Inking and Thinking: Honors Students and Tattoos

ERIC Educational Resources Information Center

Dundes, Lauren; Francis, Antonia

2016-01-01

This study examines whether academically accelerated students in a college Honors program are as likely as other students to acquire a tattoo and to spend the same amount of time contemplating this decision. A convenience sample of 71 honors students and 135 non-honors students completed a survey at a small mid-Atlantic liberal arts college in…

Sampling considerations for disease surveillance in wildlife populations

USGS Publications Warehouse

Nusser, S.M.; Clark, W.R.; Otis, D.L.; Huang, L.

2008-01-01

Disease surveillance in wildlife populations involves detecting the presence of a disease, characterizing its prevalence and spread, and subsequent monitoring. A probability sample of animals selected from the population and corresponding estimators of disease prevalence and detection provide estimates with quantifiable statistical properties, but this approach is rarely used. Although wildlife scientists often assume probability sampling and random disease distributions to calculate sample sizes, convenience samples (i.e., samples of readily available animals) are typically used, and disease distributions are rarely random. We demonstrate how landscape-based simulation can be used to explore properties of estimators from convenience samples in relation to probability samples. We used simulation methods to model what is known about the habitat preferences of the wildlife population, the disease distribution, and the potential biases of the convenience-sample approach. Using chronic wasting disease in free-ranging deer (Odocoileus virginianus) as a simple illustration, we show that using probability sample designs with appropriate estimators provides unbiased surveillance parameter estimates but that the selection bias and coverage errors associated with convenience samples can lead to biased and misleading results. We also suggest practical alternatives to convenience samples that mix probability and convenience sampling. For example, a sample of land areas can be selected using a probability design that oversamples areas with larger animal populations, followed by harvesting of individual animals within sampled areas using a convenience sampling method.

Subtle imitation behaviour in convenience samples of normal, demented, and currently depressed elderly subjects.

PubMed

von Gunten, Armin; Duc, René

2007-06-01

The clinical significance of imitation behaviour (IB) is unclear. The aim of this study was to investigate the prevalence of subtle naïve and obstinate IB in convenience samples of normal elderly, demented, and depressed subjects. Subtle IB was assessed using a protocol constructed ad hoc in 146 patients, consecutively referred to a memory clinic having received an ICD-10 diagnosis of either dementia or depression, and in 241 healthy subjects. The prevalence of IB in the three groups was determined and the association with possible demographic, cognitive, and non-cognitive variables analysed. Subtle naïve IB was frequent in the elderly with dementia, intermediate in the depressed, and rare in the normal elderly except that the latter frequently stretched out their arms. Obstinate IB never occurred in the normal elderly. IB was predicted by none of the variables used. The groups included were convenience samples with the depressed being a small group precluding further distinction of depressive subtypes. Although naïve IB is a frequent clinical feature in the demented, it also accompanies depressive disorders in the elderly. It can be observed as context-specific IB in the normal elderly. Obstinate IB does not occur in the normal elderly. Copyright 2006 John Wiley & Sons, Ltd.

Sample mounts for microcrystal crystallography

NASA Technical Reports Server (NTRS)

Thorne, Robert E. (Inventor); Kmetko, Jan (Inventor); Stum, Zachary (Inventor); O'Neill, Kevin (Inventor)

2007-01-01

Sample mounts (10) for mounting microcrystals of biological macromolecules for X-ray crystallography are prepared by using patterned thin polyimide films (12) that have curvature imparted thereto, for example, by being attached to a curved outer surface of a small metal rod (16). The patterned film (12) preferably includes a tapered tip end (24) for holding a crystal. Preferably, a small sample aperture is disposed in the film for reception of the crystal. A second, larger aperture can also be provided that is connected to the sample aperture by a drainage channel, allowing removal of excess liquid and easier manipulation in viscous solutions. The curvature imparted to the film (12) increases the film's rigidity and allows a convenient scoop-like action for retrieving crystals. The polyimide contributes minimally to background and absorption, and can be treated to obtain desired hydrophobicity or hydrophilicity.

Sample mounts for microcrystal crystallography

NASA Technical Reports Server (NTRS)

O'Neill, Kevin (Inventor); Kmetko, Jan (Inventor); Thorne, Robert E. (Inventor); Stum, Zachary (Inventor)

2009-01-01

Sample mounts (10) for mounting microcrystals of biological macromolecules for X-ray crystallography are prepared by using patterned thin polyimide films (12) that have curvature imparted thereto, for example, by being attached to a curved outer surface of a small metal rod (16). The patterned film (12) preferably includes a tip end (24) for holding a crystal. Preferably, a small sample aperture is disposed in the film for reception of the crystal. A second, larger aperture can also be provided that is connected to the sample aperture by a drainage channel, allowing removal of excess liquid and easier manipulation in viscous solutions. The curvature imparted to the film (12) increases the film's rigidity and allows a convenient scoop-like action for retrieving crystals. The polyimide contributes minimally to background and absorption, and can be treated to obtain desired hydrophobicity or hydrophilicity.

A microplate assay for DNA damage determination (fast micromethod).

PubMed

Batel, R; Jaksić, Z; Bihari, N; Hamer, B; Fafandel, M; Chauvin, C; Schröder, H C; Müller, W E; Zahn, R K

1999-06-01

A rapid and convenient procedure for DNA damage determination in cell suspensions and solid tissues on single microplates was developed. The procedure is based on the ability of commercially available fluorochromes to interact preferentially with dsDNA in the presence of ssDNA, RNA, and proteins at high pH (>12.0), thus allowing direct measurements of DNA denaturation without sample handling or stepwise DNA separations. The method includes a simple and rapid 40-min sample lysis in the presence of EDTA, SDS, and high urea concentration at pH 10, followed by time-dependent DNA denaturation at pH 12.4 after NaOH addition. The time course and the extent of DNA denaturation is followed in a microplate fluorescence reader at room temperature for less than 1 h. The method requires only 30 ng DNA per single well and could conveniently be used whenever fast analysis of DNA integrity in small samples has to be done, e.g., in patients' lymphocytes after irradiation or chemotherapy (about 3000 cells per sample), in solid tissues or biopsies after homogenization (about 25 microg tissue per well), or in environmental samples for genotoxicity assessment. Copyright 1999 Academic Press.

Sampling in research on interpersonal aggression.

PubMed

Nielsen, Morten Birkeland; Einarsen, Ståle

2008-01-01

The aim of this study was to investigate the usefulness of convenience samples in research on interpersonal aggression among adults. It was hypothesised that convenience sampled targets of aggression differs from targets in general with regards to both demographic characteristics and degree of aggression exposed to. A convenience sample comprising support-seeking targets of workplace bullying was compared with a representative sample of Norwegian targets of bullying. The results showed that the two samples differed significantly on all demographic variables investigated, except gender. A far higher percentage of the convenience sample had blown the whistle on illegal, immoral or illegitimate practice at their workplace, whereas they also reported significantly more frequent and more intense exposure to aggression. The findings confirm that convenience samples have low external validity when generalising to the general population. Such samples should therefore mainly be used to investigate tendencies in, and the phenomenology of, interpersonal aggression, in studies where generalisability is not the principal objective. Copyright 2007 Wiley-Liss, Inc.

Assessing representativeness of sampling methods for reaching men who have sex with men: a direct comparison of results obtained from convenience and probability samples.

PubMed

Schwarcz, Sandra; Spindler, Hilary; Scheer, Susan; Valleroy, Linda; Lansky, Amy

2007-07-01

Convenience samples are used to determine HIV-related behaviors among men who have sex with men (MSM) without measuring the extent to which the results are representative of the broader MSM population. We compared results from a cross-sectional survey of MSM recruited from gay bars between June and October 2001 to a random digit dial telephone survey conducted between June 2002 and January 2003. The men in the probability sample were older, better educated, and had higher incomes than men in the convenience sample, the convenience sample enrolled more employed men and men of color. Substance use around the time of sex was higher in the convenience sample but other sexual behaviors were similar. HIV testing was common among men in both samples. Periodic validation, through comparison of data collected by different sampling methods, may be useful when relying on survey data for program and policy development.

Public Attitudes toward Stuttering in Turkey: Probability versus Convenience Sampling

ERIC Educational Resources Information Center

Ozdemir, R. Sertan; St. Louis, Kenneth O.; Topbas, Seyhun

2011-01-01

Purpose: A Turkish translation of the "Public Opinion Survey of Human Attributes-Stuttering" ("POSHA-S") was used to compare probability versus convenience sampling to measure public attitudes toward stuttering. Method: A convenience sample of adults in Eskisehir, Turkey was compared with two replicates of a school-based,…

Convenience Samples and Caregiving Research: How Generalizable Are the Findings?

ERIC Educational Resources Information Center

Pruchno, Rachel A.; Brill, Jonathan E.; Shands, Yvonne; Gordon, Judith R.; Genderson, Maureen Wilson; Rose, Miriam; Cartwright, Francine

2008-01-01

Purpose: We contrast characteristics of respondents recruited using convenience strategies with those of respondents recruited by random digit dial (RDD) methods. We compare sample variances, means, and interrelationships among variables generated from the convenience and RDD samples. Design and Methods: Women aged 50 to 64 who work full time and…

A displacement pump procedure to load extracts for automated gel permeation chromatography.

PubMed

Daft, J; Hopper, M; Hensley, D; Sisk, R

1990-01-01

Automated gel permeation chromatography (GPC) effectively separates lipids from pesticides in sample extracts that contain fat. Using a large syringe to load sample extracts manually onto GPC models having 5 mL holding loops is awkward, slow, and potentially hazardous. Loading with a small-volume displacement pump, however, is convenient and fast (ca 1 loop every 20 s). And more importantly, the analyst is not exposed to toxic organic vapors because the loading pump and its connecting lines do not leak in the way that a syringe does.

Comparing sexual minority cancer survivors recruited through a cancer registry to convenience methods of recruitment.

PubMed

Boehmer, Ulrike; Clark, Melissa A; Timm, Alison; Glickman, Mark; Sullivan, Mairead

2011-01-01

Sexual minority women, defined as having a lesbian or bisexual identity or reporting a preference for a female partner, are not considered by cancer surveillance. This study assesses the representativeness of sexual minority breast cancer survivors, defined as having a lesbian or bisexual identity or reporting a preference for a female partner, who were recruited into a convenience sample compared with a population-based registry sample of sexual minority breast cancer survivors. Long-term survivors of non-metastatic breast cancer who self-reported as sexual minority were recruited from a cancer registry and subsequently from the community using convenience recruitment methods. Sexual minority breast cancer survivors who screened eligible participated in a telephone survey about their quality of life and factors associated therewith. Participants in the convenience sample were similar to the registry-based sample with respect to adjustment to cancer, physical health, trust in physician, coping, social support, and sexual minority experiences. Compared with the convenience sample, breast cancer survivors in the registry sample were more likely married, more educated, diagnosed more recently, at an earlier stage of cancer, and more likely treated with breast-conserving surgery; they differed on adjuvant therapies. Because sexual minority breast cancer survivors who volunteered for the community-based sample shared most characteristics of the sample recruited from the cancer registry, we concluded that the community sample had comparable representational quality. In the absence of cancer surveillance of sexual minorities, thoughtful convenience recruitment methods provide good representational quality convenience samples. Copyright © 2011 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

13 CFR 143.44 - Termination for convenience.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Termination for convenience. 143.44 Section 143.44 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION UNIFORM ADMINISTRATIVE... Reports, Records, Retention, and Enforcement § 143.44 Termination for convenience. Except as provided in...

Micro-quantity tissue digestion for metal measurements by use of a microwave acid-digestion bomb.

PubMed

Nicholson, J R; Savory, M G; Savory, J; Wills, M R

1989-03-01

We describe a simple and convenient method for processing small amounts of tissue samples for trace-metal measurements by atomic absorption spectrometry, by use of a modified Parr microwave digestion bomb. Digestion proceeds rapidly (less than or equal to 90 s) in a sealed Teflon-lined vessel that eliminates contamination or loss from volatilization. Small quantities of tissue (5-100 mg dry weight) are digested in high-purity nitric acid, yielding concentrations of analyte that can be measured directly without further sample manipulation. We analyzed National Institute of Standards and Technology bovine liver Standard Reference Material to verify the accuracy of the technique. We assessed the applicability of the technique to analysis for aluminum in bone by comparison with a dry ashing procedure.

Concentration by centrifugation for gas exchange EPR oximetry measurements with loop-gap resonators.

PubMed

Subczynski, Witold K; Felix, Christopher C; Klug, Candice S; Hyde, James S

2005-10-01

Measurement of the bimolecular collision rate between a spin label and oxygen is conveniently carried out using a gas permeable plastic sample tube of small diameter that fits a loop-gap resonator. It is often desirable to concentrate the sample by centrifugation in order to improve the signal-to-noise ratio (SNR), but the deformable nature of small plastic sample tubes presents technical problems. Solutions to these problems are described. Two geometries were considered: (i) a methylpentene polymer, TPX, from Mitsui Chemicals, at X-band and (ii) Teflon tubing with 0.075 mm wall thickness at Q-band. Sample holders were fabricated from Delrin that fit the Eppendorf microcentrifuge tubes and support the sample capillaries. For TPX, pressure of the sealant at the end of the sample tube against the Delrin sample holder provided an adequate seal. For Teflon, the holder permitted introduction of water around the tube in order to equalize pressures across the sealant during centrifugation. Typically, the SNR was improved by a factor of five to eight. Oxygen accessibility applications in site-directed spin labeling studies are discussed.

Concentration by centrifugation for gas exchange EPR oximetry measurements with loop-gap resonators

NASA Astrophysics Data System (ADS)

Subczynski, Witold K.; Felix, Christopher C.; Klug, Candice S.; Hyde, James S.

2005-10-01

Measurement of the bimolecular collision rate between a spin label and oxygen is conveniently carried out using a gas permeable plastic sample tube of small diameter that fits a loop-gap resonator. It is often desirable to concentrate the sample by centrifugation in order to improve the signal-to-noise ratio (SNR), but the deformable nature of small plastic sample tubes presents technical problems. Solutions to these problems are described. Two geometries were considered: (i) a methylpentene polymer, TPX, from Mitsui Chemicals, at X-band and (ii) Teflon tubing with 0.075 mm wall thickness at Q-band. Sample holders were fabricated from Delrin that fit the Eppendorf microcentrifuge tubes and support the sample capillaries. For TPX, pressure of the sealant at the end of the sample tube against the Delrin sample holder provided an adequate seal. For Teflon, the holder permitted introduction of water around the tube in order to equalize pressures across the sealant during centrifugation. Typically, the SNR was improved by a factor of five to eight. Oxygen accessibility applications in site-directed spin labeling studies are discussed.

Statistical considerations in evaluating pharmacogenomics-based clinical effect for confirmatory trials.

PubMed

Wang, Sue-Jane; O'Neill, Robert T; Hung, Hm James

2010-10-01

The current practice for seeking genomically favorable patients in randomized controlled clinical trials using genomic convenience samples. To discuss the extent of imbalance, confounding, bias, design efficiency loss, type I error, and type II error that can occur in the evaluation of the convenience samples, particularly when they are small samples. To articulate statistical considerations for a reasonable sample size to minimize the chance of imbalance, and, to highlight the importance of replicating the subgroup finding in independent studies. Four case examples reflecting recent regulatory experiences are used to underscore the problems with convenience samples. Probability of imbalance for a pre-specified subgroup is provided to elucidate sample size needed to minimize the chance of imbalance. We use an example drug development to highlight the level of scientific rigor needed, with evidence replicated for a pre-specified subgroup claim. The convenience samples evaluated ranged from 18% to 38% of the intent-to-treat samples with sample size ranging from 100 to 5000 patients per arm. The baseline imbalance can occur with probability higher than 25%. Mild to moderate multiple confounders yielding the same directional bias in favor of the treated group can make treatment group incomparable at baseline and result in a false positive conclusion that there is a treatment difference. Conversely, if the same directional bias favors the placebo group or there is loss in design efficiency, the type II error can increase substantially. Pre-specification of a genomic subgroup hypothesis is useful only for some degree of type I error control. Complete ascertainment of genomic samples in a randomized controlled trial should be the first step to explore if a favorable genomic patient subgroup suggests a treatment effect when there is no clear prior knowledge and understanding about how the mechanism of a drug target affects the clinical outcome of interest. When stratified randomization based on genomic biomarker status cannot be implemented in designing a pharmacogenomics confirmatory clinical trial, if there is one genomic biomarker prognostic for clinical response, as a general rule of thumb, a sample size of at least 100 patients may be needed to be considered for the lower prevalence genomic subgroup to minimize the chance of an imbalance of 20% or more difference in the prevalence of the genomic marker. The sample size may need to be at least 150, 350, and 1350, respectively, if an imbalance of 15%, 10% and 5% difference is of concern.

Probability of coincidental similarity among the orbits of small bodies - I. Pairing

NASA Astrophysics Data System (ADS)

Jopek, Tadeusz Jan; Bronikowska, Małgorzata

2017-09-01

Probability of coincidental clustering among orbits of comets, asteroids and meteoroids depends on many factors like: the size of the orbital sample searched for clusters or the size of the identified group, it is different for groups of 2,3,4,… members. Probability of coincidental clustering is assessed by the numerical simulation, therefore, it depends also on the method used for the synthetic orbits generation. We have tested the impact of some of these factors. For a given size of the orbital sample we have assessed probability of random pairing among several orbital populations of different sizes. We have found how these probabilities vary with the size of the orbital samples. Finally, keeping fixed size of the orbital sample we have shown that the probability of random pairing can be significantly different for the orbital samples obtained by different observation techniques. Also for the user convenience we have obtained several formulae which, for given size of the orbital sample can be used to calculate the similarity threshold corresponding to the small value of the probability of coincidental similarity among two orbits.

Men who have sex with men in Great Britain: comparing methods and estimates from probability and convenience sample surveys

PubMed Central

Prah, Philip; Hickson, Ford; Bonell, Chris; McDaid, Lisa M; Johnson, Anne M; Wayal, Sonali; Clifton, Soazig; Sonnenberg, Pam; Nardone, Anthony; Erens, Bob; Copas, Andrew J; Riddell, Julie; Weatherburn, Peter; Mercer, Catherine H

2016-01-01

Objective To examine sociodemographic and behavioural differences between men who have sex with men (MSM) participating in recent UK convenience surveys and a national probability sample survey. Methods We compared 148 MSM aged 18–64 years interviewed for Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) undertaken in 2010–2012, with men in the same age range participating in contemporaneous convenience surveys of MSM: 15 500 British resident men in the European MSM Internet Survey (EMIS); 797 in the London Gay Men's Sexual Health Survey; and 1234 in Scotland's Gay Men's Sexual Health Survey. Analyses compared men reporting at least one male sexual partner (past year) on similarly worded questions and multivariable analyses accounted for sociodemographic differences between the surveys. Results MSM in convenience surveys were younger and better educated than MSM in Natsal-3, and a larger proportion identified as gay (85%–95% vs 62%). Partner numbers were higher and same-sex anal sex more common in convenience surveys. Unprotected anal intercourse was more commonly reported in EMIS. Compared with Natsal-3, MSM in convenience surveys were more likely to report gonorrhoea diagnoses and HIV testing (both past year). Differences between the samples were reduced when restricting analysis to gay-identifying MSM. Conclusions National probability surveys better reflect the population of MSM but are limited by their smaller samples of MSM. Convenience surveys recruit larger samples of MSM but tend to over-represent MSM identifying as gay and reporting more sexual risk behaviours. Because both sampling strategies have strengths and weaknesses, methods are needed to triangulate data from probability and convenience surveys. PMID:26965869

An Optimized Small Tissue Handling System for Immunohistochemistry and In Situ Hybridization

PubMed Central

Anthony, Giovanni; Lee, Ju-Ahng

2016-01-01

Recent development in 3D printing technology has opened an exciting possibility for manufacturing 3D devices on one’s desktop. We used 3D modeling programs to design 3D models of a tissue-handling system and these models were “printed” in a stereolithography (SLA) 3D printer to create precision histology devices that are particularly useful to handle multiple samples with small dimensions in parallel. Our system has been successfully tested for in situ hybridization of zebrafish embryos. Some of the notable features include: (1) A conveniently transferrable chamber with 6 mesh-bottomed wells, each of which can hold dozens of zebrafish embryos. This design allows up to 6 different samples to be treated per chamber. (2) Each chamber sits in a well of a standard 6-well tissue culture plate. Thus, up to 36 different samples can be processed in tandem using a single 6 well plate. (3) Precisely fitting lids prevent solution evaporation and condensation, even at high temperatures for an extended period of time: i.e., overnight riboprobe hybridization. (4) Flat bottom mesh maximizes the consistent treatment of individual tissue samples. (5) A magnet-based lifter was created to handle up to 6 chambers (= 36 samples) in unison. (6) The largely transparent resin aids in convenient visual inspection both with eyes and using a stereomicroscope. (7) Surface engraved labeling enables an accurate tracking of different samples. (8) The dimension of wells and chambers minimizes the required amount of precious reagents. (9) Flexible parametric modeling enables an easy redesign of the 3D models to handle larger or more numerous samples. Precise dimensions of 3D models and demonstration of how we use our devices in whole mount in situ hybridization are presented. We also provide detailed information on the modeling software, 3D printing tips, as well as 3D files that can be used with any 3D printer. PMID:27489962

Longitudinal Associations Between Observed and Perceived Neighborhood Food Availability and Body Mass Index in a Multiethnic Urban Sample.

PubMed

Zenk, Shannon N; Mentz, Graciela; Schulz, Amy J; Johnson-Lawrence, Vicki; Gaines, Causandra R

2017-02-01

Blacks, Hispanics, and women of lower socioeconomic status tend to have a higher risk of obesity. Numerous studies over the past decade examined the role of the neighborhood food environment in body weight. However, few were longitudinal. This longitudinal study examined whether multiple measures of neighborhood food availability were associated with body mass index (BMI) in a predominately Black and Hispanic adult sample living in low- to moderate-income urban neighborhoods. This longitudinal study used two waves of data (2002, 2008), including interviewer-measured height and weight, from a community survey of adults ( n = 219). In both 2002 and 2008, multiple measures characterized neighborhood food availability: GIS-derived availability of retail food outlets (large grocery store, small grocery store, convenience store, liquor stores), observed fruit and vegetable availability (count of stores selling 10 or more fresh fruit or vegetable varieties), and perceived fruit and vegetable access. Random intercept models estimated multivariable associations, controlling for individual-level demographics and neighborhood median household income. Small grocery store availability was associated with 1.22-unit increase in BMI ( p = .047), while each unit increase in perceived fruit and vegetable access was associated with a 0.69-unit decrease in BMI ( p = .055). BMI was not associated with large grocery store, convenience store, or liquor store availability, or with observed fruit and vegetable availability. Findings suggest that improving the neighborhood food environment, particularly at small grocery stores, may help urban residents living in low- to moderate-income neighborhoods achieve healthier body weights over time.

Analyzing Feedback Control Systems

NASA Technical Reports Server (NTRS)

Bauer, Frank H.; Downing, John P.

1987-01-01

Interactive controls analysis (INCA) program developed to provide user-friendly environment for design and analysis of linear control systems, primarily feedback control. Designed for use with both small- and large-order systems. Using interactive-graphics capability, INCA user quickly plots root locus, frequency response, or time response of either continuous-time system or sampled-data system. Configuration and parameters easily changed, allowing user to design compensation networks and perform sensitivity analyses in very convenient manner. Written in Pascal and FORTRAN.

A random cluster survey and a convenience sample give comparable estimates of immunity to vaccine preventable diseases in children of school age in Victoria, Australia.

PubMed

Kelly, Heath; Riddell, Michaela A; Gidding, Heather F; Nolan, Terry; Gilbert, Gwendolyn L

2002-08-19

We compared estimates of the age-specific population immunity to measles, mumps, rubella, hepatitis B and varicella zoster viruses in Victorian school children obtained by a national sero-survey, using a convenience sample of residual sera from diagnostic laboratories throughout Australia, with those from a three-stage random cluster survey. When grouped according to school age (primary or secondary school) there was no significant difference in the estimates of immunity to measles, mumps, hepatitis B or varicella. Compared with the convenience sample, the random cluster survey estimated higher immunity to rubella in samples from both primary (98.7% versus 93.6%, P = 0.002) and secondary school students (98.4% versus 93.2%, P = 0.03). Despite some limitations, this study suggests that the collection of a convenience sample of sera from diagnostic laboratories is an appropriate sampling strategy to provide population immunity data that will inform Australia's current and future immunisation policies. Copyright 2002 Elsevier Science Ltd.

Men who have sex with men in Great Britain: comparing methods and estimates from probability and convenience sample surveys.

PubMed

Prah, Philip; Hickson, Ford; Bonell, Chris; McDaid, Lisa M; Johnson, Anne M; Wayal, Sonali; Clifton, Soazig; Sonnenberg, Pam; Nardone, Anthony; Erens, Bob; Copas, Andrew J; Riddell, Julie; Weatherburn, Peter; Mercer, Catherine H

2016-09-01

To examine sociodemographic and behavioural differences between men who have sex with men (MSM) participating in recent UK convenience surveys and a national probability sample survey. We compared 148 MSM aged 18-64 years interviewed for Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) undertaken in 2010-2012, with men in the same age range participating in contemporaneous convenience surveys of MSM: 15 500 British resident men in the European MSM Internet Survey (EMIS); 797 in the London Gay Men's Sexual Health Survey; and 1234 in Scotland's Gay Men's Sexual Health Survey. Analyses compared men reporting at least one male sexual partner (past year) on similarly worded questions and multivariable analyses accounted for sociodemographic differences between the surveys. MSM in convenience surveys were younger and better educated than MSM in Natsal-3, and a larger proportion identified as gay (85%-95% vs 62%). Partner numbers were higher and same-sex anal sex more common in convenience surveys. Unprotected anal intercourse was more commonly reported in EMIS. Compared with Natsal-3, MSM in convenience surveys were more likely to report gonorrhoea diagnoses and HIV testing (both past year). Differences between the samples were reduced when restricting analysis to gay-identifying MSM. National probability surveys better reflect the population of MSM but are limited by their smaller samples of MSM. Convenience surveys recruit larger samples of MSM but tend to over-represent MSM identifying as gay and reporting more sexual risk behaviours. Because both sampling strategies have strengths and weaknesses, methods are needed to triangulate data from probability and convenience surveys. 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/

The first liquid biopsy test approved. Is it a new era of mutation testing for non-small cell lung cancer?

PubMed Central

2017-01-01

Specific mutations in epidermal growth factor receptor (EGFR) gene are predictive for response to the EGFR tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer patients (NSCLC). According to international guidelines, the molecular testing in patients with advanced NSCLC of a non-squamous subtype is recommended. However, obtain a tissue sample could be challenging. Liquid biopsy allows to determine patients suitable for EGFR-targeted therapy by analysis of circulating-free tumor DNA (cfDNA) in peripheral blood samples and might replace tissue biopsy. It allows to acquire a material in convenient minimally invasive manner, is easily repeatable, could be used for molecular identification and molecular changes monitoring. Many studies show a high concordance rate between tissue and plasma samples testing. When U.S. Food and Drug Administration (FDA) approved the first liquid biopsy test, analysis of driver gene mutation from cfDNA becomes a reality in clinical practice for patients with NSCLC. PMID:28251125

Representativeness of two sampling procedures for an internet intervention targeting cancer-related distress: a comparison of convenience and registry samples.

PubMed

Owen, Jason E; Bantum, Erin O'Carroll; Criswell, Kevin; Bazzo, Julie; Gorlick, Amanda; Stanton, Annette L

2014-08-01

Internet interventions often rely on convenience sampling, yet convenience samples may differ in important ways from systematic recruitment approaches. The purpose of this study was to evaluate potential demographic, medical, and psychosocial differences between Internet-recruited and registry-recruited cancer survivors in an Internet-based intervention. Participants were recruited from a cancer registry (n = 80) and via broad Internet outreach efforts (n = 160). Participants completed a set of self-report questionnaires, and both samples were compared to a population-based sample of cancer survivors (n = 5,150). The Internet sample was younger, better educated, more likely to be female, had longer time since diagnosis, and had more advanced stage of disease (p's < .001), and the registry-sample was over-represented by men and those with prostate or other cancer types (p's < .001). The Internet sample also exhibited lower quality of life and social support and greater mood disturbance (p's < .001). Understanding how convenience and systematic samples differ has important implications for external validity and potential for dissemination of Internet-based interventions.

Cultural definitions of elder maltreatment in Portugal.

PubMed

Mercurio, Andrea E; Nyborn, Justin

2006-01-01

A small convenience sample of 34 participants (17 males, 17 females) from the Portuguese islands of the Azores and Madeira were asked to provide examples of how extreme, moderate, and mild maltreatment towards an elder would be defined in their culture and society. Neglect, especially psychological neglect, physical maltreatment, and psychological maltreatment were the most frequently reported types of maltreatment. References to neglect and physical maltreatment appeared most often as examples of extreme maltreatment. In general, men were somewhat more likely than women to provide examples of physical aggression in their examples of maltreatment. As examples of extreme maltreatment, females provided significantly more examples of abandonment than males. Although interpretations of the findings must be cautious because of the small sample size and limited statistical power, the study illustrates a procedure for assessing constructs of elder mistreatment in a way that attends to respondents' own constructions of the phenomenon.

The importance of aquaculture community group (ACG) in social media (Facebook) towards the aquaculture knowledge and financial improvement of small scale fish farmers (SSFF) in rural areas of Central Java

NASA Astrophysics Data System (ADS)

Elfitasari, T.; Nugroho, R. A.; Nugroho, A. P.

2018-04-01

Internet is now widely used by people all over the world, including small scale fisheries communities such as fish farmers. Many applications are being created including social media Facebook which are used by small scale fish farmers (SSFF) for its ease and convenience. The objective of this research is to identify the impact of aquaculture community group (ACG) in social media Facebook towards the improvement of aquaculture knowledge and financial condition of small scale fish farmers in Central Java. This research used quantitative approach where questionnaires were distributed into two groups: SSFF who are member of ACG in social media Facebook and who are not. Sampling technique used random sampling, used 60 samples of SSFF in Central Java. Data obtained were tested using the test statistic Independent t-test using SPSS v.20. Result showed a significant effect of group who are member of ACG in social media Facebook and those who are not, towards the aquaculture knowledge (t count -7.424 and sig 0.000) and financial improvement (t -3.775 and sig 0.000). The results of the average value of the SSFF who are ACG member in Facebook are also higher than farmers who are not.

Integrating quantitative PCR and Bayesian statistics in quantifying human adenoviruses in small volumes of source water.

PubMed

Wu, Jianyong; Gronewold, Andrew D; Rodriguez, Roberto A; Stewart, Jill R; Sobsey, Mark D

2014-02-01

Rapid quantification of viral pathogens in drinking and recreational water can help reduce waterborne disease risks. For this purpose, samples in small volume (e.g. 1L) are favored because of the convenience of collection, transportation and processing. However, the results of viral analysis are often subject to uncertainty. To overcome this limitation, we propose an approach that integrates Bayesian statistics, efficient concentration methods, and quantitative PCR (qPCR) to quantify viral pathogens in water. Using this approach, we quantified human adenoviruses (HAdVs) in eighteen samples of source water collected from six drinking water treatment plants. HAdVs were found in seven samples. In the other eleven samples, HAdVs were not detected by qPCR, but might have existed based on Bayesian inference. Our integrated approach that quantifies uncertainty provides a better understanding than conventional assessments of potential risks to public health, particularly in cases when pathogens may present a threat but cannot be detected by traditional methods. © 2013 Elsevier B.V. All rights reserved.

Detection of an amphiphilic biosample in a paper microchannel based on length.

PubMed

Chen, Yu-Tzu; Yang, Jing-Tang

2015-01-01

We developed a simple method to achieve semiquantitative detection of an amphiphilic biosample through measuring the length of flow on a microfluidic analytical device (μPAD) based on paper. When an amphiphilic sample was dripped into a straight microchannel defined with a printed wax barrier (hydrophobic) on filter paper (hydrophilic), the length of flow was affected by the reciprocal effect between the sample, the filter-paper channel and the wax barrier. The flow length decreased with increasing concentration of an amphiphilic sample because of adsorption of the sample on the hydrophobic barrier. Measurement of the flow length enabled a determination of the concentration of the amphiphilic sample. The several tested samples included surfactants (Tween 20 and Triton X-100), oligonucleotides (DNA), bovine serum albumin (BSA), human albumin, nitrite, glucose and low-density lipoprotein (LDL). The results show that the measurement of the flow length determined directly the concentration of an amphiphilic sample, whereas a non-amphiphilic sample was not amenable to this method. The proposed method features the advantages of small cost, simplicity, convenience, directness, rapidity (<5 min) and requirement of only a small volume (5 μL) of sample, with prospective applications in developing areas and sites near patients for testing at a point of care (POCT).

Influence of population versus convenience sampling on sample characteristics in studies of cognitive aging.

PubMed

Brodaty, Henry; Mothakunnel, Annu; de Vel-Palumbo, Melissa; Ames, David; Ellis, Kathryn A; Reppermund, Simone; Kochan, Nicole A; Savage, Greg; Trollor, Julian N; Crawford, John; Sachdev, Perminder S

2014-01-01

We examined whether differences in findings of studies examining mild cognitive impairment (MCI) were associated with recruitment methods by comparing sample characteristics in two contemporaneous Australian studies, using population-based and convenience sampling. The Sydney Memory and Aging Study invited participants randomly from the electoral roll in defined geographic areas in Sydney. The Australian Imaging, Biomarkers and Lifestyle Study of Ageing recruited cognitively normal (CN) individuals via media appeals and MCI participants via referrals from clinicians in Melbourne and Perth. Demographic and cognitive variables were harmonized, and similar diagnostic criteria were applied to both samples retrospectively. CN participants recruited via convenience sampling were younger, better educated, more likely to be married and have a family history of dementia, and performed better cognitively than those recruited via population-based sampling. MCI participants recruited via population-based sampling had better memory performance and were less likely to carry the apolipoprotein E ε4 allele than clinically referred participants but did not differ on other demographic variables. A convenience sample of normal controls is likely to be younger and better functioning and that of an MCI group likely to perform worse than a purportedly random sample. Sampling bias should be considered when interpreting findings. Copyright © 2014 Elsevier Inc. All rights reserved.

Quality of artemisinin-based combination formulations for malaria treatment: prevalence and risk factors for poor quality medicines in public facilities and private sector drug outlets in Enugu, Nigeria.

PubMed

Kaur, Harparkash; Allan, Elizabeth Louise; Mamadu, Ibrahim; Hall, Zoe; Ibe, Ogochukwu; El Sherbiny, Mohamed; van Wyk, Albert; Yeung, Shunmay; Swamidoss, Isabel; Green, Michael D; Dwivedi, Prabha; Culzoni, Maria Julia; Clarke, Siân; Schellenberg, David; Fernández, Facundo M; Onwujekwe, Obinna

2015-01-01

Artemisinin-based combination therapies are recommended by the World Health Organisation (WHO) as first-line treatment for Plasmodium falciparum malaria, yet medication must be of good quality for efficacious treatment. A recent meta-analysis reported 35% (796/2,296) of antimalarial drug samples from 21 Sub-Saharan African countries, purchased from outlets predominantly using convenience sampling, failed chemical content analysis. We used three sampling strategies to purchase artemisinin-containing antimalarials (ACAs) in Enugu metropolis, Nigeria, and compared the resulting quality estimates. ACAs were purchased using three sampling approaches--convenience, mystery clients and overt, within a defined area and sampling frame in Enugu metropolis. The active pharmaceutical ingredients were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories. Results were expressed as percentage of APIs stated on the packaging and used to categorise each sample as acceptable quality, substandard, degraded, or falsified. Content analysis of 3024 samples purchased from 421 outlets using convenience (n=200), mystery (n=1,919) and overt (n=905) approaches, showed overall 90.8% ACAs to be of acceptable quality, 6.8% substandard, 1.3% degraded and 1.2% falsified. Convenience sampling yielded a significantly higher prevalence of poor quality ACAs, but was not evident by the mystery and overt sampling strategies both of which yielded results that were comparable between each other. Artesunate (n=135; 4 falsified) and dihydroartemisinin (n=14) monotherapy tablets, not recommended by WHO, were also identified. Randomised sampling identified fewer falsified ACAs than previously reported by convenience approaches. Our findings emphasise the need for specific consideration to be given to sampling frame and sampling approach if representative information on drug quality is to be obtained.

Food-purchasing patterns for home: a grocery store-intercept survey.

PubMed

Yoo, Sunmi; Baranowski, Tom; Missaghian, Mariam; Baranowski, Janice; Cullen, Karen; Fisher, Jennifer O; Watson, Kathy; Zakeri, Issa F; Nicklas, Theresa

2006-05-01

To identify the most common frequency of food-purchasing patterns and relate this pattern to characteristics of individuals and families. A customer-intercept survey was conducted in the greater Houston area, Texas, USA, in 2002. The frequency of food shopping at supermarkets, convenience stores and restaurants to buy food for eating at home was assessed. A total of 823 adults (78.5% female; mean age 37.4 years) who went to any of several grocery or convenience stores, including European, Hispanic and African Americans, and Asian/Pacific Islanders. Major food-shopping patterns were a weekly big trip with a few small trips (34.9%), biweekly big trips with a few small trips (21.9%), no big shopping trips (15.4%), a weekly big trip without small trips (13.9%), a monthly big trip (8.3%), and biweekly big trips without small trips (6.4%). While 61.1% of participants never went to convenience stores to buy fruit and vegetables (F&V) for eating at home, 67% went to restaurants for F&V. African American families shopped for food least frequently, while Asian American families shopped for food most frequently. Educational level was negatively associated with the use of convenience stores and positively associated with take-away from restaurants. There is substantial variability in the frequency of food shopping. Future research on food shopping should incorporate this variable.

Correlation between structural and transport properties of electron beam irradiated PrMnO3 compounds

NASA Astrophysics Data System (ADS)

Christopher, Benedict; Rao, Ashok; Nagaraja, B. S.; Shyam Prasad, K.; Okram, G. S.; Sanjeev, Ganesh; Petwal, Vikash Chandra; Verma, Vijay Pal; Dwivedi, Jishnu; Poornesh, P.

2018-02-01

The structural, electrical, magnetic, and thermal properties of electron beam (EB) irradiated PrMnO3 manganites were investigated in the present communication. X-ray diffraction data reveals that all samples are single phased with orthorhombic distorted structure (Pbnm). Furthermore, the diffracted data are analyzed in detail using Rietveld refinement technique. It is observed that the EB dosage feebly disturbs the MnO6 octahedra. The electrical resistivity of all the samples exhibits semiconducting behavior. Small polaron hopping model is conveniently employed to investigate the semiconducting nature of the pristine as well as EB irradiated samples. The Seebeck coefficient (S) of the pristine as well as the irradiated samples exhibit large positive values at lower temperatures, signifying holes as the dominant charge carriers. The analysis of Seebeck coefficient data confirms that the small polaron hopping mechanism assists the thermoelectric transport property in the high temperature region. The magnetic measurements confirm the existence of paramagnetic (PM) to ferromagnetic (FM) behavior for the pristine and irradiated samples. In the lower temperature regime, coexistence of FM clusters and AFM matrix is dominating. Thus, the complex magnetic behavior of the compound has been explained in terms of rearrangement of antiferromagnetically coupled ionic moments.

Sampling studies to estimate the HIV prevalence rate in female commercial sex workers.

PubMed

Pascom, Ana Roberta Pati; Szwarcwald, Célia Landmann; Barbosa Júnior, Aristides

2010-01-01

We investigated sampling methods being used to estimate the HIV prevalence rate among female commercial sex workers. The studies were classified according to the adequacy or not of the sample size to estimate HIV prevalence rate and according to the sampling method (probabilistic or convenience). We identified 75 studies that estimated the HIV prevalence rate among female sex workers. Most of the studies employed convenience samples. The sample size was not adequate to estimate HIV prevalence rate in 35 studies. The use of convenience sample limits statistical inference for the whole group. It was observed that there was an increase in the number of published studies since 2005, as well as in the number of studies that used probabilistic samples. This represents a large advance in the monitoring of risk behavior practices and HIV prevalence rate in this group.

Risk in pediatric anesthesia.

PubMed

Paterson, Neil; Waterhouse, Peter

2011-08-01

Risk in pediatric anesthesia can be conveniently classified as minor or major. Major morbidity includes cardiac arrest, brain damage and death. Minor morbidity can be assessed by clinical audits with small patient samples. Major morbidity is rare. It is best assessed by very large clinical studies and by review of closed malpractice claims. Both minor and major morbidity occur most commonly in infants and children under three, especially those with severe co-morbidities. Knowledge of risk profiles in pediatric anesthesia is a starting point for the reduction of risk. © 2010 Blackwell Publishing Ltd.

Perceptions of antimicrobial usage, antimicrobial resistance and policy measures to reduce antimicrobial usage in convenient samples of Belgian, French, German, Swedish and Swiss pig farmers.

PubMed

Visschers, V H M; Backhans, A; Collineau, L; Iten, D; Loesken, S; Postma, M; Belloc, C; Dewulf, J; Emanuelson, U; Beilage, E Grosse; Siegrist, M; Sjölund, M; Stärk, K D C

2015-04-01

We conducted a survey among convenient samples of pig farmers (N=281) in Belgium, France, Germany, Sweden and Switzerland. We identified some significant differences among the five investigated countries (independent variable) regarding farmers' antimicrobial usage compared to their own country and worries related to pig farming (dependent variables), but most of the differences were rather small. In general, farmers perceived their own antimicrobial usage to be lower than that of their peers in the same country and lower than or similar to that of farmers from other countries. This may be a consequence of our convenience sample, resulting in self-selection of highly motivated farmers. Farmers were significantly more worried about financial/legal issues than about antimicrobial resistance. They believed that a reduction in revenues for slaughter pigs treated with a large amount of antimicrobials would have the most impact on reduced antimicrobial usage in their country. Further, farmers who were more worried about antimicrobial resistance and who estimated their own antimicrobial usage as lower than their fellow countrymen, perceived more impact from policy measures on the reduction of antimicrobials. Our results indicated that the same policy measures can be applied to reduce antimicrobial usage in pig farming in all five countries. Moreover, it seems worthwhile to increase pig farmers' awareness of the threat of antimicrobial resistance and its relation to antimicrobial usage; not only because pig farmers appeared little worried about antimicrobial usage but also because it affected farmers' perception of policy measures to reduce antimicrobial usage. Our samples were not representative for the national pig farmer populations. Further research is therefore needed to examine to what extent our findings can be generalised to these populations and to farmers in other countries. Copyright © 2015 Elsevier B.V. All rights reserved.

Prevalence of paratuberculosis in the dairy goat and dairy sheep industries in Ontario, Canada.

PubMed

Bauman, Cathy A; Jones-Bitton, Andria; Menzies, Paula; Toft, Nils; Jansen, Jocelyn; Kelton, David

2016-02-01

A cross-sectional study was undertaken (October 2010 to August 2011) to estimate the prevalence of paratuberculosis in the small ruminant dairy industries in Ontario, Canada. Blood and feces were sampled from 580 goats and 397 sheep (lactating and 2 y of age or older) that were randomly selected from 29 randomly selected dairy goat herds and 21 convenience-selected dairy sheep flocks. Fecal samples were analyzed using bacterial culture (BD BACTEC MGIT 960) and polymerase chain reaction (Tetracore); serum samples were tested with the Prionics Parachek enzyme-linked immunosorbent assay (ELISA). Using 3-test latent class Bayesian models, true farm-level prevalence was estimated to be 83.0% [95% probability interval (PI): 62.6% to 98.1%] for dairy goats and 66.8% (95% PI: 41.6% to 91.4%) for dairy sheep. The within-farm true prevalence for dairy goats was 35.2% (95% PI: 23.0% to 49.8%) and for dairy sheep was 48.3% (95% PI: 27.6% to 74.3%). These data indicate that a paratuberculosis control program for small ruminants is needed in Ontario.

The physical and microbiological quality of chicken meat in the different type of enterprise poultry slaughterhouse: a case study in Karanganyar District

NASA Astrophysics Data System (ADS)

Hertanto, B. S.; Nurmalasari, C. D. A.; Nuhriawangsa, A. M. P.; Cahyadi, M.; Kartikasari, L. R.

2018-01-01

The aim of this study was to determine the physical and microbiological quality of chicken meat produced by the different type of enterprise slaughterhouse in Karanganyar District. The number of 20 poultry slaughterhouses was determined by convenience sampling method. The samples of chicken meat were randomly collected from medium enterprise poultry slaughterhouses (n=12) and small enterprise poultry slaughterhouses (n=8). A survey was carried out among poultry slaughterhouses in Karanganyar District. All the samples were subjected to physical quality consisted of pH test, texture, and color, while microbiological quality consisted of total plate count, microbial detection of Escherichia coli and Salmonella. The data were analyzed using descriptive quantitative analysis. The study showed that chicken meat in 6 small enterprise slaughterhouses and 11 medium enterprise slaughterhouses had normal pH of 5.81 - 6.3. Color and texture of chicken meats had relatively normal in both small and medium enterprise slaughterhouses. The total plate count of chicken meat showed in both small and medium enterprise slaughterhouses was <1x106 CFU/gr. The test of bacterial contamination showed that 3 of small and medium enterprise slaughterhouses were positively contaminated by Escherichia coli of >1x101 CFU/gr, and Salmonella was detected in 1 medium enterprise slaughterhouse. The overall results of the study suggest that the potential risk of chicken meat contamination depends on the processing of chicken meat in poultry slaughterhouses.

Small Body GN and C Research Report: G-SAMPLE - An In-Flight Dynamical Method for Identifying Sample Mass [External Release Version

NASA Technical Reports Server (NTRS)

Carson, John M., III; Bayard, David S.

2006-01-01

G-SAMPLE is an in-flight dynamical method for use by sample collection missions to identify the presence and quantity of collected sample material. The G-SAMPLE method implements a maximum-likelihood estimator to identify the collected sample mass, based on onboard force sensor measurements, thruster firings, and a dynamics model of the spacecraft. With G-SAMPLE, sample mass identification becomes a computation rather than an extra hardware requirement; the added cost of cameras or other sensors for sample mass detection is avoided. Realistic simulation examples are provided for a spacecraft configuration with a sample collection device mounted on the end of an extended boom. In one representative example, a 1000 gram sample mass is estimated to within 110 grams (95% confidence) under realistic assumptions of thruster profile error, spacecraft parameter uncertainty, and sensor noise. For convenience to future mission design, an overall sample-mass estimation error budget is developed to approximate the effect of model uncertainty, sensor noise, data rate, and thrust profile error on the expected estimate of collected sample mass.

Quality of Artemisinin-Based Combination Formulations for Malaria Treatment: Prevalence and Risk Factors for Poor Quality Medicines in Public Facilities and Private Sector Drug Outlets in Enugu, Nigeria

PubMed Central

Kaur, Harparkash; Allan, Elizabeth Louise; Mamadu, Ibrahim; Hall, Zoe; Ibe, Ogochukwu; El Sherbiny, Mohamed; van Wyk, Albert; Yeung, Shunmay; Swamidoss, Isabel; Green, Michael D.; Dwivedi, Prabha; Culzoni, Maria Julia; Clarke, Siân; Schellenberg, David; Fernández, Facundo M.; Onwujekwe, Obinna

2015-01-01

Background Artemisinin-based combination therapies are recommended by the World Health Organisation (WHO) as first-line treatment for Plasmodium falciparum malaria, yet medication must be of good quality for efficacious treatment. A recent meta-analysis reported 35% (796/2,296) of antimalarial drug samples from 21 Sub-Saharan African countries, purchased from outlets predominantly using convenience sampling, failed chemical content analysis. We used three sampling strategies to purchase artemisinin-containing antimalarials (ACAs) in Enugu metropolis, Nigeria, and compared the resulting quality estimates. Methods ACAs were purchased using three sampling approaches - convenience, mystery clients and overt, within a defined area and sampling frame in Enugu metropolis. The active pharmaceutical ingredients were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories. Results were expressed as percentage of APIs stated on the packaging and used to categorise each sample as acceptable quality, substandard, degraded, or falsified. Results Content analysis of 3024 samples purchased from 421 outlets using convenience (n=200), mystery (n=1,919) and overt (n=905) approaches, showed overall 90.8% ACAs to be of acceptable quality, 6.8% substandard, 1.3% degraded and 1.2% falsified. Convenience sampling yielded a significantly higher prevalence of poor quality ACAs, but was not evident by the mystery and overt sampling strategies both of which yielded results that were comparable between each other. Artesunate (n=135; 4 falsified) and dihydroartemisinin (n=14) monotherapy tablets, not recommended by WHO, were also identified. Conclusion Randomised sampling identified fewer falsified ACAs than previously reported by convenience approaches. Our findings emphasise the need for specific consideration to be given to sampling frame and sampling approach if representative information on drug quality is to be obtained. PMID:26018221

End-of-Life Preferences: A Theory-Driven Inventory

ERIC Educational Resources Information Center

Bonin-Scaon, Sylvie; Munoz Sastre, Maria Teresa; Chasseigne, Gerard; Sorum, Paul C.; Mullet, Etienne

2009-01-01

The study aimed at making a theory-driven inventory of end-of-life preferences. Participants were asked about a variety of preferences representing all eight motivational states described in Apter's Metamotivational Theory (AMT; Apter, 2001). Data from a convenience sample of 965 community participants and a convenience sample of 81 persons…

Devices for SRF material characterization

DOE PAGES

Goudket, Philippe; Xiao, B.; Junginger, T.

2016-10-07

The surface resistance Rs of superconducting materials can be obtained by measuring the quality factor of an elliptical cavity excited in a transverse magnetic mode (TM010). The value obtained has however to be taken as averaged over the whole surface. A more convenient way to obtain Rs, especially of materials which are not yet technologically ready for cavity production, is to measure small samples instead. These can be easily man ufactured at low cost, duplicated and placed in film deposition and surface analytical tools. A commonly used design for a device to measure Rs consists of a cylindrical cavity excitedmore » in a transverse electric (TE110) mode with the sample under test serving as one replaceable endplate. Such a cavity has two drawbacks. For reasonably small samples the resonant frequency will be larger than frequencies of interest concerning SRF application and it requires a reference sample of known Rs. In this article we review several devices which have been designed to overcome these limitations, reaching sub - nΩ resolution in some cases. Some of these devices also comprise a parameter space in frequency and temperature which is inaccessible to standard cavity tests, making them ideal tools to test theoretical surface resistance models.« less

Devices for SRF material characterization

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

Goudket, Philippe; Xiao, B.; Junginger, T.

The surface resistance Rs of superconducting materials can be obtained by measuring the quality factor of an elliptical cavity excited in a transverse magnetic mode (TM010). The value obtained has however to be taken as averaged over the whole surface. A more convenient way to obtain Rs, especially of materials which are not yet technologically ready for cavity production, is to measure small samples instead. These can be easily man ufactured at low cost, duplicated and placed in film deposition and surface analytical tools. A commonly used design for a device to measure Rs consists of a cylindrical cavity excitedmore » in a transverse electric (TE110) mode with the sample under test serving as one replaceable endplate. Such a cavity has two drawbacks. For reasonably small samples the resonant frequency will be larger than frequencies of interest concerning SRF application and it requires a reference sample of known Rs. In this article we review several devices which have been designed to overcome these limitations, reaching sub - nΩ resolution in some cases. Some of these devices also comprise a parameter space in frequency and temperature which is inaccessible to standard cavity tests, making them ideal tools to test theoretical surface resistance models.« less

A prototype splitter apparatus for dividing large catches of small fish

USGS Publications Warehouse

Stapanian, Martin A.; Edwards, William H.

2012-01-01

Due to financial and time constraints, it is often necessary in fisheries studies to divide large samples of fish and estimate total catch from the subsample. The subsampling procedure may involve potential human biases or may be difficult to perform in rough conditions. We present a prototype gravity-fed splitter apparatus for dividing large samples of small fish (30–100 mm TL). The apparatus features a tapered hopper with a sliding and removable shutter. The apparatus provides a comparatively stable platform for objectively obtaining subsamples, and it can be modified to accommodate different sizes of fish and different sample volumes. The apparatus is easy to build, inexpensive, and convenient to use in the field. To illustrate the performance of the apparatus, we divided three samples (total N = 2,000 fish) composed of four fish species. Our results indicated no significant bias in estimating either the number or proportion of each species from the subsample. Use of this apparatus or a similar apparatus can help to standardize subsampling procedures in large surveys of fish. The apparatus could be used for other applications that require dividing a large amount of material into one or more smaller subsamples.

CIHR Candrive Cohort Comparison with Canadian Household Population Holding Valid Driver's Licenses.

PubMed

Gagnon, Sylvain; Marshall, Shawn; Kadulina, Yara; Stinchcombe, Arne; Bédard, Michel; Gélinas, Isabelle; Man-Son-Hing, Malcolm; Mazer, Barbara; Naglie, Gary; Porter, Michelle M; Rapoport, Mark; Tuokko, Holly; Vrkljan, Brenda

2016-06-01

We investigated whether convenience sampling is a suitable method to generate a sample of older drivers representative of the older-Canadian driver population. Using equivalence testing, we compared a large convenience sample of older drivers (Candrive II prospective cohort study) to a similarly aged population of older Canadian drivers. The Candrive sample consists of 928 community-dwelling older drivers from seven metropolitan areas of Canada. The population data was obtained from the Canadian Community Health Survey - Healthy Aging (CCHS-HA), which is a representative sample of older Canadians. The data for drivers aged 70 and older were extracted from the CCHS-HA database, for a total of 3,899 older Canadian drivers. Two samples were demonstrated as equivalent on socio-demographic, health, and driving variables that we compared, but not on driving frequency. We conclude that convenience sampling used in the Candrive study created a fairly representative sample of Canadian older drivers, with a few exceptions.

Sampling and analysis for radon-222 dissolved in ground water and surface water

USGS Publications Warehouse

DeWayne, Cecil L.; Gesell, T.F.

1992-01-01

Radon-222 is a naturally occurring radioactive gas in the uranium-238 decay series that has traditionally been called, simply, radon. The lung cancer risks associated with the inhalation of radon decay products have been well documented by epidemiological studies on populations of uranium miners. The realization that radon is a public health hazard has raised the need for sampling and analytical guidelines for field personnel. Several sampling and analytical methods are being used to document radon concentrations in ground water and surface water worldwide but no convenient, single set of guidelines is available. Three different sampling and analytical methods - bubbler, liquid scintillation, and field screening - are discussed in this paper. The bubbler and liquid scintillation methods have high accuracy and precision, and small analytical method detection limits of 0.2 and 10 pCi/l (picocuries per liter), respectively. The field screening method generally is used as a qualitative reconnaissance tool.

Variational Approach to Enhanced Sampling and Free Energy Calculations

NASA Astrophysics Data System (ADS)

Valsson, Omar; Parrinello, Michele

2014-08-01

The ability of widely used sampling methods, such as molecular dynamics or Monte Carlo simulations, to explore complex free energy landscapes is severely hampered by the presence of kinetic bottlenecks. A large number of solutions have been proposed to alleviate this problem. Many are based on the introduction of a bias potential which is a function of a small number of collective variables. However constructing such a bias is not simple. Here we introduce a functional of the bias potential and an associated variational principle. The bias that minimizes the functional relates in a simple way to the free energy surface. This variational principle can be turned into a practical, efficient, and flexible sampling method. A number of numerical examples are presented which include the determination of a three-dimensional free energy surface. We argue that, beside being numerically advantageous, our variational approach provides a convenient and novel standpoint for looking at the sampling problem.

SRD5A1 genotype frequency differences in women with mild versus severe premenstrual symptoms.

PubMed

Adams, Marlene; McCrone, Susan

2012-02-01

The aims of this small pilot study were to explore the association between premenstrual symptom severity and two genes from the gamma-aminobutyric acid (GABA) pathway: steroid-5-alpha-reductase, alpha polypeptide 1 (SRD5A1) and gamma-aminobutyric acid receptor subunit alpha-4 (GABRA4). Saliva samples were obtained from a convenience sample of 19 Caucasian females ages 18-25 years, ten cases and nine controls. Deoxyribonucleic acid (DNA) was isolated, and genotyping performed on ten single nucleotide polymorphisms (SNPs). Ten percent of cases and 44% of controls had the cytosine/cytosine (C/C) genotype for the SRD5A1 SNP, rs501999 indicating that this genotype may protect women against severe premenstrual symptoms. Replication of this study using an adequately powered sample size is warranted.

Understanding small business engagement in workplace violence prevention programs.

PubMed

Bruening, Rebecca A; Strazza, Karen; Nocera, Maryalice; Peek-Asa, Corinne; Casteel, Carri

2015-01-01

Worksite wellness, safety, and violence prevention programs have low penetration among small, independent businesses. This study examined barriers and strategies influencing small business participation in workplace violence prevention programs (WVPPs). A semistructured interview guide was used in 32 telephone interviews. The study took place at the University of North Carolina Injury Prevention Research Center. Participating were a purposive sample of 32 representatives of small business-serving organizations (e.g., business membership organizations, regulatory agencies, and economic development organizations) selected for their experience with small businesses. This study was designed to inform improved dissemination of Crime Free Business (CFB), a WVPP for small, independent retail businesses. Thematic qualitative data analysis was used to identify key barriers and strategies for promoting programs and services to small businesses. Three key factors that influence small business engagement emerged from the analysis: (1) small businesses' limited time and resources, (2) low salience of workplace violence, (3) influence of informal networks and source credibility. Identified strategies include designing low-cost and convenient programs, crafting effective messages, partnering with influential organizations and individuals, and conducting outreach through informal networks. Workplace violence prevention and public health practitioners may increase small business participation in programs by reducing time and resource demands, addressing small business concerns, enlisting support from influential individuals and groups, and emphasizing business benefits of participating in the program.

An exploratory qualitative study on perceptions about mosquito bed nets in the Niger Delta: what are the barriers to sustained use?

PubMed Central

Galvin, Kathleen T; Petford, Nick; Ajose, Frances; Davies, Dai

2011-01-01

Background: The effectiveness of malaria control programs is determined by an array of complex factors, including the acceptability and sustained use of preventative measures such as the bed net. A small-scale exploratory study was conducted in several locations in the Niger Delta region, Nigeria, to discover barriers against the use of bed nets, in the context of a current drive to scale up net use in Nigeria. Methods: A qualitative approach with a convenience sample was used. One to one interviews with mostly male adult volunteers were undertaken which explored typical living and sleeping arrangements, and perceptions about and barriers against the use of the mosquito prevention bed net. Results: Several key issues emerged from the qualitative data. Bed nets were not reported as widely used in this small sample. The reasons reported for lack of use included issues of convenience, especially net set up and dismantling; potential hazard and safety concerns; issues related to typical family composition and nature of accommodation; humid weather conditions; and perceptions of cost and effectiveness. Most barriers to net use concerned issues about everyday practical living and sleeping arrangements and perceptions about comfort. Interviewees identified were aware of malaria infection risks, but several also indicated certain beliefs that were barriers to net use. Conclusions: Successful control of malaria and scale up of insecticide-treated net coverage relies on community perceptions and practice. This small study has illuminated a number of important everyday life issues, which remain barriers to sustained net use, and has clarified further questions to be considered in net design and in future research studies. The study highlights the need for further research on the human concerns that contribute to sustained use of nets or, conversely, present significant barriers to their use. PMID:21544249

Texas nutrition environment assessment of retail food stores (TxNEA-S): development and evaluation.

PubMed

Gloria, Christian T; Steinhardt, Mary A

2010-11-01

Current nutrition environment instruments are typically designed to measure a small number of healthy foods based on national trends. They lack the depth to accurately measure the unique dietary choices of subpopulations, such as Texas consumers whose food preferences are influenced by Hispanic/Latino culture. Thus the purposes of the present study were to: (i) develop a comprehensive observational tool to measure the availability of healthy foods from retail stores in Texas; and (ii) conduct a pilot test to examine the tool's reliability, as well as differences in the availability of healthy foods in stores between high- and low-income neighbourhoods. Grocery and convenience stores were assessed for availability of healthy foods. Reliability was calculated using percentage agreement, and differences in availability were examined using 2 (store type) × 2 (neighbourhood income) ANOVA. One high-income and one low-income neighbourhood in Austin, Texas. A sample of thirty-eight stores comprising twenty-five convenience stores and thirteen grocery stores. The low-income neighbourhood had 324 % more convenience stores and 56 % fewer grocery stores than the high-income neighbourhood. High inter-rater (mean = 0·95) and test-retest reliability (mean = 0·92) and a significant interaction (P = 0·028) between store type and neighbourhood income were found. The TxNEA-S tool includes 106 healthy food items, such as fruits, vegetables, dairy, proteins and grains. The tool is reliable and face validity is affirmed by the Texas Department of Health. Grocery stores have more healthy foods than convenience stores, and high-income grocery stores offer more healthy foods than low-income grocery stores.

Incidence Study of Spores of Clostridium botulinum in Convenience Foods

PubMed Central

Insalata, N. F.; Witzeman, S. J.; Fredericks, G. J.; Sunga, F. C. A.

1969-01-01

The objective of this study was to gather data on the incidence of Clostridium botulinum spores in selected consumer-convenience food products. The incidence of spores of C. botulinum in 100 samples of each of four categories of commercially available convenience foods was determined. These categories included (i) “boil-in-the-bag” foods, (ii) vacuum-packed foods, (iii) pressurized foods, and (iv) dehydrated and freeze-dried foods. Of the 400 samples analyzed, one was found to contain the spores of C. botulinum. This occurred in vacuum-packed frank-furters and was identified as type B. PMID:4890746

Convenience food in the diet of children and adolescents: consumption and composition.

PubMed

Alexy, Ute; Sichert-Hellert, Wolfgang; Rode, Tabea; Kersting, Mathilde

2008-02-01

Despite an increasing trend towards the use of convenience food, there is to date little debate on it in the nutritional sciences. In the present study, we present and evaluate data on consumption frequencies and composition of savoury convenience food in German families using data from the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study. The DONALD Study is an ongoing, longitudinal (open cohort) study (started 1985), collecting detailed data on diet, development, and metabolism in infants, children and adolescents. Dietary intake was measured by yearly repeated 3 d weighed dietary records (n 1558) in 554 subjects (278 boys; 276 girls), 3-18 years old, between 2003 and 2006. A total of 1345 (86%) 3 d dietary records mentioned consumption of at least one convenience food. Convenience food consumption (percentage of total food intake, g/d) increased with age from approximately 3% in the 3-8 year olds to 7% in 14-18-year-old boys and 5% in 14-18-year-old girls (P < 0.0001) but remained constant during the study period. Convenience foods contributed more to total fat (g/d) (P < 0.001) and less to total carbohydrate (P < 0.0001) than to total energy (kJ/d) intake. The 700 convenience-food products recorded by our sample had on average fourteen ingredients; 4% were flavourings and 16% were food additives. In conclusion, convenience foods were widely consumed by our sample of German children and adolescents and their consumption increased with age. The composition of convenience food was characterised by a high fat content and a high number of flavourings and food additives.

Evaluation of respondent-driven sampling.

PubMed

McCreesh, Nicky; Frost, Simon D W; Seeley, Janet; Katongole, Joseph; Tarsh, Matilda N; Ndunguse, Richard; Jichi, Fatima; Lunel, Natasha L; Maher, Dermot; Johnston, Lisa G; Sonnenberg, Pam; Copas, Andrew J; Hayes, Richard J; White, Richard G

2012-01-01

Respondent-driven sampling is a novel variant of link-tracing sampling for estimating the characteristics of hard-to-reach groups, such as HIV prevalence in sex workers. Despite its use by leading health organizations, the performance of this method in realistic situations is still largely unknown. We evaluated respondent-driven sampling by comparing estimates from a respondent-driven sampling survey with total population data. Total population data on age, tribe, religion, socioeconomic status, sexual activity, and HIV status were available on a population of 2402 male household heads from an open cohort in rural Uganda. A respondent-driven sampling (RDS) survey was carried out in this population, using current methods of sampling (RDS sample) and statistical inference (RDS estimates). Analyses were carried out for the full RDS sample and then repeated for the first 250 recruits (small sample). We recruited 927 household heads. Full and small RDS samples were largely representative of the total population, but both samples underrepresented men who were younger, of higher socioeconomic status, and with unknown sexual activity and HIV status. Respondent-driven sampling statistical inference methods failed to reduce these biases. Only 31%-37% (depending on method and sample size) of RDS estimates were closer to the true population proportions than the RDS sample proportions. Only 50%-74% of respondent-driven sampling bootstrap 95% confidence intervals included the population proportion. Respondent-driven sampling produced a generally representative sample of this well-connected nonhidden population. However, current respondent-driven sampling inference methods failed to reduce bias when it occurred. Whether the data required to remove bias and measure precision can be collected in a respondent-driven sampling survey is unresolved. Respondent-driven sampling should be regarded as a (potentially superior) form of convenience sampling method, and caution is required when interpreting findings based on the sampling method.

The Prevalence of Gambling in College: A Review of Literature, Convenience Sample, and Recommendations

ERIC Educational Resources Information Center

Seifried, Chad; Krenzelok, Ann; Turner, Brian A.; Brett, Martin

2009-01-01

This project examined the level of gambling exhibited by a convenience sample of 155 college students at a large Midwestern university and compared it to previously completed work. The researchers found most college student gamblers engaged in the most popular form of gambling like casino games, card games, and betting pools for money. Gambling on…

Waterpipe tobacco smoking: knowledge, attitudes, beliefs, and behavior in two U.S. samples.

PubMed

Smith-Simone, Stephanie; Maziak, Wasim; Ward, Kenneth D; Eissenberg, Thomas

2008-02-01

Despite evidence of increasing waterpipe tobacco smoking prevalence among U.S. young adults, little is known about the knowledge, attitudes, beliefs, and smoking patterns of waterpipe users in this population. To address this lack of knowledge, two convenience samples of U.S. waterpipe users were surveyed--one from a Richmond, Virginia, waterpipe café (n=101), the other from an Internet forum called HookahForum.com (n=100). Sixty percent reported first-time waterpipe use at or before age 18. Daily waterpipe use was reported by 19%, weekly use by 41%, and monthly use by 29%. Waterpipe use was more common during the weekend (75%) than during weekdays (43%). Forty-four percent reported spending >or=60 min smoking tobacco during a waterpipe session. The majority of waterpipe users owned a waterpipe (57%) and purchased it on the Internet (71%). Many waterpipe users smoked the sweetened and flavored tobacco (i.e., maassel), and fruit flavors were the most popular (54%). Past month use of cigarettes, tobacco products other than cigarettes or waterpipe, and alcohol was 54%, 33%, and 80% respectively, and 36% reported past-month marijuana use. Most waterpipe users were confident about their ability to quit (96%), but only a minority (32%) intended to quit. Most waterpipe users believed waterpipe tobacco smoking was less harmful and addictive than cigarettes. These results are from small convenience samples; more detailed study of a larger group of randomly sampled U.S. waterpipe tobacco smokers will be valuable in understanding this behavior and developing effective strategies to prevent it.

Development and validation of a quantitative snack and beverage food frequency questionnaire for adolescents.

PubMed

De Cock, N; Van Camp, J; Kolsteren, P; Lachat, C; Huybregts, L; Maes, L; Deforche, B; Verstraeten, R; Vangeel, J; Beullens, K; Eggermont, S; Van Lippevelde, W

2017-04-01

A short, reliable and valid tool to measure snack and beverage consumption in adolescents, taking into account the correct definitions, would benefit both epidemiological and intervention research. The present study aimed to develop a short quantitative beverage and snack food frequency questionnaire (FFQ) and to assess the reliability and validity of this FFQ against three 24-h recalls. Reliability was assessed by comparing estimates of the FFQ administered 14 days apart (FFQ1 and FFQ2) in a convenience sample of 179 adolescents [60.3% male; mean (SD) 14.7 (0.9) years]. Validity was assessed by comparing FFQ1 with three telephone-administered 24-h recalls in a convenience sample of 99 adolescents [52.5% male, mean (SD) 14.8 (0.9) years]. Reliability and validity were assessed using Bland-Altman plots, classification agreements and correlation coefficients for the amount and frequency of consumption of unhealthy snacks, healthy snacks, unhealthy beverages, healthy beverages, and for the healthy snack and beverage ratios. Small mean differences (FFQ1 versus FFQ2) were observed for reliability, ranking ability ranged from fair to substantial, and Spearman coefficients fell within normal ranges. For the validity, mean differences (FFQ1 versus recalls) were small for beverage intake but large for snack intake, except for the healthy snack ratio. Ranking ability ranged from slightly to moderate, and Spearman coefficients fell within normal ranges. Reliability and validity of the FFQ for all outcomes were found to be acceptable at a group level for epidemiological purposes, whereas for intervention purposes only the healthy snack and beverage ratios were found to be acceptable at a group level. © 2016 The British Dietetic Association Ltd.

Temperament, insecure attachment, impulsivity, and sexuality in women in jail.

PubMed

Iliceto, Paolo; Pompili, Maurizio; Candilera, Gabriella; Rosafio, Iole; Erbuto, Denise; Battuello, Michele; Lester, David; Girardi, Paolo

2012-03-01

Women constitute only a small proportion of inmates, but several studies have shown that they have higher rates of psychiatric disturbance than incarcerated men and community samples. Mental health treatment is necessary to prevent severe illness and suicide in these women. The convenience sample consisted of 40 female detainees and 40 controls who were administered self-report questionnaires to assess temperament (TEMPS-A), insecure attachment (ECR), impulsivity (BIS-11), and sexual behavior (SESAMO). The incarcerated women had higher levels of affective temperament (except for hyperthymia), avoidance, anxiety, impulsivity, and psychosexual issues than the female community sample. Many interrelated emotional and affective disturbances affect the physical and psychological well-being of women in jail, and it is possible that these problems may lead to suicide. Health professionals need to develop gender-specific therapeutic interventions for women in jail. © 2012 International Association of Forensic Nurses.

Investigating the role of personal and context-related factors in convenience foods consumption.

PubMed

Contini, Caterina; Boncinelli, Fabio; Gerini, Francesca; Scozzafava, Gabriele; Casini, Leonardo

2018-07-01

In the scenario of food consumptions, we witness the consumer's growing consideration for the "convenience" attribute. Our study intends to understand the consumer behaviour towards convenience-processed foods by analysing in a single model the role of beliefs, personal traits, social influence and market availability. We applied a Structural Equation Model (SEM) to a representative sample of 426 Italian consumers. The results show a correlation between intention to consume convenience-processed foods and social influence, market availability and several personal traits, suggesting strategies for the development of the convenience food market. Copyright © 2018 Elsevier Ltd. All rights reserved.

Convenience food products. Drivers for consumption.

PubMed

Brunner, Thomas A; van der Horst, Klazine; Siegrist, Michael

2010-12-01

Convenience is one of the big trends in the food business. The demand for convenience food products is steadily increasing; therefore, understanding convenience food consumption is an important issue. Despite being vital properties of convenience food, saving time and effort have not been very successful constructs for predicting convenience food consumption. To examine a wide range of possible drivers for convenience food consumption, the present study uses a convenience food frequency questionnaire that asks about consumption behavior. A paper-and-pencil questionnaire was sent out to a representative sample of people in German-speaking Switzerland and yielded N = 918 complete datasets from persons mainly responsible for buying and preparing food in the household. The various convenience food products could be categorized into four groups, which we labeled as highly processed food items, moderately processed food items, single components, and salads. Fifteen drivers were found to have a significant impact either on total convenience consumption or on one of the identified categories. Strong predictors were age, concern about naturalness, nutrition knowledge, and cooking skills. Copyright © 2010 Elsevier Ltd. All rights reserved.

Two means of sampling sexual minority women: how different are the samples of women?

PubMed

Boehmer, Ulrike; Clark, Melissa; Timm, Alison; Ozonoff, Al

2008-01-01

We compared 2 sampling approaches of sexual minority women in 1 limited geographic area to better understand the implications of these 2 sampling approaches. Sexual minority women identified through the Census did not differ on average age or the prevalence of raising children from those sampled using nonrandomized methods. Women in the convenience sample were better educated and lived in smaller households. Modeling the likelihood of disability in this population resulted in contradictory parameter estimates by sampling approach. The degree of variation observed both between sampling approaches and between different parameters suggests that the total population of sexual minority women is still unmeasured. Thoroughly constructed convenience samples will continue to be a useful sampling strategy to further research on this population.

Convenience polyandry or convenience polygyny? Costly sex under female control in a promiscuous primate.

PubMed

Huchard, Elise; Canale, Cindy I; Le Gros, Chloé; Perret, Martine; Henry, Pierre-Yves; Kappeler, Peter M

2012-04-07

Classic sex roles depict females as choosy, but polyandry is widespread. Empirical attempts to understand the evolution of polyandry have often focused on its adaptive value to females, whereas 'convenience polyandry' might simply decrease the costs of sexual harassment. We tested whether constraint-free female strategies favour promiscuity over mating selectivity through an original experimental design. We investigated variation in mating behaviour in response to a reversible alteration of sexual dimorphism in body mass in the grey mouse lemur, a small primate where female brief sexual receptivity allows quantifying polyandry. We manipulated body condition in captive females, predicting that convenience polyandry would increase when females are weaker than males, thus less likely to resist their solicitations. Our results rather support the alternative hypothesis of 'adaptive polyandry': females in better condition are more polyandrous. Furthermore, we reveal that multiple mating incurs significant energetic costs, which are strikingly symmetrical between the sexes. Our study shows that mouse lemur females exert tight control over mating and actively seek multiple mates. The benefits of remating are nevertheless not offset by its costs in low-condition females, suggesting that polyandry is a flexible strategy yielding moderate fitness benefits in this small mammal.

Convenience polyandry or convenience polygyny? Costly sex under female control in a promiscuous primate

PubMed Central

Huchard, Elise; Canale, Cindy I.; Le Gros, Chloé; Perret, Martine; Henry, Pierre-Yves; Kappeler, Peter M.

2012-01-01

Classic sex roles depict females as choosy, but polyandry is widespread. Empirical attempts to understand the evolution of polyandry have often focused on its adaptive value to females, whereas ‘convenience polyandry’ might simply decrease the costs of sexual harassment. We tested whether constraint-free female strategies favour promiscuity over mating selectivity through an original experimental design. We investigated variation in mating behaviour in response to a reversible alteration of sexual dimorphism in body mass in the grey mouse lemur, a small primate where female brief sexual receptivity allows quantifying polyandry. We manipulated body condition in captive females, predicting that convenience polyandry would increase when females are weaker than males, thus less likely to resist their solicitations. Our results rather support the alternative hypothesis of ‘adaptive polyandry’: females in better condition are more polyandrous. Furthermore, we reveal that multiple mating incurs significant energetic costs, which are strikingly symmetrical between the sexes. Our study shows that mouse lemur females exert tight control over mating and actively seek multiple mates. The benefits of remating are nevertheless not offset by its costs in low-condition females, suggesting that polyandry is a flexible strategy yielding moderate fitness benefits in this small mammal. PMID:21976684

Moral decision making in neonatal intensive care.

PubMed

Chally, P S

1992-01-01

To gain information about the perspective that neonatal intensive-care unit nurses use to make moral decisions. Descriptive. Neonatal intensive-care unit of a large teaching hospital in the midwestern United States. Convenience sample of 26 female nurses working in a neonatal intensive-care unit. Audiotaped, semistructured interviews and demographic questionnaires. The results indicated that most (65%) of the nurses used the care perspective to make moral decisions. A small number (12%) used the justice perspective, and the remaining nurses (23%) used a combined care and justice perspective. Both the care and justice perspectives were found to be important for understanding how nurses make moral decisions.

Microbial quality of soft drinks served by the dispensing machines in fast food restaurants and convenience stores in Griffin, Georgia, and surrounding areas.

PubMed

Park, Yoen Ju; Chen, Jinru

2009-12-01

This study was undertaken to evaluate the microbial quality of the soft drinks served by fast food restaurants and gas station convenience stores in Griffin, GA, and surrounding areas. The soft drinks were collected from the dispensing machines in 8 fast food restaurants or gas station convenience stores in 2005 (n = 25) and in 10 fast food restaurants or gas station convenience stores in 2006 (n = 43) and 2007 (n = 43). One hundred milliliters of each soft drink was filtered through a hydrophobic grid membrane filter. The remaining portion of the soft drink was kept at room temperature for 4 h before sampling in order to mimic the possible holding time between purchase and consumption. The membrane filters were sampled for total aerobic bacteria, Enterobacteriaceae, lactic acid bacteria, and yeasts and molds. The microbial counts in the 2006 samples were numerically higher than the counts in the 2007 samples except for the average lactic acid bacteria counts, and were either significantly or numerically higher than the counts in the 2005 samples. Soft drinks sampled after the 4-h holding period had relatively higher counts than those sampled initially, with a few exceptions. Some soft drinks had over 4 log CFU/100 ml of total aerobic bacteria, Enterobacteriaceae, lactic acid bacteria, and yeast and mold cells. The study revealed the microbial quality of soft drinks served by dispensing machines in Griffin, GA, and surrounding areas, emphasizing the importance of effective sanitizing practice in retail settings.

The 'number needed to sample' in primary care research. Comparison of two primary care sampling frames for chronic back pain.

PubMed

Smith, Blair H; Hannaford, Philip C; Elliott, Alison M; Smith, W Cairns; Chambers, W Alastair

2005-04-01

Sampling for primary care research must strike a balance between efficiency and external validity. For most conditions, even a large population sample will yield a small number of cases, yet other sampling techniques risk problems with extrapolation of findings. To compare the efficiency and external validity of two sampling methods for both an intervention study and epidemiological research in primary care--a convenience sample and a general population sample--comparing the response and follow-up rates, the demographic and clinical characteristics of each sample, and calculating the 'number needed to sample' (NNS) for a hypothetical randomized controlled trial. In 1996, we selected two random samples of adults from 29 general practices in Grampian, for an epidemiological study of chronic pain. One sample of 4175 was identified by an electronic questionnaire that listed patients receiving regular analgesic prescriptions--the 'repeat prescription sample'. The other sample of 5036 was identified from all patients on practice lists--the 'general population sample'. Questionnaires, including demographic, pain and general health measures, were sent to all. A similar follow-up questionnaire was sent in 2000 to all those agreeing to participate in further research. We identified a potential group of subjects for a hypothetical trial in primary care based on a recently published trial (those aged 25-64, with severe chronic back pain, willing to participate in further research). The repeat prescription sample produced better response rates than the general sample overall (86% compared with 82%, P < 0.001), from both genders and from the oldest and youngest age groups. The NNS using convenience sampling was 10 for each member of the final potential trial sample, compared with 55 using general population sampling. There were important differences between the samples in age, marital and employment status, social class and educational level. However, among the potential trial sample, there were no demographic differences. Those from the repeat prescription sample had poorer indices than the general population sample in all pain and health measures. The repeat prescription sampling method was approximately five times more efficient than the general population method. However demographic and clinical differences in the repeat prescription sample might hamper extrapolation of findings to the general population, particularly in an epidemiological study, and demonstrate that simple comparison with age and gender of the target population is insufficient.

A machine for haemodialysing very small infants.

PubMed

Everdell, Nicholas L; Coulthard, Malcolm G; Crosier, Jean; Keir, Michael J

2005-05-01

Babies weighing under 6 kg are difficult to dialyse, especially those as small as 1 kg. Peritoneal dialysis is easier than haemodialysis, but is not always possible, and clears molecules less efficiently. Two factors complicate haemodialysis. First, extracorporeal circuits are large relative to a baby's blood volume, necessitating priming with fresh or modified blood. Second, blood flow from infants' access vessels is disproportionately low (Poiseuille's law), causing inadequate dialysis, or clotting within the circuit. These problems are minimised by using single lumen access, a very small circuit, and a reservoir syringe to separate the sampling and dialyser blood flow rates. Its manual operation is tedious, so we developed a computer-controlled, pressure-monitored machine to run it, including adjusting the blood withdrawal rate from poorly sampling lines. We have dialysed four babies weighing 0.8-3.4 kg, with renal failure or metabolic disorders. The circuits did not require priming. Clearances of creatinine, urea, potassium, phosphate and ammonia were mean (SD) 0.54 (0.22) ml/min using one dialyser, and 0.98 (0.22) ml/min using two in parallel. Ammonia clearance in a 2.4 kg baby had a 9 h half-life. Ultrafiltration up to 45 ml/h was achieved easily. This device provided infants with immediate, effective and convenient haemodialysis, typically delivered for prolonged periods.

What do patients need to know? A study to assess patients' satisfaction with information about medicines.

PubMed

Twigg, Michael J; Bhattacharya, Debi; Clark, Allan; Patel, Rina; Rogers, Hannah; Whiteside, Hattie; Yaqoob, Mahavish; Wright, David J

2016-08-01

This study aimed to determine the information needs and reported adherence of patients prescribed medicines for chronic conditions in those who have received a community pharmacy advanced service and those who have not. A questionnaire was constructed using validated tools to measure medication information satisfaction and adherence together with questions eliciting information regarding the use of pharmacy services and demographic characteristics. This questionnaire was distributed from four community pharmacies to a convenience sample of 400 patients as they collected their medicines. Patients were eligible if prescribed more than one regular medicine and attending the pharmacy for longer than 3 months. The questionnaire was returned directly to the university. Two hundred and thirty-two (58%) questionnaires were returned. All respondents desired further information about their prescribed medicines, particularly about potential medication problems. Dissatisfaction centred on side effects, interactions and certain medicine characteristics such as how long it will take to act. Satisfaction with information about medicines and adherence were significantly greater in a subgroup reporting that they had received an advanced pharmacy service, e.g. medicine use review (MUR). Patients who had received an advanced service reported greater adherence and satisfaction with medicine-related information. This was a small, observational study, using a convenience sample of four pharmacies; in order to draw definitive conclusions, a larger study with participants randomised to receive an advanced service is required. © 2016 Royal Pharmaceutical Society.

The convenience food market in Great Britain: convenience food lifestyle (CFL) segments.

PubMed

Buckley, Marie; Cowan, Cathal; McCarthy, Mary

2007-11-01

Convenience foods enable the consumer to save time and effort in food activities, related to shopping, meal preparation and cooking, consumption and post-meal activities. The objective of this paper is to report on the attitudes and reported behaviour of food consumers in Great Britain based on a review of their convenience food lifestyle (CFLs). The paper also reports the development and application of a segmentation technique that can supply information on consumer attitudes towards convenience foods. The convenience food market in Great Britain is examined and the key drivers of growth in this market are highlighted. A survey was applied to a nationally representative sample of 1000 consumers (defined as the persons primarily responsible for food shopping and cooking in the household) in Great Britain in 2002. Segmentation analysis, based on the identification of 20 convenience lifestyle factors, identified four CFL segments of consumers: the 'food connoisseurs' (26%), the 'home meal preparers' (25%), the 'kitchen evaders' (16%) and the 'convenience-seeking grazers' (33%). In particular, the 'kitchen evaders' and the 'convenience-seeking grazers' are identified as convenience-seeking segments. Implications for food producers, in particular, convenience food manufacturers are discussed. The study provides an understanding of the lifestyles of food consumers in Great Britain, and provides food manufacturers with an insight into what motivates individuals to purchase convenience foods.

Para I Famagu'on-Ta: Fruit and Vegetable Intake, Food Store Environment, and Childhood Overweight/Obesity in the Children's Healthy Living Program on Guam

PubMed Central

Matanane, Lenora; Silva, Joshua; Li, Fenfang; Nigg, Claudio; Leon Guerrero, Rachael T; Novotny, Rachel

2017-01-01

This cross-sectional study examined the: (1) association between food store environment (FSE), fruit and vegetable (FV) availability and access, and prevalence of early childhood overweight/obesity (COWOB); and (2) influence of young child actual FV intake on the relationship between the FSE and early COWOB prevalence. Anthropometric and socio-demographic data of children (2 to 8 years; N=466) in baseline communities on Guam participating in the Children's Healthy Living (CHL) Program community trial were included. CDC year 2000 growth charts were used to calculate BMI z-scores and categories. FSE factors (fresh FV scores, store type) were assessed using the CX3 Food Availability and Marketing Survey amended for CHL. ArcGIS maps were constructed with geographic coordinates of participant residences and food stores to calculate food store scores within 1 mile of participant's residences. A sub-sample of participants (n = 355) had Food and Activity Log data to calculate FV and energy intakes. Bivariate correlations and logistic regression evaluated associations. Of 111 stores surveyed, 73% were small markets, 16% were convenience stores, and 11% were large grocery/supermarkets. Supermarkets/large grocery stores averaged the highest FV scores. Most participants did not meet FV intake recommendations while nearly half exceeded energy intake recommendations. Living near a small market was negatively correlated with BMI z-score (r = - 0.129, P < .05) while living near a convenience store was positively correlated with BMI z-score (r = 0.092, P < .05). Logistic regression analysis yielded non-significant associations. The high density of small markets may be an opportunity for FSE intervention but further investigation of Guam's FSE influence on health is needed. PMID:28808612

Para I Famagu'on-Ta: Fruit and Vegetable Intake, Food Store Environment, and Childhood Overweight/Obesity in the Children's Healthy Living Program on Guam.

PubMed

Matanane, Lenora; Fialkowski, Marie Kainoa; Silva, Joshua; Li, Fenfang; Nigg, Claudio; Leon Guerrero, Rachael T; Novotny, Rachel

2017-08-01

This cross-sectional study examined the: (1) association between food store environment (FSE), fruit and vegetable (FV) availability and access, and prevalence of early childhood overweight/obesity (COWOB); and (2) influence of young child actual FV intake on the relationship between the FSE and early COWOB prevalence. Anthropometric and socio-demographic data of children (2 to 8 years; N=466) in baseline communities on Guam participating in the Children's Healthy Living (CHL) Program community trial were included. CDC year 2000 growth charts were used to calculate BMI z-scores and categories. FSE factors (fresh FV scores, store type) were assessed using the CX3 Food Availability and Marketing Survey amended for CHL. ArcGIS maps were constructed with geographic coordinates of participant residences and food stores to calculate food store scores within 1 mile of participant's residences. A sub-sample of participants (n = 355) had Food and Activity Log data to calculate FV and energy intakes. Bivariate correlations and logistic regression evaluated associations. Of 111 stores surveyed, 73% were small markets, 16% were convenience stores, and 11% were large grocery/supermarkets. Supermarkets/large grocery stores averaged the highest FV scores. Most participants did not meet FV intake recommendations while nearly half exceeded energy intake recommendations. Living near a small market was negatively correlated with BMI z-score (r = - 0.129, P < .05) while living near a convenience store was positively correlated with BMI z-score (r = 0.092, P < .05). Logistic regression analysis yielded non-significant associations. The high density of small markets may be an opportunity for FSE intervention but further investigation of Guam's FSE influence on health is needed.

The economic impact of state cigarette taxes and smoke-free air policies on convenience stores.

PubMed

Huang, Jidong; Chaloupka, Frank J

2013-03-01

To investigate whether increasing state cigarette taxes and/or enacting stronger smoke-free air (SFA) policies have negative impact on convenience store density in a state, a proxy that is determined by store openings and closings, which reflects store profits. State-level business count estimates for convenience stores for 50 states and District of Columbia from 1997 to 2009 were analysed using two-way fixed effects regression techniques that control for state-specific and year-specific determinants of convenience store density. The impact of tax and SFA policies was examined using a quasi-experimental research design that exploits changes in cigarette taxes and SFA policies within a state over time. Taxes are found to be uncorrelated with the density of combined convenience stores and gas stations in a state. Taxes are positively correlated with the density of convenience stores; however, the magnitude of this correlation is small, with a 10% increase in state cigarette taxes associated with a 0.19% (p<0.05) increase in the number of convenience stores per million people in a state. State-level SFA policies do not correlate with convenience store density in a state, regardless whether gas stations were included. These results are robust across different model specifications. In addition, they are robust with regard to the inclusion/exclusion of other state-level tobacco control measures and gasoline prices. Contrary to tobacco industry and related organisations' claims, higher cigarette taxes and stronger SFA policies do not negatively affect convenience stores.

Consumers' convenience orientation towards meal preparation: conceptualization and measurement.

PubMed

Candel, M

2001-02-01

Consumer researchers consider convenience orientation towards meal preparation to be a relevant construct for understanding consumer behavior towards foods. This study set out to conceptualize this construct and to develop a scale that measures it. As examined in two different samples of meal preparers, the resulting scale is reliable, satisfies a unifactorial structure and has satisfactory convergent validity. The scale's nomological validity is supported in that it conforms to expectations regarding various psychographic constructs and various food-related behaviors. Convenience orientation was found to be negatively related to cooking enjoyment, involvement with food products and variety seeking, and to be positively related to role overload. The analyses also suggest that the lack of relation between the meal preparer's working status and convenience food consumption, as found in many studies, is due to convenience food not offering enough preparation convenience. Consuming take-away meals and eating in restaurants appear to satisfy the consumer's need for convenience more adequately. Copyright 2001 Academic Press.

Physical, mental, and cognitive function in a convenience sample of centenarians in Australia.

PubMed

Richmond, Robyn L; Law, Jenaleen; Kay-Lambkin, Frances

2011-06-01

To examine the physical, mental, and cognitive function of centenarians. Descriptive study using a structured questionnaire and convenience sampling. Residential care facilities and private dwellings in Australia. A convenience sample of 188 centenarians. The Hospital Anxiety and Depression Scale (HADS) screened for anxiety and depression. The Katz Index of Independence in Activities of Daily Living (Katz ADL) was used to assess functional status. The Quality of Life Scale was used to assess quality of life. The Mini-Mental State Examination (MMSE) was used to screen for dementia. Structured responses were obtained for living arrangement, marital status, social relationships, and supports. Centenarians had regular contact with friends (59%), neighbors (62%), and families (72%); 54% were religious and 43.5% had received social supports. Average MMSE and Katz ADL scores were 21.5 and 3.7, respectively; 45% had scores on the MMSE indicative of dementia, 10% indicated anxiety and 14% depression on the HADS. Participants with poor ratings of health experienced higher rates of anxiety and depression than their healthier counterparts. In this convenience sample of Australian centenarians, anxiety and depression was relatively nonexistent, and most reported a high quality of life. This was despite objective deterioration in functional status, paralleling the aging process, and high dependence on others for everyday tasks. Potentially, this is suggestive of a unique ability within the sample to adapt to aging and its limitations. © 2011, Copyright the Authors. Journal compilation © 2011, The American Geriatrics Society.

Comparative exploration of hydrogen sulfide and water transmembrane free energy surfaces via orthogonal space tempering free energy sampling

DOE PAGES

Lv, Chao; Aitchison, Erick W.; Wu, Dongsheng; ...

2015-06-29

Hydrogen sulfide (H 2S), a commonly known toxic gas compound, possesses unique chemical features that allow this small solute molecule to quickly diffuse through cell membranes. Taking advantage of the recent orthogonal space tempering (OST) method, we comparatively mapped the transmembrane free energy landscapes of H 2S and its structural analogue, water (H 2O), seeking to decipher the molecular determinants that govern their drastically different permeabilities. Here, as revealed by our OST sampling results, in contrast to the highly polar water solute, hydrogen sulfide is evidently amphipathic, and thus inside membrane is favorably localized at the interfacial region, that is,more » the interface between the polar head-group and nonpolar acyl chain regions. Because the membrane binding affinity of H 2S is mainly governed by its small hydrophobic moiety and the barrier height inbetween the interfacial region and the membrane center is largely determined by its moderate polarity, the transmembrane free energy barriers to encounter by this toxic molecule are very small. Moreover when H2S diffuses from the bulk solution to the membrane center, the above two effects nearly cancel each other, so as to lead to a negligible free energy difference. Lastly, this study not only explains why H 2S can quickly pass through cell membranes but also provides a practical illustration on how to use the OST free energy sampling method to conveniently analyze complex molecular processes.« less

Comparative exploration of hydrogen sulfide and water transmembrane free energy surfaces via orthogonal space tempering free energy sampling.

PubMed

Lv, Chao; Aitchison, Erick W; Wu, Dongsheng; Zheng, Lianqing; Cheng, Xiaolin; Yang, Wei

2016-03-05

Hydrogen sulfide (H2 S), a commonly known toxic gas compound, possesses unique chemical features that allow this small solute molecule to quickly diffuse through cell membranes. Taking advantage of the recent orthogonal space tempering (OST) method, we comparatively mapped the transmembrane free energy landscapes of H2 S and its structural analogue, water (H2 O), seeking to decipher the molecular determinants that govern their drastically different permeabilities. As revealed by our OST sampling results, in contrast to the highly polar water solute, hydrogen sulfide is evidently amphipathic, and thus inside membrane is favorably localized at the interfacial region, that is, the interface between the polar head-group and nonpolar acyl chain regions. Because the membrane binding affinity of H2 S is mainly governed by its small hydrophobic moiety and the barrier height inbetween the interfacial region and the membrane center is largely determined by its moderate polarity, the transmembrane free energy barriers to encounter by this toxic molecule are very small. Moreover when H2 S diffuses from the bulk solution to the membrane center, the above two effects nearly cancel each other, so as to lead to a negligible free energy difference. This study not only explains why H2 S can quickly pass through cell membranes but also provides a practical illustration on how to use the OST free energy sampling method to conveniently analyze complex molecular processes. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

A Low Cost Rokkaku Kite Setup for Aerial Photogrammetric System

NASA Astrophysics Data System (ADS)

Khan, A. F.; Khurshid, K.; Saleh, N.; Yousuf, A. A.

2015-03-01

Orthogonally Projected Area (OPA) of a geographical feature has primarily been studied utilizing rather time consuming field based sampling techniques. Remote sensing on the contrary provides the ability to acquire large scale data at a snapshot of time and lets the OPA to be calculated conveniently and with reasonable accuracy. Unfortunately satellite based remote sensing provides data at high cost and limited spatial resolution for scientific studies focused at small areas such as micro lakes micro ecosystems, etc. More importantly, recent satellite data may not be readily available for a particular location. This paper describes a low cost photogrammetric system to measure the OPA of a small scale geographic feature such as a plot of land, micro lake or an archaeological site, etc. Fitted with a consumer grade digital imaging system, a Rokkaku kite aerial platform with stable flight characteristics is designed and fabricated for image acquisition. The data processing procedure involves automatic Ground Control Point (GCP) detection, intelligent target area shape determination with minimal human input. A Graphical User Interface (GUI) is built from scratch in MATLAB to allow the user to conveniently process the acquired data, archive and retrieve the results. Extensive on-field experimentation consists of multiple geographic features including flat land surfaces, buildings, undulating rural areas, and an irregular shaped micro lake, etc. Our results show that the proposed system is not only low cost, but provides a framework that is easy and fast to setup while maintaining the required constraints on the accuracy.

14 CFR 206.5 - Small aircraft operations by certificated carriers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Small aircraft operations by certificated carriers. 206.5 Section 206.5 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CERTIFICATES OF PUBLIC CONVENIENCE AND NECESSITY: SPECIAL...

Is the food environment surrounding schools associated with the diet quality of adolescents in Otago, New Zealand?

PubMed

Clark, Emma M; Quigg, Robin; Wong, Jyh Eiin; Richards, Rose; Black, Katherine E; Skidmore, Paula M L

2014-11-01

Using a sample of adolescents from schools in Otago, New Zealand, associations between food outlets around schools and dietary quality were investigated. Food outlet environment data were derived using GIS data. Multivariate regression analysis results showed that outlet density, in an 800m buffer around schools, of cafes and restaurants, supermarkets and takeaways was associated with higher Diet Quality Index scores in boys, and distance to nearest outlet for convenience stores, cafes and restaurants and supermarkets with lower scores for girls. Effect sizes were small, suggesting that the food environment around schools plays a minor role in adolescent diet quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

A comparison of the comfort and convenience of automatic safety belt systems among selected 1988-1989 model year automobiles

DOT National Transportation Integrated Search

1989-06-01

Author's abstract: A nonrandom sample of 120 disproportionately short, tall, and overweight drivers compared the comfort and convenience of the automatic safety belt systems used in seventeen automobiles. Nine vehicles had motorized shoulder belts wi...

Guidelines for Measuring Disease Episodes: An Analysis of the Effects on the Components of Expenditure Growth.

PubMed

Dunn, Abe; Liebman, Eli; Rittmueller, Lindsey; Shapiro, Adam Hale

2017-04-01

To provide guidelines to researchers measuring health expenditures by disease and compare these methodologies' implied inflation estimates. A convenience sample of commercially insured individuals over the 2003 to 2007 period from Truven Health. Population weights are applied, based on age, sex, and region, to make the sample of over 4 million enrollees representative of the entire commercially insured population. Different methods are used to allocate medical-care expenditures to distinct condition categories. We compare the estimates of disease-price inflation by method. Across a variety of methods, the compound annual growth rate stays within the range 3.1 to 3.9 percentage points. Disease-specific inflation measures are more sensitive to the selected methodology. The selected allocation method impacts aggregate inflation rates, but considering the variety of methods applied, the differences appear small. Future research is necessary to better understand these differences in other population samples and to connect disease expenditures to measures of quality. © Health Research and Educational Trust.

Evaluation of Respondent-Driven Sampling

PubMed Central

McCreesh, Nicky; Frost, Simon; Seeley, Janet; Katongole, Joseph; Tarsh, Matilda Ndagire; Ndunguse, Richard; Jichi, Fatima; Lunel, Natasha L; Maher, Dermot; Johnston, Lisa G; Sonnenberg, Pam; Copas, Andrew J; Hayes, Richard J; White, Richard G

2012-01-01

Background Respondent-driven sampling is a novel variant of link-tracing sampling for estimating the characteristics of hard-to-reach groups, such as HIV prevalence in sex-workers. Despite its use by leading health organizations, the performance of this method in realistic situations is still largely unknown. We evaluated respondent-driven sampling by comparing estimates from a respondent-driven sampling survey with total-population data. Methods Total-population data on age, tribe, religion, socioeconomic status, sexual activity and HIV status were available on a population of 2402 male household-heads from an open cohort in rural Uganda. A respondent-driven sampling (RDS) survey was carried out in this population, employing current methods of sampling (RDS sample) and statistical inference (RDS estimates). Analyses were carried out for the full RDS sample and then repeated for the first 250 recruits (small sample). Results We recruited 927 household-heads. Full and small RDS samples were largely representative of the total population, but both samples under-represented men who were younger, of higher socioeconomic status, and with unknown sexual activity and HIV status. Respondent-driven-sampling statistical-inference methods failed to reduce these biases. Only 31%-37% (depending on method and sample size) of RDS estimates were closer to the true population proportions than the RDS sample proportions. Only 50%-74% of respondent-driven-sampling bootstrap 95% confidence intervals included the population proportion. Conclusions Respondent-driven sampling produced a generally representative sample of this well-connected non-hidden population. However, current respondent-driven-sampling inference methods failed to reduce bias when it occurred. Whether the data required to remove bias and measure precision can be collected in a respondent-driven sampling survey is unresolved. Respondent-driven sampling should be regarded as a (potentially superior) form of convenience-sampling method, and caution is required when interpreting findings based on the sampling method. PMID:22157309

Internet Gaming Disorder Explains Unique Variance in Psychological Distress and Disability After Controlling for Comorbid Depression, OCD, ADHD, and Anxiety.

PubMed

Pearcy, Benjamin T D; McEvoy, Peter M; Roberts, Lynne D

2017-02-01

This study extends knowledge about the relationship of Internet Gaming Disorder (IGD) to other established mental disorders by exploring comorbidities with anxiety, depression, Attention Deficit Hyperactivity Disorder (ADHD), and obsessive compulsive disorder (OCD), and assessing whether IGD accounts for unique variance in distress and disability. An online survey was completed by a convenience sample that engages in Internet gaming (N = 404). Participants meeting criteria for IGD based on the Personal Internet Gaming Disorder Evaluation-9 (PIE-9) reported higher comorbidity with depression, OCD, ADHD, and anxiety compared with those who did not meet the IGD criteria. IGD explained a small proportion of unique variance in distress (1%) and disability (3%). IGD accounted for a larger proportion of unique variance in disability than anxiety and ADHD, and a similar proportion to depression. Replications with clinical samples using longitudinal designs and structured diagnostic interviews are required.

Sampling designs for HIV molecular epidemiology with application to Honduras.

PubMed

Shepherd, Bryan E; Rossini, Anthony J; Soto, Ramon Jeremias; De Rivera, Ivette Lorenzana; Mullins, James I

2005-11-01

Proper sampling is essential to characterize the molecular epidemiology of human immunodeficiency virus (HIV). HIV sampling frames are difficult to identify, so most studies use convenience samples. We discuss statistically valid and feasible sampling techniques that overcome some of the potential for bias due to convenience sampling and ensure better representation of the study population. We employ a sampling design called stratified cluster sampling. This first divides the population into geographical and/or social strata. Within each stratum, a population of clusters is chosen from groups, locations, or facilities where HIV-positive individuals might be found. Some clusters are randomly selected within strata and individuals are randomly selected within clusters. Variation and cost help determine the number of clusters and the number of individuals within clusters that are to be sampled. We illustrate the approach through a study designed to survey the heterogeneity of subtype B strains in Honduras.

Evolution and Protein Packaging of Small Molecule RNA Aptamers

PubMed Central

Lau, Jolene L.; Baksh, Michael M.; Fiedler, Jason D.; Brown, Steven D.; Kussrow, Amanda; Bornhop, Darryl J.; Ordoukhanian, Phillip

2011-01-01

A high-affinity RNA aptamer (Kd = 50 nM) was efficiently identified by SELEX against a heteroaryl dihydropyrimidine structure, chosen as a representative drug-like molecule with no cross reactivity with mammalian or bacterial cells. This aptamer, its weaker-binding variants, and a known aptamer against theophylline were each embedded in a longer RNA sequence that was encapsidated inside a virus-like particle by a convenient expression technique. These nucleoprotein particles were shown by backscattering interferometry to bind to the small-molecule ligands with affinities similar to those of the free (non-encapsidated) aptamers. The system therefore comprises a general approach to the production and sequestration of functional RNA molecules, characterized by a convenient label-free analytical technique. PMID:21899290

Determination of Minimum Training Sample Size for Microarray-Based Cancer Outcome Prediction–An Empirical Assessment

PubMed Central

Cheng, Ningtao; Wu, Leihong; Cheng, Yiyu

2013-01-01

The promise of microarray technology in providing prediction classifiers for cancer outcome estimation has been confirmed by a number of demonstrable successes. However, the reliability of prediction results relies heavily on the accuracy of statistical parameters involved in classifiers. It cannot be reliably estimated with only a small number of training samples. Therefore, it is of vital importance to determine the minimum number of training samples and to ensure the clinical value of microarrays in cancer outcome prediction. We evaluated the impact of training sample size on model performance extensively based on 3 large-scale cancer microarray datasets provided by the second phase of MicroArray Quality Control project (MAQC-II). An SSNR-based (scale of signal-to-noise ratio) protocol was proposed in this study for minimum training sample size determination. External validation results based on another 3 cancer datasets confirmed that the SSNR-based approach could not only determine the minimum number of training samples efficiently, but also provide a valuable strategy for estimating the underlying performance of classifiers in advance. Once translated into clinical routine applications, the SSNR-based protocol would provide great convenience in microarray-based cancer outcome prediction in improving classifier reliability. PMID:23861920

The impact of cultural diversity forum on students' openness to diversity.

PubMed

Sanner, Susan; Baldwin, Dee; Cannella, Kathleen A S; Charles, Jennell; Parker, Lillian

2010-01-01

As the population demographics for the United States (U.S.) shift towards increasing diversity, it is essential that nurses provide culturally competent care. Cultural sensitivity has been identified as a major curricular element in the American Association of Colleges of Nursing's (AACN) The Essentials of Baccalaureate Education for Professional Nursing Practice. Thus it is imperative that nursing faculty use effective strategies to help nursing students develop cultural sensitivity and competence. Educational workshops focusing on cultural diversity are usually designed to increase people's cultural sensitivity. The purpose of this study was to assess the effectiveness of a cultural diversity forum on nursing students' cultural sensitivity as measured by their openness to diversity. A convenience sample of students was recruited from a public university in the southeastern United States. The workshop was designed as a forum that combined a keynote presentation, shared meal, and a small group interactional activity. Cultural sensitivity was measured using the Openness to Diversity/Challenge Scale (ODCS), and was administered to students before and after the forum. A convenience sample of 47 students agreed to participate and completed both the pretest and posttest. Following the workshop, the students had more cultural sensitivity as measured by their scores on the ODCS (Wilcoxin Signed-Rank test z= -3.286, p = 0.001). The findings suggested that an educational format like the cultural diversity forum can promote students' cultural sensitivity. Further research needs to continue to focus on the effectiveness of strategies to increase the cultural sensitivity of baccalaureate nursing students.

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

Lv, Chao; Aitchison, Erick W.; Wu, Dongsheng

Hydrogen sulfide (H 2S), a commonly known toxic gas compound, possesses unique chemical features that allow this small solute molecule to quickly diffuse through cell membranes. Taking advantage of the recent orthogonal space tempering (OST) method, we comparatively mapped the transmembrane free energy landscapes of H 2S and its structural analogue, water (H 2O), seeking to decipher the molecular determinants that govern their drastically different permeabilities. Here, as revealed by our OST sampling results, in contrast to the highly polar water solute, hydrogen sulfide is evidently amphipathic, and thus inside membrane is favorably localized at the interfacial region, that is,more » the interface between the polar head-group and nonpolar acyl chain regions. Because the membrane binding affinity of H 2S is mainly governed by its small hydrophobic moiety and the barrier height inbetween the interfacial region and the membrane center is largely determined by its moderate polarity, the transmembrane free energy barriers to encounter by this toxic molecule are very small. Moreover when H2S diffuses from the bulk solution to the membrane center, the above two effects nearly cancel each other, so as to lead to a negligible free energy difference. Lastly, this study not only explains why H 2S can quickly pass through cell membranes but also provides a practical illustration on how to use the OST free energy sampling method to conveniently analyze complex molecular processes.« less

An evaluation of authentication methods for smartphone based on users’ preferences

NASA Astrophysics Data System (ADS)

Sari, P. K.; Ratnasari, G. S.; Prasetio, A.

2016-04-01

This study discusses about smartphone screen lock preferences using some types of authentication methods. The purpose is to determine the user behaviours based on the perceived security and convenience, as well as the preferences for different types of authentication methods. Variables used are the considerations for locking the screens and the types of authentication methods. The population consists of the smartphone users with the total samples of 400 respondents within a nonprobability sampling method. Data analysis method used is the descriptive analysis. The results showed that the convenience factor is still the major consideration for locking the smartphone screens. Majority of the users chose the pattern unlock as the most convenient method to use. Meanwhile, fingerprint unlock becomes the most secure method in the users’ perceptions and as the method chosen to be used in the future.

History of abuse and organic difficulties in a convenience sample of 46 ultra-orthodox males with pedophilia.

PubMed

Witztum, Eliezer; Daie, Netzer; Daie-Gabai, Ayala; Rosler, Ariel

2012-01-01

Evidence has started to accumulate that relates pedophilia to a history of being a victim of sexual abuse as well as to comorbidity with organic vulnerabilities. During a naturalistic study regarding treatment of pedophilia, the authors had access to clinical and psychodiagnostic evaluations of Israeli Jewish ultraorthodox male pedophiles outside the forensic system. Using psychiatric examination as well as a battery of psychological tests, presence of history of trauma as well as comorbidity with organic vulnerabilities among this unique sub-group was examined. This survey was part of a larger scale research on the effectiveness of Decapeptyl injections as treatment for pedophilia. All participants in the original research underwent comprehensive psychological assessment including an extensive clinical interview as well as psychological tests (Bender, Rorschach and TAT). Of the patients participating in the research, this survey focused on the group of 46 ultra-orthodox male pedophiles. Cross-tabs analyses were conducted in order to examine prevalence of history of trauma and organic vulnerabilities in this specific group. Based on self reports combined with corroborating reports (obtained from parents, educators and medical staff), together with indications in psychological tests, we found that 82.6% of participants were victims of sexual trauma as children and 87% suffer from some kind of organic vulnerability (learning disabilities, disinhibitions, etc.). LIMITATIONS of this small convenience sample that influence ability to generalize are discussed. The current survey indicates that in this sample, the ultra-orthodox male pedophile was frequently a victim of childhood sexual trauma, and exhibited indications of organic vulnerabilities. This is more pronounced than findings in previous studies, and calls for further research in order to understand the underlying causes.

Low-energy transmission electron diffraction and imaging of large-area graphene

PubMed Central

Zhao, Wei; Xia, Bingyu; Lin, Li; Xiao, Xiaoyang; Liu, Peng; Lin, Xiaoyang; Peng, Hailin; Zhu, Yuanmin; Yu, Rong; Lei, Peng; Wang, Jiangtao; Zhang, Lina; Xu, Yong; Zhao, Mingwen; Peng, Lianmao; Li, Qunqing; Duan, Wenhui; Liu, Zhongfan; Fan, Shoushan; Jiang, Kaili

2017-01-01

Two-dimensional (2D) materials have attracted interest because of their excellent properties and potential applications. A key step in realizing industrial applications is to synthesize wafer-scale single-crystal samples. Until now, single-crystal samples, such as graphene domains up to the centimeter scale, have been synthesized. However, a new challenge is to efficiently characterize large-area samples. Currently, the crystalline characterization of these samples still relies on selected-area electron diffraction (SAED) or low-energy electron diffraction (LEED), which is more suitable for characterizing very small local regions. This paper presents a highly efficient characterization technique that adopts a low-energy electrostatically focused electron gun and a super-aligned carbon nanotube (SACNT) film sample support. It allows rapid crystalline characterization of large-area graphene through a single photograph of a transmission-diffracted image at a large beam size. Additionally, the low-energy electron beam enables the observation of a unique diffraction pattern of adsorbates on the suspended graphene at room temperature. This work presents a simple and convenient method for characterizing the macroscopic structures of 2D materials, and the instrument we constructed allows the study of the weak interaction with 2D materials. PMID:28879233

Low-energy transmission electron diffraction and imaging of large-area graphene.

PubMed

Zhao, Wei; Xia, Bingyu; Lin, Li; Xiao, Xiaoyang; Liu, Peng; Lin, Xiaoyang; Peng, Hailin; Zhu, Yuanmin; Yu, Rong; Lei, Peng; Wang, Jiangtao; Zhang, Lina; Xu, Yong; Zhao, Mingwen; Peng, Lianmao; Li, Qunqing; Duan, Wenhui; Liu, Zhongfan; Fan, Shoushan; Jiang, Kaili

2017-09-01

Two-dimensional (2D) materials have attracted interest because of their excellent properties and potential applications. A key step in realizing industrial applications is to synthesize wafer-scale single-crystal samples. Until now, single-crystal samples, such as graphene domains up to the centimeter scale, have been synthesized. However, a new challenge is to efficiently characterize large-area samples. Currently, the crystalline characterization of these samples still relies on selected-area electron diffraction (SAED) or low-energy electron diffraction (LEED), which is more suitable for characterizing very small local regions. This paper presents a highly efficient characterization technique that adopts a low-energy electrostatically focused electron gun and a super-aligned carbon nanotube (SACNT) film sample support. It allows rapid crystalline characterization of large-area graphene through a single photograph of a transmission-diffracted image at a large beam size. Additionally, the low-energy electron beam enables the observation of a unique diffraction pattern of adsorbates on the suspended graphene at room temperature. This work presents a simple and convenient method for characterizing the macroscopic structures of 2D materials, and the instrument we constructed allows the study of the weak interaction with 2D materials.

Vortex distribution in small star-shaped Mo80Ge20 plate

NASA Astrophysics Data System (ADS)

Vu, The Dang; Matsumoto, Hitoshi; Miyoshi, Hiroki; Huy, Ho Thanh; Shishido, Hiroaki; Kato, Masaru; Ishida, Takekazu

2017-02-01

We investigated vortex states in small star-shaped Mo80Ge20 plates both theoretically and experimentally. The numerical calculations of the Ginzburg-Landau equation have been carried out with the aid of the finite element method, which is convenient to treat an arbitrarily shaped superconductor. The experimental results were observed by using a scanning SQUID microscope. Through systematic measurements, we figured out how vortices form symmetric configuration with increasing the magnetic field. The vortex distribution tends to adapt to one of five mirror symmetric lines when vortices were located at the five triangular horns of a star-shaped plate. The crystalline homogeneity of a sample was confirmed by the X-ray diffraction and the superconducting properties so that vortices are easily able to move for accommodating vortices in the geometric symmetry of the star-shaped plate. The experimental vortex configurations obtained for a star-shaped plate are in good agreement with theoretical predictions from the nonlinear Ginzburg-Landau equation.

HIGH VOLUME INJECTION FOR GCMS ANALYSIS OF PARTICULATE ORGANIC SPECIES IN AMBIENT AIR

EPA Science Inventory

Detection of organic species in ambient particulate matter typically requires large air sample volumes, frequently achieved by grouping samples into monthly composites. Decreasing the volume of air sample required would allow shorter collection times and more convenient sample c...

Methodology Series Module 5: Sampling Strategies.

PubMed

Setia, Maninder Singh

2016-01-01

Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ' Sampling Method'. There are essentially two types of sampling methods: 1) probability sampling - based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling - based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ' random sample' when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ' generalizability' of these results. In such a scenario, the researcher may want to use ' purposive sampling' for the study.

A simple method for the analysis of particle sizes of forage and total mixed rations.

PubMed

Lammers, B P; Buckmaster, D R; Heinrichs, A J

1996-05-01

A simple separator was developed to determine the particle sizes of forage and TMR that allows for easy separation of wet forage into three fractions and also allows plotting of the particle size distribution. The device was designed to mimic the laboratory-scale separator for forage particle sizes that was specified by Standard S424 of the American Society of Agricultural Engineers. A comparison of results using the standard device and the newly developed separator indicated no difference in ability to predict fractions of particles with maximum length of less than 8 and 19 mm. The separator requires a small quantity of sample (1.4 L) and is manually operated. The materials on the screens and bottom pan were weighed to obtain the cumulative percentage of sample that was undersize for the two fractions. The results were then plotted using the Weibull distribution, which proved to be the best fit for the data. Convenience samples of haycrop silage, corn silage, and TMR from farms in the northeastern US were analyzed using the forage and TMR separator, and the range of observed values are given.

Methodology Series Module 5: Sampling Strategies

PubMed Central

Setia, Maninder Singh

2016-01-01

Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ‘ Sampling Method’. There are essentially two types of sampling methods: 1) probability sampling – based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling – based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ‘ random sample’ when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ‘ generalizability’ of these results. In such a scenario, the researcher may want to use ‘ purposive sampling’ for the study. PMID:27688438

Sampling bias in climate-conflict research

NASA Astrophysics Data System (ADS)

Adams, Courtland; Ide, Tobias; Barnett, Jon; Detges, Adrien

2018-03-01

Critics have argued that the evidence of an association between climate change and conflict is flawed because the research relies on a dependent variable sampling strategy1-4. Similarly, it has been hypothesized that convenience of access biases the sample of cases studied (the `streetlight effect'5). This also gives rise to claims that the climate-conflict literature stigmatizes some places as being more `naturally' violent6-8. Yet there has been no proof of such sampling patterns. Here we test whether climate-conflict research is based on such a biased sample through a systematic review of the literature. We demonstrate that research on climate change and violent conflict suffers from a streetlight effect. Further, studies which focus on a small number of cases in particular are strongly informed by cases where there has been conflict, do not sample on the independent variables (climate impact or risk), and hence tend to find some association between these two variables. These biases mean that research on climate change and conflict primarily focuses on a few accessible regions, overstates the links between both phenomena and cannot explain peaceful outcomes from climate change. This could result in maladaptive responses in those places that are stigmatized as being inherently more prone to climate-induced violence.

A flux extraction device to measure the magnetic moment of large samples; application to bulk superconductors.

PubMed

Egan, R; Philippe, M; Wera, L; Fagnard, J F; Vanderheyden, B; Dennis, A; Shi, Y; Cardwell, D A; Vanderbemden, P

2015-02-01

We report the design and construction of a flux extraction device to measure the DC magnetic moment of large samples (i.e., several cm(3)) at cryogenic temperature. The signal is constructed by integrating the electromotive force generated by two coils wound in series-opposition that move around the sample. We show that an octupole expansion of the magnetic vector potential can be used conveniently to treat near-field effects for this geometrical configuration. The resulting expansion is tested for the case of a large, permanently magnetized, type-II superconducting sample. The dimensions of the sensing coils are determined in such a way that the measurement is influenced by the dipole magnetic moment of the sample and not by moments of higher order, within user-determined upper bounds. The device, which is able to measure magnetic moments in excess of 1 A m(2) (1000 emu), is validated by (i) a direct calibration experiment using a small coil driven by a known current and (ii) by comparison with the results of numerical calculations obtained previously using a flux measurement technique. The sensitivity of the device is demonstrated by the measurement of flux-creep relaxation of the magnetization in a large bulk superconductor sample at liquid nitrogen temperature (77 K).

Outcomes of a community-based HIV-prevention pilot programme for township men who have sex with men in Cape Town, South Africa.

PubMed

Batist, Elizabeth; Brown, Benjamin; Scheibe, Andrew; Baral, Stefan D; Bekker, Linda-Gail

2013-12-02

Men who have sex with men (MSM) in Cape Town's townships remain in need of targeted HIV-prevention services. In 2012, a pilot community-based HIV-prevention programme was implemented that aimed to reach MSM in five Cape Town townships, disseminate HIV-prevention information and supplies, and promote the use of condoms and HIV services. Convenience sampling was used to recruit self-identified MSM who were 18 years old or older in five Cape Town townships. The six-month pilot programme trained five community leaders who, along with staff, provided HIV-prevention information and supplies to MSM through small-group meetings, community-based social activities and inter-community events. After the completion of the pilot programme, in-depth interviews and focus group discussions (FGDs) were conducted with a subset of conveniently sampled participants and with each of the community leaders. Qualitative data were then analyzed thematically. Overall, 98 mostly gay-identified black MSM consented to participate, 57 community-based activities were facilitated and 9 inter-community events were conducted. Following their enrollment, 60% (59/98) of participants attended at least one pilot activity. Of those participants, 47% (28/59) attended at least half of the scheduled activities. A total of 36 participants took part in FGDs, and five in-depth interviews were completed with community leaders. Participants reported gaining access to MSM-specific HIV-prevention information, condoms and water-based lubricant through the small-group meetings. Some participants described how their feelings of loneliness, social isolation, self-esteem and self-efficacy were improved after taking part. The social activities and group meetings were viable strategies for disseminating HIV-prevention information, condoms and water-based lubricant to MSM in this setting. Many MSM were also able to receive social support, reduce social isolation and improve their self-esteem. Further research is needed to explore factors affecting attendance and the sustainability of these activities. Perspectives of MSM who did not attend pilot activities regularly were not equally represented in the final qualitative interviews, which could bias the findings. The use of community-based activities and small-group meetings should be explored further as components to ongoing HIV-prevention interventions for MSM in this setting.

The allele-frequency spectrum in a decoupled Moran model with mutation, drift, and directional selection, assuming small mutation rates.

PubMed

Vogl, Claus; Clemente, Florian

2012-05-01

We analyze a decoupled Moran model with haploid population size N, a biallelic locus under mutation and drift with scaled forward and backward mutation rates θ(1)=μ(1)N and θ(0)=μ(0)N, and directional selection with scaled strength γ=sN. With small scaled mutation rates θ(0) and θ(1), which is appropriate for single nucleotide polymorphism data in highly recombining regions, we derive a simple approximate equilibrium distribution for polymorphic alleles with a constant of proportionality. We also put forth an even simpler model, where all mutations originate from monomorphic states. Using this model we derive the sojourn times, conditional on the ancestral and fixed allele, and under equilibrium the distributions of fixed and polymorphic alleles and fixation rates. Furthermore, we also derive the distribution of small samples in the diffusion limit and provide convenient recurrence relations for calculating this distribution. This enables us to give formulas analogous to the Ewens-Watterson estimator of θ for biased mutation rates and selection. We apply this theory to a polymorphism dataset of fourfold degenerate sites in Drosophila melanogaster. Copyright © 2012 Elsevier Inc. All rights reserved.

A synthesis of convenience survey and other data to estimate undiagnosed HIV infection among men who have sex with men in England and Wales.

PubMed

Walker, Kate; Seaman, Shaun R; De Angelis, Daniela; Presanis, Anne M; Dodds, Julie P; Johnson, Anne M; Mercey, Danielle; Gill, O Noel; Copas, Andrew J

2011-10-01

Hard-to-reach population subgroups are typically investigated using convenience sampling, which may give biased estimates. Combining information from such surveys, a probability survey and clinic surveillance, can potentially minimize the bias. We developed a methodology to estimate the prevalence of undiagnosed HIV infection among men who have sex with men (MSM) in England and Wales aged 16-44 years in 2003, making fuller use of the available data than earlier work. We performed a synthesis of three data sources: genitourinary medicine clinic surveillance (11 380 tests), a venue-based convenience survey including anonymous HIV testing (3702 MSM) and a general population sexual behaviour survey (134 MSM). A logistic regression model to predict undiagnosed infection was fitted to the convenience survey data and then applied to the MSMs in the population survey to estimate the prevalence of undiagnosed infection in the general MSM population. This estimate was corrected for selection biases in the convenience survey using clinic surveillance data. A sensitivity analysis addressed uncertainty in our assumptions. The estimated prevalence of undiagnosed HIV in MSM was 2.4% [95% confidence interval (95% CI 1.7-3.0%)], and between 1.6% (95% CI 1.1-2.0%) and 3.3% (95% CI 2.4-4.1%) depending on assumptions; corresponding to 5500 (3390-7180), 3610 (2180-4740) and 7570 (4790-9840) men, and undiagnosed fractions of 33, 24 and 40%, respectively. Our estimates are consistent with earlier work that did not make full use of data sources. Reconciling data from multiple sources, including probability-, clinic- and venue-based convenience samples can reduce bias in estimates. This methodology could be applied in other settings to take full advantage of multiple imperfect data sources.

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

Hamilton, T.; Jones, H.; Wong, K.

The Marshall Islands Environmental Characterization and Dose Assessment Program has recently implemented waste minimization measures to reduce low level radioactive (LLW) and low level mixed (LLWMIXED) waste streams at the Lawrence Livermore National Laboratory (LLNL). Several thousand environmental samples are collected annually from former US nuclear test sites in the Marshall Islands, and returned to LLNL for processing and radiometric analysis. In the past, we analyzed coconut milk directly by gamma-spectrometry after adding formaldehyde (as preservative) and sealing the fluid in metal cans. This procedure was not only tedious and time consuming but generated storage and waste disposal problems. Wemore » have now reduced the number of coconut milk samples required for analysis from 1500 per year to approximately 250, and developed a new analytical procedure which essentially eliminates the associated mixed radioactive waste stream. Coconut milk samples are mixed with a few grams of ammonium-molydophosphate (AMP) which quantitatively scavenges the target radionuclide cesium 137 in an ion-exchange process. The AMP is then separated from the mixture and sealed in a plastic container. The bulk sample material can be disposed of as a non- radioactive non-hazardous waste, and the relatively small amount of AMP conveniently counted by gamma-spectrometry, packaged and stored for future use.« less

Comparison of femoroacetabular impingement-related radiographic features in a convenience sample of Japanese patients with and without herniation pits.

PubMed

Mineta, Kazuaki; Goto, Tomohiro; Wada, Keizo; Tamaki, Yasuaki; Hamada, Daisuke; Higashino, Kosaku; Sairyo, Koichi

2016-08-01

To examine the prevalence of herniation pits (HPs) and to evaluate differences in radiographic features related to femoroacetabular impingement-a hip disorder with abnormal abutment between the acetabulum and femur-between hips with and without HPs in a convenience sample of Japanese patients. We reviewed 1,178 hips on each side (695 men, 483 women; mean age, 58.2 years) using computed tomographic images. The radiological assessments of hip morphology were performed by measuring the lateral center edge angle, acetabular index, acetabular version, alpha angle, and femoral head-neck offset. HPs were defined as the round or oval cystic lesions surrounded by sclerotic bone located below the anterior femoral neck cortex. Intraclass and interclass reproducibility of all radiographic measurements was acceptable (ICC: 0.71-0.98). The prevalence of HPs was 13.9 % in all subjects and was significantly higher in men (18.1 %) than in women (7.8 %; p < 0.001). HPs were larger in male (p < 0.001) and elderly subjects (p < 0.005). In subjects with HPs, the alpha angle was larger and femoral head-neck offset and offset ratio were smaller in the cohort overall and in men. Logistic regression analysis revealed the association between radiological cam-type FAI and HPs in all subjects (odds ratio: 1.86, p < 0.001). We revealed the prevalence of HPs and showed it has a predilection for men in this Japanese cohort. Femoral head asphericity or small head-neck offset was more common in subjects with HPs than those without HPs.

A highly sensitive and versatile virus titration assay in the 96-well microplate format.

PubMed

Borisevich, V; Nistler, R; Hudman, D; Yamshchikov, G; Seregin, A; Yamshchikov, V

2008-02-01

This report describes a fast, reproducible, inexpensive and convenient assay system for virus titration in the 96-well format. The micromethod substantially increases assay throughput and improves the data reproducibility. A highly simplified variant of virus quantification is based on immunohistochemical detection of virus amplification foci obtained without use of agarose or semisolid overlays. It can be incorporated into several types of routine virological assays successfully replacing the laborious and time-consuming conventional methods based on plaque formation under semisolid overlays. The method does not depend on the development of CPE and can be accommodated to assay viruses with substantial differences in growth properties. The use of enhanced immunohistochemical detection enabled a five- to six-fold reduction of the total assay time. The micromethod was specifically developed to take advantage of multichannel pipettor use to simplify handling of a large number of samples. The method performs well with an inexpensive low-power binocular, thus offering a routine assay system usable outside of specialized laboratory setting, such as for testing of clinical or field samples. When used in focus reduction-neutralization tests (FRNT), the method accommodates very small volumes of immune serum, which is often a decisive factor in experiments involving small rodent models.

Neighborhood food environment role in modifying psychosocial stress-diet relationships.

PubMed

Zenk, Shannon N; Schulz, Amy J; Izumi, Betty T; Mentz, Graciela; Israel, Barbara A; Lockett, Murlisa

2013-06-01

Exposure to highly palatable foods may increase eating in response to stress, but this behavioral response has not been examined in relation to the neighborhood food environment. This study examined whether the neighborhood food environment modified relationships between psychosocial stress and dietary behaviors. Probability-sample survey (n=460) and in-person food environment audit data were used. Dietary behaviors were measured using 17 snack food items and a single eating-out-of-home item. Chronic stress was derived from five subscales; major life events was a count of nine items. The neighborhood food environment was measured as availability of large grocery stores, small grocery stores, and convenience stores, as well as proportion of restaurants that were fast food. Two-level hierarchical regression models were estimated. Snack food intake was positively associated with convenience store availability and negatively associated with large grocery store availability. The measures of chronic stress and major life events were generally not associated with either dietary behavior overall, although Latinos were less likely to eat out at high levels of major life events than African Americans. Stress-neighborhood food environment interactions were not statistically significant. Important questions remain regarding the role of the neighborhood food environment in the stress-diet relationship that warrant further investigation. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Leeb Hardness Test for Rock: An Updated Methodology and UCS Correlation

NASA Astrophysics Data System (ADS)

Corkum, A. G.; Asiri, Y.; El Naggar, H.; Kinakin, D.

2018-03-01

The Leeb hardness test (LHT with test value of L D ) is a rebound hardness test, originally developed for metals, that has been correlated with the Unconfined Compressive Strength (test value of σ c ) of rock by several authors. The tests can be carried out rapidly, conveniently and nondestructively on core and block samples or on rock outcrops. This makes the relatively small LHT device convenient for field tests. The present study compiles test data from literature sources and presents new laboratory testing carried out by the authors to develop a substantially expanded database with wide-ranging rock types. In addition, the number of impacts that should be averaged to comprise a "test result" was revisited along with the issue of test specimen size. Correlation for L D and σ c for various rock types is provided along with recommended testing methodology. The accuracy of correlated σ c estimates was assessed and reasonable correlations were observed between L D and σ c . The study findings show that LHT can be useful particularly for field estimation of σ c and offers a significant improvement over the conventional field estimation methods outlined by the ISRM (e.g., hammer blows). This test is rapid and simple, with relatively low equipment costs, and provides a reasonably accurate estimate of σ c .

Neighborhood food environment role in modifying psychosocial stress-diet relationships

PubMed Central

Zenk, Shannon N.; Schulz, Amy J.; Izumi, Betty T.; Mentz, Graciela; Israel, Barbara A.; Lockett, Murlisa

2013-01-01

Exposure to highly palatable foods may increase eating in response to stress, but this behavioral response has not been examined in relation to the neighborhood food environment. This study examined whether the neighborhood food environment modified relationships between psychosocial stress and dietary behaviors. Probability-sample survey (n=460) and in-person food environment audit data were used. Dietary behaviors were measured using 17 snack food items and a single eating-out-of-home item. Chronic stress was derived from five subscales; major life events was a count of 9 items. The neighborhood food environment was measured as availability of large grocery stores, small grocery stores, and convenience stores, as well as proportion of restaurants that were fast food. Two-level hierarchical regression models were estimated. Snack food intake was positively associated with convenience store availability and negatively associated with large grocery store availability. The measures of chronic stress and major life events were generally not associated with either dietary behavior overall, although Latinos were less likely to eat out at high levels of major life events than African Americans. Stress-neighborhood food environment interactions were not statistically significant. Important questions remain regarding the role of the neighborhood food environment in the stress-diet relationship that warrant further investigation. PMID:23415977

Fireman's lamp

NASA Technical Reports Server (NTRS)

Britz, W. J.; Varnedoe, W. W., Jr.

1977-01-01

Rugged lamp used by miners is adapted for firefighters by utilization of smaller, rechargeable 3-hour-life gel-cell battery. Lighter, maintenance free unit can be clipped to outer clothing for convenience. Small monitor circuit indicates need to recharge battery.

Childhood Reports of Food Neglect and Impulse Control Problems and Violence in Adulthood

PubMed Central

Vaughn, Michael G.; Salas-Wright, Christopher P.; Naeger, Sandra; Huang, Jin; Piquero, Alex R.

2016-01-01

Food insecurity and hunger during childhood are associated with an array of developmental problems in multiple domains, including impulse control problems and violence. Unfortunately, extant research is based primarily on small convenience samples and an epidemiological assessment of the hunger-violence link is lacking. The current study employed data from Wave 1 (2001–2002) and Wave 2 (2004–2005) of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). The NESARC is a nationally representative sample of non-institutionalized U.S. residents aged 18 years and older. Participants who experienced frequent hunger during childhood had significantly greater impulsivity, worse self-control, and greater involvement in several forms of interpersonal violence. These effects were stronger among whites, Hispanics, and males. The findings support general theoretical models implicating impulse control problems as a key correlate of crime and violence and add another facet to the importance of ameliorating food neglect in the United States. PMID:27043598

Butch/Femme Differences in Substance Use and Abuse Among Young Lesbian and Bisexual Women: Examination and Potential Explanations

PubMed Central

Rosario, Margaret; Schrimshaw, Eric W.; Hunter, Joyce

2011-01-01

The current study examined the role of gender atypical self-presentation on the alcohol, tobacco, and marijuana use, as well as symptoms of substance abuse, of an ethnically diverse sample of 76 young (ages 14 – 21 years) lesbian and bisexual women who were interviewed between 1993-95 in New York City. Even after controlling for age, sexual identity, and social desirability, young butch women reported drinking alcohol more frequently and in greater quantity, smoking more cigarettes, and using marijuana more frequently than young femme women. Experiences of gay-related stressful events, internalized homophobia, and emotional distress were found to largely account for the butch/femme differences in tobacco and marijuana use, but not in higher levels of alcohol use. Despite the small convenience sample, these findings suggest that intervention efforts to address the higher levels of substance use among young lesbian and bisexual women may increase effectiveness by also addressing experiences of gay-related stress and emotional distress of young butch women. PMID:18649226

Determination of polycyclic aromatic hydrocarbons in kerosene and bio-kerosene soot.

PubMed

Andrade-Eiroa, Auréa; Leroy, Valérie; Dagaut, Philippe; Bedjanian, Yuri

2010-03-01

Here we report a new, efficient and reliable analytical methodology for sensitive and selective quantification of Polycyclic Aromatic Hydrocarbons (PAHs) in soot samples. The methodology developed is based on ultrasonic extraction of the soot-bound PAHs into small volumes of acetonitrile, purification of the extracts through C(18) Solid Phase Extraction (SPE) cartridges and analysis by Reverse Phase Liquid Chromatography (RPLC) with UV and fluorimetric detection. For the first time, we report the convenience of adapting the SPE procedure to the nature of the soot samples. As a matter of fact, extracts containing high percentage of unpolar material are recommended to be cleaned with acetone, whereas extracts poor in unpolar compounds can be efficiently cleaned with methanol. The method was satisfactorily applied to kerosene and bio-kerosene soot from atmospheric open diffusion flames (pool fires) and premixed flames achieving Quantification and Detection limits in the range ng mg(-1) soot and recoveries about 90% for most of the PAHs studied. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Convenience stores surrounding urban schools: an assessment of healthy food availability, advertising, and product placement.

PubMed

Gebauer, Hilary; Laska, Melissa Nelson

2011-08-01

Adolescent obesity is a national public health problem, particularly among urban populations. Recent evidence has linked neighborhood food environments to health and nutrition status, with easier access to convenience stores being associated with increased risk for obesity. Little is known about the availability of healthy purchasing options within small, urban food stores, or the extent to which these factors are relevant to youth. The objective of this research was to characterize various features of the food environment within small convenience stores located nearby urban junior high and high schools. In-store audits were conducted in 63 stores located within 800 m of 36 urban Minnesota public secondary schools. Results indicated that a limited number of healthier beverages (i.e., water and 100% fruit juice) and snack options (i.e., nuts and pretzels) were available at most stores (≥85%). However, a wide range of healthy snack options were typically not available, with many specific items stocked in less than half of stores (e.g., low-fat yogurt in 27% of stores and low-fat granola bars in 43%). Overall, 51% of stores had fresh fruit and 49% had fresh vegetables. Few stores carried a range of healthier snack alternatives in single-serving packages. All stores had less healthful impulse purchase items available (e.g., candy) while only 46% carried healthier impulse items (e.g., fruit). Most stores (97%) had food/beverage advertising. Overall, convenience stores located in close proximity to secondary schools represent an important and understudied component of the youth food environment.

Facile high-throughput forward chemical genetic screening by in situ monitoring of glucuronidase-based reporter gene expression in Arabidopsis thaliana

PubMed Central

Halder, Vivek; Kombrink, Erich

2015-01-01

The use of biologically active small molecules to perturb biological functions holds enormous potential for investigating complex signaling networks. However, in contrast to animal systems, the search for and application of chemical tools for basic discovery in the plant sciences, generally referred to as “chemical genetics,” has only recently gained momentum. In addition to cultured cells, the well-characterized, small-sized model plant Arabidopsis thaliana is suitable for cultivation in microplates, which allows employing diverse cell- or phenotype-based chemical screens. In such screens, a chemical's bioactivity is typically assessed either through scoring its impact on morphological traits or quantifying molecular attributes such as enzyme or reporter activities. Here, we describe a facile forward chemical screening methodology for intact Arabidopsis seedlings harboring the β-glucuronidase (GUS) reporter by directly quantifying GUS activity in situ with 4-methylumbelliferyl-β-D-glucuronide (4-MUG) as substrate. The quantitative nature of this screening assay has an obvious advantage over the also convenient histochemical GUS staining method, as it allows application of statistical procedures and unbiased hit selection based on threshold values as well as distinction between compounds with strong or weak bioactivity. At the same time, the in situ bioassay is very convenient requiring less effort and time for sample handling in comparison to the conventional quantitative in vitro GUS assay using 4-MUG, as validated with several Arabidopsis lines harboring different GUS reporter constructs. To demonstrate that the developed assays is particularly suitable for large-scale screening projects, we performed a pilot screen for chemical activators or inhibitors of salicylic acid-mediated defense signaling using the Arabidopsis PR1p::GUS line. Importantly, the screening methodology provided here can be adopted for any inducible GUS reporter line. PMID:25688251

Revealing the values behind convenience food consumption.

PubMed

Botonaki, Anna; Mattas, Konstadinos

2010-12-01

The increasing importance of convenience in consumer food choices has attracted researchers' interest. In the effort to understand how convenience affects consumers' food preferences, values are believed to play an important role. The present study attempts to examine the way personal values suggested by Schwartz (1992) are associated with behaviour and attitudes regarding convenience food. A number of constructs describing food related attitudes and behaviours were developed and their relationship with personal values was analyzed following the methodology proposed by Brunsø, Scholderer, and Grunert (2004). Data were collected through a questionnaire survey from a random sample of consumers in Thessaloniki city, Greece. The results reveal that convenience food consumption and convenience orientation in the food domain are mainly connected with values that motivate people to seek new experiences, act independently and enhance their own personal interests, while are in conflict with values of conservation and self-transcendence. The opposite holds for other food related attitudes and behaviours like involvement with cooking and variety in diet. The findings seem to be of particular interest not only for marketers of food products, but also for food policy makers. Copyright © 2010 Elsevier Ltd. All rights reserved.

A matched case-control study of convenience store robbery risk factors.

PubMed

Hendricks, S A; Landsittel, D P; Amandus, H E; Malcan, J; Bell, J

1999-11-01

Convenience store clerks have been shown to be at high risk for assault and homicide, mostly owing to robbery or robbery attempts. Although the literature consistently indicates that at least some environmental designs are effective deterrents of robbery, the significance of individual interventions and policies has differed across past studies. To address these issues, a matched case-control study of 400 convenience store robberies in three metropolitan areas of Virginia was conducted. Conditional logistic regression was implemented to evaluate the significance of various environmental designs and other factors possibly related to convenience store robbery. Findings indicate that numerous characteristics of the surrounding environment and population were significantly associated with convenience store robbery. Results also showed that, on a univariate level, most crime prevention factors were significantly associated with a lower risk for robbery. Using a forward selection process, a multivariate model, which included cash handling policy, bullet-resistant shielding, and numerous characteristics of the surrounding area and population, was identified. This study addressed numerous limitations of the previous literature by prospectively collecting extensive data on a large sample of diverse convenience stores and directly addressing the current theory on the robbers' selection of a target store through a matched case-control design.

Development of a Micro-Fabricated Total-Field Magnetometer

DTIC Science & Technology

2011-03-01

are made with fluxgate technologies. Fluxgates have lower sensitivity than Cs magnetometers , yet they continue to be used in small wands simply...extraction process by providing the sensitivity of a Cs magnetometer with the convenience and low cost of a fluxgate wand. Extremely small and low cost...FINAL REPORT Development of a Micro-Fabricated Total-Field Magnetometer SERDP Project MR-1512 MARCH 2011 Mark Prouty Geometrics, Inc

Microfluidic device for a rapid immobilization of zebrafish larvae in environmental scanning electron microscopy.

PubMed

Akagi, Jin; Zhu, Feng; Skommer, Joanna; Hall, Chris J; Crosier, Philip S; Cialkowski, Michal; Wlodkowic, Donald

2015-03-01

Small vertebrate model organisms have recently gained popularity as attractive experimental models that enhance our understanding of human tissue and organ development. Despite a large body of evidence using optical spectroscopy for the characterization of small model organism on chip-based devices, no attempts have been so far made to interface microfabricated technologies with environmental scanning electron microscopy (ESEM). Conventional scanning electron microscopy requires high vacuum environments and biological samples must be, therefore, submitted to many preparative procedures to dehydrate, fix, and subsequently stain the sample with gold-palladium deposition. This process is inherently low-throughput and can introduce many analytical artifacts. This work describes a proof-of-concept microfluidic chip-based system for immobilizing zebrafish larvae for ESEM imaging that is performed in a gaseous atmosphere, under low vacuum mode and without any need for sample staining protocols. The microfabricated technology provides a user-friendly and simple interface to perform ESEM imaging on zebrafish larvae. Presented lab-on-a-chip device was fabricated using a high-speed infrared laser micromachining in a biocompatible poly(methyl methacrylate) thermoplastic. It consisted of a reservoir with multiple semispherical microwells designed to hold the yolk of dechorionated zebrafish larvae. Immobilization of the larvae was achieved by a gentle suction generated during blotting of the medium. Trapping region allowed for multiple specimens to be conveniently positioned on the chip-based device within few minutes for ESEM imaging. © 2014 International Society for Advancement of Cytometry.

THREE-PEE SAMPLING THEORY and program 'THRP' for computer generation of selection criteria

Treesearch

L. R. Grosenbaugh

1965-01-01

Theory necessary for sampling with probability proportional to prediction ('three-pee,' or '3P,' sampling) is first developed and then exemplified by numerical comparisons of several estimators. Program 'T RP' for computer generation of appropriate 3P-sample-selection criteria is described, and convenient random integer dispensers are...

Sampling Methodologies for Epidemiologic Surveillance of Men Who Have Sex with Men and Transgender Women in Latin America: An Empiric Comparison of Convenience Sampling, Time Space Sampling, and Respondent Driven Sampling

PubMed Central

Clark, J. L.; Konda, K. A.; Silva-Santisteban, A.; Peinado, J.; Lama, J. R.; Kusunoki, L.; Perez-Brumer, A.; Pun, M.; Cabello, R.; Sebastian, J. L.; Suarez-Ognio, L.; Sanchez, J.

2014-01-01

Alternatives to convenience sampling (CS) are needed for HIV/STI surveillance of most-at-risk populations in Latin America. We compared CS, time space sampling (TSS), and respondent driven sampling (RDS) for recruitment of men who have sex with men (MSM) and transgender women (TW) in Lima, Peru. During concurrent 60-day periods from June–August, 2011, we recruited MSM/TW for epidemiologic surveillance using CS, TSS, and RDS. A total of 748 participants were recruited through CS, 233 through TSS, and 127 through RDS. The TSS sample included the largest proportion of TW (30.7 %) and the lowest percentage of subjects who had previously participated in HIV/STI research (14.9 %). The prevalence of newly diagnosed HIV infection, according to participants’ self-reported previous HIV diagnosis, was highest among TSS recruits (17.9 %) compared with RDS (12.6 %) and CS (10.2 %). TSS identified diverse populations of MSM/TW with higher prevalences of HIV/STIs not accessed by other methods. PMID:24362754

Sampling methodologies for epidemiologic surveillance of men who have sex with men and transgender women in Latin America: an empiric comparison of convenience sampling, time space sampling, and respondent driven sampling.

PubMed

Clark, J L; Konda, K A; Silva-Santisteban, A; Peinado, J; Lama, J R; Kusunoki, L; Perez-Brumer, A; Pun, M; Cabello, R; Sebastian, J L; Suarez-Ognio, L; Sanchez, J

2014-12-01

Alternatives to convenience sampling (CS) are needed for HIV/STI surveillance of most-at-risk populations in Latin America. We compared CS, time space sampling (TSS), and respondent driven sampling (RDS) for recruitment of men who have sex with men (MSM) and transgender women (TW) in Lima, Peru. During concurrent 60-day periods from June-August, 2011, we recruited MSM/TW for epidemiologic surveillance using CS, TSS, and RDS. A total of 748 participants were recruited through CS, 233 through TSS, and 127 through RDS. The TSS sample included the largest proportion of TW (30.7 %) and the lowest percentage of subjects who had previously participated in HIV/STI research (14.9 %). The prevalence of newly diagnosed HIV infection, according to participants' self-reported previous HIV diagnosis, was highest among TSS recruits (17.9 %) compared with RDS (12.6 %) and CS (10.2 %). TSS identified diverse populations of MSM/TW with higher prevalences of HIV/STIs not accessed by other methods.

Convenient yet not a convenience sample: Jury pools as experimental subject pools.

PubMed

Murray, Gregg R; Rugeley, Cynthia R; Mitchell, Dona-Gene; Mondak, Jeffery J

2013-01-01

Scholars greatly benefit from access to convenient, inexpensive data sources. Many researchers rely on student subject pools, a practice that raises concern about the "college sophomore problem," or the possibility that findings from student subjects do not generalize beyond the campus. As an accessible, low cost, and heterogeneous data source, some researchers have used subjects recruited from jury pools, which are drawn from randomly-selected citizens required by law to appear for jury duty. In this paper, we discuss the strengths and weaknesses of this approach. First, we review pragmatic considerations involving access to jury pools, substantive content, the administration of survey-experiments, and the financial costs and benefits of this approach. Next, we present evidence regarding the quality of jury pool samples in terms of response rates, diversity, and representativeness. We conclude that jury pools, given proper attention to their limitations, offer an attractive addition to the viable sources of experimental data. Copyright © 2012 Elsevier Inc. All rights reserved.

Uniform Sampling Table Method and its Applications II--Evaluating the Uniform Sampling by Experiment.

PubMed

Chen, Yibin; Chen, Jiaxi; Chen, Xuan; Wang, Min; Wang, Wei

2015-01-01

A new method of uniform sampling is evaluated in this paper. The items and indexes were adopted to evaluate the rationality of the uniform sampling. The evaluation items included convenience of operation, uniformity of sampling site distribution, and accuracy and precision of measured results. The evaluation indexes included operational complexity, occupation rate of sampling site in a row and column, relative accuracy of pill weight, and relative deviation of pill weight. They were obtained from three kinds of drugs with different shape and size by four kinds of sampling methods. Gray correlation analysis was adopted to make the comprehensive evaluation by comparing it with the standard method. The experimental results showed that the convenience of uniform sampling method was 1 (100%), odds ratio of occupation rate in a row and column was infinity, relative accuracy was 99.50-99.89%, reproducibility RSD was 0.45-0.89%, and weighted incidence degree exceeded the standard method. Hence, the uniform sampling method was easy to operate, and the selected samples were distributed uniformly. The experimental results demonstrated that the uniform sampling method has good accuracy and reproducibility, which can be put into use in drugs analysis.

Credit Building in IDA Programs: Early Findings of a Longitudinal Study

ERIC Educational Resources Information Center

Birkenmaier, Julie; Curley, Jami; Kelly, Patrick

2012-01-01

Objective: This article reports on the impact of the Individual Development Account (IDA) program on credit. Method: Using a convenience sample of IDA participants (N = 165), data were analyzed using paired sample "t" tests, independent sample "t" test, one-way analysis of variance, Mann-Whitney "U" Tests, and…

Techniques For Measuring Absorption Coefficients In Crystalline Materials

NASA Astrophysics Data System (ADS)

Klein, Philipp H.

1981-10-01

Absorption coefficients smaller than 0.001 cm-1 can, with more or less difficulty, be measured by several techniques. With diligence, all methods can be refined to permit measurement of absorption coefficients as small as 0.00001 cm-1. Spectral data are most readily obtained by transmission (spectrophotometric) methods, using multiple internal reflection to increase effective sample length. Emissivity measurements, requiring extreme care in the elimination of detector noise and stray light, nevertheless afford the most accessible spectral data in the 0.0001 to 0.00001 cm-1 range. Single-wavelength informa-tion is most readily obtained with modifications of laser calorimetry. Thermo-couple detection of energy absorbed from a laser beam is convenient, but involves dc amplification techniques and is susceptible to stray-light problems. Photoacoustic detection, using ac methods, tends to diminish errors of these types, but at some expense in experimental complexity. Laser calorimetry has been used for measurements of absorption coefficients as small as 0.000003 cm-1. Both transmission and calorimetric data, taken as functions of intensity, have been used for measurement of nonlinear absorption coefficients.

A self-sampling method to obtain large volumes of undiluted cervicovaginal secretions.

PubMed

Boskey, Elizabeth R; Moench, Thomas R; Hees, Paul S; Cone, Richard A

2003-02-01

Studies of vaginal physiology and pathophysiology sometime require larger volumes of undiluted cervicovaginal secretions than can be obtained by current methods. A convenient method for self-sampling these secretions outside a clinical setting can facilitate such studies of reproductive health. The goal was to develop a vaginal self-sampling method for collecting large volumes of undiluted cervicovaginal secretions. A menstrual collection device (the Instead cup) was inserted briefly into the vagina to collect secretions that were then retrieved from the cup by centrifugation in a 50-ml conical tube. All 16 women asked to perform this procedure found it feasible and acceptable. Among 27 samples, an average of 0.5 g of secretions (range, 0.1-1.5 g) was collected. This is a rapid and convenient self-sampling method for obtaining relatively large volumes of undiluted cervicovaginal secretions. It should prove suitable for a wide range of assays, including those involving sexually transmitted diseases, microbicides, vaginal physiology, immunology, and pathophysiology.

Radar Doppler Processing with Nonuniform Sampling.

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

Doerry, Armin W.

2017-07-01

Conventional signal processing to estimate radar Doppler frequency often assumes uniform pulse/sample spacing. This is for the convenience of t he processing. More recent performance enhancements in processor capability allow optimally processing nonuniform pulse/sample spacing, thereby overcoming some of the baggage that attends uniform sampling, such as Doppler ambiguity and SNR losses due to sidelobe control measures.

The role of affect-driven impulsivity in gambling cognitions: A convenience-sample study with a Spanish version of the Gambling-Related Cognitions Scale.

PubMed

Del Prete, Francesco; Steward, Trevor; Navas, Juan F; Fernández-Aranda, Fernando; Jiménez-Murcia, Susana; Oei, Tian P S; Perales, José C

2017-03-01

Background and aims Abnormal cognitions are among the most salient domain-specific features of gambling disorder. The aims of this study were: (a) to examine and validate a Spanish version of the Gambling-Related Cognitions Scale (GRCS; Raylu & Oei, 2004) and (b) to examine associations between cognitive distortion levels, impulsivity, and gambling behavior. Methods This study first recruited a convenience sample of 500 adults who had gambled during the previous year. Participants were assessed using the Spanish version of GRCS (GRCS-S) questionnaire, the UPPS-P impulsivity questionnaire, measures of gambling behavior, and potentially relevant confounders. Robust confirmatory factor analysis methods on half the sample were used to select the best models from a hypothesis-driven set. The best solutions were validated on the other half, and the resulting factors were later correlated with impulsivity dimensions (in the whole n = 500 factor analysis sample) and clinically relevant gambling indices (in a separate convenience sample of 137 disordered and non-disordered gamblers; validity sample). Results This study supports the original five-factor model, suggests an alternative four-factor solution, and confirms the psychometric soundness of the GRCS-S. Importantly, cognitive distortions consistently correlated with affect- or motivation-driven aspects of impulsivity (urgency and sensation seeking), but not with cognitive impulsivity (lack of premeditation and lack of perseverance). Discussion and conclusions Our findings suggest that the GRCS-S is a valid and reliable instrument to identify gambling cognitions in Spanish samples. Our results expand upon previous research signaling specific associations between gambling-related distortions and affect-driven impulsivity in line with models of motivated reasoning.

The role of affect-driven impulsivity in gambling cognitions: A convenience-sample study with a Spanish version of the Gambling-Related Cognitions Scale

PubMed Central

Del Prete, Francesco; Steward, Trevor; Navas, Juan F.; Fernández-Aranda, Fernando; Jiménez-Murcia, Susana; Oei, Tian P. S.; Perales, José C.

2017-01-01

Background and aims Abnormal cognitions are among the most salient domain-specific features of gambling disorder. The aims of this study were: (a) to examine and validate a Spanish version of the Gambling-Related Cognitions Scale (GRCS; Raylu & Oei, 2004) and (b) to examine associations between cognitive distortion levels, impulsivity, and gambling behavior. Methods This study first recruited a convenience sample of 500 adults who had gambled during the previous year. Participants were assessed using the Spanish version of GRCS (GRCS-S) questionnaire, the UPPS-P impulsivity questionnaire, measures of gambling behavior, and potentially relevant confounders. Robust confirmatory factor analysis methods on half the sample were used to select the best models from a hypothesis-driven set. The best solutions were validated on the other half, and the resulting factors were later correlated with impulsivity dimensions (in the whole n = 500 factor analysis sample) and clinically relevant gambling indices (in a separate convenience sample of 137 disordered and non-disordered gamblers; validity sample). Results This study supports the original five-factor model, suggests an alternative four-factor solution, and confirms the psychometric soundness of the GRCS-S. Importantly, cognitive distortions consistently correlated with affect- or motivation-driven aspects of impulsivity (urgency and sensation seeking), but not with cognitive impulsivity (lack of premeditation and lack of perseverance). Discussion and conclusions Our findings suggest that the GRCS-S is a valid and reliable instrument to identify gambling cognitions in Spanish samples. Our results expand upon previous research signaling specific associations between gambling-related distortions and affect-driven impulsivity in line with models of motivated reasoning. PMID:28118729

Awareness and Perceptions of Food Safety Risks and Risk Management in Poultry Production and Slaughter: A Qualitative Study of Direct-Market Poultry Producers in Maryland.

PubMed

Baron, Patrick; Frattaroli, Shannon

2016-01-01

The objective of this study was to document and understand the perceptions and opinions of small-scale poultry producers who market directly to consumers about microbial food safety risks in the poultry supply chain. Between January and November 2014, we conducted semi-structured, in-depth interviews with a convenience sample of 16 owner-operators of Maryland direct-market commercial poultry farms. Three overarching thematic categories emerged from these interviews that describe: 1) characteristics of Maryland direct-market poultry production and processing; 2) microbial food safety risk awareness and risk management in small-scale poultry production, slaughter and processing; and 3) motivations for prioritizing food safety in the statewide direct-market poultry supply chain. Key informants provided valuable insights on many topics relevant to evaluating microbial food safety in the Maryland direct-market poultry supply chain, including: direct-market poultry production and processing practices and models, perspectives on issues related to food safety risk management, perspectives on direct-market agriculture economics and marketing strategies, and ideas for how to enhance food safety at the direct-market level of the Maryland poultry supply chain. The findings have policy implications and provide insights into food safety in small-scale commercial poultry production, processing, distribution and retail. In addition, the findings will inform future food safety research on the small-scale US poultry supply chain.

Electrofluidic Circuit-Based Microfluidic Viscometer for Analysis of Newtonian and Non-Newtonian Liquids under Different Temperatures.

PubMed

Lee, Tse-Ang; Liao, Wei-Hao; Wu, Yi-Fan; Chen, Yeng-Long; Tung, Yi-Chung

2018-02-06

This paper reports a microfluidic viscometer with an integrated pressure sensor based on electrofluidic circuits, which are electrical circuits constructed by ionic liquid-filled microfluidic channels. The electrofluidic circuit provides a pressure-sensing scheme with great long-term and thermal stability. The viscosity of the tested fluidic sample is estimated by its flow resistance, which is a function of pressure drop, flow rate, and the geometry of the microfluidic channel. The viscometer can be exploited to measure viscosity of either Newtonian or non-Newtonian power-law fluid under various shear rates (3-500 1/s) and temperatures (4-70 °C) with small sample volume (less than 400 μL). The developed sensor-integrated microfluidic viscometer is made of poly(dimethylsiloxane) (PDMS) with transparent electrofluidic circuit, which makes it feasible to simultaneously image samples under tests. In addition, the entire device is disposable to prevent cross-contamination between samples, which is desired for various chemical and biomedical applications. In the experiments, viscosities of Newtonian fluids, glycerol water solutions with different concentrations and a mixture of pyrogallol and sodium hydroxide (NaOH), and non-Newtonian fluids, xanthan gum solutions and human blood samples, have been characterized. The results demonstrate that the developed microfluidic viscometer provides a convenient and useful platform for practical viscosity characterization of fluidic samples for a wide variety of applications.

Polybrominated diphenyl ether flame retardant concentrations in faeces from young children in Queensland, Australia and associations with environmental and behavioural factors.

PubMed

English, Karin; Chen, Yiqin; Toms, Leisa-Maree; Jagals, Paul; Ware, Robert S; Mueller, Jochen F; Sly, Peter D

2017-10-01

The aim of our study was to investigate children's exposure to the flame retardants polybrominated diphenyl ethers (PBDEs) by analysing faecal content, a non-invasive matrix, as well as responses to an exposure-assessment questionnaire. A convenience sample of 61 parents with children (aged >3 months to <2 years) completed an online pre-tested questionnaire and provided faecal samples for analysis by high resolution gas chromatography/mass spectrometry. BDE-209 was the dominant congener in faecal samples adjusted to 8.3ng/g dry weight (dw), with >80% samples above the limit of detection (LOD). BDE-47 (0.23ng/g dw) and BDE-153 (0.03ng/g dw) were each detected above the LOD in approximately 60% of samples. Age was associated with BDE-47 (-7%/month) and BDE-153 (-12%/month) concentrations in faeces, but not BDE-209. Other variables associated with PBDE concentrations included features of the home (carpet, pets) and behaviour (hand-to-mouth, removing shoes, using a car sunshade, frequency of walks outdoors). However, given the small sample size of this study additional research is required to confirm these findings. In this study we demonstrated that faeces may be a viable alternative to monitor human exposure to PBDEs, but further validation studies are required. Copyright © 2017. Published by Elsevier Inc.

Exploration of patients' readiness for an eHealth management program for chronic heart failure: a preliminary study.

PubMed

Nahm, Eun-Shim; Blum, Kay; Scharf, Barbara; Friedmann, Erika; Thomas, Sue; Jones, Deborah; Gottlieb, Stephen S

2008-01-01

Heart failure (HF) is a major public health problem in the United States. Approximately 5 million Americans are living with HF, and each year, 550,000 more are newly diagnosed. With recent, rapidly advancing technologies, many studies have examined the effects of technology-based HF management programs. Most of these studies focused on telemonitoring devices, lacking an aspect to motivate individuals to manage their own illnesses. This exploratory study was conducted to (1) examine the readiness of patients with HF in using an eHealth program that includes both telemonitoring and motivational components (ie, Web learning modules, eCommunication) and (2) assess the specific needs of patients with HF that can be addressed by a future eHealth program. This was a single group descriptive study using a convenience sample. A total of 44 patients with HF (mean age, 72.8 years; range, 55-85 years) were recruited from the pool of enrollees of the Medicare Coordinated Care Demonstration project for HF management that used only a telemonitoring component. Although only 10 participants were users, among 34 nonusers, 17 reported availability of Web access, and 15 reported that they would use the Internet if access and training were available. Overall, confidence for using telemonitoring devices and Web-based health modules was high, with means of 27 (range, 3-30) and 7.6 (range, 1-10), respectively. Confidence for learning health information using Web modules, however, was lower with a mean of 41.5 (range, 8-80). The 2 most highly rated health information needs were research findings (n = 41, 93.2%) and medication (n = 39, 88.6%). Most participants would like to have e-mail communication with healthcare providers. The findings showed the participants' high readiness to use the proposed eHealth program if access and training were provided. This study used a small convenience sample. Further studies are needed with larger, diverse samples.

Qualitative evaluation of an educational intervention to reduce medicolegal risks for medical doctors experiencing significantly more cases than their peers in the UK and Ireland

PubMed Central

Jolly, John; Bowie, Paul; Price, Julie; Mason, Matt; Dinwoodie, Mark

2018-01-01

Objectives The Medical Protection Society (MPS) is a leading protection organisation for healthcare professionals worldwide. In the UK and Ireland, a small minority of MPS members experience significantly more medicolegal cases than their peers and are invited to participate in a risk education (RE) remediation process. To understand more about this educational intervention, we sought to explore participating doctors’ views of their experiences of this process and identify self-reported performance improvements and what elements of the intervention could be improved. Design Qualitative semistructured telephone interviews with a convenience sample of doctors with significantly more medicolegal cases than their peers identified by MPS. Setting UK and Ireland MPS members. Participants A convenience sample of 20 general medical practitioners and hospital specialists from a total of 79 who completed the RE process (25.3% response rate), with a particular focus on the Member Risk Review programme, between November 2013 and October 2015. Results 19 participants were male and 16 were based in general medical (office) practice. Three key themes were generated: personal and professional impacts and actions (eg, member has taken action to reduce clinical workload); comprehension and validity of RE interventions (eg, risks were related to wider patient management); and feedback and proposals (eg, the supportive nature of the educational interventions should be clear from the start). A number of recommendations were made by participants to improve the RE process and enhance the educational experience. Conclusions The RE process was largely valued by participants with many reporting that participation led to some positive professional behaviour changes and improvements in practice processes and personal well-being. PMID:29678988

A convenient method for the quantitative determination of elemental sulfur in coal by HPLC analysis of perchloroethylene extracts

USGS Publications Warehouse

Buchanan, D.H.; Coombs, K.J.; Murphy, P.M.; Chaven, C.

1993-01-01

A convenient method for the quantitative determination of elemental sulfur in coal is described. Elemental sulfur is extracted from the coal with hot perchloroethylene (PCE) (tetrachloroethene, C2Cl4) and quantitatively determined by HPLC analysis on a C18 reverse-phase column using UV detection. Calibration solutions were prepared from sublimed sulfur. Results of quantitative HPLC analyses agreed with those of a chemical/spectroscopic analysis. The HPLC method was found to be linear over the concentration range of 6 ?? 10-4 to 2 ?? 10-2 g/L. The lower detection limit was 4 ?? 10-4 g/L, which for a coal sample of 20 g is equivalent to 0.0006% by weight of coal. Since elemental sulfur is known to react slowly with hydrocarbons at the temperature of boiling PCE, standard solutions of sulfur in PCE were heated with coals from the Argonne Premium Coal Sample program. Pseudo-first-order uptake of sulfur by the coals was observed over several weeks of heating. For the Illinois No. 6 premium coal, the rate constant for sulfur uptake was 9.7 ?? 10-7 s-1, too small for retrograde reactions between solubilized sulfur and coal to cause a significant loss in elemental sulfur isolated during the analytical extraction. No elemental sulfur was produced when the following pure compounds were heated to reflux in PCE for up to 1 week: benzyl sulfide, octyl sulfide, thiane, thiophene, benzothiophene, dibenzothiophene, sulfuric acid, or ferrous sulfate. A sluury of mineral pyrite in PCE contained elemental sulfur which increased in concentration with heating time. ?? 1993 American Chemical Society.

Prevalence of substandard and falsified artemisinin-based combination antimalarial medicines on Bioko Island, Equatorial Guinea.

PubMed

Kaur, Harparkash; Allan, Elizabeth Louise; Mamadu, Ibrahim; Hall, Zoe; Green, Michael D; Swamidos, Isabel; Dwivedi, Prabha; Culzoni, Maria Julia; Fernandez, Facundo M; Garcia, Guillermo; Hergott, Dianna; Monti, Feliciano

2017-01-01

Poor-quality artemisinin-containing antimalarials (ACAs), including falsified and substandard formulations, pose serious health concerns in malaria endemic countries. They can harm patients, contribute to the rise in drug resistance and increase the public's mistrust of health systems. Systematic assessment of drug quality is needed to gain knowledge on the prevalence of the problem, to provide Ministries of Health with evidence on which local regulators can take action. We used three sampling approaches to purchase 677 ACAs from 278 outlets on Bioko Island, Equatorial Guinea as follows: convenience survey using mystery client (n=16 outlets, 31 samples), full island-wide survey using mystery client (n=174 outlets, 368 samples) and randomised survey using an overt sampling approach (n=88 outlets, 278 samples). The stated active pharmaceutical ingredients (SAPIs) were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories. Content analysis showed 91.0% of ACAs were of acceptable quality, 1.6% were substandard and 7.4% falsified. No degraded medicines were detected. The prevalence of medicines without the SAPIs was higher for ACAs purchased in the convenience survey compared with the estimates obtained using the full island-wide survey-mystery client and randomised-overt sampling approaches. Comparable results were obtained for full island survey-mystery client and randomised overt. However, the availability of purchased artesunate monotherapies differed substantially according to the sampling approach used (convenience, 45.2%; full island-wide survey-mystery client, 32.6%; random-overt sampling approach, 21.9%). Of concern is that 37.1% (n=62) of these were falsified. Falsified ACAs were found on Bioko Island, with the prevalence ranging between 6.1% and 16.1%, depending on the sampling method used. These findings underscore the vital need for national authorities to track the scale of ineffective medicines that jeopardise treatment of life-threatening diseases and value of a representative sampling approach to obtain/measure the true prevalence of poor-quality medicines.

Lessons learned: wrong intraocular lens.

PubMed

Schein, Oliver D; Banta, James T; Chen, Teresa C; Pritzker, Scott; Schachat, Andrew P

2012-10-01

To report cases involving the placement of the wrong intraocular lens (IOL) at the time of cataract surgery where human error occurred. Retrospective small case series, convenience sample. Seven surgical cases. Institutional review of errors committed and subsequent improvements to clinical protocols. Lessons learned and changes in procedures adapted. The pathways to a wrong IOL are many but largely reflect some combination of poor surgical team communication, transcription error, lack of preoperative clarity in surgical planning or failure to match the patient, and IOL calculation sheet with 2 unique identifiers. Safety in surgery involving IOLs is enhanced both by strict procedures, such as an IOL-specific "time-out," and the fostering of a surgical team culture in which all members are encouraged to voice questions and concerns. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

A Study of Concept Mapping as an Instructional Intervention in an Undergraduate General Chemistry Calorimetry Laboratory

NASA Astrophysics Data System (ADS)

Stroud, Mary W.

This investigation, rooted in both chemistry and education, considers outcomes occurring in a small-scale study in which concept mapping was used as an instructional intervention in an undergraduate calorimetry laboratory. A quasi-experimental, multiple-methods approach was employed since the research questions posed in this study warranted the use of both qualitative and quantitative perspectives and evaluations. For the intervention group of students, a convenience sample, post-lab concept maps, written discussions, quiz responses and learning surveys were characterized and evaluated. Archived quiz responses for non-intervention students were also analyzed for comparison. Students uniquely constructed individual concept maps containing incorrect, conceptually correct and "scientifically thin" calorimetry characterizations. Students more greatly emphasized mathematical relationships and equations utilized during the calorimetry experiment; the meaning of calorimetry concepts was demonstrated to a lesser extent.

Rapid DNA extraction from dried blood spots on filter paper: potential applications in biobanking.

PubMed

Choi, Eun-Hye; Lee, Sang Kwang; Ihm, Chunhwa; Sohn, Young-Hak

2014-12-01

Dried blood spot (DBS) technology is a microsampling alternative to traditional plasma or serum sampling for pharmaco- or toxicokinetic evaluation. DBS technology has been applied to diagnostic screening in drug discovery, nonclinical, and clinical settings. We have developed an improved elution protocol involving boiling of blood spots dried on Whatman filter paper. The purpose of this study was to compare the quality, purity, and quantity of DNA isolated from frozen blood samples and DBSs. We optimized a method for extraction and estimation of DNA from blood spots dried on filter paper (3-mm FTA card). A single DBS containing 40 μL blood was used. DNA was efficiently extracted in phosphate-buffered saline (PBS) or Tris-EDTA (TE) buffer by incubation at 37°C overnight. DNA was stable in DBSs that were stored at room temperature or frozen. The housekeeping genes GAPDH and beta-actin were used as positive standards for polymerase chain reaction (PCR) validation of general diagnostic screening. Our simple and convenient DBS storage and extraction methods are suitable for diagnostic screening by using very small volumes of blood collected on filter paper, and can be used in biobanks for blood sample storage.

Fast automated dual-syringe based dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry for the determination of polycyclic aromatic hydrocarbons in environmental water samples.

PubMed

Guo, Liang; Tan, Shufang; Li, Xiao; Lee, Hian Kee

2016-03-18

An automated procedure, combining low density solvent based solvent demulsification dispersive liquid-liquid microextraction (DLLME) with gas chromatography-mass spectrometry analysis, was developed for the determination of polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. Capitalizing on a two-rail commercial autosampler, fast solvent transfer using a large volume syringe dedicated to the DLLME process, and convenient extract collection using a small volume microsyringe for better GC performance were enabled. Extraction parameters including the type and volume of extraction solvent, the type and volume of dispersive solvent and demulsification solvent, extraction and demulsification time, and the speed of solvent injection were investigated and optimized. Under the optimized conditions, the linearity ranged from 0.1 to 50 μg/L, 0.2 to 50 μg/L, and 0.5 to 50 μg/L, depending on the analytes. Limits of detection were determined to be between 0.023 and 0.058 μg/L. The method was applied to determine PAHs in environmental water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Teacher Efficacy Beliefs: A Case Study Investigation of Core Curriculum

ERIC Educational Resources Information Center

Brown, Natalie Marie

2017-01-01

The purpose of this qualitative case study was to understand how utilizing the Core Knowledge Sequence and aligned curricular resources influenced teachers' perceived self-efficacy for a sample of Arizona elementary charter school teachers. The sample for this study was a convenience sample of 15 elementary teachers, who were currently…

Robotic voltammetry with carbon nanotube-based sensors: a superb blend for convenient high-quality antimicrobial trace analysis.

PubMed

Theanponkrang, Somjai; Suginta, Wipa; Weingart, Helge; Winterhalter, Mathias; Schulte, Albert

2015-01-01

A new automated pharmacoanalytical technique for convenient quantification of redox-active antibiotics has been established by combining the benefits of a carbon nanotube (CNT) sensor modification with electrocatalytic activity for analyte detection with the merits of a robotic electrochemical device that is capable of sequential nonmanual sample measurements in 24-well microtiter plates. Norfloxacin (NFX) and ciprofloxacin (CFX), two standard fluoroquinolone antibiotics, were used in automated calibration measurements by differential pulse voltammetry (DPV) and accomplished were linear ranges of 1-10 μM and 2-100 μM for NFX and CFX, respectively. The lowest detectable levels were estimated to be 0.3±0.1 μM (n=7) for NFX and 1.6±0.1 μM (n=7) for CFX. In standard solutions or tablet samples of known content, both analytes could be quantified with the robotic DPV microtiter plate assay, with recoveries within ±4% of 100%. And recoveries were as good when NFX was evaluated in human serum samples with added NFX. The use of simple instrumentation, convenience in execution, and high effectiveness in analyte quantitation suggest the merger between automated microtiter plate voltammetry and CNT-supported electrochemical drug detection as a novel methodology for antibiotic testing in pharmaceutical and clinical research and quality control laboratories.

[Determination of four phenolic endocrine disruptors in environmental water samples by high performance liquid chromatography-fluorescence detection using dispersive liquid-liquid microextraction coupled with derivatization].

PubMed

Wang, Xiaoyan; Qi, Weimei; Zhao, Xian'en; Lü, Tao; Wang, Xiya; Zheng, Longfang; Yan, Yehao; You, Jinmao

2014-06-01

To achieve accurate, fast and sensitive detection of phenolic endocrine disruptors in small volume of environmental water samples, a method of dispersive liquid-liquid microextraction (DLLME) coupled with fluorescent derivatization was developed for the determination of bisphenol A, nonylphenol, octylphenol and 4-tert-octylphenol in environmental water samples by high performance liquid chromatography-fluorescence detection (HPLC-FLD). The DLLME and derivatization conditions were investigated, and the optimized DLLME conditions for small volume of environmental water samples (pH 4.0) at room temperature were as follows: 70 microL chloroform as extraction solvent, 400 microL acetonitrile as dispersing solvent, vortex mixing for 3 min, and then high-speed centrifugation for 2 min. Using 2-[2-(7H-dibenzo [a, g] carbazol-7-yl)-ethoxy] ethyl chloroformate (DBCEC-Cl) as precolumn derivatization reagent, the stable derivatives of the four phenolic endocrine disruptors were obtained in pH 10.5 Na2CO3-NaHCO3 buffer/acetonitrile at 50 degrees C for 3 min, and then separated within 10 min by HPLC-FLD. The limits of detection (LODs) were in the range of 0.9-1.6 ng/L, and the limits of quantification (LOQs) were in the range of 3.8-7.1 ng/L. This method had perfect linearity, precision and recovery results, and showed obvious advantages and practicality comparing to the previously reported methods. It is a convenient and validated method for the routine analysis of phenolic endocrine disruptors in waste water of paper mill, lake water, domestic wastewater, tap water, etc.

Psychiatric Disorders in a Sample of Saudi Arabian Adolescents with Sickle Cell Disease

ERIC Educational Resources Information Center

Amr, Mostafa Abdel-Monhem; Amin, Tarek Tawfik; Hablas, Hatem Refaat

2010-01-01

The objectives of this study were to determine the magnitude of psychiatric disorders and to define socio-demographic and disease-related risk factors in a sample of adolescents with SCD in Al-Hassa, Saudi Arabia. The sample consisted of 110 adolescents with SCD and a convenient sample of 202 adolescents without SCD as controls. Psychiatric…

Sealed magic angle spinning nuclear magnetic resonance probe and process for spectroscopy of hazardous samples

DOEpatents

Cho, Herman M.; Washton, Nancy M.; Mueller, Karl T.; Sears, Jr., Jesse A.; Townsend, Mark R.; Ewing, James R.

2016-06-14

A magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) probe is described that includes double containment enclosures configured to seal and contain hazardous samples for analysis. The probe is of a modular design that ensures containment of hazardous samples during sample analysis while preserving spin speeds for superior NMR performance and convenience of operation.

Soil moisture by extraction and gas chromatography

NASA Technical Reports Server (NTRS)

Merek, E. L.; Carle, G. C.

1973-01-01

To determine moisture content of soils rapidly and conveniently extract moisture with methanol and determine water content of methanol extract by gas chromatography. Moisture content of sample is calculated from weight of water and methanol in aliquot and weight of methanol added to sample.

Respondent-Driven Sampling: An Assessment of Current Methodology.

PubMed

Gile, Krista J; Handcock, Mark S

2010-08-01

Respondent-Driven Sampling (RDS) employs a variant of a link-tracing network sampling strategy to collect data from hard-to-reach populations. By tracing the links in the underlying social network, the process exploits the social structure to expand the sample and reduce its dependence on the initial (convenience) sample.The current estimators of population averages make strong assumptions in order to treat the data as a probability sample. We evaluate three critical sensitivities of the estimators: to bias induced by the initial sample, to uncontrollable features of respondent behavior, and to the without-replacement structure of sampling.Our analysis indicates: (1) that the convenience sample of seeds can induce bias, and the number of sample waves typically used in RDS is likely insufficient for the type of nodal mixing required to obtain the reputed asymptotic unbiasedness; (2) that preferential referral behavior by respondents leads to bias; (3) that when a substantial fraction of the target population is sampled the current estimators can have substantial bias.This paper sounds a cautionary note for the users of RDS. While current RDS methodology is powerful and clever, the favorable statistical properties claimed for the current estimates are shown to be heavily dependent on often unrealistic assumptions. We recommend ways to improve the methodology.

Barriers to acceptance of self-sampling for human papillomavirus across ethnolinguistic groups of women.

PubMed

Howard, Michelle; Lytwyn, Alice; Lohfeld, Lynne; Redwood-Campbell, Lynda; Fowler, Nancy; Karwalajtys, Tina

2009-01-01

Immigrant and low socio-economic (SES) women in North America underutilize Papanicolaou screening. Vaginal swab self-sampling for oncogenic human papillomavirus (HPV) has the potential to increase cervical cancer screening participation. The purpose of this qualitative study was to understand the perceptions of lower SES and immigrant women regarding self-sampling for HPV. Eleven focus-group interviews were conducted: one with Canadian-born English-speaking lower SES women, and two groups each with Arabic, Cantonese, Dari (Afghani), Somali and Spanish (Latino)-speaking women (one group conducted in English, the other in the native language) recently immigrated to Canada. Five to nine women aged 35 to 65 years and married with children participated in each group. Themes included 1) who might use self-sampling and why; 2) aversion to self-sampling and reasons to prefer physician; 3) ways to improve the appeal of self-sampling. Women generally perceived benefits of self-sampling and a small number felt they might use the method, but all groups had some reservations. Reasons included: uncertainty over performing the sampling correctly; fear of hurting themselves; concern about obtaining appropriate material; and concerns about test accuracy. Women preferred testing by a health care professional because they were accustomed to pelvic examinations, it was more convenient, or they trusted the results. Perceptions of self-sampling for HPV were similar across cultures and pertained to issues of confidence in self-sampling and need for physician involvement in care. These findings can inform programs and studies planning to employ self-sampling as a screening modality for cervical cancer.

Correlation between nicotine dependence and barriers to cessation between exclusive cigarette smokers and dual (water pipe) smokers among Arab Americans

PubMed Central

El-Shahawy, Omar; Haddad, Linda

2015-01-01

Background Evidence suggests that dual cigarette and water pipe use is growing among minority groups, particularly among Arab Americans. Differences in nicotine dependence and barriers to smoking cessation among such dual smokers have not been previously examined in this population. We examined potential differences that might exist between exclusive cigarette smokers and dual smokers (cigarette and water pipe) pertaining to nicotine dependence and barriers to cessation among Arab Americans. Methods We conducted a cross-sectional study using a convenience sample of self-identified Arab immigrant smokers (n=131) living in the Richmond, VA metropolitan area. Data were collected using four questionnaires: Demographic and Cultural Information questionnaire, Tobacco Use questionnaire, Fagerström Test for Nicotine Dependence (FTND) questionnaire, and Barriers to Cessation questionnaire. We examined differences in nicotine dependence and barriers to cessation between exclusive cigarette smokers and dual smokers of cigarettes and water pipe. Furthermore, we explored the correlations of these measures with select variables. Results There was a significant difference in the FTND scores between the exclusive cigarette smokers (mean M=2.55, standard deviation [SD] =2.10) and dual smokers (M=3.71, SD =2.42); t(129) = (2.51), P=0.0066. There was also a significant difference in the Barriers to Cessation scores between exclusive cigarette smokers (M=38.47, SD =13.07) and dual smokers (M=45.21, SD =9.27); t(129) = (2.56), P=0.0058. Furthermore, there was a highly significant correlation among FTND scores, Barriers to Cessation scores, and past quit attempts among dual smokers. Conclusion Water pipe tobacco smoking seems to be both adding to the dependence potential of cigarette smoking and enhancing barriers to cessation in our study sample. However, the high correlation between quit attempts, FTND, and barriers to cessation needs further investigation to ascertain the possible reasons behind it. This preliminary study utilized a cross-sectional survey among participants of a rather small convenience sample, especially in the dual smokers group. Thus, there is a need to examine these differences via a longitudinal design in a larger sample. PMID:25674035

Observational studies of patients in the emergency department: a comparison of 4 sampling methods.

PubMed

Valley, Morgan A; Heard, Kennon J; Ginde, Adit A; Lezotte, Dennis C; Lowenstein, Steven R

2012-08-01

We evaluate the ability of 4 sampling methods to generate representative samples of the emergency department (ED) population. We analyzed the electronic records of 21,662 consecutive patient visits at an urban, academic ED. From this population, we simulated different models of study recruitment in the ED by using 2 sample sizes (n=200 and n=400) and 4 sampling methods: true random, random 4-hour time blocks by exact sample size, random 4-hour time blocks by a predetermined number of blocks, and convenience or "business hours." For each method and sample size, we obtained 1,000 samples from the population. Using χ(2) tests, we measured the number of statistically significant differences between the sample and the population for 8 variables (age, sex, race/ethnicity, language, triage acuity, arrival mode, disposition, and payer source). Then, for each variable, method, and sample size, we compared the proportion of the 1,000 samples that differed from the overall ED population to the expected proportion (5%). Only the true random samples represented the population with respect to sex, race/ethnicity, triage acuity, mode of arrival, language, and payer source in at least 95% of the samples. Patient samples obtained using random 4-hour time blocks and business hours sampling systematically differed from the overall ED patient population for several important demographic and clinical variables. However, the magnitude of these differences was not large. Common sampling strategies selected for ED-based studies may affect parameter estimates for several representative population variables. However, the potential for bias for these variables appears small. Copyright © 2012. Published by Mosby, Inc.

Turnover among Filipino nurses in Ministry of Health hospitals in Saudi Arabia: causes and recommendations for improvement.

PubMed

Aljohani, Khalid Abdullah; Alomari, Omar

2018-01-01

Nurse turnover is a critical challenge for healthcare organizations as it results in a decreasing nurse/patient ratio and increasing costs. Identify factors influencing the termination of Filipino nurses in Ministry of Health (MOH) hospitals and record nurse recommendations to improve retention. Cross-sectional. Data was gathered from a convenience sample of Filipino nurses with previous experience in MOH hospitals in Saudi Arabia who attended recruitment interviews at the Saudi employment office in Manila. The sample included 124 nurses. Major turnover factors included low salary (18.3%), low nurse/patient ratio (15%), end of contract (14.5%), discrimination (13.5%), and bad accommodations (9%). Suggested areas of improvement included financial motivations (34%), administration support (25%), quality of life (25%), and work environment (16%). Managing nurse turnover can be implemented on the organizational as well as at MOH levels. The recommendations given by the participants provide direct targets to improve retention. With convenience sampling, the sample is probably not representative of the Filipino nursing population. None.

Validating a biometric authentication system: sample size requirements.

PubMed

Dass, Sarat C; Zhu, Yongfang; Jain, Anil K

2006-12-01

Authentication systems based on biometric features (e.g., fingerprint impressions, iris scans, human face images, etc.) are increasingly gaining widespread use and popularity. Often, vendors and owners of these commercial biometric systems claim impressive performance that is estimated based on some proprietary data. In such situations, there is a need to independently validate the claimed performance levels. System performance is typically evaluated by collecting biometric templates from n different subjects, and for convenience, acquiring multiple instances of the biometric for each of the n subjects. Very little work has been done in 1) constructing confidence regions based on the ROC curve for validating the claimed performance levels and 2) determining the required number of biometric samples needed to establish confidence regions of prespecified width for the ROC curve. To simplify the analysis that address these two problems, several previous studies have assumed that multiple acquisitions of the biometric entity are statistically independent. This assumption is too restrictive and is generally not valid. We have developed a validation technique based on multivariate copula models for correlated biometric acquisitions. Based on the same model, we also determine the minimum number of samples required to achieve confidence bands of desired width for the ROC curve. We illustrate the estimation of the confidence bands as well as the required number of biometric samples using a fingerprint matching system that is applied on samples collected from a small population.

Modeling the acceptance of clinical information systems among hospital medical staff: an extended TAM model.

PubMed

Melas, Christos D; Zampetakis, Leonidas A; Dimopoulou, Anastasia; Moustakis, Vassilis

2011-08-01

Recent empirical research has utilized the Technology Acceptance Model (TAM) to advance the understanding of doctors' and nurses' technology acceptance in the workplace. However, the majority of the reported studies are either qualitative in nature or use small convenience samples of medical staff. Additionally, in very few studies moderators are either used or assessed despite their importance in TAM based research. The present study focuses on the application of TAM in order to explain the intention to use clinical information systems, in a random sample of 604 medical staff (534 physicians) working in 14 hospitals in Greece. We introduce physicians' specialty as a moderator in TAM and test medical staff's information and communication technology (ICT) knowledge and ICT feature demands, as external variables. The results show that TAM predicts a substantial proportion of the intention to use clinical information systems. Findings make a contribution to the literature by replicating, explaining and advancing the TAM, whereas theory is benefited by the addition of external variables and medical specialty as a moderator. Recommendations for further research are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

Frequency distributions of helminths of wolves in Kazakhstan.

PubMed

Abdybekova, A M; Torgerson, P R

2012-03-23

Between 2001 and 2008 a total of 41 wolves (Canis lupus) were necropsied in southern Kazakhstan and their intestinal parasite fauna evaluated. Of these animals 8 (19.5%) were infected with Echinococcus granulosus, 15 (36%) with Taenia spp, 13 (31.7%) with Dypilidium caninum, 5 (12.2%) with Mesocestoides lineatus, 15 (36.6%) with Toxocara canis, 16 (39%) with Toxascaris leonina, 8 (19.5%) with Trichuris vulpis, 9 (22%) with Macracanthorhynchus catulinus and 1 (2.4%) with Moniliformis moniliformis. All parasites had an aggregated distribution which followed a zero inflated or hurdle model. Although a small convenience sample of wolves, the results indicate a high prevalence of infection with E. granulosus. The mean abundance (1275 E. granulosus per wolf) was high with individual infected wolves carrying intensities of several thousand parasites. As wolves are common in Kazakhstan they may act as an important host in the transmission of this zoonotic parasite. The wolves were sampled from an area of Kazakhstan where there is a high prevalence of hydatid cysts in livestock and where echinococcosis has been observed in wild ungulates. Copyright © 2011 Elsevier B.V. All rights reserved.

Identification of a Novel Human Papillomavirus by Metagenomic Analysis of Samples from Patients with Febrile Respiratory Illness

PubMed Central

Mokili, John L.; Dutilh, Bas E.; Lim, Yan Wei; Schneider, Bradley S.; Taylor, Travis; Haynes, Matthew R.; Metzgar, David; Myers, Christopher A.; Blair, Patrick J.; Nosrat, Bahador; Wolfe, Nathan D.; Rohwer, Forest

2013-01-01

As part of a virus discovery investigation using a metagenomic approach, a highly divergent novel Human papillomavirus type was identified in pooled convenience nasal/oropharyngeal swab samples collected from patients with febrile respiratory illness. Phylogenetic analysis of the whole genome and the L1 gene reveals that the new HPV identified in this study clusters with previously described gamma papillomaviruses, sharing only 61.1% (whole genome) and 63.1% (L1) sequence identity with its closest relative in the Papillomavirus episteme (PAVE) database. This new virus was named HPV_SD2 pending official classification. The complete genome of HPV-SD2 is 7,299 bp long (36.3% G/C) and contains 7 open reading frames (L2, L1, E6, E7, E1, E2 and E4) and a non-coding long control region (LCR) between L1 and E6. The metagenomic procedures, coupled with the bioinformatic methods described herein are well suited to detect small circular genomes such as those of human papillomaviruses. PMID:23554892

Bias of shear wave elasticity measurements in thin layer samples and a simple correction strategy.

PubMed

Mo, Jianqiang; Xu, Hao; Qiang, Bo; Giambini, Hugo; Kinnick, Randall; An, Kai-Nan; Chen, Shigao; Luo, Zongping

2016-01-01

Shear wave elastography (SWE) is an emerging technique for measuring biological tissue stiffness. However, the application of SWE in thin layer tissues is limited by bias due to the influence of geometry on measured shear wave speed. In this study, we investigated the bias of Young's modulus measured by SWE in thin layer gelatin-agar phantoms, and compared the result with finite element method and Lamb wave model simulation. The result indicated that the Young's modulus measured by SWE decreased continuously when the sample thickness decreased, and this effect was more significant for smaller thickness. We proposed a new empirical formula which can conveniently correct the bias without the need of using complicated mathematical modeling. In summary, we confirmed the nonlinear relation between thickness and Young's modulus measured by SWE in thin layer samples, and offered a simple and practical correction strategy which is convenient for clinicians to use.

Generalizability of causal inference in observational studies under retrospective convenience sampling.

PubMed

Hu, Zonghui; Qin, Jing

2018-05-20

Many observational studies adopt what we call retrospective convenience sampling (RCS). With the sample size in each arm prespecified, RCS randomly selects subjects from the treatment-inclined subpopulation into the treatment arm and those from the control-inclined into the control arm. Samples in each arm are representative of the respective subpopulation, but the proportion of the 2 subpopulations is usually not preserved in the sample data. We show in this work that, under RCS, existing causal effect estimators actually estimate the treatment effect over the sample population instead of the underlying study population. We investigate how to correct existing methods for consistent estimation of the treatment effect over the underlying population. Although RCS is adopted in medical studies for ethical and cost-effective purposes, it also has a big advantage for statistical inference: When the tendency to receive treatment is low in a study population, treatment effect estimators under RCS, with proper correction, are more efficient than their parallels under random sampling. These properties are investigated both theoretically and through numerical demonstration. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Testing the Self-Efficacy Questionnaire with Korean Children in Institutionalized Care

ERIC Educational Resources Information Center

Kim, Youngmi; Kim, Kyeongmo; Lee, Shinhye

2017-01-01

Purpose: We tested the reliability and validity of the Self-Efficacy Questionnaire for Children (SEQ-C) in a sample of children living in orphanages in South Korea. Methods: Our study sample consisted of 334 children aged 13-18 obtained using a convenience sampling method. We conducted a confirmatory factor analysis to identify the factor…

Pitless plum: reality or fantasy

USDA-ARS?s Scientific Manuscript database

Luther Burbank began a breeding program to produce stoneless plums (Prunus domestica) over 100 years ago. He released two plums, 'Miracle' and 'Conquest', whose fruit contained only a very small part of the stone. These plums are no longer available. In today's world of convenience, a plum that d...

40 CFR 63.1019 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

... leaks are placed here for administrative convenience and only apply to those owners and operators of... relief devices, sampling connection systems, open-ended valves or lines, valves, connectors...

A randomized controlled trial of cast versus splint for distal radial buckle fracture: an evaluation of satisfaction, convenience, and preference.

PubMed

Williams, Kristine G; Smith, Gillian; Luhmann, Scott J; Mao, Jingnan; Gunn, Joseph D; Luhmann, Janet D

2013-05-01

Buckle fractures are inherently stable and at low risk for displacement. These advantages allow for treatment options that may create confusion for the practitioner. Accepted immobilization methods include circumferential cast, plaster or prefabricated splint, and soft bandaging. Despite mounting evidence for splinting, the questions of pain, preference, satisfaction, and convenience offer a challenge to changing practice. The purposes of this study were (1) to compare cast versus splint for distal radial buckle fractures in terms of parental and patient satisfaction, convenience, and preference and (2) to compare pain reported for cast versus splint. We conducted a prospective randomized trial of a convenience sample of patients 2 through 17 years with a radiologically confirmed distal radial buckle fracture. Subjects were randomly assigned to short-arm cast or prefabricated wrist splint. We assessed satisfaction, convenience, preference, and pain in the emergency department and at days 1, 3, 7, and 21 after immobilization. Ninety-four patients were enrolled. Compared with the cast group, those in the splint group reported higher levels of satisfaction, preference, and convenience on 10-point visual analog scale. Although pain scores were higher for those in the splint group, the difference was not statistically significant. With the exception of pain reported in the emergency department being higher for the splinted group, all other measures, including convenience, satisfaction, and preference, showed a clear trend favoring splints at almost every time period in the study. This study provides additional evidence that splinting is preferable to casting for the treatment of distal radial buckle fractures.

Sibling Incest: Reports from Forty-One Survivors

ERIC Educational Resources Information Center

Carlson, Bonnie E.; Maciol, Katherine; Schneider, Joanne

2006-01-01

An exploratory study was conducted with a convenience sample of 41 adult survivors of sibling incest using a retrospective survey design. Participants were interviewed about their childhood sexual experiences with a sibling. Most participants reported vaginal or oral intercourse and coercive experiences. Half of the sample reported sexual…

Contamination risk of stable isotope samples during milling.

PubMed

Isaac-Renton, M; Schneider, L; Treydte, K

2016-07-15

Isotope analysis of wood is an important tool in dendrochronology and ecophysiology. Prior to mass spectrometry analysis, wood must be homogenized, and a convenient method involves a ball mill capable of milling samples directly in sample tubes. However, sample-tube plastic can contaminate wood during milling, which could lead to biological misinterpretations. We tested possible contamination of whole wood and cellulose samples during ball-mill homogenization for carbon and oxygen isotope measurements. We used a multi-factorial design with two/three steel milling balls, two sample amounts (10 mg, 40 mg), and two milling times (5 min, 10 min). We further analyzed abrasion by milling empty tubes, and measured the isotope ratios of pure contaminants. A strong risk exists for carbon isotope bias through plastic contamination: the δ(13) C value of polypropylene deviated from the control by -6.77‰. Small fibers from PTFE filter bags used during cellulose extraction also present a risk as the δ(13) C value of this plastic deviated by -5.02‰. Low sample amounts (10 mg) showed highest contamination due to increased abrasion during milling (-1.34‰), which is further concentrated by cellulose extraction (-3.38‰). Oxygen isotope measurements were unaffected. A ball mill can be used to homogenize samples within test tubes prior to oxygen isotope analysis, but not prior to carbon or radiocarbon isotope analysis. There is still a need for a fast, simple and contamination-free sample preparation procedure. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Conflicts of interest in Australia's IVF industry: an empirical analysis and call for action.

PubMed

Blakely, Brette; Williams, Jane; Mayes, Christopher; Kerridge, Ian; Lipworth, Wendy

2017-11-01

In Australia, the growing assisted reproductive technologies (ART) industry has recently received some public criticism. Much of this criticism centres on the concern that doctors are increasingly motivated by profit, rather than patient interests. These concerns appear to suggest that the growing business of ART generates conflicts of interest (COI) for clinicians. While media reports may be rhetorically compelling, claims that ART practice is distorted by COI must be supported by empirical evidence. This preliminary study sought to engage with people involved with the ART industry and map out their concerns related to COI in ART. A small convenience sample of eight professionals was interviewed. Here, we present the major themes uncovered, including a richer understanding of the 'interests' of various parties involved in Australian ART. We then propose a strategy for how this topic could be constructively explored.

The physical, behavioral, and psychosocial consequences of Internet use in college students.

PubMed

Clark, Deborah J; Frith, Karen H; Demi, Alice S

2004-01-01

The purposes of this study were to identify the physical, behavioral, and psychosocial consequences of Internet use in undergraduate college students; and to evaluate whether time, social norms, and adopter category predict the consequences of Internet use. Rogers' model for studying consequences of innovation was adapted for this study. A descriptive, correlational design was used. Convenience sampling yielded 293 undergraduate students who answered the online survey. Consequences of Internet use were assessed with the researcher-developed instrument, the Internet Consequences Scale (ICONS). Mean scores on the behavioral and psychosocial subscales of the ICONS indicated positive consequences of Internet use, while the physical consequences subscale revealed negative consequences. Multiple regression analyses revealed a small, but significant, amount of variance in consequences of Internet use that could be explained by time, social norms, and adopter category, thus supporting the adapted model for the study of consequences of Internet use in college students.

Exploring female GPs' perceptions about medical leadership.

PubMed

Price, Karen; Clearihan, Lynette

2015-06-01

Women are increasingly entering the Australian general practice workforce. This study aims to explore female general practitioners' (GPs') perceptions of possible barriers to leadership and professional roles in the workforce. A purposive, convenience sample of 30 female GPs in active practice was approached in February, 2012. An anonymous, pa-per-based, semi-quantitative survey sought to identify participation and leadership confidence within general practice in a number of professional roles. The top two barriers participants identified for after-hours medical meetings were energy to attend and geographical location. For after-hours care, the top two barriers identified were energy and self-motivation. Few participants aspired to 'leadership' activities. 'Medical mentoring' was most likely to attract them into leadership. It is important female GPs' perspectives are explored in general practice. This small survey suggests further studies are needed in the importance of energy limitations and lack of self-confidence in restricting female GPs' capacity to fully engage in professional roles.

Child Maltreatment Trauma, Posttraumatic Stress Disorder, and Cortisol Levels in Women: A Literature Review.

PubMed

Li, Yang; Seng, Julia S

Studies of the relationship between cortisol and posttraumatic stress disorder (PTSD) have had inconsistent results. Gender, trauma type, and age at trauma exposure may explain the inconsistencies. The objective of the review was to examine cortisol levels in relation to PTSD in women with a history of child maltreatment trauma. A review of literature found 13 articles eligible for inclusion. Despite limiting focus to the relatively homogeneous population, the patterns of associations between PTSD and cortisol levels were still inconsistent. The reasons for the inconsistencies likely include highly varied methods across studies, small convenience samples, and unmeasured neuroendocrine hormones that may be stronger predictors of PTSD. The review does not point to a clear bio-behavioral target for psychiatric nursing intervention. It is important to continue to address the developmental and clinical stress response aspects of child maltreatment trauma-related PTSD without assuming that these stress responses are hypothalamic-pituitary-adrenal-axis driven.

The effects of common medications on volumetric phallometry

PubMed Central

Lykins, Amy D.; Robinson, Jennifer J.; LeBlanc, Serge; Cantor, James M.

2015-01-01

Abstract Phallometry is a physiological measure of sexual response widely used for the assessment of paedophilia among sexual offenders. Although many medications decrease penile response sufficiently to interfere with sexual intercourse, it is unknown to what extent such medications might interfere with phallometric testing. In the current study, we utilized a naturalistic convenience sample of 1078 men who attended a clinic for assessment of sexual preferences, mostly related to sexual offence convictions. In the present analyses, we quantified the differences in penile response during phallometric assessment associated with taking a range of common medications. Participants on medication typically showed less penile output than participants not taking medications; however, differences were largely accounted for by age rather than by medication status. Though most medications were associated with decreases in penile responsivity during volumetric phallometric testing, such changes were small in absolute terms and appeared to be associated with ageing rather than with the medications themselves. PMID:26549976

Effects of Pride and Regret on Geriatric Depression: A Cross-Cultural Study With Mixed-Methods Approaches.

PubMed

Lee, Othelia E; Ryu, Seungah

2018-03-01

Pride and regret are self-conscious emotions that develop later in life and become a source of emotional struggle. This cross-cultural study examined the effect of the content and intensity of self-conscious emotions on Geriatric Depression Scale (GDS) scores. Among a convenience sample of 234 older adults (130 in the United States and 104 in South Korea), the contents and intensities of both life regrets and pride were examined. Although a greater variety of regrets was cited by Americans, overall Korean respondents reported higher intensity of regret. Regrets that were related to leisure and addiction among Americans and health and career among Koreans were predictors of the GDS scores. Pride in leisure activities for Americans and altruism among Koreans could alleviate depression. While regrets and pride explained a small amount of the variance in the GDS scores, current life stressors greatly contributed to geriatric depression.

Circadian rhythms and sleep patterns in urban Greek couples.

PubMed

Lee, Kathryn A; Beyene, Yewoubdar; Paparrigopoulos, Thomas J; Dikeos, Dimitris G; Soldatos, Constantin R

2007-07-01

A convenience sample of 14 adults (seven couples) who intentionally nap regularly was recruited to describe circadian rhythms and sleep patterns in a culture in which afternoon naps are routine. Participants wore a wrist actigraph for 48 hr during May to obtain two peaks and troughs of activity data. Peak activity, estimated by cosinor analysis (acrophase), occurred at 1542 hours for men and at 1600 hours for women. Compared to their male partners, women had a later acrophase and a significantly stronger 24-hr rhythm, despite similar nap and nighttime sleep schedules. Men had more awakenings during the night and slightly shorter naps than did women. For the 24-hr period, men averaged 6.8 +/- 1.0 hr of sleep and women averaged 7.4 +/- 1.1 hr. Results indicate that Greek adults delay sleep onset at night and awaken early in the morning. Among this small group, naps are an accepted cultural behavior.

Construct validity of the Moral Development Scale for Professionals (MDSP).

PubMed

Söderhamn, Olle; Bjørnestad, John Olav; Skisland, Anne; Cliffordson, Christina

2011-01-01

The aim of this study was to investigate the construct validity of the Moral Development Scale for Professionals (MDSP) using structural equation modeling. The instrument is a 12-item self-report instrument, developed in the Scandinavian cultural context and based on Kohlberg's theory. A hypothesized simplex structure model underlying the MDSP was tested through structural equation modeling. Validity was also tested as the proportion of respondents older than 20 years that reached the highest moral level, which according to the theory should be small. A convenience sample of 339 nursing students with a mean age of 25.3 years participated. Results confirmed the simplex model structure, indicating that MDSP reflects a moral construct empirically organized from low to high. A minority of respondents >20 years of age (13.5%) scored more than 80% on the highest moral level. The findings support the construct validity of the MDSP and the stages and levels in Kohlberg's theory.

Aluminium-gold reference material for the k0-standardisation of neutron activation analysis

NASA Astrophysics Data System (ADS)

Ingelbrecht, C.; Peetermans, F.; De Corte, F.; De Wispelaere, A.; Vandecasteele, C.; Courtijn, E.; D'Hondt, P.

1991-05-01

Gold is an excellent comparator material for the k0-standardisation of neutron activation analysis because of its convenient and well defined nuclear properties. The most suitable form for a reference material is a dilute aluminium-gold alloy, for which the self-shielding effect for neutrons is small. Castings of composition Al-0.1 wt.% Au were prepared by crucible-less levitation melting, which gives close control of ingot composition with minimal contamination of the melt. The alloy composition was checked using induction-coupled plasma source emission spectrometry. The homogeneity of the alloy was measured by neutron activation analysis and a relative standard deviation of the gold content of 0.30% was found (10 mg samples). Metallography revealed a homogeneous distribution of AuAl 2 particles. The alloy was certified as Reference Material CBNM-530, with certified gold mass fraction 0.100±0.002 wt.%.

Rising rates of labor induction: present concerns and future strategies.

PubMed

Rayburn, William F; Zhang, Jun

2002-07-01

The rate of labor induction nationwide increased gradually from 9.5% to 19.4% between 1990 and 1998. Reasons for this doubling of inductions relate to widespread availability of cervical ripening agents, pressure from patients, conveniences to physicians, and litigious constraints. The increase in medically indicated inductions was slower than the overall increase, suggesting that induction for marginal or elective reasons has risen more rapidly. Data to support or refute the benefits of marginal or elective inductions are limited. Many trials of inductions for marginal indications are either nonexistent or retrospective with small sample sizes, thereby limiting definitive conclusions. Until prospective clinical trials can better validate reasons for the liberal use of labor induction, it would seem prudent to maintain a cautious approach, especially among nulliparous women. Strategies are proposed for developing evidence-based guidelines to reduce the presumed increase in health care costs, risk of cesarean delivery for nulliparas, and overscheduling in labor and delivery.

IDENTIFYING A POPULATION-BASED SAMPLE OF WOMEN OF REPRODUCTIVE AGE FOR ENVIRONMENTAL STUDIES USING A COMMERCIAL TELEPHONE DIRECTORY

EPA Science Inventory

Environmental studies examining reproductive endpoints such as spontaneous abortion or fertility often rely on very select study groups (i.e., convenience samples, highly exposed, etc.) that cannot be easily generalized to the overall population. For exposures limited to a parti...

How College Students Conceptualize and Practice Responsible Drinking

ERIC Educational Resources Information Center

Barry, Adam E.; Goodson, Patricia

2011-01-01

Objective: This study sought to employ a mixed-methods approach to (a) qualitatively explore responsible drinking beliefs and behaviors among a sample of college students, and (b) quantitatively assess the prevalence of those behaviors. Participants: Convenience samples, drawn from currently enrolled students attending a large public university in…

Teachers' Perceptions of School Leaders' Empowering Behaviours and Psychological Empowerment: Evidence from a Singapore Sample

ERIC Educational Resources Information Center

Lee, Ai Noi; Nie, Youyan

2017-01-01

Using a convenience sample of 289 teachers in Singapore, this study examined: (1) whether there were significant differences between teachers' perceptions of principal's and immediate supervisor's empowering behaviours; and (2) teachers' perceptions of principal's and immediate supervisor's empowering behaviours in relation to teachers'…

EVALUATION OF SPERM CHROMATIN STRUCTURE ASSAY (SCSA REGISTERED TRADEMARK) IN HUMAN SPERM AFTER SIMULATED OVERNIGHT SHIPMENT

EPA Science Inventory

Home semen collection kits allow men to collect a sample at their convenience and send it via overnight mail to the laboratory. Benefits of this approach include facilitated sample collection from different geographic locations, minimized variability through analysis by a central...

Attitudes of Arab Americans toward Persons with Developmental Disabilities

ERIC Educational Resources Information Center

Zidan, Tarek

2016-01-01

This quantitative cross-sectional study examines the overall attitudes of a sample of Arab Americans toward persons with disabilities. A convenience sample of 372 Arab Americans was recruited from various not-for-profit Arab organizations within 30 States. Participants in the study completed an online self-administered (Qualtrics) survey that…

A Retrospective Look at Website Accessibility over Time

ERIC Educational Resources Information Center

Hackett, Stephanie; Parmanto, Bambang; Zeng, Xiaoming

2005-01-01

Websites were retrospectively analysed to study the effects that technological advances in web design have had on accessibility for persons with disabilities. A random sample of general websites and a convenience sample of US government websites were studied and compared for the years 1997-2002. Web accessibility barrier (WAB) and complexity…

Robotic voltammetry with carbon nanotube-based sensors: a superb blend for convenient high-quality antimicrobial trace analysis

PubMed Central

Theanponkrang, Somjai; Suginta, Wipa; Weingart, Helge; Winterhalter, Mathias; Schulte, Albert

2015-01-01

A new automated pharmacoanalytical technique for convenient quantification of redox-active antibiotics has been established by combining the benefits of a carbon nanotube (CNT) sensor modification with electrocatalytic activity for analyte detection with the merits of a robotic electrochemical device that is capable of sequential nonmanual sample measurements in 24-well microtiter plates. Norfloxacin (NFX) and ciprofloxacin (CFX), two standard fluoroquinolone antibiotics, were used in automated calibration measurements by differential pulse voltammetry (DPV) and accomplished were linear ranges of 1–10 μM and 2–100 μM for NFX and CFX, respectively. The lowest detectable levels were estimated to be 0.3±0.1 μM (n=7) for NFX and 1.6±0.1 μM (n=7) for CFX. In standard solutions or tablet samples of known content, both analytes could be quantified with the robotic DPV microtiter plate assay, with recoveries within ±4% of 100%. And recoveries were as good when NFX was evaluated in human serum samples with added NFX. The use of simple instrumentation, convenience in execution, and high effectiveness in analyte quantitation suggest the merger between automated microtiter plate voltammetry and CNT-supported electrochemical drug detection as a novel methodology for antibiotic testing in pharmaceutical and clinical research and quality control laboratories. PMID:25670899

Retirement Planning and Counseling: Issues and Challenges for Teachers in Public Schools in the Sekondi Circuit

ERIC Educational Resources Information Center

Wilson, Kwesi Nkum; Aggrey, Ellen Aba Munkua

2012-01-01

The purpose of the study was to explore retirement planning, challenges, and counseling among teachers of public schools in the Sekondi Circuit in the Western Region, Ghana. A sample of 50 teachers was selected through convenience sampling. Only teachers who expressed interest in participating in the study were sampled. The main instrument for…

Awareness and Perceptions of Food Safety Risks and Risk Management in Poultry Production and Slaughter: A Qualitative Study of Direct-Market Poultry Producers in Maryland

PubMed Central

Baron, Patrick; Frattaroli, Shannon

2016-01-01

The objective of this study was to document and understand the perceptions and opinions of small-scale poultry producers who market directly to consumers about microbial food safety risks in the poultry supply chain. Between January and November 2014, we conducted semi-structured, in-depth interviews with a convenience sample of 16 owner-operators of Maryland direct-market commercial poultry farms. Three overarching thematic categories emerged from these interviews that describe: 1) characteristics of Maryland direct-market poultry production and processing; 2) microbial food safety risk awareness and risk management in small-scale poultry production, slaughter and processing; and 3) motivations for prioritizing food safety in the statewide direct-market poultry supply chain. Key informants provided valuable insights on many topics relevant to evaluating microbial food safety in the Maryland direct-market poultry supply chain, including: direct-market poultry production and processing practices and models, perspectives on issues related to food safety risk management, perspectives on direct-market agriculture economics and marketing strategies, and ideas for how to enhance food safety at the direct-market level of the Maryland poultry supply chain. The findings have policy implications and provide insights into food safety in small-scale commercial poultry production, processing, distribution and retail. In addition, the findings will inform future food safety research on the small-scale US poultry supply chain. PMID:27341034

76 FR 59596 - Anchorage Regulations; Newport, RI

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-27

... up to three cruise ships simultaneously in anchorage ``D''. For the convenience and safety of... standards (e.g., specifications of materials, performance, design, or operation; test methods; sampling...

Prevalence of substandard and falsified artemisinin-based combination antimalarial medicines on Bioko Island, Equatorial Guinea

PubMed Central

Kaur, Harparkash; Allan, Elizabeth Louise; Mamadu, Ibrahim; Hall, Zoe; Green, Michael D; Swamidos, Isabel; Dwivedi, Prabha; Culzoni, Maria Julia; Fernandez, Facundo M; Garcia, Guillermo; Hergott, Dianna; Monti, Feliciano

2017-01-01

Introduction Poor-quality artemisinin-containing antimalarials (ACAs), including falsified and substandard formulations, pose serious health concerns in malaria endemic countries. They can harm patients, contribute to the rise in drug resistance and increase the public’s mistrust of health systems. Systematic assessment of drug quality is needed to gain knowledge on the prevalence of the problem, to provide Ministries of Health with evidence on which local regulators can take action. Methods We used three sampling approaches to purchase 677 ACAs from 278 outlets on Bioko Island, Equatorial Guinea as follows: convenience survey using mystery client (n=16 outlets, 31 samples), full island-wide survey using mystery client (n=174 outlets, 368 samples) and randomised survey using an overt sampling approach (n=88 outlets, 278 samples). The stated active pharmaceutical ingredients (SAPIs) were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories. Results Content analysis showed 91.0% of ACAs were of acceptable quality, 1.6% were substandard and 7.4% falsified. No degraded medicines were detected. The prevalence of medicines without the SAPIs was higher for ACAs purchased in the convenience survey compared with the estimates obtained using the full island-wide survey-mystery client and randomised-overt sampling approaches. Comparable results were obtained for full island survey-mystery client and randomised overt. However, the availability of purchased artesunate monotherapies differed substantially according to the sampling approach used (convenience, 45.2%; full island-wide survey-mystery client, 32.6%; random-overt sampling approach, 21.9%). Of concern is that 37.1% (n=62) of these were falsified. Conclusion Falsified ACAs were found on Bioko Island, with the prevalence ranging between 6.1% and 16.1%, depending on the sampling method used. These findings underscore the vital need for national authorities to track the scale of ineffective medicines that jeopardise treatment of life-threatening diseases and value of a representative sampling approach to obtain/measure the true prevalence of poor-quality medicines. PMID:29082025

RadVel: The Radial Velocity Modeling Toolkit

NASA Astrophysics Data System (ADS)

Fulton, Benjamin J.; Petigura, Erik A.; Blunt, Sarah; Sinukoff, Evan

2018-04-01

RadVel is an open-source Python package for modeling Keplerian orbits in radial velocity (RV) timeseries. RadVel provides a convenient framework to fit RVs using maximum a posteriori optimization and to compute robust confidence intervals by sampling the posterior probability density via Markov Chain Monte Carlo (MCMC). RadVel allows users to float or fix parameters, impose priors, and perform Bayesian model comparison. We have implemented real-time MCMC convergence tests to ensure adequate sampling of the posterior. RadVel can output a number of publication-quality plots and tables. Users may interface with RadVel through a convenient command-line interface or directly from Python. The code is object-oriented and thus naturally extensible. We encourage contributions from the community. Documentation is available at http://radvel.readthedocs.io.

Junk food seen at pediatric clinic visits: is it a problem?

PubMed

Frazier, Johnnie P; Land, Megan; Hsieh, Pei-Hsuan; Barratt, Michelle S

2014-04-01

To document the prevalence of junk foods seen at clinic visits. A cross-sectional 23-item survey of observed food items were completed by medical staff using a convenience sample of families from June 2, 2011 to March 2, 2012. The study was conducted in pediatric clinics affiliated with the University of Texas Medical School at Houston. A convenience sample consisting of 738 families with children from 4 months to 16 years old presenting for visits were included in the study. Children exclusively breast and formula fed was excluded. Junk food was observed 20.9% at the clinic visits. Junk food was often seen at clinic visits. There was a trend toward higher body mass index in patients whose families had junk food at the visit.

Screening and staging for non-small cell lung cancer by serum laser Raman spectroscopy.

PubMed

Wang, Hong; Zhang, Shaohong; Wan, Limei; Sun, Hong; Tan, Jie; Su, Qiucheng

2018-08-05

Lung cancer is the leading cause of cancer-related death worldwide. Current clinical screening methods to detect lung cancer are expensive and associated with many complications. Raman spectroscopy is a spectroscopic technique that offers a convenient method to gain molecular information about biological samples. In this study, we measured the serum Raman spectral intensity of healthy volunteers and patients with different stages of non-small cell lung cancer. The purpose of this study was to evaluate the application of serum laser Raman spectroscopy as a low cost alternative method in the screening and staging of non-small cell lung cancer (NSCLC). The Raman spectra of the sera of peripheral venous blood were measured with a LabRAM HR 800 confocal Micro Raman spectrometer for individuals from five groups including 14 healthy volunteers (control group), 23 patients with stage I NSCLC (stage I group), 24 patients with stage II NSCLC (stage II group), 19 patients with stage III NSCLC (stage III group), 11 patients with stage IV NSCLC (stage IV group). Each serum sample was measured 3 times at different spots and the average spectra represented the signal of Raman spectra in each case. The Raman spectrum signal data of the five groups were statistically analyzed by analysis of variance (ANOVA), principal component analysis (PCA), linear discriminant analysis (LDA), and cross-validation. Raman spectral intensity was sequentially reduced in serum samples from control group, stage I group, stage II group and stage III/IV group. The strongest peak intensity was observed in the control group, and the weakest one was found in the stage III/IV group at bands of 848 cm -1 , 999 cm -1 , 1152 cm -1 , 1446 cm -1 and 1658 cm -1 (P < 0.05). Linear discriminant analysis showed that the sensitivity to identify healthy people, stage I, stage II, and stage III/IV NSCLC was 86%, 65%, 75%, and 87%, respectively; the specificity was 95%, 94%, 88%, and 93%, respectively; and the overall accuracy rate was 92% (71/77). The laser Raman spectroscopy can effectively identify patients with stage I, stage II or stage III/IV Non-Small Cell Lung cancer using patient serum samples. Copyright © 2018 Elsevier B.V. All rights reserved.

Availability of convenience stores and adolescent alcohol use in Taiwan: a multi-level analysis of national surveys.

PubMed

Wang, Shi-Heng; Lin, I-Chin; Chen, Chuan-Yu; Chen, Duan-Rung; Chan, Ta-Chien; Chen, Wei J

2013-12-01

To examine the association between alcohol in school environments and adolescent alcohol use over the previous 6 months. A multi-level logistic regression analysis was performed of cross-sectional surveys conducted in 2004, 2005 and 2006. A total of 52 214 students aged 11-19 years from 387 middle or high schools were selected from a nationally representative, multi-stage, stratified probability sampling across Taiwan. Information on socio-demographic features and substance use experiences was collected using self-administered questionnaires. The alcohol in the environment was measured using the availability of convenience stores surrounding the schools. Using geographical information systems, the weighted numbers of convenience stores within 1 km, a 12-15-minute walk, of a school were calculated. The schools were later categorized into three subgroups via the tertile of nearby convenience stores. Considering the compositional characteristics, the availability of convenience stores was found to account for 1.5% of the school-level variance of youthful drinking. The odds ratios (95% confidence interval) of alcohol use over the previous 6 months among youth attending schools with medium and high availability were 1.04 (0.96-1.13) and 1.08 (1.00-1.17), respectively, with a P-value of 0.04 in the trend test. The greater availability of convenience stores near a school is associated with an increased risk of alcohol use among adolescents over the previous 6 months. © 2013 Society for the Study of Addiction.

Comparing two sampling methods to engage hard-to-reach communities in research priority setting.

PubMed

Valerio, Melissa A; Rodriguez, Natalia; Winkler, Paula; Lopez, Jaime; Dennison, Meagen; Liang, Yuanyuan; Turner, Barbara J

2016-10-28

Effective community-partnered and patient-centered outcomes research needs to address community priorities. However, optimal sampling methods to engage stakeholders from hard-to-reach, vulnerable communities to generate research priorities have not been identified. In two similar rural, largely Hispanic communities, a community advisory board guided recruitment of stakeholders affected by chronic pain using a different method in each community: 1) snowball sampling, a chain- referral method or 2) purposive sampling to recruit diverse stakeholders. In both communities, three groups of stakeholders attended a series of three facilitated meetings to orient, brainstorm, and prioritize ideas (9 meetings/community). Using mixed methods analysis, we compared stakeholder recruitment and retention as well as priorities from both communities' stakeholders on mean ratings of their ideas based on importance and feasibility for implementation in their community. Of 65 eligible stakeholders in one community recruited by snowball sampling, 55 (85 %) consented, 52 (95 %) attended the first meeting, and 36 (65 %) attended all 3 meetings. In the second community, the purposive sampling method was supplemented by convenience sampling to increase recruitment. Of 69 stakeholders recruited by this combined strategy, 62 (90 %) consented, 36 (58 %) attended the first meeting, and 26 (42 %) attended all 3 meetings. Snowball sampling recruited more Hispanics and disabled persons (all P < 0.05). Despite differing recruitment strategies, stakeholders from the two communities identified largely similar ideas for research, focusing on non-pharmacologic interventions for management of chronic pain. Ratings on importance and feasibility for community implementation differed only on the importance of massage services (P = 0.045) which was higher for the purposive/convenience sampling group and for city improvements/transportation services (P = 0.004) which was higher for the snowball sampling group. In each of the two similar hard-to-reach communities, a community advisory board partnered with researchers to implement a different sampling method to recruit stakeholders. The snowball sampling method achieved greater participation with more Hispanics but also more individuals with disabilities than a purposive-convenience sampling method. However, priorities for research on chronic pain from both stakeholder groups were similar. Although utilizing a snowball sampling method appears to be superior, further research is needed on implementation costs and resources.

SPME as a promising tool in translational medicine and drug discovery: From bench to bedside.

PubMed

Goryński, Krzysztof; Goryńska, Paulina; Górska, Agnieszka; Harężlak, Tomasz; Jaroch, Alina; Jaroch, Karol; Lendor, Sofia; Skobowiat, Cezary; Bojko, Barbara

2016-10-25

Solid phase microextraction (SPME) is a technology where a small amount of an extracting phase dispersed on a solid support is exposed to the sample for a well-defined period of time. The open-bed geometry and biocompatibility of the materials used for manufacturing of the devices makes it very convenient tool for direct extraction from complex biological matrices. The flexibility of the formats permits tailoring the method according the needs of the particular application. Number of studies concerning monitoring of drugs and their metabolites, analysis of metabolome of volatile as well as non-volatile compounds, determination of ligand-protein binding, permeability and compound toxicity was already reported. All these applications were performed in different matrices including biological fluids and tissues, cell cultures, and in living animals. The low invasiveness of in vivo SPME, ability of using very small sample volumes and analysis of cell cultures permits to address the rule of 3R, which is currently acknowledged ethical standard in R&D labs. In the current review systematic evaluation of the applicability of SPME to studies required to be conduct at different stages of drug discovery and development and translational medicine is presented. The advantages and challenges are discussed based on the examples directly showing given experimental design or on the studies, which could be translated to the models routinely used in drug development process. Copyright © 2016 Elsevier B.V. All rights reserved.

DNA-mediated strand displacement facilitates sensitive electronic detection of antibodies in human serums.

PubMed

Dou, Baoting; Yang, Jianmei; Shi, Kai; Yuan, Ruo; Xiang, Yun

2016-09-15

We describe here the development of a sensitive and convenient electronic sensor for the detection of antibodies in human serums. The sensor is constructed by self-assembly formation of a mixed monolayer containing the small molecule epitope conjugated double stranded DNA probes on gold electrode. The target antibody binds the epitope on the dsDNA probe and lowers the melting temperature of the duplex, which facilitates the displacement of the antibody-linked strand of the duplex probe by an invading methylene blue-tagged single stranded DNA (MB-ssDNA) through the strand displacement reaction and leads to the capture of many MB-ssDNA on the sensor surface. Subsequent electrochemical oxidation of the methylene blue labels results in amplified current response for sensitive monitoring of the antibodies. The antibody assay conditions are optimized and the sensor exhibits a linear range between 1.0 and 25.0nM with a detection limit of 0.67nM for the target antibody. The sensor is also selective and can be employed to detect the target antibodies in human serum samples. With the advantages of using small molecule epitope as the antibody recognition element over traditional antigen, the versatile manipulability of the DNA probes and the unique properties of the electrochemical transduction technique, the developed sensor thus hold great potential for simple and sensitive detection of different antibodies and other proteins in real samples. Copyright © 2016 Elsevier B.V. All rights reserved.

A generic implementation of replica exchange with solute tempering (REST2) algorithm in NAMD for complex biophysical simulations

NASA Astrophysics Data System (ADS)

Jo, Sunhwan; Jiang, Wei

2015-12-01

Replica Exchange with Solute Tempering (REST2) is a powerful sampling enhancement algorithm of molecular dynamics (MD) in that it needs significantly smaller number of replicas but achieves higher sampling efficiency relative to standard temperature exchange algorithm. In this paper, we extend the applicability of REST2 for quantitative biophysical simulations through a robust and generic implementation in greatly scalable MD software NAMD. The rescaling procedure of force field parameters controlling REST2 "hot region" is implemented into NAMD at the source code level. A user can conveniently select hot region through VMD and write the selection information into a PDB file. The rescaling keyword/parameter is written in NAMD Tcl script interface that enables an on-the-fly simulation parameter change. Our implementation of REST2 is within communication-enabled Tcl script built on top of Charm++, thus communication overhead of an exchange attempt is vanishingly small. Such a generic implementation facilitates seamless cooperation between REST2 and other modules of NAMD to provide enhanced sampling for complex biomolecular simulations. Three challenging applications including native REST2 simulation for peptide folding-unfolding transition, free energy perturbation/REST2 for absolute binding affinity of protein-ligand complex and umbrella sampling/REST2 Hamiltonian exchange for free energy landscape calculation were carried out on IBM Blue Gene/Q supercomputer to demonstrate efficacy of REST2 based on the present implementation.

Sub-grouping patients with non-specific low back pain based on cluster analysis of discriminatory clinical items.

PubMed

Billis, Evdokia; McCarthy, Christopher J; Roberts, Chris; Gliatis, John; Papandreou, Maria; Gioftsos, George; Oldham, Jacqueline A

2013-02-01

To identify potential subgroups amongst patients with non-specific low back pain based on a consensus list of potentially discriminatory examination items. Exploratory study. A convenience sample of 106 patients with non-specific low back pain (43 males, 63 females, mean age 36 years, standard deviation 15.9 years) and 7 physiotherapists. Based on 3 focus groups and a two-round Delphi involving 23 health professionals and a random stratified sample of 150 physiotherapists, respectively, a comprehensive examination list comprising the most "discriminatory" items was compiled. Following reliability analysis, the most reliable clinical items were assessed with a sample of patients with non-specific low back pain. K-means cluster analysis was conducted for 2-, 3- and 4-cluster options to explore for meaningful homogenous subgroups. The most clinically meaningful cluster was a two-subgroup option, comprising a small group (n = 24) with more severe clinical presentation (i.e. more widespread pain, functional and sleeping problems, other symptoms, increased investigations undertaken, more severe clinical signs, etc.) and a larger less dysfunctional group (n = 80). A number of potentially discriminatory clinical items were identified by health professionals and sub-classified, based on a sample of patients with non-specific low back pain, into two subgroups. However, further work is needed to validate this classification process.

Microplate based optical biosensor for L-Dopa using tyrosinase from Amorphophallus campanulatus.

PubMed

Saini, Amardeep Singh; Kumar, Jitendra; Melo, Jose Savio

2014-11-07

Developing a biosensor which is capable of simultaneously monitoring l-Dopa levels in multiple samples besides requiring small reaction volume is of great value. The present study describes the detection of l-Dopa using tyrosinase enzyme extracted from Amorphophallus campanulatus and immobilized on the surface of the microplate wells. Among the different approaches used for immobilizing tyrosinase onto the microplate wells, glutaraldehyde treatment was found to be most effective. Besides enzyme activity, ESEM-EDS (environmental scanning electron microscope-energy dispersive system) and Atomic Force Microscopy (AFM) were also carried out to confirm the immobilization of tyrosinase enzyme onto the microplate well surface. This immobilized biocomponent was then integrated with an optical transducer for l-Dopa detection and it showed good reproducibility. The sensing property of the system was studied by measuring the initial rate of dopachrome formation at 475 nm. The calibration plot gave a linear range of detection from 10-1000 μM and the detection limit was calculated to be 3 μM. The immobilized biocomponent was stable for 41 days and was reused up to nine times. Spiked samples (blood plasma) were also analyzed using this biocomponent. This microplate based biosensor thus provides a convenient system for detection of multiple samples in a single run. Copyright © 2014 Elsevier B.V. All rights reserved.

Semiautomatic Segmentation of Glioma on Mobile Devices.

PubMed

Wu, Ya-Ping; Lin, Yu-Song; Wu, Wei-Guo; Yang, Cong; Gu, Jian-Qin; Bai, Yan; Wang, Mei-Yun

2017-01-01

Brain tumor segmentation is the first and the most critical step in clinical applications of radiomics. However, segmenting brain images by radiologists is labor intense and prone to inter- and intraobserver variability. Stable and reproducible brain image segmentation algorithms are thus important for successful tumor detection in radiomics. In this paper, we propose a supervised brain image segmentation method, especially for magnetic resonance (MR) brain images with glioma. This paper uses hard edge multiplicative intrinsic component optimization to preprocess glioma medical image on the server side, and then, the doctors could supervise the segmentation process on mobile devices in their convenient time. Since the preprocessed images have the same brightness for the same tissue voxels, they have small data size (typically 1/10 of the original image size) and simple structure of 4 types of intensity value. This observation thus allows follow-up steps to be processed on mobile devices with low bandwidth and limited computing performance. Experiments conducted on 1935 brain slices from 129 patients show that more than 30% of the sample can reach 90% similarity; over 60% of the samples can reach 85% similarity, and more than 80% of the sample could reach 75% similarity. The comparisons with other segmentation methods also demonstrate both efficiency and stability of the proposed approach.

Hierarchical spatial capture-recapture models: Modeling population density from stratified populations

USGS Publications Warehouse

Royle, J. Andrew; Converse, Sarah J.

2014-01-01

Capture–recapture studies are often conducted on populations that are stratified by space, time or other factors. In this paper, we develop a Bayesian spatial capture–recapture (SCR) modelling framework for stratified populations – when sampling occurs within multiple distinct spatial and temporal strata.We describe a hierarchical model that integrates distinct models for both the spatial encounter history data from capture–recapture sampling, and also for modelling variation in density among strata. We use an implementation of data augmentation to parameterize the model in terms of a latent categorical stratum or group membership variable, which provides a convenient implementation in popular BUGS software packages.We provide an example application to an experimental study involving small-mammal sampling on multiple trapping grids over multiple years, where the main interest is in modelling a treatment effect on population density among the trapping grids.Many capture–recapture studies involve some aspect of spatial or temporal replication that requires some attention to modelling variation among groups or strata. We propose a hierarchical model that allows explicit modelling of group or strata effects. Because the model is formulated for individual encounter histories and is easily implemented in the BUGS language and other free software, it also provides a general framework for modelling individual effects, such as are present in SCR models.

Vendor compliance with Ontario's tobacco point of sale legislation.

PubMed

Dubray, Jolene M; Schwartz, Robert M; Garcia, John M; Bondy, Susan J; Victor, J Charles

2009-01-01

On May 31, 2006, Ontario joined a small group of international jurisdictions to implement legislative restrictions on tobacco point of sale promotions. This study compares the presence of point of sale promotions in the retail tobacco environment from three surveys: one prior to and two following implementation of the legislation. Approximately 1,575 tobacco vendors were randomly selected for each survey. Each regionally-stratified sample included equal numbers of tobacco vendors categorized into four trade classes: chain convenience, independent convenience and discount, gas stations, and grocery. Data regarding the six restricted point of sale promotions were collected using standardized protocols and inspection forms. Weighted estimates and 95% confidence intervals were produced at the provincial, regional and vendor trade class level using the bootstrap method for estimating variance. At baseline, the proportion of tobacco vendors who did not engage in each of the six restricted point of sale promotions ranged from 41% to 88%. Within four months following implementation of the legislation, compliance with each of the six restricted point of sale promotions exceeded 95%. Similar levels of compliance were observed one year later. Grocery stores had the fewest point of sale promotions displayed at baseline. Compliance rates did not differ across vendor trade classes at either follow-up survey. Point of sale promotions did not differ across regions in any of the three surveys. Within a short period of time, a high level of compliance with six restricted point of sale promotions was achieved.

Field-controlled structures in ferromagnetic cholesteric liquid crystals.

PubMed

Medle Rupnik, Peter; Lisjak, Darja; Čopič, Martin; Čopar, Simon; Mertelj, Alenka

2017-10-01

One of the advantages of anisotropic soft materials is that their structures and, consequently, their properties can be controlled by moderate external fields. Whereas the control of materials with uniform orientational order is straightforward, manipulation of systems with complex orientational order is challenging. We show that a variety of structures of an interesting liquid material, which combine chiral orientational order with ferromagnetic one, can be controlled by a combination of small magnetic and electric fields. In the suspensions of magnetic nanoplatelets in chiral nematic liquid crystals, the platelet's magnetic moments orient along the orientation of the liquid crystal and, consequently, the material exhibits linear response to small magnetic fields. In the absence of external fields, orientations of the liquid crystal and magnetization have wound structure, which can be either homogeneously helical, disordered, or ordered in complex patterns, depending on the boundary condition at the surfaces and the history of the sample. We demonstrate that by using different combinations of small magnetic and electric fields, it is possible to control reversibly the formation of the structures in a layer of the material. In such a way, different periodic structures can be explored and some of them may be suitable for photonic applications. The material is also a convenient model system to study chiral magnetic structures, because it is a unique liquid analog of a solid helimagnet.

Understanding the motives for food choice in Western Balkan Countries.

PubMed

Milošević, Jasna; Žeželj, Iris; Gorton, Matthew; Barjolle, Dominique

2012-02-01

Substantial empirical evidence exists regarding the importance of different factors underlying food choice in Western Europe. However, research results on eating habits and food choice in the Western Balkan Countries (WBCs) remain scarce. A Food Choice Questionnaire (FCQ), an instrument that measures the reported importance of nine factors underlying food choice, was administered to a representative sample of 3085 adult respondents in six WBCs. The most important factors reported are sensory appeal, purchase convenience, and health and natural content; the least important are ethical concern and familiarity. The ranking of food choice motives across WBCs was strikingly similar. Factor analysis revealed eight factors compared to nine in the original FCQ model: health and natural content scales loaded onto one factor as did familiarity and ethical concern; the convenience scale items generated two factors, one related to purchase convenience and the other to preparation convenience. Groups of consumers with similar motivational profiles were identified using cluster analysis. Each cluster has distinct food purchasing behavior and socio-economic characteristics, for which appropriate public health communication messages can be drawn. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Analysis of Fourth Grade Primary Students' Reader Self-Perceptions in Terms of Gender and Preschool Educational Background

ERIC Educational Resources Information Center

Sagirli, Muhittin; Okur, Burçin

2017-01-01

The aim of this study was to analyse perceptions of fourth grade primary school students on their reading ability. In study, screening model was used as a quantitative research method. The sample of this research was selected by convenience sampling. The sample consisted of 556 fourth grade students who received education in 8 public schools in…

Examining Work and Family Conflict among Female Bankers in Accra Metropolis, Ghana

ERIC Educational Resources Information Center

Kissi-Abrokwah, Bernard; Andoh-Robertson, Theophilus; Tutu-Danquah, Cecilia; Agbesi, Catherine Selorm

2015-01-01

This study investigated the effects and solutions of work and family conflict among female bankers in Accra Metropolis. Using triangulatory mixed method design, a structured questionnaire was randomly administered to 300 female bankers and 15 female Bankers who were interviewed were also sampled by using convenient sampling technique. The…

Investigating ESL Students' Academic Performance in Tenses

ERIC Educational Resources Information Center

Javed, Muhammad; Ahmad, Atezaz

2013-01-01

The present study intends to assess the ESL students' performance in tenses at secondary school level. Grade 10 students were the target population of the study. A sample of 396 students (255 male and 141 female) was selected through convenience sampling technique from the District of Bahawalnagar, Pakistan. A test focusing on five different types…

40 CFR 53.63 - Test procedure: Wind tunnel inlet aspiration test.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the sampler inlet opening centered in the sampling zone. To meet the maximum blockage limit of § 53.62(c)(1) or for convenience, part of the test sampler may be positioned external to the wind tunnel... = reference method sampler volumetric flow rate; and t = sampling time. (iii) Remove the reference method...

The Relationship between Childhood Sexual Abuse and Sexual Dysfunction in Jamaican Adults

ERIC Educational Resources Information Center

Swaby, Antoneal N.; Morgan, Kai A. D.

2009-01-01

This study examined the associations between early traumatic sexualization and later sexual dysfunction in a sample of 100 Jamaican adults while identifying the linkages between age, frequency of abuse, and gender on sexual functioning. Participants were selected via purposive and convenience sampling and divided equally into comparison and…

Glycemic Control in a Clinic-Based Sample of Diabetics in M'Bour Senegal

ERIC Educational Resources Information Center

BeLue, Rhonda; Ndiaye, Khadidiatou; NDao, Fatou; Ba, Fatou Niass Niang; Diaw, Mor

2016-01-01

Background: Sub-Saharan Africa (SSA) including Senegal is faced with a significant and increasing burden of type 2 diabetes. However, little information is available about diabetes management among Senegalese diabetics. Purpose: The current study aims to describe the level of glycemic control among a convenience sample of diabetics who receive…

Alcohol Policies and Free to be Foolish: An Analysis of College Students.

ERIC Educational Resources Information Center

Reis, Janet; Chamberlain, Elizabeth Ann

1994-01-01

Results of a convenience sample of predominately white undergraduate students from a large public university in the Midwest. Students were surveyed with regard to their views about alcohol consumption. The sample was divided between 239 libertarians and 192 supporters of collective responsibility as defined by their positions on alcohol…

Suicidal Ideation and Attempts among Sexual Minority Youths Receiving Social Services

ERIC Educational Resources Information Center

Walls, Eugene N.; Freedenthal, Stacey; Wisneski, Hope

2008-01-01

The increased risk of suicidal ideation and attempts among sexual minority youths have been documented in studies using both convenience samples and representative community samples. However, as most youths do not access social services, these studies do not necessarily represent the sexual minority youths that community-based social workers may…

The Prevalence of Speech Disorders among University Students in Jordan

ERIC Educational Resources Information Center

Alaraifi, Jehad Ahmad; Amayreh, Mousa Mohammad; Saleh, Mohammad Yusef

2014-01-01

Problem: There are no available studies on the prevalence, and distribution of speech disorders among Arabic speaking undergraduate students in Jordan. Method: A convenience sample of 400 undergraduate students at the University of Jordan was screened for speech disorders. Two spontaneous speech samples and an oral reading of a passage were…

Likelihood of Condom Use When Sexually Transmitted Diseases Are Suspected: Results from a Clinic Sample

ERIC Educational Resources Information Center

Crosby, Richard A.; Milhausen, Robin R.; Graham, Cynthia A.; Yarber, William L.; Sanders, Stephanie A.; Charnigo, Richard; Shrier, Lydia A.

2014-01-01

Objective: To determine the event-level associations between perceived risk of sexually transmitted disease (STD) acquisition/transmission and condom use during penile-vaginal intercourse (PVI) among STD clinic attendees. Method: A convenience sample (N = 622) completed daily electronic assessments. Two questions were proxies of perceived risk:…

In-situ monitoring of flow-permeable surface area of high explosive powder using small sample masses

DOE PAGES

Maiti, Amitesh; Han, Yong; Zaka, Fowzia; ...

2015-02-17

To ensure good performance of high explosive devices over long periods of time, initiating powders need to maintain their specific surface area within allowed margins during the entire duration of deployment. A common diagnostic used in this context is the Fisher sub-sieve surface area (FSSA). Furthermore, commercial permeametry instruments measuring the FSSA requires the utilization of a sample mass equal to the crystal density of the sample material, an amount that is often one or two orders of magnitude larger than the typical masses found in standard detonator applications. Here we develop a customization of the standard device that canmore » utilize just tens of milligram samples, and with simple calibration yield FSSA values at ac curacy levels comparable to the standard apparatus. This necessitated a newly designed sample holder, made from a material of low coefficient of thermal expansion, which is conveniently transferred between an aging chamber and a re-designed permeametry tube. This improves the fidelity of accelerated aging studies by allowing measurement on the same physical sample at various time - instants during the aging process, and by obviating the need for a potentially FSSA-altering powder re-compaction step. We used the customized apparatus to monitor the FSSA evolution of a number of undoped and homolog-doped PETN powder samples that were subjected to artificial aging for several months at elevated temperatures. These results, in conjunction with an Arrhenius-based aging model were used to assess powder-coarsening - rates under long-term storage.« less

A novel membrane inlet mass spectrometer method to measure ¹⁵NH4₄⁺ for isotope-enrichment experiments in aquatic ecosystems.

PubMed

Yin, Guoyu; Hou, Lijun; Liu, Min; Liu, Zhanfei; Gardner, Wayne S

2014-08-19

Nitrogen (N) pollution in aquatic ecosystems has attracted much attention over the past decades, but the dynamics of this bioreactive element are difficult to measure in aquatic oxygen-transition environments. Nitrogen-transformation experiments often require measurement of (15)N-ammonium ((15)NH4(+)) ratios in small-volume (15)N-enriched samples. Published methods to determine N isotope ratios of dissolved ammonium require large samples and/or costly equipment and effort. We present a novel ("OX/MIMS") method to determine N isotope ratios for (15)NH4(+) in experimental waters previously enriched with (15)N compounds. Dissolved reduced (15)N (dominated by (15)NH4(+)) is oxidized with hypobromite iodine to nitrogen gas ((29)N2 and/or (30)N2) and analyzed by membrane inlet mass spectrometry (MIMS) to quantify (15)NH4(+) concentrations. The N isotope ratios, obtained by comparing the (15)NH4(+) to total ammonium (via autoanalyzer) concentrations, are compared to the ratios of prepared standards. The OX/MIMS method requires only small sample volumes of water (ca. 12 mL) or sediment slurries and is rapid, convenient, accurate, and precise (R(2) = 0.9994, p < 0.0001) over a range of salinities and (15)N/(14)N ratios. It can provide data needed to quantify rates of ammonium regeneration, potential ammonium uptake, and dissimilatory nitrate reduction to ammonium (DNRA). Isotope ratio results agreed closely (R = 0.998, P = 0.001) with those determined independently by isotope ratio mass spectrometry for DNRA measurements or by ammonium isotope retention time shift liquid chromatography for water-column N-cycling experiments. Application of OX/MIMS should simplify experimental approaches and improve understanding of N-cycling rates and fate in a variety of freshwater and marine environments.

Title: Efficacy of chlorine dioxide gas to decontaminate fresh produce used for in-store and vendor juicing operations

USDA-ARS?s Scientific Manuscript database

Introduction: Unpasteurized juices are increasingly popular as consumers aim to find convenient, healthy options. Contamination of produce with pathogens such as Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes poses a risk. In-store treatment of small batches of mixed types of fresh...

Comparing the Readability of Text Displays on Paper, E-Book Readers, and Small Screen Devices

ERIC Educational Resources Information Center

Baker, Rebecca Dawn

2010-01-01

Science fiction has long promised the digitalization of books. Characters in films and television routinely check their palm-sized (or smaller) electronic displays for fast-scrolling information. However, this very technology, increasingly prevalent in today's world, has not been embraced universally. While the convenience of pocket-sized…

76 FR 2923 - Agency Information Collection Activities: Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-18

... search for the records sought. As a convenience, the form will allow researchers to provide credit card information to authorize billing and expedited mailing of the copies. You can also use Order Online! ( http... of information on respondents, including the use of information technology; and (e) whether small...

Reno: Your Best Bet

ERIC Educational Resources Information Center

Aas, Anne

2007-01-01

This article features Reno located in Nevada. Beyond the glamour and glitz of the casinos, Reno has much to offer visiting tourists. It claims to be "The Biggest Little City in the World," an apt name because, while Reno has the amenities of a larger city, it also offers the friendliness and convenience of a small town. Reno offers…

Demonstrating Microscale Gas Reactions Using Disposable Plastic Syringes

ERIC Educational Resources Information Center

Goodwin, Alan

2011-01-01

This article provides an example of a teacher's learning, since the author only became aware of the microscale technique described very late in his professional career. The technique provides a convenient method of preparing and manipulating gases on a very small scale and a relatively safe means of demonstrating reactions that would be very…

Book Review: Stars (Copyright 1985, Golden Press; New York)

NASA Astrophysics Data System (ADS)

Marigza, R. N., Jr.

2009-06-01

Stars is a part of the Golden Guides collection produced by Golden Press. It is a small 160 page paperback guide to the constellations, the sun, the moon, planets, and other celestial bodies. The book is convenient to carry along wherever you go, making it an easy to access reference material.

Real-Time Computer Graphics Simulation of Blockplay in Early Childhood

ERIC Educational Resources Information Center

Albin-Clark, A.; Howard, T. L. J.; Anderson, B.

2011-01-01

Observation of young children is commonplace in educational settings. For trainee practitioners however, gaining access at convenient times can be difficult. Even then, small snapshots of observable activity can only ever be captured. We describe the design and development of a cross-platform software application which can be used to support…

Evaluation of the adequacy of the consume-by date of rice balls sold at convenience stores.

PubMed

Sato, Jun; Yokokawa, Kana

2014-01-01

The adequacy of the consume-by date was validated for rice balls sold at convenience stores (CVSs),taking into account the process of distribution. The results indicated that the increase in the viable cell counts differed significantly depending on the type of rice balls and the storage temperature. At 19 h after delivery, Staphylococcus spp. were detected in 4 samples (26.7%) of the Tunamayo samples of Company A and in the majority of the Plum samples of Company B. Results showed there was a strong correlation between the elapsed time after delivery and the viable cell counts for all samples except for the Plum samples of Company B. The regression equations varied for the different types of rice balls and the different storage temperatures. Using the obtained regression equations and assuming a safety factor of 0.7, the appropriate consume-by date was determined to be 11 h for the Tunamayo and 38 h for the Plum of Company A, and 21 h for the Tunamayo of Company B. Among 14 strains of isolated Gram-negative bacteria, 11 strains (78.6%) belonged to the genus Serratia.

Monitoring the chemical production of citrus-derived bioactive 5-demethylnobiletin using surface enhanced Raman spectroscopy

PubMed Central

Zheng, Jinkai; Fang, Xiang; Cao, Yong; Xiao, Hang; He, Lili

2013-01-01

To develop an accurate and convenient method for monitoring the production of citrus-derived bioactive 5-demethylnobiletin from demethylation reaction of nobiletin, we compared surface enhanced Raman spectroscopy (SERS) methods with a conventional HPLC method. Our results show that both the substrate-based and solution-based SERS methods correlated with HPLC method very well. The solution method produced lower root mean square error of calibration and higher correlation coefficient than the substrate method. The solution method utilized an ‘affinity chromatography’-like procedure to separate the reactant nobiletin from the product 5-demthylnobiletin based on their different binding affinity to the silver dendrites. The substrate method was found simpler and faster to collect the SERS ‘fingerprint’ spectra of the samples as no incubation between samples and silver was needed and only trace amount of samples were required. Our results demonstrated that the SERS methods were superior to HPLC method in conveniently and rapidly characterizing and quantifying 5-demethylnobiletin production. PMID:23885986

Nutrition labeling and value size pricing at fast-food restaurants: a consumer perspective.

PubMed

O'Dougherty, Maureen; Harnack, Lisa J; French, Simone A; Story, Mary; Oakes, J Michael; Jeffery, Robert W

2006-01-01

This pilot study examined nutrition-related attitudes that may affect food choices at fast-food restaurants, including consumer attitudes toward nutrition labeling of fast foods and elimination of value size pricing. A convenience sample of 79 fast-food restaurant patrons aged 16 and above (78.5% white, 55% female, mean age 41.2 [17.1]) selected meals from fast-food restaurant menus that varied as to whether nutrition information was provided and value pricing included and completed a survey and interview on nutrition-related attitudes. Only 57.9% of participants rated nutrition as important when buying fast food. Almost two thirds (62%) supported a law requiring nutrition labeling on restaurant menus. One third (34%) supported a law requiring restaurants to offer lower prices on smaller instead of bigger-sized portions. This convenience sample of fast-food patrons supported nutrition labels on menus. More research is needed with larger samples on whether point-of-purchase nutrition labeling at fast-food restaurants raises perceived importance of nutrition when eating out.

78 FR 42079 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-15

... a three- year approval to continue the ERSG project. The ongoing evaluation employs a quasi-experimental/non-randomized design in which a convenience sample of participants in schools receiving universal...

19 CFR 151.29 - Expense of unlading and handling.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Molasses § 151.29 Expense of unlading and handling. No expense incidental to the unlading, transporting, or handling of sugar, sirup, or molasses for convenient weighing, gaging, measuring, sampling, or marking...

19 CFR 151.29 - Expense of unlading and handling.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Molasses § 151.29 Expense of unlading and handling. No expense incidental to the unlading, transporting, or handling of sugar, sirup, or molasses for convenient weighing, gaging, measuring, sampling, or marking...

Associations with dental caries experience among a convenience sample of Aboriginal Australian adults.

PubMed

Amarasena, N; Kapellas, K; Skilton, M R; Maple-Brown, L J; Brown, A; O'Dea, K; Celermajer, D S; Jamieson, L M

2015-12-01

Few studies have examined dental caries experience in Aboriginal adults. The objectives of this study were to describe the dental caries experience of some Aboriginal Australian adults residing in the Northern Territory, and to determine associations with dental caries experience. A convenience sample of Aboriginal adults from Australia's Northern Territory was dentally examined. Self-reported oral health information was collected through a questionnaire. Data were available for 312 participants. The per cent of untreated decayed teeth (per cent DT >0) was 77.9 (95% CI 73.0 to 82.1), the mean DT was 3.0 (95% CI 2.6 to 3.4), the prevalence of any caries experience (the per cent DMFT >0) was 95.5 (95% CI 92.6 to 97.3) and the mean DMFT was 9.7 (95% CI 8.9 to 10.5). In multivariable analyses, unemployment and not brushing teeth the previous day were associated with the per cent DT >0. Problem-based dental attendance was associated with both the mean DT and the per cent DMFT >0. Older age, residing in the capital city, being non-incarcerated, last visiting a dentist <1 year ago and problem-based dental attendance were associated with the mean DMFT. Dental caries experience among this convenience sample of Aboriginal Australian adults was very high. Most factors associated with dental caries were social determinants or dental service access-related. © 2015 Australian Dental Association.

Feasibility of corona discharge ion mobility spectrometry for direct analysis of samples extracted by dispersive liquid-liquid microextraction.

PubMed

Jafari, Mohammad T; Riahi, Farhad

2014-05-23

The capability of corona discharge ionization ion mobility spectrometry (CD-IMS) for direct analysis of the samples extracted by dispersive liquid-liquid microextraction (DLLME) was investigated and evaluated, for the first time. To that end, an appropriate new injection port was designed and constructed, resulting in possibility of direct injection of the known sample volume, without tedious sample preparation steps (e.g. derivatization, solvent evaporation, and re-solving in another solvent…). Malathion as a test compound was extracted from different matrices by a rapid and convenient DLLME method. The positive ion mobility spectra of the extracted malathion were obtained after direct injection of carbon tetrachloride or methanol solutions. The analyte responses were compared and the statistical results revealed the feasibility of direct analysis of the extracted samples in carbon tetrachloride, resulting in a convenient methodology. The coupled method of DLLME-CD-IMS was exhaustively validated in terms of sensitivity, dynamic range, recovery, and enrichment factor. Finally, various real samples of apple, river and underground water were analyzed, all verifying the feasibility and success of the proposed method for the easy extraction of the analyte using DLLME separation before the direct analysis by CD-IMS. Copyright © 2014 Elsevier B.V. All rights reserved.

Compact fluorescent lights and the impact of convenience and knowledge on household recycling rates.

PubMed

Wagner, Travis P

2011-06-01

Increased energy costs, social marketing campaigns, public subsidies, and reduced retail prices have dramatically increased the number of compact fluorescent lights (CFLs) installed worldwide. CFLs provide many benefits, but they contain a very small amount of mercury. Given the billions of CFLs in use worldwide, they represent a significant source of mercury unless CFLs are recycled and the mercury recovered in an environmentally sound manner. In the state of Maine (northeast United States), despite mandated recycling of CFLs and availability of free CFL recycling, the household CFL recycling rate is very low. A study was undertaken to identify the primary factors responsible for low recycling. The first step was to survey householders who use CFLs. The 520 survey responses indicated that insufficient knowledge regarding recycling and inconvenience of the collection system are the two primary factors for the low recycling rate. To validate these findings, the second step was an examination of the current collection system to assess (a) the knowledge requirements necessary for recycling and (b) the convenience of the collection system. The results of this examination validated that knowledge requirements were excessively difficult to fulfill and the collection system is not sufficiently convenient. Based on these results, waste managers should focus on increasing convenience and simplifying access to information when designing or improving household collection and recycling of CFLs. Copyright © 2011 Elsevier Ltd. All rights reserved.

29 CFR Appendix E to Subpart L of... - Test Methods for Protective Clothing

Code of Federal Regulations, 2012 CFR

2012-07-01

... strength of the specimen shall be the average of the five highest peak loads of resistance registered for 3... convenience. (2) Test method for determining the strength of cloth by tearing: Trapezoid Method. A. Test... directions shall be tested from each sample unit. (ii) The tearing strength of the sample unit shall be the...

29 CFR Appendix E to Subpart L of... - Test Methods for Protective Clothing

Code of Federal Regulations, 2014 CFR

2014-07-01

... strength of the specimen shall be the average of the five highest peak loads of resistance registered for 3... convenience. (2) Test method for determining the strength of cloth by tearing: Trapezoid Method. A. Test... directions shall be tested from each sample unit. (ii) The tearing strength of the sample unit shall be the...

The Scope of Assistive Technology in Learning Process of Students with Blindness

ERIC Educational Resources Information Center

Saleem, Saira; Sajjad, Shahida

2016-01-01

This study was carried out to investigate the scope of assistive technology in learning process of students with blindness. The sample of this study included 56 students with blindness between the ages of 11-22 years from secondary level of education. These students were selected through convenient sampling from five special schools located in…

Predicting Academic Success and Psychological Wellness in a Sample of Canadian Undergraduate Students

ERIC Educational Resources Information Center

Chow, Henry P. H.

2010-01-01

Introduction: University students need to cope with a complex new life role and to achieve academic success. This article explores the academic performance and psychological well-being among university students in a western Canadian city. Method: Using a convenience sample, a total of 501 undergraduate students in Regina, Saskatchewan took part in…

A Study on Primary and Secondary School Students' Misconceptions about Greenhouse Effect (Erzurum Sampling)

ERIC Educational Resources Information Center

Gul, Seyda; Yesilyurt, Selami

2011-01-01

The aim of this study is to determine what level of primary and secondary school students' misconceptions related to greenhouse effect is. Study group consists of totally 280 students attended to totally 8 primary and secondary schools (4 primary school, 4 secondary school) which were determined with convenient sampling method from center of…

Gas chromatography of volatile organic compounds

NASA Technical Reports Server (NTRS)

Zlatkis, A.

1973-01-01

System has been used for problems such as analysis of volatile metabolities in human blood and urine, analysis of air pollutants, and in tobacco smoke chemistry. Since adsorbent is reusable after porper reconditioning, method is both convenient and economical. System could be used for large scale on-site sampling programs in which sample is shipped to central location for analysis.

ELT Research in Turkey: A Content Analysis of Selected Features of Published Articles

ERIC Educational Resources Information Center

Yagiz, Oktay; Aydin, Burcu; Akdemir, Ahmet Selçuk

2016-01-01

This study reviews a selected sample of 274 research articles on ELT, published between 2005 and 2015 in Turkish contexts. In the study, 15 journals in ULAKBIM database and articles from national and international journals accessed according to convenience sampling method were surveyed and relevant articles were obtained. A content analysis was…

Preschool Education and Primary School Pre-Service Teachers' Perceptions about Classroom Management: A Metaphorical Analysis

ERIC Educational Resources Information Center

Uysal, Hatice; Burçak, Firdevs; Tepetas, Gülüzar Sule; Akman, Berrin

2014-01-01

The aim of the research was to determine the perceptions of preschool and primary school teachers about classroom management by means of metaphors. The sample which selected by the use of convenience sampling techniques was drawn from preschool and primary school undergraduate students who had taken the "Classroom Management" course in…

Learner Characteristics and Writing Performance in a Community College English as a Second Language Course: Some Unexpected Findings

ERIC Educational Resources Information Center

Lambert, Olga D.

2015-01-01

This study investigates the relationships between individual learner characteristics and gain in writing performance as measured by a standardized writing assessment in a sample of community college academic English as a Second Language (ESL) students in the United States. The ethnically and linguistically diverse convenience sample included 76…

The Tension of Elite "vs". Massified Higher Education Systems: How Prospective Students Perceive Public and Private Universities in Kenya

ERIC Educational Resources Information Center

Oketch, Moses O.

2009-01-01

This article examines how recent changes, leading to a diversified supply in Kenya's university education system, is reflected in prospective students' aspirations, perceptions and preferences to undertake university education. The results, based on a combination of a convenience and snowball sampling of settings, within which random samples of…

Bacterial contamination of the hands of food handlers as indicator of hand washing efficacy in some convenient food industries in South Africa.

PubMed

Aa, Lambrechts; Is, Human; Jh, Doughari; Jfr, Lues

2014-07-01

Hands of ready-to-eat food service employees have been shown to be vectors in the spread of foodborne disease, mainly because of poor personal hygiene and accounting for approximately 97% of food borne illnesses in food service establishments and homes. Our objective was to evaluate the efficacy of hand washing practices and sanitation before commencing work among food handlers in the convenient food industry in Gauteng, South Africa. A total of 230 samples were collected, involving 100% of the food handlers, in 8 selected convenient food outlets with their main focus on preparing ready-to-eat foods. The workers' cleaned and disinfected dominant hands were sampled for Total Plate Count (TPC), Staphylococcus aureus and Escherichia coli. Bacteria were isolated and counted using standard methods. The highest bacterial count from the hand samples was 7.4 x 10(3) cfu.cm(-2) and the lowest showed no detectable growth. Although hands with a count of 0 cfu.cm(-2) were found in all of the plants, the results indicated that all the plants exceeded the legal limit for food surfaces or hands of < 100 cfu.cm(-2) when the average bacterial counts on hands were compared. Sixty percent of the TPC analysed exceeded the legal limit and only 18% of the food handlers had no bacteria detectable on their hands. One sample tested positive for E. coli and S. aureus could not be detected on the hands of any of the food handlers. The study revealed that hand hygiene is unsatisfactory and may have serious implications for public health due to contamination of food from food handlers' hands. This therefore underlined the importance of further training to improve food handlers' knowledge of good hand washing practices.

Longitudinal changes in white matter disease and cognition in the first year of the Alzheimer disease neuroimaging initiative.

PubMed

Carmichael, Owen; Schwarz, Christopher; Drucker, David; Fletcher, Evan; Harvey, Danielle; Beckett, Laurel; Jack, Clifford R; Weiner, Michael; DeCarli, Charles

2010-11-01

To evaluate relationships between magnetic resonance imaging (MRI)-based measures of white matter hyperintensities (WMHs), measured at baseline and longitudinally, and 1-year cognitive decline using a large convenience sample in a clinical trial design with a relatively mild profile of cardiovascular risk factors. Convenience sample in a clinical trial design. A total of 804 participants in the Alzheimer Disease Neuroimaging Initiative who received MRI scans, cognitive testing, and clinical evaluations at baseline, 6-month follow-up, and 12-month follow-up visits. For each scan, WMHs were detected automatically on coregistered sets of T1, proton density, and T2 MRI images using a validated method. Mixed-effects regression models evaluated relationships between risk factors for WMHs, WMH volume, and change in outcome measures including Mini-Mental State Examination (MMSE), Alzheimer Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), and Clinical Dementia Rating Scale sum of boxes scores. Covariates in these models included race, sex, years of education, age, apolipoprotein E genotype, baseline clinical diagnosis (cognitively normal, mild cognitive impairment, or Alzheimer disease), cardiovascular risk score, and MRI-based hippocampal and brain volumes. Higher baseline WMH volume was associated with greater subsequent 1-year increase in ADAS-Cog and decrease in MMSE scores. Greater WMH volume at follow-up was associated with greater ADAS-Cog and lower MMSE scores at follow-up. Higher baseline age and cardiovascular risk score and more impaired baseline clinical diagnosis were associated with higher baseline WMH volume. White matter hyperintensity volume predicts 1-year cognitive decline in a relatively healthy convenience sample that was similar to clinical trial samples, and therefore should be considered as a covariate of interest at baseline and longitudinally in future AD treatment trials.

Use of zero order diffraction of a grating monochromator towards convenient and sensitive detection of fluorescent analytes in multi fluorophoric systems

NASA Astrophysics Data System (ADS)

Panigrahi, Suraj Kumar; Mishra, Ashok Kumar

2018-02-01

White light excitation fluorescence (WLEF) is known to possess analytical advantage in terms of enhanced sensitivity and facile capture of the entire fluorescence spectral signature of multi component fluorescence systems. Using the zero order diffraction of the grating monochromator on the excitation side of a commercial spectrofluorimeter, it has been shown that WLEF spectral measurements can be conveniently carried out. Taking analyte multi-fluorophoric systems like (i) drugs and vitamins spiked in urine sample, (ii) adulteration of extra virgin olive oil with olive pomace oil and (iii) mixture of fabric dyes, it was observed that there is a significant enhancement of measurement sensitivity. The total fluorescence spectral response could be conveniently analysed using PLS2 regression. This work brings out the ease of the use of a conventional fluorimeter for WLEF measurements.

Application of FTA sample collection and DNA purification system on the determination of CTG trinucleotide repeat size by PCR-based Southern blotting.

PubMed

Hsiao, K M; Lin, H M; Pan, H; Li, T C; Chen, S S; Jou, S B; Chiu, Y L; Wu, M F; Lin, C C; Li, S Y

1999-01-01

Myotonic dystrophy (DM) is caused by a CTG trinucleotide expansion mutation at exon 15 of the myotonic dystrophy protein kinase gene. The clinical severity of this disease correlates with the length of the CTG trinucleotide repeats. Determination of the CTG repeat length has been primarily relied on by Southern blot analysis of restriction enzyme-digested genomic DNA. The development of PCR-based Southern blotting methodology provides a much more sensitive and simpler protocol for DM diagnosis. However, the quality of the template and the high (G+C) ratio of the amplified region hamper the use of PCR on the diagnosis of DM. A modified PCR protocol to amplify different lengths of CTG repeat region using various concentrations of 7deaza-dGTP has been reported (1). Here we describe a procedure including sample collection, DNA purification, and PCR analysis of CTG repeat length without using 7-deaza-dGTP. This protocol is very sensitive and convenient because only a small number of nucleate cells are needed for detection of CTG expansion. Therefore, it could be very useful in clinical and prenatal diagnosis as well as in prevalence study of DM.

Effects of Disasters on Smoking and Relapse: An Exploratory Study of Hurricane Katrina Victims.

PubMed

Lanctot, Jennifer Q; Stockton, Michelle B; Mzayek, Fawaz; Read, Mary; McDevitt-Murphy, Meghan; Ward, Kenneth

2008-01-01

Psychosocial stress maintains cigarette use and precipitates relapse, but little is known about how natural disasters in particular affect smoking. To determine the feasibility of recruiting victims soon after a natural disaster for a survey study, and to assess the types and determinants of changes in smoking behavior resulting from exposure to the disaster. A convenience sample of 35 Hurricane Katrina refugees who had smoked more than 100 cigarettes in their lifetime were surveyed one month after the storm to evaluate changes in smoking behavior. Among a small sample of former smokers, more than half relapsed after Katrina, citing stress, urge, and sadness. Among current smokers, 52% increased their smoking after Katrina by more than half a pack per day on average. Most individuals who increased their smoking or relapsed expressed interest in receiving cessation assistance within the next month. Stress-related increases in smoking and relapse may be common after a natural disaster. Health education professionals have an important role to play in responding to changes in tobacco use in the aftermath of disasters. Educational interventions to discourage tobacco use as a coping strategy may be especially warranted given the high level of interest expressed in smoking cessation.

Act-Frequency Signatures of the Big Five.

PubMed

Chapman, Benjamin P; Goldberg, Lewis R

2017-10-01

The traditional focus of work on personality and behavior has tended toward "major outcomes" such as health or antisocial behavior, or small sets of behaviors observable over short periods in laboratories or in convenience samples. In a community sample, we examined a wide set (400) of mundane, incidental or "every day" behavioral acts, the frequencies of which were reported over the past year. Using an exploratory methodology similar to genomic approaches (relying on the False Discovery Rate) revealed 26 prototypical acts for Intellect, 24 acts for Extraversion, 13 for Emotional Stability, nine for Conscientiousness, and six for Agreeableness. Many links were consistent with general intuition-for instance, low Conscientiousness with work and procrastination. Some of the most robust associations, however, were for acts too specific for a priori hypothesis. For instance, Extraversion was strongly associated with telling dirty jokes, Intellect with "loung[ing] around [the] house without clothes on", and Agreeableness with singing in the shower. Frequency categories for these acts changed with markedly non-linearity across Big Five Z-scores. Findings may help ground trait scores in emblematic acts, and enrich understanding of mundane or common behavioral signatures of the Big Five.

Children facing a family member's acute illness: a review of intervention studies.

PubMed

Spath, Mary L

2007-07-01

A review of psycho-educational intervention studies to benefit children adapting to a close (parent, sibling, or grandparent) family member's serious illness was conducted. To review the literature on studies addressing this topic, critique research methods, describe clinical outcomes, and make recommendations for future research efforts. Research citations from 1990 to 2005 from Medline, CINAHL, Health Source: Nursing/Academic Edition, PsycARTICLES, and PsycINFO databases were identified. Citations were reviewed and evaluated for sample, design, theoretical framework, intervention, threats to validity, and outcomes. Reviewed studies were limited to those that included statistical analysis to evaluate interventions and outcomes. Six studies were reviewed. Positive outcomes were reported for all of the interventional strategies used in the studies. Reviewed studies generally lacked a theoretical framework and a control group, were generally composed of small convenience samples, and primarily used non-tested investigator instruments. They were diverse in terms of intervention length and intensity, and measured short-term outcomes related to participant program satisfaction, rather than participant cognitive and behavioral change. The paucity of interventional studies and lack of systematic empirical precision to evaluate intervention effectiveness necessitates future studies that are methodologically rigorous.

Hydrophilic interaction chromatography (HILIC) in the analysis of antibiotics.

PubMed

Kahsay, Getu; Song, Huiying; Van Schepdael, Ann; Cabooter, Deirdre; Adams, Erwin

2014-01-01

This paper presents a general overview of the application of hydrophilic interaction chromatography (HILIC) in the analysis of antibiotics in different sample matrices including pharmaceutical, plasma, serum, fermentation broths, environmental water, animal origin, plant origin, etc. Specific applications of HILIC for analysis of aminoglycosides, β-lactams, tetracyclines and other antibiotics are reviewed. HILIC can be used as a valuable alternative LC mode for separating small polar compounds. Polar samples usually show good solubility in the mobile phase containing some water used in HILIC, which overcomes the drawbacks of the poor solubility often encountered in normal phase LC. HILIC is suitable for analyzing compounds in complex systems that elute near the void in reversed-phase chromatography. Ion-pair reagents are not required in HILIC which makes it convenient to couple with MS hence its increased popularity in recent years. In this review, the retention mechanism in HILIC is briefly discussed and a list of important applications is provided including main experimental conditions and a brief summary of the results. The references provide a comprehensive overview and insight into the application of HILIC in antibiotics analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

Transcobalamin II (TCN2 67A>G and TCN2 776C>G) and transcobalamin II receptor (TCblR 1104C>T) polymorphisms in Korean patients with idiopathic recurrent spontaneous abortion.

PubMed

Kim, Hyun Seok; Lee, Bo Eun; Jeon, Young Joo; Rah, HyungChul; Lee, Woo Sik; Shin, Ji Eun; Choi, Dong Hee; Kim, Nam Keun

2014-09-01

The transcobalamin II (TCN2) 776C>G polymorphism has been reported to be a genetic risk factor for idiopathic recurrent spontaneous abortion (RSA). However, the sample size in previous studies was small, and other TCN2 polymorphisms have not been studied. Moreover, the TCN2 67A>G and 776C>G polymorphisms, and the transcobalamin II receptor (TCblR/CD320) 1104C>T polymorphism, have demonstrated associations with immune responses. Three hundred and seventy-eight RSA patients who had at least two consecutive spontaneous abortions were enrolled. Two hundred and seven control subjects were collected from a convenience sample. Polymerase chain reaction and restriction fragment length polymorphism analysis were performed to identify the TCN2 67A>G and 776C>G polymorphisms, and the TCblR 1104C>T polymorphism. RSA patients showed significantly different frequencies of the TCN2 67AG+GG genotypes compared with control subjects. The TCN2 67G allele is a possible risk factor for idiopathic RSA. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sociodemographic Characteristics of Cannabis Smokers and the Experience of Cannabis Withdrawal

PubMed Central

Copersino, Marc L.; Boyd, Susan J.; Tashkin, Donald P.; Huestis, Marilyn A.; Heishman, Stephen J.; Dermand, John C.; Simmons, Michael S.; Gorelick, David A.

2011-01-01

Background Cannabis withdrawal can be a negative reinforcer for relapse, but little is known about its association with demographic characteristics. Objectives Evaluate the association of demographic characteristics with the experience of cannabis withdrawal. Methods Retrospective self-report of a “serious” cannabis quit attempt without formal treatment in a convenience sample of 104 non-treatment-seeking, adult cannabis smokers (mean age 35 years, 52% white, 78% male) with no other current substance use disorder (except tobacco) or chronic health problems. Reasons for quitting, coping strategies to help quit, and 18 specific withdrawal symptoms were assessed by questionaire. Results Among withdrawal symptoms, only anxiety, increased sex drive, and craving showed significant associations with age, race, or sex. Women were more likely than men to report a physical withdrawal symptom (OR = 3.2, 95% CI = .99–10.4, p = .05), especially upset stomach. There were few significant demographic associations with coping strategies or reasons for quitting. Conclusions and Scientific Significance This small study suggests that there are few robust associations between demographic characteristics and cannabis withdrawal. Future studies with larger samples are needed. Attention to physical withdrawal symptoms in women may help promote abstinence. PMID:20678028

Airport surveys at travel destinations--underutilized opportunities in travel medicine research?

PubMed

Bauer, Irmgard L

2015-01-01

Research in destination airports, especially in resource-poor areas, allows unique immediate access to travelers at the conclusion of their trip. Response rates are high and the recall gap small. Trip-related health matters can be elicited relatively easily. An insight into travelers' decision-making processes on location would fill large gaps in our knowledge regarding travel health advice provision; yet, this approach is still much underutilized. Using PubMed, ScienceDirect, Google Scholar, and ProQuest, a review of the literature on airport surveys was conducted to determine where they were used, their response rates and purpose, and location-relevant methodological information. The lack of methodological guidelines in the reviewed literature resulted in recommendations for planning and conducting an airport survey at a destination airport. Millions of travelers in airports around the world represent an underutilized sample of potential study participants for topics that cannot be studied adequately in other settings. Benefiting from close cooperation between travel health professionals and airport authorities, researchers can expect not only large-scale convenience samples for surveys, but also opportunities to explore exciting and creative research topics to broaden our understanding of travel medicine and health. © 2014 International Society of Travel Medicine.

Mechanistic and "natural" body metaphors and their effects on attitudes to hormonal contraception.

PubMed

Walker, Susan

2012-01-01

A small, self-selected convenience sample of male and female contraceptive users in the United Kingdom (n = 34) were interviewed between 2006 and 2008 concerning their feelings about the body and their contraceptive attitudes and experiences. The interviewees were a sub-sample of respondents (n = 188) who completed a paper-based questionnaire on similar topics, who were recruited through a poster placed in a family planning clinic, web-based advertisements on workplace and university websites, and through direct approaches to social groups. The bodily metaphors used when discussing contraception were analyzed using an interpretative phenomenological analytical approach facilitated by Atlas.ti software. The dominant bodily metaphor was mechanistic (i.e.,"body as machine"). A subordinate but influential bodily metaphor was the "natural" body, which had connotations of connection to nature and a quasi-sacred bodily order. Interviewees drew upon this "natural" metaphorical image in the context of discussing their anxieties about hormonal contraception. Drawing upon a "natural," non-mechanistic body image in the context of contraceptive decision-making contributed to reluctance to use a hormonal form of contraception. This research suggests that clinicians could improve communication and advice about contraception by recognizing that some users may draw upon non-mechanistic body imagery.

Automated sample-changing robot for solution scattering experiments at the EMBL Hamburg SAXS station X33

PubMed Central

Round, A. R.; Franke, D.; Moritz, S.; Huchler, R.; Fritsche, M.; Malthan, D.; Klaering, R.; Svergun, D. I.; Roessle, M.

2008-01-01

There is a rapidly increasing interest in the use of synchrotron small-angle X-ray scattering (SAXS) for large-scale studies of biological macromolecules in solution, and this requires an adequate means of automating the experiment. A prototype has been developed of an automated sample changer for solution SAXS, where the solutions are kept in thermostatically controlled well plates allowing for operation with up to 192 samples. The measuring protocol involves controlled loading of protein solutions and matching buffers, followed by cleaning and drying of the cell between measurements. The system was installed and tested at the X33 beamline of the EMBL, at the storage ring DORIS-III (DESY, Hamburg), where it was used by over 50 external groups during 2007. At X33, a throughput of approximately 12 samples per hour, with a failure rate of sample loading of less than 0.5%, was observed. The feedback from users indicates that the ease of use and reliability of the user operation at the beamline were greatly improved compared with the manual filling mode. The changer is controlled by a client–server-based network protocol, locally and remotely. During the testing phase, the changer was operated in an attended mode to assess its reliability and convenience. Full integration with the beamline control software, allowing for automated data collection of all samples loaded into the machine with remote control from the user, is presently being implemented. The approach reported is not limited to synchrotron-based SAXS but can also be used on laboratory and neutron sources. PMID:25484841

Women's views on human papillomavirus self-sampling: focus groups to assess acceptability, invitation letters and a test kit in the Australian setting.

PubMed

Sultana, Farhana; Mullins, Robyn; Murphy, Michael; English, Dallas R; Simpson, Julie A; Drennan, Kelly T; Heley, Stella; Wrede, C David; Brotherton, Julia M L; Saville, Marion; Gertig, Dorota M

2015-08-01

Background The study evaluated acceptability, invitation letters and the test kit for a trial of human papillomavirus (HPV) self-sampling among never- and under-screened women in Australia. Victorian women, 30-69 years, who had never had a Pap test or were overdue for one, participated. Four focus groups including eight to nine participants segmented by age (30-49 and 50-69 years) and screening history (never- and under-screened) were conducted in August 2013. Discussions were recorded and transcribed verbatim and data analysed using thematic content analysis. The response to the concept of HPV self-sampling was positive. Decision-making was largely influenced by the content of a pre-invitation letter. Appealing features of self-sampling were cost (free), convenience (home-based) and anticipated less discomfort (with a swab) than a Pap test. Small kits that fit in mailboxes were preferred over post office parcel collection. The perceived barriers include concerns about test accuracy and lack of confidence that a home-based test would give the same results as a physician administered test. Women wanted information on the timing of receipt of the results and information about the organisation providing the test. HPV self-sampling is a possible alternative for Australian women who are reluctant to have a Pap test and may increase the likelihood of participation in cervical cancer screening if women's concerns about it can be addressed. The findings of this study are relevant for researchers, policymakers and practitioners implementing self-sampling for under-screened women as part of cervical screening programs.

A Pilot Study of Children's Blood Lead Levels in Mount Isa, Queensland.

PubMed

Green, Donna; Sullivan, Marianne; Cooper, Nathan; Dean, Annika; Marquez, Cielo

2017-12-13

Mount Isa, Queensland, is one of three Australian cities with significant lead emissions due to nonferrous mining and smelting. Unlike the two other cities with lead mines or smelters, Mount Isa currently has no system of annual, systematic, community-wide blood lead level testing; and testing rates among Indigenous children are low. In previous screenings, this group of children has been shown to have higher average blood lead levels than non-Indigenous children. The first aim of this study was to assess whether parents and children would participate in less invasive, rapid point-of-care capillary testing. The second aim was to measure blood lead levels among a range of children that roughly reflected the percentage of the Indigenous/non-Indigenous population. This pilot study is based on a convenience sample of children between the ages of 12 and 83 months who were recruited to participate by staff at a Children and Family Centre. Over three half-days, 30 children were tested using capillary blood samples and the LeadCare II Point-of-Care testing system. Rapid point-of-care capillary testing was well tolerated by the children. Of 30 children tested, 40% ( n = 12) had blood lead levels ≥5 µg/dL and 10% had levels ≥10 µg/dL. The highest blood lead level measured was 17.3 µg/dL. The percentage of children with blood lead levels ≥5 µg/dL was higher among Indigenous children compared to non-Indigenous (64.2% compared to 18.8%) as was the geometric mean level (6.5 (95% CI, 4.7, 9.2) versus 2.4 (95% CI, 1.8, 3.1)), a statistically significant difference. Though based on a small convenience sample, this study identified 12 children (40%) of the sample with blood lead levels ≥5 µg/dL. Due to historical and ongoing heavy metal emissions from mining and smelting in Mount Isa, we recommend a multi-component program of universal blood lead level testing, culturally appropriate follow-up and intervention for children who are identified with blood lead levels ≥5 µg/dL. We further recommend focused outreach and assistance to the Indigenous community, and further control of emissions and remediation of existing environmental lead contamination in children's play and residential areas.

A Development of Learning Widget on M-Learning and E-Learning Environments

ERIC Educational Resources Information Center

Kim, SooHwan; Kim, HyeonCheol; Han, SeonKwan

2013-01-01

This article describes the development of learning widget on m-learning and e-learning environments. A widget is a small, simple and useful application supporting user-oriented contents. The user may select and install widgets that are convenient as well as an auto-updating application including weather or calendar. These widgets are especially…

Organic Materials in the Undergraduate Laboratory: Microscale Synthesis and Investigation of a Donor-Acceptor Molecule

ERIC Educational Resources Information Center

Pappenfus, Ted M.; Schliep, Karl B.; Dissanayake, Anudaththa; Ludden, Trevor; Nieto-Ortega, Belen; Lopez Navarrete, Juan T.; Ruiz Delgado, M. Carmen; Casado, Juan

2012-01-01

A series of experiments for undergraduate courses (e.g., organic, physical) have been developed in the area of small molecule organic materials. These experiments focus on understanding the electronic and redox properties of a donor-acceptor molecule that is prepared in a convenient one-step microscale reaction. The resulting intensely colored…

Food Shopping Perceptions, Behaviors, and Ability to Purchase Healthful Food Items in the Lower Mississippi Delta

ERIC Educational Resources Information Center

McGee, Bernestine B.; Johnson, Glenda S.; Yadrick, M. Kathleen; Richardson, Valerie; Simpson, Pippa M.; Gossett, Jeffrey M.; Thornton, Alma; Johnson, Crystal; Bogle, Margaret L.

2011-01-01

Objective: To examine the agreement between perceptions, behaviors, and ability to purchase healthful food in the Lower Mississippi Delta (LMD). Design: A regional food store survey of healthful food options in supermarkets, small/medium stores, and convenience stores. Focus group discussions were conducted on shopping perceptions and behaviors.…

A Simple Solution to Providing Remote Access to CD-ROM.

ERIC Educational Resources Information Center

Garnham, Carla T.; Brodie, Kent

1990-01-01

A pilot project at the Medical College of Wisconsin illustrates how even small computing organizations with limited financial and staff resources can provide remote access to CD-ROM (Compact Disc-Read-Only-Memory) databases, and that providing such convenient access to a vast array of useful information can greatly benefit faculty and students.…

75 FR 42740 - Ryckman Creek Resources, LLC; Notice of Intent To Prepare an Environmental Assessment for the...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-22

.... Create a central gas/liquids separation facility (Ryckman Plant) where all of the gas pipelines meet. It would contain a small electric-driven compressor to compress casing head gas, liquids separation... Convenience and Necessity under section 7 of the Natural Gas Act. The Bureau of Land Management (BLM) is...

SAS procedures for designing and analyzing sample surveys

USGS Publications Warehouse

Stafford, Joshua D.; Reinecke, Kenneth J.; Kaminski, Richard M.

2003-01-01

Complex surveys often are necessary to estimate occurrence (or distribution), density, and abundance of plants and animals for purposes of re-search and conservation. Most scientists are familiar with simple random sampling, where sample units are selected from a population of interest (sampling frame) with equal probability. However, the goal of ecological surveys often is to make inferences about populations over large or complex spatial areas where organisms are not homogeneously distributed or sampling frames are in-convenient or impossible to construct. Candidate sampling strategies for such complex surveys include stratified,multistage, and adaptive sampling (Thompson 1992, Buckland 1994).

An affordable and easy-to-use diagnostic method for keratoconus detection using a smartphone

NASA Astrophysics Data System (ADS)

Askarian, Behnam; Tabei, Fatemehsadat; Askarian, Amin; Chong, Jo Woon

2018-02-01

Recently, smartphones are used for disease diagnosis and healthcare. In this paper, we propose a novel affordable diagnostic method of detecting keratoconus using a smartphone. Keratoconus is usually detected in clinics with ophthalmic devices, which are large, expensive and not portable, and need to be operated by trained technicians. However, our proposed smartphone-based eye disease detection method is small, affordable, portable, and it can be operated by patients in a convenient way. The results show that the proposed keratoconus detection method detects severe, advanced, and moderate keratoconus with accuracies of 93%, 86%, 67%, respectively. Due to its convenience with these accuracies, the proposed keratoconus detection method is expected to be applied in detecting keratoconus at an earlier stage in an affordable way.

Predictive role of computer simulation in assessing signaling pathways of crizotinib-treated A549 lung cancer cells.

PubMed

Xia, Pu; Mou, Fei-Fei; Wang, Li-Wei

2012-01-01

Non-small-cell lung cancer (NSCLC) is a leading cause of cancer deaths worldwide. Crizotinib has been approved by the U.S. Food and Drug Administration for the treatment of patients with advanced NSCLC. However, understanding of mechanisms of action is still limited. In our studies, we confirmed crizotinib-induced apoptosis in A549 lung cancer cells. In order to assess mechanisms, small molecular docking technology was used as a preliminary simulation of signaling pathways. Interesting, our results of experiments were consistent with the results of computer simulation. This indicates that small molecular docking technology should find wide use for its reliability and convenience.

Filtrates & Residues: A Convenient, Low-Cost Method for Determining Sulfate in Acid Rain.

ERIC Educational Resources Information Center

Johns, Nicholas; Longstaff, Stephen J.

1987-01-01

Describes efforts in devising a method for determining sulfate quickly and accurately from rainwater samples. Explains the design and operation of the apparatus and identifies the solutions for the testing. (ML)

78 FR 59001 - Chlorinated Isocyanurates From the People's Republic of China: Initiation of Countervailing Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-25

... required by subparagraph (A); or (ii) determine industry support using a statistically valid sampling... provided for convenience and customs purposes. The written description of the scope of the investigation is...

75 FR 68360 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-05

... greater proportions of the HIV epidemic. A convenience sample will be used to select attendees at (1) Gay Pride; (2) Minority Gay Pride; (3) black spring break; and (4) cultural and social events attracting...

A method suitable for DNA extraction from humus-rich soil.

PubMed

Miao, Tianjin; Gao, Song; Jiang, Shengwei; Kan, Guoshi; Liu, Pengju; Wu, Xianming; An, Yingfeng; Yao, Shuo

2014-11-01

A rapid and convenient method for extracting DNA from soil is presented. Soil DNA is extracted by direct cell lysis in the presence of EDTA, SDS, phenol, chloroform and isoamyl alcohol (3-methyl-1-butanol) followed by precipitation with 2-propanol. The extracted DNA is purified by modified DNA purification kit and DNA gel extraction kit. With this method, DNA extracted from humus-rich dark brown forest soil was free from humic substances and, therefore, could be used for efficient PCR amplification and restriction digestion. In contrast, DNA sample extracted with the traditional CTAB-based method had lower yield and purity, and no DNA could be extracted from the same soil sample with a commonly-used commercial soil DNA isolation kit. In addition, this method is time-saving and convenient, providing an efficient choice especially for DNA extraction from humus-rich soils.

Construction Workers Struggle with a High Prevalence of Mental Distress and this is Associated with Their Pain and Injuries

PubMed Central

Jacobsen, Henrik Borsting; Caban-Martinez, Alberto; Onyebeke, Lynn C.; Sorensen, Glorian; Dennerlein, Jack T.; Reme, Silje Endresen

2013-01-01

Objectives We aimed to investigate how mental distress was associated with pain and injuries in a convenience sample of construction workers. Methods A cross-sectional, mental health assessment was conducted in a convenience sample of construction workers (N=172). A subsample participated in a clinical interview (N=10). We used a cut-off (≥1.50) on HSCL-25 to determine substantial mental distress and determined associations with pain and injury outcomes. Results The prevalence of substantial mental distress was 16 % in the workers. This was supported by follow-up clinical interviews where nine out of ten workers fulfilled the criteria for a mental disorder. Substantial mental distress was associated with both injury rate and self-reported pain. Conclusion This pilot study strongly suggests the need for rigorous studies on construction worker mental health, and how it affects their work and wellbeing. PMID:24064778

Water sample filtration unit

USGS Publications Warehouse

Skougstad, M.W.; Scarbro, G.F.

1968-01-01

A readily portable, all plastic, pressure filtration unit is described which greatly facilitates rapid micropore membrane field filtration of up to several liters of water with a minimum risk of inorganic chemical alteration or contamination of the sample. The unit accommodates standard 10.2-cm. (4-inch) diameter filters. The storage and carrying case serves as a convenient filter stand for both field and laboratory use.

Childhood Sexual Abuse as a Predictor of Birth-Related Posttraumatic Stress and Postpartum Posttraumatic Stress

ERIC Educational Resources Information Center

Lev-Wiesel, Rachel; Daphna-Tekoah, Shir; Hallak, Mordechai

2009-01-01

Objective: To investigate the extent to which childbirth may function as a retraumatization of childhood sexual abuse, and may exacerbate postpartum posttraumatic stress reactions. Methods: Data was obtained from a convenience sample of 837 women in mid-pregnancy, at 2 and 6 months following childbirth. Three groups were drawn from this sample:…

An Investigation on Balance between Professional and Personal Work of Women Teachers

ERIC Educational Resources Information Center

Priya, J. Johnsi

2017-01-01

The present study aims to examine the work-life balance of women teachers in Chennai city. In this normative survey study, 100 women teachers were selected as sample by using convenient sampling technique. The data were collected from 100 women teachers who are working in eight Higher Secondary Schools at chennai city using the Work-life Balance…

Attitudes Towards Seeking Psychological Help among a Sample of Turkish University Students: The Roles of Rumination and Internal Working Models

ERIC Educational Resources Information Center

Turan, Numan; Erdur-Baker, Özgür

2014-01-01

The current study investigates how attitudes towards seeking psychological help relate to internal working models of attachment (self-model and other-model) and ruminative tendencies. The study includes 589 Turkish university students (278 females, 308 males and 3 unknown) by implementing a convenient sampling procedure. The average age of the…

Romanian, Spanish and US Secondary Science Teacher Perceptions of Threats to the Biosphere

ERIC Educational Resources Information Center

Robinson, Michael; Naumescu, Adrienne Kozan; Ives, Bob

2009-01-01

This paper presents the data from a current study involving 41 Romanian secondary science teachers and a previously published study that compared 89 Spanish and 42 US secondary science teachers. All three groups were convenience samples who answered a two part questionnaire that was given in English, Spanish or Romanian, depending on the sample.…

[Survey of what is published on Italian nursing journals].

PubMed

Bongiorno, Elena; Colleoni, Pasqualina; Casati, Monica

2005-01-01

Nursing research is an important activity for nurses; the main aim is to improve the quality of nursing. Several national and european laws have been issued about it. To develop knowledge about nursing, nurses have to understand the results of researches, implement them in the different situation and sometimes carry out researches. The results can be published in nursing journals which a lot of nurses use to share information. This study reviewed the characteristics of research articles published in italian nursing journals from 1998 to 2003. Phenomena of interest are: areas of enquiry, investigators, methods, research design, sampling and means to gather data. 122 articles have been reviewed: 78% focus on clinical aspects, 55% were carry out by nurses, 92% adopt the quantitative approach, 90% used non experimental design, 89% used convenience selection sampling method and 58% answer ways. The characteristics of this study are similar to other studies about italian nursing publication. There are some limits in this type of literature: lower generalization because of lower representativeness of sample, convenience selection sampling method, and higher risk of interference due to frequent use of non experimental design. However the number of italian nurses that carry out researches is increasing and nursing is the most studied area.

Evaluations of sampling methods for darkling beetles (Alphitobius diaperinus) in the litter of turkey and broiler houses.

PubMed

Safrit, R D; Axtell, R C

1984-12-01

Materials placed on the litter in turkey and broiler houses were evaluated as sampling devices for the larvae and adults of Alphitobius diaperinus (lesser mealworm or darkling beetle). Insects harbored in, on, and between pieces of the materials were counted after 1-week exposure. Pan traps consisting of two stacked pieces of 1.3-cm thick foil-covered polyisocyanurate insulation (Celotex) placed under a protective metal pan staked to the litter surface was a more effective sampling device than pan traps using thicker (5 cm) Celotex, 3.8 cm thick polystyrene (Styrofoam), or two stacked pieces of wood. A tube trap consisting of rolled fluted corrugated cardboard inserted in a section of polyvinyl chloride pipe was as effective a sampling device as the two pieces of Celotex in a pan trap and was more convenient to use. Six pieces of corrugated cardboard stacked under a pan caught larger numbers of beetle larvae and adults but was awkward to handle and impractical. Placement of sampling devices in the major subhabitats (open center, near walls, near feeders, and near waterers) in turkey and broiler houses affected catches of beetle larvae and adults. The open center area was satisfactory and most convenient.

Characterization of pesticide exposure in a sample of pregnant women in Ecuador

PubMed Central

Handal, Alexis J.; Hund, Lauren; Páez, Maritza; Bear, Samantha; Greenberg, Carolyn; Fenske, Richard A.; Barr, Dana Boyd

2015-01-01

Background Few studies have detailed the prenatal pesticide exposure levels of women employed in or residing near large-scale agricultural industries. This study reports pesticide metabolite levels during and shortly after pregnancy in a pilot study of workers in Ecuador. Methods Urine samples were collected for 16 rose workers and 10 non-agricultural workers enrolled into the study in early pregnancy. We measured six nonspecific organophosphate dialkylphosphate (DAP) pesticide metabolites, two alkylenebis-dithiocarbamate pesticide metabolites (ethylene thiourea [ETU] and propylene thiourea [PTU]), 3,5,6-trichloro-2-pyridinol [TCPy], malathion dicarboxylic acid, and two pyrethroid metabolites (2,2-dimethylcyclopropanecarboxylic acid and 3-phenooxybenzoic acid). Results We collected 141 urine samples (mean: 5.4 per woman). We observed high detection frequencies for five DAP metabolites and ETU, PTU, and TCPy. We report elevated levels of ETU in the entire sample (median 4.24 ng/mL, IQR 2.23, 7.18), suggesting other possible non-occupational pathways of exposure. We found no statistical differences in pesticide levels by current employment status, though the highest pesticide levels were among rose workers. We observed within-woman correlation in TCPy and PTU levels, but not in ETU or DAP levels. Conclusions The present study is the first to characterize prenatal pesticide exposure levels among working women in Ecuador. Limitations include a small sample size and use of a convenience sample. Strengths include a longitudinal design and multiple urine samples per woman. Results provide an initial characterization of prenatal pesticide exposure levels and how these levels vary over pregnancy in a community impacted by agricultural industry and will inform further studies in the region. PMID:26311023

Possible relationships between literacy-based instructional coaching and effects on high school teachers' self-efficacy and attitudes toward teaching reading in the content areas

NASA Astrophysics Data System (ADS)

Jacobs, Jessica Lynn

Grounded in the Theory of Self-Efficacy and the Theory of Reasoned Action, this quantitative, correlational study examined if participation in literacy-based instructional coaching (one-on-one, small group) predicted both high school teachers' self-efficacy as measured by the Teachers' Sense of Efficacy Scale and teachers' attitudes toward teaching reading in the content areas measured by the Scale to Measure Attitudes Toward Teaching Reading in Content Classrooms. This study utilized a convenience sample of content teachers from three high schools in Northeastern Pennsylvania participating in a literacy coaching initiative. The volunteer sample of teachers completed the Likert-type questionnaires. The study used hierarchical regression analysis to determine values for each block of the regression models. The study correlated instances of literacy-based instructional coaching (one-on-one, small group) with the scores on the SMATTRCC and the TSES to examine predictive validity. Gender, years of experience, and content area were control variables in this study. The results of the first model indicated that there was a significant relationship between the number of coaching instances and attitudes toward teaching reading in the content area with participation in instructional coaching accounting for 9.6% of the variance in scores on the SMATTRCC. The results of the second model indicated that there was a significant relationship between the number of coaching instances and teachers' self-efficacy with participation in instructional coaching accounting for 6.1% of the variance in scores on the TSES.

Exploring the opinions of registered nurses working in a clinical transfusion environment on the contribution of e-learning to personal learning and clinical practice: results of a small scale educational research study.

PubMed

Cottrell, Susan; Donaldson, Jayne H

2013-05-01

To explore the opinions of registered nurses on the Learnbloodtransfusion Module 1: Safe Transfusion Practice e-learning programme to meeting personal learning styles and learning needs. A qualitative research methodology was applied based on the principles of phenomenology. Adopting a convenience sampling plan supported the recruitment of participants who had successfully completed the e-learning course. Thematic analysis from the semi-structured interviews identified common emerging themes through application of Colaizzis framework. Seven participants of total sample population (89) volunteered to participate in the study. Five themes emerged which included learning preferences, interactive learning, course design, patient safety and future learning needs. Findings positively show the e-learning programme captures the learning styles and needs of learners. In particular, learning styles of a reflector, theorist and activist as well as a visual learner can actively engage in the online learning experience. In an attempt to bridge the knowledge practice gap, further opinions are offered on the course design and the application of knowledge to practice following completion of the course. The findings of the small scale research study have shown that the e-learning course does meet the diverse learning styles and needs of nurses working in a clinical transfusion environment. However, technology alone is not sufficient and a blended approach to learning must be adopted to meet bridging the theory practice gap supporting the integration of knowledge to clinical practice. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cyber dating violence: Prevalence and correlates among high school students from small urban areas in Quebec.

PubMed

Smith, Kevin; Cénat, Jude Mary; Lapierre, Andréanne; Dion, Jacinthe; Hébert, Martine; Côté, Karine

2018-07-01

Adolescents in a dating relationship can interact anytime using information and communication technologies. Yet, despite associated potential benefits, this availability of means to reach out to their partner may also exacerbate possible conflictual exchanges, including dating violence through technology. This study aimed to document the prevalence of cyber dating violence (CDV) victimization and perpetration among teenagers. It also explored self-esteem and psychological distress in participants having been perpetrators, victims, or perpetrator-victims, compared with those not having experienced CDV. The sample comprised 190 teenagers from a small urban area who completed the K10 psychological distress scale, the Self-Description Questionnaire, which measures self-esteem, and the Cyber Dating Abuse Questionnaire, which measures the prevalence of CDV victimization and perpetration. Our results suggest no gender difference in the prevalence of CDV victimization (35.8%), perpetration (33.0%), or the high co-occurrence rate of victimization and perpetration (27.2%) in the last 12 months. When age and gender were controlled for, cyber dating violence was found to be associated with low self-esteem and psychological distress in teenagers. Cyberperpetration was also associated with higher self-esteem. The cross-sectional design precludes any conclusion about the sequencing of the variables. Reliance on a convenience sample also represents a limitation of the study. CDV is associated with low self-esteem and psychological distress in teenagers. Dating violence prevention programs should include issues related to CDV, considering its high prevalence, conceptual proximity to psychological violence, and relationship with psychological distress and low self esteem. Copyright © 2018 Elsevier B.V. All rights reserved.

Syringe needle-based sampling coupled with liquid-phase extraction for determination of the three-dimensional distribution of l-ascorbic acid in apples.

PubMed

Tang, Sheng; Lee, Hian Kee

2016-05-15

A novel syringe needle-based sampling approach coupled with liquid-phase extraction (NBS-LPE) was developed and applied to the extraction of l-ascorbic acid (AsA) in apple. In NBS-LPE, only a small amount of apple flesh (ca. 10mg) was sampled directly using a syringe needle and placed in a glass insert for liquid extraction of AsA by 80 μL oxalic acid-acetic acid. The extract was then directly analyzed by liquid chromatography. This new procedure is simple, convenient, almost organic solvent free, and causes far less damage to the fruit. To demonstrate the applicability of NBS-LPE, AsA levels at different sampling points in a single apple were determined to reveal the spatial distribution of the analyte in a three-dimensional model. The results also showed that this method had good sensitivity (limit of detection of 0.0097 mg/100g; limit of quantification of 0.0323 mg/100g), acceptable reproducibility (relative standard deviation of 5.01% (n=6)), a wide linear range of between 0.05 and 50mg/100g, and good linearity (r(2)=0.9921). This interesting extraction technique and modeling approach can be used to measure and monitor a wide range of compounds in various parts of different soft-matrix fruits and vegetables, including single specimens. Copyright © 2015 Elsevier Ltd. All rights reserved.

Specialized disaster behavioral health training: Its connection with response, practice, trauma health, and resilience

PubMed Central

Atkins, Christiana D.; Burnett,, Harvey J.

2016-01-01

Abstract This study examined the relationship between having training in key disaster behavioral health (DBH) interventions and trauma health (compassion fatigue, burnout and compassion satisfaction), resilience, the number of crisis responses participated in within the last year, and the frequency of assembling to practice crisis interventions skills. Data was collected from a convenience sample of disaster behavioral health responders (N = 139) attending a training conference in Michigan. Measures included the Professional Quality of Life Scale, the 14-item Resilience Scale, and a demographic questionnaire. Point biserial correlations revealed that having training in large and small group crisis interventions and individual and peer crisis interventions was significantly correlated with higher resilience and lower levels of burnout. Psychological First Aid was not significantly associated with any of the trauma health variables or with resilience. Compassion fatigue and compassion satisfaction were not significantly associated with DBH training. Chi-square tests for independence found no significant association between key DBH training strategies and the number of crisis responses participated in within the past year and the frequency of assembling to practice crisis interventions skills. These findings suggest that completing training in both, large and small group and individual and peer crisis intervention techniques may help to increase resiliency and reduce burnout among disaster behavioral health providers. PMID:28229015

Optimising in situ gamma measurements to identify the presence of radioactive particles in land areas.

PubMed

Rostron, Peter D; Heathcote, John A; Ramsey, Michael H

2014-12-01

High-coverage in situ surveys with gamma detectors are the best means of identifying small hotspots of activity, such as radioactive particles, in land areas. Scanning surveys can produce rapid results, but the probabilities of obtaining false positive or false negative errors are often unknown, and they may not satisfy other criteria such as estimation of mass activity concentrations. An alternative is to use portable gamma-detectors that are set up at a series of locations in a systematic sampling pattern, where any positive measurements are subsequently followed up in order to determine the exact location, extent and nature of the target source. The preliminary survey is typically designed using settings of detector height, measurement spacing and counting time that are based on convenience, rather than using settings that have been calculated to meet requirements. This paper introduces the basis of a repeatable method of setting these parameters at the outset of a survey, for pre-defined probabilities of false positive and false negative errors in locating spatially small radioactive particles in land areas. It is shown that an un-collimated detector is more effective than a collimated detector that might typically be used in the field. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Occlusal wear and occlusal condition in a convenience sample of young adults.

PubMed

Van't Spijker, A; Kreulen, C M; Bronkhorst, E M; Creugers, N H J

2015-01-01

To study progression of tooth wear quantitatively in a convenient sample of young adults and to assess possible correlations with occlusal conditions. Twenty-eight dental students participated in a three-year follow up study on tooth wear. Visible wear facets on full arch gypsum casts were assessed using a flatbed scanner and measuring software. Regression analyses were used to assess possible associations between the registered occlusal conditions 'occlusal guidance scheme', 'vertical overbite', 'horizontal overbite', 'depth of sagittal curve', 'canine Angle class relation', 'history of orthodontic treatment', and 'self-reported grinding/clenching' (independent variables) and increase of wear facets (dependent variable). Mean increase in facet surface areas ranged from 1.2 mm2 (premolars, incisors) to 3.4 mm2 (molars); the relative increase ranged from 15% to 23%. Backward regression analysis showed no significant relation for 'group function', 'vertical overbite', 'depth of sagittal curve', 'history of orthodontic treatment' nor 'self-reported clenching. The final multiple linear regression model showed significant associations amongst 'anterior protected articulation' and 'horizontal overbite' and increase of facet surface areas. For all teeth combined, only 'anterior protected articulation' had a significant effect. 'Self reported grinding' did not have a significant effect (p>0.07). In this study 'anterior protected articulation' and 'horizontal overbite', were significantly associated with the progression of tooth wear. Self reported grinding was not significantly associated with progression of tooth wear. Occlusal conditions such as anterior protected articulation and horizontal overbite seem to have an effect on the progression of occlusal tooth wear in this convenient sample of young adults. Copyright © 2014 Elsevier Ltd. All rights reserved.

Web-based NGS data analysis using miRMaster: a large-scale meta-analysis of human miRNAs.

PubMed

Fehlmann, Tobias; Backes, Christina; Kahraman, Mustafa; Haas, Jan; Ludwig, Nicole; Posch, Andreas E; Würstle, Maximilian L; Hübenthal, Matthias; Franke, Andre; Meder, Benjamin; Meese, Eckart; Keller, Andreas

2017-09-06

The analysis of small RNA NGS data together with the discovery of new small RNAs is among the foremost challenges in life science. For the analysis of raw high-throughput sequencing data we implemented the fast, accurate and comprehensive web-based tool miRMaster. Our toolbox provides a wide range of modules for quantification of miRNAs and other non-coding RNAs, discovering new miRNAs, isomiRs, mutations, exogenous RNAs and motifs. Use-cases comprising hundreds of samples are processed in less than 5 h with an accuracy of 99.4%. An integrative analysis of small RNAs from 1836 data sets (20 billion reads) indicated that context-specific miRNAs (e.g. miRNAs present only in one or few different tissues / cell types) still remain to be discovered while broadly expressed miRNAs appear to be largely known. In total, our analysis of known and novel miRNAs indicated nearly 22 000 candidates of precursors with one or two mature forms. Based on these, we designed a custom microarray comprising 11 872 potential mature miRNAs to assess the quality of our prediction. MiRMaster is a convenient-to-use tool for the comprehensive and fast analysis of miRNA NGS data. In addition, our predicted miRNA candidates provided as custom array will allow researchers to perform in depth validation of candidates interesting to them. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Exploring national surveillance for health-related workplace absenteeism: lessons learned from the 2009 influenza A pandemic.

PubMed

Groenewold, Matthew R; Konicki, Doris L; Luckhaupt, Sara E; Gomaa, Ahmed; Koonin, Lisa M

2013-04-01

During the 2009 influenza A (H1N1) virus pandemic, the Centers for Disease Control and Prevention did a pilot study to test the feasibility of using national surveillance of workplace absenteeism to assess the pandemic's impact on the workplace to plan for preparedness and continuity of operations and to contribute to health awareness during the emergency response. Population-based and sentinel worksite approaches were used. Monthly measures of the 1-week prevalence of health-related absenteeism among full-time workers were estimated using nationally representative data from the Current Population Survey. Enhanced passive surveillance of absenteeism was conducted using weekly data from a convenience sample of sentinel worksites. Nationally, the pandemic's impact on workplace absenteeism was small. Estimates of 1-week absenteeism prevalence did not exceed 3.7%. However, peak workplace absenteeism was correlated with the highest occurrence of both influenza-like illness and influenza-positive laboratory tests. Systems for monitoring workplace absenteeism should be included in pandemic preparedness planning.

Permutation-based inference for the AUC: A unified approach for continuous and discontinuous data.

PubMed

Pauly, Markus; Asendorf, Thomas; Konietschke, Frank

2016-11-01

We investigate rank-based studentized permutation methods for the nonparametric Behrens-Fisher problem, that is, inference methods for the area under the ROC curve. We hereby prove that the studentized permutation distribution of the Brunner-Munzel rank statistic is asymptotically standard normal, even under the alternative. Thus, incidentally providing the hitherto missing theoretical foundation for the Neubert and Brunner studentized permutation test. In particular, we do not only show its consistency, but also that confidence intervals for the underlying treatment effects can be computed by inverting this permutation test. In addition, we derive permutation-based range-preserving confidence intervals. Extensive simulation studies show that the permutation-based confidence intervals appear to maintain the preassigned coverage probability quite accurately (even for rather small sample sizes). For a convenient application of the proposed methods, a freely available software package for the statistical software R has been developed. A real data example illustrates the application. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

NMRbot: Python scripts enable high-throughput data collection on current Bruker BioSpin NMR spectrometers.

PubMed

Clos, Lawrence J; Jofre, M Fransisca; Ellinger, James J; Westler, William M; Markley, John L

2013-06-01

To facilitate the high-throughput acquisition of nuclear magnetic resonance (NMR) experimental data on large sets of samples, we have developed a simple and straightforward automated methodology that capitalizes on recent advances in Bruker BioSpin NMR spectrometer hardware and software. Given the daunting challenge for non-NMR experts to collect quality spectra, our goal was to increase user accessibility, provide customized functionality, and improve the consistency and reliability of resultant data. This methodology, NMRbot, is encoded in a set of scripts written in the Python programming language accessible within the Bruker BioSpin TopSpin ™ software. NMRbot improves automated data acquisition and offers novel tools for use in optimizing experimental parameters on the fly. This automated procedure has been successfully implemented for investigations in metabolomics, small-molecule library profiling, and protein-ligand titrations on four Bruker BioSpin NMR spectrometers at the National Magnetic Resonance Facility at Madison. The investigators reported benefits from ease of setup, improved spectral quality, convenient customizations, and overall time savings.

A Neutron Diffractometer for a Long Pulsed Neutron Source

NASA Astrophysics Data System (ADS)

Sokol, Paul; Wang, Cailin

Long pulsed neutron sources are being actively developed as small university based sources and are being considered for the next generation of high powered sources, such as the European Neutron Source (ESS) and the Spallation Neutron Source (SNS) second target station. New instrumentation concepts will be required to effectively utilize the full spectrum of neutrons generated by these sources. Neutron diffractometers, which utilize time-of-flight (TOF) techniques for wavelength resolution, are particularly problematic. We describe an instrument for a long pulsed source that provides resolution comparable to that obtained on short pulsed sources without the need of long incident flight paths. We accomplish this by utilizing high speed choppers to impose a time structure on the spectrum of incident neutrons. By strategically positioning these choppers the response matrix assumes a convenient form that can be deconvoluted from the measured TOF spectrum to produce the diffraction pattern of the sample. We compare the performance of this instrument to other possible diffraction instruments that could be utilized on a long pulsed source.

Meaning and Posttraumatic Growth Among Survivors of the September 2013 Colorado Floods.

PubMed

Dursun, Pinar; Steger, Michael F; Bentele, Christoph; Schulenberg, Stefan E

2016-12-01

In the wake of significant adversity, a range of recovery outcomes are possible, from prolonged distress to minimal effects on functioning and even psychological growth. Finding meaning in one's life is thought to facilitate optimal recovery from such adversity. Research on psychological growth and recovery often focuses on the daily hassles or significant traumas of convenience samples or on people's psychological recovery from medical illness. A small body of research is developing to test theories of growth among survivors of natural disasters. The present study of 57 survivors of the 2013 Colorado floods tested the incremental relations between posttraumatic growth (PTG) and dimensions of meaning in life, vitality, and perceived social support. The most consistent relations observed were among the one dimension of meaning-search for meaning-perceived social support, and PTG. Despite the limitations of this study, we conclude that search for meaning in life may be an important part of recovery from natural disasters, floods being one example. © 2016 Wiley Periodicals, Inc.

Exploring role confusion in nurse case management.

PubMed

Gray, Frances C; White, Ann; Brooks-Buck, Judith

2013-01-01

This is a report of the results of a pilot project conducted to identify the areas where role confusion/ambiguity exists in the practice of nurse case management. A convenience sample of 25 registered nurses practicing as case managers in a small east coast medical treatment facility's outpatient clinics. Participants responded to 2 Likert-type surveys designed to evaluate role confusion from an individual and a team membership perspective. Analysis indicated that nurse case managers experience role confusion in the specific areas of conflicts between time resources, capabilities, and multiple individual roles. There was no identified role confusion associated with membership on multidisciplinary teams. The application of the Synergy Model as a theoretical framework for nurse case management serves as a benchmark for the implementation of evidence-based practices. This project could serve as the starting point for the development of a skill set for nurse case managers, for the standardization of the practice, and for the recognition of nurse case management as a legitimate nursing subspecialty.

Body Dissatisfaction in Women Across the Lifespan: Results of the UNC-SELF and Gender and Body Image (GABI) Studies

PubMed Central

Runfola, Cristin D.; Von Holle, Ann; Trace, Sara E.; Brownley, Kimberly A.; Hofmeier, Sara M.; Gagne, Danielle A.; Bulik, Cynthia M.

2013-01-01

To explore age differences in current and preferred silhouette and body dissatisfaction (current -preferred silhouette discrepancy) in women aged 25-89 years using figural stimuli (range: 1-very small to 9-very large). Data were abstracted from two online convenience samples (N = 5,868). t-tests with permutation-adjusted p-values examined linear associations between mean silhouette scores (current, preferred, discrepancy score) and age with/without stratification by body mass index (BMI). Modal current silhouette was 5; modal preferred silhouette was 4; mean discrepancy score was 1.8. There was no significant association between current silhouette and age, but a positive linear association between preferred silhouette and age remained after stratification by BMI. A significant inverse linear association of silhouette discrepancy score and age was found only prior to stratification by BMI. Body dissatisfaction exists in women across the adult life span and is influenced by BMI. PMID:22949165

Construct validity of the Moral Development Scale for Professionals (MDSP)

PubMed Central

Söderhamn, Olle; Bjørnestad, John Olav; Skisland, Anne; Cliffordson, Christina

2011-01-01

The aim of this study was to investigate the construct validity of the Moral Development Scale for Professionals (MDSP) using structural equation modeling. The instrument is a 12-item self-report instrument, developed in the Scandinavian cultural context and based on Kohlberg’s theory. A hypothesized simplex structure model underlying the MDSP was tested through structural equation modeling. Validity was also tested as the proportion of respondents older than 20 years that reached the highest moral level, which according to the theory should be small. A convenience sample of 339 nursing students with a mean age of 25.3 years participated. Results confirmed the simplex model structure, indicating that MDSP reflects a moral construct empirically organized from low to high. A minority of respondents >20 years of age (13.5%) scored more than 80% on the highest moral level. The findings support the construct validity of the MDSP and the stages and levels in Kohlberg’s theory. PMID:21655343

Blood cell mRNAs and microRNAs: optimized protocols for extraction and preservation.

PubMed

Eikmans, Michael; Rekers, Niels V; Anholts, Jacqueline D H; Heidt, Sebastiaan; Claas, Frans H J

2013-03-14

Assessing messenger RNA (mRNA) and microRNA levels in peripheral blood cells may complement conventional parameters in clinical practice. Working with small, precious samples requires optimal RNA yields and minimal RNA degradation. Several procedures for RNA extraction and complementary DNA (cDNA) synthesis were compared for their efficiency. The effect on RNA quality of freeze-thawing peripheral blood cells and storage in preserving reagents was investigated. In terms of RNA yield and convenience, quality quantitative polymerase chain reaction signals per nanogram of total RNA and using NucleoSpin and mirVana columns is preferable. The SuperScript III protocol results in the highest cDNA yields. During conventional procedures of storing peripheral blood cells at -180°C and thawing them thereafter, RNA integrity is maintained. TRIzol preserves RNA in cells stored at -20°C. Detection of mRNA levels significantly decreases in degraded RNA samples, whereas microRNA molecules remain relatively stable. When standardized to reference targets, mRNA transcripts and microRNAs can be reliably quantified in moderately degraded (quality index 4-7) and severely degraded (quality index <4) RNA samples, respectively. We describe a strategy for obtaining high-quality and quantity RNA from fresh and stored cells from blood. The results serve as a guideline for sensitive mRNA and microRNA expression assessment in clinical material.

Self-reported heart disease among Arab and Chaldean American women residing in southeast Michigan.

PubMed

Jamil, Hikmet; Fakhouri, Monty; Dallo, Florence; Templin, Thomas; Khoury, Radwan; Fakhouri, Haifa

2008-01-01

This study estimates the prevalence of heart disease among Arab and Chaldean American women and examines the association between Arab and Chaldean ethnicity and heart disease among a sample of women. This was a cross-sectional study of a convenience sample of 2084 Arab, Chaldean, and African American women aged > or = 18 years who completed a survey that was distributed at churches, mosques, and small businesses in southeast Michigans. Logistic regression was used to estimate odds ratios and 95% confidence intervals for the association between ethnicity and self-reported heart disease before and after adjusting for demographic, socioeconomic status, health care, chronic conditions, and health behavior variables. A sample of 2084 Arab, Chaldean, and African American women 18 years of age and older. The overall prevalence of heart disease was 5.1%. Estimates were higher for Arabs (7.1%), lower for Chaldeans (6.6%), and lowest among African Americans (1.8%). In the unadjusted model, Chaldeans and Arabs were four times more likely to have heart disease than were African Americans. However, in the fully adjusted model, the association between Chaldean or Arab ethnicity and heart disease was no longer statistically significant. Arab or Chaldean ethnicity was not significantly associated with self-reported heart disease among women, which suggests that other factors account for this relationship. Future studies should collect more detailed socioeconomic status, acculturation, and health behavior information.

How Common is Men's Self-Reported Sexual Interest in Prepubescent Children?

PubMed

Dombert, Beate; Schmidt, Alexander F; Banse, Rainer; Briken, Peer; Hoyer, Jürgen; Neutze, Janina; Osterheider, Michael

2016-01-01

Consistent evidence exists for sexual interest in children in nonclinical/nonforensic male populations. However, prevalences for community men's self-reported sexual interest in children have been based on indiscriminate definitions including postpubescent individuals, age-restricted samples, and/or small convenience samples. The present research assessed men's self-reported sexual interest in children (including child prostitution and child sex tourism) on the community level and examined the link between strictly defined sexual fantasies and behaviors involving prepubescent children. In an online survey of 8,718 German men, 4.1% reported sexual fantasies involving prepubescent children, 3.2% reported sexual offending against prepubescent children, and 0.1% reported a pedophilic sexual preference. Sexual fantasies involving prepubescent children were positively related to sexual offending against prepubescent children. Sexual interest in children was associated with subjectively perceived need for therapeutic help. In contrast to findings from forensic samples, men who reported child pornography use exclusively were identified as a subgroup differing from contact sexual offenders against prepubescent children and men who reported both child pornography use and contact sexual offenses against prepubescent children. The empirical link between child-related sexual fantasies and sexual victimization of prepubescent children and high levels of subjective distress from this inclination underscore the importance of evidence-based child sexual abuse prevention approaches in the community. Findings are discussed in terms of their relation to pedophilic disorder.

Autonomic function in manganese alloy workers

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

Barrington, W.W.; Angle, C.R.; Willcockson, N.K.

1998-07-01

The observation of orthostatic hypotension in an index case of manganese toxicity lead to this prospective attempt to evaluate cardiovascular autonomic function and cognitive and emotional neurotoxicity in eight manganese alloy welders and machinists. The subjects consisted of a convenience sample consisting of an index case of manganese dementia, his four co-workers in a frog shop for gouging, welding, and grinding repair of high manganese railway track and a convenience sample of three mild steel welders with lesser manganese exposure also referred because of cognitive or autonomic symptoms. Frog shop air manganese samples 9.6--10 years before and 1.2--3.4 years aftermore » the diagnosis of the index case exceeded 1.0 mg/m{sup 3} in 29% and 0.2 mg/m{sup 3} in 62%. Twenty-four-hour electrocardiographic (Holter) monitoring was used to determine the temporal variability of the heartrate (RR{prime} interval) and the rates of change at low frequency and high frequency. MMPI and MCMI personality assessment and short-term memory, figure copy, controlled oral word association, and symbol digit tests were used.« less

Misbeliefs About Gambling in a Convenience Sample from the General Population.

PubMed

Tomei, Alexander; Bamert, Anthony; Sani, Anna-Maria

2017-09-01

We examined knowledge about the role of randomness in gambling and the principle of independence of events, in a community sample. We also investigated whether this knowledge varies according to gender and age. A convenience sample of 1257 residents in French-speaking Switzerland, aged 18-88 years (28.5% of women) completed a short online questionnaire. This assessed the perceived role of human skills in four different games as well as beliefs relating to the principle of independence of events. The results show that 19.5% of the respondents perceived Roulette as a game for which the outcome is determined by skill. They also showed that 15.1% of the respondents did not hold beliefs about the independence of events principle. Gender and age differences were also observed: Men were proportionally more likely to hold erroneous beliefs about gambling skills and the independence of events, compared to women. The 18-25 year-old age group attributed Roulette outcomes to the gambler's skill more frequently than the older categories. The implications of these findings for prevention and social support are discussed.

Colorimetric DNAzyme Biosensor for Convenience Detection of Enterotoxin B Harboring Staphylococcus aureus from Food Samples.

PubMed

Mondal, Bhairab; N, Bhavanashri; Ramlal, Shylaja; Kingston, Joseph

2018-02-14

In the present study, a colorimetric DNAzymes biosensor strategy was devised in combination with immunomagnetic separation for rapid and easy detection of enterotoxin B harboring Staphylococcus aureus from food and clinical samples. The method employs immunocapture of S. aureus and amplification of seb gene by DNAzyme complementary sequence integrated forward primer and with specific reverse primer. The DNAzyme sequence integrated dsDNA PCR products when treated with hemin and TMB (3,3',5,5'-tetramethylbenzidine) in the presence of H 2 O 2 produce colorimetric signal. A linear relationship of optical signal with the initial template of seb was obtained which could be monitored by visually or spectrophotrometrically for qualitative and quantitative detection. The limit of detection for the assay was approximately 10 2 CFU/mL of seb gene harboring target. This method is convenient compared to gel based and ELISA systems. Further, spiking studies and analysis on natural samples emphasized the robustness and applicability of developed method. Altogether, the established assay could be a reliable alternative, low-cost, viable detection tool for the routine investigation of seb from food and clinical sources.

How Hot Can a Fire Piston Get?

ERIC Educational Resources Information Center

Scott-Brown, J. A.; Cunningham, O. A.; Goad, B. C.

2010-01-01

The fire piston is just a sealed syringe containing a small amount of tinder. When the plunger is forced downwards, the air inside is compressed and heats up, setting fire to the tinder. It has been used as a convenient and portable way of starting fires "over a wide area from northern Burma and Siam through the Malay Peninsula and the Malayan…

High Temperature Silicon Carbide (SiC) Traction Motor Drive

DTIC Science & Technology

2011-08-09

UNCLASSIFIED Distribution Statement A. Approved for public release; distribution is unlimited. UNCLASSIFIED HIGH TEMPERATURE SILICON CARBIDE...be modular and conveniently distributed. Small component size and operation with high - temperature liquid coolant are essential factors in the...these densities, power modules capable of high - temperature operation were developed using SiC normally-off JFETs. This paper will discuss the unique

Synthesizing a Berberine Derivative and Evaluating Antimicrobial Activity to Reinforce with Students the Potential Significance of Small Chemical Structure Changes for Biological Systems

ERIC Educational Resources Information Center

Rodrigues, Catarina A. B.; Neto, Iris; Rijo, Patricia; Afonso, Carlos A. M.

2018-01-01

The convenient synthesis of dihydroberberine by the reduction of berberine is described as an experiment for an upper-division undergraduate organic chemistry laboratory course. Students obtained up to 74% yield of the desired pure product without the use of chromatographic techniques. The antimicrobial activities of both compounds against…

Convenience and Community? An Exploratory Investigation into Learners' Experiences of Web Conferencing

ERIC Educational Resources Information Center

Cornelius, Sarah

2013-01-01

This paper presents the findings of an exploratory study into the experiences of a small group of learners who have made extensive use of web conferencing as part of their studies over the academic year 2009/10. The paper outlines the design of the programme and structure of web conferencing workshops. It draws on findings from a post-programme…

Retailer-Led Sugar-Sweetened Beverage Price Increase Reduces Purchases in a Hospital Convenience Store in Melbourne, Australia: A Mixed Methods Evaluation.

PubMed

Blake, Miranda R; Peeters, Anna; Lancsar, Emily; Boelsen-Robinson, Tara; Corben, Kirstan; Stevenson, Christopher E; Palermo, Claire; Backholer, Kathryn

2018-06-01

Limited evidence has been gathered on the real-world impact of sugar-sweetened beverage price changes on purchasing behavior over time or in community-retail settings. Our aim was to determine changes in beverage purchases, business outcomes, and customer and retailer satisfaction associated with a retailer-led sugar-sweetened beverage price increase in a convenience store. We hypothesized that purchases of less-healthy beverages would decrease compared to predicted sales. A convergent parallel mixed methods design complemented sales data (122 weeks pre-intervention, 17 weeks during intervention) with stakeholder interviews and customer surveys. Electronic beverage sales data were collected from a convenience store in Melbourne, Australia (August through November 2015). Convenience store staff completed semi-structured interviews (n=4) and adult customers exiting the store completed surveys (n=352). Beverages were classified using a state government framework. Prices of "red" beverages (eg, nondiet soft drinks, energy drinks) increased by 20%. Prices of "amber" (eg, diet soft drinks, small pure fruit juices) and "green" beverages (eg, water) were unchanged. Changes in beverage volume, item sales, and revenue during the intervention were compared with predicted sales. Sales data were analyzed using time series segmented regression while controlling for pre-intervention trends, autocorrelation in sales data, and seasonal fluctuations. Beverage volume sales of red (-27.6%; 95% CI -32.2 to -23.0) and amber (-26.7%; 95% CI -39.3 to -16.0) decreased, and volume of green beverages increased (+26.9%; 95% CI +14.1 to +39.7) in the 17th intervention week compared with predicted sales. Store manager and staff considered the intervention business-neutral, despite a small reduction in beverage revenue. Fifteen percent of customers noticed the price difference and 61% supported the intervention. A 20% sugar-sweetened beverage price increase was associated with a reduction in their purchases and an increase in purchases of healthier alternatives. Community retail settings present a bottom-up approach to improving consumer beverage choices. Copyright © 2018 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Development of a Web-based educational intervention to improve cross-cultural communication among hospice providers

PubMed Central

DOORENBOS, ARDITH Z.; LINDHORST, TARYN; SCHIM, STEPHANIE MYERS; VAN SCHAIK, EILEEN; DEMIRIS, GEORGE; WECHKIN, HOPE A.; CURTIS, J. RANDALL

2010-01-01

This paper describes the theoretical foundation, development, and content of a Web-based educational intervention to improve cross-cultural communication about end-of-life concerns and reports on the preliminary evaluation of this intervention using a qualitative study design. The data were collected with non-structured questions in a convenience sample of 21 hospice providers. Participants reported that they found the training appropriate and useful. Participants also reported finding the online delivery convenient and the interactive format valuable. Improving the quality of cross-cultural patient–provider communication can contribute to reducing disparities at end-of-life. PMID:21132601

Convenient optical pressure gauge for multimegabar pressures calibrated to 300 GPa

NASA Astrophysics Data System (ADS)

Sun, Liling; Ruoff, Arthur L.; Stupian, Gary

2005-01-01

The accurate measurement of pressure by a straightforward and inexpensive optical procedure has been needed in the multimegabar region since static pressures over 216GPa, 361GPa, 420GPa and 560GPa were obtained in the diamond anvil cell. Here, a simple optical pressure gauge based on the Raman shift of the diamond at the center of a diamond tip at the diamond-sample interface is calibrated against a primary gauge (Pt isotherm at 300K from shock data) to 300GPa, thus enabling researchers who do not have a synchrotron to conveniently measure pressure with an optical scale from 50to300GPa.

A comparison of four sampling methods among men having sex with men in China: implications for HIV/STD surveillance and prevention

PubMed Central

Guo, Yan; Li, Xiaoming; Fang, Xiaoyi; Lin, Xiuyun; Song, Yan; Jiang, Shuling; Stanton, Bonita

2011-01-01

Sample representativeness remains one of the challenges in effective HIV/STD surveillance and prevention targeting MSM worldwide. Although convenience samples are widely used in studies of MSM, previous studies suggested that these samples might not be representative of the broader MSM population. This issue becomes even more critical in many developing countries where needed resources for conducting probability sampling are limited. We examined variations in HIV and Syphilis infections and sociodemographic and behavioral factors among 307 young migrant MSM recruited using four different convenience sampling methods (peer outreach, informal social network, Internet, and venue-based) in Beijing, China in 2009. The participants completed a self-administered survey and provided blood specimens for HIV/STD testing. Among the four MSM samples using different recruitment methods, rates of HIV infections were 5.1%, 5.8%, 7.8%, and 3.4%; rates of Syphilis infection were 21.8%, 36.2%, 11.8%, and 13.8%; rates of inconsistent condom use were 57%, 52%, 58%, and 38%. Significant differences were found in various sociodemographic characteristics (e.g., age, migration history, education, income, places of employment) and risk behaviors (e.g., age at first sex, number of sex partners, involvement in commercial sex, and substance use) among samples recruited by different sampling methods. The results confirmed the challenges of obtaining representative MSM samples and underscored the importance of using multiple sampling methods to reach MSM from diverse backgrounds and in different social segments and to improve the representativeness of the MSM samples when the use of probability sampling approach is not feasible. PMID:21711162

A comparison of four sampling methods among men having sex with men in China: implications for HIV/STD surveillance and prevention.

PubMed

Guo, Yan; Li, Xiaoming; Fang, Xiaoyi; Lin, Xiuyun; Song, Yan; Jiang, Shuling; Stanton, Bonita

2011-11-01

Sample representativeness remains one of the challenges in effective HIV/STD surveillance and prevention targeting men who have sex with men (MSM) worldwide. Although convenience samples are widely used in studies of MSM, previous studies suggested that these samples might not be representative of the broader MSM population. This issue becomes even more critical in many developing countries where needed resources for conducting probability sampling are limited. We examined variations in HIV and Syphilis infections and sociodemographic and behavioral factors among 307 young migrant MSM recruited using four different convenience sampling methods (peer outreach, informal social network, Internet, and venue-based) in Beijing, China in 2009. The participants completed a self-administered survey and provided blood specimens for HIV/STD testing. Among the four MSM samples using different recruitment methods, rates of HIV infections were 5.1%, 5.8%, 7.8%, and 3.4%; rates of Syphilis infection were 21.8%, 36.2%, 11.8%, and 13.8%; and rates of inconsistent condom use were 57%, 52%, 58%, and 38%. Significant differences were found in various sociodemographic characteristics (e.g., age, migration history, education, income, and places of employment) and risk behaviors (e.g., age at first sex, number of sex partners, involvement in commercial sex, and substance use) among samples recruited by different sampling methods. The results confirmed the challenges of obtaining representative MSM samples and underscored the importance of using multiple sampling methods to reach MSM from diverse backgrounds and in different social segments and to improve the representativeness of the MSM samples when the use of probability sampling approach is not feasible.

Electrolyte solutions at curved electrodes. I. Mesoscopic approach

NASA Astrophysics Data System (ADS)

Reindl, Andreas; Bier, Markus; Dietrich, S.

2017-04-01

Within the Poisson-Boltzmann approach, electrolytes in contact with planar, spherical, and cylindrical electrodes are analyzed systematically. The dependences of their capacitance C on the surface charge density σ and the ionic strength I are examined as a function of the wall curvature. The surface charge density has a strong effect on the capacitance for small curvatures, whereas for large curvatures the behavior becomes independent of σ. An expansion for small curvatures gives rise to capacitance coefficients which depend only on a single parameter, allowing for a convenient analysis. The universal behavior at large curvatures can be captured by an analytic expression.

Manufacturing Methods and Technology Project Summary Reports

DTIC Science & Technology

1984-12-01

are used. The instrument chosen provides a convenient method of artifically aging a propellant sample while automatically analyzing for evolved oxides...and aging . Shortly after the engineering sample run, a change in REMBASS require- ments eliminated the crystal high shock requirements. This resulted...material with minimum outgassing in a precision vacuum QXFF. Minimal outgas- ..- sing reduces aging in the finished unit. A fixture was also developed to

A Comparison of the Social Competence of Children with Moderate Intellectual Disability in Inclusive versus Segregated School Settings

ERIC Educational Resources Information Center

Hardiman, Sharon; Guerin, Suzanne; Fitzsimons, Elaine

2009-01-01

This is the first study to compare the social competence of children with moderate intellectual disability in inclusive versus segregated school settings in the Republic of Ireland. A convenience sample was recruited through two large ID services. The sample comprised 45 children across two groups: Group 1 (n = 20; inclusive school) and Group 2 (n…

Private Universities in Kenya Seek Alternative Ways to Manage Change in Teacher Education Curriculum in Compliance with the Commission for University Education Reforms

ERIC Educational Resources Information Center

Amimo, Catherine Adhiambo

2016-01-01

This study investigated management of change in teacher education curriculum in Private universities in Kenya. The study employed a concurrent mixed methods design that is based on the use of both quantitative and qualitative approaches. A multi-stage sampling process which included purposive, convenience, cluster, and snowball sampling methods…

Streamlined sample cleanup using combined dispersive solid-phase extraction and in-vial filtration for analysis of pesticides and environmental pollutants in shrimp

USDA-ARS?s Scientific Manuscript database

A new method of sample preparation was developed and is reported for the first time. The approach combines in-vial filtration with dispersive solid-phase extraction (d-SPE) in a fast and convenient cleanup of QuEChERS (quick, easy, cheap, effective, rugged, and safe) extracts. The method was appli...

Impact of the School Outreach Tour Program of Citizens Archive of Pakistan on Students' Perceptions and Attitudes

ERIC Educational Resources Information Center

Alam, Qutbi

2017-01-01

This paper examines the impact of School Outreach Tour (SOT-A) program,one of the projects of the Citizens Archive of Pakistan (CAP), a non-profit organisation on the perceptions and attitudes of Grade-8 Students of partners' schools. The sample in this study consists of (n = 139) students of Grade-8, selected by convenience sampling from five…

The Association between Body Dissatisfaction and Depression: An Examination of the Moderating Effects of Gender, Age, and Weight Status in a Sample of Chinese Adolescents

ERIC Educational Resources Information Center

Chen, Gui; Guo, Guiping; Gong, Jingbo; Xiao, Shuiyuan

2015-01-01

The current study investigated the moderating effects of gender, age, and weight status on the relationship between body dissatisfaction and depression among adolescents. Data were collected on body dissatisfaction, depression, and demographic characteristics from a convenience sample of 1,101 adolescents (505 girls, 596 boys). The relationship…

MicroRNA Biomarkers of Toxicity in Biological Matrices

EPA Science Inventory

Biomarker measurements that reliably correlate with tissue injury and can be measured from sampling accessible biofluids offer enormous benefits in terms of cost, time, and convenience when assessing environmental and drug-induced toxicity in model systems or human cohorts. Micro...

76 FR 23302 - Certain Steel Wheels From the People's Republic of China: Initiation of Countervailing Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-26

... sampling method to poll the industry. Section 771(4)(A) of the Act defines the ``industry'' as the.... These HTSUS numbers are provided for convenience and customs purposes only; the written description of...

Convenient mounting method for electrical measurements of thin samples

NASA Technical Reports Server (NTRS)

Matus, L. G.; Summers, R. L.

1986-01-01

A method for mounting thin samples for electrical measurements is described. The technique is based on a vacuum chuck concept in which the vacuum chuck simultaneously holds the sample and established electrical contact. The mounting plate is composed of a glass-ceramic insulating material and the surfaces of the plate and vacuum chuck are polished. The operation of the vacuum chuck is examined. The contacts on the sample and mounting plate, which are sputter-deposited through metal masks, are analyzed. The mounting method was utilized for van der Pauw measurements.

Food safety issues and training methods for ready-to-eat foods in the grocery industry.

PubMed

Binkley, Margaret; Ghiselli, Richard

2005-10-01

As Americans have become more pressed for time, the use of convenient, simplified meals become a way of life. One aspect of this trend, known as Home Meal Replacement (IIMR), has increased in sales since its inception. Between 1999 and 2001, the average annual expenditure per consumer rose 5.6 pereent, and $958 per person per year was spent in 2002. Along with this growth, food safety risks may have increased. The study reported here examined efforts being undertaken by grocery and convenience stores to control the wholesomeness of INR food items. After a convenience sample of 500 grocery store executives was identified, a 32-item questionnaire was developed and mailed to the executives. The results indicate that the industry has taken food safety seriously with only 10 pereent reporting that they have no food safety training. The executives cited employee turnover as a major concern in food safety today, along with lack of food safety knowledge of the consumer and improper holding temperatures.

A convenient method of obtaining percentile norms and accompanying interval estimates for self-report mood scales (DASS, DASS-21, HADS, PANAS, and sAD).

PubMed

Crawford, John R; Garthwaite, Paul H; Lawrie, Caroline J; Henry, Julie D; MacDonald, Marie A; Sutherland, Jane; Sinha, Priyanka

2009-06-01

A series of recent papers have reported normative data from the general adult population for commonly used self-report mood scales. To bring together and supplement these data in order to provide a convenient means of obtaining percentile norms for the mood scales. A computer program was developed that provides point and interval estimates of the percentile rank corresponding to raw scores on the various self-report scales. The program can be used to obtain point and interval estimates of the percentile rank of an individual's raw scores on the DASS, DASS-21, HADS, PANAS, and sAD mood scales, based on normative sample sizes ranging from 758 to 3822. The interval estimates can be obtained using either classical or Bayesian methods as preferred. The computer program (which can be downloaded at www.abdn.ac.uk/~psy086/dept/MoodScore.htm) provides a convenient and reliable means of supplementing existing cut-off scores for self-report mood scales.

Touch And Go Camera System (TAGCAMS) for the OSIRIS-REx Asteroid Sample Return Mission

NASA Astrophysics Data System (ADS)

Bos, B. J.; Ravine, M. A.; Caplinger, M.; Schaffner, J. A.; Ladewig, J. V.; Olds, R. D.; Norman, C. D.; Huish, D.; Hughes, M.; Anderson, S. K.; Lorenz, D. A.; May, A.; Jackman, C. D.; Nelson, D.; Moreau, M.; Kubitschek, D.; Getzandanner, K.; Gordon, K. E.; Eberhardt, A.; Lauretta, D. S.

2018-02-01

NASA's OSIRIS-REx asteroid sample return mission spacecraft includes the Touch And Go Camera System (TAGCAMS) three camera-head instrument. The purpose of TAGCAMS is to provide imagery during the mission to facilitate navigation to the target asteroid, confirm acquisition of the asteroid sample, and document asteroid sample stowage. The cameras were designed and constructed by Malin Space Science Systems (MSSS) based on requirements developed by Lockheed Martin and NASA. All three of the cameras are mounted to the spacecraft nadir deck and provide images in the visible part of the spectrum, 400-700 nm. Two of the TAGCAMS cameras, NavCam 1 and NavCam 2, serve as fully redundant navigation cameras to support optical navigation and natural feature tracking. Their boresights are aligned in the nadir direction with small angular offsets for operational convenience. The third TAGCAMS camera, StowCam, provides imagery to assist with and confirm proper stowage of the asteroid sample. Its boresight is pointed at the OSIRIS-REx sample return capsule located on the spacecraft deck. All three cameras have at their heart a 2592 × 1944 pixel complementary metal oxide semiconductor (CMOS) detector array that provides up to 12-bit pixel depth. All cameras also share the same lens design and a camera field of view of roughly 44° × 32° with a pixel scale of 0.28 mrad/pixel. The StowCam lens is focused to image features on the spacecraft deck, while both NavCam lens focus positions are optimized for imaging at infinity. A brief description of the TAGCAMS instrument and how it is used to support critical OSIRIS-REx operations is provided.

Glyphosate in Irish adults - A pilot study in 2017.

PubMed

Connolly, Alison; Leahy, Michelle; Jones, Kate; Kenny, Laura; Coggins, Marie A

2018-08-01

Glyphosate is the highest volume herbicide used globally and has recently been classified as a 2 A 'probably carcinogenic to humans' by the International Agency for Research on Cancer (IARC). There is limited data to evaluate the public health impacts from glyphosate exposure. The objective of this study is to conduct an exploratory glyphosate exposure assessment study among Irish adults, who were non-occupational users of glyphosate. A convenient sampling method was used, collecting one first morning void spot urine sample from each participant. A biomonitoring survey involving the collection and analysis of 20 ml spot urine samples from 50 Irish adults was conducted in June 2017. Participants completed a short questionnaire to collect information on demographics, dietary habits and lifestyle. Glyphosate was extracted using solid phase extraction (SPE) and analysed by liquid chromatography tandem mass spectrometry (LC-MC/MS). Of the 50 urine samples analysed, 10 (20%) contained detectable levels of glyphosate (0.80-1.35 µg L -1 ). Exposure concentrations are higher than those reported in comparable studies of European and American adults. Glyphosate was detectable in 20% of the samples collected from Irish adults. The low proportion of detectable glyphosate levels could be due to lower localised use of pesticides, having a small sample size or the higher analytical detection limit used in this study (0.5 µg L -1 ), which could underestimate the true exposure and warrants further investigation. Given the widespread use of glyphosate, further information on population exposure is required to advance our understanding of the relationship between chronic low dose exposure to glyphosate and human health risk. Copyright © 2018 Elsevier Inc. All rights reserved.

Further development of a robust workup process for solution-phase high-throughput library synthesis to address environmental and sample tracking issues.

PubMed

Kuroda, Noritaka; Hird, Nick; Cork, David G

2006-01-01

During further improvement of a high-throughput, solution-phase synthesis system, new workup tools and apparatus for parallel liquid-liquid extraction and evaporation have been developed. A combination of in-house design and collaboration with external manufacturers has been used to address (1) environmental issues concerning solvent emissions and (2) sample tracking errors arising from manual intervention. A parallel liquid-liquid extraction unit, containing miniature high-speed magnetic stirrers for efficient mixing of organic and aqueous phases, has been developed for use on a multichannel liquid handler. Separation of the phases is achieved by dispensing them into a newly patented filter tube containing a vertical hydrophobic porous membrane, which allows only the organic phase to pass into collection vials positioned below. The vertical positioning of the membrane overcomes the hitherto dependence on the use of heavier-than-water, bottom-phase, organic solvents such as dichloromethane, which are restricted due to environmental concerns. Both small (6-mL) and large (60-mL) filter tubes were developed for parallel phase separation in library and template synthesis, respectively. In addition, an apparatus for parallel solvent evaporation was developed to (1) remove solvent from the above samples with highly efficient recovery and (2) avoid the movement of individual samples between their collection on a liquid handler and registration to prevent sample identification errors. The apparatus uses a diaphragm pump to achieve a dynamic circulating closed system with a heating block for the rack of 96 sample vials and an efficient condenser to trap the solvents. Solvent recovery is typically >98%, and convenient operation and monitoring has made the apparatus the first choice for removal of volatile solvents.

Analysis of phytoplankton distribution and community structure in the German Bight with respect to the different size classes

NASA Astrophysics Data System (ADS)

Wollschläger, Jochen; Wiltshire, Karen Helen; Petersen, Wilhelm; Metfies, Katja

2015-05-01

Investigation of phytoplankton biodiversity, ecology, and biogeography is crucial for understanding marine ecosystems. Research is often carried out on the basis of microscopic observations, but due to the limitations of this approach regarding detection and identification of picophytoplankton (0.2-2 μm) and nanophytoplankton (2-20 μm), these investigations are mainly focused on the microphytoplankton (20-200 μm). In the last decades, various methods based on optical and molecular biological approaches have evolved which enable a more rapid and convenient analysis of phytoplankton samples and a more detailed assessment of small phytoplankton. In this study, a selection of these methods (in situ fluorescence, flow cytometry, genetic fingerprinting, and DNA microarray) was placed in complement to light microscopy and HPLC-based pigment analysis to investigate both biomass distribution and community structure of phytoplankton. As far as possible, the size classes were analyzed separately. Investigations were carried out on six cruises in the German Bight in 2010 and 2011 to analyze both spatial and seasonal variability. Microphytoplankton was identified as the major contributor to biomass in all seasons, followed by the nanophytoplankton. Generally, biomass distribution was patchy, but the overall contribution of small phytoplankton was higher in offshore areas and also in areas exhibiting higher turbidity. Regarding temporal development of the community, differences between the small phytoplankton community and the microphytoplankton were found. The latter exhibited a seasonal pattern regarding number of taxa present, alpha- and beta-diversity, and community structure, while for the nano- and especially the picophytoplankton, a general shift in the community between both years was observable without seasonality. Although the reason for this shift remains unclear, the results imply a different response of large and small phytoplankton to environmental influences.

Food Choice Motives When Purchasing in Organic and Conventional Consumer Clusters: Focus on Sustainable Concerns (The NutriNet-Santé Cohort Study).

PubMed

Baudry, Julia; Péneau, Sandrine; Allès, Benjamin; Touvier, Mathilde; Hercberg, Serge; Galan, Pilar; Amiot, Marie-Josèphe; Lairon, Denis; Méjean, Caroline; Kesse-Guyot, Emmanuelle

2017-01-24

The purpose of this study was to examine food choice motives associated with various organic and conventional dietary patterns among 22,366 participants of the NutriNet-Santé study. Dietary intakes were estimated using a food frequency questionnaire. Food choice motives were assessed using a validated 63-item-questionnaire gathered into nine food choice motive dimension scores: "absence of contaminants", "avoidance for environmental reasons", "ethics and environment", "taste", "innovation", "local and traditional production", "price", "health" and "convenience". Five consumers' clusters were identified: "standard conventional food small eaters", "unhealthy conventional food big eaters", "standard organic food small eaters", "green organic food eaters" and "hedonist moderate organic food eaters". Relationships between food choice motive dimension scores and consumers' clusters were assessed using analysis of covariance (ANCOVA) models adjusted for sociodemographic factors. "Green organic food eaters" had the highest mean score for the "health" dimension, while "unhealthy conventional food big eaters" obtained the lowest mean score for the "absence of contaminants" dimension. "Standard organic food small eaters", "green organic food eaters" and "hedonist moderate organic food eaters" had comparable scores for the "taste" dimension. "Unhealthy conventional food big eaters" had the highest mean score for the "price" dimension while "green organic food eaters" had the lowest mean scores for the "innovation" and "convenience" dimensions. These results provide new insights into the food choice motives of diverse consumers' profiles including "green" and "hedonist" eaters.

Biotechnology

NASA Image and Video Library

2002-07-31

Renal stones are never convenient, but they are a particular concern for astronauts who have limited access to treatment during flight. Researchers are examining how earthbound preventions for renal stone formation work in flight, ensuring missions are not ended prematurely due to this medical condition. The micrograph shows calcium oxalate crystals in urine. These small crystals can develop to form renal stones. Principal Investigator: Dr. Peggy Whitson, NASA Johnson Space Center, Houston, TX.

Fiber-optics couple arthroscope to TV

NASA Technical Reports Server (NTRS)

Franke, J. M.; Rhodes, D. B.

1981-01-01

Convenient, hand-held coupler images output of arthroscope onto coherent fiber bundle. Arthroscope allows surgeons to examine internal organs through any small opening in body. Coupler is also used for engine inspection, instrument repair, and around-corner visual inspection. Image from arthroscope travels along flexible bundle and appears at other cable end where it is recollimated by lens. Image is read from lens or projected on color TV camera.

A motor-driven syringe-type gradient maker for forming immobilized pH gradient gels.

PubMed

Fawcett, J S; Sullivan, J V; Chidakel, B E; Chrambach, A

1988-05-01

A motor driven gradient maker based on the commercial model (Jule Inc., Trumbull, CT) was designed for immobilized pH gradient gels to provide small volumes, rapid stirring and delivery, strict volume and temperature control and air exclusion. The device was constructed and by a convenient procedure yields highly reproducible gradients either in solution or on polyacrylamide gels.

Photocatalytic efficiency of CdS film synthesized by CBD method

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

Ishiyama, T.; Sato, Y.; Jeyadevan, B.

2006-05-15

Cadmium Sulfide semiconductor has comparatively small band gap and act as photocatalyst under irradiation of visible light. For practical use, it is convenient to fix the photocatalyst on a substrate as a thin film. In this study, we prepared CdS thin film on Ti substrate by Chemical Bath Deposition (CBD). To improve photocatalytic activity, CdS film was annealed and optimum thickness was investigated.

Small-Scale Production of High-Density Dry Ice: A Variant Combination of Two Classic Demonstrations

ERIC Educational Resources Information Center

Flowers, Paul A.

2009-01-01

Easily recoverable, thumb-sized pieces of high-density dry ice are conveniently produced by deposition of carbon dioxide within a test tube submerged in liquid nitrogen. A carbon dioxide-filled balloon sealed over the mouth of the test tube serves as a gas reservoir, and further permits a dramatic demonstration of both the gas-to-solid phase…

Creativity, Religiosity, and Political Attitudes

ERIC Educational Resources Information Center

Zysberg, Leehu; Schenk, Tal

2013-01-01

Although theoretically proposed in the literature, the direct associations between political attitudes, religion, and creativity have been scarcely explored. A convenience sample of 123 adults working in Israel filled out questionnaires assessing political-social attitudes, religiosity, and background factors (e.g., age, gender, education, and…

Assessing Environmental Stewardship Motivation

ERIC Educational Resources Information Center

Bramston, Paul; Pretty, Grace; Zammit, Charlie

2011-01-01

Environmental stewardship networks flourish across Australia. Although the environment benefits, this article looks to identify what volunteers draw from their stewardship. The authors adapted 16 questions that purportedly tap environmental stewardship motivation and administered them to a convenience sample of 318 university students and then to…

Feasibility of online nutrition education in the workplace: Working Toward Healthy Lifestyles

USDA-ARS?s Scientific Manuscript database

Objective: Determination of feasibility of online nutrition education in the federal workplace. Design: Pre-test/post-test pilot study with data collection occurring from September to December 2016. Setting: Two United States Department of Agriculture workplaces. Participants: Convenience sample ...

Exploring the acceptability of human papillomavirus self-sampling among Muslim immigrant women.

PubMed

Lofters, Aisha K; Vahabi, Mandana; Fardad, Mitra; Raza, Afrah

2017-01-01

With appropriate screening (ie, the Papanicolaou [Pap] test), cervical cancer is highly preventable, and high-income countries, including Canada, have observed significant decreases in cervical cancer mortality. However, certain subgroups, including immigrants from countries with large Muslim populations, experience disparities in cervical cancer screening. Little is known about the acceptability of human papillomavirus (HPV) self-sampling as a screening strategy among Muslim immigrant women in Canada. This study assessed cervical cancer screening practices, knowledge and attitudes, and acceptability of HPV self-sampling among Muslim immigrant women. A convenience sample of 30 women was recruited over a 3-month period (June-August 2015) in the Greater Toronto Area. All women were between 21 and 69 years old, foreign-born, and self-identified as Muslim, and had good knowledge of English. Data were collected through a self-completed questionnaire. More than half of the participants falsely indicated that Pap tests may cause cervical infection, and 46.7% indicated that the test is an intrusion on privacy. The majority of women reported that they would be willing to try HPV self-sampling, and more than half would prefer this method to provider-administered sampling methods. Barriers to self-sampling included confidence in the ability to perform the test and perceived cost, and facilitators included convenience and privacy being preserved. The results demonstrate that HPV self-sampling may provide a favorable alternative model of care to the traditional provider-administered Pap testing. These findings add important information to the literature related to promoting cancer screening among women who are under or never screened for cervical cancer.

Low-density solvent based ultrasound-assisted emulsification microextraction and on-column derivatization combined with gas chromatography-mass spectrometry for the determination of carbamate pesticides in environmental water samples.

PubMed

Guo, Liang; Lee, Hian Kee

2012-04-27

A fast and efficient method for the determination of trace level of carbamate pesticides using a lower-density-than-water solvent for ultrasound-assisted emulsification microextraction coupled to on-column derivatization and analysis by GC-MS has been developed and studied. In this approach, a soft plastic Pasteur pipette was employed as a convenient extraction device. Fifty microliters of extraction solvent, of lower density than water, was injected into the sample solution held in the pipette. The latter was immediately immersed in an ultrasound water bath to form an emulsion. After 2 min extraction, the emulsion was fractionated into two layers by centrifugation. The upper layer (organic extract) could be collected conveniently by squeezing the bulb of the pipette, now held upside down, to move it into the narrow stem of the device, facilitating its retrieval for analysis. The extract was then combined with trimethylphenylammonium hydroxide and directly injected into a gas chromatography-mass spectrometry (GC-MS) system for on-column derivatization and analysis. The on-column derivatization provided an added convenience (since a separate step was not necessary). Parameters affecting the derivatization and extraction were investigated. Under the most favorable conditions, the method demonstrated high extraction efficiency with low limits of detection of between 0.01 and 0.1 μg/L, good linearity in the range of 0.05-50 μg/L, to 0.5-100 μg/L, and good repeatability (RSD below 9.2%, n=5). The proposed method was evaluated by determining carbamate pesticides in river water samples. Copyright © 2012 Elsevier B.V. All rights reserved.

Encouragement of Early Academic Skills at Home during Early Childhood Period: Validity and Reliability Study of the EASYC Scale

ERIC Educational Resources Information Center

Kara, H. Gözde Ertürk; Çoksoyluer, Seyda Kiliç

2017-01-01

The current study aims to perform the adaptation of the Encouragement of Academic Skills of Young Children (EASYC) Scale into Turkish. The study group was determined by means of the convenience sampling technique. A total of 124 students aged at 48-84 months were included in the sampling of the study. The data collection tools of the study are the…

Daily sodium and potassium excretion can be estimated by scheduled spot urine collections.

PubMed

Doenyas-Barak, Keren; Beberashvili, Ilia; Bar-Chaim, Adina; Averbukh, Zhan; Vogel, Ofir; Efrati, Shai

2015-01-01

The evaluation of sodium and potassium intake is part of the optimal management of hypertension, metabolic syndrome, renal stones, and other conditions. To date, no convenient method for its evaluation exists, as the gold standard method of 24-hour urine collection is cumbersome and often incorrectly performed, and methods that use spot or shorter collections are not accurate enough to replace the gold standard. The aim of this study was to evaluate the correlation and agreement between a new method that uses multiple-scheduled spot urine collection and the gold standard method of 24-hour urine collection. The urine sodium or potassium to creatinine ratios were determined for four scheduled spot urine samples. The mean ratios of the four spot samples and the ratios of each of the single spot samples were corrected for estimated creatinine excretion and compared to the gold standard. A significant linear correlation was demonstrated between the 24-hour urinary solute excretions and estimated excretion evaluated by any of the scheduled spot urine samples. The correlation of the mean of the four spots was better than for any of the single spots. Bland-Altman plots showed that the differences between these measurements were within the limits of agreement. Four scheduled spot urine samples can be used as a convenient method for estimation of 24-hour sodium or potassium excretion. © 2015 S. Karger AG, Basel.

Seroincidence of non-typhoid Salmonella infections: convenience vs. random community-based sampling.

PubMed

Emborg, H-D; Simonsen, J; Jørgensen, C S; Harritshøj, L H; Krogfelt, K A; Linneberg, A; Mølbak, K

2016-01-01

The incidence of reported infections of non-typhoid Salmonella is affected by biases inherent to passive laboratory surveillance, whereas analysis of blood sera may provide a less biased alternative to estimate the force of Salmonella transmission in humans. We developed a mathematical model that enabled a back-calculation of the annual seroincidence of Salmonella based on measurements of specific antibodies. The aim of the present study was to determine the seroincidence in two convenience samples from 2012 (Danish blood donors, n = 500, and pregnant women, n = 637) and a community-based sample of healthy individuals from 2006 to 2007 (n = 1780). The lowest antibody levels were measured in the samples from the community cohort and the highest in pregnant women. The annual Salmonella seroincidences were 319 infections/1000 pregnant women [90% credibility interval (CrI) 210-441], 182/1000 in blood donors (90% CrI 85-298) and 77/1000 in the community cohort (90% CrI 45-114). Although the differences between study populations decreased when accounting for different age distributions the estimates depend on the study population. It is important to be aware of this issue and define a certain population under surveillance in order to obtain consistent results in an application of serological measures for public health purposes.

Efficacy of low-pressure foam cleaning compared to conventional cleaning methods in the removal of bacteria from surfaces associated with convenience food.

PubMed

Lambrechts, A A; Human, I S; Doughari, J H; Lues, J F R

2014-09-01

Food borne illnesses and food poisoning are cause for concern globally. The diseases are often caused by food contamination with pathogenic bacteria due largely to poor sanitary habits or storage conditions. Prevalence of some bacteria on cleaned and sanitised food contact surfaces from eight convenience food plants in Gauteng (South Africa) was investigated with the view to evaluate the efficacy of the cleaning methods used with such food contact surfaces. The microbial load of eight convenience food manufacturing plants was determined by sampling stainless steel food contact surfaces after they had been cleaned and sanitised at the end of a day's shift. Samples were analysed for Total Plate Count (TPC), Escherichia coli, Salmonella species, Staphylococcus aureus and Listeria species. Results showed that 59 % of the total areas sampled for TPC failed to comply with the legal requirements for surfaces, according to the Foodstuffs, Cosmetics and Disinfectants Act (< 100 cfu.cm(-2)). S. aureus and Salmonella were not detected, but Listeria was detected in 23 % and E. coli in 1.3 % of the samples. Fifty percent (50 %) of the plants applied conventional cleaning methods for cleaning and sanitation and 50 % used the low-pressure foam (LPF) method. There was significant difference (P ≤ 0.05) between the mean TPC values of the conventional cleaning method (14 358.82) compared to that of LPF method (2 386.51) but no significant difference (P > 0.05) in terms of Listeria species isolates obtained from both cleaning methods. The LPF method proved to be the superior cleaning option for lowering TPC counts. Regardless of cleaning method used, pathogens continued to flourish on various surfaces, including dry stainless steel, posing a contamination hazard for a considerable period depending on the contamination level and type of pathogen. Intensive training for proper chemical usage and strict procedural compliance among workers for efficient cleaning procedures is recommended.

Effects of Disasters on Smoking and Relapse: An Exploratory Study of Hurricane Katrina Victims

PubMed Central

Lanctot, Jennifer Q.; Stockton, Michelle B.; Mzayek, Fawaz; Read, Mary; McDevitt-Murphy, Meghan; Ward, Kenneth

2016-01-01

Background Psychosocial stress maintains cigarette use and precipitates relapse, but little is known about how natural disasters in particular affect smoking. Purpose To determine the feasibility of recruiting victims soon after a natural disaster for a survey study, and to assess the types and determinants of changes in smoking behavior resulting from exposure to the disaster. Methods A convenience sample of 35 Hurricane Katrina refugees who had smoked more than 100 cigarettes in their lifetime were surveyed one month after the storm to evaluate changes in smoking behavior. Results Among a small sample of former smokers, more than half relapsed after Katrina, citing stress, urge, and sadness. Among current smokers, 52% increased their smoking after Katrina by more than half a pack per day on average. Most individuals who increased their smoking or relapsed expressed interest in receiving cessation assistance within the next month. Discussion Stress-related increases in smoking and relapse may be common after a natural disaster. Translation to Health Education Practice Health education professionals have an important role to play in responding to changes in tobacco use in the aftermath of disasters. Educational interventions to discourage tobacco use as a coping strategy may be especially warranted given the high level of interest expressed in smoking cessation. PMID:28496561

Impact of hospital atmosphere on perceived health care outcome.

PubMed

Narang, Ritu; Polsa, Pia; Soneye, Alabi; Fuxiang, Wei

2015-01-01

Healthcare service quality studies primarily examine the relationships between patients' perceived quality and satisfaction with healthcare services, clinical effectiveness, service use, recommendations and value for money. These studies suggest that patient-independent quality dimensions (structure, process and outcome) are antecedents to quality. The purpose of this paper is to propose an alternative by looking at the relationship between hospital atmosphere and healthcare quality with perceived outcome. Data were collected from Finland, India, Nigeria and the People's Republic of China. Regression analysis used perceived outcome as the dependent variable and atmosphere and healthcare service quality as independent variables. Findings - Results showed that atmosphere and healthcare service quality have a statistically significant relationship with patient perceived outcomes. The sample size was small and the sampling units were selected on convenience; thus, caution must be exercised in generalizing the findings. The study determined that service quality and atmosphere are considered significant for developing and developed nations. This result could have significant implications for policy makers and service providers developing healthcare quality and hospital atmosphere. Studies concentrate on healthcare outcome primarily regarding population health status, mortality, morbidity, customer satisfaction, loyalty, quality of life, customer behavior and consumption. However, the study exposes how patients perceive their health after treatment. Furthermore, the authors develop the healthcare service literature by considering atmosphere and perceived outcome.

The prevalence of self-reported chronic conditions among Arab, Chaldean, and African Americans in southeast Michigan.

PubMed

Jamil, Hikmet; Dallo, Florence; Fakhouri, Monty; Templin, Thomas; Khoury, Radwan; Fakhouri, Haifa

2009-01-01

While there is a plethora of research on the prevalence of individual chronic conditions, studies that examine the clustering of these conditions are lacking, especially among immigrant, minority groups. Cross-sectional, convenience sample. A self-administered survey was distributed at churches, mosques, and small businesses. Arabs (n = 1383), Chaldeans (n = 868), Blacks (n = 809) and Whites (n = 220) in southeast Michigan. We estimated the prevalence of hypertension, high cholesterol, heart disease, diabetes, asthma, and depression. Using a logistic regression model, we estimated odds ratios and 95% confidence intervals for the association between ethnicity and reporting one or more chronic conditions before and after adjusting for demographic, socioeconomic status, health care, chronic conditions, and health behavior variables. The overall age and sex-adjusted prevalence of having one or more chronic conditions was 44%. Estimates were lower for Chaldeans (32%) compared to Arabs (44%), Whites and Blacks (50% for each group). In the fully adjusted model, Chaldeans were less likely (OR = 0.62; 95% CI = 0.43-0.89) to report having one more chronic conditions compared to Whites. Future studies should employ probability samples, and should collect more detailed sociodemographic and acculturation data, which influence the relationship between race/ethnicity and the prevalence of chronic conditions.

Florbetapir-PET β-amyloid imaging and associated neuropsychological trajectories in survivors of critical illness: A case series.

PubMed

Jackson, James C; Warrington, Hillary J; Kessler, Robert; Kiehl, Amy L; Wesley Ely, E

2018-04-01

Cognitive impairment resembling Alzheimer's disease is common in survivors of critical illness. We hypothesized that Intensive Care Unit (ICU) survivors with cognitive impairment would have significant amyloid and designed a pilot study to explore this relationship. A pilot, case series of a convenience sample of 14 adult medical and surgical ICU survivors, in a clinical neuroradiology clinic. Patients underwent cognitive testing at 3months, 1year, 4years, and 6years after hospital discharge with the Repeatable Battery for the Assessment of Neuropsychological Status. They received a single PET scan using amyloid PET imaging (florbetapir F18) 2 to 4years after their ICU stay. Amyloid (defined as a Standard Uptake Value ratio or SUVr >1.10) was present in 2 of 14 (14%) individuals, both of whom demonstrated significant cognitive impairment yet no consistent decline over time. Of the 6 impaired patients (RBANS<78), 4 (66.7%) were amyloid negative. It is feasible to assess ICU survivors with amyloid imaging. In this small sample, most patients with cognitive impairment were negative on amyloid PET imaging, which raises the possibility that ICU survivors may experience a unique form of dementia not driven by an amyloid related mechanism. Copyright © 2017. Published by Elsevier Inc.

A cross sectional observational study to estimate herd level risk factors for Leptospira spp. serovars in small holder dairy cattle farms in southern Chile.

PubMed

Salgado, Miguel; Otto, Barbara; Sandoval, Errol; Reinhardt, German; Boqvist, Sofia

2014-06-06

The south of Chile constitutes the main cattle milk producing area of the country. Regarding leptospirosis control in Chile, there is neither an official program nor an epidemiological characterization of smallholder dairy farms. This study was carried out to determine Leptospira seroprevalence and to evaluate risk factors associated with seropositivity at herd level in smallholder bovine dairy herds in southern Chile.A cross-sectional study was conducted, and a convenient sample of 1,537 apparently healthy dairy cows was included in the study. Individual blood samples were taken and examined for six selected reference Leptospira serovars by the Microscopic Agglutination Test (MAT). Of the included herds 75% (52/69) showed serological titers against one or more Leptospira serovar. Leptospira borgpetersenii serovar Hardjo was the serovar most frequently (81%) reported from animals with positive results. The variables considered risk factors for Leptospira seropositivity were calve natural breeding system, using a specific calving area and vaccination against Leptospira. Adult cows in contact with calves weaned, proved to be a protective factor against infection. Herds neglecting the management practices mentioned in this study could represent an important source of Leptospira infection for other herds in the same geographic area, as well as for other animal species.

An exploratory study of parent-child communication about sex and the sexual attitudes of early, middle, and late adolescents.

PubMed

Fisher, T D

1986-12-01

In an attempt to examine the relationship between parent-child communication about sex and parent-adolescent attitudes about sex, 12- to 20-year-olds (N = 141) and their parents completed sexual communication and attitude questionnaires. The correlation between parents' and children's attitudes were high for all the early adolescents and low for all the middle adolescents. Only among the late adolescents was there a significant difference in the correlations between the sexual attitudes of parents and their children as a function of family communication level, with the attitudes of adolescents and parents in the high communication group being highly correlated and the attitudes of adolescents and parents in the low communication group not being significantly correlated. Middle adolescents had significantly more permissive sexual attitudes than early and late adolescents. Gender variables were also studied, but conclusions were limited due to the small number of participating fathers. All findings must be tempered with the recognition of the possible sampling bias introduced by the use of a convenience sample. It is suggested that the more responsible sexuality seen in adolescents who can talk to their parents about sex may be a function of the similarity in sexual attitudes between these late adolescents and their parents.

Microchip Module for Blood Sample Preparation and Nucleic Acid Amplification Reactions

PubMed Central

Yuen, Po Ki; Kricka, Larry J.; Fortina, Paolo; Panaro, Nicholas J.; Sakazume, Taku; Wilding, Peter

2001-01-01

A computer numerical control-machined plexiglas-based microchip module was designed and constructed for the integration of blood sample preparation and nucleic acid amplification reactions. The microchip module is comprised of a custom-made heater-cooler for thermal cycling, a series of 254 μm × 254 μm microchannels for transporting human whole blood and reagents in and out of an 8–9 μL dual-purpose (cell isolation and PCR) glass-silicon microchip. White blood cells were first isolated from a small volume of human whole blood (<3 μL) in an integrated cell isolation–PCR microchip containing a series of 3.5-μm feature-sized “weir-type” filters, formed by an etched silicon dam spanning the flow chamber. A genomic target, a region in the human coagulation Factor V gene (226-bp), was subsequently directly amplified by microchip-based PCR on DNA released from white blood cells isolated on the filter section of the microchip mounted onto the microchip module. The microchip module provides a convenient means to simplify nucleic acid analyses by integrating two key steps in genetic testing procedures, cell isolation and PCR and promises to be adaptable for additional types of integrated assays. PMID:11230164

Detailed assessment of the ear in Cornelia de Lange syndrome: comparison with a control sample using the new dysmorphology guidelines.

PubMed

Hunter, Alasdair G W; Collins, Julianne S; Deardorff, Matthew A; Krantz, Ian D

2009-10-01

The literature abounds with reports of malformation syndromes in which human external ears are variously described as dysplastic, abnormal, large/small, low set, typical, or in some way unusual. Rarely is the ear well illustrated or described in meaningful detail. With few exceptions, such as Down syndrome, there is no real understanding of the degree to which ear morphology is affected in a specific syndrome. This paper describes a retrospective attempt to apply the recently published Morphological Definitions of the ear to compare a control sample of convenience with a group of patients with Cornelia de Lange syndrome (CdLS) (all six papers in this issue are available online, open access at http://www3.interscience.wiley.com/journal/121641055/issue). Although this study has a number of limitations, it demonstrates that the method can be successfully applied and is capable of producing data that can be subjected to statistical analysis. The ears of the patients with CdLS were significantly different from the controls over a number of descriptors, the most significant of which included more frequent apparent posterior rotation, a shorter more serpiginous antihelical stem and sharper antihelical to inferior crus angle, a shorter crus helix, a more V-shaped incisura, and a smaller lobe.

Corrosion Testing of 304L SS 3013 Inner Container and Teardrop Samples

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

Tokash, Justin Charles; Hill, Mary Ann; Lillard, Scott

The Department of Energy (DOE) 3013 Standard specifies a minimum of two containers to be used for the storage of plutonium-bearing materials containing at least 30 wt.% plutonium and uranium. Three nested containers are typically used, the outer, inner, and convenience containers, shown in Figure 1. Both the outer and inner containers are sealed with a weld while the innermost convenience container must not be sealed. Lifetime of the containers is expected to be fifty years. The containers are fabricated of austenitic stainless steels (SS) due to their high corrosion resistance. Potential failure mechanisms of the storage containers have beenmore » examined by Kolman and Lillard et al.« less

Assessing Cultural Competence in Graduating Students

ERIC Educational Resources Information Center

Kohli, Hermeet K.; Kohli, Amarpreet S.; Huber, Ruth; Faul, Anna C.

2010-01-01

Twofold purpose of this study was to develop a framework to understand cultural competence in graduating social work students, and test that framework for appropriateness and predictability using multivariate statistics. Scale and predictor variables were collected using an online instrument from a nationwide convenience sample of graduating…

78 FR 73839 - 1,1,1,2 Tetrafluoroethane From the People's Republic of China: Initiation of Countervailing Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-09

... using a statistically valid sampling method to poll the industry. Section 771(4)(A) of the Act defines... subheading 2903.39.2020. Although the HTSUS subheading and CAS registry number are provided for convenience...

Everyday Health Communication Experiences of College Students

ERIC Educational Resources Information Center

Baxter, Leslie; Egbert, Nichole; Ho, Evelyn

2008-01-01

Objective: The authors examined college students' day-to-day health communication experiences. Participants: A convenience sample of 109 midwestern university students participated in the study. Methods: The participants completed health communication diaries for 2 weeks, generating 2,185 records. Frequent health topics included nutrition and…

Eating disorder symptoms and weight and shape concerns in a large web-based convenience sample of women ages 50 and above: results of the Gender and Body Image (GABI) study.

PubMed

Gagne, Danielle A; Von Holle, Ann; Brownley, Kimberly A; Runfola, Cristin D; Hofmeier, Sara; Branch, Kateland E; Bulik, Cynthia M

2012-11-01

Limited research exists on eating disorder symptoms and attitudes and weight and shape concerns in women in midlife to older adulthood. We conducted an online survey to characterize these behaviors and concerns in women ages 50 and above. Participants (n = 1,849) were recruited via the Internet and convenience sampling. Eating disorder symptoms, dieting and body checking behaviors, and weight and shape concerns were widely endorsed. Younger age and higher body mass index (BMI) were associated with greater endorsement of eating disorder symptoms, behaviors, and concerns. Weight and shape concerns and disordered eating behaviors occur in women over 50 and vary by age and BMI. Focused research on disordered eating patterns in this age group is necessary to develop age-appropriate interventions and to meet the developmental needs of an important, growing, and underserved population. Copyright © 2012 Wiley Periodicals, Inc.

ZIF-67 supported on marcoscale resin as an efficient and convenient heterogeneous catalyst for Oxone activation.

PubMed

Wu, Chang-Hsun; Yun, Wan-Chu; Wi-Afedzi, Thomas; Lin, Kun-Yi Andrew

2018-03-15

While metal organic frameworks (MOFs) are promising catalysts for aqueous chemical oxidation, MOFs are typically prepared to be nanoscale and thus less practical for solution-based reactions. Although a few attempts have developed substrate-supported MOFs, many of them are still small and none of them are developed for sulfate-radical based chemical oxidation. However, there is still an urgent demand for developing substrate-supported MOFs which are catalytically effective, conveniently prepared, and simply recyclable. In this study, a macrosphere-supported MOF is successfully fabricated using ion exchange resins as readily available, stable and functionalized macrospheres. Via equilibrating resins with 2-MIM and cobalt ions sequentially, a cobalt-based MOF, zeolitic imidazolate framework-67 (ZIF-67) nanocrystal, is grown on the resin surface via self-assembly. The resulting composite of ZIF "at" resin (abbreviated as ZIF@R) can preserve porous structures and metal coordination of ZIF-67, and also convenient features of resins, making it an advantageous heterogeneous catalyst for activating Oxone in water. As Rhodamine B (RhB) decolorization is employed as a model test for evaluating Oxone activation, ZIF@R is confirmed not only to activate Oxone for full decolorization of RhB but also to exhibit a much higher catalytic activity than Co 3 O 4 , the most typical catalyst for Oxone. ZIF@R could be also re-used to activate Oxone for RhB decolorization without activity loss. These results indicate that ZIF@R is a conveniently prepared and highly effective and stable macroscale catalyst for aqueous chemical oxidation reactions. Copyright © 2017 Elsevier Inc. All rights reserved.

Application of the optimal homotopy asymptotic method to nonlinear Bingham fluid dampers

NASA Astrophysics Data System (ADS)

Marinca, Vasile; Ene, Remus-Daniel; Bereteu, Liviu

2017-10-01

Dynamic response time is an important feature for determining the performance of magnetorheological (MR) dampers in practical civil engineering applications. The objective of this paper is to show how to use the Optimal Homotopy Asymptotic Method (OHAM) to give approximate analytical solutions of the nonlinear differential equation of a modified Bingham model with non-viscous exponential damping. Our procedure does not depend upon small parameters and provides us with a convenient way to optimally control the convergence of the approximate solutions. OHAM is very efficient in practice for ensuring very rapid convergence of the solution after only one iteration and with a small number of steps.

Design, Development, and Testing of a Compound Wing V/TOL small UAS

NASA Technical Reports Server (NTRS)

Logan, Michael J.; Vranas, Thomas L.

2015-01-01

This paper discusses the development and testing of an innovative small UAS (Unmanned Aircraft System). The design of the vehicle was driven by the need to both have long endurance yet still have the convenience of V/TOL (Vertical Take-Off and Landing) operation. The paper discusses some of the design considerations and configurations evaluated in searching for a configuration that met the demanding mission requirements. The paper also discusses some aspects of the compound wing and experimental testing conducted to discern the optimum parameters for the wing's design. The paper discusses the results of the preliminary flight testing and outlines further research to be conducted.

Video-Based Grocery Shopping Intervention Effect on Purchasing Behaviors Among Latina Shoppers.

PubMed

Amaro, Hortensia; Cortés, Dharma E; Garcia, Samantha; Duan, Lei; Black, David S

2017-05-01

To compare changes in food-purchasing knowledge, self-efficacy, and behavior after viewing nutrition education videos among Los Angeles, California Latinas responsible for household grocery shopping. From February to May 2015, a convenience sample of 113 Latinas watched 1 video (El Carrito Saludable) featuring MyPlate guidelines applied to grocery shopping (1-video intervention) and another convenience sample of 105 Latinas watched 2 videos (El Carrito Saludable and Ser Consciente), the latter featuring mindfulness to support attention and overcome distractions while grocery shopping (2-video intervention). We administered questionnaires before and after intervention. A preselected sample in each intervention condition (n = 72) completed questionnaires at 2-months after intervention and provided grocery receipts (before and 2-months after intervention). Knowledge improved in both intervention groups (P < .001). The 2-video group improved more in self-efficacy and use of a shopping list (both P < .05) and purchased more healthy foods (d = 0.60; P < .05) at 2 months than did the 1-video group. Culturally tailored videos that model food-purchasing behavior and mindfulness show promise for improving the quality of foods that Latinas bring into the home.

Video-Based Grocery Shopping Intervention Effect on Purchasing Behaviors Among Latina Shoppers

PubMed Central

Cortés, Dharma E.; Garcia, Samantha; Duan, Lei; Black, David S.

2017-01-01

Objectives. To compare changes in food-purchasing knowledge, self-efficacy, and behavior after viewing nutrition education videos among Los Angeles, California Latinas responsible for household grocery shopping. Methods. From February to May 2015, a convenience sample of 113 Latinas watched 1 video (El Carrito Saludable) featuring MyPlate guidelines applied to grocery shopping (1-video intervention) and another convenience sample of 105 Latinas watched 2 videos (El Carrito Saludable and Ser Consciente), the latter featuring mindfulness to support attention and overcome distractions while grocery shopping (2-video intervention). We administered questionnaires before and after intervention. A preselected sample in each intervention condition (n = 72) completed questionnaires at 2-months after intervention and provided grocery receipts (before and 2-months after intervention). Results. Knowledge improved in both intervention groups (P < .001). The 2-video group improved more in self-efficacy and use of a shopping list (both P < .05) and purchased more healthy foods (d = 0.60; P < .05) at 2 months than did the 1-video group. Conclusions. Culturally tailored videos that model food-purchasing behavior and mindfulness show promise for improving the quality of foods that Latinas bring into the home. PMID:28323473

What is a representative brain? Neuroscience meets population science.

PubMed

Falk, Emily B; Hyde, Luke W; Mitchell, Colter; Faul, Jessica; Gonzalez, Richard; Heitzeg, Mary M; Keating, Daniel P; Langa, Kenneth M; Martz, Meghan E; Maslowsky, Julie; Morrison, Frederick J; Noll, Douglas C; Patrick, Megan E; Pfeffer, Fabian T; Reuter-Lorenz, Patricia A; Thomason, Moriah E; Davis-Kean, Pamela; Monk, Christopher S; Schulenberg, John

2013-10-29

The last decades of neuroscience research have produced immense progress in the methods available to understand brain structure and function. Social, cognitive, clinical, affective, economic, communication, and developmental neurosciences have begun to map the relationships between neuro-psychological processes and behavioral outcomes, yielding a new understanding of human behavior and promising interventions. However, a limitation of this fast moving research is that most findings are based on small samples of convenience. Furthermore, our understanding of individual differences may be distorted by unrepresentative samples, undermining findings regarding brain-behavior mechanisms. These limitations are issues that social demographers, epidemiologists, and other population scientists have tackled, with solutions that can be applied to neuroscience. By contrast, nearly all social science disciplines, including social demography, sociology, political science, economics, communication science, and psychology, make assumptions about processes that involve the brain, but have incorporated neural measures to differing, and often limited, degrees; many still treat the brain as a black box. In this article, we describe and promote a perspective--population neuroscience--that leverages interdisciplinary expertise to (i) emphasize the importance of sampling to more clearly define the relevant populations and sampling strategies needed when using neuroscience methods to address such questions; and (ii) deepen understanding of mechanisms within population science by providing insight regarding underlying neural mechanisms. Doing so will increase our confidence in the generalizability of the findings. We provide examples to illustrate the population neuroscience approach for specific types of research questions and discuss the potential for theoretical and applied advances from this approach across areas.

What is a representative brain? Neuroscience meets population science

PubMed Central

Falk, Emily B.; Hyde, Luke W.; Mitchell, Colter; Faul, Jessica; Gonzalez, Richard; Heitzeg, Mary M.; Keating, Daniel P.; Langa, Kenneth M.; Martz, Meghan E.; Maslowsky, Julie; Morrison, Frederick J.; Noll, Douglas C.; Patrick, Megan E.; Pfeffer, Fabian T.; Reuter-Lorenz, Patricia A.; Thomason, Moriah E.; Davis-Kean, Pamela; Monk, Christopher S.; Schulenberg, John

2013-01-01

The last decades of neuroscience research have produced immense progress in the methods available to understand brain structure and function. Social, cognitive, clinical, affective, economic, communication, and developmental neurosciences have begun to map the relationships between neuro-psychological processes and behavioral outcomes, yielding a new understanding of human behavior and promising interventions. However, a limitation of this fast moving research is that most findings are based on small samples of convenience. Furthermore, our understanding of individual differences may be distorted by unrepresentative samples, undermining findings regarding brain–behavior mechanisms. These limitations are issues that social demographers, epidemiologists, and other population scientists have tackled, with solutions that can be applied to neuroscience. By contrast, nearly all social science disciplines, including social demography, sociology, political science, economics, communication science, and psychology, make assumptions about processes that involve the brain, but have incorporated neural measures to differing, and often limited, degrees; many still treat the brain as a black box. In this article, we describe and promote a perspective—population neuroscience—that leverages interdisciplinary expertise to (i) emphasize the importance of sampling to more clearly define the relevant populations and sampling strategies needed when using neuroscience methods to address such questions; and (ii) deepen understanding of mechanisms within population science by providing insight regarding underlying neural mechanisms. Doing so will increase our confidence in the generalizability of the findings. We provide examples to illustrate the population neuroscience approach for specific types of research questions and discuss the potential for theoretical and applied advances from this approach across areas. PMID:24151336

Automated on-line column-switching high performance liquid chromatography isotope dilution tandem mass spectrometry method for the quantification of bisphenol A, bisphenol F, bisphenol S, and 11 other phenols in urine.

PubMed

Zhou, Xiaoliu; Kramer, Joshua P; Calafat, Antonia M; Ye, Xiaoyun

2014-01-01

Human exposure to bisphenol A (BPA) is widespread. However, in recent years, bisphenol analogs such as bisphenol S (BPS) and bisphenol F (BPF) are replacing BPA in the production of some consumer products. Because human exposure to these alternative bisphenols may occur, biomonitoring of these bisphenol analogs is warranted. In the present study, we developed and validated a sensitive and selective method that uses on-line solid phase extraction coupled to high performance liquid chromatography-isotope dilution tandem mass spectrometry with peak focusing to measure BPA, BPF, BPS, and 11 other environmental phenols in urine. The method required a small amount of sample (100μL) and minimal sample pretreatment. The limits of detection were 0.03ng/mL (BPS), 0.06ng/mL (BPF), 0.10ng/mL (BPA), and ranged from 0.1ng/mL to 1.0ng/mL for the other 11 phenols. In 100 urine samples collected in 2009-2012 from a convenience group of anonymous adults in the United States, of the three bisphenols, we detected BPA at the highest frequency and median concentrations (95%, 0.72ng/mL), followed by BPS (78%, 0.13ng/mL) and BPF (55%, 0.08ng/mL). This sensitive, rugged, and labor and cost-effective method could be used for the analysis of large number of samples for epidemiologic studies. Published by Elsevier B.V.

The mechanical properties of stored red blood cells measured by a convenient microfluidic approach combining with mathematic model.

PubMed

Wang, Ying; You, Guoxing; Chen, Peipei; Li, Jianjun; Chen, Gan; Wang, Bo; Li, Penglong; Han, Dong; Zhou, Hong; Zhao, Lian

2016-03-01

The mechanical properties of red blood cells (RBCs) are critical to the rheological and hemodynamic behavior of blood. Although measurements of the mechanical properties of RBCs have been studied for many years, the existing methods, such as ektacytometry, micropipette aspiration, and microfluidic approaches, still have limitations. Mechanical changes to RBCs during storage play an important role in transfusions, and so need to be evaluated pre-transfusion, which demands a convenient and rapid detection method. We present a microfluidic approach that focuses on the mechanical properties of single cell under physiological shear flow and does not require any high-end equipment, like a high-speed camera. Using this method, the images of stretched RBCs under physical shear can be obtained. The subsequent analysis, combined with mathematic models, gives the deformability distribution, the morphology distribution, the normalized curvature, and the Young's modulus (E) of the stored RBCs. The deformability index and the morphology distribution show that the deformability of RBCs decreases significantly with storage time. The normalized curvature, which is defined as the curvature of the cell tail during stretching in flow, suggests that the surface charge of the stored RBCs decreases significantly. According to the mathematic model, which derives from the relation between shear stress and the adherent cells' extension ratio, the Young's moduli of the stored RBCs are also calculated and show significant increase with storage. Therefore, the present method is capable of representing the mechanical properties and can distinguish the mechanical changes of the RBCs during storage. The advantages of this method are the small sample needed, high-throughput, and easy-use, which make it promising for the quality monitoring of RBCs.

Convenience foods in children's diet and association with dietary quality and body weight status.

PubMed

Alexy, U; Libuda, L; Mersmann, S; Kersting, M

2011-02-01

Pre-prepared commercial foods (convenience foods, CFs) are one aspect of modern dietary habits. The present paper examines the association between CF consumption and dietary quality or body weight status in a sample of German children and adolescents. Linear mixed-effect regression analyses using data from 586 participants (296 boys, 3-18 years) in the Dortmund Nutritional Anthropometric Longitudinally Designed Study, who yearly completed 1890 3-day dietary records and anthropometric measurements in 2004-2008, was used. CF intake (percent total food intake) showed no significant association with macronutrient intakes (%E), with exception of a significant positive association with polyunsaturated fatty acid (PUFA) intake (P<0.0001). Considering only high-energy-dense (ED)-CF (40% of the CF intake), there was a significant negative association with total protein, carbohydrate and saturated fatty acid intake (%E) (P<0.05), and a positive with total fat and PUFA (P<0.01). The nutrient quality index (harmonic mean of 10 vitamins and minerals as the percentage of the reference intakes) showed a significant negative trend with increased consumption of CF (P=0.0013). No significant association between baseline or change in consumption of CF and baseline or change in parameters of body weight (standard deviation score of body mass index (weight/height(2)) or percentage body fat (%BF) estimated from skinfolds) was found. Among boys, baseline consumption of high-ED-CF significantly predicted change in %BF during the study period (β 0.104, P=0.0098). Our results point to an impairment of dietary quality with high consumption of CF and to a small but positive association between consumption of high-ED-CF in boys and weight.

Some Implications of Farm Practice Diffusion--Adoption Research for Extension Program Development. A Research Summary of a Graduate Study.

ERIC Educational Resources Information Center

Jalihal, Krishna A.; Dotson, Robert S.

The study was made to consider cultural factors related to the acceptance or nonacceptance of farm practices. Some major conclusions were: (1) demonstrators should be in the age group 30-45, (2) reading material should be at the seventh or eighth grade level, (3) meetings should be convenient for small or disadvantaged farmers to attend, (4)…

Comprehensive and Critical Literature Review on Insitu Micro-Sensors for Application in Tribology

DTIC Science & Technology

1994-04-01

Electroosmotic flow provides a pumping method that is convenient for small capillaries. Electrophoretic separation is shown to be useful. On the left hand...analysis systems on glass chips (1 centimeter by 2 centimeters or larger) that utilize electroosmotic pumping to drive fluid flow and electrophoretic...elucidate the interaction mechanism. Additionally, using two types of sensors in a mixed array increases selectivity by providing different information

Lego Bricks and the Octet Rule: Molecular Models for Biochemical Pathways with Plastic, Interlocking Toy Bricks

ERIC Educational Resources Information Center

Lin, Henry J.; Lehoang, Jennifer; Kwan, Isabel; Baghaee, Anita; Prasad, Priya; Ha-Chen, Stephanie J.; Moss, Tanesha; Woods, Jeremy D.

2018-01-01

The 8 studs on a 2 × 4 Lego brick conveniently represent the outer shell of electrons for carbon, nitrogen, and oxygen atoms. We used Lego bricks to model these atoms, which are then joined together to form molecules by following the Lewis octet rule. A variety of small biological molecules can be modeled in this way, such as most amino acids,…

Food shopping perceptions, behaviors, and ability to purchase healthful food items in the lower Mississippi delta.

PubMed

McGee, Bernestine B; Johnson, Glenda S; Yadrick, M Kathleen; Richardson, Valerie; Simpson, Pippa M; Gossett, Jeffrey M; Thornton, Alma; Johnson, Crystal; Bogle, Margaret L

2011-01-01

To examine the agreement between perceptions, behaviors, and ability to purchase healthful food in the Lower Mississippi Delta (LMD). A regional food store survey of healthful food options in supermarkets, small/medium stores, and convenience stores. Focus group discussions were conducted on shopping perceptions and behaviors. Counties in Arkansas, Louisiana, and Mississippi. Eighty-one LMD residents, 18-60+ years of age. Perceptions of healthful food and ability to acquire these food items across store types. Focus group data were analyzed using thematic coding. Summary food store statistics were weighted, and estimates were constructed using SUDAAN 9. Data triangulation was achieved by comparing focus group findings with food availability data. A majority (> 85%) of supermarkets had selected vegetables, breads, and cereals perceived as healthful, whereas availability was limited in small to medium grocery stores and convenience stores. Skim milk, perceived as healthful, was limited in all store types. Limited availability and perceived costs of healthful food in the LMD influenced purchasing behaviors. Attitudes and perceptions should be incorporated into intervention development to improve food choices in conjunction with increasing the availability of healthful food in the LMD. Copyright © 2011 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.

Energy dependence measurement of small-type optically stimulated luminescence (OSL) dosimeter by means of characteristic X-rays induced with general diagnostic X-ray equipment.

PubMed

Takegami, Kazuki; Hayashi, Hiroaki; Okino, Hiroki; Kimoto, Natsumi; Maehata, Itsumi; Kanazawa, Yuki; Okazaki, Tohru; Hashizume, Takuya; Kobayashi, Ikuo

2016-01-01

For X-ray inspections by way of general X-ray equipment, it is important to measure an entrance-skin dose. Recently, a small optically stimulated luminescence (OSL) dosimeter was made commercially available by Landauer, Inc. The dosimeter does not interfere with the medical images; therefore, it is expected to be a convenient detector for measuring personal exposure doses. In an actual clinical situation, it is assumed that X-rays of different energies will be detected by a dosimeter. For evaluation of the exposure dose measured by a dosimeter, it is necessary to know the energy dependence of the dosimeter. Our aim in this study was to measure the energy dependence of the OSL dosimeter experimentally in the diagnostic X-ray region. Metal samples weighing several grams were irradiated and, in this way, characteristic X-rays having energies ranging from 8 to 85 keV were generated. Using these mono-energetic X-rays, the dosimeter was irradiated. Simultaneously, the fluence of the X-rays was determined with a CdTe detector. The energy-dependent efficiency of the dosimeter was derived from the measured value of the dosimeter and the fluence. Moreover, the energy-dependent efficiency was calculated by Monte-Carlo simulation. The efficiency obtained in the experiment was in good agreement with that of the simulation. In conclusion, our proposed method, in which characteristic X-rays are used, is valuable for measurement of the energy dependence of a small OSL dosimeter in the diagnostic X-ray region.

Lightweight Integrated Solar Array (LISA): Providing Higher Power to Small Spacecraft

NASA Technical Reports Server (NTRS)

Johnson, Les; Carr, John; Fabisinski, Leo; Lockett, Tiffany Russell

2015-01-01

Affordable and convenient access to electrical power is essential for all spacecraft and is a critical design driver for the next generation of smallsats, including CubeSats, which are currently extremely power limited. The Lightweight Integrated Solar Array (LISA), a concept designed, prototyped, and tested at the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama provides an affordable, lightweight, scalable, and easily manufactured approach for power generation in space. This flexible technology has many wide-ranging applications from serving small satellites to providing abundant power to large spacecraft in GEO and beyond. By using very thin, ultraflexible solar arrays adhered to an inflatable or deployable structure, a large area (and thus large amount of power) can be folded and packaged into a relatively small volume.

Preservice Teachers' Preferences about Instructor Gender

ERIC Educational Resources Information Center

Yapici, Senay

2014-01-01

This is a qualitative research. Interview technique was used to collect data and the data were analyzed using quantifying the qualitative data. The participants were selected using convenience sampling method. They comprised 99 (51 female, 48 male) preservice teachers studying at eleven education faculties around Turkey. The consistency percentage…

Implications for Sexual Assault Prevention: College Students as Prosocial Bystanders

ERIC Educational Resources Information Center

Exner, Deinera; Cummings, Nina

2011-01-01

Prosocial bystander interventions are promising approaches to sexual assault prevention on college campuses. Objective: To assess bystander attitudes among undergraduate students at a northeastern university. Participants: A convenience sample of 188 students from 4 undergraduate classes was surveyed during regularly scheduled class sessions.…

Who Recommends Long-Term Care Matters

ERIC Educational Resources Information Center

Kane, Robert L.; Bershadsky, Boris; Bershadsky, Julie

2006-01-01

Purpose: Making good consumer decisions requires having good information. This study compared long-term-care recommendations among various types of health professionals. Design and Methods: We gave randomly varied scenarios to a convenience national sample of 211 professionals from varying disciplines and work locations. For each scenario, we…

Public Opinion and the NCAA Proposal 42.

ERIC Educational Resources Information Center

Cross, Lawrence H.; Koball, Elizabeth G.

1991-01-01

Surveyed opinions on the National Collegiate Athletic Association's Proposal 42 using a convenience sample of 872 persons. Most respondents felt that college admission tests are biased. Concludes that the controversy will be resolved when American society comes to grips with inequalities in educational and socioeconomic opportunity. (DM)

Intelligence in Bali--A Case Study on Estimating Mean IQ for a Population Using Various Corrections Based on Theory and Empirical Findings

ERIC Educational Resources Information Center

Rindermann, Heiner; te Nijenhuis, Jan

2012-01-01

A high-quality estimate of the mean IQ of a country requires giving a well-validated test to a nationally representative sample, which usually is not feasible in developing countries. So, we used a convenience sample and four corrections based on theory and empirical findings to arrive at a good-quality estimate of the mean IQ in Bali. Our study…

Dried blood spots for the enzymatic diagnosis of lysosomal storage diseases in dogs and cats.

PubMed

Sewell, Adrian C; Haskins, Mark E; Giger, Urs

2012-12-01

In people, lysosomal storage diseases (LSD) can be diagnosed by assaying enzyme activities in dried blood spots (DBS). The aim of this study was to evaluate the feasibility of using DBS samples from dogs and cats to measure lysosomal enzymatic activities and diagnose LSD. Drops of fresh whole blood collected in EDTA from dogs and cats with known or suspected LSD and from clinically healthy dogs and cats were placed on neonatal screening cards, dried, and mailed to the Metabolic Laboratory, University Children's Hospital, Frankfurt, Germany. Activities of selected lysosomal enzymes were measured using fluorescent substrates in a 2-mm diameter disk (~2.6 μL blood) punched from the DBS. Results were expressed as nmol substrate hydrolyzed per mL of blood per minute or hour. Reference values were established for several lysosomal enzyme activities in DBS from dogs and cats; for most enzymes, activities were higher than those published for human samples. Activities of β-glucuronidase, N-acetylglucosamine-4-sulfatase (arylsulfatase B), α-mannosidase, α-galactosidase, α-fucosidase, and hexosaminidase A were measureable in DBS from healthy cats and dogs; α-iduronidase activity was measureable only in cats. In samples from animals with LSD, markedly reduced activity of a specific enzyme was found. In contrast, in samples from cats affected with mucolipidosis II, activities of lysosomal enzymes were markedly increased. Measurement of lysosomal enzyme activities in DBS provides an inexpensive, simple, and convenient method to screen animals for suspected LSD and requires only a small sample volume. For diseases in which the relevant enzyme activity can be measured in DBS, a specific diagnosis can be made. © 2012 American Society for Veterinary Clinical Pathology.

Is case-based learning an effective teaching strategy to challenge students' alternative conceptions regarding chemical kinetics?

NASA Astrophysics Data System (ADS)

Yalçınkaya, Eylem; Taştan-Kırık, Özgecan; Boz, Yezdan; Yıldıran, Demet

2012-07-01

Background: Case-based learning (CBL) is simply teaching the concept to the students based on the cases. CBL involves a case, which is a scenario based on daily life, and study questions related to the case, which allows students to discuss their ideas. Chemical kinetics is one of the most difficult concepts for students in chemistry. Students have generally low levels of conceptual understanding and many alternative conceptions regarding it. Purpose: This study aimed to explore the effect of CBL on dealing with students' alternative conceptions about chemical kinetics. Sample: The sample consists of 53 high school students from one public high school in Turkey. Design and methods : Nonequivalent pre-test and post-test control group design was used. Reaction Rate Concept Test and semi-structured interviews were used for data collection. Convenience sampling technique was followed. For data analysis, the independent samples t-test and ANOVA was performed. Results : Both concept test and interview results showed that students instructed with cases had better understanding of core concepts of chemical kinetics and had less alternative conceptions related to the subject matter compared to the control group students, despite the fact that it was impossible to challenge all the alternative conceptions in the experimental group. Conclusions: CBL is an effective teaching method for challenging students' alternative conceptions in the context of chemical kinetics. Since using cases in small groups and whole class discussions has been found to be an effective way to cope with the alternative conceptions, it can be applied to other subjects and grade levels in high schools with a higher sample size. Furthermore, the effect of this method on academic achievement, motivation and critical thinking skills are other variables that can be investigated for future studies in the subject area of chemistry.

Can smartphones measure momentary quality of life and participation? A proof of concept using experience sampling surveys with university students.

PubMed

Liddle, Jacki; Wishink, Anna; Springfield, Liz; Gustafsson, Louise; Ireland, David; Silburn, Peter

2017-08-01

Understanding quality of life and participation is a key aspect of occupational therapy research. The use of smartphones to deliver experience-sampling surveys may provide an accessible way to monitor these outcomes. This study used smartphone-based experience sampling methods (ESM) to investigate factors influencing momentary quality of life (mQOL) of university students. A convenience sample of students at an Australian university participated. Using a custom smartphone application, ESM surveys were sent six to eight times, every second day, over a week. Participants indicated their mQOL, occupational participation, occupational enjoyment, social context and location via surveys and provided demographic and health information in a single self-report questionnaire. The relationship between mQOL and variables was analysed at the survey level using logistic regression. Forty students completed 391 surveys. Higher mQOL was significantly related to participation in productive occupations (z = 3.48; P = 0.001), moderate (z = 4.00; P < 0.001) or high occupational enjoyment (z = 7.06; P < 0.001), being with someone (z = 2.15, P = 0.031), being at home (z = 2.49; P = 0.013) and an excellent self-rated health status (z = 2.35; P = 0.019). The magnitude of differences in mQOL was small. This study suggests that mQOL amongst university students relates to personal, environmental and occupational factors. The use of smartphone-based ESM appears to be a practical approach for investigating participation and QOL. Further research utilising a more diverse sample, analysing at the individual level, and using ESM in conjunction with other methodologies is recommended. © 2017 Occupational Therapy Australia.

Quantitative measurement of the chemical composition of geological standards with a miniature laser ablation/ionization mass spectrometer designed for in situ application in space research

NASA Astrophysics Data System (ADS)

Neuland, M. B.; Grimaudo, V.; Mezger, K.; Moreno-García, P.; Riedo, A.; Tulej, M.; Wurz, P.

2016-03-01

A key interest of planetary space missions is the quantitative determination of the chemical composition of the planetary surface material. The chemical composition of surface material (minerals, rocks, soils) yields fundamental information that can be used to answer key scientific questions about the formation and evolution of the planetary body in particular and the Solar System in general. We present a miniature time-of-flight type laser ablation/ionization mass spectrometer (LMS) and demonstrate its capability in measuring the elemental and mineralogical composition of planetary surface samples quantitatively by using a femtosecond laser for ablation/ionization. The small size and weight of the LMS make it a remarkable tool for in situ chemical composition measurements in space research, convenient for operation on a lander or rover exploring a planetary surface. In the laboratory, we measured the chemical composition of four geological standard reference samples USGS AGV-2 Andesite, USGS SCo-l Cody Shale, NIST 97b Flint Clay and USGS QLO-1 Quartz Latite with LMS. These standard samples are used to determine the sensitivity factors of the instrument. One important result is that all sensitivity factors are close to 1. Additionally, it is observed that the sensitivity factor of an element depends on its electron configuration, hence on the electron work function and the elemental group in agreement with existing theory. Furthermore, the conformity of the sensitivity factors is supported by mineralogical analyses of the USGS SCo-l and the NIST 97b samples. With the four different reference samples, the consistency of the calibration factors can be demonstrated, which constitutes the fundamental basis for a standard-less measurement-technique for in situ quantitative chemical composition measurements on planetary surface.

Point of Sale Scanner Data for Rapid Surveillance of the E-cigarette Market.

PubMed

Day, Hannah R; Ambrose, Bridget K; Schroeder, Megan J; Corey, Catherine G

2017-01-01

Describe e-cigarette sales trends and market share from U.S. convenience stores and mass market retailers. We used Nielsen Scantrack to calculate U.S. e-cigarette sales market share from convenience and mass market channels during the 4-week period ending 1/19/13 through the period ending 12/19/15. Internet searches were used to supplement Nielsen product information. From 2013 to 2015, rechargeable e-cigarette brands VUSE and MarkTen experienced the largest growth in Nielsen channels. E-liquid and tank type brands Vapin Plus and Haus experienced growth although their Nielsen market share is small compared to other brands. Sales of brands with high labeled nicotine content (according to packaging or website) increased. Fruit-flavored sales increased rapidly in Nielsen, yet still represent a minority of market share in these channels. Market-leading e-cigarette brands changed substantially in Nielsen channels from 2013 to 2015. Brand leaders in these channels are now owned by tobacco companies. Changes in labelled nicotine content and fruit-flavored products and product types suggest that as e-cigarette use increases, convenience store and mass market channels are offering new products to meet consumer preferences; however, Nielsen channels do not represent the entire e-cigarette marketplace.

Determination of trace metals in drinking water using solid-phase extraction disks and X-ray fluorescence spectrometry.

PubMed

Hou, Xiandeng; Peters, Heather L; Yang, Zheng; Wagner, Karl A; Batchelor, James D; Daniel, Meredith M; Jones, Bradley T

2003-03-01

A convenient method is described for monitoring Cd, Ni, Cu, and Pb at trace levels in drinking water samples. These metals are preconcentrated on a chelating solid-phase extraction disk and then determined by X-ray fluorescence spectrometry. The method tolerates a wide pH range (pH 6-14) and a large amount of alkaline and alkaline earth elements. The preconcentration factor is well over 1600, assuming a 1 L water sample volume. The limits of detection for Cd, Ni, Cu, and Pb are 3.8, 0.6, 0.4, and 0.3 ng/mL, respectively. These are well below the federal maximum contaminant level values, which are 5, 100, 1300, and 15 ng/mL, respectively. The proposed method has many advantages including ease of operation, multielement capability, nondestructiveness, high sensitivity, and relative cost efficiency. The solid-phase extraction step can be conducted in the field and then the disks can be mailed to a laboratory for the analysis, eliminating the cost of transporting large volumes of water samples. Furthermore, the color of the used extraction disk provides an initial estimate of the degree of contamination for some transition metals (for example, Ni and Cu). Thus, the overall cost for analysis of metals in drinking water can be minimized by implementing the method, and small water supply companies with limited budgets will be better able to comply with the Safe Drinking Water Act.

Patterns of NPS Use and Risk Reduction in Slovenia.

PubMed

Sande, Matej; Paš, Mina; Nahtigal, Klara; Šabić, Simona

2018-01-15

The following study presents factors influencing the decision to use/not to use new psychoactive substances (NPS), various patterns of NPS use, the problems experienced by users, and the methods for reducing the risks associated with NPS use. The study seeks to provide an in-depth look into the characteristics of NPS use and support the planning of targeted interventions in the field of NPS. The study involved 19 in-depth interviews carried out with 25 individuals divided into three subsamples in order to gain insight into the various experiences of NPS users. The interviews were conducted in Slovenia between December 2013 and October 2014. The sample was obtained by using the convenience sampling and snowball sampling methods. The main pattern of NPS use determined by the study concerned synthetic cathinones, specifically 3-MMC, with binge use spanning several days being a prominent feature. The main risks involving NPS use were: mixing various drugs, inappropriate dosing, lack of information prior to use, and the use of unknown substances. Several users spoke about effective strategies for reducing risks, such as obtaining information beforehand, using one's own implements and using only small quantities of unknown substances. Conclusions/Importance: The study revealed various factors based on which users decide to use NPS. Furthermore, users reported a number of problems resulting from NPS use, while risk reduction strategies are employed to a much lesser extent. Based on the results obtained, specific intervention efforts concerning NPS use and targeting specific groups of younger users were designed.

Passive Synthetic Aperture Radar Imaging Using Commercial OFDM Communication Networks

DTIC Science & Technology

2012-09-13

baseband sampling is key to ensure proper correlation with a reference signal. The DFT represents the sam- pled spectrum of a periodic discrete sequence...convenient to sample the baseband time domain segments at a rate of Ts/N . In this way, the segments are easily correlated to the elemental form of the...phase history solution of Gp ,l[k ′ n] = Sp,l,n ϕp,l,ndp,l,nN2 , dp,l,n 6= 0. (5.5.13) The segment need not be limited to N samples . For segments of length

The fragmented testis method: development and its advantages of a new quantitative evaluation technique for detection of testis-ova in male fish.

PubMed

Lin, Bin-Le; Hagino, Satoshi; Kagoshima, Michio; Iwamatsu, Takashi

2009-02-01

A new quantitative evaluation technique, termed the fragmented testis method, has been developed for the detection of testis-ova in genotypic male fish using the medaka (Oryzias latipes). The routine traditional histological method for detection of testis-ova in male fish exposed to estrogens or suspected endocrine-disrupting chemicals has several disadvantages, including possible oversight of testis-ova due to limited sampling of selected tissue sections. The method we have developed here allows for the accurate determination of the developmental stages and the number and the size of testis-ova in a whole testis. Each testis was removed from the fish specimen, fixed with 10% buffered formalin solution, and then divided into small fragments on a glass slide with a dissecting needle or scalpel and aciform forceps in glycerin solution containing a small amount of methylene blue or toluidine blue. If present, all developing testis-ova of various sizes in fragmented testicular tissues were clearly stained and were observable under a dissecting microscope. Testis-ova occurred in controls were ascertained, while spermatozoa were also distinguishable using this method. This proved to be a convenient and cost-effective method for quantitatively evaluating testis-ova appearance in fish, and it may help to clarify the mechanism of testis-ova formation and the biological significance of testis-ova in future studies of endocrine disruption.

Mobile and Home-based Vendors’ Contributions to the Retail Food Environment in Rural South Texas Mexican-origin Settlements

PubMed Central

Valdez, Zulema; Dean, Wesley R; Sharkey, Joseph R

2012-01-01

A growing concern with high rates of obesity and overweight among immigrant minority populations in the U.S. has focused attention on the availability and accessibility to healthy foods in such communities. Small-scale vending in rural, impoverished and underserved areas, however, is generally overlooked; yet, this type of informal activity and source for food is particularly important in such environs, or “food desserts,” where traditional forms of work and mainstream food outlets are limited or even absent. This exploratory study investigates two types of small-scale food vending that take place in rural colonias, or Mexican-origin settlements along the South Texas border with Mexico: mobile and home-based. Using a convenience sample of 23 vendors who live and work in Texas colonias, this study identifies the characteristics associated with mobile and home-based food vendors and their businesses and its contributions to the rural food environment. Findings reveal that mobile and home-based vending provides a variety of food and beverage options to colonia residents, and suggests that home-based vendors contribute a greater assortment of food options, including some healthier food items, than mobile food vendors, which offer and sell a limited range of products. Findings may contribute to the development of innovative policy solutions and interventions aimed at increasing healthy food options or reducing health disparities in immigrant communities. PMID:22531289

Two continuous coupled assays for ornithine-δ-aminotransferase.

PubMed

Juncosa, Jose I; Lee, Hyunbeom; Silverman, Richard B

2013-09-15

We have developed two new continuous coupled assays for ornithine-δ-aminotransferase (OAT) that are more sensitive than previous methods, measure activity in real time, and can be carried out in multiwell plates for convenience and high throughput. The first assay is based on the reduction of Δ(1)-pyrroline-5-carboxylate (P5C), generated from ornithine by OAT, using human pyrroline 5-carboxylate reductase 1 (PYCR1), which results in the concomitant oxidation of NADH (nicotinamide adenine dinucleotide, reduced form) to NAD⁺ (nicotinamide adenine dinucleotide, oxidized form). This procedure was found to be three times more sensitive than previous methods and is suitable for the study of small molecules as inhibitors or inactivators of OAT or as a method to determine OAT activity in unknown samples. The second method involves the detection of L-glutamate, produced during the regeneration of the cofactor pyridoxal 5'-phosphate (PLP) of OAT by an unamplified modification of the commercially available Amplex Red L-glutamate detection kit (Life Technologies). This assay is recommended for the determination of the substrate activity of small molecules against OAT; measuring the transformation of L-ornithine at high concentrations by this assay is complicated by the fact that it also acts as a substrate for the L-glutamate oxidase (GluOx) reporter enzyme. Copyright © 2013 Elsevier Inc. All rights reserved.

Sampling in epidemiological research: issues, hazards and pitfalls.

PubMed

Tyrer, Stephen; Heyman, Bob

2016-04-01

Surveys of people's opinions are fraught with difficulties. It is easier to obtain information from those who respond to text messages or to emails than to attempt to obtain a representative sample. Samples of the population that are selected non-randomly in this way are termed convenience samples as they are easy to recruit. This introduces a sampling bias. Such non-probability samples have merit in many situations, but an epidemiological enquiry is of little value unless a random sample is obtained. If a sufficient number of those selected actually complete a survey, the results are likely to be representative of the population. This editorial describes probability and non-probability sampling methods and illustrates the difficulties and suggested solutions in performing accurate epidemiological research.

Sampling in epidemiological research: issues, hazards and pitfalls

PubMed Central

Tyrer, Stephen; Heyman, Bob

2016-01-01

Surveys of people's opinions are fraught with difficulties. It is easier to obtain information from those who respond to text messages or to emails than to attempt to obtain a representative sample. Samples of the population that are selected non-randomly in this way are termed convenience samples as they are easy to recruit. This introduces a sampling bias. Such non-probability samples have merit in many situations, but an epidemiological enquiry is of little value unless a random sample is obtained. If a sufficient number of those selected actually complete a survey, the results are likely to be representative of the population. This editorial describes probability and non-probability sampling methods and illustrates the difficulties and suggested solutions in performing accurate epidemiological research. PMID:27087985

Compliance to two city convenience store ordinance requirements

PubMed Central

Menéndez, Cammie K Chaumont; Amandus, Harlan E; Wu, Nan; Hendricks, Scott A

2015-01-01

Background Robbery-related homicides and assaults are the leading cause of death in retail businesses. Robbery reduction approaches focus on compliance to Crime Prevention Through Environmental Design (CPTED) guidelines. Purpose We evaluated the level of compliance to CPTED guidelines specified by convenience store safety ordinances effective in 2010 in Dallas and Houston, Texas, USA. Methods Convenience stores were defined as businesses less than 10 000 square feet that sell grocery items. Store managers were interviewed for store ordinance requirements from August to November 2011, in a random sample of 594 (289 in Dallas, 305 in Houston) convenience stores that were open before and after the effective dates of their city’s ordinance. Data were collected in 2011 and analysed in 2012–2014. Results Overall, 9% of stores were in full compliance, although 79% reported being registered with the police departments as compliant. Compliance was consistently significantly higher in Dallas than in Houston for many requirements and by store type. Compliance was lower among single owner-operator stores compared with corporate/franchise stores. Compliance to individual requirements was lowest for signage and visibility. Conclusions Full compliance to the required safety measures is consistent with industry ‘best practices’ and evidence-based workplace violence prevention research findings. In Houston and Dallas compliance was higher for some CPTED requirements but not the less costly approaches that are also the more straightforward to adopt. PMID:26337569

The Social Dimension of Distance Learning by Interactive Television: A Qualitative Study

ERIC Educational Resources Information Center

Zhao, Liang

2011-01-01

This qualitative study examined instructors' and students' perceptions of social relationship in distance learning. Interview and observational data were collected and analyzed to generate theories. Convenient sampling was used. Factors influencing a sense of distance were analyzed. Findings revealed greater difficulty establishing a social…

Students' Use of Electronic Support Tools in Mathematics

ERIC Educational Resources Information Center

Crawford, Lindy; Higgins, Kristina N.; Huscroft-D'Angelo, Jacqueline N.; Hall, Lindsay

2016-01-01

This study investigated students' use of electronic support tools within a computer-based mathematics program. Electronic support tools are tools, such as hyperlinks or calculators, available within many computer-based instructional programs. A convenience sample of 73 students in grades 4-6 was selected to participate in the study. Students…

Measuring Successful Aging in Southern Black Older Adults

ERIC Educational Resources Information Center

Troutman, Meredith; Nies, Mary A.; Bentley, Monica

2011-01-01

With the growing size of the population of aging Black individuals, it is important to understand successful aging in this group. This study, therefore, piloted the Successful Aging Inventory (SAI) with a convenience sample of Black older adults. Participants completed a demographic form, the SAI, Purpose in Life Test, Life Satisfaction…

75 FR 20600 - Proposed Data Collections Submitted for Public Comment and Recommendations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-20

... infection. This research is being conducted by three sites to pilot test three unique HIV risk reduction... culturally appropriate interventions for this target population. The intervention evaluations are a pre-post test design (i.e., baseline assessment and 3-month follow-up assessment) with three convenience samples...

Science Teachers in Deaf Education: A National Survey of K-8 Teachers

ERIC Educational Resources Information Center

Shaw, Cynthia

2009-01-01

A survey was conducted with 67 science teachers who taught deaf children at the elementary school level. Teacher background variables, information about teacher preparation and certification, preferred teaching methods, communication methodologies, curriculum, and the use of technology were gathered. A purposeful, convenience sampling technique…

An Exploration of EFL Teachers' Attributions

ERIC Educational Resources Information Center

Ghonsooly, Behzad; Ghanizadeh, Afsaneh; Ghazanfari, Mohammad; Ghabanchi, Zargham

2015-01-01

The present study investigated English as a foreign language (EFL) teachers' attributions of success and failure. It also set out to investigate whether these attributions vary by teachers' age, teaching experience, gender and educational level. To do so, 200 EFL teachers were selected according to convenience sampling among EFL teachers teaching…

Perceived Social Support Mediating the Relationship between Perceived Stress and Job Satisfaction

ERIC Educational Resources Information Center

Sultan, Sarwat; Rashid, Safia

2015-01-01

This research was conducted to examine the mediating effect of perceived social support between perceived stress and job satisfaction among employees. A conveniently selected sample of 280 employees provided the information on Perceived Social Support Scale, Perceived Stress Scale, and Job Satisfaction Survey. Employing Regression analyses,…

Students' Attitudes toward Introductory Physics Course

ERIC Educational Resources Information Center

Demirci, Neset

2004-01-01

The problem examined in this study deals with students' attitude toward physics among the freshmen and sophomore students who were taking first introductory physics course. In the study there were 176 students, and they were chosen sample of convenience from Florida Institute of Technology, Melbourne, Florida. 125 subjects were male students, and…

Iron metabolism in African American women in the second and third trimesters of high-risk pregnancies

USDA-ARS?s Scientific Manuscript database

Objective: To examine iron metabolism during the second and third trimesters in African American women with high-risk pregnancies. Design: Longitudinal pilot study. Setting: Large, university-based, urban Midwestern U.S. medical center. Participants: Convenience sample of 32 African American wome...

Social Experiences in Infancy and Early Childhood Co-Sleeping

ERIC Educational Resources Information Center

Hayes, Marie J.; Fukumizu, Michio; Troese, Marcia; Sallinen, Bethany A.; Gilles, Allyson A.

2007-01-01

Infancy and early childhood sleep-wake behaviours from current and retrospective parental reports were used to explore the relationship between sleeping arrangements and parent-child nighttime interactions at both time points. Children (N = 45) from educated, middle-class families, mostly breastfed in infancy, composed a convenience sample that…

Practicing Professional Values: Factors Influencing Involvement in Social Work Student Organizations

ERIC Educational Resources Information Center

Martindale, Dorothy; Olate, René; Anderson, Keith A.

2017-01-01

One of the most promising avenues for the development of professional values is involvement in professional student organizations. A convenience sample of baccalaureate social work students (n = 482) was drawn from 15 institutions. Regression analyses revealed several predictors of involvement in social work student organizations, including…

Explaining Couple Cohesion in Different Types of Gay Families

ERIC Educational Resources Information Center

van Eeden-Moorefield, Brad; Pasley, Kay; Crosbie-Burnett, Margaret; King, Erin

2012-01-01

This Internet-based study used data from a convenience sample of 176 gay men in current partnerships to examine differences in outness, cohesion, and relationship quality between three types of gay male couples: first cohabiting partnerships, repartnerships, and gay stepfamilies. Also, we tested whether relationship quality mediated the link…

The Surgical Technologist Learning Partnership: A Comparison of Factors in a Preceptor Relationship

ERIC Educational Resources Information Center

Ross, Tracey A.

2008-01-01

This quantitative, descriptive study examined the specific factors that novice surgical technologists (preceptees) and practicing surgical technologists (preceptors) perceived as important to a successful learning partnership. The Learning Partnership Survey was administered to a convenience sample of 66 surgical technologists employed at an acute…

School-Based Sexuality Education in Portugal: Strengths and Weaknesses

ERIC Educational Resources Information Center

Rocha, Ana Cristina; Leal, Cláudia; Duarte, Cidália

2016-01-01

Portugal, like many other countries, faces obstacles regarding school-based sexuality education. This paper explores Portuguese schools' approaches to implementing sexuality education at a local level, and provides a critical analysis of potential strengths and weaknesses. Documents related to sexuality education in a convenience sample of 89…

Can a Library Building's Design Cue New Behaviors? A Case Study

ERIC Educational Resources Information Center

O'Kelly, Mary; Scott-Webber, Lennie; Garrison, Julie; Meyer, Kristin

2017-01-01

This study explores the relationship between architecture and interior space on student engagement at a newly constructed academic library. Using an action, mixed-methods approach with a convenience sample, researchers evaluated 744 photographs, 125 behavioral observations, and six group interviews. Analysis revealed four key attributes of…

Exploring the Influence of Nature Relatedness and Perceived Science Knowledge on Proenvironmental Behavior

ERIC Educational Resources Information Center

Obery, Amanda; Bangert, Arthur

2017-01-01

This study was undertaken to investigate the factors influencing proenvironmental behavior of individuals residing in the Northern Rocky Mountains (N = 267). Measures of relatedness to nature and perceived science knowledge were collected through a convenience sample approach using multiple avenues such as city email lists, organizational…

An Assessment of Perceived Emotional Intelligence and Health Behaviors among College Students

ERIC Educational Resources Information Center

Pettit, Michele L.; Jacobs, Sue C.; Page, Kyle S.; Porras, Claudia V.

2009-01-01

The purpose of this study was to assess the relationship between perceived emotional intelligence (i.e., recognizing, expressing, monitoring, managing, and reflecting on emotions) (Presbury, Echterling, & McKee, 2007) and self-reported health behaviors among college students. A convenience sample of 418 undergraduates completed online surveys…

The Concrete-Representational-Abstract Sequence of Instruction in Mathematics Classrooms

ERIC Educational Resources Information Center

Mudaly, Vimolan; Naidoo, Jayaluxmi

2015-01-01

The purpose of this paper is to explore how master mathematics teachers use the concrete-representational-abstract (CRA) sequence of instruction in mathematics classrooms. Data was collected from a convenience sample of six master teachers by observations, video recordings of their teaching, and semi-structured interviews. Data collection also…

Accuracy of activPAL Self-Attachment Methods

ERIC Educational Resources Information Center

Kringen, Nina L.; Healy, Genevieve N.; Winkler, Elisabeth A. H.; Clark, Bronwyn K.

2016-01-01

This study examined the accuracy of self-attachment of the activPAL activity monitor. A convenience sample of 50 participants self-attached the monitor after being presented with written material only (WMO) and then written and video (WV) instructions; and completed a questionnaire regarding the acceptability of the instructional methods.…

The Value of LIS Schools' Research Topics to Library Authors' Professional Work

ERIC Educational Resources Information Center

Perkins, Gay Helen; Helbig, Tuesdi L.

2008-01-01

Stoan's distinction between library skills and research skills based on different philosophies of information seeking suggests the value of training in research methodology for the librarian. Such training could lead to more effective patron consultations, committee/administrative work, and personal research. Thus, a convenience sample of…

The Impact of Social Support on Institutional Integration among International Students in the Midwest

ERIC Educational Resources Information Center

McSorley, Leah D.

2017-01-01

International students experience unique challenges as they pursue higher education in the United States. This study explored the relationships and traits that impact international students' social and academic integration (together called institutional integration). A purposeful convenience sample of international students enrolled at two small…

Coping Behaviors of Residence Hall Directors

ERIC Educational Resources Information Center

Wilkes, Ben

2017-01-01

This mixed-methods study examined tertiary-level residence-hall directors' reported coping behaviors for three systems of stress: environmental, personal, and work. It surveyed a convenience sample of 128 respondents using the Brief COPE scale (Carver, 1997). Reported length of service, genders, and hall populations were matched with 28 types of…

HPV Knowledge and Vaccine Acceptability among Hispanic Fathers

ERIC Educational Resources Information Center

Kornfeld, Julie; Byrne, Margaret M.; Vanderpool, Robin; Shin, Sarah; Kobetz, Erin

2013-01-01

The purpose of this study was to examine human papillomavirus (HPV) knowledge and vaccine acceptability in a convenience sample of immigrant Hispanic men, many of whom are parents of adolescents. Data on 189 male callers were collected from the National Cancer Institute's Cancer Information Service Spanish-language call center. Most participants…

Conflict Management Styles in an HBCU HSI Community College Setting

ERIC Educational Resources Information Center

Schmittou, Natasha P.

2012-01-01

The purpose of this quantitative study is to investigate the conflict management styles in an HBCU and HSI community college and how gender, power position, age, educational level, and ethnicity influence conflict management. A convenience sample of 80 administrators and 220 subordinates completed an electronic demographic survey and the…

Health Practices of School Nurses

ERIC Educational Resources Information Center

Petch-Levine, Deborah; Cureton, Virginia Young; Canham, Daryl; Murray, Meg

2003-01-01

The health practices of school nurses affect our role as advocates and educators to promote the health of youth. This study describes the health practices of a convenience sample of 388 school nurses who attended the business meeting at an annual school nurse conference. A self-administered, 40-item questionnaire identified health practices of…

Sexual Values of 783 Undergraduates

ERIC Educational Resources Information Center

Richey, Emily; Knox, David; Zusman, Marty

2009-01-01

The sexual values of absolutism (abstinence until marriage), relativism (sexual decisions made in reference to the nature of the relationship), and hedonism ("if it feels good, do it") were assessed in a convenience sample of 783 undergraduate students at a large southeastern university. Results revealed that relativism (62.1%) was the predominate…

Instructional Coach Job Satisfaction: An Exploration of Role Stressors

ERIC Educational Resources Information Center

Debacker, Jeffrey Paul

2013-01-01

This mixed methods dissertation examines the relationships between role conflict and job satisfaction, role ambiguity and job satisfaction, and role conflict and job satisfaction within a convenience sample of American instructional coaches (n = 46). Theoretically, this analysis is formed by Merton's idea of role-sets and how instructional…

Critical Thinking: Comparing Instructional Methodologies in a Senior-Year Learning Community

ERIC Educational Resources Information Center

Zelizer, Deborah A.

2013-01-01

This quasi-experimental, nonequivalent control group study compared the impact of Ennis's (1989) mixed instructional methodology to the immersion methodology on the development of critical thinking in a multicultural, undergraduate senior-year learning community. A convenience sample of students (n =171) were selected from four sections of a…

Perceived School Safety: Visual Narratives from the Middle Grades

ERIC Educational Resources Information Center

Biag, Manuelito

2014-01-01

Using participatory visual research methods, this study examined how certain low-income, urban youth in a high-minority middle school characterized safe and unsafe spaces on campus. Drawing from a convenience sample of identified gifted students in one classroom (N = 20), results suggested how caring support from adults, friendly peer…

The Effects of Extrinsic Rewards on Admissions Counselors' Performance

ERIC Educational Resources Information Center

Gardner-Engel, Miriam

2010-01-01

This study examines the best ways to motivate college admissions counselors. A review of literature revealed multiple perspectives on intrinsic and extrinsic as well as tangible and intangible rewards. Primary research was designed to examine the impact of tangible rewards and verbal reinforcements with a convenience sample of nine college…

Knowledge of Breast Cancer and Screening Practices

ERIC Educational Resources Information Center

Vahabi, Mandana

2005-01-01

Objective: To assess young women's breast health knowledge and explore its relation to the use of screening mammography. Methods: A convenience sample of 180 women aged 25-45 residing in Toronto, Canada, with no history of breast cancer and mammography received an information brochure and four questionnaires which assessed their knowledge of…

Mothers' Perceptions of Female Genital Mutilation

ERIC Educational Resources Information Center

Ahanonu, E. L.; Victor, O.

2014-01-01

The practice of female genital mutilation (FGM) is widespread in Nigeria. This study was conducted to assess the perceptions of FGM among mothers at a primary healthcare centre in Lagos, Nigeria. A convenience sample of 95 mothers completed the pre-tested, semi-structured questionnaires. Data analysis was carried out using descriptive statistics…

Should Reproductive Anatomy Be Taught in University Health Courses?

ERIC Educational Resources Information Center

Powell, Brent; Fletcher, J. Sue

2013-01-01

There has been little research on undergraduate reproductive anatomy education. This pilot study explores knowledge of anatomical reproductive anatomy among university students in a lower division and upper division health course. Using a Qualtrics survey program, a convenience sample of 120 lower division and 157 upper division students for a…

Couples’ Reasons for Cohabitation: Associations with Individual Well-Being and Relationship Quality

PubMed Central

Rhoades, Galena K.; Stanley, Scott M.; Markman, Howard J.

2009-01-01

This study used a new measure to examine how different types of reasons for cohabitation were associated with individual well-being and relationship quality in a sample of 120 cohabiting heterosexual couples (N = 240). Spending more time together and convenience were the most strongly endorsed reasons. The degree to which individuals reported cohabiting to test their relationships was associated with more negative couple communication and more physical aggression as well as lower relationship adjustment, confidence, and dedication. Testing the relationship was also associated with higher levels of attachment insecurity and more symptoms of depression and anxiety. Men were more likely than women to endorse testing their relationships and less likely to endorse convenience as a reason for cohabiting. PMID:19756225

Drug sampling in dermatology.

PubMed

Reid, Erika E; Alikhan, Ali; Brodell, Robert T

2012-01-01

The use of drug samples in a dermatology clinic is controversial. Drug samples are associated with influencing physician prescribing patterns often toward costlier drugs, increasing health care costs, increasing waste, inducing potential conflicts of interest, and decreasing the quality of patient education. On the other hand, they have the potential to help those in financial need, to improve adherence and convenience, and to expose patients to better drugs. Although some academic centers have banned drug samples altogether, many academic and private practices continue to distribute drug samples. Given the controversy of the topic, physicians who wish to distribute drug samples must do so in an ethical manner. We believe, when handled properly, drug sampling can be used in an ethical manner. Copyright © 2012 Elsevier Inc. All rights reserved.

Cooperative Analysis of National Bureau of Standards Standard Sample Number 30e (Or-V Steel)

DTIC Science & Technology

1956-04-10

üatioual ?ßureau of g)tanbarbÄ Certificate of ^nalp^ etf Standard Sample 30E Chromium-Vanadium Steel kf mMmJmSmm ««UM ikco^ KMaQ« •• I N<IS<UI H4 «• a... stock , and cannot be furnished. If convenient, we would like to hare reports by February 20. Please include with your report a brief outline of the

Portable gas chromatograph mass spectrometer for on-site chemical analyses

DOEpatents

Haas, Jeffrey S.; Bushman, John F.; Howard, Douglas E.; Wong, James L.; Eckels, Joel D.

2002-01-01

A portable, lightweight (approximately 25 kg) gas chromatograph mass spectrometer, including the entire vacuum system, can perform qualitative and quantitative analyses of all sample types in the field. The GC/MS has a conveniently configured layout of components for ease of serviceability and maintenance. The GC/MS system can be transported under operating or near-operating conditions (i.e., under vacuum and at elevated temperature) to reduce the downtime before samples can be analyzed on-site.

Dried blood spot assay for the quantification of phenytoin using Liquid Chromatography-Mass Spectrometry.

PubMed

Villanelli, Fabio; Giocaliere, Elisa; Malvagia, Sabrina; Rosati, Anna; Forni, Giulia; Funghini, Silvia; Shokry, Engy; Ombrone, Daniela; Della Bona, Maria Luisa; Guerrini, Renzo; la Marca, Giancarlo

2015-02-02

Phenytoin (PHT) is one of the most commonly used anticonvulsant drugs for the treatment of epilepsy and bipolar disorders. The large amount of plasma required by conventional methods for drug quantification makes mass spectrometry combined with dried blood spot (DBS) sampling crucial for pediatric patients where therapeutic drug monitoring or pharmacokinetic studies may be difficult to realize. DBS represents a new convenient sampling support requiring minimally invasive blood drawing and providing long-term stability of samples and less expensive shipment and storage. The aim of this study was to develop a LC-MS/MS method for the quantification of PHT on DBS. This analytical method was validated and gave good linearity (r(2)=0.999) in the range of 0-100mg/l. LOQ and LOD were 1.0mg/l and 0.3mg/l, respectively. The drug extraction from paper was performed in a few minutes using a mixture composed of organic solvent for 80%. The recovery ranged from 85 to 90%; PHT in DBS showed to be stable at different storage temperatures for one month. A good correlation was also obtained between PHT plasma and DBS concentrations. This method is both precise and accurate and appears to be particularly suitable to monitor treatment with a simple and convenient sample collection procedure. Copyright © 2014 Elsevier B.V. All rights reserved.

A meta-analysis of the social communication questionnaire: Screening for autism spectrum disorder.

PubMed

Chesnut, Steven R; Wei, Tianlan; Barnard-Brak, Lucy; Richman, David M

2017-11-01

The current meta-analysis examines the previous research on the utility of the Social Communication Questionnaire as a screening instrument for autism spectrum disorder. Previously published reports have highlighted the inconsistencies between Social Communication Questionnaire-screening results and formal autism spectrum disorder diagnoses. The variations in accuracy resulted in some researchers questioning the validity of the Social Communication Questionnaire. This study systematically examined the accuracy of the Social Communication Questionnaire as a function of the methodological decisions made by researchers screening for autism spectrum disorder over the last 15 years. Findings from this study suggest that the Social Communication Questionnaire is an acceptable screening instrument for autism spectrum disorder (area under the curve = 0.885). Variations in methodological decisions, however, greatly influenced the accuracy of the Social Communication Questionnaire in screening for autism spectrum disorder. Of these methodological variations, using the Current instead of the Lifetime version of the Social Communication Questionnaire resulted in the largest detrimental effect ( d = -3.898), followed by using the Social Communication Questionnaire with individuals younger than 4 years of age ( d = -2.924) and relying upon convenience samples ( d = -4.828 for clinical samples, -2.734 for convenience samples, and -1.422 for community samples). Directions for future research and implications for using the Social Communication Questionnaire to screen for autism spectrum disorder are discussed.

Time-in-a-bottle (TIAB): a longitudinal, correlational study of patterns, potential predictors, and outcomes of immunosuppressive medication adherence in adult kidney transplant recipients.

PubMed

Russell, Cynthia L; Ashbaugh, Catherine; Peace, Leanne; Cetingok, Muammer; Hamburger, Karen Q; Owens, Sarah; Coffey, Deanna; Webb, Andrew W; Hathaway, Donna; Winsett, Rebecca P; Madsen, Richard; Wakefield, Mark R

2013-01-01

This study examined patterns, potential predictors, and outcomes of immunosuppressive medication adherence in a convenience sample of 121 kidney transplant recipients aged 21 yr or older from three kidney transplant centers using a theory-based, descriptive, correlational, longitudinal design. Electronic monitoring was conducted for 12 months using electronic monitoring. Participants were persistent in taking their immunosuppressive medications, but execution, which includes both taking and timing, was poor. Older age was the only demographic variable associated with medication adherence (r = 0.25; p = 0.005). Of the potential predictors examined, only medication self-efficacy was associated with medication non-adherence, explaining about 9% of the variance (r = 0.31, p = 0.0006). The few poor outcomes that occurred were not significantly associated with medication non-adherence, although the small number of poor outcomes may have limited our ability to detect a link. Future research should test fully powered, theory-based, experimental interventions that include a medication self-efficacy component. © 2013 John Wiley & Sons A/S.

Time-in-a-Bottle (TIAB): A Longitudinal, Correlational Study of Patterns, Potential Predictors, and Outcomes of Immunosuppressive Medication Adherence in Adult Kidney Transplant Recipients

PubMed Central

Russell, Cynthia L.; Ashbaugh, Catherine; Peace, Leanne; Cetingok, Muammer; Hamburger, Karen Q.; Owens, Sarah; Coffey, Deanna; Webb, Andrew; Hathaway, Donna; Winsett, Rebecca P.; Madsen, Richard; Wakefield, Mark R.

2013-01-01

This study examined patterns, potential predictors, and outcomes of immunosuppressive medication adherence in a convenience sample of 121 kidney transplant recipients aged 21 years or older from three kidney transplant centers using a theory-based, descriptive, correlational, longitudinal design. Electronic monitoring was conducted for 12 months using the Medication Event Monitoring System. Participants were persistent in taking their immunosuppressive medications, but execution, which includes both taking and timing, was poor. Older age was the only demographic variable associated with medication adherence (r = 0.25; p = 0.005). Of the potential predictors examined, only medication self-efficacy was associated with medication non-adherence, explaining about 9% of the variance (r = 0.31, p = 0.0006). The few poor outcomes that occurred were not significantly associated with medication non-adherence, although the small number of poor outcomes may have limited our ability to detect a link. Future research should test fully powered, theory-based, experimental interventions that include a medication self-efficacy component. PMID:24093614

Comparative evaluation of three different ELISA assays and HPLC-ESI-ITMS/MS for the analysis of Nε-carboxymethyl lysine in food samples.

PubMed

Gómez-Ojeda, Armando; Jaramillo-Ortíz, Sarahi; Wrobel, Katarzyna; Wrobel, Kazimierz; Barbosa-Sabanero, Gloria; Luevano-Contreras, Claudia; de la Maza, Maria Pia; Uribarri, Jaime; Del Castillo, Ma Dolores; Garay-Sevilla, Ma Eugenia

2018-03-15

N ε -carboxymethyl-lysine (CML) is measured in food, but there is a controversy concerning the most convenient yet reliable method(s) for this task. This work compares three different ELISA assays and HPLC-ESI-ITMS/MS for the analysis of CML in several food items. The four methods showed the same decreasing order of CML concentration: beef, bacon>chicken > fish>dairy products>grain products>fruits/vegetables. HPLC-ESI-ITMS/MS results highly correlated with those obtained by ELISA performed with monoclonal CML-antibody (β=0.98, p<0.0001) whereas My Bio Source® kit results were not correlated with those provided by Lamider®. Small differences of CML concentrations in food items prepared by different culinary treatment were clearly distinguished by HPLC-ESI-ITMS/MS, but could not always be detected by ELISA. This work demonstrates a reasonable relationship between CM determined by ELISA and HPLC-ESI-ITMS/MS and therefore supports the implementation of ELISA in food CML/AGEs screening. Copyright © 2017. Published by Elsevier Ltd.

Using computer-assisted learning to engage diverse learning styles in understanding business management principles.

PubMed

Frost, Mary E; Derby, Dustin C; Haan, Andrea G

2013-01-01

Objective : Changes in small business and insurance present challenges for newly graduated chiropractors. Technology that reaches identified, diverse learning styles may assist the chiropractic student in business classes to meet course outcomes better. Thus, the purpose of our study is to determine if the use of technology-based instructional aids enhance students' mastery of course learning outcomes. Methods : Using convenience sampling, 86 students completed a survey assessing course learning outcomes, learning style, and the helpfulness of lecture and computer-assisted learning related to content mastery. Quantitative analyses occurred. Results : Although respondents reported not finding the computer-assisted learning as helpful as the lecture, significant relationships were found between pre- and post-assisted learning measures of the learning outcomes 1 and 2 for the visual and kinesthetic groups. Surprisingly, however, all learning style groups exhibited significant pre- and post-assisted learning appraisal relationships with learning outcomes 3 and 4. Conclusion : While evidence exists within the current study of a relationship between students' learning of the course content corollary to the use of technologic instructional aids, the exact nature of the relationship remains unclear.

Using computer-assisted learning to engage diverse learning styles in understanding business management principles.

PubMed

Frost, Mary E; Derby, Dustin C; Haan, Andrea G

2013-06-27

Objective : Changes in small business and insurance present challenges for newly graduated chiropractors. Technology that reaches identified, diverse learning styles may assist the chiropractic student in business classes to meet course outcomes better. Thus, the purpose of our study is to determine if the use of technology-based instructional aids enhance students' mastery of course learning outcomes. Methods : Using convenience sampling, 86 students completed a survey assessing course learning outcomes, learning style, and the helpfulness of lecture and computer-assisted learning related to content mastery. Quantitative analyses occurred. Results : Although respondents reported not finding the computer-assisted learning as helpful as the lecture, significant relationships were found between pre- and post-assisted learning measures of the learning outcomes 1 and 2 for the visual and kinesthetic groups. Surprisingly, however, all learning style groups exhibited significant pre- and post-assisted learning appraisal relationships with learning outcomes 3 and 4. Conclusion : While evidence exists within the current study of a relationship between students' learning of the course content corollary to the use of technologic instructional aids, the exact nature of the relationship remains unclear.

Analytical Devices Based on Direct Synthesis of DNA on Paper.

PubMed

Glavan, Ana C; Niu, Jia; Chen, Zhen; Güder, Firat; Cheng, Chao-Min; Liu, David; Whitesides, George M

2016-01-05

This paper addresses a growing need in clinical diagnostics for parallel, multiplex analysis of biomarkers from small biological samples. It describes a new procedure for assembling arrays of ssDNA and proteins on paper. This method starts with the synthesis of DNA oligonucleotides covalently linked to paper and proceeds to assemble microzones of DNA-conjugated paper into arrays capable of simultaneously capturing DNA, DNA-conjugated protein antigens, and DNA-conjugated antibodies. The synthesis of ssDNA oligonucleotides on paper is convenient and effective with 32% of the oligonucleotides cleaved and eluted from the paper substrate being full-length by HPLC for a 32-mer. These ssDNA arrays can be used to detect fluorophore-linked DNA oligonucleotides in solution, and as the basis for DNA-directed assembly of arrays of DNA-conjugated capture antibodies on paper, detect protein antigens by sandwich ELISAs. Paper-anchored ssDNA arrays with different sequences can be used to assemble paper-based devices capable of detecting DNA and antibodies in the same device and enable simple microfluidic paper-based devices.

An effective parameter optimization technique for vibration flow field characterization of PP melts via LS-SVM combined with SALS in an electromagnetism dynamic extruder

NASA Astrophysics Data System (ADS)

Xian, Guangming

2018-03-01

A method for predicting the optimal vibration field parameters by least square support vector machine (LS-SVM) is presented in this paper. One convenient and commonly used technique for characterizing the the vibration flow field of polymer melts films is small angle light scattering (SALS) in a visualized slit die of the electromagnetism dynamic extruder. The optimal value of vibration vibration frequency, vibration amplitude, and the maximum light intensity projection area can be obtained by using LS-SVM for prediction. For illustrating this method and show its validity, the flowing material is used with polypropylene (PP) and fifteen samples are tested at the rotation speed of screw at 36rpm. This paper first describes the apparatus of SALS to perform the experiments, then gives the theoretical basis of this new method, and detail the experimental results for parameter prediction of vibration flow field. It is demonstrated that it is possible to use the method of SALS and obtain detailed information on optimal parameter of vibration flow field of PP melts by LS-SVM.

An evaluation of the HemoCue for measuring haemoglobin in field studies in Jamaica.

PubMed Central

Hudson-Thomas, M.; Bingham, K. C.; Simmons, W. K.

1994-01-01

The HemoCue system utilizes the principle of oxidation of haemoglobin to hemiglobin by sodium nitrite and the subsequent conversion of hemiglobin to hemiglobinazide by sodium azide. The reagents for these reactions are contained within a small disposable microcuvette of approximately 10 microliters in volume. A venous or capillary sample is introduced into the microcuvette by capillary action and, after reaction with the reagents, the absorbance is read in the HemoCue photometer at 565 and 880 nm. The haemoglobin concentration is then displayed as a digital reading, in either g/dl or mmol/l in 15-45 seconds. We compared haemoglobin values obtained by the HemoCue system with those from the Coulter Counter S-Plus IV in 366 pregnant women in urban Jamaica, and found a highly significant correlation (r = 0.78, P < 0.01). However, because of the convenience and ease of use of this instrument and considering the relatively high cost, we recommend it for use only as a research tool in field studies where accurate and rapid haemoglobin determinations are required. PMID:8062400

Exploring National Surveillance for Health-Related Workplace Absenteeism: Lessons Learned From the 2009 Influenza A Pandemic

PubMed Central

Groenewold, Matthew R.; Konicki, Doris L.; Luckhaupt, Sara E.; Gomaa, Ahmed; Koonin, Lisa M.

2015-01-01

Background During the 2009 influenza A (H1N1) virus pandemic, the Centers for Disease Control and Prevention did a pilot study to test the feasibility of using national surveillance of workplace absenteeism to assess the pandemic’s impact on the workplace to plan for preparedness and continuity of operations and to contribute to health awareness during the emergency response. Methods Population-based and sentinel worksite approaches were used. Monthly measures of the 1-week prevalence of health-related absenteeism among full-time workers were estimated using nationally representative data from the Current Population Survey. Enhanced passive surveillance of absenteeism was conducted using weekly data from a convenience sample of sentinel worksites. Results Nationally, the pandemic’s impact on workplace absenteeism was small. Estimates of 1-week absenteeism prevalence did not exceed 3.7%. However, peak workplace absenteeism was correlated with the highest occurrence of both influenza-like illness and influenza-positive laboratory tests. Conclusions Systems for monitoring workplace absenteeism should be included in pandemic preparedness planning PMID:24618167

A Randomized, Controlled Trial of Wholistic Hybrid Derived From Eye Movement Desensitization and Reprocessing and Emotional Freedom Technique (WHEE) for Self-Treatment of Pain, Depression, and Anxiety in Chronic Pain Patients

PubMed Central

Benor, Daniel; Rossiter-Thornton, John; Toussaint, Loren

2016-01-01

In this pilot study, a convenience sample of 24 chronic pain patients (17 with chronic fatigue syndrome/fibromyalgia) were randomized into WHEE treatment and wait-list control groups for 6 weeks. Assessments of depression, anxiety, and pain were completed before, during, and at 1 and 3 months after treatment. Wait-listed patients then received an identical course of WHEE and assessments. WHEE decreased anxiety (P < .5) and depression (P < .05) compared with the control group. The wait-list-turned-WHEE assessments demonstrated decreased pain severity (P < .05) and depression (P < .04) but not pain interference or anxiety. WHEE appears a promising method for pain, anxiety, and depression in patients with chronic pain, compared to standard medical care alone. Though a small pilot study, the present results suggest that further research appears warranted. An incidental finding was that a majority of patients with chronic pain had suffered psychological trauma in childhood and/or adulthood. PMID:27432773

A primary health care curriculum in action: the lived experience of primary health care nurses in a school of nursing in the Philippines: a phenomenological study.

PubMed

Arthur, David; Drury, John; Sy-Sinda, Maria Teresita; Nakao, Ramonita; Lopez, Arsenia; Gloria, Grace; Turtal, Rowena; Luna, Evelyn

2006-01-01

Primary health care (PHC) nursing is widely practiced in the Philippines yet little is published about the nurses working in this field nor by these nurses. This paper describes a PHC nursing curriculum conducted in an island in the south of the Philippines and examines the experience of nurses working as faculty and simultaneously providing service to the local community. Data were collected from a convenience sample of faculty by interview and analysed using Huserrlian (descriptive) phenomenology and Colaizzi's method of data analysis. From 102 formulated meanings emerged four theme clusters: teaching PHC; external influences; the working reality and practicing PHC, and these are presented with exemplars from the interviews. The data gives a clear impression of the experience of implementing PHC and working with small communities and highlights the educational and clinical issues inherent in this unique model. The insights gained from the analysis of the interviews are contrasted with current literature and recommendations for future research are made.

Human milk use in Australian hospitals, 1949-1985.

PubMed

Thorley, Virginia

2012-07-01

This paper will draw mainly on the experiences of fourteen women to explore the use of expressed human milk by hospitals in Australia from the postwar period through to 1985. The purpose is to provide a snapshot of common practices before the decline of human milk banking and other uses of expressed breastmilk in Australian hospitals, thus providing a source for future comparison against the more rigorous, uniform practices being instituted in the new milk banks of the early-21st century. The ten mothers included were a convenience sample drawn from the author's networks, with recruitment continuing till a range of hospital types and a majority of states were included. Three of the mothers also had experience as trainee midwives and midwives, and four midwives contributed their experiences as staff members, only. The hospitals ranged from large teaching hospitals to small private hospitals and were in metropolitan, regional and country locations. The practices included routine expression and expression for specific purposes, whether for the mother's own baby or to donate. Some hospitals pooled the donor milk for premature or sick babies.

Fundamental characteristics of input waste of small MSW incinerators in Korea.

PubMed

Choi, Ki-In; Lee, Suk-Hui; Lee, Dong-Hoon; Osako, Masahiro

2008-11-01

Waste incineration in a small incinerator is a simple and convenient way of treating waste discharged from small areas or from large facilities and buildings such as business centers, marketplaces, factories, and military units. Despite their ostensible advantages, however, many small incinerators frequently suffer from serious problems, e.g., unsystematic waste feeding, unstable combustion, deficient air pollution control devices, and consequently, environmental pollution. To obtain a better understanding of the characterization of wastes in small incinerators, we investigated a series of fundamental characteristics, i.e., physical composition, bulk density, proximate and ultimate analysis, potential energy content, and so on. The main waste components in small incinerators were identified as paper and plastic; the proportion of food waste was less than that in large incinerators. Especially, a low ratio of food waste had a strong influence on other waste characteristics, e.g., lower moisture content and bulk density, and higher potential energy. On the other hand, in contrast with that of HCl, there was no distinguishable linear relationship between Cl content in waste and PCDD/DF concentration in combustion gas.

Birefringence insensitive optical coherence domain reflectometry system

DOEpatents

Everett, Matthew J.; Davis, Joseph G.

2002-01-01

A birefringence insensitive fiber optic optical coherence domain reflectometry (OCDR) system is provided containing non-polarization maintaining (non-PM) fiber in the sample arm and the reference arm without suffering from signal degradation caused by birefringence. The use of non-PM fiber significantly reduces the cost of the OCDR system and provides a disposable or multiplexed section of the sample arm. The dispersion in the reference arm and sample arm of the OCDR system are matched to achieve high resolution imaging. This system is useful in medical applications or for non-medical in situ probes. The disposable section of non-PM fiber in the sample arm can be conveniently replaced when contaminated by a sample or a patient.

Detection of small-size solder ball defects through heat conduction analysis

NASA Astrophysics Data System (ADS)

Zhou, Xiuyun; Chen, Yaqiu; Lu, Xiaochuan

2018-02-01

Aiming to solve the defect detection problem of a small-size solder ball in the high density chip, heat conduction analysis based on eddy current pulsed thermography is put forward to differentiate various defects. With establishing the 3D finite element model about induction heating, defects such as cracks and void can be distinguished by temperature difference resulting from heat conduction. Furthermore, the experiment of 0.4 mm-diameter solder balls with different defects is carried out to prove that crack and void solder can be distinguished. Three kinds of crack length on a gull-wing pin are selected, including 0.24 mm, 1.2 mm, and 2.16 mm, to verify that the small defect can be discriminated. Both the simulation study and experiment result show that the heat conduction analysis method is reliable and convenient.

A comparison of quality and utilization problems in large and small group practices.

PubMed

Gleason, S C; Richards, M J; Quinnell, J E

1995-12-01

Physicians practicing in large, multispecialty medical groups share an organizational culture that differs from that of physicians in small or independent practices. Since 1980, there has been a sharp increase in the size of multispecialty group practice organizations, in part because of increased efficiencies of large group practices. The greater number of physicians and support personnel in a large group practice also requires a relatively more sophisticated management structure. The efficiencies, conveniences, and management structure of a large group practice provide an optimal environment to practice medicine. However, a search of the literature found no data linking a large group practice environment to practice outcomes. The purpose of the study reported in this article was to determine if physicians in large practices have fewer quality and utilization problems than physicians in small or independent practices.

[Advances in Liquid Biopsy and its Clinical Application in the Diagnosis 
and Treatment of Non-small Cell Lung Cancer].

PubMed

Zheng, Difan; Chen, Haiquan

2016-06-20

With the advances of technology, great progresses have been made in liquid biopsy in recent years. Liquid biopsy is currently playing a more and more important role in early diagnosis and treatment of cancer. Compared with traditional tissue biopsy, liquid biopsy is more popular in clinical practice due to its non-invasiveness, convenience and high repeatability. It has huge potential in the future. This review introduces circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) as the most important objects in liquid biopsy, mainly focusing on their history, biological characteristics, detection technologies, limitations and applications in non-small cell lung cancer.

Personal computer study of finite-difference methods for the transonic small disturbance equation

NASA Technical Reports Server (NTRS)

Bland, Samuel R.

1989-01-01

Calculation of unsteady flow phenomena requires careful attention to the numerical treatment of the governing partial differential equations. The personal computer provides a convenient and useful tool for the development of meshes, algorithms, and boundary conditions needed to provide time accurate solution of these equations. The one-dimensional equation considered provides a suitable model for the study of wave propagation in the equations of transonic small disturbance potential flow. Numerical results for effects of mesh size, extent, and stretching, time step size, and choice of far-field boundary conditions are presented. Analysis of the discretized model problem supports these numerical results. Guidelines for suitable mesh and time step choices are given.

A robust variable sampling time BLDC motor control design based upon μ-synthesis.

PubMed

Hung, Chung-Wen; Yen, Jia-Yush

2013-01-01

The variable sampling rate system is encountered in many applications. When the speed information is derived from the position marks along the trajectory, one would have a speed dependent sampling rate system. The conventional fixed or multisampling rate system theory may not work in these cases because the system dynamics include the uncertainties which resulted from the variable sampling rate. This paper derived a convenient expression for the speed dependent sampling rate system. The varying sampling rate effect is then translated into multiplicative uncertainties to the system. The design then uses the popular μ-synthesis process to achieve a robust performance controller design. The implementation on a BLDC motor demonstrates the effectiveness of the design approach.

A Robust Variable Sampling Time BLDC Motor Control Design Based upon μ-Synthesis

PubMed Central

Yen, Jia-Yush

2013-01-01

The variable sampling rate system is encountered in many applications. When the speed information is derived from the position marks along the trajectory, one would have a speed dependent sampling rate system. The conventional fixed or multisampling rate system theory may not work in these cases because the system dynamics include the uncertainties which resulted from the variable sampling rate. This paper derived a convenient expression for the speed dependent sampling rate system. The varying sampling rate effect is then translated into multiplicative uncertainties to the system. The design then uses the popular μ-synthesis process to achieve a robust performance controller design. The implementation on a BLDC motor demonstrates the effectiveness of the design approach. PMID:24327804

African-American Undergraduates' Perceptions and Attributions of Child Sexual Abuse

ERIC Educational Resources Information Center

Hestick, Henrietta; Perrino, Carrol S.

2009-01-01

This study examined perceptions of child sexual abuse and attributions of responsibility in a cross-sectional convenience sample of 384 African-American undergraduates using a scenario manipulating the age of the victim, gender of the victim, and gender of the perpetrator. Multiple interactions of respondent, victim, and perpetrator gender on…

Verbal versus Numerical Probabilities: Does Format Presentation of Probabilistic Information regarding Breast Cancer Screening Affect Women's Comprehension?

ERIC Educational Resources Information Center

Vahabi, Mandana

2010-01-01

Objective: To test whether the format in which women receive probabilistic information about breast cancer and mammography affects their comprehension. Methods: A convenience sample of 180 women received pre-assembled randomized packages containing a breast health information brochure, with probabilities presented in either verbal or numeric…

Spirituality and the Events of September 11: A Preliminary Study

ERIC Educational Resources Information Center

Briggs, Michele Kielty; Apple, Kevin J.; Aydlett, Ann E.

2004-01-01

Personal crises have been associated with spiritual growth. Sparked by the global response to the crisis of September 11, 2001, this study examined the relationship of spirituality and the September 11 tragedy using a sample of convenience from a college student population. This preliminary study used an experimental design to examine various…

Interpersonal Skills and Facebook® Use among College Students

ERIC Educational Resources Information Center

Rhodes, Darson L.; Sniatecki, Jessica L.; Rocco, Mary; Todd, Lauren

2015-01-01

The use of Facebook® among college students is prevalent, and its relationship with interpersonal skills is unknown. A cross-sectional design study using a convenience sample of undergraduate students enrolled in one of four sections of an upper-level nutrition course at a Northeastern, public university was conducted to investigate this…

Postpartum Mental State of Mothers of Twins

ERIC Educational Resources Information Center

Brantmüller, Éva; Gyúró, Mónika; Galgán, Kitti; Pakai, Annamária

2016-01-01

Twin birth is a relevant risk factor for postnatal depression (PND). The primary objective of our study is to reveal the prevalence of suspected cases of depression and to identify some background factors among mothers of twins. We applied convenience sampling method within a retrospective, quantitative study among mothers given birth to twins for…

Study on Instructional Paradigms of Virtual Education in Pakistan: A Learners' Perspective

ERIC Educational Resources Information Center

Hussain, Irshad

2012-01-01

The present study is aimed at examining instructional paradigms of virtual education in Pakistan. The population of the study consisted of learners from Master of Business Administration (MBA) Program at Virtual University (VU) of Pakistan. The researcher adopted convenient sampling technique and collected data from 600 learners through five-point…

Take It or Leave It: Students' Attitudes about Research Methods

ERIC Educational Resources Information Center

Wisecup, Allison K.

2017-01-01

This study employs a cross-sectional design to explore sociology majors' attitudes toward research methods. Survey data from a convenience sample of students enrolled in 16 departments are used to compare the attitudes of students who have and have not completed a research methods course. Despite consistent anecdotal claims that students harbor…

School Social Workers' Perceived Efficacy at Tasks Related to Curbing Suspension and Undesirable Behaviors

ERIC Educational Resources Information Center

Teasley, Martell L.; Miller, Christina R.

2011-01-01

This study explores school social workers' perceptions of their ability to successfully engage in practice tasks that reduce the likelihood of school suspension and undesirable behaviors among racial and ethnic groups within diverse geographical locations (urban, suburban, and rural). Using survey research methods with a convenience sample, 201…

The Effect of an Instructional Intervention on Elementary Students' Science Process Skills

ERIC Educational Resources Information Center

Durmaz, Hüsnüye; Mutlu, Seçkin

2017-01-01

The authors' aim was to investigate the effects of the instructional intervention on science processes skills (SPSs) of seventh-grade students. The study was designed as nonequivalent control-group pretest-posttest, and it was carried out with 43 students. Participants were chosen according to the convenient sampling method. The authors collected…

Testing the "Learning Journey" of MSW Students in a Rural Program

ERIC Educational Resources Information Center

Wall, Misty L.; Rainford, Will

2013-01-01

Using a quasi-experimental one-group, pretest-posttest design with non-random convenience sampling, the researchers assessed 61 advanced standing MSW students who matriculated at a rural intermountain Northwest school of social work. Changes in students' knowledge and attitudes toward lesbian, gay, and bisexual (LGB) people were measured using…

Assessing the Attitudes of Administrators to Include Students with Disabilities

ERIC Educational Resources Information Center

Abernathy, Frederick Douglas

2012-01-01

The purpose of this research was to assess the attitudes of administrators in a medium sized school district in the Southeastern region of the United States. The researcher used a quantitative descriptive comparative pre-test and post-test design with a convenience sampling of the district administrators. There were 21 administrators at the…

The Fatherhood Scale

ERIC Educational Resources Information Center

Dick, Gary L.

2004-01-01

This article reports on the initial validation of the Fatherhood Scale (FS), a 64-item instrument designed to measure the type of relationship a male adult had with his father while growing up. The FS was validated using a convenience sample of 311 males. The assessment packet contained a demographic form, the Conflict Tactics Scale (2),…

Association between Adult Romantic Attachment Styles and Family-of-Origin Expressive Atmosphere

ERIC Educational Resources Information Center

Smith, Shannon D.; Ng, Kok-Mun

2009-01-01

This study examined the associations between attachment quality and perceived family-of-origin expressive atmosphere (FOEA) in a convenience sample of 279 participants. Multivariate analysis of variance (MAN-OVA) was used to examine the associations between attachment style and FOEA, and hierarchical regression was used to analyze FOEA as a…

Distinguishing between Positive and Negative Social Bonding in Problem Drinking among College Students

ERIC Educational Resources Information Center

Zullig, Keith J.; Young, Michael; Hussain, Mohammad

2010-01-01

Background: To reduce problem drinking, interventions must be directed toward those factors associated with problem drinking. Purpose: This study examined how perceptions of the role of alcohol related to problem drinking among a convenience sample of 301 college students. Methods: Fifteen items concerned with drinking behavior or perceptions…

Depressive Symptoms in Adolescents Living in Rural America

ERIC Educational Resources Information Center

Peden, Ann R.; Reed, Deborah B.; Rayens, Mary Kay

2005-01-01

Purpose: The purposes of this pilot study were to examine prevalence of depressive symptoms among rural adolescents and identify related social and environmental variables. Methods: A convenience sample of 299 14- to 18-year-old agriculture class students at 5 rural high schools in Kentucky and Iowa completed a survey that included demographic…

The Economic Value of Career Counseling Services for College Students in South Korea

ERIC Educational Resources Information Center

Choi, Bo Young; Lee, Ji Hee; Kim, Areum; Kim, Boram; Cho, Daeyeon; Lee, Sang Min

2013-01-01

This study investigated college students' perception of the monetary value of career counseling services by using the contingent valuation method. The results of a multivariate survival analysis based on interviews with a convenience sample of 291 undergraduate students in South Korea indicate that, on average, participants' expressed willingness…

The Effect of a Recessionary Economy on Food Choice: Implications for Nutrition Education

ERIC Educational Resources Information Center

Miller, Carla K.; Branscum, Paul

2012-01-01

Objective: To determine the effect of an economic recession on food choice behaviors. Design: A qualitative study using semistructured, in-depth interviews followed by completion of a nutrition knowledge questionnaire and the Food Choice Questionnaire was conducted. Setting and Participants: A convenience sample from a metropolitan city in the…

How to Help Parents Pack Better Preschool Sack Lunches: Advice from Parents for Educators

ERIC Educational Resources Information Center

Sweitzer, Sara J.; Briley, Margaret E.; Roberts-Gray, Cindy; Hoelscher, Deanna M.; Staskel, Deanna M.; Almansour, Fawaz D.

2011-01-01

Objectives: This exploratory study obtained parent suggestions about messages and activities to guide parents to pack healthful sack lunches for preschool-aged children. Methods: A facilitator conducted group interviews using a modified nominal group technique with a convenience sample of parents who pack daily lunches for their children.…

Finding Pearls: Psychometric Reevaluation of the Simpson-Troost Attitude Questionnaire (STAQ)

ERIC Educational Resources Information Center

Owen, Steven V.; Toepperwein, Mary Anne; Marshall, Carolyn E.; Lichtenstein, Michael J.; Blalock, Cheryl L.; Liu, Yan; Pruski, Linda A.; Grimes, Kandi

2008-01-01

The Simpson-Troost Attitude Questionnaire (STAQ) was developed as part of a study to assess adolescent commitment to and achievement in science. For this psychometric reappraisal of the 57-item STAQ, data were analyzed from a convenience sample of 1,754 secondary students. Confirmatory and exploratory factor analyses were applied, and results…

Validity of a Checklist for the Design, Content, and Instructional Qualities of Children's Books

ERIC Educational Resources Information Center

Çer, Erkan; Sahin, Ertugrul

2016-01-01

The purpose of this study was to develop a checklist whose validity has been tested in assessing children's books. Participants consisted of university students who had taken a course in children's literature. They were selected through convenience sampling and randomly assigned into experimental and control groups. Participants in the…

Agricultural Trainees' and Extension Personnel's Attitudes toward HIV/AIDS: Implications for Extension Service Delivery in Nigeria

ERIC Educational Resources Information Center

Ladebo, Olugbenga Jelil

2004-01-01

This study examined the public stereotypes of HIV-positive persons and the relationship with knowledge about the disease. 164 extension personnel and a convenience sample of 250 undergraduate students from an Agricultural Development Programme and an Agricultural University respectively, were interviewed for the study. Both institutions were…

A Study of Self-Esteem in Adopted Non-adopted Adolescents.

ERIC Educational Resources Information Center

Steward, Robbie J.; Lynn, Betty Jane

This study tested the hypothesis that adopted adolescents have lower self-esteem than do non-adopted adolescents. Male and female students (N=159) between the ages of 18 and 22 were conveniently sampled from college undergraduate populations. Forty-four of the participants reported adoptive status. Each participant completed the Coopersmith…

Using Chemistry Simulations: Attention Capture, Selective Amnesia and Inattentional Blindness

ERIC Educational Resources Information Center

Rodrigues, Susan

2011-01-01

Twenty-one convenience sample student volunteers aged between 14-15 years worked in pairs (and one group of three) with two randomly allocated high quality conceptual (molecular level) and operational (mimicking wet labs) simulations. The volunteers were told they had five minutes to play, repeat, review, restart or stop the simulation, which in…

Parental Perceptions of the Rural School's Role in Addressing Childhood Obesity

ERIC Educational Resources Information Center

Stalter, Ann M.; Kaylor, Marybeth; Steinke, Jessica D.; Barker, Rosanta M.

2011-01-01

This study employed cross-sectional, descriptive design with convenience sampling to explore rural parent perceptions of child obesity, use of Body Mass Index (BMI) in schools, preferences for receipt of BMI information and, the rural school's role in obesity prevention/treatment. The survey "Parental Perceptions of BMI and Obesity in the…

Improving the Quality of Evidence-Based Writing Entries in Electronic Portfolios

ERIC Educational Resources Information Center

Denton, David W.

2012-01-01

The problem investigated in this study was whether entries written to an electronic portfolio by preservice teachers improved in quality after an intervention was deployed. The study also compared portfolio metadata to writing quality scores to determine whether there was a relationship. Participants included a convenience sample of 11…

Knowledge of Metabolic Syndrome in Chinese Adults: Implications for Health Education

ERIC Educational Resources Information Center

Lo, Sally Wai Sze; Chair, Sek Ying; Lee, Iris Fung Kam

2016-01-01

Objective: The objective of this study was to assess knowledge of metabolic syndrome (MS) among Chinese adults and provide directions for designing healthcare promotion schemes for improving MS awareness in the community. Design: The study adopted a cross-sectional design and a convenience sampling method. Method: Chinese adults aged 18-65 years…

Instructional Practices: A Qualitative Study on the Response to Common Core Standardized Testing

ERIC Educational Resources Information Center

Hightower, Gabrielle

2017-01-01

The purpose of this qualitative study was to examine the instructional practices implemented by Tennessee elementary teachers in response to Common Core Standardized Testing. This research study utilized a basic qualitative method that included a purposive and convenient sampling. This qualitative study focused on face-to-face interviews, phone…

Posttraumatic stress and functional impairment in Kenyan children following the 1998 American Embassy bombing.

PubMed

Pfefferbaum, Betty; North, Carol S; Doughty, Debby E; Gurwitch, Robin H; Fullerton, Carol S; Kyula, Jane

2003-04-01

This study examined a convenience sample of 562 Nairobi school children exposed to the 1998 bombing of the American Embassy in Nairobi, Kenya. Posttraumatic stress reactions to the bombing were related to posttraumatic stress reactions to other trauma and to peritraumatic reaction. Self-reported functional impairment was minimal.

Factors Contributing to the Uptake and Maintenance of Regular Exercise Behaviour in Emerging Adults

ERIC Educational Resources Information Center

Langdon, Jody; Johnson, Chad; Melton, Bridget

2017-01-01

Objective: To identify the influence of parental autonomy support, basic need satisfaction and motivation on emerging adults' physical activity level and exercise behaviours. Design: Cross-sectional survey. Setting: This study convenience-sampled approximately 435 college students identified as emerging adults--aged 18-25 years, who did not have a…

Classroom Composition and Racial Differences in Opportunities to Learn

ERIC Educational Resources Information Center

Minor, Elizabeth Covay

2015-01-01

Black and White advanced math students leave high school with disparate math skills. One possible explanation is that minority students are exposed to different learning opportunities, even when they are taking classes with the same title. Using a convenience sample of the Mathematics Survey of the Enacted Curriculum (SEC), this study found that…

Housing and Living Arrangements of South Asian Immigrant Seniors in Edmonton, Alberta

ERIC Educational Resources Information Center

Ng, Cheuk Fan; Northcott, Herbert C.; Abu-Laban, Sharon McIrvin

2007-01-01

The Canadian population is aging and becoming more ethnically diverse. This paper focuses on South Asian immigrant seniors and examines differences in housing and living arrangements among seniors who immigrated at different life stages. We interviewed a convenience sample of 161 immigrant seniors of South Asian descent in Edmonton, Alberta, to…

Multiple Health Behaviors and Psychological Well-Being of Chinese Female Undergraduate Students

ERIC Educational Resources Information Center

Bian, Hui; Wu, Jingjin; Li, Yan; Largo-Wight, Erin

2012-01-01

This study examined Chinese female college students' multiple health behaviors, their quality of life, and mental and psychological well-being and compared that with American counterparts. A convenience sample of 293 female undergraduates participated in the study during spring 2010, in Eastern China. A traditional self-report paper-pencil…

Development and Validation of the College Tobacco Survey.

ERIC Educational Resources Information Center

Ott, Carol H.; Cashin, Susan E.; Altekruse, Michael

2005-01-01

The authors report on the development and assessment of an instrument to measure baseline campus cigarette use and outcomes from prevention programs, including those using a social norms approach combined with environmental policy change. They administered the 37-item College Tobacco Survey (CTS) to a convenience sample of 1,279 college students…

Comparison of Cursive Handwriting Instruction Programs among Students without Identified Problems

ERIC Educational Resources Information Center

Shimel, Kristin; Candler, Catherine; Neville-Smith, Marsha

2009-01-01

The purpose of this study was to compare the effects of cursive handwriting programs in improving letter legibility and form in third-grade students without identified handwriting problems. Four months into the school year, cursive handwriting was assessed for a sample of convenience of 50 third-grade students. Subsequently, students received…

Assessing the Efficacy of a School Health Education Advocacy Lesson with College Students

ERIC Educational Resources Information Center

Wallen, Michele; Chaney, Beth H.; Birch, David A.

2012-01-01

Purpose: The researchers evaluated the efficacy of an advocacy lesson to assess change in intentions to advocate for school health education. This study also measured changes in participants' understanding the importance of school health education and perceived effectiveness in applying advocacy skills. Methods: A convenience sample of college…

The Learning Styles and Multiple Intelligences of EFL College Students in Kuwait

ERIC Educational Resources Information Center

Alrabah, Sulaiman; Wu, Shu-hua; Alotaibi, Abdullah M.

2018-01-01

The study aimed to investigate the learning styles and multiple intelligences of English as foreign language (EFL) college-level students. "Convenience sampling" (Patton, 2015) was used to collect data from a population of 250 students enrolled in seven different academic departments at the College of Basic Education in Kuwait. The data…

Subjective Effect of September 11, 2001 among Pregnant Women: Is Cumulative History of Interpersonal Violence Important?

ERIC Educational Resources Information Center

Lewis, Marilyn W.; Cavanagh, Paul K.; Ahn, Grace; Yoshioka, Marianne R.

2008-01-01

Prior history of trauma may sensitize individuals to subsequent trauma, including terrorist attacks. Using a convenience sample of secondary, cross-sectional data, pregnant women were grouped based on lifetime interpersonal violence history. Cumulative risk theory was used to evaluate the association of lifetime interpersonal violence history and…