), median urinary iodine did not reach 150 µg L⁻¹ until iodine in household salt was at least 32 ppm and 51 ppm during early and late pregnancy, respectively. Despite a national policy on universal salt iodization, salt iodine content remains insufficient to maintain adequate maternal iodine status throughout pregnancy in rural northern Bangladesh. Alternative measures like direct iodine supplementation during pregnancy could be considered to assure adequate iodine status during this high-risk period of life. © 2010 Blackwell Publishing Ltd.

Vitamin D Levels and Markers of Inflammation and Metabolism in HIV-Infected Individuals on Suppressive Antiretroviral Therapy.

PubMed

Hoffman, Risa M; Lake, Jordan E; Wilhalme, Holly M; Tseng, Chi-Hong; Currier, Judith S

2016-03-01

Data on vitamin D insufficiency as a cause of inflammation and metabolic dysfunction in HIV-infected individuals are conflicting. We examined the relationships between levels of 25-hydroxyvitamin D [25(OH)D] and biomarkers of inflammation and metabolism in stored blood samples from a prospective trial of vitamin D repletion. Blood samples from HIV-infected individuals on antiretroviral therapy (ART) with HIV-1 RNA <200 copies/ml enrolled in a prospective study were analyzed for 25(OH)D levels, a broad panel of cytokines, highly sensitive C-reactive protein, D-dimer, adiponectin, leptin, and insulin. Correlations between markers and 25(OH)D levels were determined. The Wilcoxon Rank Sum test was used to compare markers between individuals 25(OH)D insufficient and sufficient at baseline and before and after repletion among those who were insufficient and repleted to ≥30 ng/ml after 12 weeks. Of 106 subjects with stored plasma [66 with 25(OH)D <30 ng/ml and 40 ≥ 30 ng/ml], the median age was 50, the CD4 count was 515 cells/mm(3), 94% were male, and the median baseline 25(OH)D was 27 ng/ml. Higher 25(OH)D levels were associated with lower tumor necrosis factor (TNF)-α (r = -0.20, p = 0.04) and higher adiponectin levels (r = 0.30, p = 0.002). Following successful repletion to 25(OH)D ≥30 ng/ml there were no significant changes in inflammatory or metabolic parameters. Our study found associations between low 25(OH)D levels and TNF-α and adiponectin. Repletion did not result in changes in markers of inflammation or metabolism. These data support continued study of the relationship between vitamin D, inflammation, and metabolism in treated HIV infection.

The role of mHealth for improving medication adherence in patients with cardiovascular disease: a systematic review.

PubMed

Gandapur, Yousuf; Kianoush, Sina; Kelli, Heval M; Misra, Satish; Urrea, Bruno; Blaha, Michael J; Graham, Garth; Marvel, Francoise A; Martin, Seth S

2016-10-01

Cardiovascular disease is a leading cause of morbidity and mortality worldwide, and a key barrier to improved outcomes is medication non-adherence. The aim of this study is to review the role of mobile health (mHealth) tools for improving medication adherence in patients with cardiovascular disease. We performed a systematic search for randomized controlled trials that primarily investigated mHealth tools for improving adherence to cardiovascular disease medications in patients with hypertension, coronary artery disease, heart failure, peripheral arterial disease, and stroke. We extracted and reviewed data on the types of mHealth tools used, preferences of patients and healthcare providers, the effect of the mHealth interventions on medication adherence, and the limitations of trials. We identified 10 completed trials matching our selection criteria, mostly with <100 participants, and ranging in duration from 1 to 18 months. mHealth tools included text messages, Bluetooth-enabled electronic pill boxes, online messaging platforms, and interactive voice calls. Patients and healthcare providers generally preferred mHealth to other interventions. All 10 studies reported that mHealth interventions improved medication adherence, though the magnitude of benefit was not consistently large and in one study was not greater than a telehealth comparator. Limitations of trials included small sample sizes, short duration of follow-up, self-reported outcomes, and insufficient assessment of unintended harms and financial implications. Current evidence suggests that mHealth tools can improve medication adherence in patients with cardiovascular diseases. However, high-quality clinical trials of sufficient size and duration are needed to move the field forward and justify use in routine care.

Quantitative and qualitative analysis of semantic verbal fluency in patients with temporal lobe epilepsy.

PubMed

Jaimes-Bautista, A G; Rodríguez-Camacho, M; Martínez-Juárez, I E; Rodríguez-Agudelo, Y

2017-08-29

Patients with temporal lobe epilepsy (TLE) perform poorly on semantic verbal fluency (SVF) tasks. Completing these tasks successfully involves multiple cognitive processes simultaneously. Therefore, quantitative analysis of SVF (number of correct words in one minute), conducted in most studies, has been found to be insufficient to identify cognitive dysfunction underlying SVF difficulties in TLE. To determine whether a sample of patients with TLE had SVF difficulties compared with a control group (CG), and to identify the cognitive components associated with SVF difficulties using quantitative and qualitative analysis. SVF was evaluated in 25 patients with TLE and 24 healthy controls; the semantic verbal fluency test included 5 semantic categories: animals, fruits, occupations, countries, and verbs. All 5 categories were analysed quantitatively (number of correct words per minute and interval of execution: 0-15, 16-30, 31-45, and 46-60seconds); the categories animals and fruits were also analysed qualitatively (clusters, cluster size, switches, perseverations, and intrusions). Patients generated fewer words for all categories and intervals and fewer clusters and switches for animals and fruits than the CG (P<.01). Differences between groups were not significant in terms of cluster size and number of intrusions and perseverations (P>.05). Our results suggest an association between SVF difficulties in TLE and difficulty activating semantic networks, impaired strategic search, and poor cognitive flexibility. Attention, inhibition, and working memory are preserved in these patients. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Characterization of infectious aerosols in health care facilities: an aid to effective engineering controls and preventive strategies.

PubMed

Cole, E C; Cook, C E

1998-08-01

Assessment of strategies for engineering controls for the prevention of airborne infectious disease transmission to patients and to health care and related workers requires consideration of the factors relevant to aerosol characterization. These factors include aerosol generation, particle size and concentrations, organism viability, infectivity and virulence, airflow and climate, and environmental sampling and analysis. The major focus on attention to engineering controls comes from recent increases in tuberculosis, particularly the multidrug-resistant varieties in the general hospital population, the severely immunocompromised, and those in at-risk and confined environments such as prisons, long-term care facilities, and shelters for the homeless. Many workers are in close contact with persons who have active, undiagnosed, or insufficiently treated tuberculosis. Additionally, patients and health care workers may be exposed to a variety of pathogenic human viruses, opportunistic fungi, and bacteria. This report therefore focuses on the nature of infectious aerosol transmission in an attempt to determine which factors can be systematically addressed to result in proven, applied engineering approaches to the control of infectious aerosols in hospital and health care facility environments. The infectious aerosols of consideration are those that are generated as particles of respirable size by both human and environmental sources and that have the capability of remaining viable and airborne for extended periods in the indoor environment. This definition precludes skin and mucous membrane exposures occurring from splashes (rather than true aerosols) of blood or body fluids containing infectious disease agents. There are no epidemiologic or laboratory studies documenting the transmission of bloodborne virus by way of aerosols.

An analysis of the orbital distribution of solid rocket motor slag

NASA Astrophysics Data System (ADS)

Horstman, Matthew F.; Mulrooney, Mark

2009-01-01

The contribution by solid rocket motors (SRMs) to the orbital debris environment is potentially significant and insufficiently studied. Design and combustion processes can lead to the emission of enough by-products to warrant assessment of their contribution to orbital debris. These particles are formed during SRM tail-off, or burn termination, by the rapid solidification of molten Al2O3 slag accumulated during the burn. The propensity of SRMs to generate particles larger than 100μm raises concerns regarding the debris environment. Sizes as large as 1 cm have been witnessed in ground tests, and comparable sizes have been estimated via observations of sub-orbital tail-off events. Utilizing previous research we have developed more sophisticated size distributions and modeled the time evolution of resultant orbital populations using a historical database of SRM launches, propellant, and likely location and time of tail-off. This analysis indicates that SRM ejecta is a significant component of the debris environment.

Vitamin D status and antimicrobial peptide cathelicidin (LL-37) concentrations in patients with active pulmonary tuberculosis.

PubMed

Yamshchikov, Alexandra V; Kurbatova, Ekaterina V; Kumari, Meena; Blumberg, Henry M; Ziegler, Thomas R; Ray, Susan M; Tangpricha, Vin

2010-09-01

Vitamin D insufficiency is common in industrialized and developing nations. Recent studies have shown that vitamin D insufficiency is associated with a higher risk of active tuberculosis. Laboratory studies provided a mechanism for this link on the basis of findings that vitamin D metabolites regulate the expression of cathelicidin (LL-37), which is an endogenous antimicrobial peptide with activity against Mycobacterium tuberculosis. Little information is available on the clinical relation between vitamin D, LL-37 concentrations, and disease severity in patients with tuberculosis. The primary objective of the study was to evaluate the relation between vitamin D nutriture, serum LL-37 concentrations, and tuberculosis by using samples stored in the Tuberculosis Trials Consortium serum repository. We measured 25-hydroxyvitamin D [25(OH)D] and LL-37 concentrations in 95 serum specimens from patients with culture-confirmed pulmonary tuberculosis and correlated these concentrations to clinical and demographic variables. The prevalence of vitamin D insufficiency [serum 25(OH)D concentration lt 30 ng/mL] in patients with active tuberculosis was 86% (n = 95) with a mean baseline serum 25(OH)D concentration of 20.4 ng/mL. Factors associated with vitamin D insufficiency were black race and indoor lifestyle. The mean ( plusmn SD) baseline LL-37 concentration was 49.5 plusmn 23.8 ng/mL. Higher LL-37 concentrations correlated with acid fast bacilli sputum smear positivity and weight gt 10% below ideal body weight. Serum vitamin D status of the study subjects did not correlate with serum LL-37 concentrations. More prospectively designed studies are needed to evaluate the clinical implications of vitamin D insufficiency in patients with tuberculosis and the utility of circulating LL-37 as a potential biomarker in patients with active tuberculosis disease. The parent trial was registered at clinicaltrials.gov as NCT00023335.

Maternal and paternal sleep during pregnancy in the Child-sleep birth cohort.

PubMed

Juulia Paavonen, E; Saarenpää-Heikkilä, Outi; Pölkki, Pirjo; Kylliäinen, Anneli; Porkka-Heiskanen, Tarja; Paunio, Tiina

2017-01-01

Maternal and paternal sleep insufficiency during pregnancy appears to be a risk factor for health and wellbeing in young families. Here, we evaluated the prevalence of sleep insufficiency and symptoms of insomnia during pregnancy (at 32nd pregnancy week) and their relationship to depression, anxiety and environmental stress. The study is based on a population based sample from Finland consisting of 1667 mothers and 1498 fathers from the Child-sleep birth cohort. We evaluated both the core symptoms of insomnia (sleep onset problems, nocturnal awakenings, too-early awakenings, and poor sleep quality) and the presence of insufficient sleep. Insufficient sleep was defined as a two-hour difference between self-assessed sleep need and reported sleep duration, or sleep duration shorter than six hours per night. We found that symptoms of insomnia were more prevalent among women than among men (9.8% vs. 6.2%), whereas sleep debt was less prevalent among women than among men (4.5% vs. 9.6%). Overall, 11.8% of the women and 14.9% of the men reported either significant insomnia or short sleep. Symptoms of insomnia were related to symptoms of depression both among women and men (AOR 3.8, 95% CI 2.6-5.6 vs. AOR 1.9, 95% CI 1.1-3.2), while short sleep was related to depression among women (AOR 3.3, 95% CI 1.8-5.8), and to low education, poor health and a larger number of children among men. The study showed that insomnia and sleep insufficiency are prevalent among women and men during pregnancy. The findings underline the impact of insomnia to both maternal and paternal health during pregnancy as well as to the implementation of effective interventions to prevent negative consequences of sleep disturbances. Copyright © 2016. Published by Elsevier B.V.

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.

Electromagnetic Scattering by Fully Ordered and Quasi-Random Rigid Particulate Samples

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.; Dlugach, Janna M.; Mackowski, Daniel W.

2016-01-01

In this paper we have analyzed circumstances under which a rigid particulate sample can behave optically as a true discrete random medium consisting of particles randomly moving relative to each other during measurement. To this end, we applied the numerically exact superposition T-matrix method to model far-field scattering characteristics of fully ordered and quasi-randomly arranged rigid multiparticle groups in fixed and random orientations. We have shown that, in and of itself, averaging optical observables over movements of a rigid sample as a whole is insufficient unless it is combined with a quasi-random arrangement of the constituent particles in the sample. Otherwise, certain scattering effects typical of discrete random media (including some manifestations of coherent backscattering) may not be accurately replicated.

Autonomous spatially adaptive sampling in experiments based on curvature, statistical error and sample spacing with applications in LDA measurements

NASA Astrophysics Data System (ADS)

Theunissen, Raf; Kadosh, Jesse S.; Allen, Christian B.

2015-06-01

Spatially varying signals are typically sampled by collecting uniformly spaced samples irrespective of the signal content. For signals with inhomogeneous information content, this leads to unnecessarily dense sampling in regions of low interest or insufficient sample density at important features, or both. A new adaptive sampling technique is presented directing sample collection in proportion to local information content, capturing adequately the short-period features while sparsely sampling less dynamic regions. The proposed method incorporates a data-adapted sampling strategy on the basis of signal curvature, sample space-filling, variable experimental uncertainty and iterative improvement. Numerical assessment has indicated a reduction in the number of samples required to achieve a predefined uncertainty level overall while improving local accuracy for important features. The potential of the proposed method has been further demonstrated on the basis of Laser Doppler Anemometry experiments examining the wake behind a NACA0012 airfoil and the boundary layer characterisation of a flat plate.

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.

Quality of compounded hydrocortisone capsules used in the treatment of children.

PubMed

Neumann, Uta; Burau, Daniela; Spielmann, Sarah; Whitaker, Martin J; Ross, Richard J; Kloft, Charlotte; Blankenstein, Oliver

2017-08-01

Due to the lack of paediatric-licensed formulations, children are often treated with individualized pharmacy-compounded adult medication. An international web-based survey about the types of medication in children with adrenal insufficiency (AI) revealed that the majority of paediatric physicians are using pharmacy-compounded medication to treat children with AI. Observations of loss of therapy control in children with congenital adrenal hyperplasia with compounded hydrocortisone capsules and regained control after prescribing a new hydrocortisone batch led to this 'real world' evaluation of pharmacy-compounded paediatric hydrocortisone capsules. Capsule samples were collected randomly from volunteering parents of treated children suffering from congenital adrenal hyperplasia from all over Germany. Analysis of net mass and hydrocortisone content by high-performance liquid chromatography with ultraviolet (HPLC-UV) detection method was performed based on the European Pharmacopeia. In a total of 61 batches that were sent, 5 batches could not be analysed because of missing dose information, insufficient number of capsules or were not possible to be evaluated. Fifty-six batches containing 1125 capsules were evaluated. 21.4% of the batches revealed insufficiency in uniformity of net mass or drug content and additional 3.6% failed because they did not contain the labelled drug. Compounded medication is a possible cause of variation of steroid doses in children with adrenal insufficiency or congenital adrenal hyperplasia, putting these vulnerable patients at risk of poor disease control and adrenal crisis. These data may apply to other individualized compounded oral medication as well, emphasizing the need for development of licensed paediatric formulations approved by regulatory authorities. © 2017 European Society of Endocrinology.

Effect of multi-nutrient insufficiency on markers of one carbon metabolism in young women: response to a methionine load.

PubMed

Katre, P; Joshi, S; Bhat, D S; Deshmukh, M; Gurav, N; Pandit, S; Lubree, H; Marczewski, S; Bennett, C; Gruca, L; Kalyanaraman, K; Naik, S S; Yajnik, C S; Kalhan, S C

2016-06-01

Multi-nutrient insufficiencies as a consequence of nutritional and economic factors are common in India and other developing countries. We have examined the impact of multi-nutrient insufficiency on markers of one carbon (1C) metabolism in the blood, and response to a methionine load in clinically healthy young women. Young women from Pune, India (n=10) and Cleveland, USA (n=13) were studied. Blood samples were obtained in the basal state and following an oral methionine load (50 mg/kg of body weight in orange juice). Plasma concentrations of vitamin B12, folate and B6 were measured in the basal state. The effect of methionine load on the levels of methionine, total homocysteine, cysteine, glutathione and amino acids was examined. Indian women were significantly shorter and lighter compared with the American women and had lower plasma concentration of vitamins B12, folate and B6, essential amino acids and glutathione, but higher concentration of total homocysteine. The homocysteine response to methionine load was higher in Indian women. The plasma concentrations of glycine and serine increased in the Indian women after methionine (in juice) load. A significant negative correlation between plasma B6 and homocysteine (r= -0.70), and plasma folate and glycine and serine levels were observed in the Indian group (P<0.05) but not in the American group. Multi-nutrient insufficiency in the Indian women caused unique changes in markers of whole body protein and 1C metabolism. These data would be useful in developing nutrient intervention strategies.

Using genetic algorithms to optimize k-Nearest Neighbors configurations for use with airborne laser scanning data

Treesearch

Ronald E. McRoberts; Grant M. Domke; Qi Chen; Erik Næsset; Terje Gobakken

2016-01-01

The relatively small sampling intensities used by national forest inventories are often insufficient to produce the desired precision for estimates of population parameters unless the estimation process is augmented with auxiliary information, usually in the form of remotely sensed data. The k-Nearest Neighbors (k-NN) technique is a non-parametric,multivariate approach...

Social Work Faculty's Knowledge of Aging: Results from a National Sample

ERIC Educational Resources Information Center

Wang, Donna S.; Chonody, Jill M.; Krase, Kathryn

2013-01-01

Social work students have reported in previous studies that they receive insufficient coursework and training to work effectively with older adults. A critical factor in these deficiencies may be the level of knowledge of social work faculty. This study sought to assess social work faculty's knowledge of aging using the Knowledge of Aging for…

Identifying Gifted Students in Puerto Rico: Validation of a Spanish Translation of the Gifted Rating Scales

ERIC Educational Resources Information Center

Rosado, Javier I.; Pfeiffer, Steven; Petscher, Yaacov

2015-01-01

The challenge of correctly identifying gifted students is a critical issue. Gifted education in Puerto Rico is marked by insufficient support and a lack of appropriate identification methods. This study examined the reliability and validity of a Spanish translation of the "Gifted Rating Scales-School Form" (GRS) with a sample of 618…

Prevalence and Determinants of Suboptimal Vitamin D Levels in a Multiethnic Asian Population.

PubMed

Man, Ryan Eyn Kidd; Li, Ling-Jun; Cheng, Ching-Yu; Wong, Tien Yin; Lamoureux, Ecosse; Sabanayagam, Charumathi

2017-03-22

This population-based cross-sectional study examined the prevalence and risk factors of suboptimal vitamin D levels (assessed using circulating 25-hydroxycholecalciferol (25(OH)D)) in a multi-ethnic sample of Asian adults. Plasma 25(OH)D concentration of 1139 Chinese, Malay and Indians (40-80 years) were stratified into normal (≥30 ng/mL), and suboptimal (including insufficiency and deficiency, <30 ng/mL) based on the 2011 Endocrine Society Clinical Practice Guidelines. Logistic regression models were used to assess the associations of demographic, lifestyle and clinical risk factors with the outcome. Of the 1139 participants, 25(OH)D concentration was suboptimal in 76.1%. In multivariable models, age ≤65 years (compared to age >65 years), Malay and Indian ethnicities (compared to Chinese ethnicity), and higher body mass index, HbA1c, education and income levels were associated with suboptimal 25(OH)D concentration ( p < 0.05). In a population-based sample of Asian adults, approximately 75% had suboptimal 25(OH)D concentration. Targeted interventions and stricter reinforcements of existing guidelines for vitamin D supplementation are needed for groups at risk of vitamin D insufficiency/deficiency.

Weekend catch-up sleep is independently associated with suicide attempts and self-injury in Korean adolescents.

PubMed

Kang, Seung-Gul; Lee, Yu Jin; Kim, Seog Ju; Lim, Weonjeong; Lee, Heon-Jeong; Park, Young-Min; Cho, In Hee; Cho, Seong-Jin; Hong, Jin Pyo

2014-02-01

The current study aims to determine the associations of insufficient sleep with suicide attempts and self-injury in a large, school-based Korean adolescent sample. A sample of 4553 middle- and high-school students (grades 7-10) was recruited in this study. Finally, 4145 students completed self-report questionnaires including items on sleep duration (weekday/weekend), self-injury, suicide attempts during the past year, the Suicidal Ideation Questionnaire (SIQ), and the Beck Depression Inventory (BDI). A multiple linear regression model showed that higher SIQ scores were associated with longer weekend catch-up sleep duration (p=0.009), higher BDI score (p<0.001), and longer time spent in a private educational institute (p=0.025). The multiple logistic regression analysis revealed that longer weekend catch-up sleep duration (p=0.011), higher BDI score (p<0.001), longer time spent in a private educational institute (p=0.046), and poorer academic record (p=0.029) were associated with suicide attempt and self-injury during the past year. The present results suggest that weekend catch-up sleep duration--which is an indicator of insufficient weekday sleep--might be associated with suicide attempts and self-injury in Korean adolescents. © 2014.

Comparison of sampling methods to measure HIV RNA viral load in female genital tract secretions.

PubMed

Jaumdally, Shameem Z; Jones, Heidi E; Hoover, Donald R; Gamieldien, Hoyam; Kriek, Jean-Mari; Langwenya, Nontokozo; Myer, Landon; Passmore, Jo-Ann S; Todd, Catherine S

2017-03-01

How does menstrual cup (MC) compare to other genital sampling methods for HIV RNA recovery? We compared HIV RNA levels between MC, endocervical swab (ECS), and ECS-enriched cervicovaginal lavage (eCVL) specimens in 51 HIV-positive, antiretroviral therapy-naive women at enrollment, 3 and 6 months, with order rotated by visit. Paired comparisons were analyzed with McNemar's exact tests, signed-rank tests, and an extension of Somer's D for pooled analyses across visits. MC specimens had the highest proportion of quantifiable HIV VL at enrollment and month 3, but more MC specimens (n=12.8%) were insufficient for testing, compared with ECS (2%, P=0.006) and eCVL (0%, P<0.001). Among sufficient specimens, median VL was significantly higher for MC (2.62 log 10 copies/mL) compared to ECS (1.30 log 10 copies/mL, P<0.001) and eCVL (1.60 log 10 copies/mL, P<0.001) across visits. MC may be more sensitive than eCVL and CVS, provided insufficient specimens are reduced. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Prevalence and Determinants of Suboptimal Vitamin D Levels in a Multiethnic Asian Population

PubMed Central

Man, Ryan Eyn Kidd; Li, Ling-Jun; Cheng, Ching-Yu; Wong, Tien Yin; Lamoureux, Ecosse; Sabanayagam, Charumathi

2017-01-01

This population-based cross-sectional study examined the prevalence and risk factors of suboptimal vitamin D levels (assessed using circulating 25-hydroxycholecalciferol (25(OH)D)) in a multi-ethnic sample of Asian adults. Plasma 25(OH)D concentration of 1139 Chinese, Malay and Indians (40–80 years) were stratified into normal (≥30 ng/mL), and suboptimal (including insufficiency and deficiency, <30 ng/mL) based on the 2011 Endocrine Society Clinical Practice Guidelines. Logistic regression models were used to assess the associations of demographic, lifestyle and clinical risk factors with the outcome. Of the 1139 participants, 25(OH)D concentration was suboptimal in 76.1%. In multivariable models, age ≤65 years (compared to age >65 years), Malay and Indian ethnicities (compared to Chinese ethnicity), and higher body mass index, HbA1c, education and income levels were associated with suboptimal 25(OH)D concentration (p < 0.05). In a population-based sample of Asian adults, approximately 75% had suboptimal 25(OH)D concentration. Targeted interventions and stricter reinforcements of existing guidelines for vitamin D supplementation are needed for groups at risk of vitamin D insufficiency/deficiency. PMID:28327512

Characteristics of insufficiently active participants that benefit from health-enhancing physical activity (HEPA) promotion programs implemented in the sports club setting.

PubMed

Ooms, Linda; Leemrijse, Chantal; Collard, Dorine; Schipper-van Veldhoven, Nicolette; Veenhof, Cindy

2018-06-01

Health-enhancing physical activity (HEPA) promotion programs are implemented in sports clubs. The purpose of this study was to examine the characteristics of the insufficiently active participants that benefit from these programs. Data of three sporting programs, developed for insufficiently active adults, were used for this study. These sporting programs were implemented in different sports clubs in the Netherlands. Participants completed an online questionnaire at baseline and after six months (n = 458). Of this sample, 35.1% (n = 161) was insufficiently active (i.e. not meeting HEPA levels) at baseline. Accordingly, two groups were compared: participants who were insufficiently active at baseline, but increased their physical activity to HEPA levels after six months (activated group, n = 86) versus participants who were insufficiently active both at baseline and after six months (non-activated group, n = 75). Potential associated characteristics (demographic, social, sport history, physical activity) were included as independent variables in bivariate and multivariate logistic regression analyses. The percentage of active participants increased significantly from baseline to six months (from 64.9 to 76.9%, p < 0.05). The bivariate logistic regression analyses showed that participants in the activated group were more likely to receive support from family members with regard to their sport participation (62.8% vs. 42.7%, p = 0.02) and spent more time in moderate-intensity physical activity (128 ± 191 min/week vs. 70 ± 106 min/week, p = 0.02) at baseline compared with participants in the non-activated group. These results were confirmed in the multivariate logistic regression analyses: when receiving support from most family members, there is a 216% increase in the odds of being in the activated group (OR = 2.155; 95% CI: 1.118-4.154, p = 0.02) and for each additional 1 min/week spent in moderate-intensity physical activity, the odds increases with 0.3% (OR = 1.003; 95% CI: 1.001-1.006, p = 0.02). The results suggest that HEPA sporting programs can be used to increase HEPA levels of insufficiently active people, but it seems a challenge to reach the least active ones. It is important that promotional strategies and channels are tailored to the target group. Furthermore, strategies that promote family support may enhance the impact of the programs.

Sample size and power calculations for detecting changes in malaria transmission using antibody seroconversion rate.

PubMed

Sepúlveda, Nuno; Paulino, Carlos Daniel; Drakeley, Chris

2015-12-30

Several studies have highlighted the use of serological data in detecting a reduction in malaria transmission intensity. These studies have typically used serology as an adjunct measure and no formal examination of sample size calculations for this approach has been conducted. A sample size calculator is proposed for cross-sectional surveys using data simulation from a reverse catalytic model assuming a reduction in seroconversion rate (SCR) at a given change point before sampling. This calculator is based on logistic approximations for the underlying power curves to detect a reduction in SCR in relation to the hypothesis of a stable SCR for the same data. Sample sizes are illustrated for a hypothetical cross-sectional survey from an African population assuming a known or unknown change point. Overall, data simulation demonstrates that power is strongly affected by assuming a known or unknown change point. Small sample sizes are sufficient to detect strong reductions in SCR, but invariantly lead to poor precision of estimates for current SCR. In this situation, sample size is better determined by controlling the precision of SCR estimates. Conversely larger sample sizes are required for detecting more subtle reductions in malaria transmission but those invariantly increase precision whilst reducing putative estimation bias. The proposed sample size calculator, although based on data simulation, shows promise of being easily applicable to a range of populations and survey types. Since the change point is a major source of uncertainty, obtaining or assuming prior information about this parameter might reduce both the sample size and the chance of generating biased SCR estimates.

Small sample sizes in the study of ontogenetic allometry; implications for palaeobiology

PubMed Central

Vavrek, Matthew J.

2015-01-01

Quantitative morphometric analyses, particularly ontogenetic allometry, are common methods used in quantifying shape, and changes therein, in both extinct and extant organisms. Due to incompleteness and the potential for restricted sample sizes in the fossil record, palaeobiological analyses of allometry may encounter higher rates of error. Differences in sample size between fossil and extant studies and any resulting effects on allometric analyses have not been thoroughly investigated, and a logical lower threshold to sample size is not clear. Here we show that studies based on fossil datasets have smaller sample sizes than those based on extant taxa. A similar pattern between vertebrates and invertebrates indicates this is not a problem unique to either group, but common to both. We investigate the relationship between sample size, ontogenetic allometric relationship and statistical power using an empirical dataset of skull measurements of modern Alligator mississippiensis. Across a variety of subsampling techniques, used to simulate different taphonomic and/or sampling effects, smaller sample sizes gave less reliable and more variable results, often with the result that allometric relationships will go undetected due to Type II error (failure to reject the null hypothesis). This may result in a false impression of fewer instances of positive/negative allometric growth in fossils compared to living organisms. These limitations are not restricted to fossil data and are equally applicable to allometric analyses of rare extant taxa. No mathematically derived minimum sample size for ontogenetic allometric studies is found; rather results of isometry (but not necessarily allometry) should not be viewed with confidence at small sample sizes. PMID:25780770

Improving the accuracy of livestock distribution estimates through spatial interpolation.

PubMed

Bryssinckx, Ward; Ducheyne, Els; Muhwezi, Bernard; Godfrey, Sunday; Mintiens, Koen; Leirs, Herwig; Hendrickx, Guy

2012-11-01

Animal distribution maps serve many purposes such as estimating transmission risk of zoonotic pathogens to both animals and humans. The reliability and usability of such maps is highly dependent on the quality of the input data. However, decisions on how to perform livestock surveys are often based on previous work without considering possible consequences. A better understanding of the impact of using different sample designs and processing steps on the accuracy of livestock distribution estimates was acquired through iterative experiments using detailed survey. The importance of sample size, sample design and aggregation is demonstrated and spatial interpolation is presented as a potential way to improve cattle number estimates. As expected, results show that an increasing sample size increased the precision of cattle number estimates but these improvements were mainly seen when the initial sample size was relatively low (e.g. a median relative error decrease of 0.04% per sampled parish for sample sizes below 500 parishes). For higher sample sizes, the added value of further increasing the number of samples declined rapidly (e.g. a median relative error decrease of 0.01% per sampled parish for sample sizes above 500 parishes. When a two-stage stratified sample design was applied to yield more evenly distributed samples, accuracy levels were higher for low sample densities and stabilised at lower sample sizes compared to one-stage stratified sampling. Aggregating the resulting cattle number estimates yielded significantly more accurate results because of averaging under- and over-estimates (e.g. when aggregating cattle number estimates from subcounty to district level, P <0.009 based on a sample of 2,077 parishes using one-stage stratified samples). During aggregation, area-weighted mean values were assigned to higher administrative unit levels. However, when this step is preceded by a spatial interpolation to fill in missing values in non-sampled areas, accuracy is improved remarkably. This counts especially for low sample sizes and spatially even distributed samples (e.g. P <0.001 for a sample of 170 parishes using one-stage stratified sampling and aggregation on district level). Whether the same observations apply on a lower spatial scale should be further investigated.

Biostatistics Series Module 5: Determining Sample Size

PubMed Central

Hazra, Avijit; Gogtay, Nithya

2016-01-01

Determining the appropriate sample size for a study, whatever be its type, is a fundamental aspect of biomedical research. An adequate sample ensures that the study will yield reliable information, regardless of whether the data ultimately suggests a clinically important difference between the interventions or elements being studied. The probability of Type 1 and Type 2 errors, the expected variance in the sample and the effect size are the essential determinants of sample size in interventional studies. Any method for deriving a conclusion from experimental data carries with it some risk of drawing a false conclusion. Two types of false conclusion may occur, called Type 1 and Type 2 errors, whose probabilities are denoted by the symbols σ and β. A Type 1 error occurs when one concludes that a difference exists between the groups being compared when, in reality, it does not. This is akin to a false positive result. A Type 2 error occurs when one concludes that difference does not exist when, in reality, a difference does exist, and it is equal to or larger than the effect size defined by the alternative to the null hypothesis. This may be viewed as a false negative result. When considering the risk of Type 2 error, it is more intuitive to think in terms of power of the study or (1 − β). Power denotes the probability of detecting a difference when a difference does exist between the groups being compared. Smaller α or larger power will increase sample size. Conventional acceptable values for power and α are 80% or above and 5% or below, respectively, when calculating sample size. Increasing variance in the sample tends to increase the sample size required to achieve a given power level. The effect size is the smallest clinically important difference that is sought to be detected and, rather than statistical convention, is a matter of past experience and clinical judgment. Larger samples are required if smaller differences are to be detected. Although the principles are long known, historically, sample size determination has been difficult, because of relatively complex mathematical considerations and numerous different formulas. However, of late, there has been remarkable improvement in the availability, capability, and user-friendliness of power and sample size determination software. Many can execute routines for determination of sample size and power for a wide variety of research designs and statistical tests. With the drudgery of mathematical calculation gone, researchers must now concentrate on determining appropriate sample size and achieving these targets, so that study conclusions can be accepted as meaningful. PMID:27688437

Sample size and power for cost-effectiveness analysis (part 1).

PubMed

Glick, Henry A

2011-03-01

Basic sample size and power formulae for cost-effectiveness analysis have been established in the literature. These formulae are reviewed and the similarities and differences between sample size and power for cost-effectiveness analysis and for the analysis of other continuous variables such as changes in blood pressure or weight are described. The types of sample size and power tables that are commonly calculated for cost-effectiveness analysis are also described and the impact of varying the assumed parameter values on the resulting sample size and power estimates is discussed. Finally, the way in which the data for these calculations may be derived are discussed.

Estimation of sample size and testing power (Part 4).

PubMed

Hu, Liang-ping; Bao, Xiao-lei; Guan, Xue; Zhou, Shi-guo

2012-01-01

Sample size estimation is necessary for any experimental or survey research. An appropriate estimation of sample size based on known information and statistical knowledge is of great significance. This article introduces methods of sample size estimation of difference test for data with the design of one factor with two levels, including sample size estimation formulas and realization based on the formulas and the POWER procedure of SAS software for quantitative data and qualitative data with the design of one factor with two levels. In addition, this article presents examples for analysis, which will play a leading role for researchers to implement the repetition principle during the research design phase.

[Formal sample size calculation and its limited validity in animal studies of medical basic research].

PubMed

Mayer, B; Muche, R

2013-01-01

Animal studies are highly relevant for basic medical research, although their usage is discussed controversially in public. Thus, an optimal sample size for these projects should be aimed at from a biometrical point of view. Statistical sample size calculation is usually the appropriate methodology in planning medical research projects. However, required information is often not valid or only available during the course of an animal experiment. This article critically discusses the validity of formal sample size calculation for animal studies. Within the discussion, some requirements are formulated to fundamentally regulate the process of sample size determination for animal experiments.

Efficacy of gradual pressure-decline compressing stockings in Asian patients with lower leg varicose veins: analysis by general measurements and magnetic resonance image.

PubMed

Leung, T K; Lin, J M; Chu, C L; Wu, Y S; Chao, Y J

2012-12-01

Most applications of gradual pressure-decline compressing stockings (GPDCS) are used in the United States and Western European countries, with over a decade of clinical experiments. Up to know, there is no standard establishment of gradual pressure-decline compressing stockings for Asian patients with venous insufficiency and varicose vein formations. We collected data on volunteer candidates of varicose vein for general measurements and assessments and magnetic resonance imaging (MRI) by non-contrast enhanced MRV techniques, and for post processing data analysis. Clinical use of GPCDS provide a mild to moderate improvement in the varicose vein conditions of patients with deep venous insufficiency by improving their deep vein circulation, by general measurements; recording major symptoms and complaint; comfort and stretching/flexibility to the candidates after using GPDCS; and area changes/flow velocity changes/available hemoglobin changes in deep veins monitored by MRI. The benefits and data collected in these results may help in developing compression stockings standards in Taiwanese and Asian countries, and to establishing criterias for product sizes, compression levels, and related parameters.

New lethal disease involving type I and III collagen defect resembling geroderma osteodysplastica, De Barsy syndrome, and Ehlers-Danlos syndrome IV.

PubMed

Jukkola, A; Kauppila, S; Risteli, L; Vuopala, K; Risteli, J; Leisti, J; Pajunen, L

1998-06-01

We describe the clinical findings and biochemical features of a male child suffering from a so far undescribed lethal connective tissue disorder characterised by extreme hypermobility of the joints, lax skin, cataracts, severe growth retardation, and insufficient production of type I and type III procollagens. His features are compared with Ehlers-Danlos type IV, De Barsy syndrome, and geroderma osteodysplastica, as these disorders show some symptoms and signs shared with our patient. The child died because of failure of the connective tissue structures joining the skull and the spine, leading to progressive spinal stenosis. The aortic valve was translucent and insufficient. The clinical symptoms and signs, together with histological findings, suggested a collagen defect. Studies on both skin fibroblast cultures and the patient's serum showed reduced synthesis of collagen types I and III at the protein and RNA levels. The sizes of the mRNAs and newly synthesised proteins were normal, excluding gross structural abnormalities. These findings are not in accordance with any other collagen defect characterised so far.

A sequential bioequivalence design with a potential ethical advantage.

PubMed

Fuglsang, Anders

2014-07-01

This paper introduces a two-stage approach for evaluation of bioequivalence, where, in contrast to the designs of Diane Potvin and co-workers, two stages are mandatory regardless of the data obtained at stage 1. The approach is derived from Potvin's method C. It is shown that under circumstances with relatively high variability and relatively low initial sample size, this method has an advantage over Potvin's approaches in terms of sample sizes while controlling type I error rates at or below 5% with a minute occasional trade-off in power. Ethically and economically, the method may thus be an attractive alternative to the Potvin designs. It is also shown that when using the method introduced here, average total sample sizes are rather independent of initial sample size. Finally, it is shown that when a futility rule in terms of sample size for stage 2 is incorporated into this method, i.e., when a second stage can be abolished due to sample size considerations, there is often an advantage in terms of power or sample size as compared to the previously published methods.

Sample Size Determination for One- and Two-Sample Trimmed Mean Tests

ERIC Educational Resources Information Center

Luh, Wei-Ming; Olejnik, Stephen; Guo, Jiin-Huarng

2008-01-01

Formulas to determine the necessary sample sizes for parametric tests of group comparisons are available from several sources and appropriate when population distributions are normal. However, in the context of nonnormal population distributions, researchers recommend Yuen's trimmed mean test, but formulas to determine sample sizes have not been…

The cost of large numbers of hypothesis tests on power, effect size and sample size.

PubMed

Lazzeroni, L C; Ray, A

2012-01-01

Advances in high-throughput biology and computer science are driving an exponential increase in the number of hypothesis tests in genomics and other scientific disciplines. Studies using current genotyping platforms frequently include a million or more tests. In addition to the monetary cost, this increase imposes a statistical cost owing to the multiple testing corrections needed to avoid large numbers of false-positive results. To safeguard against the resulting loss of power, some have suggested sample sizes on the order of tens of thousands that can be impractical for many diseases or may lower the quality of phenotypic measurements. This study examines the relationship between the number of tests on the one hand and power, detectable effect size or required sample size on the other. We show that once the number of tests is large, power can be maintained at a constant level, with comparatively small increases in the effect size or sample size. For example at the 0.05 significance level, a 13% increase in sample size is needed to maintain 80% power for ten million tests compared with one million tests, whereas a 70% increase in sample size is needed for 10 tests compared with a single test. Relative costs are less when measured by increases in the detectable effect size. We provide an interactive Excel calculator to compute power, effect size or sample size when comparing study designs or genome platforms involving different numbers of hypothesis tests. The results are reassuring in an era of extreme multiple testing.

Thirty-day outcomes underestimate endocrine and exocrine insufficiency after pancreatic resection.

PubMed

Lim, Pei-Wen; Dinh, Kate H; Sullivan, Mary; Wassef, Wahid Y; Zivny, Jaroslav; Whalen, Giles F; LaFemina, Jennifer

2016-04-01

Long-term incidence of endocrine and exocrine insufficiency after pancreatectomy is poorly described. We analyze the long-term risks of pancreatic insufficiency after pancreatectomy. Subjects who underwent pancreatectomy from 2002 to 2012 were identified from a prospective database (n = 227). Subjects who underwent total pancreatectomy or pancreatitis surgery were excluded. New post-operative endocrine and exocrine insufficiency was defined as the need for new pharmacologic intervention within 1000 days from resection. 28 (16%) of 178 subjects without pre-existing endocrine insufficiency developed post-operative endocrine insufficiency: 7 (25%) did so within 30 days, 8 (29%) between 30 and 90 days, and 13 (46%) after 90 days. 94 (43%) of 214 subjects without pre-operative exocrine insufficiency developed exocrine insufficiency: 20 (21%) did so within 30 days, 29 (31%) between 30 and 90 days, and 45 (48%) after 90 days. Adjuvant radiation was associated with new endocrine insufficiency. On multivariate regression, pancreaticoduodenectomy and chemotherapy were associated with a greater risk of exocrine insufficiency. Reporting 30-day functional outcomes for pancreatic resection is insufficient, as nearly 45% of subjects who develop disease do so after 90 days. Reporting of at least 90-day outcomes may more reliably assess risk for post-operative endocrine and exocrine insufficiency. Copyright © 2016 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.

The Statistics and Mathematics of High Dimension Low Sample Size Asymptotics.

PubMed

Shen, Dan; Shen, Haipeng; Zhu, Hongtu; Marron, J S

2016-10-01

The aim of this paper is to establish several deep theoretical properties of principal component analysis for multiple-component spike covariance models. Our new results reveal an asymptotic conical structure in critical sample eigendirections under the spike models with distinguishable (or indistinguishable) eigenvalues, when the sample size and/or the number of variables (or dimension) tend to infinity. The consistency of the sample eigenvectors relative to their population counterparts is determined by the ratio between the dimension and the product of the sample size with the spike size. When this ratio converges to a nonzero constant, the sample eigenvector converges to a cone, with a certain angle to its corresponding population eigenvector. In the High Dimension, Low Sample Size case, the angle between the sample eigenvector and its population counterpart converges to a limiting distribution. Several generalizations of the multi-spike covariance models are also explored, and additional theoretical results are presented.

Influence of item distribution pattern and abundance on efficiency of benthic core sampling

USGS Publications Warehouse

Behney, Adam C.; O'Shaughnessy, Ryan; Eichholz, Michael W.; Stafford, Joshua D.

2014-01-01

ore sampling is a commonly used method to estimate benthic item density, but little information exists about factors influencing the accuracy and time-efficiency of this method. We simulated core sampling in a Geographic Information System framework by generating points (benthic items) and polygons (core samplers) to assess how sample size (number of core samples), core sampler size (cm2), distribution of benthic items, and item density affected the bias and precision of estimates of density, the detection probability of items, and the time-costs. When items were distributed randomly versus clumped, bias decreased and precision increased with increasing sample size and increased slightly with increasing core sampler size. Bias and precision were only affected by benthic item density at very low values (500–1,000 items/m2). Detection probability (the probability of capturing ≥ 1 item in a core sample if it is available for sampling) was substantially greater when items were distributed randomly as opposed to clumped. Taking more small diameter core samples was always more time-efficient than taking fewer large diameter samples. We are unable to present a single, optimal sample size, but provide information for researchers and managers to derive optimal sample sizes dependent on their research goals and environmental conditions.

Moment and maximum likelihood estimators for Weibull distributions under length- and area-biased sampling

Treesearch

Jeffrey H. Gove

2003-01-01

Many of the most popular sampling schemes used in forestry are probability proportional to size methods. These methods are also referred to as size biased because sampling is actually from a weighted form of the underlying population distribution. Length- and area-biased sampling are special cases of size-biased sampling where the probability weighting comes from a...

Optimal spatial sampling techniques for ground truth data in microwave remote sensing of soil moisture

NASA Technical Reports Server (NTRS)

Rao, R. G. S.; Ulaby, F. T.

1977-01-01

The paper examines optimal sampling techniques for obtaining accurate spatial averages of soil moisture, at various depths and for cell sizes in the range 2.5-40 acres, with a minimum number of samples. Both simple random sampling and stratified sampling procedures are used to reach a set of recommended sample sizes for each depth and for each cell size. Major conclusions from statistical sampling test results are that (1) the number of samples required decreases with increasing depth; (2) when the total number of samples cannot be prespecified or the moisture in only one single layer is of interest, then a simple random sample procedure should be used which is based on the observed mean and SD for data from a single field; (3) when the total number of samples can be prespecified and the objective is to measure the soil moisture profile with depth, then stratified random sampling based on optimal allocation should be used; and (4) decreasing the sensor resolution cell size leads to fairly large decreases in samples sizes with stratified sampling procedures, whereas only a moderate decrease is obtained in simple random sampling procedures.

Effects of sample size on estimates of population growth rates calculated with matrix models.

PubMed

Fiske, Ian J; Bruna, Emilio M; Bolker, Benjamin M

2008-08-28

Matrix models are widely used to study the dynamics and demography of populations. An important but overlooked issue is how the number of individuals sampled influences estimates of the population growth rate (lambda) calculated with matrix models. Even unbiased estimates of vital rates do not ensure unbiased estimates of lambda-Jensen's Inequality implies that even when the estimates of the vital rates are accurate, small sample sizes lead to biased estimates of lambda due to increased sampling variance. We investigated if sampling variability and the distribution of sampling effort among size classes lead to biases in estimates of lambda. Using data from a long-term field study of plant demography, we simulated the effects of sampling variance by drawing vital rates and calculating lambda for increasingly larger populations drawn from a total population of 3842 plants. We then compared these estimates of lambda with those based on the entire population and calculated the resulting bias. Finally, we conducted a review of the literature to determine the sample sizes typically used when parameterizing matrix models used to study plant demography. We found significant bias at small sample sizes when survival was low (survival = 0.5), and that sampling with a more-realistic inverse J-shaped population structure exacerbated this bias. However our simulations also demonstrate that these biases rapidly become negligible with increasing sample sizes or as survival increases. For many of the sample sizes used in demographic studies, matrix models are probably robust to the biases resulting from sampling variance of vital rates. However, this conclusion may depend on the structure of populations or the distribution of sampling effort in ways that are unexplored. We suggest more intensive sampling of populations when individual survival is low and greater sampling of stages with high elasticities.

Detection of West Nile virus and tick-borne encephalitis virus in birds in Slovakia, using a universal primer set.

PubMed

Csank, Tomáš; Bhide, Katarína; Bencúrová, Elena; Dolinská, Saskia; Drzewnioková, Petra; Major, Peter; Korytár, Ľuboš; Bocková, Eva; Bhide, Mangesh; Pistl, Juraj

2016-06-01

West Nile virus (WNV) is a mosquito-borne neurotropic pathogen that presents a major public health concern. Information on WNV prevalence and circulation in Slovakia is insufficient. Oral and cloacal swabs and bird brain samples were tested for flavivirus RNA by RT-PCR using newly designed generic primers. The species designation was confirmed by sequencing. WNV was detected in swab and brain samples, whereas one brain sample was positive for tick-borne encephalitis virus (TBEV). The WNV sequences clustered with lineages 1 and 2. These results confirm the circulation of WNV in birds in Slovakia and emphasize the risk of infection of humans and horses.

Generation and emplacement of fine-grained ejecta in planetary impacts

USGS Publications Warehouse

Ghent, R.R.; Gupta, V.; Campbell, B.A.; Ferguson, S.A.; Brown, J.C.W.; Fergason, R.L.; Carter, L.M.

2010-01-01

We report here on a survey of distal fine-grained ejecta deposits on the Moon, Mars, and Venus. On all three planets, fine-grained ejecta form circular haloes that extend beyond the continuous ejecta and other types of distal deposits such as run-out lobes or ramparts. Using Earth-based radar images, we find that lunar fine-grained ejecta haloes represent meters-thick deposits with abrupt margins, and are depleted in rocks 1cm in diameter. Martian haloes show low nighttime thermal IR temperatures and thermal inertia, indicating the presence of fine particles estimated to range from ???10??m to 10mm. Using the large sample sizes afforded by global datasets for Venus and Mars, and a complete nearside radar map for the Moon, we establish statistically robust scaling relationships between crater radius R and fine-grained ejecta run-out r for all three planets. On the Moon, ???R-0.18 for craters 5-640km in diameter. For Venus, radar-dark haloes are larger than those on the Moon, but scale as ???R-0.49, consistent with ejecta entrainment in Venus' dense atmosphere. On Mars, fine-ejecta haloes are larger than lunar haloes for a given crater size, indicating entrainment of ejecta by the atmosphere or vaporized subsurface volatiles, but scale as R-0.13, similar to the ballistic lunar scaling. Ejecta suspension in vortices generated by passage of the ejecta curtain is predicted to result in ejecta run-out that scales with crater size as R1/2, and the wind speeds so generated may be insufficient to transport particles at the larger end of the calculated range. The observed scaling and morphology of the low-temperature haloes leads us rather to favor winds generated by early-stage vapor plume expansion as the emplacement mechanism for low-temperature halo materials. ?? 2010 Elsevier Inc.

Applicability of optical scanner method for fine root dynamics

NASA Astrophysics Data System (ADS)

Kume, Tomonori; Ohashi, Mizue; Makita, Naoki; Khoon Kho, Lip; Katayama, Ayumi; Matsumoto, Kazuho; Ikeno, Hidetoshi

2016-04-01

Fine root dynamics is one of the important components in forest carbon cycling, as ~60 % of tree photosynthetic production can be allocated to root growth and metabolic activities. Various techniques have been developed for monitoring fine root biomass, production, mortality in order to understand carbon pools and fluxes resulting from fine roots dynamics. The minirhizotron method is now a widely used technique, in which a transparent tube is inserted into the soil and researchers count an increase and decrease of roots along the tube using images taken by a minirhizotron camera or minirhizotron video camera inside the tube. This method allows us to observe root behavior directly without destruction, but has several weaknesses; e.g., the difficulty of scaling up the results to stand level because of the small observation windows. Also, most of the image analysis are performed manually, which may yield insufficient quantitative and objective data. Recently, scanner method has been proposed, which can produce much bigger-size images (A4-size) with lower cost than those of the minirhizotron methods. However, laborious and time-consuming image analysis still limits the applicability of this method. In this study, therefore, we aimed to develop a new protocol for scanner image analysis to extract root behavior in soil. We evaluated applicability of this method in two ways; 1) the impact of different observers including root-study professionals, semi- and non-professionals on the detected results of root dynamics such as abundance, growth, and decomposition, and 2) the impact of window size on the results using a random sampling basis exercise. We applied our new protocol to analyze temporal changes of root behavior from sequential scanner images derived from a Bornean tropical forests. The results detected by the six observers showed considerable concordance in temporal changes in the abundance and the growth of fine roots but less in the decomposition. We also examined potential errors due to window size in the temporal changes in abundance and growth using the detected results, suggesting high applicability of the scanner methods with wide observation windows.

Lateral thrust of anterior cruciate ligament-insufficient knees and posterior cruciate ligament-insufficient knees.

PubMed

Yoshimura, Ichiro; Naito, Masatoshi; Zhang, Jingfan

2002-01-01

Leaving anterior cruciate ligament (ACL) insufficiency and posterior cruciate ligament (PCL) insufficiency untreated frequently leads to osteoarthritis (OA). The purpose of this study was to evaluate dynamically the lateral thrust of ACL-insufficient knees and PCL-insufficient knees, and from the findings investigate the relationship between cruciate ligament insufficiency and OA occurrence. An acceleration sensor was attached to the affected and control anterior tibial tubercles, acting in medial-lateral and perpendicular directions. The lateral thrust immediately after heel strike was measured continuously by a telemeter under stabilised walking conditions. When compared to the contralateral healthy knee, the peak value of lateral acceleration immediately after heel strike was significantly larger in the ACL-insufficient knee; and lateral thrust was increased, but not significantly, in the PCL-insufficient knee. Given that lateral thrust of the knee during walking increases due to ACL or PCL injury, it may be a principal contributor to OA progression.

76 FR 56141 - Notice of Intent To Request New Information Collection

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-12

... level surveys of similar scope and size. The sample for each selected community will be strategically... of 2 hours per sample community. Full Study: The maximum sample size for the full study is 2,812... questionnaires. The initial sample size for this phase of the research is 100 respondents (10 respondents per...

Determining Sample Size for Accurate Estimation of the Squared Multiple Correlation Coefficient.

ERIC Educational Resources Information Center

Algina, James; Olejnik, Stephen

2000-01-01

Discusses determining sample size for estimation of the squared multiple correlation coefficient and presents regression equations that permit determination of the sample size for estimating this parameter for up to 20 predictor variables. (SLD)

[Practical aspects regarding sample size in clinical research].

PubMed

Vega Ramos, B; Peraza Yanes, O; Herrera Correa, G; Saldívar Toraya, S

1996-01-01

The knowledge of the right sample size let us to be sure if the published results in medical papers had a suitable design and a proper conclusion according to the statistics analysis. To estimate the sample size we must consider the type I error, type II error, variance, the size of the effect, significance and power of the test. To decide what kind of mathematics formula will be used, we must define what kind of study we have, it means if its a prevalence study, a means values one or a comparative one. In this paper we explain some basic topics of statistics and we describe four simple samples of estimation of sample size.

Breaking Free of Sample Size Dogma to Perform Innovative Translational Research

PubMed Central

Bacchetti, Peter; Deeks, Steven G.; McCune, Joseph M.

2011-01-01

Innovative clinical and translational research is often delayed or prevented by reviewers’ expectations that any study performed in humans must be shown in advance to have high statistical power. This supposed requirement is not justifiable and is contradicted by the reality that increasing sample size produces diminishing marginal returns. Studies of new ideas often must start small (sometimes even with an N of 1) because of cost and feasibility concerns, and recent statistical work shows that small sample sizes for such research can produce more projected scientific value per dollar spent than larger sample sizes. Renouncing false dogma about sample size would remove a serious barrier to innovation and translation. PMID:21677197

What is the optimum sample size for the study of peatland testate amoeba assemblages?

PubMed

Mazei, Yuri A; Tsyganov, Andrey N; Esaulov, Anton S; Tychkov, Alexander Yu; Payne, Richard J

2017-10-01

Testate amoebae are widely used in ecological and palaeoecological studies of peatlands, particularly as indicators of surface wetness. To ensure data are robust and comparable it is important to consider methodological factors which may affect results. One significant question which has not been directly addressed in previous studies is how sample size (expressed here as number of Sphagnum stems) affects data quality. In three contrasting locations in a Russian peatland we extracted samples of differing size, analysed testate amoebae and calculated a number of widely-used indices: species richness, Simpson diversity, compositional dissimilarity from the largest sample and transfer function predictions of water table depth. We found that there was a trend for larger samples to contain more species across the range of commonly-used sample sizes in ecological studies. Smaller samples sometimes failed to produce counts of testate amoebae often considered minimally adequate. It seems likely that analyses based on samples of different sizes may not produce consistent data. Decisions about sample size need to reflect trade-offs between logistics, data quality, spatial resolution and the disturbance involved in sample extraction. For most common ecological applications we suggest that samples of more than eight Sphagnum stems are likely to be desirable. Copyright © 2017 Elsevier GmbH. All rights reserved.

Measurement of lumefantrine and its metabolite in plasma by high performance liquid chromatography with ultraviolet detection.

PubMed

Khalil, Insaf F; Abildrup, Ulla; Alifrangis, Lene H; Maiga, Deogratius; Alifrangis, Michael; Hoegberg, Lotte; Vestergaard, Lasse S; Persson, Ola Per-Eric; Nyagonde, Nyagonde; Lemnge, Martha M; Theander, Thor G; Bygbjerg, Ib C

2011-01-05

Artemether-lumefantrine (ARM-LUM) has in recent years become the first-line treatment for uncomplicated malaria in many Sub-Saharan African countries. Vigorous monitoring of the therapeutic efficacy of this treatment is needed. This requires high-quality studies following standard protocols; ideally, such studies should incorporate measurement of drug levels in the study patients to exclude the possibility that insufficient drug levels explain an observed treatment failure. Several methods for measuring lumefantrine (LUM) in plasma by HPLC are available; however, several of these methods have some limitations in terms of high costs and limited feasibility arising from large required sample volumes and demanding sample preparation. Therefore, we set out to develop a simpler reversed phase high performance liquid chromatography (RP-HPLC) method based on UV detection for simultaneous measurement of LUM and its major metabolite the desbutyl LUM (DL) in plasma. Halofantrine was used as an internal standard. Liquid-liquid extraction of samples was carried out using hexane-ethyl acetate (70:30, v/v). Chromatographic separation was carried out on a Synergi Polar-RP column (250 mm × 300 mm, particle size 4 μm). The mobile phase consisted of acetonitrile-0.1M ammonium acetate buffer adjusted to pH 4.9 (85:15%, v/v). Absorbance of the compounds was monitored at 335 nm using a reference wavelength of 360 nm. Absolute extraction recovery for LUM and DL were 88% and 90%, respectively. Inter- and intraday coefficients of variation for LUM and DL were ≤ 10%. The lower limits of quantification for LUM and DL were 12.5 and 6.5 ng/ml, respectively. After validation, the methodology was transferred to a local laboratory in Tanga Tanzania and samples from a small subset of malaria patients were analysed for LUM. The method appears to be applicable in settings with limited facilities. Copyright © 2010 Elsevier B.V. All rights reserved.

Physical activity in the older adults related to commuting and leisure, Maceió, Brazil

PubMed Central

Mourão, Ana Raquel de Carvalho; Novais, Francini Vilela; Andreoni, Solange; Ramos, Luiz Roberto

2013-01-01

OBJECTIVE To evaluate the level of physical activity of older adults by commuting and leisure time and associated factors. METHODS This was a cross-sectional study carried out with a population-based sample of 319 older individuals in Maceió, AL, Northeastern Brazil, in 2009. The level of physical activity in leisure and commuting was measured by applying the International Physical Activity Questionnaire, long version. The variables analyzed were: age, schooling, sex, per capita income and perceived health. We used descriptive analysis, Fisher's exact test and multiple regression analysis of prevalence rates. RESULTS We classified 87.5% as insufficiently active in commuting, being significantly higher among those individuals with older ages, with more education and who feel dissatisfied with their physical health. The prevalence of older people who are insufficiently active in leisure time activity was 76.2%, being more frequent in women, in men with advanced age; older adults with lower per capita income, and dissatisfaction with comparative physical health and self-perceived mental health. CONCLUSIONS The prevalence of insufficiently active was high in commuting and leisure time activities. Factors such as age, gender and income should be considered, especially with regards leisure, in order to ensure fairness in the development of policies to promote health and physical activity in this population. PMID:24626549

[Physical activity in the older adults related to commuting and leisure, Maceió, Brazil].

PubMed

Mourão, Ana Raquel de Carvalho; Novais, Francini Vilela; Andreoni, Solange; Ramos, Luiz Roberto

2013-12-01

To evaluate the level of physical activity of older adults by commuting and leisure time and associated factors. This was a cross-sectional study carried out with a population-based sample of 319 older individuals in Maceió, AL, Northeastern Brazil, in 2009. The level of physical activity in leisure and commuting was measured by applying the International Physical Activity Questionnaire, long version. The variables analyzed were: age, schooling, sex, per capita income and perceived health. We used descriptive analysis, Fisher's exact test and multiple regression analysis of prevalence rates. We classified 87.5% as insufficiently active in commuting, being significantly higher among those individuals with older ages, with more education and who feel dissatisfied with their physical health. The prevalence of older people who are insufficiently active in leisure time activity was 76.2%, being more frequent in women, in men with advanced age; older adults with lower per capita income, and dissatisfaction with comparative physical health and self-perceived mental health. The prevalence of insufficiently active was high in commuting and leisure time activities. Factors such as age, gender and income should be considered, especially with regards leisure, in order to ensure fairness in the development of policies to promote health and physical activity in this population.

Prenatal folate, homocysteine and vitamin B12 levels and child brain volumes, cognitive development and psychological functioning: the Generation R Study.

PubMed

Ars, Charlotte L; Nijs, Ilse M; Marroun, Hanan E; Muetzel, Ryan; Schmidt, Marcus; Steenweg-de Graaff, Jolien; van der Lugt, Aad; Jaddoe, Vincent W; Hofman, Albert; Steegers, Eric A; Verhulst, Frank C; Tiemeier, Henning; White, Tonya

2016-01-22

Previous studies have suggested that prenatal maternal folate deficiency is associated with reduced prenatal brain growth and psychological problems in offspring. However, little is known about the longer-term impact. The aims of this study were to investigate whether prenatal maternal folate insufficiency, high total homocysteine levels and low vitamin B12 levels are associated with altered brain morphology, cognitive and/or psychological problems in school-aged children. This study was embedded in Generation R, a prospective population-based cohort study. The study sample consisted of 256 Dutch children aged between 6 and 8 years from whom structural brain scans were collected using MRI. The mothers of sixty-two children had insufficient (9·1 µmol/l) predicted poorer performance on the language (B -0·31; 95 % CI -0·56, -0·06; P=0·014) and visuo-spatial domains (B -0·36; 95 % CI -0·60, -0·11; P=0·004). No associations with psychological problems were found. Our findings suggest that folate insufficiency in early pregnancy has a long-lasting, global effect on brain development and is, together with homocysteine levels, associated with poorer cognitive performance.

Insufficient sleep and suicidality in adolescents.

PubMed

Lee, Yu Jin; Cho, Seong-Jin; Cho, In Hee; Kim, Seog Ju

2012-04-01

To investigate the association between the behaviorally induced insufficient sleep and suicidality among adolescents. A population-based, cross-sectional survey. General community. A sample of 8,530 students (grades 7-11) was recruited in the Republic of Korea. The participants were 8,010 students who completed all questionnaires. N/A. The survey included the Beck Scale for Suicidal Ideation (SSI), the Beck Depression Inventory (BDI), a modified Epworth Sleepiness Scale (ESS), and questionnaires about sleep (weekday/weekend sleep schedule/duration, insomnia and snoring). Adolescents with behaviorally induced insufficient sleep syndrome (BISS) had higher SSI scores than those who slept ≥ 7 hours on weekdays, even after controlling for age, sex, and BDI score (F = 11.71, P < 0.001). After controlling for age and sex, longer weekend oversleep and shorter weekday sleep duration predicted a higher SSI score (β = 0.19, P < 0.001; β = 0.37, P < 0.001). The association between weekend oversleep and SSI score remained significant even after additionally controlling for BDI and ESS scores and presence of insomnia and snoring (β = 0.07, P < 0.01). BISS was found to be associated with increased suicidality. Weekend oversleep was associated with suicidality independently of depression, daytime sleepiness, snoring, and insomnia. The study findings suggest that chronic sleep restriction among adolescents may increase suicidal risk.

Sample Size and Allocation of Effort in Point Count Sampling of Birds in Bottomland Hardwood Forests

Treesearch

Winston P. Smith; Daniel J. Twedt; Robert J. Cooper; David A. Wiedenfeld; Paul B. Hamel; Robert P. Ford

1995-01-01

To examine sample size requirements and optimum allocation of effort in point count sampling of bottomland hardwood forests, we computed minimum sample sizes from variation recorded during 82 point counts (May 7-May 16, 1992) from three localities containing three habitat types across three regions of the Mississippi Alluvial Valley (MAV). Also, we estimated the effect...