Test-Retest Repeatability of Myocardial Blood Flow Measurements using Rubidium-82 Positron Emission Tomography

NASA Astrophysics Data System (ADS)

Efseaff, Matthew

Rubidium-82 positron emission tomography (PET) imaging has been proposed for routine myocardial blood flow (MBF) quantification. Few studies have investigated the test-retest repeatability of this method. Same-day repeatability of rest MBF imaging was optimized with a highly automated analysis program using image-derived input functions and a dual spillover correction (SOC). The effects of heterogeneous tracer infusion profiles and subject hemodynamics on test-retest repeatability were investigated at rest and during hyperemic stress. Factors affecting rest MBF repeatability included gender, suspected coronary artery disease, and dual SOC (p < 0.001). The best repeatability coefficient for same-day rest MBF was 0.20 mL/min/g using a six-minute scan-time, iterative reconstruction, dual SOC, resting rate-pressure-product (RPP) adjustment, and a left atrium image-derived input function. The serial study repeatabilities of the optimized protocol in subjects with homogeneous RPPs and tracer infusion profiles was 0.19 and 0.53 mL/min/g at rest and stress, and 0.95 for stress / rest myocardial flow reserve (MFR). Subjects with heterogeneous tracer infusion profiles and hemodynamic conditions had significantly less repeatable MBF measurements at rest, stress, and stress/rest flow reserve (p < 0.05).

Three-dimensional black-blood multi-contrast carotid imaging using compressed sensing: a repeatability study.

PubMed

Yuan, Jianmin; Usman, Ammara; Reid, Scott A; King, Kevin F; Patterson, Andrew J; Gillard, Jonathan H; Graves, Martin J

2018-02-01

The purpose of this work is to evaluate the repeatability of a compressed sensing (CS) accelerated multi-contrast carotid protocol at 3 T. Twelve volunteers and eight patients with carotid disease were scanned on a 3 T MRI scanner using a CS accelerated 3-D black-blood multi-contrast protocol which comprises T 1 w, T 2 w and PDw without CS, and with a CS factor of 1.5 and 2.0. The volunteers were scanned twice, the lumen/wall area and wall thickness were measured for each scan. Eight patients were scanned once, the inter/intra-observer reproducibility of the measurements was calculated. In the repeated volunteer scans, the interclass correlation coefficient (ICC) for the wall area measurement using a CS factor of 1.5 in PDw, T 1 w and T 2 w were 0.95, 0.81, and 0.97, respectively. The ICC for lumen area measurement using a CS factor of 1.5 in PDw, T 1 w and T 2 w were 0.96, 0.92, and 0.96, respectively. In patients, the ICC for inter/intra-observer measurements of lumen/wall area, and wall thickness were all above 0.81 in all sequences. The results show a CS accelerated 3-D black-blood multi-contrast protocol is a robust and reproducible method for carotid imaging. Future protocol design could use CS to reduce the scanning time.

Evaluation of the Repeatability and Accuracy of the Wideband Real-Ear-to-Coupler Difference.

PubMed

Vaisberg, Jonathan M; Folkeard, Paula; Pumford, John; Narten, Philipp; Scollie, Susan

2018-06-01

The real-ear-to-coupler difference (RECD) is an ANSI standardized method for estimating ear canal sound pressure level (SPL) thresholds and assisting in the prediction of real-ear aided responses. It measures the difference in dB between the SPL produced in the ear canal and the SPL produced in an HA-1 2-cc coupler by the same sound source. Recent evidence demonstrates that extended high-frequency bandwidth, beyond the hearing aid bandwidth typically measured, is capable of providing additional clinical benefit. The industry has, in turn, moved toward developing hearing aids and verification equipment capable of producing and measuring extended high-frequency audible output. As a result, a revised RECD procedure conducted using a smaller, 0.4-cc coupler, known as the wideband-RECD (wRECD), has been introduced to facilitate extended high-frequency coupler-based measurements up to 12.5 kHz. This study aimed to (1) compare test-retest repeatability between the RECD and wRECD and (2) measure absolute agreement between the RECD and wRECD when both are referenced to a common coupler. RECDs and wRECDs were measured bilaterally in adult ears by calculating the dB difference in SPL between the ear canal and coupler responses. Real-ear probe microphone measures were completed twice per ear per participant for both foam-tip and customized earmold couplings using the Audioscan Verifit 1 and Verifit 2 fitting systems, followed by measurements in the respective couplers. Twenty-one adults (mean age = 67 yr, range = 19-78) with typical aural anatomy (as determined by measures of impedance and otoscopy) participated in this study, leading to a sample size of 42 ears. Repeatability within RECD and wRECD was assessed for each coupling configuration using a repeated-measures analysis of variance (ANOVA) with test-retest and frequency as within-participants factors. Repeatability between the RECD and wRECD was assessed within each configuration using a repeated-measures ANOVA with test-retest, frequency, and coupler type as within-participants factors. Agreement between the RECD and wRECD was assessed for each coupling configuration using a repeated-measures ANOVA with RECD value, coupler type, and frequency as within-participants factors. Post hoc comparisons with Bonferroni corrections were used when appropriate to locate the frequencies at which differences occurred. A 3-dB criterion was defined to locate differences of clinical significance. Average absolute test-retest differences were within ±3 dB within each coupler and coupling configuration, and between the RECD and wRECD. The RECD and wRECD were in absolute agreement following HA-1-referenced transforms, with most frequencies agreeing within ±1 dB, except at 0.2 kHz for the earmold, and 0.2-0.25 kHz for the foam tip, where the average RECD exceeded the average wRECD by slightly >3 dB. Test-retest repeatability of the RECD (up to 8 kHz) and wRECD (up to 12.5 kHz) is acceptable and similar to previously reported data. The RECD and wRECD are referenced to different couplers, but can be rendered comparable with a simple transform, producing values that are in accordance with the ANSI S3.46-2013 standard. American Academy of Audiology.

[Direct human DNA damage by unfavorable environmental and climatic factors].

PubMed

Doroshtuk, N A; Postnov, A Iu; Doroshtuk, A D; Khasanova, E B; Konovalova, N V; Khesuani, Iu D; Osiaeva, M K; Rodnenkov, O V; Chazova, I E

2014-01-01

To study the impact of simulated climatic conditions of the 2010 summer in Moscow on the telomere repeats of chromosomes in human blood cells. The climatic conditions of July-August 2010 in Moscow were simulated at the Medical Technical Complex, Institute of Biomedical Problems, Russian Academy of Sciences. The relative length of the telomeric repeats of blood cell chromosomes from 6 apparently healthy volunteers was measured by quantitative real-time polymerase chain reaction. These conditions were ascertained to lead to a statistically significant decline in the length of telomere repeats in the terminal portions of chromosomes by 15%. Environmental changes and abnormal temperature rises may result in oxidative stress accompanied by telomere shortening, which can be, in turn, a factor of premature aging.

Social instigation and repeated aggressive confrontations in male Swiss mice: analysis of plasma corticosterone, CRF and BDNF levels in limbic brain areas.

PubMed

Fortes, Paula Madeira; Albrechet-Souza, Lucas; Vasconcelos, Mailton; Ascoli, Bruna Maria; Menegolla, Ana Paula; de Almeida, Rosa Maria M

2017-01-01

Agonistic behaviors help to ensure survival, provide advantage in competition, and communicate social status. The resident-intruder paradigm, an animal model based on male intraspecific confrontations, can be an ethologically relevant tool to investigate the neurobiology of aggressive behavior. To examine behavioral and neurobiological mechanisms of aggressive behavior in male Swiss mice exposed to repeated confrontations in the resident intruder paradigm. Behavioral analysis was performed in association with measurements of plasma corticosterone of mice repeatedly exposed to a potential rival nearby, but inaccessible (social instigation), or to 10 sessions of social instigation followed by direct aggressive encounters. Moreover, corticotropin-releasing factor (CRF) and brain-derived neurotrophic factor (BNDF) were measured in the brain of these animals. Control mice were exposed to neither social instigation nor aggressive confrontations. Mice exposed to aggressive confrontations exhibited a similar pattern of species-typical aggressive and non-aggressive behaviors on the first and the last session. Moreover, in contrast to social instigation only, repeated aggressive confrontations promoted an increase in plasma corticosterone. After 10 aggressive confrontation sessions, mice presented a non-significant trend toward reducing hippocampal levels of CRF, which inversely correlated with plasma corticosterone levels. Conversely, repeated sessions of social instigation or aggressive confrontation did not alter BDNF concentrations at the prefrontal cortex and hippocampus. Exposure to repeated episodes of aggressive encounters did not promote habituation over time. Additionally, CRF seems to be involved in physiological responses to social stressors.

Factors Affecting Two Types of Memory Specificity: Particularization of Episodes and Details.

PubMed

Willén, Rebecca M; Granhag, Pär Anders; Strömwall, Leif A

2016-01-01

Memory for repeated events is relevant to legal investigations about repeated occurrences. We investigated how two measures of specificity (number of events referred to and amount of detail reported about the events) were influenced by interviewees' age, number of experienced events, interviewer, perceived unpleasantness, and memory rehearsal. Transcribed narratives consisting of over 40.000 utterances from 95 dental patients, and the corresponding dental records, were studied. Amount of detail was measured by categorizing the utterances as generic, specific, or specific-extended. We found that the two measures were affected differently by all five factors. For instance, number of experienced events positively influenced number of referred events but had no effect on amount of detail provided about the events. We make suggestions for future research and encourage reanalysis of the present data set and reuse of the material.

Use of Repeated Blood Pressure and Cholesterol Measurements to Improve Cardiovascular Disease Risk Prediction: An Individual-Participant-Data Meta-Analysis

PubMed Central

Barrett, Jessica; Pennells, Lisa; Sweeting, Michael; Willeit, Peter; Di Angelantonio, Emanuele; Gudnason, Vilmundur; Nordestgaard, Børge G.; Psaty, Bruce M; Goldbourt, Uri; Best, Lyle G; Assmann, Gerd; Salonen, Jukka T; Nietert, Paul J; Verschuren, W. M. Monique; Brunner, Eric J; Kronmal, Richard A; Salomaa, Veikko; Bakker, Stephan J L; Dagenais, Gilles R; Sato, Shinichi; Jansson, Jan-Håkan; Willeit, Johann; Onat, Altan; de la Cámara, Agustin Gómez; Roussel, Ronan; Völzke, Henry; Dankner, Rachel; Tipping, Robert W; Meade, Tom W; Donfrancesco, Chiara; Kuller, Lewis H; Peters, Annette; Gallacher, John; Kromhout, Daan; Iso, Hiroyasu; Knuiman, Matthew; Casiglia, Edoardo; Kavousi, Maryam; Palmieri, Luigi; Sundström, Johan; Davis, Barry R; Njølstad, Inger; Couper, David; Danesh, John; Thompson, Simon G; Wood, Angela

2017-01-01

Abstract The added value of incorporating information from repeated blood pressure and cholesterol measurements to predict cardiovascular disease (CVD) risk has not been rigorously assessed. We used data on 191,445 adults from the Emerging Risk Factors Collaboration (38 cohorts from 17 countries with data encompassing 1962–2014) with more than 1 million measurements of systolic blood pressure, total cholesterol, and high-density lipoprotein cholesterol. Over a median 12 years of follow-up, 21,170 CVD events occurred. Risk prediction models using cumulative mean values of repeated measurements and summary measures from longitudinal modeling of the repeated measurements were compared with models using measurements from a single time point. Risk discrimination (C-index) and net reclassification were calculated, and changes in C-indices were meta-analyzed across studies. Compared with the single-time-point model, the cumulative means and longitudinal models increased the C-index by 0.0040 (95% confidence interval (CI): 0.0023, 0.0057) and 0.0023 (95% CI: 0.0005, 0.0042), respectively. Reclassification was also improved in both models; compared with the single-time-point model, overall net reclassification improvements were 0.0369 (95% CI: 0.0303, 0.0436) for the cumulative-means model and 0.0177 (95% CI: 0.0110, 0.0243) for the longitudinal model. In conclusion, incorporating repeated measurements of blood pressure and cholesterol into CVD risk prediction models slightly improves risk prediction. PMID:28549073

The effect of intervention on the free-play experience for mothers and their infants with developmental delay and cerebral palsy.

PubMed

Redditi Hanzlik, J

1989-01-01

An intervention study designed to investigate the effects of one hour of maternal and infant behavior was conducted using experimental and control groups of mothers and their infants with cerebral palsy. Ten mother-infant pairs were in each group; infants ranged in age from 8-32 months. Infants of mothers in the control group received one hour of NDT-based occupational therapy. Two-factor repeated measures analysis of variance with repeated measures of the second factor indicated that the nonverbal instruction methods were significantly more successful in modifying maternal and infant behavior than were the verbal instruction methods. Implications of the results for intervention programs and future research were discussed.

The effect of repeated firings on the color change and surface roughness of dental ceramics

PubMed Central

Yılmaz, Kerem; Ozturk, Caner

2014-01-01

PURPOSE The color of the ceramic restorations is affected by various factors such as brand, thickness of the layered the ceramic, condensation techniques, smoothness of surface, number of firings, firing temperature and thickness of dentin. The aim of this study was to evaluate the color change and surface roughness in dental porcelain with different thicknesses during repeated firings. MATERIALS AND METHODS Disc-shaped (N=21) metal-ceramic samples (IPS Classic; Ivoclar Vivadent; Shaar, Liechtenstein) with different thickness were exposed to repeated firings. Color measurement of the samples was made using a colorimeter and profilometer was used to determine surface roughness. ANOVA and Tukey tests with repeated measurements were used for statistical analysis. RESULTS The total thickness of the ceramics which is less than 2 mm significantly have detrimental effect on the surface properties and color of porcelains during firings (P<.05). CONCLUSION Repeated firings have effects on the color change and surface roughness of the dental ceramics and should be avoided. PMID:25177475

Factors influencing repeated teenage pregnancy: a review and meta-analysis.

PubMed

Maravilla, Joemer C; Betts, Kim S; Couto E Cruz, Camila; Alati, Rosa

2017-11-01

Existing evidence of predictors of repeated teenage pregnancy has not been assessed rigorously. This systematic review provides a comprehensive evaluation of protective and risk factors that are associated with repeated teenage pregnancy through a metaanalytical consensus. We used PubMed, EMBASE, CINAHL, ProQuest, PsychINFO, ScienceDirect, Scopus, and Web of Science databases from 1997-2015 and the reference list of other relevant research papers and related reviews. Eligibility criteria included (1) epidemiologic studies that analyzed factors associated with repeated pregnancy or birth among adolescents <20 years of age who were nulliparous or experienced at least 1 pregnancy, and (2) experimental studies with an observational component that was adjusted for the intervention. We performed narrative synthesis of study characteristics, participant characteristics, study results, and quality assessment. We also conducted random-effects and quality-effects metaanalyses with meta-regression to obtain pooled odds ratios of identified factors and to determine sources of between-study heterogeneity. Twenty-six eligible epidemiologic studies, most from the United States (n=24), showed >47 factors with no evidence of publication bias for each metaanalysis. Use of contraception (pooled odds ratio, 0.60; 95% confidence interval, 0.35-1.02), particularly long-acting reversible contraceptives (pooled odds ratio, 0.19; 95% confidence interval, 0.08-0.45), considerably reduced repeated teenage pregnancy risk. Among studies about contraception, the number of follow-up visits (adjusted coefficient, 0.72; P=.102) and country of study (unadjusted coefficient, 2.57; permuted P=.071) explained between-study heterogeneity. Education-related factors, which included higher level of education (pooled odds ratio, 0.74; 95% confidence interval, 0.60-0.91) and school continuation (pooled odds ratio, 0.53; 95% confidence interval, 0.33-0.84), were found to be protective. Conversely, depression (pooled odds ratio, 1.46; 95% confidence interval, 1.14-1.87), history of abortion (pooled odds ratio, 1.66; 95% confidence interval, 1.08-2.54), and relationship factors, such as partner support, increased the repeated teenage pregnancy risk. Contraceptive use, educational factors, depression, and a history of abortion are the highly influential predictors of repeated teenage pregnancy. However, there is a lack of epidemiologic studies in low- and middle-income countries to measure the extent and characteristics of repeated teenage pregnancy across more varied settings. Copyright © 2017 Elsevier Inc. All rights reserved.

Impact of volunteer-related and methodology-related factors on the reproducibility of brachial artery flow-mediated vasodilation: analysis of 672 individual repeated measurements.

PubMed

van Mil, Anke C C M; Greyling, Arno; Zock, Peter L; Geleijnse, Johanna M; Hopman, Maria T; Mensink, Ronald P; Reesink, Koen D; Green, Daniel J; Ghiadoni, Lorenzo; Thijssen, Dick H

2016-09-01

Brachial artery flow-mediated dilation (FMD) is a popular technique to examine endothelial function in humans. Identifying volunteer and methodological factors related to variation in FMD is important to improve measurement accuracy and applicability. Volunteer-related and methodology-related parameters were collected in 672 volunteers from eight affiliated centres worldwide who underwent repeated measures of FMD. All centres adopted contemporary expert-consensus guidelines for FMD assessment. After calculating the coefficient of variation (%) of the FMD for each individual, we constructed quartiles (n = 168 per quartile). Based on two regression models (volunteer-related factors and methodology-related factors), statistically significant components of these two models were added to a final regression model (calculated as β-coefficient and R). This allowed us to identify factors that independently contributed to the variation in FMD%. Median coefficient of variation was 17.5%, with healthy volunteers demonstrating a coefficient of variation 9.3%. Regression models revealed age (β = 0.248, P < 0.001), hypertension (β = 0.104, P < 0.001), dyslipidemia (β = 0.331, P < 0.001), time between measurements (β = 0.318, P < 0.001), lab experience (β = -0.133, P < 0.001) and baseline FMD% (β = 0.082, P < 0.05) as contributors to the coefficient of variation. After including all significant factors in the final model, we found that time between measurements, hypertension, baseline FMD% and lab experience with FMD independently predicted brachial artery variability (total R = 0.202). Although FMD% showed good reproducibility, larger variation was observed in conditions with longer time between measurements, hypertension, less experience and lower baseline FMD%. Accounting for these factors may improve FMD% variability.

Young adult waterpipe smokers: Smoking behaviors and associated subjective and physiological effects.

PubMed

Shishani, Kawkab; Howell, Donelle; McPherson, Sterling; Roll, John

2014-06-01

The purpose of this pilot study was to investigate smoking behaviors and subjective and physiological effects of nicotine on young adult occasional waterpipe smokers. This study utilized a repeated-measures design that included one repeated factor for condition (nicotine and non-nicotine). For each participant, the sequencing of the repeated factor was assigned using random allocation. The two nicotine conditions were nicotine (0.75 g) and non-nicotine (0 g placebo) tobacco. Over the course of two weeks, twenty-two participants completed subjective (Acute Subjective Effects of Nicotine) and physiological (blood pressure, heart rate, and CO level) measures. Additional measures (QSU and MNWS-R) were used to assess for withdrawal symptoms. The participants (n=22) were young adults (23 ± 3.1years); 71% smoked waterpipe once a month in the past year and 29% smoked waterpipe 1-2 times per week. In addition, 60% reported sharing their waterpipe with friends while smoking. None of the participants reported using any other forms of tobacco products. Under the nicotine condition, participants tended to smoke longer (i.e. smoking duration, p=0.004), take more puffs (p=0.03), take shorter puffs (p=0.03), and inhale less volume with each puff (p=0.02). The repeated measures analysis of the factor headrush revealed an effect of the nicotine condition (F=9.69, p<0.001, partial η(2)=0.31) and time (F=8.17, p=0.02, partial η(2)=0.30). Heart rate increased significantly across the nicotine condition (F=7.92, p=0.01, partial η(2)=0.31) and over time (F=12.64, p=0.01, partial η(2)=0.41). This study demonstrates how differences between nicotine and non-nicotine waterpipe smoking are associated with changes in smoking behaviors, experiencing a headrush and an increase in heart rate. Copyright © 2014 Elsevier Ltd. All rights reserved.

A method to measure the ozone penetration factor in residences under infiltration conditions: application in a multifamily apartment unit.

PubMed

Zhao, H; Stephens, B

2016-08-01

Recent experiments have demonstrated that outdoor ozone reacts with materials inside residential building enclosures, potentially reducing indoor exposures to ozone or altering ozone reaction byproducts. However, test methods to measure ozone penetration factors in residences (P) remain limited. We developed a method to measure ozone penetration factors in residences under infiltration conditions and applied it in an unoccupied apartment unit. Twenty-four repeated measurements were made, and results were explored to (i) evaluate the accuracy and repeatability of the new procedure using multiple solution methods, (ii) compare results from 'interference-free' and conventional UV absorbance ozone monitors, and (iii) compare results against those from a previously published test method requiring artificial depressurization. The mean (±s.d.) estimate of P was 0.54 ± 0.10 across a wide range of conditions using the new method with an interference-free monitor; the conventional monitor was unable to yield meaningful results due to relatively high limits of detection. Estimates of P were not clearly influenced by any indoor or outdoor environmental conditions or changes in indoor decay rate constants. This work represents the first known measurements of ozone penetration factors in a residential building operating under natural infiltration conditions and provides a new method for widespread application in buildings. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Self-Control and Impulsivity in Children: Multiple Behavioral Measures

ERIC Educational Resources Information Center

Forzano, L. B.; Michels, Jennifer L.; Carapella, R. K.; Conway, Patrick; Chelonis, J. J.

2011-01-01

The present experiment investigated the relationship between laboratory measures of self-control and delay of gratification in children and explored several other factors that may influence self-control. In the self-control paradigm, 30 four-year-old children repeatedly chose between three reinforcers received after a delay and one reinforcer…

Flavor of fresh blueberry juice and the comparison to amount of sugars, acids, anthocyanidins, and physicochemical measurements

USDA-ARS?s Scientific Manuscript database

Six cultivars of southern highbush (SHB) and rabbiteye (RE) blueberry samples were harvested twice. Each treatment combination was pressed two times for repeated measures. Fresh juice was characterized for eighteen flavor/taste/feeling factor attributes by a descriptive flavor panel. Each sample ...

Factors Associated with Aggressive Behavior among Nursing Home Residents with Dementia

ERIC Educational Resources Information Center

Whall, Ann L.; Colling, Kathleen B.; Kolanowski, Ann; Kim, HyoJeong; Hong, Gwi-Ryung Son; DeCicco, Barry; Ronis, David L.; Richards, Kathy C.; Algase, Donna; Beck, Cornelia

2008-01-01

Purpose: In an attempt to more thoroughly describe aggressive behavior in nursing home residents with dementia, we examined background and proximal factors as guided by the Need-Driven Dementia-Compromised Behavior model. Design and Methods: We used a multivariate cross-sectional survey with repeated measures; participants resided in nine randomly…

Spa Goers' Repeated Visits for Health and Wellness and the Influential Factors: An Exploratory Study of the UK Spa Goers.

PubMed

Choi, Myungsuk; Poade, Donna; Sohn, Minsung; Choi, Mankyu

2016-01-01

Dissemination of spa services across the globe and its market saturation drive demand for differentiated communication methods. This study aims to explore the influential factors on spa goers' repeated visits and their practical applications in the health and wellness spa industry. The identified factors were used as the measurement variables to examine the relation with spa goers' repeated visits. The proposed concept was tested by a mixed method combining a self-administered questionnaire and semistructured interview with 54 survey participants and 6 interviewees. It was meaningful to use a sample of the UK spa goers from the southwest region since global spa trends stem from the EU spas, and the United Kingdom is one of the market leaders. The data were analyzed using frequency, percentage, multiple logistic regression analysis, and coding process. The survey findings demonstrated that the most significant influential factor on the repeated spa visits is a memorable experience of which showed 13.7 times higher probability than the reference up-to-date facility. The details of memorable experiences were discovered throughout the interviews that include the rediscovery of self, feeling of connectedness, recharge for positive emotions, self-reward through escapism, and experience of noncommercialized local products and attractions. Therefore, using experiential marketing methods can be effective spa service marketing.

Class Enumeration and Parameter Recovery of Growth Mixture Modeling and Second-Order Growth Mixture Modeling in the Presence of Measurement Noninvariance between Latent Classes

PubMed Central

Kim, Eun Sook; Wang, Yan

2017-01-01

Population heterogeneity in growth trajectories can be detected with growth mixture modeling (GMM). It is common that researchers compute composite scores of repeated measures and use them as multiple indicators of growth factors (baseline performance and growth) assuming measurement invariance between latent classes. Considering that the assumption of measurement invariance does not always hold, we investigate the impact of measurement noninvariance on class enumeration and parameter recovery in GMM through a Monte Carlo simulation study (Study 1). In Study 2, we examine the class enumeration and parameter recovery of the second-order growth mixture modeling (SOGMM) that incorporates measurement models at the first order level. Thus, SOGMM estimates growth trajectory parameters with reliable sources of variance, that is, common factor variance of repeated measures and allows heterogeneity in measurement parameters between latent classes. The class enumeration rates are examined with information criteria such as AIC, BIC, sample-size adjusted BIC, and hierarchical BIC under various simulation conditions. The results of Study 1 showed that the parameter estimates of baseline performance and growth factor means were biased to the degree of measurement noninvariance even when the correct number of latent classes was extracted. In Study 2, the class enumeration accuracy of SOGMM depended on information criteria, class separation, and sample size. The estimates of baseline performance and growth factor mean differences between classes were generally unbiased but the size of measurement noninvariance was underestimated. Overall, SOGMM is advantageous in that it yields unbiased estimates of growth trajectory parameters and more accurate class enumeration compared to GMM by incorporating measurement models. PMID:28928691

Predictive value of long-term changes of growth differentiation factor-15 over a 27-year-period for heart failure and death due to coronary heart disease.

PubMed

Fluschnik, Nina; Ojeda, Francisco; Zeller, Tanja; Jørgensen, Torben; Kuulasmaa, Kari; Becher, Peter Moritz; Sinning, Christoph; Blankenberg, Stefan; Westermann, Dirk

2018-01-01

Growth differentiation factor-15 (GDF-15), Cystatin C and C-reactive protein (CRP) have been discussed as biomarkers for prediction of cardiac diseases. The aim of this study was to investigate the predictive value of single and repeated measurements of GDF-15 compared to Cystatin C and CRP for incidence of heart failure (HF) and death due to coronary heart disease (CHD) in the general population. Levels of GDF-15, CRP and Cystatin C were determined in three repeated measurements collected 5 years apart in the DAN-MONICA (Danish-Multinational MONitoring of trends and determinants in Cardiovascular disease) cohort (participants at baseline n = 3785). Cox regression models adjusted for cardiovascular risk factors revealed significantly increased hazard ratios (HR) for GDF-15 for incident HF 1.36 (HR per interquartile range (IQR) increase, 95% confidence interval (CI): 1.16; 1.59) and for death from CHD 1.51 (HR per IQR increase, 95% CI: 1.31, 1.75) (both with p<0.001). Joint modeling of time-to-event and longitudinal GDF-15 over a median 27-year follow-up period showed that the marker evolution was positively associated with death of CHD (HR per IQR increase 3.02 95% CI: (2.26, 4.04), p < 0.001) and HF (HR per IQR increase 2.12 95% CI: (1.54, 2.92), p<0.001). However using Cox models with follow-up time starting at the time of the third examination, serial measurement of GDF-15, modeled as changes between the measurements, did not improve prediction over that of the most recent measurement. GDF-15 is a promising biomarker for prediction of HF and death due to CHD in the general population, which may provide prognostic information to already established clinical biomarkers. Repeated measurements of GDF-15 displayed only a slight improvement in the prediction of these endpoints compared to a single measurement.

Short-Term Repeatability of Noninvasive Aortic Pulse Wave Velocity Assessment: Comparison Between Methods and Devices.

PubMed

Grillo, Andrea; Parati, Gianfranco; Rovina, Matteo; Moretti, Francesco; Salvi, Lucia; Gao, Lan; Baldi, Corrado; Sorropago, Giovanni; Faini, Andrea; Millasseau, Sandrine C; Scalise, Filippo; Carretta, Renzo; Salvi, Paolo

2017-12-08

Aortic pulse wave velocity (PWV) is an indirect index of arterial stiffness and an independent cardiovascular risk factor. Consistency of PWV assessment over time is thus an essential feature for its clinical application. However, studies providing a comparative estimate of the reproducibility of PWV across different noninvasive devices are lacking, especially in the elderly and in individuals at high cardiovascular risk. Aimed at filling this gap, short-term repeatability of PWV, estimated with 6 different devices (Complior Analyse, PulsePen-ETT, PulsePen-ET, SphygmoCor Px/Vx, BPLab, and Mobil-O-Graph), was evaluated in 102 high cardiovascular risk patients hospitalized for suspected coronary artery disease (72 males, 65 ± 13 years). PWV was measured in a single session twice, at 15-minute interval, and its reproducibility was assessed though coefficient of variation (CV), coefficient of repeatability, and intraclass correlation coefficient. The CV of PWV, measured with any of these devices, was <10%. Repeatability was higher with cuff-based methods (BPLab: CV = 5.5% and Mobil-O-Graph: CV = 3.4%) than with devices measuring carotid-femoral PWV (Complior: CV = 8.2%; PulsePen-TT: CV = 8.0%; PulsePen-ETT: CV = 5.8%; and SphygmoCor: CV = 9.5%). In the latter group, PWV repeatability was lower in subjects with higher carotid-femoral PWV. The differences in PWV between repeated measurements, except for the Mobil-O-Graph, did not depend on short-term variations of mean blood pressure or heart rate. Our study shows that the short-term repeatability of PWV measures is good but not homogenous across different devices and at different PWV values. These findings, obtained in patients at high cardiovascular risk, may be relevant when evaluating the prognostic importance of PWV. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Effect of repeated earthquake on inelastic moment resisting concrete frame

NASA Astrophysics Data System (ADS)

Tahara, R. M. K.; Majid, T. A.; Zaini, S. S.; Faisal, A.

2017-10-01

This paper investigates the response of inelastic moment resisting concrete building under repeated earthquakes. 2D models consist of 3-storey, 6-storey and 9-storey representing low to medium rise building frame were designed using seismic load and ductility class medium (DCM) according to the requirements set by Euro Code 8. Behaviour factor and stiffness degradation were also taken into consideration. Seven sets of real repeated earthquakes as opposed to artificial earthquakes data were used. The response of the frame was measured in terms of the inter-storey drift and maximum displacement. By adopting repeated earthquake, the recorded mean IDR increased in the range of 3% - 21%. Similarly, in the case of maximum displacement, the values also increased from 20 mm to 40 mm. The findings concluded that the effect of using repeated earthquake in seismic analysis considerably influenced the inter-storey drift and the maximum displacement.

The effects of a multi-axis balance board intervention program in an elderly population.

PubMed

Dougherty, John; Kancel, Anne; Ramar, Cassandra; Meacham, Crystal; Derrington, Stephen

2011-01-01

Balance is a major issue facing the geriatric population. Nine participants from a local community center for seniors completed a five-week study to assess improvement in balance. Measures of balance, performance times, and scores on the Berg Balance Scale (BBS) and the Wii Fit Age (WFA) were recorded before and after the entire intervention. An analysis of variance (ANOVA) with repeated measures was used to assess change in BBS and WFA scores. An analysis of covariance with repeated measures was used to asses the impact of possible contributing factors of age, gender, BMI and total balance board training time over the five-week period. The analysis indicated that use of the Indo Balance Board three times a week for ten minutes can significantly improve balance and potentially decrease the risk of falls, as measured by the BBS. Age was the only factor that significantly influenced balance (p = .006). These improvements are postulated to be due to an increase in subjects' core and lower extremity muscle strength and improved proprioception; a result of balance board usage.

Factors influencing individual variation in perceptual directional microphone benefit.

PubMed

Keidser, Gitte; Dillon, Harvey; Convery, Elizabeth; Mejia, Jorge

2013-01-01

Large variations in perceptual directional microphone benefit, which far exceed the variation expected from physical performance measures of directional microphones, have been reported in the literature. The cause for the individual variation has not been systematically investigated. To determine the factors that are responsible for the individual variation in reported perceptual directional benefit. A correlational study. Physical performance measures of the directional microphones obtained after they had been fitted to individuals, cognitive abilities of individuals, and measurement errors were related to perceptual directional benefit scores. Fifty-nine hearing-impaired adults with varied degrees of hearing loss participated in the study. All participants were bilaterally fitted with a Motion behind-the-ear device (500 M, 501 SX, or 501 P) from Siemens according to the National Acoustic Laboratories' non-linear prescription, version two (NAL-NL2). Using the Bamford-Kowal-Bench (BKB) sentences, the perceptual directional benefit was obtained as the difference in speech reception threshold measured in babble noise (SRTn) with the devices in directional (fixed hypercardioid) and in omnidirectional mode. The SRTn measurements were repeated three times with each microphone mode. Physical performance measures of the directional microphone included the angle of the microphone ports to loudspeaker axis, the frequency range dominated by amplified sound, the in situ signal-to-noise ratio (SNR), and the in situ three-dimensional, articulation-index weighted directivity index (3D AI-DI). The cognitive tests included auditory selective attention, speed of processing, and working memory. Intraparticipant variation on the repeated SRTn's and the interparticipant variation on the average SRTn were used to determine the effect of measurement error. A multiple regression analysis was used to determine the effect of other factors. Measurement errors explained 52% of the variation in perceptual directional microphone benefit (95% confidence interval [CI]: 34-78%), while another 37% of variation was explained primarily by the physical performance of the directional microphones after they were fitted to individuals. The most contributing factor was the in situ 3D AI-DI measured across the low frequencies. Repeated SRTn measurements are needed to obtain a reliable indication of the perceptual directional benefit in an individual. Further, to obtain optimum benefit from directional microphones, the effectiveness of the microphones should be maximized across the low frequencies. American Academy of Audiology.

A Comparison of Low Performing Students' Achievements in Factoring Cubic Polynomials Using Three Different Strategies

ERIC Educational Resources Information Center

Ogbonnaya, Ugorji I.; Mogari, David L.; Machisi, Eric

2013-01-01

In this study, repeated measures design was employed to compare low performing students' achievements in factoring cubic polynomials using three strategies. Twenty-five low-performing Grade 12 students from a secondary school in Limpopo province took part in the study. Data was collected using achievement test and was analysed using repeated…

TU-F-CAMPUS-T-04: Variations in Nominally Identical Small Fields From Photon Jaw Reproducibility and Associated Effects On Small Field Dosimetric Parameters

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

Muir, B R; McEwen, M R

2015-06-15

Purpose: To investigate uncertainties in small field output factors and detector specific correction factors from variations in field size for nominally identical fields using measurements and Monte Carlo simulations. Methods: Repeated measurements of small field output factors are made with the Exradin W1 (plastic scintillation detector) and the PTW microDiamond (synthetic diamond detector) in beams from the Elekta Precise linear accelerator. We investigate corrections for a 0.6x0.6 cm{sup 2} nominal field size shaped with secondary photon jaws at 100 cm source to surface distance (SSD). Measurements of small field profiles are made in a water phantom at 10 cm depthmore » using both detectors and are subsequently used for accurate detector positioning. Supplementary Monte Carlo simulations with EGSnrc are used to calculate the absorbed dose to the detector and absorbed dose to water under the same conditions when varying field size. The jaws in the BEAMnrc model of the accelerator are varied by a reasonable amount to investigate the same situation without the influence of measurements uncertainties (such as detector positioning or variation in beam output). Results: For both detectors, small field output factor measurements differ by up to 11 % when repeated measurements are made in nominally identical 0.6x0.6 cm{sup 2} fields. Variations in the FWHM of measured profiles are consistent with field size variations reported by the accelerator. Monte Carlo simulations of the dose to detector vary by up to 16 % under worst case variations in field size. These variations are also present in calculations of absorbed dose to water. However, calculated detector specific correction factors are within 1 % when varying field size because of cancellation of effects. Conclusion: Clinical physicists should be aware of potentially significant uncertainties in measured output factors required for dosimetry of small fields due to field size variations for nominally identical fields.« less

Scoping review of risk factors of and interventions for adolescent repeat pregnancies: A public health perspective.

PubMed

Govender, Desiree; Naidoo, Saloshni; Taylor, Myra

2018-06-19

Adolescent repeat pregnancy is of importance in public health because the birth of a second child to an adolescent mother compounds the adverse medical, educational, socioeconomic and parenting outcomes. Repeat pregnancy in adolescence is not only an international phenomenon but also a local concern as it also occurs in South Africa. The prevalence of adolescent repeat pregnancy in Durban, KwaZulu-Natal, was reported as 17.6% in 2013. This review aimed to gather relevant information from national and international sources to inform practice and to provide an understanding of what is known about the risk factors of and the interventions for adolescent repeat pregnancy. A scoping review was undertaken using the Arksey and O'Malley framework. An electronic search was conducted using PubMed, Medline, Science Direct, Ebscohost, Sage and Wiley Online and Google Scholar. The search identified 3032 citations. After a review of the full text articles, 26 articles met the inclusion criteria. Risk factors pertaining to adolescent repeat pregnancy are categorised according to individual factors, partner relationship factors, family factors, peer factors, and social and community factors. Interventions to reduce adolescent repeat pregnancy have been largely influenced by the ecological framework. Across studies, adolescent mothers who received medical, psychosocial, educational, and family planning support experienced lower rates of repeat pregnancy. A single 'one-size-fits-all' intervention for adolescent repeat pregnancy prevention is unlikely as different strategies were employed by the intervention programmes in this scoping review.

Telomere length and telomere repeating factors: Cellular markers for post-traumatic stress disorder-like model.

PubMed

Dong, Yuanjun; Zhang, Guiqing; Yuan, Xiuyu; Zhang, Yueqi; Hu, Min

2016-05-01

The aim of the present study was to explore the telomere length of peripheral blood leukocytes from a rat model of post-traumatic stress disorder (PTSD), as well as the expression level of telomere-binding protein in the hippocampal CA1 region. The PTSD model was established with 42 adult male Wistar rats. The relative telomere length of the leukocytes was measured by real-time fluorescence quantitative polymerase chain reaction, and the expression levels of telomere repeating factor 1 (TRF1) and telomere repeating factor 2 (TRF2) in the hippocampal CA1 region of the PTSD rat model were determined by immunofluorescence technology. The covariance analysis of repeated measurements by the mixed model approach was used for the telomere length analysis. The comparison of averaged data among groups was performed using least significant difference and analysis of variance. The Student's t test or the Mann-Whitney U test was used for intragroup comparison. The association study among groups was conducted using the Spearman test. The shortening speed of telomere length significantly accelerated in rats after Single Prolonged Stress (SPS) stimulation (P<0.05). The expression levels of TRF1 and TRF2 increased with the progress of PTSD, and the expression peak was shown in day 14, which was significantly different from the control group (P<0.05). The shortening speed of the telomere length of peripheral blood leukocytes accelerated in PTSD rats, and the expression levels of TRF1 and TRF2 increased in hippocampus, both of which were closely associated with the pathological progress of the PTSD-like model and unfavorable prognosis. Copyright © 2016 Elsevier B.V. All rights reserved.

Chronic exposure to adverse psychosocial work factors and high psychological distress among white-collar workers: A 5-year prospective study.

PubMed

Ndjaboue, Ruth; Brisson, Chantal; Talbot, Denis; Vézina, Michel

2017-03-01

Prospective studies which evaluated whether the effects of chronic exposure to psychosocial work factors on mental health persisted over time are scarce. For the first time, this study evaluated: 1) the effect of chronic exposure to effort-reward imbalance over 5years on the prevalence of high psychological distress among men and women, and 2) the persistence of this effect over time. Overall, 1747 white-collar workers from three public organizations participated in a prospective study. Psychological distress and effort-reward imbalance were measured using validated questionnaires at baseline, and at 3- and 5-year follow-ups. Prevalence ratios (PRs) of high psychological distress were estimated using log-binomial regression according to baseline and repeated exposure. Compared to unexposed workers, those with repeated exposure to effort-reward imbalance had a higher prevalence of high psychological distress. Workers exposed only at some time-points also had a higher prevalence. The deleterious effect of repeated exposure observed at the 3-year follow-up persisted at the 5-year follow-up among women (PR=2.48 95% confidence interval (CI) 1.97-3.11) and men (PR=1.91 95% CI 1.20-3.04). These effects were greater than those found using a single baseline measurement. The current study supported a deleterious effect of repeated exposure to effort-reward imbalance on psychological distress, and a lack of adaptation to these effects over time among men and women. Since psychological distress may later lead to severe mental problems, current results highlight the need to consider exposure to these adverse work factors in primary and secondary preventions aimed at reducing mental health problems at work. Copyright © 2017 Elsevier Inc. All rights reserved.

General radiographic attributes of optically stimulated luminescence dosimeters: A basic insight

NASA Astrophysics Data System (ADS)

Musa, Y.; Hashim, S.; Ghoshal, S. K.; Bradley, D. A.; Ahmad, N. E.; Karim, M. K. A.; Hashim, A.; Kadir, A. B. A.

2018-06-01

We report the ubiquitous radiographic characteristics of optically stimulated luminescence dosimeters (OSLD) so called nanoDot OSLDs (Landauer Inc., Glendwood, IL). The X-ray irradiations were performed in free air ambiance to inspect the repeatability, the reproducibility, the signal depletion, the element correction factors (ECFs), the dose response and the energy dependence. Repeatability of multiple readouts after single irradiation to 10 mGy revealed a coefficient of variation below 3%, while the reproducibility in repeated irradiation-readout-annealing cycles was above 2%. The OSL signal depletion for three nanoDots with simultaneous irradiation to 20 mGy and sequential readouts of 25 times displayed a consistent signal reduction ≈0.5% per readout with R2 values over 0.98. ECFs for individual OSLDs were varied from 0.97 to 1.03. In the entire dose range under 80 kV, a good linearity with an R2 exceeding 0.99 was achieved. Besides, the percentage difference between OSLD and ion-chamber dose was less than 5%, which was superior to TLD. The X-ray photon irradiated energy response factors (between 0.76 and 1.12) in the range of 40-150 kV (26.1-61.2 keV) exhibited significant energy dependence. Indeed, the nanoDot OSLDs disclosed good repeatability, reproducibility and linearity. The OSLDs measured doses were closer to ion-chamber doses than that of TLD. It can be further improved up to ≈3% by applying the individual dosimeter ECF. On top, the energy dependent uncertainties can be minimized using the energy correction factors. It is established that the studied nanoDot OSLDs are prospective for measuring entrance dose in general radiographic practices.

Evaluation of a device for standardized measurements of reading performance in a prepresbyopic population.

PubMed

Arad, Tschingis; Baumeister, Martin; Bühren, Jens; Kohnen, Thomas

2017-04-20

Automated measurements of reading performance are required for clinical trials involving presbyopia-correcting surgery options. Repeatability of a testing device for reading (Salzburg Reading Desk) was evaluated in a prepresbyopic population. Subjective reading performance of 50 subjects divided into 2 age groups (23-30 years and 38-49 years) with distance-corrected eyes was investigated with different log-scaled reading charts. At study entry, refractive parameters were measured and distance visual acuity assessed. Two standardized binocular measurements were performed for each subject (32.24 ± 9.87 days apart [mean ± SD]). The repeatability of the tests was estimated using correlation coefficients, Wilcoxon signed-rank test, and Bland-Altman method. The test parameters at both maximum reading rate (MRR) measurements demonstrate a strong relationship of age group 2 subjects (correlation coefficient [r] = 0.74 p = 10-4) and of younger subjects (age group 1: r = 0.69, p = 10-4). Prepresbyopic subjects of age group 2 showed moderate results for near reading distance (r = 0.67, p = 10-4); by contrast, younger subjects had poorer results (r = 0.55, p = 10-3). The Wilcoxon signed-rank test revealed agreement between measurements and Bland-Altman plots showed a wide data spread for MRR and near reading distance in both groups. The device measures repeatedly selected reading performance parameters of near real world conditions, such as MRR, in prepresbyopic populations if several factors are taken into account. The option to choose preferred distance leads to more variance in measuring repeated reading performance. German Clinical Trials Register (DRKS) registration reference number: DRKS00000784.

Repeated electromagnetic induction measurements for mapping soil moisture at the field scale: validation with data from a wireless soil moisture monitoring network

NASA Astrophysics Data System (ADS)

Martini, Edoardo; Werban, Ulrike; Zacharias, Steffen; Pohle, Marco; Dietrich, Peter; Wollschläger, Ute

2017-01-01

Electromagnetic induction (EMI) measurements are widely used for soil mapping, as they allow fast and relatively low-cost surveys of soil apparent electrical conductivity (ECa). Although the use of non-invasive EMI for imaging spatial soil properties is very attractive, the dependence of ECa on several factors challenges any interpretation with respect to individual soil properties or states such as soil moisture (θ). The major aim of this study was to further investigate the potential of repeated EMI measurements to map θ, with particular focus on the temporal variability of the spatial patterns of ECa and θ. To this end, we compared repeated EMI measurements with high-resolution θ data from a wireless soil moisture and soil temperature monitoring network for an extensively managed hillslope area for which soil properties and θ dynamics are known. For the investigated site, (i) ECa showed small temporal variations whereas θ varied from very dry to almost saturation, (ii) temporal changes of the spatial pattern of ECa differed from those of the spatial pattern of θ, and (iii) the ECa-θ relationship varied with time. Results suggest that (i) depending upon site characteristics, stable soil properties can be the major control of ECa measured with EMI, and (ii) for soils with low clay content, the influence of θ on ECa may be confounded by changes of the electrical conductivity of the soil solution. Further, this study discusses the complex interplay between factors controlling ECa and θ, and the use of EMI-based ECa data with respect to hydrological applications.

Repeated Nrf2 stimulation using sulforaphane protects fibroblasts from ionizing radiation.

PubMed

Mathew, Sherin T; Bergström, Petra; Hammarsten, Ola

2014-05-01

Most of the cytotoxicity induced by ionizing radiation is mediated by radical-induced DNA double-strand breaks. Cellular protection from free radicals can be stimulated several fold by sulforaphane-mediated activation of the transcription factor Nrf2 that regulates more than 50 genes involved in the detoxification of reactive substances and radicals. Here, we report that repeated sulforaphane treatment increases radioresistance in primary human skin fibroblasts. Cells were either treated with sulforaphane for four hours once or with four-hour treatments repeatedly for three consecutive days prior to radiation exposure. Fibroblasts exposed to repeated-sulforaphane treatment showed a more pronounced dose-dependent induction of Nrf2-regulated mRNA and reduced amount of radiation-induced free radicals compared with cells treated once with sulforaphane. In addition, radiation- induced DNA double-strand breaks measured by gamma-H2AX foci were attenuated following repeated sulforaphane treatment. As a result, cellular protection from ionizing radiation measured by the 5-ethynyl-2'-deoxyuridine (EdU) assay was increased, specifically in cells exposed to repeated sulforaphane treatment. Sulforaphane treatment was unable to protect Nrf2 knockout mouse embryonic fibroblasts, indicating that the sulforaphane-induced radioprotection was Nrf2-dependent. Moreover, radioprotection by repeated sulforaphane treatment was dose-dependent with an optimal effect at 10 uM, whereas both lower and higher concentrations resulted in lower levels of radioprotection. Our data indicate that the Nrf2 system can be trained to provide further protection from radical damage. Copyright © 2014 Elsevier Inc. All rights reserved.

Repeated Nrf2 stimulation using sulforaphane protects fibroblasts from ionizing radiation

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

Mathew, Sherin T.; Bergström, Petra; Hammarsten, Ola, E-mail: ola.hammarsten@clinchem.gu.se

2014-05-01

Most of the cytotoxicity induced by ionizing radiation is mediated by radical-induced DNA double-strand breaks. Cellular protection from free radicals can be stimulated several fold by sulforaphane-mediated activation of the transcription factor Nrf2 that regulates more than 50 genes involved in the detoxification of reactive substances and radicals. Here, we report that repeated sulforaphane treatment increases radioresistance in primary human skin fibroblasts. Cells were either treated with sulforaphane for four hours once or with four-hour treatments repeatedly for three consecutive days prior to radiation exposure. Fibroblasts exposed to repeated-sulforaphane treatment showed a more pronounced dose-dependent induction of Nrf2-regulated mRNA andmore » reduced amount of radiation-induced free radicals compared with cells treated once with sulforaphane. In addition, radiation- induced DNA double-strand breaks measured by gamma-H2AX foci were attenuated following repeated sulforaphane treatment. As a result, cellular protection from ionizing radiation measured by the 5-ethynyl-2′-deoxyuridine (EdU) assay was increased, specifically in cells exposed to repeated sulforaphane treatment. Sulforaphane treatment was unable to protect Nrf2 knockout mouse embryonic fibroblasts, indicating that the sulforaphane-induced radioprotection was Nrf2-dependent. Moreover, radioprotection by repeated sulforaphane treatment was dose-dependent with an optimal effect at 10 uM, whereas both lower and higher concentrations resulted in lower levels of radioprotection. Our data indicate that the Nrf2 system can be trained to provide further protection from radical damage. - Highlights: • Repeated treatment with sulforaphane protects fibroblasts from ionizing radiation • Repeated sulforaphane treatment attenuates radiation induced ROS and DNA damage • Sulforaphane mediated protection is Nrf2 dependent.« less

Proactive behavior, but not inhibitory control, predicts repeated innovation by spotted hyenas tested with a multi-access box.

PubMed

Johnson-Ulrich, Lily; Johnson-Ulrich, Zoe; Holekamp, Kay

2018-05-01

Innovation is widely linked to cognitive ability, brain size, and adaptation to novel conditions. However, successful innovation appears to be influenced by both cognitive factors, such as inhibitory control, and non-cognitive behavioral traits. We used a multi-access box (MAB) paradigm to measure repeated innovation, the number of unique innovations learned across trials, by 10 captive spotted hyenas (Crocuta crocuta). Spotted hyenas are highly innovative in captivity and also display striking variation in behavioral traits, making them good model organisms for examining the relationship between innovation and other behavioral traits. We measured persistence, motor diversity, motivation, activity, efficiency, inhibitory control, and neophobia demonstrated by hyenas while interacting with the MAB. We also independently assessed inhibitory control with a detour cylinder task. Most hyenas were able to solve the MAB at least once, but only four hyenas satisfied learning criteria for all four possible solutions. Interestingly, neither measure of inhibitory control predicted repeated innovation. Instead, repeated innovation was predicted by a proactive syndrome of behavioral traits that included high persistence, high motor diversity, high activity and low neophobia. Our results suggest that this proactive behavioral syndrome may be more important than inhibitory control for successful innovation with the MAB by members of this species.

Barrier function and natural moisturizing factor levels after cumulative exposure to a fruit-derived organic acid and a detergent: different outcomes in atopic and healthy skin and relevance for occupational contact dermatitis in the food industry.

PubMed

Angelova-Fischer, Irena; Hoek, Anne-Karin; Dapic, Irena; Jakasa, Ivone; Kezic, Sanja; Fischer, Tobias W; Zillikens, Detlef

2015-12-01

Fruit-derived organic compounds and detergents are relevant exposure factors for occupational contact dermatitis in the food industry. Although individuals with atopic dermatitis (AD) are at risk for development of occupational contact dermatitis, there have been no controlled studies on the effects of repeated exposure to multiple irritants, relevant for the food industry, in atopic skin. The aim of the study was to investigate the outcomes of repeated exposure to a fruit-derived organic acid and a detergent in AD compared to healthy volunteers. The volunteers were exposed to 2.0% acetic acid (AcA) and/or 0.5% sodium lauryl sulfate (SLS) in controlled tandem repeated irritation test. The outcomes were assessed by measurements of erythema, transepidermal water loss (TEWL) and natural moisturizing factor (NMF) levels. In the AD volunteers, repeated AcA exposure led to barrier disruption and significant TEWL increase; no significant differences after the same exposure in the healthy controls were found. Repeated exposure to SLS and the irritant tandems enhanced the reactions and resulted in a significantly higher increase in TEWL in the AD compared to the control group. Cumulative irritant exposure reduced the NMF levels in both groups. Differences in the severity of irritant-induced barrier impairment in atopic individuals contribute to the risk for occupational contact dermatitis in result of multiple exposures to food-derived irritants and detergents. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Development and validation of a 6-item working alliance questionnaire for repeated administrations during psychotherapy.

PubMed

Falkenström, Fredrik; Hatcher, Robert L; Skjulsvik, Tommy; Larsson, Mattias Holmqvist; Holmqvist, Rolf

2015-03-01

Recently, researchers have started to measure the working alliance repeatedly across sessions of psychotherapy, relating the working alliance to symptom change session by session. Responding to questionnaires after each session can become tedious, leading to careless responses and/or increasing levels of missing data. Therefore, assessment with the briefest possible instrument is desirable. Because previous research on the Working Alliance Inventory has found the separation of the Goal and Task factors problematic, the present study examined the psychometric properties of a 2-factor, 6-item working alliance measure, adapted from the Working Alliance Inventory, in 3 patient samples (ns = 1,095, 235, and 234). Results showed that a bifactor model fit the data well across the 3 samples, and the factor structure was stable across 10 sessions of primary care counseling/psychotherapy. Although the bifactor model with 1 general and 2 specific factors outperformed the 1-factor model in terms of model fit, dimensionality analyses based on the bifactor model results indicated that in practice the instrument is best treated as unidimensional. Results support the use of composite scores of all 6 items. The instrument was validated by replicating previous findings of session-by-session prediction of symptom reduction using the Autoregressive Latent Trajectory model. The 6-item working alliance scale, called the Session Alliance Inventory, is a promising alternative for researchers in search for a brief alliance measure to administer after every session. 2015 APA, all rights reserved

Measurements of propeller noise in a light turboprop airplane

NASA Technical Reports Server (NTRS)

Wilby, J. F.; Wilby, E. G.

1987-01-01

In-flight acoustic measurements have been made on the exterior and interior of a twin-engined turboprop airplane under controlled conditions to study data repeatability. It is found that the variability of the harmonic sound pressure levels in the cabin is greater than that for the exterior sound pressure levels, typical values for the standard deviation being +2.0 dB and -4.2 dB for the interior, versus +1.4 dB and -2.3 dB for the exterior. When insertion losses are determined for acoustic treatments in the cabin, the standard deviations of the data are typically + or - 6.5 dB. It is concluded that additional factors, such as accurate and repeatable selection of relative phase between propellers, controlled cabin-air-temperatures, installation of baseline acoustic absorption, and measurement of aircraft attitude, should be considered in order to reduce uncertainty in the measured data.

Scale factor measure method without turntable for angular rate gyroscope

NASA Astrophysics Data System (ADS)

Qi, Fangyi; Han, Xuefei; Yao, Yanqing; Xiong, Yuting; Huang, Yuqiong; Wang, Hua

2018-03-01

In this paper, a scale factor test method without turntable is originally designed for the angular rate gyroscope. A test system which consists of test device, data acquisition circuit and data processing software based on Labview platform is designed. Taking advantage of gyroscope's sensitivity of angular rate, a gyroscope with known scale factor, serves as a standard gyroscope. The standard gyroscope is installed on the test device together with a measured gyroscope. By shaking the test device around its edge which is parallel to the input axis of gyroscope, the scale factor of the measured gyroscope can be obtained in real time by the data processing software. This test method is fast. It helps test system miniaturized, easy to carry or move. Measure quarts MEMS gyroscope's scale factor multi-times by this method, the difference is less than 0.2%. Compare with testing by turntable, the scale factor difference is less than 1%. The accuracy and repeatability of the test system seems good.

Is ADHD a Risk Factor for High School Dropout? A Controlled Study.

PubMed

Fried, Ronna; Petty, Carter; Faraone, Stephen V; Hyder, Laran L; Day, Helen; Biederman, Joseph

2016-05-01

This study examined whether ADHD was an independent contributor to grade retention when adjusting for IQ, learning disorders, and social class. Outcome data was from participants in studies at Massachusetts General Hospital (n= 404 ADHD,n= 349 controls) who underwent psychiatric interviews, socioeconomic status measures, and IQ testing. 28% of individuals with ADHD repeated a grade compared with 7% of controls (p< .001). Among participants with ADHD, social class, and IQ were significant predictors of high school dropout or repeated grade. An interaction effect of ADHD and gender was also found with females with ADHD having a higher risk ratio for repeated grade/dropout compared with males with ADHD. Participants with ADHD were significantly more likely to repeat a grade, adjusting for all other variables indicating the critical importance of early identification of ADHD to help mitigate adverse educational outcomes. © The Author(s) 2013.

The impact of nonclinical factors on repeat cesarean section.

PubMed

Stafford, R S

1991-01-02

Nonclinical factors, including the setting in which health care takes place, influence clinical decisions. This research measures the independent effects of organizational and socioeconomic factors on repeat cesarean section use in California. Of 45,425 births to women with previous cesarean sections in 1986, vaginal birth after cesarean section occurred in 10.9%. Sizable nonclinical variations were noted. By hospital ownership, rates ranged from 4.9% (for-profit hospitals) to 29.2% (University of California). Variations also existed by hospital teaching level (nonteaching hospitals, 7.0%, vs formalized teaching hospitals, 23.3%); payment source (private insurance, 8.1%, vs indigent services, 25.2%); and obstetric volume (low-volume hospitals, 5.4%, vs high-volume hospitals, 16.6%). Multiple logistic regression demonstrated that these variables had independent effects after accounting for their overlapping influences and the effects of patient characteristics. The observed variations demonstrate the prominence of nonclinical factors in decision making and question the clinical appropriateness of current practice patterns.

Psychosocial factors at home and at work and levels of salivary cortisol.

PubMed

Eller, Nanna Hurwitz; Netterstrøm, Bo; Hansen, Ase Marie

2006-10-01

Salivary cortisol as a physiological measure of stress has attracted great interest in recent years. A 55 women and 28 men, all healthy volunteers, were included in a study on psychosocial factors at work and at home and salivary cortisol. General linear models, univariate and repeated measures, respectively, were used to evaluate the associations between psychosocial factors and cortisol excretion measured six times during a working day. Age, physical activity, tobacco use and the time of the first saliva sample were used as covariates. In the women, high degrees of time pressure, effort and effort reward imbalance were significantly associated with higher levels of cortisol. In the men, high degrees of effort, effort reward imbalance and overcommitment were significantly associated with higher levels of cortisol. Psychosocial factors are of significance to the level of salivary cortisol. The study emphasises the benefits of taking physiological measurements of stress in epidemiological studies.

[Analysis of variance of repeated data measured by water maze with SPSS].

PubMed

Qiu, Hong; Jin, Guo-qin; Jin, Ru-feng; Zhao, Wei-kang

2007-01-01

To introduce the method of analyzing repeated data measured by water maze with SPSS 11.0, and offer a reference statistical method to clinical and basic medicine researchers who take the design of repeated measures. Using repeated measures and multivariate analysis of variance (ANOVA) process of the general linear model in SPSS and giving comparison among different groups and different measure time pairwise. Firstly, Mauchly's test of sphericity should be used to judge whether there were relations among the repeatedly measured data. If any (P

Controls of repeating earthquakes' location from a- and b- values imaging

NASA Astrophysics Data System (ADS)

Chen, K. H.; Kawamura, M.

2017-12-01

The locations where creeping and locked fault areas abut have commonly found to be delineated by the foci of small repeating earthquakes (REs). REs not only represent the finer structure of high creep-rate location, they also function as fault slip-rate indicators. Knowledge of the expected location of REs therefore, is crucial for fault deformation monitoring and assessment of earthquake potential. However, a precise description of factors determining REs locations is lacking. To explore where earthquakes tend to recur, we statistically investigated repeating earthquake catalogs and background seismicity from different regions including six fault segments in California and Taiwan. We show that the location of repeating earthquakes can be mapped using the spatial distribution of the seismic a- and b-values obtained from the background seismicity. Molchan's error diagram statistically confirmed that repeating earthquakes occur within areas with high a-values (2.8-3.8) and high b-values (0.9-1.1) on both strike-slip and thrust fault segments. However, no significant association held true for fault segments with more complicated geometry or for wider areas with a complex fault network. The productivity of small earthquakes responsible for high a- and b-values may thus be the most important factor controlling the location of repeating earthquakes. We hypothesize that, given that the deformation conditions within a fault zone are suitable for a planar fault plane, the location of repeating earthquakes can be best described by a-value 3 and b-value 1. This feature of a- and b-values may be useful for foresee the location of REs for measuring creep rate at depth. Further investigation of REs-rich areas may allow testing of this hypothesis.

Estimation of non-solid lung nodule volume with low-dose CT protocols: effect of reconstruction algorithm and measurement method

NASA Astrophysics Data System (ADS)

Gavrielides, Marios A.; DeFilippo, Gino; Berman, Benjamin P.; Li, Qin; Petrick, Nicholas; Schultz, Kurt; Siegelman, Jenifer

2017-03-01

Computed tomography is primarily the modality of choice to assess stability of nonsolid pulmonary nodules (sometimes referred to as ground-glass opacity) for three or more years, with change in size being the primary factor to monitor. Since volume extracted from CT is being examined as a quantitative biomarker of lung nodule size, it is important to examine factors affecting the performance of volumetric CT for this task. More specifically, the effect of reconstruction algorithms and measurement method in the context of low-dose CT protocols has been an under-examined area of research. In this phantom study we assessed volumetric CT with two different measurement methods (model-based and segmentation-based) for nodules with radiodensities of both nonsolid (-800HU and -630HU) and solid (-10HU) nodules, sizes of 5mm and 10mm, and two different shapes (spherical and spiculated). Imaging protocols included CTDIvol typical of screening (1.7mGy) and sub-screening (0.6mGy) scans and different types of reconstruction algorithms across three scanners. Results showed that radio-density was the factor contributing most to overall error based on ANOVA. The choice of reconstruction algorithm or measurement method did not affect substantially the accuracy of measurements; however, measurement method affected repeatability with repeatability coefficients ranging from around 3-5% for the model-based estimator to around 20-30% across reconstruction algorithms for the segmentation-based method. The findings of the study can be valuable toward developing standardized protocols and performance claims for nonsolid nodules.

Regional repeatability measures of corneal thickness: Orbscan II and ultrasound.

PubMed

Jonuscheit, Sven; Doughty, Michael J

2007-01-01

To compare repeatability of the measures of corneal thickness obtained by slit-scanning light method (Orbscan II) with those obtained by an ultrasound pachymeter, with special interest in the peripheral region of the cornea. On 24 normal adults, aged 20 to 58 years (average 36 years) with up to -8.5 DS refractive error, three measures of corneal thickness were taken using Orbscan II and then by ultrasound pachymetry (under topical anesthesia with benoxinate 0.4%). The Orbscan central sample zone of 1 mm was selected, or the numerical maps were used to extract single point data along the horizontal corneal meridian to the nasal and temporal sides out to 4.5 mm. Ultrasound readings were taken from the central cornea and at the periphery just inside the limbus (4.5 mm from center) with a 2.4-mm diameter probe. For a central 1-mm diameter zone, the coefficient of variation (CV) for three consecutive corneal thickness measures was 0.81%+/-0.44%, but was marginally higher (p=0.004), if just the central single point data was taken with Orbscan (0.86%+/-0.45%). Similar repeatability was noted for the numerical output across the temporal side along the horizontal meridian out to 2.5 mm from the center, but farther out to 4 mm and on the nasal side the repeatability was slightly less and around 1.0% (p<0.001). Orbscan point readings of thickness could only sometimes be obtained at 4.5 mm temporally (with a poorer CV of 1.32%) and very rarely at 4.5 mm on the nasal side. No absolute differences in Orbscan repeatability were noted when comparing emmetropic with myopic subjects (p>or=0.5). Ultrasound pachymetry readings across the central zone were repeatable to 0.82%+/-0.67%. When measured with the edge of the ultrasound probe just touching the limbus, the repeatability of ultrasound readings was 1.37%+/-1.10% temporally and 1.49%+/-1.02% nasally, but neither was statistically worse that the most peripheral readings for Orbscan (p>or=0.210). However, it was also noted that the absolute values of corneal thickness, even with the application of the 0.92 acoustic factor, were 0.010 mm greater for Orbscan at the center and 0.040 mm in the corneal periphery. Orbscan II provides the clinician with a repeatable noninvasive method of measuring corneal thickness that is not necessarily any better than ultrasound pachymetry, and should not be considered as interchangeable with that for ultrasound.

Oxidative Stress Measures of Lipid and DNA Damage in Human Tears.

PubMed

Haworth, Kristina M; Chandler, Heather L

2017-05-01

We evaluate feasibility and repeatability of measures for lipid peroxidation and DNA oxidation in human tears, as well as relationships between outcome variables, and compared our findings to previously reported methods of evaluation for ocular sun exposure. A total of 50 volunteers were seen for 2 visits 14 ± 2 days apart. Tear samples were collected from the inferior tear meniscus using a glass microcapillary tube. Oxidative stress biomarkers were quantified using enzyme-linked immunosorbent assay (ELISA): lipid peroxidation by measurement of hexanoyl-lysine (HEL) expression; DNA oxidation by measurement of 8-oxo-2'-deoxyguinosone (8OHdG) expression. Descriptive statistics were generated. Repeatability estimates were made using Bland-Altman plots with mean differences and 95% limits of agreement were calculated. Linear regression was conducted to evaluate relationships between measures. Mean (±SD) values for tear HEL and 8OHdG expression were 17368.02 (±9878.42) nmol/L and 66.13 (±19.99) ng/mL, respectively. Repeatability was found to be acceptable for both HEL and 8OHdG expression. Univariate linear regression supported tear 8OHdG expression and spring season of collection to be predictors of higher tear HEL expression; tear HEL expression was confirmed as a predictor of higher tear 8OHdG expression. We demonstrate feasibility and repeatability of estimating previously unreported tear 8OHdG expression. Seasonal temperature variation and other factors may influence tear lipid peroxidation. Support is demonstrated to suggest lipid damage and DNA damage occur concurrently on the human ocular surface.

Repeatability and Accuracy of Exoplanet Eclipse Depths Measured with Post-cryogenic Spitzer

NASA Astrophysics Data System (ADS)

Ingalls, James G.; Krick, J. E.; Carey, S. J.; Stauffer, John R.; Lowrance, Patrick J.; Grillmair, Carl J.; Buzasi, Derek; Deming, Drake; Diamond-Lowe, Hannah; Evans, Thomas M.; Morello, G.; Stevenson, Kevin B.; Wong, Ian; Capak, Peter; Glaccum, William; Laine, Seppo; Surace, Jason; Storrie-Lombardi, Lisa

2016-08-01

We examine the repeatability, reliability, and accuracy of differential exoplanet eclipse depth measurements made using the InfraRed Array Camera (IRAC) on the Spitzer Space Telescope during the post-cryogenic mission. We have re-analyzed an existing 4.5 μm data set, consisting of 10 observations of the XO-3b system during secondary eclipse, using seven different techniques for removing correlated noise. We find that, on average, for a given technique, the eclipse depth estimate is repeatable from epoch to epoch to within 156 parts per million (ppm). Most techniques derive eclipse depths that do not vary by more than a factor 3 of the photon noise limit. All methods but one accurately assess their own errors: for these methods, the individual measurement uncertainties are comparable to the scatter in eclipse depths over the 10 epoch sample. To assess the accuracy of the techniques as well as to clarify the difference between instrumental and other sources of measurement error, we have also analyzed a simulated data set of 10 visits to XO-3b, for which the eclipse depth is known. We find that three of the methods (BLISS mapping, Pixel Level Decorrelation, and Independent Component Analysis) obtain results that are within three times the photon limit of the true eclipse depth. When averaged over the 10 epoch ensemble, 5 out of 7 techniques come within 60 ppm of the true value. Spitzer exoplanet data, if obtained following current best practices and reduced using methods such as those described here, can measure repeatable and accurate single eclipse depths, with close to photon-limited results.

Digital Photoplethysmography for Assessment of Arterial Stiffness: Repeatability and Comparison with Applanation Tonometry

PubMed Central

Östling, Gerd; Nilsson, Peter M.

2015-01-01

Introduction Arterial stiffness is an independent risk factor for cardiovascular morbidity and can be assessed by applanation tonometry by measuring pulse wave velocity (PWV) and augmentation index (AIX) by pressure pulse wave analysis (PWA). As an inexpensive and operator independent alternative, photoelectric plethysmography (PPG) has been introduced with analysis of the digital volume pulse wave (DPA) and its second derivatives of wave reflections. Objective The objective was to investigate the repeatability of arterial stiffness parameters measured by digital pulse wave analysis (DPA) and the associations to applanation tonometry parameters. Methods and Results 112 pregnant and non-pregnant individuals of different ages and genders were examined with SphygmoCor arterial wall tonometry and Meridian DPA finger photoplethysmography. Coefficients of repeatability, Bland-Altman plots, intraclass correlation coefficients and correlations to heart rate (HR) and body height were calculated for DPA variables, and the DPA variables were compared to tonometry variables left ventricular ejection time (LVET), PWV and AIX. No DPA variable showed any systematic measurement error or excellent repeatability, but dicrotic index (DI), dicrotic dilatation index (DDI), cardiac ejection elasticity index (EEI), aging index (AI) and second derivatives of the crude pulse wave curve, b/a and e/a, showed good repeatability. Overall, the correlations to AIX were better than to PWV, with correlations coefficients >0.70 for EEI, AI and b/a. Considering the level of repeatability and the correlations to tonometry, the overall best DPA parameters were EEI, AI and b/a. The two pansystolic time parameters, ejection time compensated (ETc) by DPA and LVET by tonometry, showed a significant but weak correlation. Conclusion For estimation of the LV function, ETc, EEI and b/a are suitable, for large artery stiffness EEI, and for small arteries DI and DDI. The only global parameter, AI, showed a high repeatability and the overall best correlations with AIX and PWV. PMID:26291079

School and Behavioral Outcomes Among Inner City Children: Five-Year Follow-Up.

PubMed

Kim, Seijeoung; Mazza, Jessica; Zwanziger, Jack; Henry, David

2014-10-01

Educational achievement is a key determinant of future life chances, but children growing up in poverty tend to do worse by many academic measures. Family, school, and neighborhood contextual characteristics may affect academic outcomes. In an attempt to explore neighborhood and individual level factors, we performed multilevel analyses to explain child's behavioral problems, repeat grade, average math and reading scores. Outcome measures were associated with specific neighborhood characteristics, above and beyond the effect of student/family level factors. The findings warrant further consideration of ecological interventions aiming to improve academic and behavioral outcomes of children living in poverty.

Using Hypnosis to Enhance Learning Second Language Vocabulary.

PubMed

Çetin, Yakup; Çimen, O Arda; Yetkiner, Zeynep Ebrar

2016-04-01

In this article, we measure the effects of hypnosis and suggestions for learning second language vocabulary. Participants (N = 70) were randomly assigned to a hypnosis or a control group. They were pre-tested, and then presented 21 Spanish words, post-tested immediately and 1 week later. The data were analyzed using repeated measures analysis of variance with group (experimental versus control) as the between-subjects factor, and time as the within-subjects factor. The experimental group performed significantly better in both tests. Our results indicate that hypnosis is beneficial for second language vocabulary learning and retrieval.

Psychosocial factors associated with failure to use contraception among adolescents with repeat pregnancies in Puerto Rico.

PubMed

Colón, Malieri; Martínez, Rosa; Tulla, Michelle; Pérez, José; Santaella, Yadiris; Laras, Linda

2014-01-01

Social, medical, psychological and economic problems are often associated to teen pregnancy. This is a reality worldwide; Puerto Rico is not an exception, documented in statistics and previous research projects. There are many risks associated with pregnancies among adolescents, including increased maternal morbidity and infant morbidity. In Puerto Rico, the adolescent repeat births reed are 22% for a second child and 6% for a third child. Repeated teen pregnancy has a higher than expected incidence; therefore the investigation of psychosocial factors associated with failure to use contraception is needed,especially to address the intervention at clinics with this population of different needs, mainly when these patients with repeated teen pregnancies have been through the health care system already. The project is a cross sectional survey study, seventy articipants between 12-19 years of age who attended obstetrics or postpartum clinics at an adult University Hospital. A self-administered questionnaire included some psychosocial factors that have been associated withthe failure to use contraceptives as well as demographics tion, education, socioeconomic status and support system. Their partner's age ranged from 15 to 38 years of age. Most participants lived with their partner. Their main activity at the time of the study was housework. Most had left school beforebecoming pregnant and received government help. Of all participants, a small number was legally married. The lack of use of contraceptive was found to be significantly associated to partner (p < 0.05). The lack of contraceptive use is a key factor in adolescent pregnancy. It is expected that this data can be helpful for documentation and intervention measurements something canbe done at an educational level, family planning and medical care.

Behaviour in captivity predicts some aspects of natural behaviour, but not others, in a wild cricket population

PubMed Central

Fisher, David N.; James, Adèle; Rodríguez-Muñoz, Rolando; Tregenza, Tom

2015-01-01

Examining the relevance of ‘animal personality’ involves linking consistent among- and within-individual behavioural variation to fitness in the wild. Studies aiming to do this typically assay personality in captivity and rely on the assumption that measures of traits in the laboratory reflect their expression in nature. We examined this rarely tested assumption by comparing laboratory and field measurements of the behaviour of wild field crickets (Gryllus campestris) by continuously monitoring individual behaviour in nature, and repeatedly capturing the same individuals and measuring their behaviour in captivity. We focused on three traits that are frequently examined in personality studies: shyness, activity and exploration. All of them showed repeatability in the laboratory. Laboratory activity and exploration predicted the expression of their equivalent behaviours in the wild, but shyness did not. Traits in the wild were predictably influenced by environmental factors such as temperature and sunlight, but only activity showed appreciable within-individual repeatability. This suggests that some behaviours typically studied as personality traits can be accurately assayed in captivity, but the expression of others may be highly context-specific. Our results highlight the importance of validating the relevance of laboratory behavioural assays to analogous traits measured in the wild. PMID:26019161

Repeat Pregnancy among Urban Adolescents: Sociodemographic, Family, and Health Factors.

ERIC Educational Resources Information Center

Coard, Stephanie Irby; Nitz, Katherine; Felice, Marianne E.

2000-01-01

Examines sociodemographic, family, and health factors associated with repeat pregnancy in a clinical sample of urban, first-time mothers. Results indicate that postpartum contraceptive method was associated with repeat pregnancy at year one; contraceptive use, maternal age, history of miscarriages, and postpartum contraceptive method were…

Repeatability of Central Corneal Thickness Measurement Using Rotating Scheimpflug Camera in Dry and Normal Eyes.

PubMed

Lee, Jong-Hyuck; Kim, Jae Hyuck; Kim, Sun Woong

2017-02-27

To compare the repeatability of central corneal thickness (CCT) measurement using the Pentacam between dry eyes and healthy eyes, as well as to investigate the effect of artificial tears on CCT measurement. The corneal thicknesses of 34 patients with dry eye and 28 healthy subjects were measured using the Pentacam. One eye from each subject was assigned randomly to a repeatability test, wherein a single operator performed three successive CCT measurements time points-before and 5 min after instillation of one artificial teardrop. The repeatability of measurements was assessed using the coefficient of repeatability and the intraclass correlation coefficient. The coefficient of repeatability values of the CCT measurements in dry and healthy eyes were 24.36 and 10.69 μm before instillation, and 16.85 and 9.72 μm after instillation, respectively. The intraclass correlation coefficient was higher in healthy eyes than that of in dry eyes (0.987 vs. 0.891), and it had improved significantly in dry eyes (0.948) after instillation of one artificial teardrop. The CCT measurement fluctuated in dry eyes (repeated-measures analysis of variance, P<0.001), whereas no significant changes were detected in healthy eyes, either before or after artificial tear instillation. Central corneal thickness measurement is less repeatable in dry eyes than in healthy eyes. Artificial tears improve the repeatability of CCT measurements obtained using the Pentacam in dry eyes.

Association of elevated blood pressure and impaired vasorelaxation in experimental Sprague-Dawley rats fed with heated vegetable oil

PubMed Central

2010-01-01

Background Poor control of blood pressure leads to hypertension which is a major risk factor for development of cardiovascular disease. The present study aimed to explore possible mechanisms of elevation in blood pressure following consumption of heated vegetable oil. Methods Forty-two male Sprague-Dawley rats were equally divided into six groups: Group I (control) - normal rat chow, Group II - fresh soy oil, Group III - soy oil heated once, Group IV - soy oil heated twice, Group V - soy oil heated five times, Group VI - soy oil heated ten times. Blood pressure was measured at the baseline level and at a monthly interval for six months. Plasma nitric oxide, heme oxygenase and angiotensin-converting enzyme levels were measured prior to treatment, at month-three and month-six later. At the end of treatment, the rats were sacrificed and thoracic aortas were taken for measurement of vascular reactivity. Results Blood pressure increased significantly (p < 0.01) in the repeatedly heated oil groups compared to the control and fresh soy oil groups. Consumption of diet containing repeatedly heated oil resulted higher plasma angiotensin-converting enzyme level and lower nitric oxide content and heme oxygenase concentration. Reheated soy oil groups exhibited attenuated relaxation in response to acetylcholine or sodium nitroprusside, and greater contraction to phenylephrine. Conclusion As a result of consumption of repeatedly heated soy oil, an elevation in blood pressure was observed which may be due to the quantitative changes in endothelium dependent and independent factors including enzymes directly involved in the regulation of blood pressure. PMID:20573259

Reliability of vascular geometry factors derived from clinical MRA

NASA Astrophysics Data System (ADS)

Bijari, Payam B.; Antiga, Luca; Steinman, David A.

2009-02-01

Recent work from our group has demonstrated that the amount of disturbed flow at the carotid bifurcation, believed to be a local risk factor for carotid atherosclerosis, can be predicted from luminal geometric factors. The next step along the way to a large-scale retrospective or prospective imaging study of such local risk factors for atherosclerosis is to investigate whether these geometric features are reproducible and accurate from routine 3D contrast-enhanced magnetic resonance angiography (CEMRA) using a fast and practical method of extraction. Motivated by this fact, we examined the reproducibility of multiple geometric features that are believed important in atherosclerosis risk assessment. We reconstructed three-dimensional carotid bifurcations from 15 clinical study participants who had previously undergone baseline and repeat CEMRA acquisitions. Certain geometric factors were extracted and compared between the baseline and the repeat scan. As the spatial resolution of the CEMRA data was noticeably coarse and anisotropic, we also investigated whether this might affect the measurement of the same geometric risk factors by simulating the CEMRA acquisition for 15 normal carotid bifurcations previously acquired at high resolution. Our results show that the extracted geometric factors are reproducible and faithful, with intra-subject uncertainties well below inter-subject variabilities. More importantly, these geometric risk factors can be extracted consistently and quickly for potential use as disturbed flow predictors.

Interobserver repeatability of measurements on computed tomography images of lax canine hip joints from youth to maturity.

PubMed

Lopez, Mandi J; Davis, Kechia M; Jeffrey-Borger, Susan L; Markel, Mark D; Rettenmund, Christy

2009-12-01

To determine interobserver repeatability of measurements on computed tomography (CT) images of lax canine hip joints at different ages and in the presence of degenerative joint disease at maturity. Longitudinal observational investigation. Sibling crossbreed hounds. Pelvic CT was performed at 20, 24, 32, 48, 68, and 104 weeks of age. Measures were performed on 3 contiguous two-dimensional (2D) transverse CT images of both hips at each time point by 3 investigators. Center-edge angle (CEA), horizontal toit externe angle (HTEA), ventral (VASA), dorsal (DASA), and horizontal (HASA) acetabular sector angles, acetabular index (AI), and percent femoral head coverage (CPC) were measured. Interobserver repeatability was quantified with the intraclass correlation coefficient (ICC). Satisfactory repeatability was considered when ICC >or=0.75. DASA, CEA, and CPC were repeatable in all age groups. HASA and HTEA were repeatable for all but 1 time point. At 20 weeks of age, all measures but AI were repeatable, and at 104 weeks of age, DASA, CEA, CPC, and HASA were repeatable. Measures were repeatable in hips with and without degenerative changes with the exceptions of AI and HASA in normal hips and VASA and HTEA in osteoarthritic hips. Most 2D CT measurements examined were repeatable regardless of age or joint disease. Two-dimensional CT measures may augment current techniques for assessing joint changes in lax canine hips.

Comparison of central corneal thickness measurements by rotating Scheimpflug camera, ultrasonic pachymetry, and scanning-slit corneal topography.

PubMed

Amano, Shiro; Honda, Norihiko; Amano, Yuki; Yamagami, Satoru; Miyai, Takashi; Samejima, Tomokazu; Ogata, Miyuki; Miyata, Kazunori

2006-06-01

To compare central corneal thickness measurements and their reproducibility when taken by a rotating Scheimpflug camera, ultrasonic pachymetry, and scanning-slit corneal topography/pachymetry. Experimental study. Seventy-four eyes of 64 subjects without ocular abnormalities other than cataract. Corneal thickness measurements were compared among the 3 methods in 54 eyes of 54 subjects. Two sets of measurements were repeated by a single examiner for each pachymetry in another 10 eyes of 5 subjects, and the intraexaminer repeatability was assessed as the absolute difference of the first and second measurements. Two experienced examiners took one measurement for each pachymetry in another 10 eyes of 5 subjects, and the interexaminer reproducibility was assessed as the absolute difference of the 2 measurements of the first and second examiners. Central corneal thickness measurements by the 3 methods, absolute difference of the first and second measurements by a single examiner, absolute difference of the 2 measurements by 2 examiners, and relative amount of variation. The average measurements of central corneal thickness by a rotating Scheimpflug camera, scanning-slit topography, and ultrasonic pachymetry were 538+/-31.3 microm, 541+/-40.7 microm, and 545+/-31.3 microm, respectively. There were no statistically significant differences in the measurement results among the 3 methods (P = 0.569, repeated-measures analysis of variance). There was a significant linear correlation between the rotating Scheimpflug camera and ultrasonic pachymetry (r = 0.908, P<0.0001), rotating Scheimpflug camera and scanning-slit topography (r = 0.930, P<0.0001), and ultrasonic pachymetry and scanning-slit topography (r = 0.887, P<0.0001). Ultrasonic pachymetry had the smallest intraexaminer variability, and scanning-slit topography had the largest intraexaminer variability among the 3 methods. There were similar variations in interexaminer reproducibility among the 3 methods. Mean corneal thicknesses were comparable among rotating Scheimpflug camera, ultrasonic pachymetry, and scanning-slit topography with the acoustic equivalent correction factor. The measurements of the 3 instruments had significant linear correlations with one another, and all methods had highly satisfactory measurement repeatability.

The molecular mechanism of nuclear transport revealed by atomic-scale measurements

PubMed Central

Hough, Loren E; Dutta, Kaushik; Sparks, Samuel; Temel, Deniz B; Kamal, Alia; Tetenbaum-Novatt, Jaclyn; Rout, Michael P; Cowburn, David

2015-01-01

Nuclear pore complexes (NPCs) form a selective filter that allows the rapid passage of transport factors (TFs) and their cargoes across the nuclear envelope, while blocking the passage of other macromolecules. Intrinsically disordered proteins (IDPs) containing phenylalanyl-glycyl (FG)-rich repeats line the pore and interact with TFs. However, the reason that transport can be both fast and specific remains undetermined, through lack of atomic-scale information on the behavior of FGs and their interaction with TFs. We used nuclear magnetic resonance spectroscopy to address these issues. We show that FG repeats are highly dynamic IDPs, stabilized by the cellular environment. Fast transport of TFs is supported because the rapid motion of FG motifs allows them to exchange on and off TFs extremely quickly through transient interactions. Because TFs uniquely carry multiple pockets for FG repeats, only they can form the many frequent interactions needed for specific passage between FG repeats to cross the NPC. DOI: http://dx.doi.org/10.7554/eLife.10027.001 PMID:26371551

Masonry fireplace emissions test method: Repeatability and sensitivity to fueling protocol.

PubMed

Stern, C H; Jaasma, D R; Champion, M R

1993-03-01

A test method for masonry fireplaces has been evaluated during testing on six masonry fireplace configurations. The method determines carbon monoxide and particulate matter emission rates (g/h) and factors (g/kg) and does not require weighing of the appliance to determine the timing of fuel loading.The intralaboratory repeatability of the test method has been determined from multiple tests on the six fireplaces. For the tested fireplaces, the ratio of the highest to lowest measured PM rate averaged 1.17 and in no case was greater than 1.32. The data suggest that some of the variation is due to differences in fuel properties.The influence of fueling protocol on emissions has also been studied. A modified fueling protocol, tested in large and small fireplaces, reduced CO and PM emission factors by roughly 40% and reduced CO and PM rates from 0 to 30%. For both of these fireplaces, emission rates were less sensitive to fueling protocol than emission factors.

Central gene expression changes associated with enhanced neuroendocrine and autonomic response habituation to repeated noise stress after voluntary wheel running in rats

PubMed Central

Sasse, Sarah K.; Nyhuis, Tara J.; Masini, Cher V.; Day, Heidi E. W.; Campeau, Serge

2013-01-01

Accumulating evidence indicates that regular physical exercise benefits health in part by counteracting some of the negative physiological impacts of stress. While some studies identified reductions in some measures of acute stress responses with prior exercise, limited data were available concerning effects on cardiovascular function, and reported effects on hypothalamic-pituitary-adrenocortical (HPA) axis responses were largely inconsistent. Given that exposure to repeated or prolonged stress is strongly implicated in the precipitation and exacerbation of illness, we proposed the novel hypothesis that physical exercise might facilitate adaptation to repeated stress, and subsequently demonstrated significant enhancement of both HPA axis (glucocorticoid) and cardiovascular (tachycardia) response habituation to repeated noise stress in rats with long-term access to running wheels compared to sedentary controls. Stress habituation has been attributed to modifications of brain circuits, but the specific sites of adaptation and the molecular changes driving its expression remain unclear. Here, in situ hybridization histochemistry was used to examine regulation of select stress-associated signaling systems in brain regions representing likely candidates to underlie exercise-enhanced stress habituation. Analyzed brains were collected from active (6 weeks of wheel running) and sedentary rats following control, acute, or repeated noise exposures that induced a significantly faster rate of glucocorticoid response habituation in active animals but preserved acute noise responsiveness. Nearly identical experimental manipulations also induce a faster rate of cardiovascular response habituation in exercised, repeatedly stressed rats. The observed regulation of the corticotropin-releasing factor and brain-derived neurotrophic factor systems across several brain regions suggests widespread effects of voluntary exercise on central functions and related adaptations to stress across multiple response modalities. PMID:24324441

Assessing the Quality of Parent-Teacher Relationships for Students with ADHD

ERIC Educational Resources Information Center

Mautone, Jennifer A.; Marcelle, Enitan; Tresco, Katy E.; Power, Thomas J.

2015-01-01

Family involvement in education, including the quality of family-school communication, has been demonstrated repeatedly to have a substantial effect on child development and success in school; however, measures of this construct are limited. The purpose this study was to examine the factor structure and concurrent validity of the Quality of the…

Modeling containment of large wildfires using generalized linear mixed-model analysis

Treesearch

Mark Finney; Isaac C. Grenfell; Charles W. McHugh

2009-01-01

Billions of dollars are spent annually in the United States to contain large wildland fires, but the factors contributing to suppression success remain poorly understood. We used a regression model (generalized linear mixed-model) to model containment probability of individual fires, assuming that containment was a repeated-measures problem (fixed effect) and...

Repeatability Evaluation of a Contrast Sensitivity System for Transfer to the Eye Clinic

NASA Astrophysics Data System (ADS)

Alcalde, N. G.; Castillo, L. R.; Filgueira, C. Paz; Colombo, E. M.

2016-04-01

The Contrast Sensitivity Function (CSF) is a valuable tool which can be used to characterize functional vision and also for the diagnosis and management of patients with different eye diseases. In spite of its usefulness, the CSF is currently hardly ever used in clinical practice. The aim of this study was to validate the use of the system called FVC-100 (Tecnovinc-UNT-CONICET, Argentina), which calculates the CSF, in order to transfer this important tool to ophthalmological clinics. The validation was carried out through the design of a repeatability test and the subsequent analysis of the results. Furthermore, we evaluated the impact of different factors influencing the repeatability of the measurements such as age and previous training. The tests were based on the discrimination of sinusoidal gratings for different spatial frequencies (1, 4 and 12 c/°) in both eyes of 12 people, aged between 20 and 70. The results show that the calculated values of SC of each subject have a high repeatability and are not dependent on age or training. These results allow us to conclude positively regarding the effectiveness of the FVC-100, and to validate its use in clinics for the calculation of the FSC as a standard measure of functional vision quality.

Risk factors for complications in donors at first and repeat whole blood donation: a cohort study with assessment of the impact on donor return.

PubMed

Wiersum-Osselton, Johanna C; Marijt-van der Kreek, Tanneke; Brand, Anneke; Veldhuizen, Ingrid; van der Bom, Johanna G; de Kort, Wim

2014-01-01

First-time donation is among recognised risk factors for vasovagal reactions to blood donation and reactions are known to reduce donor return. We assessed associations between potential risk factors and vasovagal reactions and needle-related complications in first-time whole blood donation in comparison to repeat donation and analysed the impact of complications on donor return. We performed a cohort study on whole blood donations in The Netherlands from 1/1/2010 to 31/12/2010 using data extracted from the blood service information system. Donation data up to 31/12/2011 were used to ascertain donor return. In 2010 28,786 donors made first whole blood donations and there were 522,958 repeat donations. Vasovagal reactions occurred in 3.9% of first donations by males and 3.5% of first donations by females compared to in 0.2% and 0.6%, respectively, of repeat donations. Associations of vasovagal reactions with other factors including age, body weight, systolic and diastolic blood pressure were similar in first-time and repeat donors. Needle-related complications occurred in 0.2% of male and 0.5% of female first-time donations and in 0.1% and 0.3%, respectively, of repeat donations. Among first-time donors, the return rate within 1 year was 82% following an uncomplicated first donation, but 55% and 61% following vasovagal reactions and needle-related complications, respectively; the corresponding percentages among repeat donors were 86%, 58% and 82%. Among first-time donors, females suffered less than males from vasovagal reactions. Other risk factors had similar associations among first-time and repeat donors. Vasovagal reactions and needle-related complications in both first-time and repeat donors are followed by reduced donor return.

The potential benefits of repeated measure experiments for fish disease-challenge host-pathogen investigations.

PubMed

Hall, L Malcolm; Collins, Catherine; Collet, Bertrand

2018-02-02

The utility of molecular response data arising from in-vivo single and repeated measure fish disease-challenge experiments is compared. An in-silico 'experiment' involving the generation of two imaginary immune-molecule quantity response profiles over time for individual animals was carried out. Daily 'observed' molecule quantities were drawn from the 'known' individual response profiles to mimic the results of single and repeated measurement. The results indicate that repeated measure experiments are required to infer individual level response profiles, and that these experiments also provide more accurate summary statistics and data more suited to inferring the dependent ordering of the molecular response. Additionally repeated measure experiments utilise fewer animals than single measure experiments. These results are described alongside a discussion of experimental methodological issues pertinent to the adoption of aquatic animal repeated measure experimental designs. We conclude that investigators need to take particular care when making inferences from single measure experiments and that serious consideration should be given to using repeated measure experiments for in-vivo fish disease-challenge investigations. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

[Analysis of binary classification repeated measurement data with GEE and GLMMs using SPSS software].

PubMed

An, Shengli; Zhang, Yanhong; Chen, Zheng

2012-12-01

To analyze binary classification repeated measurement data with generalized estimating equations (GEE) and generalized linear mixed models (GLMMs) using SPSS19.0. GEE and GLMMs models were tested using binary classification repeated measurement data sample using SPSS19.0. Compared with SAS, SPSS19.0 allowed convenient analysis of categorical repeated measurement data using GEE and GLMMs.

Duct Leakage Repeatability Testing

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

Walker, Iain; Sherman, Max

2014-08-01

The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques for duct leakage using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards. The three duct leak measurement methods assessed in this report are the twomore » duct pressurization methods that are commonly used by many practitioners and the DeltaQ technique. These are methods B, C and A, respectively of the ASTM E1554 standard. Although it would be useful to evaluate other duct leak test methods, this study focused on those test methods that are commonly used and are required in various test standards, such as BPI (2010), RESNET (2014), ASHRAE 62.2 (2013), California Title 24 (CEC 2012), DOE Weatherization and many other energy efficiency programs.« less

Evaluation of a semi-automated computer algorithm for measuring total fat and visceral fat content in lambs undergoing in vivo whole body computed tomography.

PubMed

Rosenblatt, Alana J; Scrivani, Peter V; Boisclair, Yves R; Reeves, Anthony P; Ramos-Nieves, Jose M; Xie, Yiting; Erb, Hollis N

2017-10-01

Computed tomography (CT) is a suitable tool for measuring body fat, since it is non-destructive and can be used to differentiate metabolically active visceral fat from total body fat. Whole body analysis of body fat is likely to be more accurate than single CT slice estimates of body fat. The aim of this study was to assess the agreement between semi-automated computer analysis of whole body volumetric CT data and conventional proximate (chemical) analysis of body fat in lambs. Data were collected prospectively from 12 lambs that underwent duplicate whole body CT, followed by slaughter and carcass analysis by dissection and chemical analysis. Agreement between methods for quantification of total and visceral fat was assessed by Bland-Altman plot analysis. The repeatability of CT was assessed for these measures using the mean difference of duplicated measures. When compared to chemical analysis, CT systematically underestimated total and visceral fat contents by more than 10% of the mean fat weight. Therefore, carcass analysis and semi-automated CT computer measurements were not interchangeable for quantifying body fat content without the use of a correction factor. CT acquisition was repeatable, with a mean difference of repeated measures being close to zero. Therefore, uncorrected whole body CT might have an application for assessment of relative changes in fat content, especially in growing lambs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mystery shopping and coaching as a form of audit and feedback to improve community pharmacy management of non-prescription medicine requests: an intervention study

PubMed Central

Schneider, Carl Richard; Naughtin, Clare Louise; Wilson, Frances; de Almeida Neto, Abilio Cesar; Moles, Rebekah Jane

2017-01-01

Objectives To determine whether repeated mystery shopping visits with feedback improve pharmacy performance over nine visits and to determine what factors predict an appropriate outcome. Design Prospective, parallel, repeated intervention, repeated measures mystery shopping (pseudopatient) design. Setting Thirty-six community pharmacies in metropolitan Sydney, Australia in March–October 2015. Participants Sixty-one University of Sydney pharmacy undergraduates acted as mystery shoppers. Students enrolled in their third year of Bachelor of Pharmacy in 2015 were eligible to participate. Any community pharmacy in the Sydney metropolitan region was eligible to take part and was selected through convenience sampling. Intervention Repeated mystery shopping with immediate feedback and coaching. Outcome measures Outcome for each given scenario (appropriate or not) and questioning scores for each interaction. Results Five hundred and twenty-one visits were analysed, of which 54% resulted in an appropriate outcome. Questioning scores and the proportion of interactions resulting in an appropriate outcome significantly improved over time (P<0.001). Involvement of pharmacists, visit number, increased questioning score and the prescribed scenario were predictors of an appropriate outcome (P=0.008, P=0.022, P<0.001 and P<0.001, respectively). Interactions involving a pharmacist had greater scores than those without (P<0.001). Conclusions Repeated mystery shopping visits with feedback were associated with improved pharmacy performance over time. Future work should focus on the role of non-pharmacist staff and design interventions accordingly. PMID:29247115

Child Weight Growth Trajectory and its Determinants in a Sample of Iranian Children from Birth until 2 Years of Age

PubMed Central

Hosseini, Sayed-Mohsen; Maracy, Mohamad-Reza; Sarrafzade, Sheida; Kelishadi, Roya

2014-01-01

Background: Growth is one of the most important indices in child health. The best and most effective way to investigate child health is measuring the physical growth indices such as weight, height and head circumference. Among these measures, weight growth is the simplest and the most effective way to determine child growth status. Weight trend at a given age is the result of cumulative growth experience, whereas growth velocity represents what is happening at the time. Methods: This longitudinal study was conducted among 606 children repeatedly measured from birth until 2 years of age. We used linear mixed model to analyze repeated measures and to determine factors affecting the growth trajectory. LOWESS smooth curve was used to draw velocity curves. Results: Gender, child rank, birth status and feeding mode had a significant effect on weight trajectory. Boys had higher weight during the study. Infants with exclusive breast feeding had higher weight than other infants. Boys had higher growth velocity up to age 6 month. Breast fed infants had higher growth velocity up to 6 month, but thereafter the velocity was higher in other infants. Conclusions: Many of the studies have investigated child growth, but most of them used cross-sectional design. In this study, we used longitudinal method to determine effective factors on weight trend in children from birth until 2-year-old. The effects of perinatal factors on further growth should be considered for prevention of growth disorders and their late complications. PMID:24829720

An automated walk-over weighing system as a tool for measuring liveweight change in lactating dairy cows.

PubMed

Dickinson, R A; Morton, J M; Beggs, D S; Anderson, G A; Pyman, M F; Mansell, P D; Blackwood, C B

2013-07-01

Automated walk-over weighing systems can be used to monitor liveweights of cattle. Minimal literature exists to describe agreement between automated and static scales, and no known studies describe repeatability when used for daily measurements of dairy cows. This study establishes the repeatability of an automated walk-over cattle-weighing system, and agreement with static electronic scales, when used in a commercial dairy herd to weigh lactating cows. Forty-six lactating dairy cows from a seasonal calving, pasture-based dairy herd in southwest Victoria, Australia, were weighed once using a set of static scales and repeatedly using an automated walk-over weighing system at the exit of a rotary dairy. Substantial agreement was observed between the automated and static scales when assessed using Lin's concordance correlation coefficient. Weights measured by the automated walkover scales were within 5% of those measured by the static scales in 96% of weighings. Bland and Altman's 95% limits of agreement were -23.3 to 43.6 kg, a range of 66.9 kg. The 95% repeatability coefficient for automated weighings was 46.3 kg. Removal of a single outlier from the data set increased Lin's concordance coefficient, narrowed Bland and Altman's 95% limits of agreement to a range of 32.5 kg, and reduced the 95% repeatability coefficient to 18.7 kg. Cow misbehavior during walk-over weighing accounted for many of the larger weight discrepancies. The automated walk-over weighing system showed substantial agreement with the static scales when assessed using Lin's concordance correlation coefficient. This contrasted with limited agreement when assessed using Bland and Altman's method, largely due to poor repeatability. This suggests the automated weighing system is inadequate for detecting small liveweight differences in individual cows based on comparisons of single weights. Misbehaviors and other factors can result in the recording of spurious values on walk-over scales. Excluding outlier weights and comparing means of 7 consecutive daily weights may improve agreement sufficiently to allow meaningful assessment of small short-term changes in automated weights in individuals and groups of cows. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Optically stimulated luminescence in vivo dosimetry for radiotherapy: physical characterization and clinical measurements in (60)Co beams.

PubMed

Mrčela, I; Bokulić, T; Izewska, J; Budanec, M; Fröbe, A; Kusić, Z

2011-09-21

A commercial optically stimulated luminescence (OSL) dosimetry system was investigated for in vivo dosimetry in radiation therapy. Dosimetric characteristics of InLight dot dosimeters and a microStar reader (Landauer Inc.) were tested in (60)Co beams. The reading uncertainty of a single dosimeter was 0.6%. The reproducibility of a set of dosimeters after a single irradiation was 1.6%, while in repeated irradiations of the same dosimeters it was found to be 3.5%. When OSL dosimeters were optically bleached between exposures, the reproducibility of repeated measurements improved to 1.0%. Dosimeters were calibrated for the entrance dose measurements and a full set of correction factors was determined. A pilot patient study that followed phantom validation testing included more than 100 measured fields with a mean relative difference of the measured entrance dose from the expected dose of 0.8% and the standard deviation of 2.5%. In conclusion, these results demonstrate that OSL dot dosimeters represent a valid alternative to already established in vivo dosimetry systems.

Optically stimulated luminescence in vivo dosimetry for radiotherapy: physical characterization and clinical measurements in 60Co beams

NASA Astrophysics Data System (ADS)

Mrčela, I.; Bokulić, T.; Izewska, J.; Budanec, M.; Fröbe, A.; Kusić, Z.

2011-09-01

A commercial optically stimulated luminescence (OSL) dosimetry system was investigated for in vivo dosimetry in radiation therapy. Dosimetric characteristics of InLight dot dosimeters and a microStar reader (Landauer Inc.) were tested in 60Co beams. The reading uncertainty of a single dosimeter was 0.6%. The reproducibility of a set of dosimeters after a single irradiation was 1.6%, while in repeated irradiations of the same dosimeters it was found to be 3.5%. When OSL dosimeters were optically bleached between exposures, the reproducibility of repeated measurements improved to 1.0%. Dosimeters were calibrated for the entrance dose measurements and a full set of correction factors was determined. A pilot patient study that followed phantom validation testing included more than 100 measured fields with a mean relative difference of the measured entrance dose from the expected dose of 0.8% and the standard deviation of 2.5%. In conclusion, these results demonstrate that OSL dot dosimeters represent a valid alternative to already established in vivo dosimetry systems.

Evidence of Circadian Rhythm, Oxygen Regulation Capacity, Metabolic Repeatability and Positive Correlations between Forced and Spontaneous Maximal Metabolic Rates in Lake Sturgeon Acipenser fulvescens

PubMed Central

Svendsen, Jon C.; Genz, Janet; Anderson, W. Gary; Stol, Jennifer A.; Watkinson, Douglas A.; Enders, Eva C.

2014-01-01

Animal metabolic rate is variable and may be affected by endogenous and exogenous factors, but such relationships remain poorly understood in many primitive fishes, including members of the family Acipenseridae (sturgeons). Using juvenile lake sturgeon (Acipenser fulvescens), the objective of this study was to test four hypotheses: 1) A. fulvescens exhibits a circadian rhythm influencing metabolic rate and behaviour; 2) A. fulvescens has the capacity to regulate metabolic rate when exposed to environmental hypoxia; 3) measurements of forced maximum metabolic rate (MMRF) are repeatable in individual fish; and 4) MMRF correlates positively with spontaneous maximum metabolic rate (MMRS). Metabolic rates were measured using intermittent flow respirometry, and a standard chase protocol was employed to elicit MMRF. Trials lasting 24 h were used to measure standard metabolic rate (SMR) and MMRS. Repeatability and correlations between MMRF and MMRS were analyzed using residual body mass corrected values. Results revealed that A. fulvescens exhibit a circadian rhythm in metabolic rate, with metabolism peaking at dawn. SMR was unaffected by hypoxia (30% air saturation (O2sat)), demonstrating oxygen regulation. In contrast, MMRF was affected by hypoxia and decreased across the range from 100% O2sat to 70% O2sat. MMRF was repeatable in individual fish, and MMRF correlated positively with MMRS, but the relationships between MMRF and MMRS were only revealed in fish exposed to hypoxia or 24 h constant light (i.e. environmental stressor). Our study provides evidence that the physiology of A. fulvescens is influenced by a circadian rhythm and suggests that A. fulvescens is an oxygen regulator, like most teleost fish. Finally, metabolic repeatability and positive correlations between MMRF and MMRS support the conjecture that MMRF represents a measure of organism performance that could be a target of natural selection. PMID:24718688

Investigating Experimental Effects within the Framework of Structural Equation Modeling: An Example with Effects on Both Error Scores and Reaction Times

ERIC Educational Resources Information Center

Schweizer, Karl

2008-01-01

Structural equation modeling provides the framework for investigating experimental effects on the basis of variances and covariances in repeated measurements. A special type of confirmatory factor analysis as part of this framework enables the appropriate representation of the experimental effect and the separation of experimental and…

A Study of Repeated Wrist Temperature of Sixth, Seventh, and Eighth Graders.

ERIC Educational Resources Information Center

Matthews, Doris B.; Quinn, Jimmy L.

While evidence exists that a person's peripheral temperature responds to his state of arousal or stress, it also responds to other environmental factors. Wrist temperature has been found to vary with ambient temperature, and to increase during the school day. Before wrist temperature can be established as a valid measure of anxiety, stress, or…

Effective Use of Multimedia Presentations to Maximize Learning within High School Science Classrooms

ERIC Educational Resources Information Center

Rapp, Eric

2013-01-01

This research used an evidenced-based experimental 2 x 2 factorial design General Linear Model with Repeated Measures Analysis of Covariance (RMANCOVA). For this analysis, time served as the within-subjects factor while treatment group (i.e., static and signaling, dynamic and signaling, static without signaling, and dynamic without signaling)…

Development of microcomputer-based mental acuity tests for repeated-measures studies

NASA Technical Reports Server (NTRS)

Kennedy, R. S.; Wilkes, R. L.; Baltzley, D. R.; Fowlkes, J. E.

1990-01-01

The purpose of this report is to detail the development of the Automated Performance Test System (APTS), a computer battery of mental acuity tests that can be used to assess human performance in the presence of toxic elements and environmental stressors. There were four objectives in the development of APTS. First, the technical requirements for developing APTS followed the tenets of the classical theory of mental tests which requires that tests meet set criteria like stability and reliability (the lack of which constitutes insensitivity). To be employed in the study of the exotic conditions of protracted space flight, a battery with multiple parallel forms is required. The second criteria was for the battery to have factorial multidimensionality and the third was for the battery to be sensitive to factors known to compromise performance. A fourth objective was for the tests to converge on the abilities entailed in mission specialist tasks. A series of studies is reported in which candidate APTS tests were subjected to an examination of their psychometric properties for repeated-measures testing. From this work, tests were selected that possessed the requisite metric properties of stability, reliability, and factor richness. In addition, studies are reported which demonstrate the predictive validity of the tests to holistic measures of intelligence.

Long-term results of repeated anti-vascular endothelial growth factor therapy in eyes with retinal pigment epithelial tears.

PubMed

Moreira, Carlos A; Arana, Luis A; Zago, Rommel J

2013-02-01

To evaluate the long-term results of retinal pigment epithelium tears in eyes treated with repeated anti-vascular endothelial growth factor (VEGF) therapy. Five patients with retinal pigment epithelial tears (without foveal center involvement) after anti-VEGF injection were studied retrospectively. Mean follow-up time was 52 months, with measurements of visual acuity and evaluation of macular findings by angiography and optical coherence tomography during this period. All eyes had a persistent submacular neovascular membrane 30 days after the tear. An anti-VEGF drug was reinjected until the membranes stopped leaking. The mean initial visual acuity immediately after the tear was 20/160, and the mean final visual acuity was 20/60. The number of anti-VEGF reinjections varied from two to eight during the follow-up period. Long-term optical coherence tomography analysis showed reduced fluid and remodeling of the torn retinal pigment epithelium. Long-term visual results with repeated anti-VEGF therapy are not as devastating as suggested previously. Visual acuity and metamorphopsia improve with time as long as the neovascular membrane is inactive. Optical coherence tomography changes in the macular area reflect the visual acuity improvement.

Efficacy of Repeated Botulinum Toxin Type A Injections for Spastic Equinus in Children with Cerebral Palsy-A Secondary Analysis of the Randomized Clinical Trial.

PubMed

Hong, Bo Young; Chang, Hyun Jung; Lee, Sang-Jee; Lee, Soyoung; Park, Joo Hyun; Kwon, Jeong-Yi

2017-08-21

Botulinum toxin A is considered an important tool to control spasticity in children with cerebral palsy. Several factors are known to affect the efficacy of botulinum toxin, such as dosage, appropriate muscle selection and application, age, and accompanying therapy. A multicenter, double-blind, randomized, prospective phase III clinical trial of botulinum toxin A for the treatment of dynamic equinus in 144 children with cerebral palsy was performed to compare the efficacies of letibotulinumtoxin A and onabotulinumtoxin A. Secondary analyses were performed to evaluate factors that affected the outcome, focusing on the number of times injections were repeated. Effectiveness was defined as a change of 2 or more in the physician's rating scale. Multivariate regression analyses were performed with multiple variables. The first injection of botulinum toxin A significantly improved D subscale of Gross Motor Function Measure-88 scores at 3 months compared to repeated injections ( p < 0.05). After 6 months, patients who had one injection or none before the study showed significantly better outcomes than those who had more than one injection in terms of observational gait scores.

Factors associated with repeated refusal to participate in longitudinal population-based HIV surveillance in rural South Africa: an observational study, regression analyses

PubMed Central

Giordano, Katie; McGrath, Nuala; Snow, Rachel; Harlow, Siobán; Newell, Marie-Louise

2014-01-01

Background For many estimation purposes, individuals who repeatedly refuse to participate in longitudinal HIV surveillance pose a bigger threat to valid inferences than individuals who participate at least occasionally. We investigate the determinants of repeated refusal to consent to HIV testing in a population-based longitudinal surveillance in rural South Africa. Methods We used data from two years (2005 & 2006) of the annual HIV surveillance conducted by the Africa Centre for Health and Population Studies, linking the HIV surveillance data to demographic and socioeconomic data. The outcome for the analysis was “repeated refusal”. Demographic variables included sex, age, highest educational attainment, and place of residence. We also included a measure of wealth and the variable “ever had sex”. To compare the association of each variable with the outcome, unadjusted odds ratios and standard errors were estimated. Multivariable logistic regression was used to estimate adjusted odds ratios and their standard errors. Data were analyzed using STATA 10.0. Results Of 15,557 eligible individuals, 46% refused to test for HIV in both rounds. Males were significantly more likely than females to repeatedly refuse testing. Holding all other variables constant, individuals in the middle age groups were more likely to repeatedly refuse testing compared with younger and older age groups. The odds of repeated refusal increased with increasing level of education and relative wealth. People living in urban areas were significantly more likely to repeatedly refuse an HIV test than people living in peri-urban or rural areas. Compared to those who had ever had sex, both males and females who had not yet had sex were significantly more likely to refuse to participate. Conclusions The likelihood of repeated refusal to test for HIV in this longitudinal surveillance increases with education, wealth, urbanization, and primary sexual abstinence. Since the factors determining repeated HIV testing refusal are likely associated with HIV status, it is critical that selection effects are controlled for in the analysis of HIV surveillance data. Interventions to increase consent to HIV testing should consider targeting the relatively well educated and wealthy, people in urban areas, and individuals who have not yet sexually debuted. PMID:25621095

Factors affecting accuracy in the Developmental Eye Movement Test measurement for Cantonese-speaking children.

PubMed

Pang, Peter C; Lam, Carly S; Woo, George C

2010-09-01

This study aims to determine the factors affecting the accuracy in the Developmental Eye Movement (DEM) test measurement for Cantonese-speaking children. The voices of 10 Cantonese-speaking children (aged between six and eight years) undertaking the vertical test (40 numbers) of the DEM test were recorded on a digital audio recorder. These voice clips were assessed by an experienced examiner to give the DEM test times. The examiner repeated the measurement five times for each voice clip and completed all 10 voice clips from the 10 children. The average of a single measurement, the mean of two, the mean of three and the mean of five repeated measurements were then compared. Five experienced and five inexperienced examiners of the DEM test were asked to record the results from five Cantonese-speaking children by listening to the playback of prerecorded audio clips. The deviation of the results from the preset values between the two groups was compared. There is no difference between the single measurement and those obtained by mean of two, three, four or five. Both experienced and inexperienced examiners obtained a higher deviation from the preset values in the adjusted compared with the non-adjusted times in both vertical and horizontal times. Experienced examiners measured the vertical times and adjusted vertical times significantly closer to the preset values than the inexperienced examiners (paired t-test, p < 0.05). The DEM test needs to be measured only once for an accurate time measurement. Inaccurate assessment of 'reading errors' in the DEM test can increase the inaccuracy of the adjusted times. It is suggested that an audio recording of the test be made to allow reassessment of reading errors. Experience in using the DEM test yields a more accurate DEM measurement as errors are detected more easily.

[Convergent origin of repeats in genes coding for globular proteins. An analysis of the factors determining the presence of inverted and symmetrical repeats].

PubMed

Solov'ev, V V; Kel', A E; Kolchanov, N A

1989-01-01

The factors, determining the presence of inverted and symmetrical repeats in genes coding for globular proteins, have been analysed. An interesting property of genetical code has been revealed in the analysis of symmetrical repeats: the pairs of symmetrical codons corresponded to pairs of amino acids with mostly similar physical-chemical parameters. This property may explain the presence of symmetrical repeats and palindromes only in genes coding for beta-structural proteins-polypeptides, where amino acids with similar physical-chemical properties occupy symmetrical positions. A stochastic model of evolution of polynucleotide sequences has been used for analysis of inverted repeats. The modelling demonstrated that only limiting of sequences (uneven frequencies of used codons) is enough for arising of nonrandom inverted repeats in genes.

Dynamic 3D shape of the plantar surface of the foot using coded structured light: a technical report

PubMed Central

2014-01-01

Background The foot provides a crucial contribution to the balance and stability of the musculoskeletal system, and accurate foot measurements are important in applications such as designing custom insoles/footwear. With better understanding of the dynamic behavior of the foot, dynamic foot reconstruction techniques are surfacing as useful ways to properly measure the shape of the foot. This paper presents a novel design and implementation of a structured-light prototype system providing dense three dimensional (3D) measurements of the foot in motion. The input to the system is a video sequence of a foot during a single step; the output is a 3D reconstruction of the plantar surface of the foot for each frame of the input. Methods Engineering and clinical tests were carried out to test the accuracy and repeatability of the system. Accuracy experiments involved imaging a planar surface from different orientations and elevations and measuring the fitting errors of the data to a plane. Repeatability experiments were done using reconstructions from 27 different subjects, where for each one both right and left feet were reconstructed in static and dynamic conditions over two different days. Results The static accuracy of the system was found to be 0.3 mm with planar test objects. In tests with real feet, the system proved repeatable, with reconstruction differences between trials one week apart averaging 2.4 mm (static case) and 2.8 mm (dynamic case). Conclusion The results obtained in the experiments show positive accuracy and repeatability results when compared to current literature. The design also shows to be superior to the systems available in the literature in several factors. Further studies need to be done to quantify the reliability of the system in clinical environments. PMID:24456711

Dynamic 3D shape of the plantar surface of the foot using coded structured light: a technical report.

PubMed

Thabet, Ali K; Trucco, Emanuele; Salvi, Joaquim; Wang, Weijie; Abboud, Rami J

2014-01-23

The foot provides a crucial contribution to the balance and stability of the musculoskeletal system, and accurate foot measurements are important in applications such as designing custom insoles/footwear. With better understanding of the dynamic behavior of the foot, dynamic foot reconstruction techniques are surfacing as useful ways to properly measure the shape of the foot. This paper presents a novel design and implementation of a structured-light prototype system providing dense three dimensional (3D) measurements of the foot in motion. The input to the system is a video sequence of a foot during a single step; the output is a 3D reconstruction of the plantar surface of the foot for each frame of the input. Engineering and clinical tests were carried out to test the accuracy and repeatability of the system. Accuracy experiments involved imaging a planar surface from different orientations and elevations and measuring the fitting errors of the data to a plane. Repeatability experiments were done using reconstructions from 27 different subjects, where for each one both right and left feet were reconstructed in static and dynamic conditions over two different days. The static accuracy of the system was found to be 0.3 mm with planar test objects. In tests with real feet, the system proved repeatable, with reconstruction differences between trials one week apart averaging 2.4 mm (static case) and 2.8 mm (dynamic case). The results obtained in the experiments show positive accuracy and repeatability results when compared to current literature. The design also shows to be superior to the systems available in the literature in several factors. Further studies need to be done to quantify the reliability of the system in clinical environments.

The initial effects of a sustained glenohumeral postero-lateral glide during elevation on shoulder muscle activity: A repeated measures study on asymptomatic shoulders.

PubMed

Ribeiro, Daniel Cury; de Castro, Marcelo Peduzzi; Sole, Gisela; Vicenzino, Bill

2016-04-01

Manual therapy enhances pain-free range of motion and reduces pain levels, but its effect on shoulder muscle activity is unclear. This study aimed to assess the effects of a sustained glenohumeral postero-lateral glide during elevation on shoulder muscle activity. Thirty asymptomatic individuals participated in a repeated measures study of the electromyographic activity of the supraspinatus, infraspinatus, posterior deltoid, and middle deltoid. Participants performed four sets of 10 repetitions of shoulder scaption and abduction with and without a glide of the glenohumeral joint. Repeated-measures multivariate analysis of variance (MANOVA) was used to assess the effects of movement direction (scaption and abduction), and condition (with and without glide) (within-subject factors) on activity level of each muscle (dependent variables). Significant MANOVAs were followed-up with repeated-measures one-way analysis of variance. During shoulder scaption with glide, the supraspinatus showed a reduction of 4.1% maximal isometric voluntary contraction (MVIC) (95% CI 2.4, 5.8); and infraspinatus 1.3% MVIC (95% CI 0.5, 2.1). During shoulder abduction with a glide, supraspinatus presented a reduction of 2.5% MVIC (95% CI 1.1, 4.0), infraspinatus 2.1% MVIC (95% CI 1.0, 3.2), middle deltoid 2.2% MVIC (95% CI = 0.4, 4.1), posterior deltoid 2.1% MVIC (95% CI 1.3, 2.8). In asymptomatic individuals, sustained glide reduced shoulder muscle activity compared to control conditions. This might be useful in enhancing shoulder movement in clinical populations. Reductions in muscle activity might result from altered joint mechanics, including simply helping to lift the arm, and/or through changing afferent sensory input about the shoulder. Copyright © 2015 Elsevier Ltd. All rights reserved.

Oligomeric domain structure of human complement factor H by X-ray and neutron solution scattering

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

Perkins, S.J.; Nealis, A.S.; Sim, R.B.

1991-03-19

Factor H is a regulatory component of the complement system. It has a monomer M{sub r} of 150,000. Primary structure analysis shows that the polypeptide is divided into 20 homologous regions, each 60 amino acid residues long. These are independently folding domains and are termed short consensus repeats (SCRs) or complement control protein (CCP) repeats. High-flux synchrotron x-ray and neutron scatteriing studies were performed in order to define its solution structure in conditions close to physiological. The M{sub r} of factor H was determined as 250,000-320,000 to show that factor H is dimeric. The radius of gyration R{sub G} ofmore » native factor H by X-rays or by neutrons in 0% or 100% {sup 2}H{sub 2}O buffers is not measurable but is greater than 12.5 nm. Two cross-sectional radii of gyration R{sub XS-1} and R{sub XS-2} were determined as 3.0-3.1 and 1.8 nm, respectively. Analyses of the cross-sectional intensities show that factor H is composed of two distinct subunits. This model corresponds to an actual R{sub G} fo 21-23 nm. The separation between each SCR/CCP in factor H is close to 4 nm. In the solution structure of factor H, the SCR/CCP domains are in a highly extended conformation.« less

How do repeat suicide attempters differ from first timers? An exploratory record based analysis

PubMed Central

Menon, Vikas; Kattimani, Shivanand; Sarkar, Siddharth; Mathan, Kaliaperumal

2016-01-01

Background: Evidence indicates that repeat suicide attempters, as a group, may differ from 1st time attempters. The identification of repeat attempters is a powerful but underutilized clinical variable. Aims: In this research, we aimed to compare individuals with lifetime histories of multiple attempts with 1st time attempters to identify factors predictive of repeat attempts. Setting and Design: This was a retrospective record based study carried out at a teaching cum Tertiary Care Hospital in South India. Methods: Relevant data was extracted from the clinical records of 1st time attempters (n = 362) and repeat attempters (n = 61) presenting to a single Tertiary Care Center over a 4½ year period. They were compared on various sociodemographic and clinical parameters. The clinical measures included Presumptive Stressful Life Events Scale, Beck Hopelessness Scale, Coping Strategies Inventory – Short Form, and the Global Assessment of Functioning Scale. Statistical Analysis Used: First time attempters and repeaters were compared using appropriate inferential statistics. Logistic regression was used to identify independent predictors of repeat attempts. Results: The two groups did not significantly differ on sociodemographic characteristics. Repeat attempters were more likely to have given prior hints about their act (χ2 = 4.500, P = 0.034). In the final regression model, beck hopelessness score emerged as a significant predictor of repeat suicide attempts (odds ratio = 1.064, P = 0.020). Conclusion: Among suicide attempters presenting to the hospital, the presence of hopelessness is a predictor of repeat suicide attempts, independent of clinical depression. This highlights the importance of considering hopelessness in the assessment of suicidality with a view to minimize the risk of future attempts. PMID:26933353

Framework for measuring adaptive knowledge-rich systems performance.

PubMed

Bushko, Renata G

2005-01-01

The universe is non repeatable in nature--most of events cannot be prestated and do not repeat themselves. The only way to create systems that are truly useful is to make them adaptive (able to reason by analogy and learn) and rich in knowledge (including common sense knowledge). Adaptive and knowledge-rich health management could get us closer to errorless health care where small incremental adjustments happen all the time preventing occurrence of an error. In the era of adaptive systems we need to have a way to evaluate their performance. Are they truly adaptive? How adaptive are they? Are they accurate enough? Are they fast enough? Are they cost effective? This chapter presents general framework for measuring adaptive knowledge-rich systems' performance and includes among others definitions of adaptiveness factor, britt (a unit of brittleness) and uso-quant (unit of usefulness of a piece of knowledge). Measuring adaptive knowledge-rich systems performance is one of the most important research areas that can have a big pay-off in healthcare now and in the future.

Risk factors for complications in donors at first and repeat whole blood donation: a cohort study with assessment of the impact on donor return

PubMed Central

Wiersum-Osselton, Johanna C.; Marijt-van derKreek, Tanneke; Brand, Anneke; Veldhuizen, Ingrid; van der Bom, Johanna G.; de Kort, Wim

2014-01-01

Background First-time donation is among recognised risk factors for vasovagal reactions to blood donation and reactions are known to reduce donor return. We assessed associations between potential risk factors and vasovagal reactions and needle-related complications in first-time whole blood donation in comparison to repeat donation and analysed the impact of complications on donor return. Materials and methods We performed a cohort study on whole blood donations in The Netherlands from 1/1/2010 to 31/12/2010 using data extracted from the blood service information system. Donation data up to 31/12/2011 were used to ascertain donor return. Results In 2010 28,786 donors made first whole blood donations and there were 522,958 repeat donations. Vasovagal reactions occurred in 3.9% of first donations by males and 3.5% of first donations by females compared to in 0.2% and 0.6%, respectively, of repeat donations. Associations of vasovagal reactions with other factors including age, body weight, systolic and diastolic blood pressure were similar in first-time and repeat donors. Needle-related complications occurred in 0.2% of male and 0.5% of female first-time donations and in 0.1% and 0.3%, respectively, of repeat donations. Among first-time donors, the return rate within 1 year was 82% following an uncomplicated first donation, but 55% and 61% following vasovagal reactions and needle-related complications, respectively; the corresponding percentages among repeat donors were 86%, 58% and 82%. Discussion Among first-time donors, females suffered less than males from vasovagal reactions. Other risk factors had similar associations among first-time and repeat donors. Vasovagal reactions and needle-related complications in both first-time and repeat donors are followed by reduced donor return. PMID:23867173

Risks of repeated miscarriage.

PubMed

George, Lena; Granath, Fredrik; Johansson, Anna L V; Olander, Bodil; Cnattingius, Sven

2006-03-01

There is a lack of well-designed epidemiological studies of possible risk factors for repeated miscarriage. In this Swedish population-based case-control study, we investigated the association between sociodemographic and anthropometric factors, obstetric history and life-style factors, with respect to the risks of first-trimester repeated miscarriage. Information on maternal characteristics was collected through in-person interviews. Plasma blood samples were analysed for cotinine and folate concentrations. Adjusted odds ratios (OR) with 95% confidence interval [CI] were used to estimate the relative risk of repeated miscarriage. The risks of repeated miscarriage were increased for women aged > or = 35 years (adjusted OR 2.9 [95% CI 1.4, 5.8]), as well as for women aged < or = 24 years (OR 2.8 [95% CI 1.1, 6.8]). Women with a history of at least one preceding miscarriage prior to the two index pregnancies, women reporting prolonged time to conceive, and women with a history of myoma, faced a more than fourfold increased risk of repeated miscarriage. Smokers were at an increased risk of repeated miscarriage (OR 2.1 [95% CI 1.1, 4.1]). Among non-smoking women with high caffeine intake, there was an increased risk of repeated miscarriage, whereas there was no such association among smokers. Low plasma folate levels were not associated with increased risks.

Alcohol warnings in TV beer advertisements.

PubMed

Slater, M D; Domenech, M M

1995-05-01

Mandated warnings are among the few steps Congress has taken to influence the use of legal substances such as alcohol. The usefulness of such warnings in discouraging abuse of alcohol is, however, controversial. This study examines the impact of televised warnings on probable antecedents of belief change not examined in previous research: confidence in beliefs about beer risks or benefits, and cognitive responses to the advertisements. The present study (N = 75 male and female college students) tests four of the warnings recommended in Senate Bill 674 (1993--the "Thurmond bill") edited into randomly sampled television beer advertisements, using a between-subjects treatment-and-control experimental design. The four advertisements or advertisement/warning pairs were counterbalanced and analyzed as a repeated measures factor. The study indicated, as hypothesized, that subjects exposed to warnings tended to have less confidence in their generally skeptical assessments of beer risks--a likely precursor to belief change in resistant populations. Repeated exposure to the advertisements alone also appeared to lead to increased confidence in generally positive assessments of beer benefits, whereas repeated exposure to warnings led to decreased confidence in such assessments. Repeated exposure to warnings also may have primed negative reactions to subsequent beer advertisements. These results suggest mechanisms by which alcohol warnings may over time influence beliefs. Measures used here may serve as useful criterion variables in future studies on warnings. Further attention to optimizing warning content and presentation is recommended.

Demonstration of repeatability in a high-energy-density planar shear mixing layer experiment

DOE PAGES

Merritt, Elizabeth Catherine; Doss, Forrest William; Di Stefano, Carlos A.; ...

2017-03-11

On laser-driven platforms the assumption of experiment repeatability is particularly important due to a typically low data acquisition rate that doesn’t often allow for data redundancy. If the platform is repeatable, then measurements of the repeatable dynamics from multiple experiments can be treated as measurements of the same system. In high-energy-density hydrodynamic instability experiments the interface growth is assumed to be one of the repeatable aspects of the system. In this paper we demonstrate the repeatability of the instability growth in the counter-propagating shear experiment at the OMEGA laser facility, where the instability growth is characterized by the tracer layermore » thickness or mix-width evolution. Furthermore, in our previous experiment campaigns we have assumed the instability growth was repeatable enough to identify trends, but in this work we explicitly show that the mix-width measurements for nominally identical experiments are repeatable within the measurement error bars.« less

Dyslipidemia patterns are differentially associated with dietary factors.

PubMed

Song, SuJin; Paik, Hee Young; Park, Minseon; Song, YoonJu

2016-08-01

Dyslipidemia, a strong predictor of cardiovascular diseases, is prevalent among Korean adults, but little is known about the associations between overall lipid profiles and dietary factors. We identified dyslipidemia patterns among lipid indicators and examined dietary factors associated with dyslipidemia patterns in Korean adults. Subjects in this cross-sectional study were recruited from the Family Medicine Division or the Health Examination Center of the general hospital in Seoul between 2010 and 2012. Measurements of biochemical and dietary variables repeated three times were collected from a total of 138 subjects at 3- to 4-month intervals when the subjects visited the hospital. Dietary intake data were obtained using 24-h recalls. In order to estimate typical values for biochemical and dietary variables, the averages of repeated measures for each subject were calculated. To identify dyslipidemia patterns, factor analysis was used based on total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), triglycerides (TG), and high-density lipoprotein cholesterol (HDLC). Two dyslipidemia patterns, (1) TC & LDLC and (2) TG & HDLC, were identified. Dietary fat and cholesterol intakes were positively associated with the TC & LDLC pattern score, but not associated with the TG & HDLC pattern score. The TG & HDLC pattern was significantly associated with low intakes of calcium, potassium, milk and dairy products. Two dyslipidemia patterns were associated with dietary factors in Korean adults. Further studies should investigate specific dietary recommendations according to lipid profiles in the prevention and management of dyslipidemia in Korea. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Some anemonefish lack personality: a comparative assessment of behavioral variation and repeatability in relation to environmental and social factors

NASA Astrophysics Data System (ADS)

Wong, Marian Y. L.; Beasley, Amanda L.; Douglass, Tasman; Whalan, Steve; Scott, Anna

2017-12-01

Determining the extent of repeatable differences in the behavior of animals and the factors that influence behavioral expression is important for understanding individual fitness and population processes, thereby aiding in species conservation. However, little is known about the causes of variation in the repeatability of behavioral differences among species because rarely have comparative studies been undertaken to examine the repeatability of behavioral differences among individuals within their natural ecological settings. Using two species of endemic subtropical anemonefishes, Amphiprion mccullochi and A. latezonatus at Lord Howe and North Solitary Islands, Australia, we conducted an in situ comparative analysis of personality traits, examining the repeatability of boldness, sociability and aggression as well as the potential role of environmental and social factors on behavioral expression. For A. mccullochi, only boldness and aggression were highly repeatable and these behaviors formed a behavioral syndrome. For A. latezonatus, none of the three behaviors were repeatable due to low-inter-individual variation in behavior. We suggest that the harsher and more variable environmental and social conditions experienced by A. latezonatus have resulted in reduced repeatability in behavior, in contrast to A. mccullochi which typically inhabits a more stable lagoonal reef environment. Additionally, group size and size rank, rather than nearest-neighbor distance and anemone size, influenced the expression of these behaviors in both species, suggesting that behavioral variation was more sensitive to social than environmental factors. Overall, differences in repeatability between these closely related species likely reflect adaptations to contrasting environmental and social conditions, although alternative explanations must be considered. The differences in behavioral consistency between these two endemic anemonefishes could lead to disparity in their resilience to environmental or social change in the future.

Genetic variants in IGF-I, IGF-II, IGFBP-3, and adiponectin genes and colon cancer risk in African Americans and Whites

PubMed Central

Keku, Temitope O.; Vidal, Adriana; Oliver, Shannon; Hoyo, Catherine; Hall, Ingrid J.; Omofoye, Seun; McDoom, Maya; Worley, Kendra; Galanko, Joseph; Sandler, Robert S.; Millikan, Robert

2014-01-01

Purpose Evaluating genetic susceptibility may clarify effects of known environmental factors and also identify individuals at high risk. We evaluated the association of four insulin-related pathway gene polymorphisms in insulin-like growth factor-1 (IGF-I) (CA)n repeat, insulin-like growth factor-2 (IGF-II) (rs680), insulin-like growth factor binding protein-3 (IGFBP-3) (rs2854744), and adiponectin (APM1 rs1501299) with colon cancer risk, as well as relationships with circulating IGF-I, IGF-II, IGFBP-3, and C-peptide in a population-based study. Methods Participants were African Americans (231cases, 306 controls) and Whites (297 cases, 530 controls). Consenting subjects provided blood specimens, and lifestyle/diet information. Genotyping for all genes except IGF-I was performed by the 5′-exonuclease (Taqman) assay. The IGF-I (CA)n repeat was assayed by PCR, and fragment analysis. Circulating proteins were measured by enzyme immunoassays. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression. Results The IGF-I (CA)19 repeat was higher in White controls (50%) than African American controls (31%). Whites homozygous for the IGF-I (CA)19 repeat had a nearly two fold increase in risk of colon cancer (OR=1.77; 95%CI=1.15–2.73), but not African Americans (OR= 0.73, 95%CI 0.50–1.51). We observed an inverse association between the IGF-II Apa1 A-variant and colon cancer risk (OR= 0.49, 95%CI 0.28–0.88) in Whites only. Carrying the IGFBP-3 variant alleles was associated with lower IGFBP-3 protein levels, a difference most pronounced in Whites (p- trend < 0.05). Conclusions These results support an association between insulin pathway-related genes and elevated colon cancer risk in Whites but not in African Americans. PMID:22565227

Genetic variants in IGF-I, IGF-II, IGFBP-3, and adiponectin genes and colon cancer risk in African Americans and Whites.

PubMed

Keku, Temitope O; Vidal, Adriana; Oliver, Shannon; Hoyo, Catherine; Hall, Ingrid J; Omofoye, Oluwaseun; McDoom, Maya; Worley, Kendra; Galanko, Joseph; Sandler, Robert S; Millikan, Robert

2012-07-01

Evaluating genetic susceptibility may clarify effects of known environmental factors and also identify individuals at high risk. We evaluated the association of four insulin-related pathway gene polymorphisms in insulin-like growth factor-1 (IGF-I) (CA)( n ) repeat, insulin-like growth factor-2 (IGF-II) (rs680), insulin-like growth factor-binding protein-3 (IGFBP-3) (rs2854744), and adiponectin (APM1 rs1501299) with colon cancer risk, as well as relationships with circulating IGF-I, IGF-II, IGFBP-3, and C-peptide in a population-based study. Participants were African Americans (231 cases and 306 controls) and Whites (297 cases, 530 controls). Consenting subjects provided blood specimens and lifestyle/diet information. Genotyping for all genes except IGF-I was performed by the 5'-exonuclease (Taqman) assay. The IGF-I (CA)(n) repeat was assayed by PCR and fragment analysis. Circulating proteins were measured by enzyme immunoassays. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated by logistic regression. The IGF-I (CA)( 19 ) repeat was higher in White controls (50 %) than African American controls (31 %). Whites homozygous for the IGF-I (CA)(19) repeat had a nearly twofold increase in risk of colon cancer (OR = 1.77; 95 % CI = 1.15-2.73), but not African Americans (OR = 0.73, 95 % CI 0.50-1.51). We observed an inverse association between the IGF-II Apa1 A-variant and colon cancer risk (OR = 0.49, 95 % CI 0.28-0.88) in Whites only. Carrying the IGFBP-3 variant alleles was associated with lower IGFBP-3 protein levels, a difference most pronounced in Whites (p-trend <0.05). These results support an association between insulin pathway-related genes and elevated colon cancer risk in Whites but not in African Americans.

Safety compliance and safety climate: A repeated cross-sectional study in the oil and gas industry.

PubMed

Kvalheim, Sverre A; Dahl, Øyvind

2016-12-01

Violations of safety rules and procedures are commonly identified as a causal factor in accidents in the oil and gas industry. Extensive knowledge on effective management practices related to improved compliance with safety procedures is therefore needed. Previous studies of the causal relationship between safety climate and safety compliance demonstrate that the propensity to act in accordance with prevailing rules and procedures is influenced to a large degree by workers' safety climate. Commonly, the climate measures employed differ from one study to another and identical measures of safety climate are seldom tested repeatedly over extended periods of time. This research gap is addressed in the present study. The study is based on a survey conducted four times among sharp-end workers of the Norwegian oil and gas industry (N=31,350). This is done by performing multiple tests (regression analysis) over a period of 7years of the causal relationship between safety climate and safety compliance. The safety climate measure employed is identical across the 7-year period. Taking all periods together, the employed safety climate model explained roughly 27% of the variance in safety compliance. The causal relationship was found to be stable across the period, thereby increasing the reliability and the predictive validity of the factor structure. The safety climate factor that had the most powerful effect on safety compliance was work pressure. The factor structure employed shows high predictive validity and should therefore be relevant to organizations seeking to improve safety in the petroleum sector. The findings should also be relevant to other high-hazard industries where safety rules and procedures constitute a central part of the approach to managing safety. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.

Cryo-scatter measurements of beryllium

NASA Astrophysics Data System (ADS)

Lippey, Barret; Krone-Schmidt, Wilfried

1991-12-01

Bi-directional Reflection Distribution Function measurements were performed as a function of cryogenic temperature for various substrates. Substrates investigated include HIPed and sputtered beryllium produced from different powders and by various manufacturing and polishing processes. In some samples investigated, the BRDF at 10.6 microns increased by a factor of 2 to 5 during cooling from 300 to 30 Kelvin. On repeated temperature cycling the change in BRDF appeared to be totally elastic. The cryo-scatter effect does not occur for all types of beryllium.

Power analysis for multivariate and repeated measurements designs via SPSS: correction and extension of D'Amico, Neilands, and Zambarano (2001).

PubMed

Osborne, Jason W

2006-05-01

D'Amico, Neilands, and Zambarano (2001) published SPSS syntax to perform power analyses for three complex procedures: ANCOVA, MANOVA, and repeated measures ANOVA. Unfortunately, the published SPSS syntax for performing the repeated measures analysis needed some minor revision in order to perform the analysis correctly. This article presents the corrected syntax that will successfully perform the repeated measures analysis and provides some guidance on modifying the syntax to customize the analysis.

Psychiatric Hospitalization after Emergency Treatment for Deliberate Self-Harm is Associated with Repeated Deliberate Self-Harm.

PubMed

Ichimura, Atshushi; Kato, Koji; Taira, Takayuki; Otsuka, Hiroyuki; Seki, Tomoko; Nakagawa, Yoshihide; Inokuchi, Sadaki

2018-02-23

To evaluate whether treatment at a psychiatric hospital reduces the risk of repeating parasuicide. Participants comprised 4,483 parasuicide patients admitted to an emergency department between July 2003 and March 2012. We analyzed the effectiveness of psychiatric hospitalization in preventing repeated parasuicide. We adjusted for background factors using multivariate logistic regression. Effects of psychiatric hospitalization upon the likelihood of repeated parasuicide within one year varied by age (especially those aged <35 years), indicating that hospitalization was a significant risk factor. We must be mindful of the risk of repeated parasuicide following discharge in young patients and to provide them with ongoing outpatient care and multimodal support.

Precision and repeatability of the Optotrak 3020 motion measurement system.

PubMed

States, R A; Pappas, E

2006-01-01

Several motion analysis systems are used by researchers to quantify human motion and to perform accurate surgical procedures. The Optotrak 3020 is one of these systems and despite its widespread use there is not any published information on its precision and repeatability. We used a repeated measures design study to evaluate the precision and repeatability of the Optotrak 3020 by measuring distance and angle in three sessions, four distances and three conditions (motion, static vertical, and static tilted). Precision and repeatability were found to be excellent for both angle and distance although they decreased with increasing distance from the sensors and with tilt from the plane of the sensors. Motion did not have a significant effect on the precision of the measurements. In conclusion, the measurement error of the Optotrak is minimal. Further studies are needed to evaluate its precision and repeatability under human motion conditions.

The development and reliability of a repeated anaerobic cycling test in female ice hockey players.

PubMed

Wilson, Kier; Snydmiller, Gary; Game, Alex; Quinney, Art; Bell, Gordon

2010-02-01

The purpose of this study was to develop and assess the reliability of a repeated anaerobic power cycling test designed to mimic the repeated sprinting nature of the sport of ice hockey. Nineteen female varsity ice hockey players (mean X +/- SD age, height and body mass = 21 +/- 2 yr, 166.6 +/- 6.3 cm and 62.3 +/- 7.3) completed 3 trials of a repeated anaerobic power test on a Monark cycle ergometer on different days. The test consisted of "all-out" cycling for 5 seconds separated by 10 seconds of low-intensity cycling, repeated 4 times. The relative load factor used for the resistance setting was equal to 0.095 kg per kilogram body mass. There was no significant difference between the peak 5-second power output (PO), mean PO, or the fatigue index (%) among the 3 different trials. The peak 5-second PO was 702.6 +/- 114.8 w and 11.3 +/- 1.1 w x kg, whereas the mean PO across the 4 repeats was 647.1 +/- 96.3 w and 10.4 +/- 1.0 w x kg averaged for the 3 different tests. The fatigue index averaged 17.8 +/- 6.5%. The intraclass correlation coefficient for peak 5-second, mean PO, and fatigue index was 0.82, 0.86, and 0.82, respectively. This study reports the methodology of a repeated anaerobic power cycling test that was reliable for the measurement of PO and calculated fatigue index in varsity women ice hockey players and can be used as a laboratory-based assessment of repeated anaerobic fitness.

Repeatability, Reproducibility, Separative Power and Subjectivity of Different Fish Morphometric Analysis Methods

PubMed Central

Takács, Péter

2016-01-01

We compared the repeatability, reproducibility (intra- and inter-measurer similarity), separative power and subjectivity (measurer effect on results) of four morphometric methods frequently used in ichthyological research, the “traditional” caliper-based (TRA) and truss-network (TRU) distance methods and two geometric methods that compare landmark coordinates on the body (GMB) and scales (GMS). In each case, measurements were performed three times by three measurers on the same specimen of three common cyprinid species (roach Rutilus rutilus (Linnaeus, 1758), bleak Alburnus alburnus (Linnaeus, 1758) and Prussian carp Carassius gibelio (Bloch, 1782)) collected from three closely-situated sites in the Lake Balaton catchment (Hungary) in 2014. TRA measurements were made on conserved specimens using a digital caliper, while TRU, GMB and GMS measurements were undertaken on digital images of the bodies and scales. In most cases, intra-measurer repeatability was similar. While all four methods were able to differentiate the source populations, significant differences were observed in their repeatability, reproducibility and subjectivity. GMB displayed highest overall repeatability and reproducibility and was least burdened by measurer effect. While GMS showed similar repeatability to GMB when fish scales had a characteristic shape, it showed significantly lower reproducability (compared with its repeatability) for each species than the other methods. TRU showed similar repeatability as the GMS. TRA was the least applicable method as measurements were obtained from the fish itself, resulting in poor repeatability and reproducibility. Although all four methods showed some degree of subjectivity, TRA was the only method where population-level detachment was entirely overwritten by measurer effect. Based on these results, we recommend a) avoidance of aggregating different measurer’s datasets when using TRA and GMS methods; and b) use of image-based methods for morphometric surveys. Automation of the morphometric workflow would also reduce any measurer effect and eliminate measurement and data-input errors. PMID:27327896

The Psychometric Evaluation of the Connor-Davidson Resilience Scale Using a Chinese Military Sample

PubMed Central

Xie, Yuanjun; Peng, Li; Zuo, Xin; Li, Min

2016-01-01

This study examined the psychometric properties of the Connor-Davidson Resilience Scale (CD-RISC) with a Chinese military population with the aim of finding a suitable instrument to quantify resilience in Chinese military service members. The confirmatory factor analysis results did not support the factorial structure of the original or the Chinese community version of the CD-RISC, but the exploratory factor analysis results revealed a three-factor model (composed of Competency, Toughness, and Adaptability) that seemed to fit. Moreover, the repeat confirmatory factory analysis replicated the three-factor model. Additionally, the CD-RISC with a Chinese military sample exhibited appropriate psychometric properties, including internal consistency, test-retest reliability, and structural and concurrent validity. The revised CD-RISC with a Chinese military sample provides insight into the resilience measurement framework and could be a reliable and valid measurement for evaluating resilience in a Chinese military population. PMID:26859484

Resilience following spinal cord injury: A prospective controlled study investigating the influence of the provision of group cognitive behavior therapy during inpatient rehabilitation.

PubMed

Guest, Rebecca; Craig, Ashley; Nicholson Perry, Kathryn; Tran, Yvonne; Ephraums, Catherine; Hales, Alison; Dezarnaulds, Annalisa; Crino, Rocco; Middleton, James

2015-11-01

To examine change in resilience in people with spinal cord injury (SCI) when group cognitive behavior therapy (GCBT) was added to routine psychosocial rehabilitation (RPR). A prospective repeated-measures cohort design was used to determine the efficacy of the addition of GCBT (n = 50). The control group consisted of individuals receiving RPR, which included access to individual CBT (ICBT) when required (n = 38). Groups were assessed on 3 occasions: soon after admission, within 2 weeks of discharge, and 6-months postdischarge. Measures included sociodemographic, injury, and psychosocial factors. The outcome variable was resilience, considered an important outcome measure for recovery. To adjust for baseline differences in self-efficacy, depressive mood and anxiety between the 2 groups, these factors were entered into a repeated measures multivariate analysis of covariance (MANCOVA) as covariates. Latent class analysis was used to determine the best-fitting model of resilience trajectories for both groups. The MANCOVA indicated that the addition of GCBT to psychosocial rehabilitation did not result in improved resilience compared with the ICBT group. Trajectory data indicated over 60% were demonstrating acceptable resilience irrespective of group. Changes in resilience mean scores suggest the addition of GCBT adds little to resilience outcomes. Latent class modeling indicated both groups experienced similar trajectories of improvement and deterioration. Results highlight the importance of conducting multivariate modeling analysis that isolates subgroups of related cases over time to understand complex trajectories. Further research is needed to clarify individual differences in CBT intervention preference as well as other factors which impact on resilience. (c) 2015 APA, all rights reserved).

Effects of Task-Specific Augmented Feedback on Deficit Modification During Performance of the Tuck-Jump Exercise

PubMed Central

Stroube, Benjamin W.; Myer, Gregory D.; Brent, Jensen L.; Ford, Kevin R.; Heidt, Robert S.; Hewett, Timothy E.

2014-01-01

Context Anterior cruciate ligament (ACL) injuries are prevalent in female athletes. Specific factors have possible links to increasing a female athlete’s chances of suffering an ACL injury. However, it is unclear if augmented feedback may be able to decrease possible risk factors. Objective To compare the effects of task-Specific feedback on a repeated tuck-jump maneuver. Design Double-blind randomized controlled trial. Setting Sports-medicine biodynamics center. Patients 37 female subjects (14.7 ± 1.5 y, 160.9 ± 6.8 cm, 54.5 ± 7.2 kg). Intervention All athletes received standard off-season training consisting of strength training, plyometrics, and conditioning. They were also videotaped during each session while running on a treadmill at a standardized speed (8 miles/h) and while performing a repeated tuck-jump maneuver for 10 s. The augmented feedback group (AF) received feedback on deficiencies present in a 10-s tuck jump, while the control group (CTRL) received feedback on 10-s treadmill running. Main Outcome Measures Outcome measurements of tuck-jump deficits were scored by a blinded rater to determine the effects of group (CTRL vs AF) and time (pre- vs posttesting) on changes in measured deficits. Results A significant interaction of time by group was noted with the task-Specific feedback training (P = .03). The AF group reduced deficits measured during the tuck-jump assessment by 23.6%, while the CTRL training reduced deficits by 10.6%. Conclusions The results of the current study indicate that task-Specific feedback is effective for reducing biomechanical risk factors associated with ACL injury. The data also indicate that Specific components of the tuck-jump assessment are potentially more modifiable than others. PMID:23238301

Measuring lifetime stress exposure and protective factors in life course research on racial inequality and birth outcomes.

PubMed

Malat, Jennifer; Jacquez, Farrah; Slavich, George M

2017-07-01

There has been a long-standing interest in better understanding how social factors contribute to racial disparities in health, including birth outcomes. A recent emphasis in this context has been on identifying the effects of stress exposure and protective factors experienced over the entire lifetime. Yet despite repeated calls for a life course approach to research on this topic, very few studies have actually assessed how stressors and protective factors occurring over women's lives relate to birth outcomes. We discuss this issue here by describing how challenges in the measurement of lifetime stress exposure and protective factors have prevented researchers from developing an empirically-based life course perspective on health. First, we summarize prevailing views on racial inequality and birth outcomes; second, we discuss measurement challenges that exist in this context; and finally, we describe both new tools and needed tools for assessing lifetime stress exposure and suggest opportunities for integrating information on stress exposure and psychosocial protective factors. We conclude that more studies are needed that integrate information about lifetime stress exposures and the protective factors that promote resilience against such exposures to inform policy and practice recommendations to reduce racial disparities in birth outcomes.

Determination of vertebral range of motion using inertial measurement units in 27 Franches-Montagnes stallions and comparison between conditions and with a mixed population.

PubMed

Heim, C; Pfau, T; Gerber, V; Schweizer, C; Doherr, M; Schüpbach-Regula, G; Witte, S

2016-07-01

The diagnosis of equine back disorders is challenging. Objectively determining movement of the vertebral column may therefore be of value in a clinical setting. To establish whether surface-mounted inertial measurement units (IMUs) can be used to establish normal values for range of motion (ROM) of the vertebral column in a uniform population of horses trotting under different conditions. Vertebral ROM was established in Franches-Montagnes stallions and a general population of horses and the variability in measurements compared between the two groups. Repeatability and the influence of specific exercise condition (on ROM) were assessed. Finally, attempts were made to explain the findings of the study through the evaluation of factors that might influence ROM. Dorsoventral (DV) and mediolateral (ML) vertebral ROM was measured at a trot under different exercise conditions in 27 Franches-Montagnes stallions and six general population horses using IMUs distributed over the vertebral column. Variability in the ROM measurements was significantly higher for general population horses than for Franches-Montagnes stallions (both DV and ML ROM). Repeatability was strong to very strong for DV measurements and moderate for ML measurements. Trotting under saddle significantly reduced the ROM, with sitting trot resulting in a significantly lower ROM than rising trot. Age is unlikely to explain the low variability in vertebral ROM recorded in the Franches-Montagnes horses, while this may be associated with conformational factors. It was possible to establish a normal vertebral ROM for a group of Franches-Montagnes stallions. While within-breed variation was low in this population, further studies are necessary to determine variation in vertebral ROM for other breeds and to assess their utility for diagnosis of equine back disorders. © 2015 EVJ Ltd.

Carpal tunnel syndrome: the role of occupational factors.

PubMed

Palmer, Keith T

2011-02-01

Carpal tunnel syndrome (CTS) is a fairly common condition in working-aged people, sometimes caused by physical occupational activities, such as repeated and forceful movements of the hand and wrist or use of hand-held, powered, vibratory tools. Symptoms may be prevented or alleviated by primary control measures at work, and some cases of disease are compensable. Following a general description of the disorder, its epidemiology and some of the difficulties surrounding diagnosis, this review focusses on the role of occupational factors in causation of CTS and factors that can mitigate risk. Areas of uncertainty, debate and research interest are emphasised where relevant. Copyright © 2011 Elsevier Ltd. All rights reserved.

Research Spotlight: New method to assess coral reef health

NASA Astrophysics Data System (ADS)

Tretkoff, Ernie

2011-03-01

Coral reefs around the world are becoming stressed due to rising temperatures, ocean acidification, overfishing, and other factors. Measuring community level rates of photosynthesis, respiration, and biogenic calcification is essential to assessing the health of coral reef ecosystems because the balance between these processes determines the potential for reef growth and the export of carbon. Measurements of biological productivity have typically been made by tracing changes in dissolved oxygen in seawater as it passes over a reef. However, this is a labor-intensive and difficult method, requiring repeated measurements. (Geophysical Research Letters, doi:10.1029/2010GL046179, 2011)

The predictive value of markers of fibrinolysis and endothelial dysfunction in the post thrombotic syndrome. A systematic review.

PubMed

Rabinovich, Anat; Cohen, Jacqueline M; Kahn, Susan R

2014-06-01

The post thrombotic syndrome (PTS) develops in 20-40% of deep venous thrombosis (DVT) patients. Risk factors for PTS have not been well elucidated. Identification of risk factors would facilitate individualised risk assessment for PTS. We conducted a systematic review to determine whether biomarkers of fibrinolysis or endothelial dysfunction can predict the risk for PTS among DVT patients. Studies were identified by searching the electronic databases PubMed, EMBASE, Scopus and Web of science. We included studies published between 1990 and 2013, measured biomarker levels in adult DVT patients, and reported rates of PTS development. Fourteen studies were included: 11 investigated the association between D-dimer and PTS; three examined fibrinogen; two measured von Willebrand factor; one measured plasminogen activator inhibitor-1; one assessed ADAMTS-13 (A Disintegrin and Metalloprotease with Thrombospondin type 1 repeats) and one measured factor XIII activity. Studies varied with regards to inclusion criteria, definition of PTS, time point and method of biomarker measurement. We were unable to meta-analyse results due to marked clinical heterogeneity. Descriptively, a significant association with PTS was found for D-dimer in four studies and factor XIII in one study. Further prospective research is needed to elucidate whether these markers might be useful to predict PTS development.

Repeated measures from FIA data facilitates analysis across spatial scales of tree growth responses to nitrogen deposition from individual trees to whole ecoregions

Treesearch

Charles H. (Hobie) Perry; Kevin J. Horn; R. Quinn Thomas; Linda H. Pardo; Erica A.H. Smithwick; Doug Baldwin; Gregory B. Lawrence; Scott W. Bailey; Sabine Braun; Christopher M. Clark; Mark Fenn; Annika Nordin; Jennifer N. Phelan; Paul G. Schaberg; Sam St. Clair; Richard Warby; Shaun Watmough; Steven S. Perakis

2015-01-01

The abundance of temporally and spatially consistent Forest Inventory and Analysis data facilitates hierarchical/multilevel analysis to investigate factors affecting tree growth, scaling from plot-level to continental scales. Herein we use FIA tree and soil inventories in conjunction with various spatial climate and soils data to estimate species-specific responses of...

Validity and repeatability of inertial measurement units for measuring gait parameters.

PubMed

Washabaugh, Edward P; Kalyanaraman, Tarun; Adamczyk, Peter G; Claflin, Edward S; Krishnan, Chandramouli

2017-06-01

Inertial measurement units (IMUs) are small wearable sensors that have tremendous potential to be applied to clinical gait analysis. They allow objective evaluation of gait and movement disorders outside the clinic and research laboratory, and permit evaluation on large numbers of steps. However, repeatability and validity data of these systems are sparse for gait metrics. The purpose of this study was to determine the validity and between-day repeatability of spatiotemporal metrics (gait speed, stance percent, swing percent, gait cycle time, stride length, cadence, and step duration) as measured with the APDM Opal IMUs and Mobility Lab system. We collected data on 39 healthy subjects. Subjects were tested over two days while walking on a standard treadmill, split-belt treadmill, or overground, with IMUs placed in two locations: both feet and both ankles. The spatiotemporal measurements taken with the IMU system were validated against data from an instrumented treadmill, or using standard clinical procedures. Repeatability and minimally detectable change (MDC) of the system was calculated between days. IMUs displayed high to moderate validity when measuring most of the gait metrics tested. Additionally, these measurements appear to be repeatable when used on the treadmill and overground. The foot configuration of the IMUs appeared to better measure gait parameters; however, both the foot and ankle configurations demonstrated good repeatability. In conclusion, the IMU system in this study appears to be both accurate and repeatable for measuring spatiotemporal gait parameters in healthy young adults. Copyright © 2017 Elsevier B.V. All rights reserved.

A Genome-Wide Association Study Identifies a Novel Major Locus for Glycemic Control in Type 1 Diabetes, as Measured by Both A1C and Glucose

PubMed Central

Paterson, Andrew D.; Waggott, Daryl; Boright, Andrew P.; Hosseini, S. Mohsen; Shen, Enqing; Sylvestre, Marie-Pierre; Wong, Isidro; Bharaj, Bhupinder; Cleary, Patricia A.; Lachin, John M.; Below, Jennifer E.; Nicolae, Dan; Cox, Nancy J.; Canty, Angelo J.; Sun, Lei; Bull, Shelley B.

2010-01-01

OBJECTIVE Glycemia is a major risk factor for the development of long-term complications in type 1 diabetes; however, no specific genetic loci have been identified for glycemic control in individuals with type 1 diabetes. To identify such loci in type 1 diabetes, we analyzed longitudinal repeated measures of A1C from the Diabetes Control and Complications Trial. RESEARCH DESIGN AND METHODS We performed a genome-wide association study using the mean of quarterly A1C values measured over 6.5 years, separately in the conventional (n = 667) and intensive (n = 637) treatment groups of the DCCT. At loci of interest, linear mixed models were used to take advantage of all the repeated measures. We then assessed the association of these loci with capillary glucose and repeated measures of multiple complications of diabetes. RESULTS We identified a major locus for A1C levels in the conventional treatment group near SORCS1 (10q25.1, P = 7 × 10−10), which was also associated with mean glucose (P = 2 × 10−5). This was confirmed using A1C in the intensive treatment group (P = 0.01). Other loci achieved evidence close to genome-wide significance: 14q32.13 (GSC) and 9p22 (BNC2) in the combined treatment groups and 15q21.3 (WDR72) in the intensive group. Further, these loci gave evidence for association with diabetic complications, specifically SORCS1 with hypoglycemia and BNC2 with renal and retinal complications. We replicated the SORCS1 association in Genetics of Diabetes in Kidneys (GoKinD) study control subjects (P = 0.01) and the BNC2 association with A1C in nondiabetic individuals. CONCLUSIONS A major locus for A1C and glucose in individuals with diabetes is near SORCS1. This may influence the design and analysis of genetic studies attempting to identify risk factors for long-term diabetic complications. PMID:19875614

Dynamic properties of a dirt and a synthetic equine racetrack surface measured by a track-testing device.

PubMed

Setterbo, J J; Fyhrie, P B; Hubbard, M; Upadhyaya, S K; Stover, S M

2013-01-01

Racetrack surface is a risk factor for Thoroughbred racehorse injury and death that can be engineered and managed. To investigate the relationship between surface and injury, the mechanical behaviour of dirt and synthetic track surfaces must be quantified. To compare dynamic properties of a dirt and a synthetic surface in situ using a track-testing device designed to simulate equine hoof impact; and to determine the effects of impact velocity, impact angle and repeated impact on dynamic surface behaviour. A track-testing device measured force and displacement during impact into a dirt and a synthetic surface at 3 impact velocities (1.91, 2.30, 2.63 m/s), 2 impact angles (0°, 20° from vertical), and 2 consecutive impacts (initial, repeat). Surfaces were measured at 3 locations/day for 3 days. The effects of surface type, impact velocity, impact angle and impact number on dynamic surface properties were assessed using analysis of variance. Synthetic surface maximum forces, load rates and stiffnesses were 37-67% of dirt surface values. Surfaces were less stiff with lower impact velocities, angled impacts and initial impacts. The magnitude of differences between dirt and synthetic surfaces increased for repeat impacts and higher impact velocities. The synthetic surface was generally softer than the dirt surface. Greatly increased hardness for repeat impacts corroborates the importance of maintenance. Results at different impact velocities suggest that surface differences will persist at higher impact velocities. For both surfaces it is clearly important to prevent horse exposure to precompacted surfaces, particularly during high-speed training when the surface has already been trampled. These data should be useful in coordinating racetrack surface management with racehorse training to prevent injuries. © 2012 EVJ Ltd.

Subglottic injury, gastric juice, corticosteroids, and peptide growth factors in a porcine model.

PubMed

Yellon, R F; Szeremeta, W; Grandis, J R; Diguisseppe, P; Dickman, P S

1998-06-01

To study the effects of mucosal injury, gastric juice, and corticosteroids and to determine the presence of peptide growth factors in the subglottic mucosa in a porcine model. Prospective cohort animal study. In this model of subglottic injury, five groups (n = 5 each) of piglets were used. Injury was induced by electrocautery (acute), electrocautery plus repeated saline application (chronic), electrocautery plus repeated gastric juice application (chronic plus gastric juice), or repeated gastric juice application (gastric). Control piglets had normal saline applied repeatedly. Histopathologic findings for the gastric juice group included basal cell hyperplasia (80%), squamous metaplasia (80%), and mucosal ulceration (40%). Control piglets showed squamous metaplasia (80%) but no basilar hyperplasia or ulceration. Immunohistochemistry detected peptide growth factors and epidermal growth factor receptor (EGFR) in all groups. Decreased staining was most frequent in the acute injury group. Quantitative reverse transcriptase polymerase chain reaction (RT-PCR) documented lower expression of EGFR in the gastric juice group (P = .01). These findings suggest that peptide growth factors and EGFR are part of normal subglottic mucosal turnover. Noxious stimuli decrease production of these factors. Gastric juice had adverse effects documented by histopathology and molecular techniques.

Repeatability of DTI-based skeletal muscle fiber tracking

PubMed Central

Heemskerk, Anneriet M.; Sinha, Tuhin K.; Wilson, Kevin J.; Ding, Zhaohua; Damon, Bruce M.

2015-01-01

Diffusion tensor imaging (DTI)-based muscle fiber tracking enables the measurement of muscle architectural parameters, such as pennation angle (θ) and fiber tract length (Lft), throughout the entire muscle. Little is known, however, about the repeatability of either the muscle architectural measures or the underlying diffusion measures. Therefore, the goal of this study was to investigate the repeatability of DTI fiber tracking-based measurements and θ and Lft. Four DTI acquisitions were performed on two days that allowed for between acquisition, within day, and between day analyses. The eigenvalues and fractional anisotropy were calculated at the maximum cross-sectional area of, and fiber tracking was performed in, the tibialis anterior muscle of nine healthy subjects. The between acquisitions condition had the highest repeatability for the DTI indices and the architectural parameters. The overall inter class correlation coefficients (ICC’s) were greater than 0.6 for both θ and Lft and the repeatability coefficients were θ <10.2° and Lft < 50 mm. In conclusion, under the experimental and data analysis conditions used, the repeatability of the diffusion measures is very good and repeatability of the architectural measurements is acceptable. Therefore, this study demonstrates the feasibility for longitudinal studies of alterations in muscle architecture using DTI-based fiber tracking, under similar noise conditions and with similar diffusion characteristics. PMID:20099372

Effect of repeat copy number on variable-number tandem repeat mutations in Escherichia coli O157:H7.

PubMed

Vogler, Amy J; Keys, Christine; Nemoto, Yoshimi; Colman, Rebecca E; Jay, Zack; Keim, Paul

2006-06-01

Variable-number tandem repeat (VNTR) loci have shown a remarkable ability to discriminate among isolates of the recently emerged clonal pathogen Escherichia coli O157:H7, making them a very useful molecular epidemiological tool. However, little is known about the rates at which these sequences mutate, the factors that affect mutation rates, or the mechanisms by which mutations occur at these loci. Here, we measure mutation rates for 28 VNTR loci and investigate the effects of repeat copy number and mismatch repair on mutation rate using in vitro-generated populations for 10 E. coli O157:H7 strains. We find single-locus rates as high as 7.0 x 10(-4) mutations/generation and a combined 28-locus rate of 6.4 x 10(-4) mutations/generation. We observed single- and multirepeat mutations that were consistent with a slipped-strand mispairing mutation model, as well as a smaller number of large repeat copy number mutations that were consistent with recombination-mediated events. Repeat copy number within an array was strongly correlated with mutation rate both at the most mutable locus, O157-10 (r2= 0.565, P = 0.0196), and across all mutating loci. The combined locus model was significant whether locus O157-10 was included (r2= 0.833, P < 0.0001) or excluded (r2= 0.452, P < 0.0001) from the analysis. Deficient mismatch repair did not affect mutation rate at any of the 28 VNTRs with repeat unit sizes of >5 bp, although a poly(G) homomeric tract was destabilized in the mutS strain. Finally, we describe a general model for VNTR mutations that encompasses insertions and deletions, single- and multiple-repeat mutations, and their relative frequencies based upon our empirical mutation rate data.

Oscillometric blood pressure devices and simulators: measurements of repeatability and differences between models.

PubMed

Sims, A J; Reay, C A; Bousfield, D R; Menes, J A; Murray, A

2005-01-01

To measure the repeatability and pressure pulse envelope of simulators used for testing oscillometric non-invasive blood pressure (NIBP) devices; to study the effect of different envelopes on NIBP devices, and to measure the difference between NIBP devices due to different oscillometric algorithms. Three different models of NIBP simulator and 18 different patient monitors with NIBP function were studied. We developed a pressure measurement system (accuracy 0.048?mmHg) to measure the repeatability of simulators. The effect of changing the envelope was measured by using three simulators with one NIBP device. Differences between 18 NIBP devices were measured using one simulator at seven blood pressure settings. Simulators generate repeatable pressure pulse envelopes (< 0.2 mmHg) but the magnitude and shape depends on the model of simulator. Oscillometric NIBP devices are highly repeatable (< 2 mmHg) when presented with a repeatable pressure pulse envelope, but different devices employ different algorithms and give different results. For a simulated standard blood pressure setting of 120/80 mmHg, estimates of systolic pressure ranged from 112.6 to 126.6 mmHg (sd of 3.0 mmHg), and diastolic pressure ranged from 74.8 to 86.9 mmHg (sd of 3.5 mmHg). Simulators and NIBP devices are sufficiently repeatable for clinical use, but further systematic clinical studies are required to better characterize the pressure pulse envelope for different patient groups.

A MEMS Electrochemical Bellows Actuator for Fluid Metering Applications

PubMed Central

Sheybani, Roya; Gensler, Heidi; Meng, Ellis

2013-01-01

We present a high efficiency wireless MEMS electrochemical bellows actuator capable of rapid and repeatable delivery of boluses for fluid metering and drug delivery applications. Nafion®-coated Pt electrodes were combined with Parylene bellows filled with DI water to form the electrolysis-based actuator. The performance of actuators with several bellows configurations was compared for a range of applied currents (1-10 mA). Up to 75 boluses were delivered with an average pumping flow rate of 114.40 ± 1.63 μL/min. Recombination of gases into water, an important factor in repeatable and reliable actuation, was studied for uncoated and Nafion®-coated actuators. Real-time pressure measurements were conducted and the effects of temperature, physiological back pressure, and drug viscosity on delivery performance were investigated. Lastly, we present wireless powering of the actuator using a class D inductive powering system that allowed for repeatable delivery with less than 2% variation in flow rate values. PMID:22833156

Automated computation of femoral angles in dogs from three-dimensional computed tomography reconstructions: Comparison with manual techniques.

PubMed

Longo, F; Nicetto, T; Banzato, T; Savio, G; Drigo, M; Meneghello, R; Concheri, G; Isola, M

2018-02-01

The aim of this ex vivo study was to test a novel three-dimensional (3D) automated computer-aided design (CAD) method (aCAD) for the computation of femoral angles in dogs from 3D reconstructions of computed tomography (CT) images. The repeatability and reproducibility of three manual radiography, manual CT reconstructions and the aCAD method for the measurement of three femoral angles were evaluated: (1) anatomical lateral distal femoral angle (aLDFA); (2) femoral neck angle (FNA); and (3) femoral torsion angle (FTA). Femoral angles of 22 femurs obtained from 16 cadavers were measured by three blinded observers. Measurements were repeated three times by each observer for each diagnostic technique. Femoral angle measurements were analysed using a mixed effects linear model for repeated measures to determine the levels of intra-observer agreement (repeatability) and inter-observer agreement (reproducibility). Repeatability and reproducibility of measurements using the aCAD method were excellent (intra-class coefficients, ICCs≥0.98) for all three angles assessed. Manual radiography and CT exhibited excellent agreement for the aLDFA measurement (ICCs≥0.90). However, FNA repeatability and reproducibility were poor (ICCs<0.8), whereas FTA measurement showed slightly higher ICCs values, except for the radiographic reproducibility, which was poor (ICCs<0.8). The computation of the 3D aCAD method provided the highest repeatability and reproducibility among the tested methodologies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determination of car on-road black carbon and particle number emission factors and comparison between mobile and stationary measurements

NASA Astrophysics Data System (ADS)

Ježek, I.; Drinovec, L.; Ferrero, L.; Carriero, M.; Močnik, G.

2015-01-01

We have used two methods for measuring emission factors (EFs) in real driving conditions on five cars in a controlled environment: the stationary method, where the investigated vehicle drives by the stationary measurement platform and the composition of the plume is measured, and the chasing method, where a mobile measurement platform drives behind the investigated vehicle. We measured EFs of black carbon and particle number concentration. The stationary method was tested for repeatability at different speeds and on a slope. The chasing method was tested on a test track and compared to the portable emission measurement system. We further developed the data processing algorithm for both methods, trying to improve consistency, determine the plume duration, limit the background influence and facilitate automatic processing of measurements. The comparison of emission factors determined by the two methods showed good agreement. EFs of a single car measured with either method have a specific distribution with a characteristic value and a long tail of super emissions. Measuring EFs at different speeds or slopes did not significantly influence the EFs of different cars; hence, we propose a new description of vehicle emissions that is not related to kinematic or engine parameters, and we rather describe the vehicle EF with a characteristic value and a super emission tail.

What can be Learned from Silage Breeding Programs?

NASA Astrophysics Data System (ADS)

Lorenz, Aaron J.; Coors, James G.

Improving the quality of cellulosic ethanol feedstocks through breeding and genetic manipulation could significantly impact the economics of this industry. Attaining this will require comprehensive and rapid characterization of large numbers of samples. There are many similarities between improving corn silage quality for dairy production and improving feedstock quality for cellulosic ethanol. It was our objective to provide insight into what is needed for genetic improvement of cellulosic feedstocks by reviewing the development and operation of a corn silage breeding program. We discuss the evolving definition of silage quality and relate what we have learned about silage quality to what is needed for measuring and improving feedstock quality. In addition, repeatability estimates of corn stover traits are reported for a set of hybrids. Repeatability of theoretical ethanol potential measured by near-infrared spectroscopy is high, suggesting that this trait may be easily improved through breeding. Just as cell wall digestibility has been factored into the latest measurements of silage quality, conversion efficiency should be standardized and included in indices of feedstock quality to maximize overall, economical energy availability.

Using portable particle sizing instrumentation to rapidly measure the penetration of fine and ultrafine particles in unoccupied residences.

PubMed

Zhao, H; Stephens, B

2017-01-01

Much of human exposure to particulate matter of outdoor origin occurs inside buildings, particularly in residences. The particle penetration factor through leaks in a building's exterior enclosure assembly is a key parameter that governs the infiltration of outdoor particles. However, experimental data for size-resolved particle penetration factors in real buildings, as well as penetration factors for fine particles less than 2.5 μm (PM 2.5 ) and ultrafine particles less than 100 nm (UFPs), remain limited, in part because of previous limitations in instrumentation and experimental methods. Here, we report on the development and application of a modified test method that utilizes portable particle sizing instrumentation to measure size-resolved infiltration factors and envelope penetration factors for 0.01-2.5 μm particles, which are then used to estimate penetration factors for integral measures of UFPs and PM 2.5 . Eleven replicate measurements were made in an unoccupied apartment unit in Chicago, IL to evaluate the accuracy and repeatability of the test procedure and solution methods. Mean estimates of size-resolved penetration factors ranged from 0.41 ± 0.14 to 0.73 ± 0.05 across the range of measured particle sizes, while mean estimates of penetration factors for integral measures of UFPs and PM 2.5 were 0.67 ± 0.05 and 0.73 ± 0.05, respectively. Average relative uncertainties for all particle sizes/classes were less than 20%. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

THICKNESS OF THE MACULA, RETINAL NERVE FIBER LAYER, AND GANGLION CELL-INNER PLEXIFORM LAYER IN THE AGE-RELATED MACULAR DEGENERATION: The Repeatability Study of Spectral Domain Optical Coherence Tomography.

PubMed

Shin, Il-Hwan; Lee, Woo-Hyuk; Lee, Jong-Joo; Jo, Young-Joon; Kim, Jung-Yeul

2018-02-01

To determine the repeatability of measuring the thickness of the central macula, retinal nerve fiber layer, and ganglion cell-inner plexiform layer (GC-IPL) using spectral domain optical coherence tomography (Cirrus HD-OCT) in eyes with age-related macular degeneration. One hundred and thirty-four eyes were included. The measurement repeatability was assessed by an experienced examiner who performed two consecutive measurements using a 512 × 128 macular cube scan and a 200 × 200 optic disk cube scan. To assess changes in macular morphology in patients with age-related macular degeneration, the patients were divided into the following three groups according to the central macular thickness (CMT): A group, CMT < 200 μm; B group, 200 μm ≤ CMT < 300 μm; and C group, CMT > 300 μm. Measurement repeatability was assessed using test-retest variability, a coefficient of variation, and an intraclass correlation coefficient. The mean measurement repeatability for the central macular, retinal nerve fiber layer, and GC-IPL thickness was high in the B group. The mean measurement repeatability for both the central macula and retinal nerve fiber layer thickness was high in the A and C groups, but was lower for the GC-IPL thickness. The measurement repeatability for GC-IPL thickness was high in the B group, but low in the A group and in the C group. The automated measurement repeatability for GC-IPL thickness was significantly lower in patients with age-related macular degeneration with out of normal CMT range. The effect of changes in macular morphology should be considered when analyzing GC-IPL thicknesses in a variety of ocular diseases.

Conservative Sample Size Determination for Repeated Measures Analysis of Covariance.

PubMed

Morgan, Timothy M; Case, L Douglas

2013-07-05

In the design of a randomized clinical trial with one pre and multiple post randomized assessments of the outcome variable, one needs to account for the repeated measures in determining the appropriate sample size. Unfortunately, one seldom has a good estimate of the variance of the outcome measure, let alone the correlations among the measurements over time. We show how sample sizes can be calculated by making conservative assumptions regarding the correlations for a variety of covariance structures. The most conservative choice for the correlation depends on the covariance structure and the number of repeated measures. In the absence of good estimates of the correlations, the sample size is often based on a two-sample t-test, making the 'ultra' conservative and unrealistic assumption that there are zero correlations between the baseline and follow-up measures while at the same time assuming there are perfect correlations between the follow-up measures. Compared to the case of taking a single measurement, substantial savings in sample size can be realized by accounting for the repeated measures, even with very conservative assumptions regarding the parameters of the assumed correlation matrix. Assuming compound symmetry, the sample size from the two-sample t-test calculation can be reduced at least 44%, 56%, and 61% for repeated measures analysis of covariance by taking 2, 3, and 4 follow-up measures, respectively. The results offer a rational basis for determining a fairly conservative, yet efficient, sample size for clinical trials with repeated measures and a baseline value.

Evaluating 1-, 2- and 3- Parameter Logistic Models Using Model-Based and Empirically-Based Simulations under Homogeneous and Heterogeneous Set Conditions

ERIC Educational Resources Information Center

Rizavi, Saba; Way, Walter D.; Lu, Ying; Pitoniak, Mary; Steffen, Manfred

2004-01-01

The purpose of this study was to use realistically simulated data to evaluate various CAT designs for use with the verbal reasoning measure of the Medical College Admissions Test (MCAT). Factors such as item pool depth, content constraints, and item formats often cause repeated adaptive administrations of an item at ability levels that are not…

Instructor-Facilitated vs. Stand-Alone Tactical Game Training

DTIC Science & Technology

2009-01-01

Mixed Factor Repeated-Measures ANOVA showed that the two groups of leaders did not differ significantly on the time they used to complete either the...game training on tactical decision making. Thirty- two leaders were assigned to complete two urban operations- based missions (patrol and defense...using the SimFX game. These leaders worked under the direction of an instructor and interacted with peers. Thirty-seven more leaders completed the two

Intramyocellular lipid quantification: repeatability with 1H MR spectroscopy.

PubMed

Torriani, Martin; Thomas, Bijoy J; Halpern, Elkan F; Jensen, Megan E; Rosenthal, Daniel I; Palmer, William E

2005-08-01

To prospectively determine the repeatability and variability of tibialis anterior intramyocellular lipid (IMCL) quantifications performed by using 1.5-T hydrogen 1 (1H) magnetic resonance (MR) spectroscopy in healthy subjects. Institutional review board approval and written informed consent were obtained for this Health Insurance Portability and Accountability Act-compliant study. The authors examined the anterior tibial muscles of 27 healthy subjects aged 19-48 years (12 men, 15 women; mean age, 25 years) by using single-voxel short-echo-time point-resolved 1H MR spectroscopy. During a first visit, the subjects underwent 1H MR spectroscopy before and after being repositioned in the magnet bore, with voxels carefully placed on the basis of osseous landmarks. Measurements were repeated after a mean interval of 12 days. All spectra were fitted by using Java-based MR user interface (jMRUI) and LCModel software, and lipid peaks were scaled to the unsuppressed water peak (at 4.7 ppm) and the total creatine peak (at approximately 3.0 ppm). A one-way random-effects variance components model was used to determine intraday and intervisit coefficients of variation (CVs). A power analysis was performed to determine the detectable percentage change in lipid measurements for two subject sample sizes. Measurements of the IMCL methylene protons peak at a resonance of 1.3 ppm scaled to the unsuppressed water peak (IMCL(W)) that were obtained by using jMRUI software yielded the lowest CVs overall (intraday and intervisit CVs, 13.4% and 14.4%, respectively). The random-effects variance components model revealed that nonbiologic factors (equipment and repositioning) accounted for 50% of the total variability in IMCL quantifications. Power analysis for a sample size of 20 subjects revealed that changes in IMCL(W) of greater than 15% could be confidently detected between 1H MR spectroscopic measurements obtained on different days. 1H MR spectroscopy is feasible for repeatable quantification of IMCL concentrations in longitudinal studies of muscle metabolism.

WE-H-207A-04: Impact of Lesion Location On the Repeatability of 18F-NaF PET/CT

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

Lin, C; Perk, T; Harmon, S

Purpose: Quantifying the repeatability of imaging biomarkers is critical for assessing therapeutic response. While {sup 18}F-NaF PET/CT has shown to be a repeatable imaging method, research has not shown which factors may influence its repeatability. The purpose of this study was to evaluate whether the location of the lesion impacts the repeatability of quantitative {sup 18}F-NaF PET-derived SUV metrics. Methods: Metastatic castrate-resistant prostate cancer patients with multiple bone lesions received whole-body test-retest NaF PET/CT scans. Malignant bone lesions of PET-defined volume greater than 1.5 cm{sup 3} were identified by a nuclear medicine physician and automatically delineated using a SUV>15 threshold.more » The maximum (SUVmax), average (SUVmean), and total (SUVtotal) SUV were extracted from each lesion. Atlas-based segmentation was used to divide each patient skeleton into 25 skeletal regions. Test-retest repeatability of each SUV metric was assessed with coefficient of variation (CV). Results: A total of 265 malignant bone lesions from 18 patients were identified by nuclear medicine physician. The largest proportion of bone lesions were localized to the spine (41%), with 41% of those lesions localized to the thoracic spine. One-way ANOVA showed that measurement differences differed significantly for all three metrics across locations (p<0.01 for each metrics). Overall, CV was smallest for SUVmean at 5.3%, followed by SUVmax at 11.5% and SUVtotal at 20.4%. Lesions in the pubis were consistently the most repeatable (CV(SUVmax)= 5.6%, CV(SUVmean)= 0.6%, CV(SUVtotal)= 2.9%). According to SUVmean, repeatability was poorest in the cervical spine (CV = 6.2%), whereas according to SUVmax and SUVtotal, repeatability was poorest in the ribs (CV(SUVmax)= 15.0%, CV(SUVtotal)= 29.8%). Conclusion: Location of the lesion affects the repeatability of {sup 18}F-NaF PET/CT, with the ribs and cervical spine having the lowest repeatability and the pubis having the highest repeatability. These results can be used to establish location-specific response criteria for NaF PET-based treatment response assessment.« less

Intelligence Is in the Eye of the Beholder: Investigating Repeated IQ Measurements in Forensic Psychiatry

ERIC Educational Resources Information Center

Habets, Petra; Jeandarme, Inge; Uzieblo, Kasia; Oei, Karel; Bogaerts, Stefan

2015-01-01

Background: A stable assessment of cognition is of paramount importance for forensic psychiatric patients (FPP). The purpose of this study was to compare repeated measures of IQ scores in FPPs with and without intellectual disability. Methods: Repeated measurements of IQ scores in FPPs (n = 176) were collected. Differences between tests were…

Effect of Physical Therapy Students' Clinical Experiences on Clinician Productivity.

PubMed

Pivko, Susan E; Abbruzzese, Laurel D; Duttaroy, Pragati; Hansen, Ruth L; Ryans, Kathryn

2016-01-01

Physical therapy clinical education experiences (CEEs) are difficult to secure, particularly first-level CEEs. Our purpose was to determine 1) what impact student full-time CEEs have on PT clinician productivity and 2) whether there is a productivity difference between first vs final CEEs. Productivity logs, including possible factors impacting productivity, were distributed to clinician-student pairings on first and final CEEs. Two-week baseline data (without a student) were compared to weeks 1 and 6 (with a student) for 31 logs using a 2x4 repeated-measures ANOVA. In a subset of 17 logs for CEEs 8 weeks or longer, a 2x5 repeated-measures ANOVA was performed. There was a significant increase in the number of patients seen and CPT units billed by both levels of CEEs comparing weeks 1 and 6. In the subset of CEEs, 8 weeks or longer, there was a significant increase in the number of patients treated per hour at week 6 and a trend toward a change at week 8 when compared to baseline week A. The factors selected as impacting productivity were census (59%) and staffing (32%). Physical therapy clinician-student pairings showed an overall increase in productivity during both full-time first and final level CEEs.

Relationship disruption stress in human infants: a validation study with experimental and control groups.

PubMed

Haley, David W

2011-09-01

The current study examined whether the psychological stress of the still-face (SF) task (i.e. stress resulting from a parent's unresponsiveness) is a valid laboratory stress paradigm for evaluating infant cortisol reactivity. Given that factors external to the experimental paradigm, such as arriving at a new place, may cause an elevation in cortisol secretion; we tested the hypothesis that infants would show a cortisol response to the SF task but not to a normal FF task (control). Saliva was collected for cortisol measurement from 6-month-old infants (n = 31) randomly assigned to either a repeated SF task or to a continuous FF task. Parent-infant dyads were videotaped. Salivary cortisol concentration was measured at baseline, 20, and 30 min after the start of the procedure. Infant salivary cortisol concentrations showed a significant increase over time for the SF task but not for the FF task. The results provide new evidence that the repeated SF task provides a psychological challenge that is due to the SF condition rather than to some non-task related factor; these results provide internal validity for the paradigm. The study offers new insight into the role of parent-infant interactions in the activation of the infant stress response system.

Evaluation of lot-to-lot repeatability and effect of assay media choice in the recombinant Factor C assay.

PubMed

McKenzie, Jennifer Helen; Alwis, K Udeni; Sordillo, Joanne E; Kalluri, Kesava Srinivas; Milton, Donald Kirby

2011-06-01

Measurement of environmental endotoxin exposures is complicated by variability encountered using current biological assay methods arising in part from lot-to-lot variability of the Limulus-amebocyte lysate (LAL) reagents. Therefore, we investigated the lot-to-lot repeatability of commercially available recombinant Factor C (rFC) kits as an alternative to LAL. Specifically, we compared endotoxin estimates obtained from rFC assay of twenty indoor dust samples, using four different extraction and assay media, to endotoxin estimates previously obtained by Limulus amebocyte lysate (LAL) assay and amounts of 3-hydroxy fatty acids (3-OHFA) in lipopolysaccharide (LPS) using gas-chromatography mass spectroscopy (GC-MS). We found that lot-to-lot variability of the rFC assay kits does not significantly alter endotoxin estimates in house dust samples when performed using three of the four assay media tested and that choice of assay media significantly altered endotoxin estimates obtained by rFC assay of house dust samples. Our findings demonstrate lot-to-lot reproducibility of rFC assay of environmental samples and suggest that use of rFC assay performed with Tris buffer or water as the extraction and assay medium for measurement of endotoxin in dust samples may be a suitable choice for developing a standardized methodology.

SU-F-T-326: Diode Array Transmission Detector Systems Evaluation

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

Hoffman, D; Dyer, B; Kumaran Nair, C

2016-06-15

Purpose: A new transmission detector, Delta4 Discover, developed by Scandidos (Uppsala, Sweden) was evaluated for external photon beam verification and quality assurance. The device is an array of 4040 diodes designed to be mounted on the linac accessory tray to measure photon field shape, position and fluence during patient treatment. Interfractional measurements are compared to a baseline measurement made during delivery quality assurance. The aim of this work is to evaluate the stability of the device and its effect on the shape and magnitude of the treatment beam. Methods: Beam profiles, percent depth dose, and beam attenuation was measured formore » 6, 10, and 15 MV photon beams with and without the device in place for 1×1 and 30×30 cm2 fields. Changes in profile and percent depth dose was quantified to evaluate the need to recommission the treatment beam, or account for the device with a tray factor. The stability of the radiation measurements was evaluated by measuring the deviation of each diode measurement during repeated prostate VMAT treatment delivery. Results: Photon beam profiles changed by < 1.25% in the nonpenumbra regions of the 30×30 cm2 beam. Percent depth dose curves show a 5–7% increased dose at depths < 2.5cm, but agreed within 1% at depths > 2.5cm. This indicates increased skin dose, similar to the use of a physical beam wedge. The device attenuated 6, 10, and 15 MV photon beams by 1.71±0.02%, 1.36±0.03%, and 1.17±0.03%, respectively. The diode array reproduced dosimetric measurements within 0.5% standard deviation for repeated prostate VMAT measurement. Conclusion: The device demonstrated stabile radiation measurements, while not changing the treatment beam shape in a clinically significantly manner. Use of this device can be accounted for with a tray factor, as opposed to recommissioning the treatment beam.« less

Biopsychosocial-Spiritual Factors Impacting Referral to and Participation in Cardiac Rehabilitation for African American Patients: A SYSTEMATIC REVIEW.

PubMed

Koehler Hildebrandt, Aubry N; Hodgson, Jennifer L; Dodor, Bernice A; Knight, Sharon M; Rappleyea, Damon L

2016-01-01

The purposes of this systematic review were to (1) review the literature related to the demographic and biopsychosocial-spiritual factors impacting cardiac rehabilitation (CR) referral and participation of African American patients with cardiovascular disease (CVD); (2) identify barriers and facilitators to CR referral and participation for this population; (3) identify gaps in the literature; and (4) make recommendations for future research studies and interventions. The Cooper 7-step protocol for research synthesis was followed to formulate a research question and search MEDLINE via PubMed, PsycINFO via EBSCO, and CINAHL via EBSCO. A second reviewer repeated the searches performed by the first author in the initial review. A total of 1640 articles identified using the search strategy yielded 7 articles that fit the search criteria. Most studies measured demographic or social factors. Two studies measured biological factors, 1 study measured psychological factors, and no study measured spiritual factors. According to the studies reviewed, African American patients with CVD were less likely to receive a CR referral, more likely to enroll in CR with more cardiovascular risk factors, and less likely to participate in and complete CR due to factors related to low socioeconomic status (eg, lack of insurance, work conflicts, lower level of education) than non-Hispanic white patients. Further research is needed on the interaction between demographic/biopsychosocial-spiritual factors and referral to and participation of African Americans in CR in order to ensure that interventions fit the needs of this particular population.

Psychometric evaluation of the Dutch version of the Subjective Opiate Withdrawal Scale (SOWS).

PubMed

Dijkstra, Boukje A G; Krabbe, Paul F M; Riezebos, Truus G M; van der Staak, Cees P F; De Jong, Cor A J

2007-01-01

To evaluate the psychometric properties of the Dutch version of the 16-item Subjective Opiate Withdrawal Scale (SOWS). The SOWS measures withdrawal symptoms at the time of assessment. The Dutch SOWS was repeatedly administered to a sample of 272 opioid-dependent inpatients of four addiction treatment centers during rapid detoxification with or without general anesthesia. Examination of the psychometric properties of the SOWS included exploratory factor analysis, internal consistency, test-retest reliability, and criterion validity. Exploratory factor analysis of the SOWS revealed a general pattern of four factors with three items not always clustered in the same factors at different points of measurement. After excluding these items from factor analysis four factors were identified during detoxification (temperature dysregulation, tractus locomotorius, tractus gastro-intestinalis and facial disinhibition). The 13-item SOWS shows high internal consistency and test-retest reliability and good validity at different stages of withdrawal. The 13-item SOWS is a reliable and valid instrument to assess opioid withdrawal during rapid detoxification. Three items were deleted because their content does not correspond directly with opioid withdrawal symptoms. Copyright (c) 2007 S. Karger AG, Basel.

Effects of rearing environment and population origin on responses to repeated behavioural trials in cane toads (Rhinella marina).

PubMed

Gruber, Jodie; Whiting, Martin J; Brown, Gregory; Shine, Richard

2018-05-02

Behavioural response to repeated trials in captivity can be driven by many factors including rearing environment, population of origin, habituation to captivity/trial conditions and an individual's behavioural type (e.g., bold versus shy). We tested the effect of rearing environment (captive raised common-garden versus wild-caught) and population origin (range-edge versus range-front) on the responses of invasive cane toads (Rhinella marina) to repeated exploration and risk-taking assays in captivity. We found that behavioural responses to identical assays performed on two occasions were complex and showed few consistent patterns based on rearing environment or population of origin. However, behavioural traits were repeatable across Trial Blocks when all sample populations were grouped together, indicating general consistency in individual toad behaviour across repeated behavioural assays. Our findings exemplify the complexity and unpredictability of behavioural responses and their effects on the repeatability and interpretation of behavioural traits across repeated behavioural assays in captivity. To meaningfully interpret the results from repeated behavioural assays, we need to consider how multiple factors may affect behavioural responses to these tests and importantly, how these responses may affect the repeatability of behavioural traits across time. Copyright © 2018. Published by Elsevier B.V.

Improved knowledge retention among clinical pharmacy students using an anthropology classroom assessment technique.

PubMed

Whitley, Heather P; Parton, Jason M

2014-09-15

To adapt a classroom assessment technique (CAT) from an anthropology course to a diabetes module in a clinical pharmacy skills laboratory and to determine student knowledge retention from baseline. Diabetes item stems, focused on module objectives, replaced anthropology terms. Answer choices, coded to Bloom's Taxonomy, were expanded to include higher-order thinking. Students completed the online 5-item probe 4 times: prelaboratory lecture, postlaboratory, and at 6 months and 12 months after laboratory. Statistical analyses utilized a single factor, repeated measures design using rank transformations of means with a Mann-Whitney-Wilcoxon test. The CAT revealed a significant increase in knowledge from prelaboratory compared to all postlaboratory measurements (p<0.0001). Significant knowledge retention was maintained with basic terms, but declined with complex terms between 6 and 12 months. The anthropology assessment tool was effectively adapted using Bloom's Taxonomy as a guide and, when used repeatedly, demonstrated knowledge retention. Minimal time was devoted to application of the probe making it an easily adaptable CAT.

Weight Shame, Social Connection, and Depressive Symptoms in Late Adolescence

PubMed Central

Brewis, Alexandra A.; Bruening, Meg

2018-01-01

Child and adolescent obesity is increasingly the focus of interventions, because it predicts serious disease morbidity later in life. However, social environments that permit weight-related stigma and body shame may make weight control and loss more difficult. Rarely do youth obesity interventions address these complexities. Drawing on repeated measures in a large sample (N = 1443) of first-year (freshman), campus-resident university students across a nine-month period, we model how weight-related shame predicts depressive symptom levels, how being overweight (assessed by anthropometric measures) shapes that risk, and how social connection (openness to friendship) might mediate/moderate. Body shame directly, clearly, and repeatedly predicts depression symptom levels across the whole school year for all students, but overweight youth have significantly elevated risk. Social connections mediate earlier in the school year, and in all phases moderate, body shame effects on depression. Youth obesity interventions would be well-served recognizing and incorporating the influential roles of social-environmental factors like weight stigma and friendship in program design. PMID:29723962

Weight Shame, Social Connection, and Depressive Symptoms in Late Adolescence.

PubMed

Brewis, Alexandra A; Bruening, Meg

2018-05-01

Child and adolescent obesity is increasingly the focus of interventions, because it predicts serious disease morbidity later in life. However, social environments that permit weight-related stigma and body shame may make weight control and loss more difficult. Rarely do youth obesity interventions address these complexities. Drawing on repeated measures in a large sample ( N = 1443) of first-year (freshman), campus-resident university students across a nine-month period, we model how weight-related shame predicts depressive symptom levels, how being overweight (assessed by anthropometric measures) shapes that risk, and how social connection (openness to friendship) might mediate/moderate. Body shame directly, clearly, and repeatedly predicts depression symptom levels across the whole school year for all students, but overweight youth have significantly elevated risk. Social connections mediate earlier in the school year, and in all phases moderate, body shame effects on depression. Youth obesity interventions would be well-served recognizing and incorporating the influential roles of social-environmental factors like weight stigma and friendship in program design.

[Reproducibility of subjective refraction measurement].

PubMed

Grein, H-J; Schmidt, O; Ritsche, A

2014-11-01

Reproducibility of subjective refraction measurement is limited by various factors. The main factors affecting reproducibility include the characteristics of the measurement method and of the subject and the examiner. This article presents the results of a study on this topic, focusing on the reproducibility of subjective refraction measurement in healthy eyes. The results of previous studies are not all presented in the same way by the respective authors and cannot be fully standardized without consulting the original scientific data. To the extent that they are comparable, the results of our study largely correspond largely with those of previous investigations: During repeated subjective refraction measurement, 95% of the deviation from the mean value was approximately ±0.2 D to ±0.65 D for the spherical equivalent and cylindrical power. The reproducibility of subjective refraction measurement in healthy eyes is limited, even under ideal conditions. Correct assessment of refraction results is only feasible after identifying individual variability. Several measurements are required. Refraction cannot be measured without a tolerance range. The English full-text version of this article is available at SpringerLink (under supplemental).

Effect of post crosslinking haze on the repeatability of Scheimpflug-based and slit-scanning imaging devices

PubMed Central

Shetty, Rohit; Agrawal, Aarti; Deshmukh, Rashmi; Kaweri, Luci; Rao, Harsha L; Nagaraja, Harsha; Jayadev, Chaitra

2017-01-01

Purpose: The aim of this study was to analyze the effect of postcollagen crosslinking (CXL) haze on the measurement and repeatability of pachymetry and mean keratometry (Km) of four corneal topographers. Materials and Methods: Sixty eyes of sixty patients with progressive keratoconus who had undergone accelerated CXL (ACXL) underwent imaging with a scanning slit imaging device (Orbscan II) and three Scheimpflug imaging devices (Pentacam HR, Sirius, and Galilei). Post-ACXL haze was measured using the densitometry software on the Pentacam HR. Readings of the thinnest corneal thickness (TCT) and Km from three scans of each device were analyzed. Effect of haze on the repeatability of TCT and Km measurements was evaluated using regression models. Repeatability was assessed by coefficient of variation. Results: Corneal densitometry in different zones affected the repeatability of TCT measurement of Orbscan (P < 0.05) significantly but not the repeatability of TCT with Pentacam HR and Sirius (P = 0.03 and 0.05, respectively). Km values were affected by haze when measured with the Pentacam HR (P < 0.05). The repeatability of Km readings for all devices was unaffected by haze. In the anterior 0–2 mm and 2–6 mm zone, TCT (P = 0.43 and 0.45, respectively), Km values (P = 0.4 and 0.6, respectively), repeatability of TCT (P = 0.1 in both zones), and Km (P = 0.5 and 0.1, respectively) with Galilei were found to be the most reliable. Conclusion: Galilei measurements appear to be least affected by post-ACXL haze when compared with other devices. Hence, topography measurements in the presence of haze need to be interpreted with caution. PMID:28513495

Regression dilution bias: tools for correction methods and sample size calculation.

PubMed

Berglund, Lars

2012-08-01

Random errors in measurement of a risk factor will introduce downward bias of an estimated association to a disease or a disease marker. This phenomenon is called regression dilution bias. A bias correction may be made with data from a validity study or a reliability study. In this article we give a non-technical description of designs of reliability studies with emphasis on selection of individuals for a repeated measurement, assumptions of measurement error models, and correction methods for the slope in a simple linear regression model where the dependent variable is a continuous variable. Also, we describe situations where correction for regression dilution bias is not appropriate. The methods are illustrated with the association between insulin sensitivity measured with the euglycaemic insulin clamp technique and fasting insulin, where measurement of the latter variable carries noticeable random error. We provide software tools for estimation of a corrected slope in a simple linear regression model assuming data for a continuous dependent variable and a continuous risk factor from a main study and an additional measurement of the risk factor in a reliability study. Also, we supply programs for estimation of the number of individuals needed in the reliability study and for choice of its design. Our conclusion is that correction for regression dilution bias is seldom applied in epidemiological studies. This may cause important effects of risk factors with large measurement errors to be neglected.

Comparison of optical coherence tomography and fundus photography for measuring the optic disc size.

PubMed

Neubauer, Aljoscha S; Krieglstein, Tina R; Chryssafis, Christos; Thiel, Martin; Kampik, Anselm

2006-01-01

To assess the agreement and repeatability of optic nerve head (ONH) size measurements by optical coherence tomography (OCT) as compared to conventional planimetry of fundus photographs in normal eyes. For comparison with planimetry the absolute size of the ONH of 25 eyes from 25 normal subjects were measured by both OCT and digital fundus photography (Zeiss FF camera 450). Repeatability of automated Stratus OCT measurements were investigated by repeatedly measuring the optic disc in five normal subjects. Mean disc size was 1763 +/- 186 vertically and 1632 +/- 160 microm horizontally on planimetry. On OCT, values of 1772 +/- 317 microm vertically (p = 0.82) and a significantly smaller horizontal diameter of 1492 +/- 302 microm (p = 0.04) were obtained. The 95% limits of agreement were (-546 microm; +527 microm) for vertical and (-502 microm; +782 microm) for horizontal planimetric compared to OCT measurements. In some cases large discrepancies existed. Repeatability of automatic measurements of the optic disc by OCT was moderately good with intra-class correlation coefficients (ICC) of 0.78 horizontally and 0.83 vertically. The coefficient of repeatability indicating instrument precision was 80 microm for horizontal and 168 microm for vertical measurements. OCT can be used to determine optic disc margins in moderate agreement with planimetry in normal subjects. However, in some cases significant disagreement with photographic assessment may occur making manual inspection advisable. Automatic disc detection by OCT is moderately repeatable.

Subjective and psychophysiological indices of listening effort in a competing-talker task

PubMed Central

Mackersie, Carol L.; Cones, Heather

2010-01-01

Background The effects of noise and other competing backgrounds on speech recognition performance are well documented. There is less information, however, on listening effort and stress experienced by listeners during a speech recognition task that requires inhibition of competing sounds. Purpose The purpose was a) to determine if psychophysiological indices of listening effort were more sensitive than performance measures (percentage correct) obtained near ceiling level during a competing speech task b) to determine the relative sensitivity of four psychophysiological measures to changes in task demand and c) to determine the relationships between changes in psychophysiological measures and changes in subjective ratings of stress and workload. Research Design A repeated-measures experimental design was used to examine changes in performance, psychophysiological measures, and subjective ratings in response to increasing task demand. Study Sample Fifteen adults with normal hearing participated in the study. The mean age of the participants was 27 (range: 24–54). Data Collection and Analysis Psychophysiological recordings of heart rate, skin conductance, skin temperature, and electromyographic activity (EMG) were obtained during listening tasks of varying demand. Materials from the Dichotic Digits Test were used to modulate task demand. The three levels of tasks demand were: single digits presented to one ear (low-demand reference condition), single digits presented simultaneously to both ears (medium demand), and a series of two digits presented simultaneously to both ears (high demand). Participants were asked to repeat all the digits they heard while psychophysiological activity was recorded simultaneously. Subjective ratings of task load were obtained after each condition using the NASA-TLX questionnaire. Repeated-measures analyses of variance were completed for each measure using task demand and session as factors. Results Mean performance was higher than 96% for all listening tasks. There was no significant change in performance across listening conditions for any listener. There was, however, a significant increase in mean skin conductance and EMG activity as task demand increased. Heart rate and skin temperature did not change significantly. There was no strong association between subjective and psychophysiological measures, but all participants with mean normalized effort ratings of greater than 4.5 (i.e. effort increased by a factor of at least 4.5) showed significant changes in skin conductance. Conclusions Even in the absence of substantial performance changes, listeners may experience changes in subjective and psychophysiological responses consistent with activation of a stress response. Skin conductance appears to be the most promising measure for evaluating individual changes in psychophysiological responses during listening tasks. PMID:21463566

Subjective and psychophysiological indexes of listening effort in a competing-talker task.

PubMed

Mackersie, Carol L; Cones, Heather

2011-02-01

The effects of noise and other competing backgrounds on speech recognition performance are well documented. There is less information, however, on listening effort and stress experienced by listeners during a speech-recognition task that requires inhibition of competing sounds. The purpose was (a) to determine if psychophysiological indexes of listening effort were more sensitive than performance measures (percentage correct) obtained near ceiling level during a competing speech task, (b) to determine the relative sensitivity of four psychophysiological measures to changes in task demand, and (c) to determine the relationships between changes in psychophysiological measures and changes in subjective ratings of stress and workload. A repeated-measures experimental design was used to examine changes in performance, psychophysiological measures, and subjective ratings in response to increasing task demand. Fifteen adults with normal hearing participated in the study. The mean age of the participants was 27 (range: 24-54). Psychophysiological recordings of heart rate, skin conductance, skin temperature, and electromyographic (EMG) activity were obtained during listening tasks of varying demand. Materials from the Dichotic Digits Test were used to modulate task demand. The three levels of task demand were single digits presented to one ear (low-demand reference condition), single digits presented simultaneously to both ears (medium demand), and a series of two digits presented simultaneously to both ears (high demand). Participants were asked to repeat all the digits they heard, while psychophysiological activity was recorded simultaneously. Subjective ratings of task load were obtained after each condition using the National Aeronautics and Space Administration Task Load Index questionnaire. Repeated-measures analyses of variance were completed for each measure using task demand and session as factors. Mean performance was higher than 96% for all listening tasks. There was no significant change in performance across listening conditions for any listener. There was, however, a significant increase in mean skin conductance and EMG activity as task demand increased. Heart rate and skin temperature did not change significantly. There was no strong association between subjective and psychophysiological measures, but all participants with mean normalized effort ratings of greater than 4.5 (i.e., effort increased by a factor of at least 4.5) showed significant changes in skin conductance. Even in the absence of substantial performance changes, listeners may experience changes in subjective and psychophysiological responses consistent with the activation of a stress response. Skin conductance appears to be the most promising measure for evaluating individual changes in psychophysiological responses during listening tasks. American Academy of Audiology.

Repeated injections of nicergoline increase the nerve growth factor level in the aged rat brain.

PubMed

Nishio, T; Sunohara, N; Furukawa, S; Akiguchi, I; Kudo, Y

1998-03-01

We studied whether nicergoline, clinically active in chronic cerebrovascular insufficiency, influences nerve growth factor (NGF) levels in the rat brain. In young Fischer rats, repeated intraperitoneal injections of nicergoline (0.3 and 1.0 mg/kg body weight) did not show any effects on frontal NGF contents determined by a highly sensitive enzyme immunoassay. In aged rats, 22-month-old, however, repeated injections of nicergoline (1.0 mg/kg body weight) induced a significant increase in the NGF level in the frontal region.

Effects of repeated Valsalva maneuver straining on cardiac and vasoconstrictive baroreflex responses

NASA Technical Reports Server (NTRS)

Convertino, Victor A.; Ratliff, Duane A.; Doerr, Donald F.; Ludwig, David A.; Muniz, Gary W.; Benedetti, Erik; Chavarria, Jose; Koreen, Susan; Nguyen, Claude; Wang, Jeff

2003-01-01

INTRODUCTION: We hypothesized that repeated respiratory straining maneuvers (repeated SM) designed to elevate arterial BPs (arterial baroreceptor loading) would acutely increase baroreflex responses. METHODS: We tested this hypothesis by measuring cardiac baroreflex responses to carotid baroreceptor stimulation (neck pressures), and changes in heart rate and diastolic BP after reductions in BP induced by a 15-s Valsalva maneuver in 10 female and 10 male subjects at 1, 3, 6, and 24 h after performing repeated SM. Baroreflex responses were also measured in each subject at 1, 3, 6, and 24 h at the same time on a separate day without repeated SM (control) in a randomized, counter-balanced cross-over experimental design. RESULTS: There was no statistical difference in carotid-cardiac and peripheral vascular baroreflex responses measured across time following repeated SM compared with the control condition. Integrated cardiac baroreflex response (deltaHR/ deltaSBP) measured during performance of a Valsalva maneuver was increased by approximately 50% to 1.1 +/- 0.2 bpm x mm Hg(-1) at 1 h and 1.0 +/- 0.1 bpm x mm Hg(-1) at 3 h following repeated SM compared with the control condition (0.7 +/- 0.1 bpm x mm Hg(-1) at both 1 and 3 h, respectively). However, integrated cardiac baroreflex response after repeated SM returned to control levels at 6 and 24 h after training. These responses did not differ between men and women. CONCLUSIONS: Our results are consistent with the notion that arterial baroreceptor loading induced by repeated SM increased aortic, but not carotid, cardiac baroreflex responses for as long as 3 h after repeated SM. We conclude that repeated SM increases cardiac baroreflex responsiveness which may provide patients, astronauts, and high-performance aircraft pilots with protection from development of orthostatic hypotension.

Birth wind and fire: raising awareness to operating room fires during delivery.

PubMed

Wolf, Omer; Weissman, Oren; Harats, Moti; Farber, Nimrod; Stavrou, Demetris; Tessone, Ariel; Zilinsky, Isaac; Winkler, Eyal; Haik, Josef

2013-09-01

We researched whether the obstetric operating room (OR) qualified as a fire-risk environment so as to take preventive measures accordingly. We analyzed a series of iatrogenic burns inflicted during birth by collecting clinical data and comparing it with known OR fire risk factors and with other factors that repeated in all cases in search of unique characteristics of the obstetric OR. All three cases shared in common the same type of oxygen-rich open ventilation system, alcohol-based prepping solution, and the hastiness of cesarean delivery while spontaneous vaginal delivery was already in progress. The obstetric OR is, as suspected, a fire-prone zone in more ways than the regular OR. Therefore, preventive measures should be undertaken and awareness for the possibility for such occurrences should be raised.

Heart Rate and Respiratory Rate Influence on Heart Rate Variability Repeatability: Effects of the Correction for the Prevailing Heart Rate

PubMed Central

Gąsior, Jakub S.; Sacha, Jerzy; Jeleń, Piotr J.; Zieliński, Jakub; Przybylski, Jacek

2016-01-01

Background: Since heart rate variability (HRV) is associated with average heart rate (HR) and respiratory rate (RespRate), alterations in these parameters may impose changes in HRV. Hence the repeatability of HRV measurements may be affected by differences in HR and RespRate. The study aimed to evaluate HRV repeatability and its association with changes in HR and RespRate. Methods: Forty healthy volunteers underwent two ECG examinations 7 days apart. Standard HRV indices were calculated from 5-min ECG recordings. The ECG-derived respiration signal was estimated to assess RespRate. To investigate HR impact on HRV, HRV parameters were corrected for prevailing HR. Results: Differences in HRV parameters between the measurements were associated with the changes in HR and RespRate. However, in multiple regression analysis only HR alteration proved to be independent determinant of the HRV differences—every change in HR by 1 bpm changed HRV values by 16.5% on average. After overall removal of HR impact on HRV, coefficients of variation of the HRV parameters significantly dropped on average by 26.8% (p < 0.001), i.e., by the same extent HRV reproducibility improved. Additionally, the HRV correction for HR decreased association between RespRate and HRV. Conclusions: In stable conditions, HR but not RespRate is the most powerful factor determining HRV reproducibility and even a minimal change of HR may considerably alter HRV. However, the removal of HR impact may significantly improve HRV repeatability. The association between HRV and RespRate seems to be, at least in part, HR dependent. PMID:27588006

The Spring 1985 high precision baseline test of the JPL GPS-based geodetic system

NASA Technical Reports Server (NTRS)

Davidson, John M.; Thornton, Catherine L.; Stephens, Scott A.; Blewitt, Geoffrey; Lichten, Stephen M.; Sovers, Ojars J.; Kroger, Peter M.; Skrumeda, Lisa L.; Border, James S.; Neilan, Ruth E.

1987-01-01

The Spring 1985 High Precision Baseline Test (HPBT) was conducted. The HPBT was designed to meet a number of objectives. Foremost among these was the demonstration of a level of accuracy of 1 to 2:10 to the 7th power, or better, for baselines ranging in length up to several hundred kilometers. These objectives were all met with a high degree of success, with respect to the demonstration of system accuracy in particular. The results from six baselines ranging in length from 70 to 729 km were examined for repeatability and, in the case of three baselines, were compared to results from colocated VLBI systems. Repeatability was found to be 5:10 to the 8th power (RMS) for the north baseline coordinate, independent of baseline length, while for the east coordinate RMS repeatability was found to be larger than this by factors of 2 to 4. The GPS-based results were found to be in agreement with those from colocated VLBI measurements, when corrected for the physical separations of the VLBI and CPG antennas, at the level of 1 to 2:10 to the 7th power in all coordinates, independent of baseline length. The results for baseline repeatability are consistent with the current GPA error budget, but the GPS-VLBI intercomparisons disagree at a somewhat larger level than expected. It is hypothesized that these differences may result from errors in the local survey measurements used to correct for the separations of the GPS and VLBI antenna reference centers.

The study design elements employed by researchers in preclinical animal experiments from two research domains and implications for automation of systematic reviews.

PubMed

O'Connor, Annette M; Totton, Sarah C; Cullen, Jonah N; Ramezani, Mahmood; Kalivarapu, Vijay; Yuan, Chaohui; Gilbert, Stephen B

2018-01-01

Systematic reviews are increasingly using data from preclinical animal experiments in evidence networks. Further, there are ever-increasing efforts to automate aspects of the systematic review process. When assessing systematic bias and unit-of-analysis errors in preclinical experiments, it is critical to understand the study design elements employed by investigators. Such information can also inform prioritization of automation efforts that allow the identification of the most common issues. The aim of this study was to identify the design elements used by investigators in preclinical research in order to inform unique aspects of assessment of bias and error in preclinical research. Using 100 preclinical experiments each related to brain trauma and toxicology, we assessed design elements described by the investigators. We evaluated Methods and Materials sections of reports for descriptions of the following design elements: 1) use of comparison group, 2) unit of allocation of the interventions to study units, 3) arrangement of factors, 4) method of factor allocation to study units, 5) concealment of the factors during allocation and outcome assessment, 6) independence of study units, and 7) nature of factors. Many investigators reported using design elements that suggested the potential for unit-of-analysis errors, i.e., descriptions of repeated measurements of the outcome (94/200) and descriptions of potential for pseudo-replication (99/200). Use of complex factor arrangements was common, with 112 experiments using some form of factorial design (complete, incomplete or split-plot-like). In the toxicology dataset, 20 of the 100 experiments appeared to use a split-plot-like design, although no investigators used this term. The common use of repeated measures and factorial designs means understanding bias and error in preclinical experimental design might require greater expertise than simple parallel designs. Similarly, use of complex factor arrangements creates novel challenges for accurate automation of data extraction and bias and error assessment in preclinical experiments.

Repeatability Assessment by ISO 11843-7 in Quantitative HPLC for Herbal Medicines.

PubMed

Chen, Liangmian; Kotani, Akira; Hakamata, Hideki; Tsutsumi, Risa; Hayashi, Yuzuru; Wang, Zhimin; Kusu, Fumiyo

2015-01-01

We have proposed an assessment methods to estimate the measurement relative standard deviation (RSD) of chromatographic peaks in quantitative HPLC for herbal medicines by the methodology of ISO 11843 Part 7 (ISO 11843-7:2012), which provides detection limits stochastically. In quantitative HPLC with UV detection (HPLC-UV) of Scutellaria Radix for the determination of baicalin, the measurement RSD of baicalin by ISO 11843-7:2012 stochastically was within a 95% confidence interval of the statistically obtained RSD by repetitive measurements (n = 6). Thus, our findings show that it is applicable for estimating of the repeatability of HPLC-UV for determining baicalin without repeated measurements. In addition, the allowable limit of the "System repeatability" in "Liquid Chromatography" regulated in a pharmacopoeia can be obtained by the present assessment method. Moreover, the present assessment method was also successfully applied to estimate the measurement RSDs of quantitative three-channel liquid chromatography with electrochemical detection (LC-3ECD) of Chrysanthemi Flos for determining caffeoylquinic acids and flavonoids. By the present repeatability assessment method, reliable measurement RSD was obtained stochastically, and the experimental time was remarkably reduced.

Sample size considerations for studies of intervention efficacy in the occupational setting.

PubMed

Lazovich, Deann; Murray, David M; Brosseau, Lisa M; Parker, David L; Milton, F Thomas; Dugan, Siobhan K

2002-03-01

Due to a shared environment and similarities among workers within a worksite, the strongest analytical design to evaluate the efficacy of an intervention to reduce occupational health or safety hazards is to randomly assign worksites, not workers, to the intervention and comparison conditions. Statistical methods are well described for estimating the sample size when the unit of assignment is a group but these methods have not been applied in the evaluation of occupational health and safety interventions. We review and apply the statistical methods for group-randomized trials in planning a study to evaluate the effectiveness of technical/behavioral interventions to reduce wood dust levels among small woodworking businesses. We conducted a pilot study in five small woodworking businesses to estimate variance components between and within worksites and between and within workers. In each worksite, 8 h time-weighted dust concentrations were obtained for each production employee on between two and five occasions. With these data, we estimated the parameters necessary to calculate the percent change in dust concentrations that we could detect (alpha = 0.05, power = 80%) for a range of worksites per condition, workers per worksite and repeat measurements per worker. The mean wood dust concentration across woodworking businesses was 4.53 mg/m3. The measure of similarity among workers within a woodworking business was large (intraclass correlation = 0.5086). Repeated measurements within a worker were weakly correlated (r = 0.1927) while repeated measurements within a worksite were strongly correlated (r = 0.8925). The dominant factor in the sample size calculation was the number of worksites per condition, with the number of workers per worksite playing a lesser role. We also observed that increasing the number of repeat measurements per person had little benefit given the low within-worker correlation in our data. We found that 30 worksites per condition and 10 workers per worksite would give us 80% power to detect a reduction of approximately 30% in wood dust levels (alpha = 0.05). Our results demonstrate the application of the group-randomized trials methodology to evaluate interventions to reduce occupational hazards. The methodology is widely applicable and not limited to the context of wood dust reduction.

Changes in the cutting efficiency of different types of dental diamond rotary instrument with repeated cuts and disinfection.

PubMed

Bae, Jin-Hyuk; Yi, Jaeyoung; Kim, Sungtae; Shim, June-Sung; Lee, Keun-Woo

2014-01-01

Cutting efficiency is one of the most important factors to consider when a specific dental diamond rotary instrument is selected. However, the selection of a dental diamond rotary instrument is based on clinical experience rather than any scientific evidence. The purpose of this study was to identify how the cutting efficiency of different types of dental diamond rotary instrument changed with repeated cuts and disinfection. Four types of diamond rotary instrument from 2 dental manufacturers (Shofu, Jin Dental) were investigated with a high-speed air-turbine handpiece. The groups were as follows: S cham group (n=10): chamfer design from Shofu; J cham group (n=10): chamfer design from Jin Dental; S thin group (n=10): thin tapered design from Shofu; J thin group (n=10): thin tapered design from Jin Dental. Changes in the cutting efficiency of diamond rotary instruments on glass ceramic blocks were measured after repeated cuts. Changes in cutting efficiency also were measured for 30 diamond rotary instruments, the same type as those used in group J cham after disinfection with ethylene oxide gas, immersion in solution, or autoclaving. One-way ANOVA, 2-way ANOVA, and repeated-measures ANOVA were used to identify differences in cutting efficiency, in total cutting efficiency, and change trend in cutting efficiency (α=.05). The Tukey honestly significant difference method was used for the post hoc tests. The principal metal components of the diamond rotary instruments were detected with x-ray spectrometry. The mean (standard deviation [SD]) total cutting efficiency after 10 cuts in the 4 groups was in the following order: J cham group (0.210 ± 0.064 g/min) > S cham group (0.170 ± 0.064 g/min) > J thin group (0.130 ± 0.042 g/min) > S thin group (0.010 ± 0.040 g/min) (P<.05).The decrease in the cutting efficiency was greatest after the first cut. The cutting efficiency was not influenced by repeated disinfection. The cutting efficiencies of diamond rotary instruments with different designs and particle sizes showed a decreasing trend after repeated cuts but did not show any change after various disinfecting procedures. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Repeatability and reproducibility of ocular biometry using a new noncontact optical low-coherence interferometer.

PubMed

Huang, Jinhai; Savini, Giacomo; Wu, Fan; Yu, Xinxin; Yang, Jing; Yu, Ayong; Yu, Ye; Wang, Qinmei

2015-10-01

To assess the precision of ocular biometry with a new noncontact optical low-coherence interferometer (Aladdin) in healthy subjects and patients with cataracts. Eye Hospital of Wenzhou Medical University, Wenzhou, China. Observational cross-sectional study. Eyes from healthy subjects and eyes from patients with cataracts were examined with the new interferometer. Axial length (AL), anterior chamber depth (ACD), keratometry (K), and white-to-white (WTW) values were measured by 2 operators. The test-retest repeatability, coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were calculated to evaluate intraoperator repeatability. Different-operator comparison was analyzed with paired t tests and Bland-Altman plots to assess interoperator reproducibility. Ninety-eight people were enrolled for this study, of which 52 eyes were from healthy subjects and 46 eyes were from patients with cataracts. The AL was the most repeatable and reproducible parameter. The ACD, K values, and WTW measurements were highly repeatable in healthy subjects with CoV less than 0.89% and ICC more than 0.94. However, in patients with cataracts, high repeatability could only be observed for AL, ACD, and K values, whereas WTW measurement had test-retest repeatability of 0.80 mm and an ICC of 0.795. Bland-Altman analysis also showed good agreement between the 2 operators for ocular component measurements, except that the WTW in patients with cataracts had wider 95% limits of agreement (range -0.88 to 0.95 mm). The new biometer showed excellent intraoperator repeatability and interoperator reproducibility for AL, ACD, and K values measurements in both groups. The precision of WTW measurements was lower in patients with cataracts. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Assessment of repeatability of a wireless, inertial sensor-based lameness evaluation system for horses.

PubMed

Keegan, Kevin G; Kramer, Joanne; Yonezawa, Yoshiharu; Maki, Hiromitchi; Pai, P Frank; Dent, Eric V; Kellerman, Thomas E; Wilson, David A; Reed, Shannon K

2011-09-01

To determine repeatability of a wireless, inertial sensor-based lameness evaluation system in horses. 236 horses. Horses were from 2 to 29 years of age and of various breeds and lameness disposition. All horses were instrumented with a wireless, inertial sensor-based motion analysis system on the head (accelerometer), pelvis (midline croup region [accelerometer]), and right forelimb (gyroscope) before evaluation in 2 consecutive trials, approximately 5 minutes apart, as the horse was trotted in a straight line. Signal-processing algorithms generated overall trial asymmetry measures for vertical head and pelvic movement and stride-by-stride differences in head and pelvic maximum and minimum positions between right and left sides of each stride. Repeatability was determined, and trial difference was determined for groups of horses with various numbers of strides for which data were collected per trial. Inertial sensor-based measures of torso movement asymmetry were repeatable. Repeatability for measures of torso asymmetry for determination of hind limb lameness was slightly greater than that for forelimb lameness. Collecting large numbers of strides degraded stride-to-stride repeatability but did not degrade intertrial repeatability. The inertial sensor system used to measure asymmetry of head and pelvic movement as an aid in the detection and evaluation of lameness in horses trotting in a straight line was sufficiently repeatable to investigate for clinical use.

Reliability of a Computerized Neurocognitive Test in Baseline Concussion Testing of High School Athletes.

PubMed

MacDonald, James; Duerson, Drew

2015-07-01

Baseline assessments using computerized neurocognitive tests are frequently used in the management of sport-related concussions. Such testing is often done on an annual basis in a community setting. Reliability is a fundamental test characteristic that should be established for such tests. Our study examined the test-retest reliability of a computerized neurocognitive test in high school athletes over 1 year. Repeated measures design. Two American high schools. High school athletes (N = 117) participating in American football or soccer during the 2011-2012 and 2012-2013 academic years. All study participants completed 2 baseline computerized neurocognitive tests taken 1 year apart at their respective schools. The test measures performance on 4 cognitive tasks: identification speed (Attention), detection speed (Processing Speed), one card learning accuracy (Learning), and one back speed (Working Memory). Reliability was assessed by measuring the intraclass correlation coefficient (ICC) between the repeated measures of the 4 cognitive tasks. Pearson and Spearman correlation coefficients were calculated as a secondary outcome measure. The measure for identification speed performed best (ICC = 0.672; 95% confidence interval, 0.559-0.760) and the measure for one card learning accuracy performed worst (ICC = 0.401; 95% confidence interval, 0.237-0.542). All tests had marginal or low reliability. In a population of high school athletes, computerized neurocognitive testing performed in a community setting demonstrated low to marginal test-retest reliability on baseline assessments 1 year apart. Further investigation should focus on (1) improving the reliability of individual tasks tested, (2) controlling for external factors that might affect test performance, and (3) identifying the ideal time interval to repeat baseline testing in high school athletes. Computerized neurocognitive tests are used frequently in high school athletes, often within a model of baseline testing of asymptomatic individuals before the start of a sporting season. This study adds to the evidence that suggests in this population such testing may lack sufficient reliability to support clinical decision making.

Repeat Syphilis Among Men Who Have Sex With Men in California, 2002–2006: Implications for Syphilis Elimination Efforts

PubMed Central

Chew Ng, Rilene A.; Katz, Kenneth A.; Bernstein, Kyle T.; Samuel, Michael C.; Kerndt, Peter R.; Bolan, Gail

2012-01-01

Objectives. We examined rates of and risk factors for repeat syphilis infection among men who have sex with men (MSM) in California. Methods. We analyzed 2002 to 2006 California syphilis surveillance system data. Results. During the study period, a mean of 5.9% (range: 4.9%–7.1% per year) of MSM had a repeat primary or secondary (PS) syphilis infection within 2 years of an initial infection. There was no significant increase in the annual proportion of MSM with a repeat syphilis infection (P = .42). In a multivariable model, factors associated with repeat syphilis infection were HIV infection (odds ratio [OR] = 1.65; 95% confidence interval [CI] = 1.14, 2.37), Black race (OR = 1.84; 95% CI = 1.12, 3.04), and 10 or more recent sex partners (OR = 1.99; 95% CI = 1.12, 3.50). Conclusions. Approximately 6% of MSM in California have a repeat PS syphilis infection within 2 years of an initial infection. HIV infection, Black race, and having multiple sex partners are associated with increased odds of repeat infection. Syphilis elimination efforts should include messages about the risk for repeat infection and the importance of follow-up testing. Public health attention to individuals repeatedly infected with syphilis may help reduce local disease burdens. PMID:22095364

Environmental stress induces trinucleotide repeat mutagenesis in human cells

PubMed Central

Chatterjee, Nimrat; Lin, Yunfu; Santillan, Beatriz A.; Yotnda, Patricia; Wilson, John H.

2015-01-01

The dynamic mutability of microsatellite repeats is implicated in the modification of gene function and disease phenotype. Studies of the enhanced instability of long trinucleotide repeats (TNRs)—the cause of multiple human diseases—have revealed a remarkable complexity of mutagenic mechanisms. Here, we show that cold, heat, hypoxic, and oxidative stresses induce mutagenesis of a long CAG repeat tract in human cells. We show that stress-response factors mediate the stress-induced mutagenesis (SIM) of CAG repeats. We show further that SIM of CAG repeats does not involve mismatch repair, nucleotide excision repair, or transcription, processes that are known to promote TNR mutagenesis in other pathways of instability. Instead, we find that these stresses stimulate DNA rereplication, increasing the proportion of cells with >4 C-value (C) DNA content. Knockdown of the replication origin-licensing factor CDT1 eliminates both stress-induced rereplication and CAG repeat mutagenesis. In addition, direct induction of rereplication in the absence of stress also increases the proportion of cells with >4C DNA content and promotes repeat mutagenesis. Thus, environmental stress triggers a unique pathway for TNR mutagenesis that likely is mediated by DNA rereplication. This pathway may impact normal cells as they encounter stresses in their environment or during development or abnormal cells as they evolve metastatic potential. PMID:25775519

Environmental stress induces trinucleotide repeat mutagenesis in human cells.

PubMed

Chatterjee, Nimrat; Lin, Yunfu; Santillan, Beatriz A; Yotnda, Patricia; Wilson, John H

2015-03-24

The dynamic mutability of microsatellite repeats is implicated in the modification of gene function and disease phenotype. Studies of the enhanced instability of long trinucleotide repeats (TNRs)-the cause of multiple human diseases-have revealed a remarkable complexity of mutagenic mechanisms. Here, we show that cold, heat, hypoxic, and oxidative stresses induce mutagenesis of a long CAG repeat tract in human cells. We show that stress-response factors mediate the stress-induced mutagenesis (SIM) of CAG repeats. We show further that SIM of CAG repeats does not involve mismatch repair, nucleotide excision repair, or transcription, processes that are known to promote TNR mutagenesis in other pathways of instability. Instead, we find that these stresses stimulate DNA rereplication, increasing the proportion of cells with >4 C-value (C) DNA content. Knockdown of the replication origin-licensing factor CDT1 eliminates both stress-induced rereplication and CAG repeat mutagenesis. In addition, direct induction of rereplication in the absence of stress also increases the proportion of cells with >4C DNA content and promotes repeat mutagenesis. Thus, environmental stress triggers a unique pathway for TNR mutagenesis that likely is mediated by DNA rereplication. This pathway may impact normal cells as they encounter stresses in their environment or during development or abnormal cells as they evolve metastatic potential.

Regulation of cell fate determination by single-repeat R3 MYB transcription factors in Arabidopsis

PubMed Central

Wang, Shucai; Chen, Jin-Gui

2014-01-01

MYB transcription factors regulate multiple aspects of plant growth and development. Among the large family of MYB transcription factors, single-repeat R3 MYBs are characterized by their short sequence (<120 amino acids) consisting largely of the single MYB DNA-binding repeat. In the model plant Arabidopsis, R3 MYBs mediate lateral inhibition during epidermal patterning and are best characterized for their regulatory roles in trichome and root hair development. R3 MYBs act as negative regulators for trichome formation but as positive regulators for root hair development. In this article, we provide a comprehensive review on the role of R3 MYBs in the regulation of cell type specification in the model plant Arabidopsis. PMID:24782874

Regulation of Cell Fate Determination by Single-Repeat R3 MYB Transcription Factors in Arabidopsis

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

Wang, Shucai; Chen, Jay

2014-01-01

MYB transcription factors regulate multiple aspects of plant growth and development. Among the large family of MYB transcription factors, single-repeat R3 MYB are characterized by their short sequence (<120 amino acids) consisting largely of the single MYB DNA-binding repeat. In the model plant Arabidopsis, R3 MYBs mediate lateral inhibition during epidermal patterning and are best characterized for their regulatory roles in trichome and root hair development. R3 MYBs act as negative regulators for trichome formation but as positive regulators for root hair development. In this article, we provide a comprehensive review on the role of R3 MYBs in the regulationmore » of cell type specification in the model plant Arabidopsis.« less

Increasing colorectal cancer screening among individuals in the carpentry trade: test of risk communication interventions.

PubMed

Lipkus, Isaac M; Skinner, Celette Sugg; Dement, John; Pompeii, Lisa; Moser, Barry; Samsa, Gregory P; Ransohoff, David

2005-05-01

Individuals in the carpentry trade, due to lifestyle habits and occupational exposures, may be at above-average risk for colorectal cancer (CRC). Based on the literature which suggests that increasing perceived risk motivates behavior change, we report on the effectiveness of four risk-communication interventions targeted to increase initial, yearly and repeat fecal occult screening (FOBT) among carpenters (N = 860) over a 3-year period. Our 2 x 2 factorial design intervention study varied two dimensions of providing CRC risk factor information: (1) type of risk factor-one set of interventions emphasized three basic risk factors (age, family history and polyps); the other set emphasized a comprehensive set of risk factors including basic, lifestyle, and occupational factors, and (2) tailoring/not tailoring risk factor information. Participants were provided FOBTs. Outcomes were the proportion of returned FOBTs. Varying the amount and intensity of delivering CRC risk factors information affected neither risk perceptions nor initial, yearly, or repeat screening. However, yearly and repeat screening rates were greater among participants who received interventions addressing comprehensive set of risk factors, especially with increasing age. Tailoring on several CRC risk factors appears insufficient to increase and sustain elevated perceptions of CRC risks to promote screening.

Tuboimpedance: A New Test of Eustachian Tube Function.

PubMed

Smith, Matthew E; Zou, Charlie C; Blythe, Andrew J C; Tysome, James R

2017-04-01

Objective Eustachian tube (ET) dysfunction is most frequently caused by a failure of the ET to adequately open; however, there is currently no reliable method of assessing this. Tubomanometry has recently shown good interindividual repeatability as a measure of ET function by measuring middle ear pressure after the application of regulated nasopharyngeal pressures during swallowing. We present the first reports of a novel test: middle ear impedance measurements during standard nasopharyngeal pressure application (tuboimpedance). We assess repeatability in healthy ears and any advantages over tubomanometry. Study Design Exploratory cohort diagnosis study. Setting Tertiary referral center. Subjects Twenty screened, healthy ears (10 volunteers). Methods Tubomanometry and tuboimpedance tests were performed while individuals swallowed with applied nasopharyngeal pressures of 20, 30, 40, and 50 mbar. Eustachian tube opening detection rate and test repeatability (measured by intraclass correlation coefficient [ICC]) for immediate and delayed repeats at each pressure were compared. Results ET opening was detected more frequently using tuboimpedance, with a 100% detection rate using a nasopharyngeal pressure of 30 mbar or more, compared to 88% to 96% with tubomanometry. Detection of ET opening at 20 mbar was possible with tuboimpedance. Repeatability of both tests was mostly strong (ICC >0.7) for both immediate and delayed repeats. Repeatability for the tubomanometry R value was only fair to moderate. Conclusion Tuboimpedance may provide a repeatable measure of ET opening that is easier to perform due to lower nasopharyngeal pressures required and fewer issues with poor ear-probe sealing. Further assessment in patients with different forms of ET dysfunction is required.

Human Immunodeficiency Virus Tat-Activated Expression of Poliovirus Protein 2A Inhibits mRNA Translation

NASA Astrophysics Data System (ADS)

Sun, Xiao-Hong; Baltimore, David

1989-04-01

To study the effect of poliovirus protein 2A on cellular RNA translation, the tat control system of human immunodeficiency virus (HIV) was used. Protein 2A was expressed from a plasmid construct (pHIV/2A) incorporating the HIV long terminal repeat. Protein synthesis was measured by using chloramphenicol acetyltransferase as a reporter gene driven by the Rous sarcoma virus long terminal repeat. When HIV/2A was contransfected with the reporter, addition of a tat-producing plasmid caused at least a 50-fold drop in chloramphenicol acetyltransferase synthesis. A HeLa cell line carrying HIV/2A was established. In it, tat expression caused more than a 10-fold drop in chloramphenicol acetyltransferase synthesis from the reporter plasmid. Furthermore, 2A induction by tat caused cleavage of the cellular translation factor P220, a part of eukaryotic translation initiation factor 4F. Thus protein 2A can, by itself, carry out the inhibition of cellular protein synthesis characteristic of a poliovirus infection. Also, the HIV tat activation provides a very effective method to control gene expression in mammalian cells.

Repeatability of quantitative sensory testing in healthy cats in a clinical setting with comparison to cats with osteoarthritis.

PubMed

Addison, Elena S; Clements, Dylan N

2017-12-01

Objectives The aim of this study was to evaluate the repeatability of quantitative sensory tests (QSTs) in a group of healthy untrained cats (n = 14) and to compare the results with those from cats with osteoarthritis (n = 7). Methods Peak vertical force (PVF) and vertical impulse were measured on a pressure plate system. Thermal sensitivity was assessed using a temperature-controlled plate at 7°C and 40°C. Individual paw lifts and overall duration of paw lifts were counted and measured for each limb. Paw withdrawal thresholds were measured using manual and electronic von Frey monofilaments (MVF and EVF, respectively) applied to the metacarpal or metatarsal pads. All measurements were repeated twice to assess repeatability of the tests. Results In healthy cats all tests were moderately repeatable. When compared with cats with osteoarthritis the PVF was significantly higher in healthy hindlimbs in repeat 1 but not in repeat 2. Cats with osteoarthritis of the forelimbs showed a decrease in the frequency of paw lifts on the 7°C plate compared with cats with healthy forelimbs, and the duration of paw lifts was significantly less than healthy forelimbs in the first repeat but not in the second repeat. Osteoarthritic limbs had significantly lower paw withdrawal thresholds with both MVF and EVF than healthy limbs. Conclusions and relevance QSTs are moderately repeatable in untrained cats. Kinetic gait analysis did not permit differentiation between healthy limbs and those with osteoarthritis, but thermal sensitivity testing (cold) does. Sensory threshold testing can differentiate osteoarthritic and healthy limbs, and may be useful in the diagnosis and monitoring of this condition in cats in the clinical setting.

Inter- and intra-operator reliability and repeatability of shear wave elastography in the liver: a study in healthy volunteers.

PubMed

Hudson, John M; Milot, Laurent; Parry, Craig; Williams, Ross; Burns, Peter N

2013-06-01

This study assessed the reproducibility of shear wave elastography (SWE) in the liver of healthy volunteers. Intra- and inter-operator reliability and repeatability were quantified in three different liver segments in a sample of 15 subjects, scanned during four independent sessions (two scans on day 1, two scans 1 wk later) by two operators. A total of 1440 measurements were made. Reproducibility was assessed using the intra-class correlation coefficient (ICC) and a repeated measures analysis of variance. The shear wave speed was measured and used to estimate Young's modulus using the Supersonics Imagine Aixplorer. The median Young's modulus measured through the inter-costal space was 5.55 ± 0.74 kPa. The intra-operator reliability was better for same-day evaluations (ICC = 0.91) than the inter-operator reliability (ICC = 0.78). Intra-observer agreement decreased when scans were repeated on a different day. Inter-session repeatability was between 3.3% and 9.9% for intra-day repeated scans, compared with to 6.5%-12% for inter-day repeated scans. No significant difference was observed in subjects with a body mass index greater or less than 25 kg/m(2). Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Repeatability of Computerized Tomography-Based Anthropomorphic Measurements of Frailty in Patients With Pulmonary Fibrosis Undergoing Lung Transplantation.

PubMed

McClellan, Taylor; Allen, Brian C; Kappus, Matthew; Bhatti, Lubna; Dafalla, Randa A; Snyder, Laurie D; Bashir, Mustafa R

To determine interreader and intrareader repeatability and correlations among measurements of computerized tomography-based anthropomorphic measurements in patients with pulmonary fibrosis undergoing lung transplantation. This was an institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study of 23 randomly selected subjects (19 male and 4 female; median age = 69 years; range: 66-77 years) with idiopathic pulmonary fibrosis undergoing pulmonary transplantation, who had also undergone preoperative thoracoabdominal computerized tomography. Five readers of varying imaging experience independently performed the following cross-sectional area measurements at the inferior endplate of the L3 vertebral body: right and left psoas muscles, right and left paraspinal muscles, total abdominal musculature, and visceral and subcutaneous fat. The following measurements were obtained at the inferior endplate of T6: right and left paraspinal muscles with and without including the trapezius muscles and subcutaneous fat. Three readers repeated all measurements to assess intrareader repeatability. Intrareader repeatability was nearly perfect (interclass correlation coefficients = 0.99, P < 0.001). Interreader agreement was excellent across all 5 readers (interclass correlation coefficients: 0.71-0.99, P < 0.001). Coefficients of variance between measures ranged from 3.2%-6.8% for abdominal measurements, but were higher for thoracic measurements, up to 23.9%. Correlation between total paraspinal and total psoas muscle area was strong (r 2 = 0.67, P < 0.001). Thoracic and abdominal musculature had a weaker correlation (r 2 = 0.35-0.38, P < 0.001). Measures of thoracic and abdominal muscle and fat area are highly repeatable in patients with pulmonary fibrosis undergoing lung transplantation. Measures of muscle area are strongly correlated among abdominal locations, but inversely correlated between abdominal and thoracic locations. Copyright © 2017 Elsevier Inc. All rights reserved.

Reliability of real-time ultrasound measurement of transversus abdominis thickness in healthy trained subjects.

PubMed

Gnat, Rafael; Saulicz, Edward; Miądowicz, Barbara

2012-08-01

To investigate intra- and inter-rater reliability of the ultrasound measurement of transversus abdominis (TrA) thickness and thickness change (difference between thickness at rest and during contraction) in asymptomatic, trained subjects. To define the number of repeated measurements that provide acceptable level of reliability. To investigate variability of the measurements over time of 5 days and the reliability of duplicate analysis of images. A single-group repeated-measures design was used to assess reliability. Healthy volunteers (n = 10) were subjected to 1-week training in voluntary activation of TrA. Real-time ultrasound imaging and subsequent measurement of the TrA thickness at rest and during voluntary contraction were repeated on Monday, Wednesday and Friday of the next week. Using a single repeated measurement, intraclass correlation coefficients (ICCs) for TrA thickness were: 0.86-0.95 (intra-rater), 0.86-0.92 (inter-rater); and for TrA thickness change: 0.34-0.56 (intra-rater), 0.47-0.61 (inter-rater). Using the mean of three repeated measurements respective values were: 0.97, 0.96-0.98; and 0.81-0.84, 0.80-0.90. No significant differences were found between mean values of TrA thickness as well as thickness change obtained on three consecutive measurement days. Duplicate analysis of the images was highly reliable with ICCs of 0.89-0.99. Two repeated measurements for TrA thickness and at least three measurements for TrA thickness change are needed to achieve acceptable levels of intra- and inter-rater reliability. In healthy trained volunteers TrA thickness and thickness change are relatively stable parameters over a 5-day period. Duplicate analysis of the same images by two blinded observers is reliable.

Measuring environmental change in forest ecosystems by repeated soil sampling: A North American perspective

Treesearch

Gregory B. Lawrence; Ivan J. Fernandez; Daniel D. Richter; Donald S. Ross; Paul W. Hazlett; Scott W. Bailey; Rock Ouimet; Richard A. F. Warby; Arthur H. Johnson; Henry Lin; James M. Kaste; Andrew G. Lapenis; Timothy J. Sullivan

2013-01-01

Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest...

Variables Associated with Repeated Suicide Attempt in a Criminal Justice Population

ERIC Educational Resources Information Center

Hakansson, Anders; Bradvik, Louise; Schlyter, Frans; Berglund, Mats

2011-01-01

The aim of this study was to identify factors associated with repeated suicide attempts among criminal justice clients examined for substance abuse using the Addiction Severity Index. Among suicide attempters (n = 1,404), repeaters (two or more attempts, n = 770) were compared to nonrepeaters. In logistic regression, repetition was associated with…

Comparing Measurement Error between Two Different Methods of Measurement of Various Magnitudes

ERIC Educational Resources Information Center

Zavorsky, Gerald S.

2010-01-01

Measurement error is a common problem in several fields of research such as medicine, physiology, and exercise science. The standard deviation of repeated measurements on the same person is the measurement error. One way of presenting measurement error is called the repeatability, which is 2.77 multiplied by the within subject standard deviation.…

Impact of the telephone assistive device (TAD) on stuttering severity while speaking on the telephone.

PubMed

Chambers, Nola

2009-01-01

There is extensive experimental evidence that altered auditory feedback (AAF) can have a clinically significant effect on the severity of speech symptoms in people who stutter. However, there is less evidence regarding whether these experimental effects can be observed in naturalistic everyday settings particularly when using the telephone. This study aimed to investigate the effectiveness of the Telephone Assistive Device (TAD), which is designed to provide AAF on the telephone to people who stutter, on reducing stuttering severity. Nine adults participated in a quasi-experimental study. Stuttering severity was measured first without and then with the device in participants' naturalistic settings while making and receiving telephone calls (immediate benefit). Participants were then allowed a week of repeated use of the device following which all measurements were repeated (delayed benefit). Overall, results revealed significant immediate benefits from the TAD in all call conditions. Delayed benefits in received and total calls were also significant. There was substantial individual variability in response to the TAD but none of the demographic or speech-related factors measured in the study were found to significantly impact the benefit (immediate or delayed) derived from the TAD. Results have implications for clinical decision making for adults who stutter.

Fluctuating asymmetry in broiler chickens: a decision protocol for trait selection in seven measuring methods.

PubMed

Van Nuffel, A; Tuyttens, F A M; Van Dongen, S; Talloen, W; Van Poucke, E; Sonck, B; Lens, L

2007-12-01

Nonidentical development of bilateral traits due to disturbing genetic or developmental factors is called fluctuating asymmetry (FA) if such deviations are continuously distributed. Fluctuating asymmetry is believed to be a reliable indicator of the fitness and welfare of an animal. Despite an increasing body of research, the link between FA and animal performance or welfare is reported to be inconsistent, possibly, among other reasons, due to inaccurate measuring protocols or incorrect statistical analyses. This paper reviews problems of interpreting FA results in poultry and provides guidelines for the measurement and analysis of FA, applied to broilers. A wide range of morphological traits were measured by 7 different techniques (ranging from measurements on living broilers or intact carcasses to X-rays, bones, and digital images) and evaluated for their applicability to estimate FA. Following 4 selection criteria (significant FA, absence of directional asymmetry or antisymmetry, absence of between-trait correlation in signed FA values, and high signal-to-noise ratio), from 3 to 14 measurements per method were found suitable for estimating the degree of FA. The accuracy of FA estimates was positively related to the complexity and time investment of the measuring method. In addition, our study clearly shows the importance of securing adequate statistical power when designing FA studies. Repeatability analyses of FA estimates indicated the need for larger sample sizes, more repeated measurements, or both, than are commonly used in FA studies.

Clinical and Psychosocial Profiles of Asian Immigrants Who Repeatedly Attempt Suicide: A Mixed-Method Study of Risk and Protective Factors.

PubMed

Chung, Irene W; Caine, Eric D; Barron, Charles T; Badaracco, Mary A

2015-01-01

Persons who repeatedly attempt suicide comprise a highly distressed population that warrants the understanding of risk and protective factors in assessment and treatment. There is a dearth of literature on Asian immigrants' suicidal behavior. The study aimed to capture the clinical and psychosocial profiles of Asian immigrants who made repeated suicide attempts. We utilized retrospective chart reviews (n = 44) and in-person interviews (n = 12) in two urban public hospitals. The study samples shared major suicide risk factors identified in studies of other populations. Participants of the interview sample suffered from a pervasive sense of hopelessness stemming from social isolation, self-stigma, feelings of failure in their life roles, and perceptions of rejection by their families. Conversely, psychological well-being--feeling cared for and able to reciprocate care for others--appeared to be a protective factor for participants who improved in their functioning and recovery. The study lays the groundwork for further research on suicide risk and protective factors.

Effect of Repeat Copy Number on Variable-Number Tandem Repeat Mutations in Escherichia coli O157:H7

PubMed Central

Vogler, Amy J.; Keys, Christine; Nemoto, Yoshimi; Colman, Rebecca E.; Jay, Zack; Keim, Paul

2006-01-01

Variable-number tandem repeat (VNTR) loci have shown a remarkable ability to discriminate among isolates of the recently emerged clonal pathogen Escherichia coli O157:H7, making them a very useful molecular epidemiological tool. However, little is known about the rates at which these sequences mutate, the factors that affect mutation rates, or the mechanisms by which mutations occur at these loci. Here, we measure mutation rates for 28 VNTR loci and investigate the effects of repeat copy number and mismatch repair on mutation rate using in vitro-generated populations for 10 E. coli O157:H7 strains. We find single-locus rates as high as 7.0 × 10−4 mutations/generation and a combined 28-locus rate of 6.4 × 10−4 mutations/generation. We observed single- and multirepeat mutations that were consistent with a slipped-strand mispairing mutation model, as well as a smaller number of large repeat copy number mutations that were consistent with recombination-mediated events. Repeat copy number within an array was strongly correlated with mutation rate both at the most mutable locus, O157-10 (r2 = 0.565, P = 0.0196), and across all mutating loci. The combined locus model was significant whether locus O157-10 was included (r2 = 0.833, P < 0.0001) or excluded (r2 = 0.452, P < 0.0001) from the analysis. Deficient mismatch repair did not affect mutation rate at any of the 28 VNTRs with repeat unit sizes of >5 bp, although a poly(G) homomeric tract was destabilized in the mutS strain. Finally, we describe a general model for VNTR mutations that encompasses insertions and deletions, single- and multiple-repeat mutations, and their relative frequencies based upon our empirical mutation rate data. PMID:16740932

Pattern of psychiatric morbidity among theft offenders remanded or referred for psychiatric evaluation and factors associated with reoffence.

PubMed

Chan, Lai Gwen; Bharat, Saluja; Dani, Dhaval Kirti

2013-06-01

In Singapore, theft and related crimes constitute more than 50% of all reported crime, and are the most common offences committed by accused persons remanded to the Institute of Mental Health (IMH), Singapore. There is a need for better understanding of the forensic psychiatric aspects of such offenders. This study aimed to determine the prevalence of psychiatric disorders among theft offenders remanded or referred for forensic assessment in 2010, compare the differences between first-time and repeat theft offenders, and identify the factors associated with reoffence. Forensic evaluations of inpatient and outpatient theft offenders that were conducted at IMH in the year 2010 were retrieved and reviewed. The sociodemographic and clinical data of first-time and repeat theft offenders were collected and compared using Student's t-test and chi-square test for continuous and categorical variables, respectively. Multivariate regression was used to identify the factors that were predictive of repeat offence. Overall, 10% of offenders had no mental illness. Substance use disorders, mood disorders and psychotic disorders were the most common diagnoses. Psychotic disorders were significantly less common in repeat offenders. Repeat offenders also tended to have a history of conduct problems in childhood. Noncompliance with psychiatric treatment was positively associated with repeat offence, while psychotic disorders were negatively associated. The pattern of psychiatric morbidity among theft offenders in Singapore has changed over the last ten years. Kleptomania remains rare. Significant differences between first-time and repeat offenders have implications on the treatment, follow-up and rehabilitation of theft offenders in Singapore.

Repeatability Modeling for Wind-Tunnel Measurements: Results for Three Langley Facilities

NASA Technical Reports Server (NTRS)

Hemsch, Michael J.; Houlden, Heather P.

2014-01-01

Data from extensive check standard tests of seven measurement processes in three NASA Langley Research Center wind tunnels are statistically analyzed to test a simple model previously presented in 2000 for characterizing short-term, within-test and across-test repeatability. The analysis is intended to support process improvement and development of uncertainty models for the measurements. The analysis suggests that the repeatability can be estimated adequately as a function of only the test section dynamic pressure over a two-orders- of-magnitude dynamic pressure range. As expected for low instrument loading, short-term coefficient repeatability is determined by the resolution of the instrument alone (air off). However, as previously pointed out, for the highest dynamic pressure range the coefficient repeatability appears to be independent of dynamic pressure, thus presenting a lower floor for the standard deviation for all three time frames. The simple repeatability model is shown to be adequate for all of the cases presented and for all three time frames.

Effects of metacognitive instruction on the academic achievement of students in the secondary sciences

NASA Astrophysics Data System (ADS)

Bianchi, Gregory A.

The purpose of this study was to investigate the effects of reflective assessment in the form of situated metacognitive prompts on student achievement in the secondary sciences. A second goal was to determine whether specific gender differences existed in terms of student responsiveness to the metacognitive interventions. Participants in the study consisted of a convenience sample from a population of ninth-grade honors biology students in a large suburban school district located near Seattle, Washington. Beyond answering the specific research questions raised in this study, an additional aim was to broaden the growing body of research pertaining to the effect of metacognition on student achievement. A quasi-experimental, non-equivalent control group design was employed in this study. Descriptive and inferential statistics were computed to address the specific research questions raised. Specifically, a three-way repeated-measures ANOVA was performed. For this purpose, a single within-subjects factor, termed Testing, was defined. Three levels were allocated to this factor, and quantitative data from the Pretest, Posttest, and Retention Test were assigned to the levels, respectively. Group and Gender were defined as between-subjects factors, and both were allocated two levels; the two Group levels were Reflective and Non-Reflective. The effects of Group and Gender on each of the three quantitative measures were examined singly and in interaction with each other. Tests of statistical significance were analyzed at the .05 level. There was a statistically significant effect for Group (Reflective, Non-Reflective) by Testing (Pretest, Posttest, Retention Test). A three-way repeated-measures ANOVA procedure revealed that students in the Reflective group outperformed students in the Non-Reflective group (F = 10.258, p = .002, Partial eta 2 = .088). According to the effect size estimate, almost 9% of variance in the Testing variable was attributable to the Group variable. There was not a significant interaction effect for Gender. A three-way repeated-measures ANOVA procedure revealed that Testing X Group X Gender did not yield a statistically significant F ratio (F = 1.471, p = .228, Partial eta2 = .014). Students in the Reflective group outperformed students in the Non-Reflective group, regardless of gender. The findings of this study offer modest evidence that reflective assessment in the form of situated metacognitive prompts may improve student academic outcomes at the secondary level. This study failed to provide a significant finding regarding gender-related variation in a metacognitive learning cycle.

Comparing Dynamic Treatment Regimes Using Repeated-Measures Outcomes: Modeling Considerations in SMART Studies

PubMed Central

Lu, Xi; Nahum-Shani, Inbal; Kasari, Connie; Lynch, Kevin G.; Oslin, David W.; Pelham, William E.; Fabiano, Gregory; Almirall, Daniel

2016-01-01

A dynamic treatment regime (DTR) is a sequence of decision rules, each of which recommends a treatment based on a patient’s past and current health status. Sequential, multiple assignment, randomized trials (SMARTs) are multi-stage trial designs that yield data specifically for building effective DTRs. Modeling the marginal mean trajectories of a repeated-measures outcome arising from a SMART presents challenges, because traditional longitudinal models used for randomized clinical trials do not take into account the unique design features of SMART. We discuss modeling considerations for various forms of SMART designs, emphasizing the importance of considering the timing of repeated measures in relation to the treatment stages in a SMART. For illustration, we use data from three SMART case studies with increasing level of complexity, in autism, child attention deficit hyperactivity disorder (ADHD), and adult alcoholism. In all three SMARTs we illustrate how to accommodate the design features along with the timing of the repeated measures when comparing DTRs based on mean trajectories of the repeated-measures outcome. PMID:26638988

Comparing dynamic treatment regimes using repeated-measures outcomes: modeling considerations in SMART studies.

PubMed

Lu, Xi; Nahum-Shani, Inbal; Kasari, Connie; Lynch, Kevin G; Oslin, David W; Pelham, William E; Fabiano, Gregory; Almirall, Daniel

2016-05-10

A dynamic treatment regime (DTR) is a sequence of decision rules, each of which recommends a treatment based on a patient's past and current health status. Sequential, multiple assignment, randomized trials (SMARTs) are multi-stage trial designs that yield data specifically for building effective DTRs. Modeling the marginal mean trajectories of a repeated-measures outcome arising from a SMART presents challenges, because traditional longitudinal models used for randomized clinical trials do not take into account the unique design features of SMART. We discuss modeling considerations for various forms of SMART designs, emphasizing the importance of considering the timing of repeated measures in relation to the treatment stages in a SMART. For illustration, we use data from three SMART case studies with increasing level of complexity, in autism, child attention deficit hyperactivity disorder, and adult alcoholism. In all three SMARTs, we illustrate how to accommodate the design features along with the timing of the repeated measures when comparing DTRs based on mean trajectories of the repeated-measures outcome. Copyright © 2015 John Wiley & Sons, Ltd.

Effects of Expressive Writing Effects on Disgust and Anxiety in a Subsequent Dissection

NASA Astrophysics Data System (ADS)

Randler, Christoph; Wüst-Ackermann, Peter; im Kampe, Viola Otte; Meyer-Ahrens, Inga H.; Tempel, Benjamin J.; Vollmer, Christian

2015-10-01

Emotions influence motivation and achievement, but negative emotions have rarely been assessed in science education. In this study, we assessed the influence of two different expressive writing assignments on disgust and anxiety in university students prior to the dissection of a trout. We randomly assigned students to one of two expressive writing tasks and measured specific state disgust and state anxiety after writing and after the dissection. Specific state disgust was measured a third time after 3 weeks. One writing task was concerned with the dissection, and the other was related to behavioral experiments with mice. We used two general linear models with repeated measures. In the first model, specific state disgust (pre, post, and follow-up) was used as the dependent repeated measure and experimental group as the independent variable. In the second model, state anxiety was used as the dependent repeated measure (pre, post) with experimental group as the independent variable. The repeated testing showed a highly significant effect of experimental group on the repeated measures of disgust. Writing about worries and emotions concerning the dissection leads to higher disgust scores compared to writing about mice. These higher scores persisted even 3 weeks later in the follow-up test. Concerning anxiety, there was a clear influence of the repeated measure of state anxiety, but anxiety was not influenced by the experimental group. We suggest that positive writing should be used in educational contexts to reduce disgust.

A Deluge of Complex Repeats: The Solanum Genome

PubMed Central

Mehra, Mrigaya; Gangwar, Indu; Shankar, Ravi

2015-01-01

Repetitive elements have lately emerged as key components of genome, performing varieties of roles. It has now become necessary to have an account of repeats for every genome to understand its dynamics and state. Recently, genomes of two major Solanaceae species, Solanum tuberosum and Solanum lycopersicum, were sequenced. These species are important crops having high commercial significance as well as value as model species. However, there is a reasonable gap in information about repetitive elements and their possible roles in genome regulation for these species. The present study was aimed at detailed identification and characterization of complex repetitive elements in these genomes, along with study of their possible functional associations as well as to assess possible transcriptionally active repetitive elements. In this study, it was found that ~50–60% of genomes of S. tuberosum and S. lycopersicum were composed of repetitive elements. It was also found that complex repetitive elements were associated with >95% of genes in both species. These two genomes are mostly composed of LTR retrotransposons. Two novel repeat families very similar to LTR/ERV1 and LINE/RTE-BovB have been reported for the first time. Active existence of complex repeats was estimated by measuring their transcriptional abundance using Next Generation Sequencing read data and Microarray platforms. A reasonable amount of regulatory components like transcription factor binding sites and miRNAs appear to be under the influence of these complex repetitive elements in these species, while several genes appeared to possess exonized repeats. PMID:26241045

Stability, reliability and cross-mode correlations of tests in a recommended 8-minute performance assessment battery

NASA Technical Reports Server (NTRS)

Wilkes, R. L.; Kennedy, R. S.; Dunlap, W. P.; Lane, N. E.

1986-01-01

A need exists for an automated performance test system to study drugs, agents, treatments, and stresses of interest to the aviation, space, and environmental medical community. The purpose of this present study is to evaluate tests for inclusion in the NASA-sponsored Automated Performance Test System (APTS). Twenty-one subjects were tested over 10 replications with tests previously identified as good candidates for repeated-measure research. The tests were concurrently administered in paper-and-pencil and microcomputer modes. Performance scores for the two modes were compared. Data from trials 1 to 10 were examined for indications of test stability and reliability. Nine of the ten APT system tests achieved stability. Reliabilities were generally high. Cross-correlation of microbased tests with traditional paper-and-pencil versions revealed similarity of content within tests in the different modes, and implied at least three cognition and two motor factors. This protable, inexpensive, rugged, computerized battery of tests is recommended for use in repeated-measures studies of environmental and drug effects on performance. Identification of other tests compatible with microcomputer testing and potentially capable of tapping previously unidentified factors is recommended. Documentation of APTS sensitivity to environmental agents is available for more than a dozen facilities and is reported briefly. Continuation of such validation remains critical in establishing the efficacy of APTS tests.

The Queensland study of Melanoma: Environmental and Genetic Associations (Q-MEGA). Study design, baseline characteristics, and repeatability of phenotype and sun exposure measures

PubMed Central

Baxter, Amanda J.; Hughes, Maria Celia; Kvaskoff, Marina; Siskind, Victor; Shekar, Sri; Aitken, Joanne F.; Green, Adele C.; Duffy, David L.; Hayward, Nicholas K.; Martin, Nicholas G.; Whiteman, David C.

2013-01-01

Cutaneous malignant melanoma (CMM) is a major health issue in Queensland, Australia which has the world’s highest incidence. Recent molecular and epidemiologic studies suggest that CMM arises through multiple etiological pathways involving gene-environment interactions. Understanding the potential mechanisms leading to CMM requires larger studies than those previously conducted. This article describes the design and baseline characteristics of Q-MEGA, the Queensland study of Melanoma: Environmental and Genetic Associations, which followed-up four population-based samples of CMM patients in Queensland, including children, adolescents, men aged over 50, and a large sample of adult cases and their families, including twins. Q-MEGA aims to investigate the roles of genetic and environmental factors, and their interaction, in the etiology of melanoma. 3,471 participants took part in the follow-up study and were administered a computer-assisted telephone interview in 2002–2005. Updated data on environmental and phenotypic risk factors, and 2,777 blood samples were collected from interviewed participants as well as a subset of relatives. This study provides a large and well-described population-based sample of CMM cases with follow-up data. Characteristics of the cases and repeatability of sun exposure and phenotype measures between the baseline and the follow-up surveys, from six to 17 years later, are also described. PMID:18361720

Does Dry Eye Affect Repeatability of Corneal Topography Measurements?

PubMed

Doğan, Aysun Şanal; Gürdal, Canan; Köylü, Mehmet Talay

2018-04-01

The purpose of this study was to assess the repeatability of corneal topography measurements in dry eye patients and healthy controls. Participants underwent consecutive corneal topography measurements (Sirius; Costruzione Strumenti Oftalmici, Florence, Italy). Two images with acquisition quality higher than 90% were accepted. The following parameters were evaluated: minimum and central corneal thickness, aqueous depth, apex curvature, anterior chamber volume, horizontal anterior chamber diameter, iridocorneal angle, cornea volume, and average simulated keratometry. Repeatability was assessed by calculating intra-class correlation coefficient. Thirty-three patients with dry eye syndrome and 40 healthy controls were enrolled to the study. The groups were similar in terms of age (39 [18-65] vs. 30.5 [18-65] years, p=0.198) and gender (M/F: 4/29 vs. 8/32, p=0.366). Intra-class correlation coefficients among all topography parameters within both groups showed excellent repeatability (>0.90). The anterior segment measurements provided by the Sirius corneal topography system were highly repeatable for dry eye patients and are sufficiently reliable for clinical practice and research.

Effects of time and sampling location on concentrations of β-hydroxybutyric acid in dairy cows.

PubMed

Mahrt, A; Burfeind, O; Heuwieser, W

2014-01-01

Two trials were conducted to examine factors potentially influencing the measurement of blood β-hydroxybutyric acid (BHBA) in dairy cows. The objective of the first trial was to study effects of sampling time on BHBA concentration in continuously fed dairy cows. Furthermore, we determined test characteristics of a single BHBA measurement at a random time of the day to diagnose subclinical ketosis considering commonly used cut-points (1.2 and 1.4 mmol/L). Finally, we set out to evaluate if test characteristics could be enhanced by repeating measurements after different time intervals. During 4 herd visits, a total of 128 cows (8 to 28 d in milk) fed 10 times daily were screened at 0900 h and preselected by BHBA concentration. Blood samples were drawn from the tail vessels and BHBA concentrations were measured using an electronic BHBA meter (Precision Xceed, Abbott Diabetes Care Ltd., Witney, UK). Cows with BHBA concentrations ≥0.8 mmol/L at this time were enrolled in the trial (n=92). Subsequent BHBA measurements took place every 3h for a total of 8 measurements during 24 h. The effect of sampling time on BHBA concentrations was tested in a repeated-measures ANOVA repeating sampling time. Sampling time did not affect BHBA concentrations in continuously fed dairy cows. Defining the average daily BHBA concentration calculated from the 8 measurements as the gold standard, a single measurement at a random time of the day to diagnose subclinical ketosis had a sensitivity of 0.90 or 0.89 at the 2 BHBA cut-points (1.2 and 1.4 mmol/L). Specificity was 0.88 or 0.90 using the same cut-points. Repeating measurements after different time intervals improved test characteristics only slightly. In the second experiment, we compared BHBA concentrations of samples drawn from 3 different blood sampling locations (tail vessels, jugular vein, and mammary vein) of 116 lactating dairy cows. Concentrations of BHBA differed in samples from the 3 sampling locations. Mean BHBA concentration was 0.3 mmol/L lower when measured in the mammary vein compared with the jugular vein and 0.4 mmol/L lower in the mammary vein compared with the tail vessels. We conclude that to measure BHBA, blood samples of continuously fed dairy cows can be drawn at any time of the day. A single measurement provides very good test characteristics for on-farm conditions. Blood samples for BHBA measurement should be drawn from the jugular vein or tail vessels; the mammary vein should not be used for this purpose. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Changes in importance of work and vocational satisfaction during the 2 years after breast cancer surgery and factors associated with this.

PubMed

Nilsson, Marie I; Saboonchi, Fredrik; Alexanderson, Kristina; Olsson, Mariann; Wennman-Larsen, Agneta; Petersson, Lena-Marie

2016-06-01

The purpose of this study is to investigate how women, during the 2 years following breast cancer surgery, rate importance of work and vocational satisfaction, and baseline factors associated with rating over time. A prospective cohort study of 692 women aged 20-63 included about 4 weeks after a first breast cancer surgery. Register data on treatment and data from six repeated questionnaires during a 2-year follow-up (at baseline, 4, 8, 12, 18, 24 months) were used in two-way mixed repeated analysis of variance and mixed repeated measures analysis of covariance. The women rated importance of work (m = 3.74; sd 0.88) (maximum 5) and vocational satisfaction (m = 4.30; sd 1.38) (maximum 6) high during the 2 years. Women with planned chemotherapy rated lower vocational satisfaction and especially so at 4 months after inclusion (F 1, 498 = 8.20; p = 0.004). Higher age, better physical, and mental/social work ability at baseline influenced rating of vocational satisfaction. Supportive colleagues was an important covariate that significantly affected ratings of importance of work as well as vocational satisfaction, i.e., women with better support rated on average higher on these outcomes. The effect of chemotherapy disappeared after including the abovementioned baseline covariates. Women diagnosed with breast cancer in the following 2 years rate importance of work and vocational satisfaction high, which are associated to lower work ability and social support. Work is a very important aspect in life also after a cancer diagnosis, which has to be acknowledged when discussing treatment and rehabilitation plans with women with breast cancer. Furthermore, workplace support needs to be assessed as this is an influential factor.

A cohort evaluation on arterial stiffness and hypertensive disorders in pregnancy.

PubMed

Lim, Wai Yee; Saw, Seang Mei; Tan, Kok Hian; Yeo, George S H; Kwek, Kenneth Y C

2012-12-26

Hypertensive disorders in pregnancy are associated with systemic endothelial dysfunction leading to impaired physiological vasodilation. Recent evidence has shown central aortic pressures obtained through pulse wave analysis, at less than 14 weeks of gestation, to be predictive of pre-eclampsia. In light of this, we aimed to evaluate the role of central aortic stiffness in the prediction and discrimination of hypertensive disorders in pregnancy. A cohort study of women with viable, singleton pregnancies at less than 14 weeks of amenorrhoea, and without multiple pregnancies, autoimmune or renal disease, diagnosed with aneuploidy or fetal anomaly will be recruited from a single maternity hospital and followed up till delivery and puerperium. A targeted sample size of 1000 eligible pregnant women will be enrolled into the study from antenatal clinics. Main exposure under study is central aortic pulse pressure using radial pulse wave recording, and the outcomes under follow-up are gestational hypertension and pre-eclampsia. Other measures include lifestyle factors such as smoking, physical exercise, psychometric evaluations, vasoactive factors, uterine artery pulsatility index, height and weight measurements. These measures will be repeated over 4 antenatal visits at 11-14, 18-22, 28-32 and above 34 weeks of gestation. Double data entry will be performed on Microsoft Access, and analysis of data will include the use of random effect models and receiver operating characteristic curves on Stata 11.2. The proposed study design will enable a longitudinal evaluation of the central aortic pressure changes as a marker for vascular compliance during pregnancy. As measures are repeated over time, the timing and severity of changes are detectable, and findings may yield important information on how aberrant vascular responses occur and its role in the early detection and prediction of hypertensive disorders.

Study design and methodology for a multicentre, randomised controlled trial of transcranial direct current stimulation as a treatment for unipolar and bipolar depression.

PubMed

Alonzo, Angelo; Aaronson, Scott; Bikson, Marom; Husain, Mustafa; Lisanby, Sarah; Martin, Donel; McClintock, Shawn M; McDonald, William M; O'Reardon, John; Esmailpoor, Zeinab; Loo, Colleen

2016-11-01

Transcranial Direct Current Stimulation (tDCS) is a new, non-invasive neuromodulation approach for treating depression that has shown promising efficacy. The aim of this trial was to conduct the first international, multicentre randomised controlled trial of tDCS as a treatment for unipolar and bipolar depression. The study recruited 120 participants across 6 sites in the USA and Australia. Participants received active or sham tDCS (2.5mA, 20 sessions of 30min duration over 4weeks), followed by a 4-week open label active treatment phase and a 4-week taper phase. Mood and neuropsychological outcomes were assessed with the primary antidepressant outcome measure being the Montgomery-Asberg Depression Rating Scale (MADRS). A neuropsychological battery was administered to assess safety and examine cognitive effects. The study also investigated the possible influence of genetic polymorphisms on outcomes. The trial was triple-blinded. Participants, tDCS treaters and study raters were blinded to each participant's tDCS group allocation in the sham-controlled phase. Specific aspects of tDCS administration, device operation and group allocation were designed to optimise the integrity of blinding. Outcome measures will be tested using a mixed effects repeated measures analysis with the primary factors being Time as a repeated measure, tDCS condition (sham or active) and Diagnosis (unipolar or bipolar). A restricted number of random and fixed factors will be included as required to account for extraneous differences. As a promising treatment, tDCS has excellent potential for translation into widespread clinical use, being cost effective, portable, easy to operate and well tolerated. Copyright © 2016 Elsevier Inc. All rights reserved.

When being narrow minded is a good thing: locally biased people show stronger contextual cueing.

PubMed

Bellaera, Lauren; von Mühlenen, Adrian; Watson, Derrick G

2014-01-01

Repeated contexts allow us to find relevant information more easily. Learning such contexts has been proposed to depend upon either global processing of the repeated contexts, or alternatively processing of the local region surrounding the target information. In this study, we measured the extent to which observers were by default biased to process towards a more global or local level. The findings showed that the ability to use context to help guide their search was strongly related to an observer's local/global processing bias. Locally biased people could use context to help improve their search better than globally biased people. The results suggest that the extent to which context can be used depends crucially on the observer's attentional bias and thus also to factors and influences that can change this bias.

Psychophysiological responses to auditory change.

PubMed

Chuen, Lorraine; Sears, David; McAdams, Stephen

2016-06-01

A comprehensive characterization of autonomic and somatic responding within the auditory domain is currently lacking. We studied whether simple types of auditory change that occur frequently during music listening could elicit measurable changes in heart rate, skin conductance, respiration rate, and facial motor activity. Participants heard a rhythmically isochronous sequence consisting of a repeated standard tone, followed by a repeated target tone that changed in pitch, timbre, duration, intensity, or tempo, or that deviated momentarily from rhythmic isochrony. Changes in all parameters produced increases in heart rate. Skin conductance response magnitude was affected by changes in timbre, intensity, and tempo. Respiratory rate was sensitive to deviations from isochrony. Our findings suggest that music researchers interpreting physiological responses as emotional indices should consider acoustic factors that may influence physiology in the absence of induced emotions. © 2016 Society for Psychophysiological Research.

[Latex allergy in a paediatric hospital. Characteristics and risk factors].

PubMed

Bailey, Michael; Norambuena, Ximena; Roizen, Gigia; Rodríguez, Jorge; Quezada, Arnoldo

The prevalence of latex sensitisation varies according to the population studied. There are various risk factors that increase latex sensitisation, such as genetic risk, atopy, and multiple surgeries. To characterise patients referred to an Immunology Unit with suspected latex allergy, and to analyse their clinical features and risk factors. A retrospective, descriptive study was conducted on children suspected of latex allergy. Their medical records were reviewed in order to assess symptoms with contact or exposure to latex materials. Known risk factors to latex sensitisation, such as pathologies requiring repeated surgery (spina bifida, myelomeningocele, scoliosis and nephro-urological alterations), atopy (rhinitis, asthma, atopic dermatitis) were investigated. A prick test and/or specific IgE to latex were also performed. A multivariate logistic regression model was performed to find associations between symptoms triggered by exposure to latex with underlying diseases and other risk conditions. A total of 106 patients were enrolled in the study, of whom 50 were evaluable. At diagnosis 96% of patients were older than five years. Most of the risk factors described were observable in these patients, such as multiple surgeries, neurological and nephro-urological malformations, surgery before one year-old, and repeated bladder catheterisation. After latex exposure, mucous cutaneous manifestations were the most common (52%), followed by respiratory symptoms (36%). All patients were sensitised and allergic to latex. Latex allergy is a significant problem in children with risk factors. The results shown in this study raise important challenges for preventive measures and awareness. Copyright © 2016 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Duration of in vivo endotoxin tolerance in horses.

PubMed

Holcombe, Susan J; Jacobs, Carrie C; Cook, Vanessa L; Gandy, Jeffery C; Hauptman, Joseph G; Sordillo, Lorraine M

2016-05-01

Endotoxemia models are used to study mechanisms and treatments of early sepsis. Repeated endotoxin exposures induce periods of endotoxin tolerance, characterized by diminished proinflammatory responses to lipopolysaccharide (LPS) and modulated production of proinflammatory cytokines. Repeated measure designs using equine endotoxemia models are rarely performed, despite the advantages associated with reduced variability, because the altered responsiveness would confound study results and because the duration of equine endotoxin tolerance is unknown. We determined the interval of endotoxin tolerance, in vivo, in horses based on physical, clinicopathologic, and proinflammatory gene expression responses to repeated endotoxin exposures. Six horses received 30 ng/kg LPS in saline infused over 30 min. Behavior pain scores, physical examination parameters, and blood for complete blood count and proinflammatory gene expression were obtained at predetermined intervals for 24h. Horses received a total of 3 endotoxin exposures. The first exposure was LPS 1, followed 7 days later by LPS 7 or 14-21 days later by LPS 14-21. Lipopolysaccharide exposures were allocated in a randomized, crossover design. Lipopolysaccharide produced clinical and clinicopathologic signs of endotoxemia and increased expression of tumor necrosis factor alpha (TNFα), interleukin (IL)-6 and IL-8, P<0.001. Horses exhibited evidence of endotoxin tolerance following LPS 7 but not following LPS 14-21. Horses had significantly lower pain scores, heart rates, respiratory rates and duration of fever, after LPS 7 compared to LPS 1 and LPS 14-21, P<0.001, and expression of TNFα was lower in the whole blood of horses after LPS 7, P=0.05. Clinical parameters and TNFα gene expression were similar or slightly increased in horses following LPS 14-21 compared to measurements made in horses following LPS 1, suggesting that endotoxin tolerance had subsided. A minimum of 3 weeks between experiments is warranted if repeated measures designs are used to assess in vivo response to endotoxin in horses. Copyright © 2016 Elsevier B.V. All rights reserved.

Validation of a 3D CT method for measurement of linear wear of acetabular cups.

PubMed

Jedenmalm, Anneli; Nilsson, Fritjof; Noz, Marilyn E; Green, Douglas D; Gedde, Ulf W; Clarke, Ian C; Stark, Andreas; Maguire, Gerald Q; Zeleznik, Michael P; Olivecrona, Henrik

2011-02-01

We evaluated the accuracy and repeatability of a 3D method for polyethylene acetabular cup wear measurements using computed tomography (CT). We propose that the method be used for clinical in vivo assessment of wear in acetabular cups. Ultra-high molecular weight polyethylene cups with a titanium mesh molded on the outside were subjected to wear using a hip simulator. Before and after wear, they were (1) imaged with a CT scanner using a phantom model device, (2) measured using a coordinate measurement machine (CMM), and (3) weighed. CMM was used as the reference method for measurement of femoral head penetration into the cup and for comparison with CT, and gravimetric measurements were used as a reference for both CT and CMM. Femoral head penetration and wear vector angle were studied. The head diameters were also measured with both CMM and CT. The repeatability of the method proposed was evaluated with two repeated measurements using different positions of the phantom in the CT scanner. The accuracy of the 3D CT method for evaluation of linear wear was 0.51 mm and the repeatability was 0.39 mm. Repeatability for wear vector angle was 17°. This study of metal-meshed hip-simulated acetabular cups shows that CT has the capacity for reliable measurement of linear wear of acetabular cups at a clinically relevant level of accuracy.

Latent variable models for gene-environment interactions in longitudinal studies with multiple correlated exposures.

PubMed

Tao, Yebin; Sánchez, Brisa N; Mukherjee, Bhramar

2015-03-30

Many existing cohort studies designed to investigate health effects of environmental exposures also collect data on genetic markers. The Early Life Exposures in Mexico to Environmental Toxicants project, for instance, has been genotyping single nucleotide polymorphisms on candidate genes involved in mental and nutrient metabolism and also in potentially shared metabolic pathways with the environmental exposures. Given the longitudinal nature of these cohort studies, rich exposure and outcome data are available to address novel questions regarding gene-environment interaction (G × E). Latent variable (LV) models have been effectively used for dimension reduction, helping with multiple testing and multicollinearity issues in the presence of correlated multivariate exposures and outcomes. In this paper, we first propose a modeling strategy, based on LV models, to examine the association between repeated outcome measures (e.g., child weight) and a set of correlated exposure biomarkers (e.g., prenatal lead exposure). We then construct novel tests for G × E effects within the LV framework to examine effect modification of outcome-exposure association by genetic factors (e.g., the hemochromatosis gene). We consider two scenarios: one allowing dependence of the LV models on genes and the other assuming independence between the LV models and genes. We combine the two sets of estimates by shrinkage estimation to trade off bias and efficiency in a data-adaptive way. Using simulations, we evaluate the properties of the shrinkage estimates, and in particular, we demonstrate the need for this data-adaptive shrinkage given repeated outcome measures, exposure measures possibly repeated and time-varying gene-environment association. Copyright © 2014 John Wiley & Sons, Ltd.

Paths to tobacco abstinence: A repeated-measures latent class analysis.

PubMed

McCarthy, Danielle E; Ebssa, Lemma; Witkiewitz, Katie; Shiffman, Saul

2015-08-01

Knowledge of smoking change processes may be enhanced by identifying pathways to stable abstinence. We sought to identify latent classes of smokers based on their day-to-day smoking status in the first weeks of a cessation attempt. We examined treatment effects on class membership and compared classes on baseline individual differences and 6-month abstinence rates. In this secondary analysis of a double-blind randomized placebo-controlled clinical trial (N = 1,433) of 5 smoking cessation pharmacotherapies (nicotine patch, nicotine lozenge, bupropion SR, patch and lozenge, or bupropion SR and lozenge), we conducted repeated-measures latent class analysis of daily smoking status (any smoking vs. none) for the first 27 days of a quit attempt. Treatment and covariate relations with latent class membership were examined. Distal outcome analysis compared confirmed 6-month abstinence rates among the latent classes. A 5-class solution was selected. Three-quarters of smokers were in stable smoking or abstinent classes, but 25% were in classes with unstable abstinence probabilities over time. Active treatment (compared to placebo), and particularly the patch and lozenge combination, promoted early quitting. Latent classes differed in 6-month abstinence rates and on several baseline variables, including nicotine dependence, quitting history, self-efficacy, sleep disturbance, and minority status. Repeated-measures latent class analysis identified latent classes of smoking change patterns affected by treatment, related to known risk factors, and predictive of distal outcomes. Tracking behavior early in a change attempt may identify prognostic patterns of change and facilitate adaptive treatment planning. (c) 2015 APA, all rights reserved).

Disease-associated repeat instability and mismatch repair.

PubMed

Schmidt, Monika H M; Pearson, Christopher E

2016-02-01

Expanded tandem repeat sequences in DNA are associated with at least 40 human genetic neurological, neurodegenerative, and neuromuscular diseases. Repeat expansion can occur during parent-to-offspring transmission, and arise at variable rates in specific tissues throughout the life of an affected individual. Since the ongoing somatic repeat expansions can affect disease age-of-onset, severity, and progression, targeting somatic expansion holds potential as a therapeutic target. Thus, understanding the factors that regulate this mutation is crucial. DNA repair, in particular mismatch repair (MMR), is the major driving force of disease-associated repeat expansions. In contrast to its anti-mutagenic roles, mammalian MMR curiously drives the expansion mutations of disease-associated (CAG)·(CTG) repeats. Recent advances have broadened our knowledge of both the MMR proteins involved in disease repeat expansions, including: MSH2, MSH3, MSH6, MLH1, PMS2, and MLH3, as well as the types of repeats affected by MMR, now including: (CAG)·(CTG), (CGG)·(CCG), and (GAA)·(TTC) repeats. Mutagenic slipped-DNA structures have been detected in patient tissues, and the size of the slip-out and their junction conformation can determine the involvement of MMR. Furthermore, the formation of other unusual DNA and R-loop structures is proposed to play a key role in MMR-mediated instability. A complex correlation is emerging between tissues showing varying amounts of repeat instability and MMR expression levels. Notably, naturally occurring polymorphic variants of DNA repair genes can have dramatic effects upon the levels of repeat instability, which may explain the variation in disease age-of-onset, progression and severity. An increasing grasp of these factors holds prognostic and therapeutic potential. Copyright © 2015 Elsevier B.V. All rights reserved.

Musculoskeletal disorders (MSDs) and dental practice Part 2. Risk factors for dentistry, magnitude of the problem, prevention, and dental ergonomics.

PubMed

Yamalik, Nermin

2007-02-01

As a consequence of occupational stresses placed on their bodies, oral health care providers (OHP) are vulnerable to musculoskeletal disorders (MSDs). Muscular imbalance, neuromuscular inhibition, and pain and dysfunction may frequently be observed among OHP. Repeated unnatural, deviated or inadequate working postures, forceful hand movements, inadequate equipment or workplace designs and inappropriate work patterns are likely to be the particular risk factors. However, WMSDs are not an avoidable part of OHPs' professional lives. Paying the necessary attention to occupational and individual risk factors, prevalence, symptoms and consequences of WMSDs, and implementing the recommended health and safety measures can enable a long and healthy career. This review essentially aims to provide background information for OHP regarding the magnitude of the problem, particular risk factors and the available recommendations for prevention.

The influence of non-nociceptive factors on hot-plate latency in rats.

PubMed

Gunn, Amanda; Bobeck, Erin N; Weber, Ceri; Morgan, Michael M

2011-02-01

The hot plate is a widely used test to assess nociception. The effect of non-nociceptive factors (weight, sex, activity, habituation, and repeated testing) on hot-plate latency was examined. Comparison of body weight and hot-plate latency revealed a small but significant inverse correlation (light rats had longer latencies). Habituating rats to the test room for 1 hour prior to testing did not decrease hot-plate latency except for female rats tested on days 2 to 4. Hot-plate latency decreased with repeated daily testing, but this was not caused by a decrease in locomotor activity or learning to respond. Activity on the hot plate was consistent across all 4 trials, and prior exposure to a room-temperature plate caused a similar decrease in latency as rats tested repeatedly on the hot plate. Despite this decrease in baseline hot-plate latency, there was no difference in morphine antinociceptive potency. The present study shows that weight, habituation to the test room, and repeated testing can alter baseline hot-plate latency, but these effects are small and have relatively little impact on morphine antinociception. This manuscript shows that non-nociceptive factors such as body weight, habituation, and repeated testing can alter hot-plate latency, but these factors do not alter morphine potency. In sum, the hot-plate test is an easy to use and reliable method to assess supraspinally organized nociceptive responses. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

Validity of a questionnaire measuring motives for choosing foods including sustainable concerns.

PubMed

Sautron, Valérie; Péneau, Sandrine; Camilleri, Géraldine M; Muller, Laurent; Ruffieux, Bernard; Hercberg, Serge; Méjean, Caroline

2015-04-01

Since the 1990s, sustainability of diet has become an increasingly important concern for consumers. However, there is no validated multidimensional measurement of motivation in the choice of foods including a concern for sustainability currently available. In the present study, we developed a questionnaire that measures food choice motives during purchasing, and we tested its psychometric properties. The questionnaire included 104 items divided into four predefined dimensions (environmental, health and well-being, economic and miscellaneous). It was administered to 1000 randomly selected subjects participating in the Nutrinet-Santé cohort study. Among 637 responders, one-third found the questionnaire complex or too long, while one-quarter found it difficult to fill in. Its underlying structure was determined by exploratory factor analysis and then internally validated by confirmatory factor analysis. Reliability was also assessed by internal consistency of selected dimensions and test-retest repeatability. After selecting the most relevant items, first-order analysis highlighted nine main dimensions: labeled ethics and environment, local and traditional production, taste, price, environmental limitations, health, convenience, innovation and absence of contaminants. The model demonstrated excellent internal validity (adjusted goodness of fit index = 0.97; standardized root mean square residuals = 0.07) and satisfactory reliability (internal consistency = 0.96, test-retest repeatability coefficient ranged between 0.31 and 0.68 over a mean 4-week period). This study enabled precise identification of the various dimensions in food choice motives and proposed an original, internally valid tool applicable to large populations for assessing consumer food motivation during purchasing, particularly in terms of sustainability. Copyright © 2014 Elsevier Ltd. All rights reserved.

A contralateral repeated bout effect attenuates induction of NF-κB DNA binding following eccentric exercise.

PubMed

Xin, Ling; Hyldahl, Robert D; Chipkin, Stuart R; Clarkson, Priscilla M

2014-06-01

We investigated the existence of contralateral repeated bout effect and tested if the attenuation of nuclear factor-kappa B (NF-κB; an important regulator of muscle inflammation) induction following eccentric exercise is a potential mechanism. Thirty-one healthy men performed two bouts of knee extension eccentric exercise, initially with one leg and then with the opposite leg 4 wk later. Vastus lateralis muscle biopsies of both exercised and control legs were taken 3 h postexercise. Knee extension isometric and isokinetic strength (60°/sec and 180°/sec) were measured at baseline, pre-exercise, immediately postexercise, and 1/day for 5 days postexercise. Serum creatine kinase (CK) activity and muscle soreness were assessed at baseline and 1/day for 5 days postexercise. NF-κB (p65) DNA-binding activity was measured in the muscle biopsies. Isometric strength loss was lower in bout 2 than in bout 1 at 24, 72, and 96 h postexercise (P < 0.05). Isokinetic strength (60°/s and 180°/s) was reduced less in bout 2 than in bout 1 at 72 h postexercise (P < 0.01). There were no significant differences between bouts for postexercise CK activity or muscle soreness. p65 DNA-binding activity was increased following eccentric exercise (compared with the control leg) in bout 1 (122.9% ± 2.6%; P < 0.001) and bout 2 (109.1% ± 3.0%; P < 0.05). Compared with bout 1, the increase in NF-κB DNA-binding activity postexercise was attenuated after bout 2 (P = 0.0008). Repeated eccentric exercise results in a contralateral repeated bout effect, which could be due to the attenuated increase in NF-κB activity postexercise. Copyright © 2014 the American Physiological Society.

Oxygen uptake during repeated-sprint exercise.

PubMed

McGawley, Kerry; Bishop, David J

2015-03-01

Repeated-sprint ability appears to be influenced by oxidative metabolism, with reductions in fatigue and improved sprint times related to markers of aerobic fitness. The aim of the current study was to measure the oxygen uptake (VO₂) during the first and last sprints during two, 5 × 6-s repeated-sprint bouts. Cross-sectional study. Eight female soccer players performed two, consecutive, 5 × 6-s maximal sprint bouts (B1 and B2) on five separate occasions, in order to identify the minimum time (trec) required to recover total work done (Wtot) in B1. On a sixth occasion, expired air was collected during the first and last sprint of B1 and B2, which were separated by trec. The trec was 10.9 ± 1.1 min. The VO₂ during the first sprint was significantly less than the last sprint in each bout (p<0.001), and the estimated aerobic contribution to the final sprint (measured in kJ) was significantly related to VO₂max in both B1 (r=0.81, p=0.015) and B2 (r=0.93, p=0.001). In addition, the VO₂ attained in the final sprint was not significantly different from VO₂max in B1 (p=0.284) or B2 (p=0.448). The current study shows that the VO₂ increases from the first to the last of 5 × 6-s sprints and that VO₂max may be a limiting factor to performance in latter sprints. Increasing V˙O₂max in team-sport athletes may enable increased aerobic energy delivery, and consequently work done, during a bout of repeated sprints. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Helicopter noise measurements repeatability program final report

DOT National Transportation Integrated Search

1987-09-01

This report summarizes the findings of the Helicopter Noise Measurement Repeatability Program (HNMRP), which was initiated by the International Civil Aviation Organization (ICAO) Committee on Aviation Environmental Protection (CAEP) Working Group II ...

Short- and long-term variability of radon progeny concentration in dwellings in the Czech Republic.

PubMed

Slezáková, M; Navrátilová Rovenská, K; Tomásek, L; Holecek, J

2013-03-01

In this paper, repeated measurements of radon progeny concentration in dwellings in the Czech Republic are described. Two distinct data sets are available: one based on present measurements in 170 selected dwellings in the Central Bohemian Pluton with a primary measurement carried out in the 1990s and the other based on 1920 annual measurements in 960 single-family houses in the Czech Republic in 1992 and repeatedly in 1993. The analysis of variance model with random effects is applied to data to evaluate the variability of measurements. The calculated variability attributable to repeated measurements is compared with results from other countries. In epidemiological studies, ignoring the variability of measurements may lead to biased estimates of risk of lung cancer.

Factors Associated With Preterm Infants' Circadian Sleep/Wake Patterns at the Hospital.

PubMed

Lan, Hsiang-Yun; Yin, Ti; Chen, Jyu-Lin; Chang, Yue-Cune; Liaw, Jen-Jiuan

2017-08-01

This prospective repeated-measures study explored potential factors (postmenstrual age, body weight, gender, chronological age, illness severity, and circadian rhythm) related to preterm infants' circadian sleep/wake patterns. Circadian sleep/wake patterns were measured using an Actiwatch for 3 continuous days in preterm infants (gestational age of 28-36.4 weeks) in a neonatal intensive care unit and hospital nursery. Potential factors associated with circadian sleep/wake patterns were analyzed using the generalized estimating equation. For our sample of 30 preterm infants, better sleep/wake patterns were associated with male gender, younger postmenstrual and chronological age, lower body weight, and less illness severity. Preterm infants' total sleep time ( B = 41.828, p < .01) and percentage of sleep time ( B = 3.711, p < .01) were significantly longer at night than during the day. These findings can help clinicians recognize preterm infants' sleep problems, signaling the need to provide individualized support to maintain these infants' sleep quality during their early life.

The Beast of Aggregating Cognitive Load Measures in Technology-Based Learning

ERIC Educational Resources Information Center

Leppink, Jimmie; van Merriënboer, Jeroen J. G.

2015-01-01

An increasing part of cognitive load research in technology-based learning includes a component of repeated measurements, that is: participants are measured two or more times on the same performance, mental effort or other variable of interest. In many cases, researchers aggregate scores obtained from repeated measurements to one single sum or…

LPA gene: interaction between the apolipoprotein(a) size ('kringle IV' repeat) polymorphism and a pentanucleotide repeat polymorphism influences Lp(a) lipoprotein level.

PubMed

Røsby, O; Berg, K

2000-01-01

In order to search for factors influencing the Lp(a) lipoprotein level, we have examined the apolipoprotein(a) (apo(a)) size polymorphism as well as a pentanucleotide (TTTTA) repeat polymorphism in the 5' control region of the LPA gene. Lp(a) lipoprotein levels were compared between individuals with different genotypes as defined by pulsed field gel electrophoresis of DNA plugs, and PCR of DNA samples followed by polyacrylamide gel electrophoresis. DNA plugs and DNA were prepared from blood samples collected from blood donors. Twenty-seven different K IV repeat alleles were observed in the 71 women and 92 men from which apo(a) size polymorphism results were obtained. Alleles encoding 26-32 Kringle IV repeats were the most frequent. Alleles encoding seven to 11 TTTTA repeats were detected in the 84 women and 122 men included in the pentanucleotide polymorphism study, and homozygosity for eight TTTTA repeats was the most common genotype. The eight TTTTA repeat allele occurred with almost any apo(a) allele. An inverse relationship between number of K IV repeats and Lp(a) concentration was confirmed. The contributions of the apo(a) size polymorphism and the pentanucleotide repeat polymorphism to the interindividual variance of Lp(a) lipoprotein concentrations were 9.7 and 3.5%, respectively (type IV sum of squares). Nineteen per cent of the variance in Lp(a) lipoprotein level appeared to be the result of the multiplication product (interaction) between the apo(a) size polymorphism and the pentanucleotide repeat polymorphism. The contribution of the apo(a) size polymorphism alone to the variation in Lp(a) lipoprotein level was lower than previously reported. However, the multiplicative interaction effect between the K IV repeat polymorphism and the pentanucleotide repeat polymorphism may be an important factor explaining the variation in Lp(a) lipoprotein levels among the populations.

ICAO helicopter noise measurement repeatability program : U.S. test report, Bell 206L-1, noise measurement flight test

DOT National Transportation Integrated Search

1985-09-30

This document reports the findings of the U.S. test team's participation in the Helicopter Noise Measurement Repeatability Program (HNMRP) conducted under the direction of the International Civil Aviation Organization's (ICAO) Committee on Aviation E...

Reliability of perfluoroalkyl substances in plasma of 100 women in two consecutive pregnancies

PubMed Central

Papadopoulou, Eleni; Haug, Line S.; Sabaredzovic, Azemira; Eggesbø, Merete; Longnecker, Matthew P.

2015-01-01

The potential toxicity of background exposure to perfluoroalkyl substances (PFASs) is currently under active investigation. Such investigations typically rely on a single measure of PFAS concentration, yet the longer-term reliability of a single measure has not been well characterized, especially among reproductive-aged women. Our aim was to investigate the association between PFAS plasma concentrations of 100 women in two consecutive pregnancies and explore changes in plasma concentration related to reproductive factors. The women in our study were enrolled in the Norwegian Mother and Child Cohort Study (MoBa) from 2003 to 2009. About half of them breastfed exclusively for 6 months and the rest of the participants did not breastfeed between the two consecutive pregnancies (median time between pregnancies: 18 months). Maternal blood was collected at mid-pregnancy and plasma was analyzed for 10 PFASs. Statistical analyses were restricted to 6 PFASs that were quantifiable in more than 80% of the samples. We estimated the correlation between repeated PFAS measurements, the percentage change between pregnancies and the effect of several reproductive factors in multivariate linear regression models of PFAS concentration in the second pregnancy. The Pearson correlation coefficient between repeated PFAS measurements was, for perfluorooctane sulfonate (PFOS), 0.80; perfluorooctanoate (PFOA), 0.50; perfluorohexane sulfonate (PFHxS), 0.74; perfluorononanoate (PFNA), 0.39; perfluoroundecanoate (PFUnDA), 0.71; and perfluorodecanoate (PFDA), 0.60. Adjustment for maternal age, delivery year, and time and breastfeeding between pregnancies did not substantially affect the observed correlations. We found 44-47% median reductions in the concentrations of PFOS, PFOA and PFHxS between pregnancies, while the change in concentrations between pregnancies was smaller and more variable for PFNA, PFUnDA and PFDA. The variation in plasma concentrations in the second pregnancy was mainly accounted for by the concentration in the first pregnancy; for PFOS, PFOA, and PFNA, breastfeeding also accounted for a substantial proportion. In conclusion, we found the reliability of PFAS measurements in maternal plasma to be moderate to high, and in these data, several factors, especially breastfeeding, were related to plasma concentrations. PMID:25957838

Reliability of perfluoroalkyl substances in plasma of 100 women in two consecutive pregnancies.

PubMed

Papadopoulou, Eleni; Haug, Line S; Sabaredzovic, Azemira; Eggesbø, Merete; Longnecker, Matthew P

2015-07-01

The potential toxicity of background exposure to perfluoroalkyl substances (PFASs) is currently under active investigation. Such investigations typically rely on a single measure of PFAS concentration, yet the longer-term reliability of a single measure has not been well characterized, especially among reproductive-aged women. Our aim was to investigate the association between PFAS plasma concentrations of 100 women in two consecutive pregnancies and explore changes in plasma concentration related to reproductive factors. The women in our study were enrolled in the Norwegian Mother and Child Cohort Study (MoBa) from 2003 to 2009. About half of them breastfed exclusively for 6 months and the rest of the participants did not breastfeed between the two consecutive pregnancies (median time between pregnancies: 18 months). Maternal blood was collected at mid-pregnancy and plasma was analyzed for 10 PFASs. Statistical analyses were restricted to 6 PFASs that were quantifiable in more than 80% of the samples. We estimated the correlation between repeated PFAS measurements, the percentage change between pregnancies and the effect of several reproductive factors in multivariate linear regression models of PFAS concentrations in the second pregnancy. The Pearson correlation coefficient between repeated PFAS measurements was, for perfluorooctane sulfonate (PFOS), 0.80; perfluorooctanoate (PFOA), 0.50; perfluorohexane sulfonate (PFHxS), 0.74; perfluorononanoate (PFNA), 0.39; perfluoroundecanoate (PFUnDA), 0.71; and perfluorodecanoate (PFDA), 0.60. Adjustment for maternal age, delivery year, and time and breastfeeding between pregnancies did not substantially affect the observed correlations. We found 44-47% median reductions in the concentrations of PFOS, PFOA and PFHxS between pregnancies, while the change in concentrations between pregnancies was smaller and more variable for PFNA, PFUnDA and PFDA. The variation in plasma concentrations in the second pregnancy was mainly accounted for by the concentration in the first pregnancy; for PFOS, PFOA, and PFNA, breastfeeding also accounted for a substantial proportion. In conclusion, we found the reliability of PFAS measurements in maternal plasma to be moderate to high, and in these data, several factors, especially breastfeeding, were related to plasma concentrations. Copyright © 2015 Elsevier Inc. All rights reserved.

Repeat Radiosurgery for Trigeminal Neuralgia.

PubMed

Helis, Corbin A; Lucas, John T; Bourland, J Daniel; Chan, Michael D; Tatter, Stephen B; Laxton, Adrian W

2015-11-01

Repeat Gamma Knife radiosurgery (GKRS) is an established option for patients whose pain has recurred after the initial procedure, with reported success rates varying from 68% to 95%. Predictive factors for response to the repeat GKRS are ill-defined. This cohort study aimed to report the outcomes and factors predictive of success for patients who have undergone repeated GKRS for trigeminal neuralgia at Wake Forest University Baptist Medical Center. Between 1999 and 2013, 152 patients underwent repeat GKRS at Wake Forest, 125 of whom were available for long-term follow-up. A retrospective chart review and telephone interviews were conducted to determine background medical history, dosimetric data, outcomes, and adverse effects of the procedure. Eighty-four percent of patients achieved at least Barrow Neurological Institute (BNI) IIIb pain relief, with 46% achieving BNI I. The 1-, 3-, and 5-year rates of BNI I pain relief were 63%, 50%, and 37%, respectively. The 1-, 3-, and 5-year rates of BNI IIIb or better pain relief were 74%, 59%, and 46%, respectively. One patient experienced bothersome numbness and 2 patients developed anesthesia dolorosa. The dominant predictive factors for pain relief were facial numbness after the first GKRS and a positive pain response to the first GKRS. Repeat GKRS is an effective method of treating recurrent trigeminal neuralgia. Patients who have facial numbness after the first treatment and a positive pain response to the first GKRS are significantly more likely to respond well to the second treatment.

Time to stability differences between male and female dancers after landing from a jump on flat and inclined floors.

PubMed

Pappas, Evangelos; Kremenic, Ian; Liederbach, Marijeanne; Orishimo, Karl F; Hagins, Marshall

2011-07-01

To determine the effect of gender and inclined floor on time to stability (TTS) after landing from a vertical jump. This study used a repeated measures design with male and female professional dancers landing on a flat and 4 inclined floors. A repeated measures univariate analysis of variance (gender × floor) was performed on TTS in the anterior-posterior and medial-lateral directions. Biomechanics laboratory. Twenty-three female and 13 male professional dancers. Gender and floor inclination (flat, posterior, anterior, lateral, and medial). Time to stability in the anterior-posterior and medial-lateral directions after landing from a vertical jump. Female dancers exhibited longer TTS in both directions (P ≤ 0.05). Floor inclination or the interaction of gender × floor did not have an effect on TTS (P > 0.3). Female dancers exhibited longer TTS after landing from a vertical jump compared with their male counterparts. This balance difference may be a factor related to the higher rate of ankle sprain among female dancers. Additionally, professional dancers exhibited similar TTS when landing on flat and inclined floors.

Improved Knowledge Retention Among Clinical Pharmacy Students Using an Anthropology Classroom Assessment Technique

PubMed Central

Parton, Jason M.

2014-01-01

Objective. To adapt a classroom assessment technique (CAT) from an anthropology course to a diabetes module in a clinical pharmacy skills laboratory and to determine student knowledge retention from baseline. Design. Diabetes item stems, focused on module objectives, replaced anthropology terms. Answer choices, coded to Bloom’s Taxonomy, were expanded to include higher-order thinking. Students completed the online 5-item probe 4 times: prelaboratory lecture, postlaboratory, and at 6 months and 12 months after laboratory. Statistical analyses utilized a single factor, repeated measures design using rank transformations of means with a Mann-Whitney-Wilcoxon test. Assessment. The CAT revealed a significant increase in knowledge from prelaboratory compared to all postlaboratory measurements (p<0.0001). Significant knowledge retention was maintained with basic terms, but declined with complex terms between 6 and 12 months. Conclusion. The anthropology assessment tool was effectively adapted using Bloom’s Taxonomy as a guide and, when used repeatedly, demonstrated knowledge retention. Minimal time was devoted to application of the probe making it an easily adaptable CAT. PMID:25258445

Quantifying introgression risk with realistic population genetics.

PubMed

Ghosh, Atiyo; Meirmans, Patrick G; Haccou, Patsy

2012-12-07

Introgression is the permanent incorporation of genes from the genome of one population into another. This can have severe consequences, such as extinction of endemic species, or the spread of transgenes. Quantification of the risk of introgression is an important component of genetically modified crop regulation. Most theoretical introgression studies aimed at such quantification disregard one or more of the most important factors concerning introgression: realistic genetical mechanisms, repeated invasions and stochasticity. In addition, the use of linkage as a risk mitigation strategy has not been studied properly yet with genetic introgression models. Current genetic introgression studies fail to take repeated invasions and demographic stochasticity into account properly, and use incorrect measures of introgression risk that can be manipulated by arbitrary choices. In this study, we present proper methods for risk quantification that overcome these difficulties. We generalize a probabilistic risk measure, the so-called hazard rate of introgression, for application to introgression models with complex genetics and small natural population sizes. We illustrate the method by studying the effects of linkage and recombination on transgene introgression risk at different population sizes.

Quantifying introgression risk with realistic population genetics

PubMed Central

Ghosh, Atiyo; Meirmans, Patrick G.; Haccou, Patsy

2012-01-01

Introgression is the permanent incorporation of genes from the genome of one population into another. This can have severe consequences, such as extinction of endemic species, or the spread of transgenes. Quantification of the risk of introgression is an important component of genetically modified crop regulation. Most theoretical introgression studies aimed at such quantification disregard one or more of the most important factors concerning introgression: realistic genetical mechanisms, repeated invasions and stochasticity. In addition, the use of linkage as a risk mitigation strategy has not been studied properly yet with genetic introgression models. Current genetic introgression studies fail to take repeated invasions and demographic stochasticity into account properly, and use incorrect measures of introgression risk that can be manipulated by arbitrary choices. In this study, we present proper methods for risk quantification that overcome these difficulties. We generalize a probabilistic risk measure, the so-called hazard rate of introgression, for application to introgression models with complex genetics and small natural population sizes. We illustrate the method by studying the effects of linkage and recombination on transgene introgression risk at different population sizes. PMID:23055068

Testing Mean Differences among Groups: Multivariate and Repeated Measures Analysis with Minimal Assumptions

PubMed Central

Bathke, Arne C.; Friedrich, Sarah; Pauly, Markus; Konietschke, Frank; Staffen, Wolfgang; Strobl, Nicolas; Höller, Yvonne

2018-01-01

ABSTRACT To date, there is a lack of satisfactory inferential techniques for the analysis of multivariate data in factorial designs, when only minimal assumptions on the data can be made. Presently available methods are limited to very particular study designs or assume either multivariate normality or equal covariance matrices across groups, or they do not allow for an assessment of the interaction effects across within-subjects and between-subjects variables. We propose and methodologically validate a parametric bootstrap approach that does not suffer from any of the above limitations, and thus provides a rather general and comprehensive methodological route to inference for multivariate and repeated measures data. As an example application, we consider data from two different Alzheimer’s disease (AD) examination modalities that may be used for precise and early diagnosis, namely, single-photon emission computed tomography (SPECT) and electroencephalogram (EEG). These data violate the assumptions of classical multivariate methods, and indeed classical methods would not have yielded the same conclusions with regards to some of the factors involved. PMID:29565679

Barriers to repeated assessment of verbal learning and memory: a comparison of international shopping list task and rey auditory verbal learning test on build-up of proactive interference.

PubMed

Rahimi-Golkhandan, S; Maruff, P; Darby, D; Wilson, P

2012-11-01

Proactive interference (PI) that remains unidentified can confound the assessment of verbal learning, particularly when its effects vary from one population to another. The International Shopping List Task (ISLT) is a new measure that provides multiple forms that can be equated for linguistic factors across cultural groups. The aim of this study was to examine the build-up of PI on two measures of verbal learning-a traditional test of list learning (Rey Auditory Verbal Learning Test, RAVLT) and the ISLT. The sample consisted of 61 healthy adults aged 18-40. Each test had three parallel forms, each recalled three times. Results showed that repeated administration of the ISLT did not result in significant PI effects, unlike the RAVLT. Although these PI effects, observed during short retest intervals, may not be as robust under normal clinical administrations of the tests, the results suggest that the choice of the verbal learning test should be guided by the knowledge of PI effects and the susceptibility of particular patient groups to this effect.

The influence of stimulants, sedatives, and fatigue on tunnel vision: risk factors for driving and piloting.

PubMed

Mills, K C; Spruill, S E; Kanne, R W; Parkman, K M; Zhang, Y

2001-01-01

A computerized task was used in two studies to examine the influence of stimulants, sedatives, and fatigue on single-target and divided-attention responses in different parts of the visual field. The drug effects were evaluated over time with repeated behavioral and subjective measures against ascending and descending drug levels. In the first study, 18 fully rested participants received placebo, alprazolam (0.5 mg), and dextroamphetamine (10 mg). Alprazolam impairs performance, whereas dextroamphetamine induces enhancement and tunnel vision. Study 2 exposed 32 participants to fatigue and no fatigue with a repeated-measures crossover design. Four independent groups subsequently received placebo, dextroamphetamine (10 mg), caffeine (250 mg), or alcohol (.07%). Under fatigue, stimulants have no performance-enhancing effects, whereas impairment from alcohol is severe. Under no fatigue, alcohol has a modest effect, caffeine has no effect, and dextroamphetamine significantly enhances divided-attention performance coincident with tunnel vision. Participants rate all drug effects more stimulating and less sedating while fatigued. Implications for transportation safety are discussed. Actual or potential applications of this research include driver and pilot training.

A multiresolution approach for the convergence acceleration of multivariate curve resolution methods.

PubMed

Sawall, Mathias; Kubis, Christoph; Börner, Armin; Selent, Detlef; Neymeyr, Klaus

2015-09-03

Modern computerized spectroscopic instrumentation can result in high volumes of spectroscopic data. Such accurate measurements rise special computational challenges for multivariate curve resolution techniques since pure component factorizations are often solved via constrained minimization problems. The computational costs for these calculations rapidly grow with an increased time or frequency resolution of the spectral measurements. The key idea of this paper is to define for the given high-dimensional spectroscopic data a sequence of coarsened subproblems with reduced resolutions. The multiresolution algorithm first computes a pure component factorization for the coarsest problem with the lowest resolution. Then the factorization results are used as initial values for the next problem with a higher resolution. Good initial values result in a fast solution on the next refined level. This procedure is repeated and finally a factorization is determined for the highest level of resolution. The described multiresolution approach allows a considerable convergence acceleration. The computational procedure is analyzed and is tested for experimental spectroscopic data from the rhodium-catalyzed hydroformylation together with various soft and hard models. Copyright © 2015 Elsevier B.V. All rights reserved.

Influence of the visual environment on the postural stability in healthy older women.

PubMed

Brooke-Wavell, K; Perrett, L K; Howarth, P A; Haslam, R A

2002-01-01

A poor postural stability in older people is associated with an increased risk of falling. It is recognized that visual environment factors (such as poor lighting and repeating patterns on escalators) may contribute to falls, but little is known about the effects of the visual environment on postural stability in the elderly. To determine whether the postural stability of older women (using body sway as a measure) differed under five different visual environment conditions. Subjects were 33 healthy women aged 65-76 years. Body sway was measured using an electronic force platform which identified the location of their centre of gravity every 0.05 s. Maximal lateral sway and anteroposterior sway were determined and the sway velocity calculated over 1-min trial periods. Body sway was measured under each of the following conditions: (1) normal laboratory lighting (186 lx); (2) moderate lighting (10 lx); (3) dim lighting (1 lx); (4) eyes closed, and (5) repeating pattern projected onto a wall. Each measure of the postural stability was significantly poorer in condition 4 (eyes closed) than in all other conditions. Anteroposterior sway was greater in condition 3 than in conditions 1 and 2, whilst the sway velocity was greater in condition 3 than in condition 2. Lateral sway did not differ significantly between different lighting levels (conditions 1-3). A projected repeating pattern (condition 5) did not significantly influence the postural stability relative to condition 1. The substantially greater body sway with eyes closed than with eyes open confirms the importance of vision in maintaining the postural stability. At the lowest light level, the body sway was significantly increased as compared with the other light levels, but was still substantially smaller than on closing the eyes. A projected repeating pattern did not influence the postural stability. Dim lighting levels and removing visual input appear to be associated with a poorer postural stability in older people and hence might be associated with an increased risk of falls. Copyright 2002 S. Karger AG, Basel

Comparison of stethoscope bell and diaphragm, and of stethoscope tube length, for clinical blood pressure measurement.

PubMed

Liu, Chengyu; Griffiths, Clive; Murray, Alan; Zheng, Dingchang

2016-06-01

This study investigated the effect of stethoscope side and tube length on auscultatory blood pressure (BP) measurement. Thirty-two healthy participants were studied. For each participant, four measurements with different combinations of stethoscope characteristics (bell or diaphragm side, standard or short tube length) were each recorded at two repeat sessions, and eight Korotkoff sound recordings were played twice on separate days to one experienced listener to determine the systolic and diastolic BPs (SBP and DBP). Analysis of variance was carried out to study the measurement repeatability between the two repeat sessions and between the two BP determinations on separate days, as well as the effects of stethoscope side and tube length. There was no significant paired difference between the repeat sessions and between the repeat determinations for both SBP and DBP (all P-values>0.10, except the repeat session for SBP using short tube and diaphragm). The key result was that there was a small but significantly higher DBP on using the bell in comparison with the diaphragm (0.66 mmHg, P=0.007), and a significantly higher SBP on using the short tube in comparison with the standard length (0.77 mmHg, P=0.008). This study shows that stethoscope characteristics have only a small, although statistically significant, influence on clinical BP measurement. Although this helps understand the measurement technique and resolves questions in the published literature, the influence is not clinically significant.

Comparison of stethoscope bell and diaphragm, and of stethoscope tube length, for clinical blood pressure measurement

PubMed Central

Griffiths, Clive; Murray, Alan; Zheng, Dingchang

2016-01-01

Objective This study investigated the effect of stethoscope side and tube length on auscultatory blood pressure (BP) measurement. Methods Thirty-two healthy participants were studied. For each participant, four measurements with different combinations of stethoscope characteristics (bell or diaphragm side, standard or short tube length) were each recorded at two repeat sessions, and eight Korotkoff sound recordings were played twice on separate days to one experienced listener to determine the systolic and diastolic BPs (SBP and DBP). Analysis of variance was carried out to study the measurement repeatability between the two repeat sessions and between the two BP determinations on separate days, as well as the effects of stethoscope side and tube length. Results There was no significant paired difference between the repeat sessions and between the repeat determinations for both SBP and DBP (all P-values>0.10, except the repeat session for SBP using short tube and diaphragm). The key result was that there was a small but significantly higher DBP on using the bell in comparison with the diaphragm (0.66 mmHg, P=0.007), and a significantly higher SBP on using the short tube in comparison with the standard length (0.77 mmHg, P=0.008). Conclusion This study shows that stethoscope characteristics have only a small, although statistically significant, influence on clinical BP measurement. Although this helps understand the measurement technique and resolves questions in the published literature, the influence is not clinically significant. PMID:26741415

Long-term effects of psychosocial factors of home and work on biomarkers of stress.

PubMed

Eller, Nanna Hurwitz; Kristiansen, Jesper; Hansen, Ase Marie

2011-02-01

The current study analyzed the relationship between psychosocial factors measured at baseline and heart rate variability (HRV) and salivary cortisol measured at baseline and again, six years later. In 2002 and 2008, measurements of HRV and salivary cortisol at three time points were obtained from 70 healthy participants (48 women and 22 men). The associations between the psychosocial factors measured in 2002 and the dependent variables, HRV and salivary cortisol measured in 2002 and 2008, were examined using a series of repeated measures ANCOVAs. The dependent variables were as follows: the logarithmically transformed levels of total power (LnTP), high frequency power (LnHF), the ratio between low and high frequency power (LnLF/HF) and salivary cortisol (LnCortisol). For women, high social status was associated with high LnTP, high LnHF, and low LnLF/HF. In work, lack of control was associated with low LnTP, and lack of support was associated with an increased LnLF/HF ratio. For men, high social status was associated with low LnTP, low LnHF and high LnCortisol. Greater number of hours spent doing housework was associated with both low LnLF/HF and low LnCortisol, whereas a large imbalance between effort and reward was associated with low LnTP and high LnCortisol. Despite the small sample size, this study demonstrated that psychosocial factors impact levels of activity in the allostatic systems. Copyright © 2010 Elsevier B.V. All rights reserved.

Helium Mass Spectrometer Leak Detection: A Method to Quantify Total Measurement Uncertainty

NASA Technical Reports Server (NTRS)

Mather, Janice L.; Taylor, Shawn C.

2015-01-01

In applications where leak rates of components or systems are evaluated against a leak rate requirement, the uncertainty of the measured leak rate must be included in the reported result. However, in the helium mass spectrometer leak detection method, the sensitivity, or resolution, of the instrument is often the only component of the total measurement uncertainty noted when reporting results. To address this shortfall, a measurement uncertainty analysis method was developed that includes the leak detector unit's resolution, repeatability, hysteresis, and drift, along with the uncertainty associated with the calibration standard. In a step-wise process, the method identifies the bias and precision components of the calibration standard, the measurement correction factor (K-factor), and the leak detector unit. Together these individual contributions to error are combined and the total measurement uncertainty is determined using the root-sum-square method. It was found that the precision component contributes more to the total uncertainty than the bias component, but the bias component is not insignificant. For helium mass spectrometer leak rate tests where unit sensitivity alone is not enough, a thorough evaluation of the measurement uncertainty such as the one presented herein should be performed and reported along with the leak rate value.

Proceedings of the Symposium on Psychology in the Department of Defense (8th) Held in Colorado Springs, Colorado on 21-23 April 1982

DTIC Science & Technology

1982-12-01

readily visible but still represent low level flight. 33 Experimental Design and Pc,cedures. The experimental design used in this study was a 3 X 2...October 1979. Winer, B.J. Statistical principles in experimental design . New York: McGraw-Hill, 1971. 47 NONTRADITIONAL ADMISSIONS FACTORS: THE SPECIAL...Quasi- Experimental Designs for Research. Chicago: Rand McNally, 1963. R.C. Carter and H. Sbisa. Human Performance tests for repeated measurements

Evaluation of time domain and spectral domain optical coherence tomography in the measurement of diabetic macular edema.

PubMed

Forooghian, Farzin; Cukras, Catherine; Meyerle, Catherine B; Chew, Emily Y; Wong, Wai T

2008-10-01

To evaluate macular thickness and volume measurements and their intrasession repeatability in two optical coherence tomography (OCT) systems: the Stratus OCT, a time domain system, and the Cirrus HD-OCT, a spectral domain system (both by Carl Zeiss Meditec, Inc., Dublin, CA), in the context of diabetic macular edema (DME). Thirty-three eyes of 33 diabetic patients with clinically significant macular edema (CSME) were scanned in a single session by a single operator on both OCT systems. Macular thickness measurements of nine standard macular subfields and total macular volume were obtained and analyzed. Bland-Altman plots were constructed to assess agreement in macular measurements. Intraclass correlation coefficients (ICCs), coefficients of repeatability (CR(W)), and coefficients of variation (CV(W)) were used to assess intrasession repeatability. Macular thickness in nine retinal subfields and macular volume were significantly higher in the Cirrus HD-OCT system compared with the Stratus OCT system. Subfield thickness and total volume measurements, respectively, were 30 to 55 microm and 3.2 mm(3) greater for the Cirrus HD-OCT system compared with the Stratus OCT system. Both Stratus OCT and Cirrus HD-OCT systems demonstrated high intrasession repeatability, with overlapping ranges for CR(W), CV(W), and ICC. Repeatability measures (CR(W) and CV(W)) differed significantly between systems in only one of nine subfields (outer temporal subfield). Absolute measures of macular thickness and volume in patients with DME differed significantly in magnitude between the Stratus OCT and Cirrus HD-OCT systems. However, both OCT systems demonstrated high intrasessional repeatability. Although the two systems may not be used interchangeably, they appear equally reliable in generating macular measurements for clinical practice and research.

Maintaining confidentiality in prospective studies: anonymous repeated measurements via email (ARME) procedure.

PubMed

Carli, Vladimir; Hadlaczky, Gergö; Wasserman, Camilla; Stingelin-Giles, Nicola; Reiter-Theil, Stella; Wasserman, Danuta

2012-02-01

Respecting and protecting the confidentiality of data and the privacy of individuals regarding the information that they have given as participants in a research project is a cornerstone of complying with accepted research standards. However, in longitudinal studies, establishing and maintaining privacy is often challenging because of the necessity of repeated contact with participants. A novel internet-based solution is introduced here, which maintains privacy while at the same time ensures linkage of data to individual participants in a repeated measures design. With the use of the anonymous repeated measurements via email (ARME) procedure, two separate one-way communication systems are established through ad hoc email accounts and a secure study website. Strengths and limitations of the approach are discussed.

Variability in objective and subjective measures affects baseline values in studies of patients with COPD

PubMed Central

Ha, Jae Wook; Couper, David J.; O’Neal, Wanda K.; Barr, R. Graham; Bleecker, Eugene R.; Carretta, Elizabeth E.; Cooper, Christopher B.; Doerschuk, Claire M.; Drummond, M Bradley; Han, MeiLan K.; Hansel, Nadia N.; Kim, Victor; Kleerup, Eric C.; Martinez, Fernando J.; Rennard, Stephen I.; Tashkin, Donald; Woodruff, Prescott G.; Paine, Robert; Curtis, Jeffrey L.; Kanner, Richard E.

2017-01-01

Rationale Understanding the reliability and repeatability of clinical measurements used in the diagnosis, treatment and monitoring of disease progression is of critical importance across all disciplines of clinical practice and in clinical trials to assess therapeutic efficacy and safety. Objectives Our goal is to understand normal variability for assessing true changes in health status and to more accurately utilize this data to differentiate disease characteristics and outcomes. Methods Our study is the first study designed entirely to establish the repeatability of a large number of instruments utilized for the clinical assessment of COPD in the same subjects over the same period. We utilized SPIROMICS participants (n = 98) that returned to their clinical center within 6 weeks of their baseline visit to repeat complete baseline assessments. Demographics, spirometry, questionnaires, complete blood cell counts (CBC), medical history, and emphysema status by computerized tomography (CT) imaging were obtained. Results Pulmonary function tests (PFTs) were highly repeatable (ICC’s >0.9) but the 6 minute walk (6MW) was less so (ICC = 0.79). Among questionnaires, the Saint George’s Respiratory Questionnaire (SGRQ) was most repeatable. Self-reported clinical features, such as exacerbation history, and features of chronic bronchitis, often produced kappa values <0.6. Reported age at starting smoking and average number of cigarettes smoked were modestly repeatable (kappa = 0.76 and 0.79). Complete blood counts (CBC) variables produced intraclass correlation coefficients (ICC) values between 0.6 and 0.8. Conclusions PFTs were highly repeatable, while subjective measures and subject recall were more variable. Analyses using features with poor repeatability could lead to misclassification and outcome errors. Hence, care should be taken when interpreting change in clinical features based on measures with low repeatability. Efforts to improve repeatability of key clinical features such as exacerbation history and chronic bronchitis are warranted. PMID:28934249

Effect of Different Levels of Localized Muscle Fatigue on Knee Position Sense

PubMed Central

Gear, William S.

2011-01-01

There is little information available regarding how proprioceptive abilities decline as the amount of exertion increases during exercise. The purpose of this study was to determine the role of different levels of fatigue on knee joint position sense. A repeated measures design was used to examine changes in active joint reposition sense (AJRS) prior to and following three levels of fatigue. Eighteen participants performed knee extension and flexion isokinetic exercise until torque output was 90%, 70%, or 50% of the peak hamstring torque for three consecutive repetitions. Active joint reposition sense at 15, 30, or 45 degrees was tested following the isokinetic exercise session. Following testing of the first independent measure, participants were given a 20 minute rest period. Testing procedures were repeated for two more exercise sessions following the other levels of fatigue. Testing of each AJRS test angle was conducted on three separate days with 48 hours between test days. Significant main effect for fatigue was indicated (p = 0.001). Pairwise comparisons indicated a significant difference between the pre-test and following 90% of peak hamstring torque (p = 0.02) and between the pre-test and following 50% of peak hamstring torque (p = 0.02). Fatigue has long been theorized to be a contributing factor in decreased proprioceptive acuity, and therefore a contributing factor to joint injury. The findings of the present study indicate that fatigue may have an effect on proprioception following mild and maximum fatigue. Key points A repeated measures design was used to examine the effect of different levels of fatigue on active joint reposition sense (AJRS) of the knee at joint angles of 15°, 30° and 45° of flexion. A statistically significant main effect for fatigue was found, specifically between no fatigue and mild fatigue and no fatigue and maximum fatigue. A statistically significant interaction effect between AJRS and fatigue was not found. Secondary analysis of the results indicated a potential plateau effect of AJRS as fatigue continues to increase. Further investigation of the effect of increasing levels of fatigue on proprioception is warranted. PMID:24149565

Effect of different levels of localized muscle fatigue on knee position sense.

PubMed

Gear, William S

2011-01-01

There is little information available regarding how proprioceptive abilities decline as the amount of exertion increases during exercise. The purpose of this study was to determine the role of different levels of fatigue on knee joint position sense. A repeated measures design was used to examine changes in active joint reposition sense (AJRS) prior to and following three levels of fatigue. Eighteen participants performed knee extension and flexion isokinetic exercise until torque output was 90%, 70%, or 50% of the peak hamstring torque for three consecutive repetitions. Active joint reposition sense at 15, 30, or 45 degrees was tested following the isokinetic exercise session. Following testing of the first independent measure, participants were given a 20 minute rest period. Testing procedures were repeated for two more exercise sessions following the other levels of fatigue. Testing of each AJRS test angle was conducted on three separate days with 48 hours between test days. Significant main effect for fatigue was indicated (p = 0.001). Pairwise comparisons indicated a significant difference between the pre-test and following 90% of peak hamstring torque (p = 0.02) and between the pre-test and following 50% of peak hamstring torque (p = 0.02). Fatigue has long been theorized to be a contributing factor in decreased proprioceptive acuity, and therefore a contributing factor to joint injury. The findings of the present study indicate that fatigue may have an effect on proprioception following mild and maximum fatigue. Key pointsA repeated measures design was used to examine the effect of different levels of fatigue on active joint reposition sense (AJRS) of the knee at joint angles of 15°, 30° and 45° of flexion.A statistically significant main effect for fatigue was found, specifically between no fatigue and mild fatigue and no fatigue and maximum fatigue.A statistically significant interaction effect between AJRS and fatigue was not found.Secondary analysis of the results indicated a potential plateau effect of AJRS as fatigue continues to increase.Further investigation of the effect of increasing levels of fatigue on proprioception is warranted.

What Is the Risk of Anastomotic Leak After Repeat Intestinal Resection in Patients With Crohn's Disease?

PubMed

Johnston, W Forrest; Stafford, Caitlin; Francone, Todd D; Read, Thomas E; Marcello, Peter W; Roberts, Patricia L; Ricciardi, Rocco

2017-12-01

Approximately half of Crohn's patients require intestinal resection, and many need repeat resections. The purpose of this study was to evaluate the increased risk of clinical anastomotic leak in patients with a history of previous intestinal resection undergoing repeat resection with anastomosis for Crohn's disease. This was a retrospective analysis of prospectively collected departmental data with 100% capture. The study was conducted at the department of colorectal surgery in a tertiary care teaching hospital between July 2007 and March 2016. A cohort of consecutive patients with Crohn's disease who were treated with intestinal resection and anastomosis, excluding patients with proximal fecal diversion, were included. The cohort was divided into 2 groups, those with no previous resection compared with those with previous resection. Clinical anastomotic leak within 30 days of surgery was measured. Of the 206 patients who met criteria, 83 patients had previous intestinal resection (40%). The 2 groups were similar in terms of patient factors, immune-suppressing medication use, and procedural factors. Overall, 20 clinical anastomotic leaks were identified (10% leak rate). There were 6 leaks (5%) detected in patients with no previous intestinal resection and 14 leaks (17%) detected in patients with a history of previous intestinal resection (p < 0.005). The OR of anastomotic leak in patients with Crohn's disease with previous resection compared with no previous resection was 3.5 (95% CI, 1.3-9.4). Patients with 1 previous resection (n = 53) had a leak rate of 13%, whereas patients with ≥2 previous resections (n = 30) had a leak rate of 23%. The number of previous resections correlated with increasing risk for clinical anastomotic leak (correlation coefficient = 0.998). This was a retrospective study with limited data to perform a multivariate analysis. Repeat intestinal resection in patients with Crohn's disease is associated with an increased rate of anastomotic leakage when compared with initial resection despite similar patient, medication, and procedural factors. See Video Abstract at http://links.lww.com/DCR/A459.

Repeatability of intravital capillaroscopic measurement of capillary density.

PubMed

Lamah, M; Chaudhry, H; Mortimer, P S; Dormandy, J A

1996-01-01

The reliability of intravital capillaroscopy for determining capillary density (CD) of skin has been questioned because it depends upon the variability of the measuring process and subjective interpretation of data as well as the intrinsic heterogeneity of capillary spacing. The aim of this study was to assess the repeatability of a standardised method for measuring CD of the skin of the dorsum of foot. In each of 30 subjects (10 controls and 20 patients with peripheral vascular disease), the foot was systematically mapped by examining 20 sites on the dorsum of foot and 2 sites on each toe, using white light (native) videomicroscopy at 40 x magnification. Off-line analysis of videoprints was then undertaken to determine CD at each site, by counting capillaries within areas of acceptable photographic quality only, having first defined the criteria for counting capillaries. The mean values were then calculated and taken to represent the CD of the foot or toes. Repeatability of the measuring equipment was first assessed by noting the presence or absence of each corresponding capillary in 2 prints, taken at intervals of hours or days (in 10 subjects) or months (in 2 patients), of an identical area of skin which was marked by a microtattoo on the first occasion. On average, 95% of corresponding capillaries were identified in both prints (from controls and patients), thus implying little intrinsic temporal variation of capillary anatomy as well as excellent repeatability of the measuring equipment. Repeatability of data analysis was assessed by the same observer reading the same 20 prints in a blinded manner on three separate occasions (intraobserver repeatability), and 2 observers reading the same 24 prints (interobserver repeatability). The mean coefficient of intraobserver variation of CD estimate was 5.6% and the interobserver correlation coefficient was 0.94. Finally, overall repeatability of the method was assessed by repeating the procedure on a subsequent occasion (mean time interval of 5 days) in 10 subjects. The rate of agreement in mean CD between the two procedures [defined as 100- (difference between the two measurements/mean of the two measurements) x 100]% ranged from 86.4 to 97.1% (mean 93.5%). Thus using the above methodological technique, native capillaroscopy can be reliably used to determine CD of the dorsum of foot in comparing patient subgroups, as well as in longitudinal studies.

Validation of a 3D CT method for measurement of linear wear of acetabular cups

PubMed Central

2011-01-01

Background We evaluated the accuracy and repeatability of a 3D method for polyethylene acetabular cup wear measurements using computed tomography (CT). We propose that the method be used for clinical in vivo assessment of wear in acetabular cups. Material and methods Ultra-high molecular weight polyethylene cups with a titanium mesh molded on the outside were subjected to wear using a hip simulator. Before and after wear, they were (1) imaged with a CT scanner using a phantom model device, (2) measured using a coordinate measurement machine (CMM), and (3) weighed. CMM was used as the reference method for measurement of femoral head penetration into the cup and for comparison with CT, and gravimetric measurements were used as a reference for both CT and CMM. Femoral head penetration and wear vector angle were studied. The head diameters were also measured with both CMM and CT. The repeatability of the method proposed was evaluated with two repeated measurements using different positions of the phantom in the CT scanner. Results The accuracy of the 3D CT method for evaluation of linear wear was 0.51 mm and the repeatability was 0.39 mm. Repeatability for wear vector angle was 17°. Interpretation This study of metal-meshed hip-simulated acetabular cups shows that CT has the capacity for reliable measurement of linear wear of acetabular cups at a clinically relevant level of accuracy. PMID:21281259

Effect Sizes and their Intervals: The Two-Level Repeated Measures Case

ERIC Educational Resources Information Center

Algina, James; Keselman, H. J.; Penfield, Randall D.

2005-01-01

Probability coverage for eight different confidence intervals (CIs) of measures of effect size (ES) in a two-level repeated measures design was investigated. The CIs and measures of ES differed with regard to whether they used least squares or robust estimates of central tendency and variability, whether the end critical points of the interval…

An investigation of thermal changes of various permanent dental cements.

PubMed

Duymus, Zeynep Yesil; Yilmaz, Baykal; Karaalioglu, F Osman

2009-05-01

The aim of this study was to investigate and compare the temperature rises which occurred during the setting reactions of different permanent cements used to lute fixed partial prosthodontics. In this study, four cements were used. They were mixed in three different proportions: according to manufacturers' recommendations, at doubled powder ratio, and at doubled liquid ratio. With a thermocouple, the temperature rises which occurred during the setting reactions were measured. For each proportion, the measurement was repeated five times such that a total of 60 measurements were done for the four different cements. Data were analyzed using analysis of variance (ANOVA). ANOVA results showed that cement type and the interaction between cement type and the powder-liquid ratio were statistically significant factors (p<0.001). Similarly, the powder-liquid ratio was a statistically significant (p<0.01) factor. Among the dental cements tested, zinc phosphate cement showed the highest temperature rise during setting reaction, whereas glass ionomer cement showed the lowest.

The multiple roles of epidermal growth factor repeat O-glycans in animal development

PubMed Central

Haltom, Amanda R; Jafar-Nejad, Hamed

2015-01-01

The epidermal growth factor (EGF)-like repeat is a common, evolutionarily conserved motif found in secreted proteins and the extracellular domain of transmembrane proteins. EGF repeats harbor six cysteine residues which form three disulfide bonds and help generate the three-dimensional structure of the EGF repeat. A subset of EGF repeats harbor consensus sequences for the addition of one or more specific O-glycans, which are initiated by O-glucose, O-fucose or O-N-acetylglucosamine. These glycans are relatively rare compared to mucin-type O-glycans. However, genetic experiments in model organisms and cell-based assays indicate that at least some of the glycosyltransferases involved in the addition of O-glycans to EGF repeats play important roles in animal development. These studies, combined with state-of-the-art biochemical and structural biology experiments have started to provide an in-depth picture of how these glycans regulate the function of the proteins to which they are linked. In this review, we will discuss the biological roles assigned to EGF repeat O-glycans and the corresponding glycosyltransferases. Since Notch receptors are the best studied proteins with biologically-relevant O-glycans on EGF repeats, a significant part of this review is devoted to the role of these glycans in the regulation of the Notch signaling pathway. We also discuss recently identified proteins other than Notch which depend on EGF repeat glycans to function properly. Several glycosyltransferases involved in the addition or elongation of O-glycans on EGF repeats are mutated in human diseases. Therefore, mechanistic understanding of the functional roles of these carbohydrate modifications is of interest from both basic science and translational perspectives. PMID:26175457

Effects of Stress and Social Enrichment on Alcohol Intake, Biological and Psychological Stress Responses in Rats

DTIC Science & Technology

2010-06-28

Variance (ANOVA) Table for Serum Corticosterone Table 15 – Repeated-Measures ANOVA Table for Body Weight, Within-Subject Effects Table 16...Serum Ethanol Concentration Table 21 – Repeated-Measures ANOVA Table for Rotarod Performance, Within- Subject Effects Table 22 – Repeated...and that this social environment seems to attenuate the effects of predator and unpredictable stressors on serum corticosterone . In summary, stressed

An Ergonomic Evaluation of Aircraft Pilot Seats

NASA Astrophysics Data System (ADS)

Andrade, Yolanda Nicole

Seat comfort has become increasingly important in today's society as we spend more time at consoles, instrument panels, or just online. However, seat comfort is hard to define and difficult to measure. Several measures both objective and subjective were used to evaluate seat comfort in commercially available average pilot seats. Three pilot seats, which had the same material and similar adjustments but different physical attributes, and a universal classroom seat, with different material and no adjustments, were compared by 20 volunteers using subjective and objective measures in a Latin square controlled repeated measures design. A Friedman's test was used to determine that both the comfort questionnaire and the body-map rating results were able to discriminate objective comfort levels between the seats. One-way repeated measures ANOVA tests were used to analyze both the objective tests, actigraph and pressure pad data. All results indicated that one seat was clearly the most comfortable and another, the classroom seat was clearly the most uncomfortable seat. Furthermore, the overall comments per seat were compiled and compared to Fazlollahtabar's 2010) predictive automobile seat comfort theory to determine which factors influence comfort perception. The use of both subjective and objective data can better distinguish comfort from one seat over the other. These results have implications for future tests of seats that will be used for long durations. Limitations and future recommendations are discussed later in the paper. An interesting finding may explain why pressure pad data are typically seemingly at odds with subjective measures of seat comfort.

Upstream mononucleotide A-repeats play a cis-regulatory role in mammals through the DICER1 and Ago proteins.

PubMed

Aporntewan, Chatchawit; Pin-on, Piyapat; Chaiyaratana, Nachol; Pongpanich, Monnat; Boonyaratanakornkit, Viroj; Mutirangura, Apiwat

2013-10-01

A-repeats are the simplest form of tandem repeats and are found ubiquitously throughout genomes. These mononucleotide repeats have been widely believed to be non-functional 'junk' DNA. However, studies in yeasts suggest that A-repeats play crucial biological functions, and their role in humans remains largely unknown. Here, we showed a non-random pattern of distribution of sense A- and T-repeats within 20 kb around transcription start sites (TSSs) in the human genome. Different distributions of these repeats are observed upstream and downstream of TSSs. Sense A-repeats are enriched upstream, whereas sense T-repeats are enriched downstream of TSSs. This enrichment directly correlates with repeat size. Genes with different functions contain different lengths of repeats. In humans, tissue-specific genes are enriched for short repeats of <10 bp, whereas housekeeping genes are enriched for long repeats of ≥10 bp. We demonstrated that DICER1 and Argonaute proteins are required for the cis-regulatory role of A-repeats. Moreover, in the presence of a synthetic polymer that mimics an A-repeat, protein binding to A-repeats was blocked, resulting in a dramatic change in the expression of genes containing upstream A-repeats. Our findings suggest a length-dependent cis-regulatory function of A-repeats and that Argonaute proteins serve as trans-acting factors, binding to A-repeats.

Python-based dynamic scheduling assistant for atmospheric measurements by Bruker instruments using OPUS.

PubMed

Geddes, Alexander; Robinson, John; Smale, Dan

2018-02-01

Atmospheric remote sensing by instruments such as spectrometers and interferometers often requires scheduling that is dependent on external factors, for example; time and solar (or lunar) zenith angle. Such instruments manufactured by Bruker often use the software package OPUS, which, while useful, is not flexible enough for automatic, repeated, atmospheric measurements of this nature. In this brief paper, we describe ASAP, a Python tool developed to run our network of Fourier transform interferometers in New Zealand and Antarctica. It allows the automated scheduling of measurements by time, lunar, or solar zenith angle while accounting for weather or other external parameters. There is a wide range of useful functions, all packaged in a simple graphical user interface; it is available on request.

What to do on spring break? The role of predicted, on-line, and remembered experience in future choice.

PubMed

Wirtz, Derrick; Kruger, Justin; Napa Scollon, Christie; Diener, Ed

2003-09-01

When individuals choose future activities on the basis of their past experiences, what guides those choices? The present study compared students' predicted, on-line, and remembered spring-break experiences, as well as the influence of these factors on students' desire to take a similar vacation in the future. Predicted and remembered experiences were both more positive-and, paradoxically, more negative-than on-line experiences. Of key importance, path analyses revealed that remembered experience, but neither on-line nor anticipated experience, directly predicted the desire to repeat the experience. These results suggest that although on-line measures may be superior to retrospective measures for approximating objective experience, retrospective measures may be superior for predicting choice.

StaRProtein, A Web Server for Prediction of the Stability of Repeat Proteins

PubMed Central

Xu, Yongtao; Zhou, Xu; Huang, Meilan

2015-01-01

Repeat proteins have become increasingly important due to their capability to bind to almost any proteins and the potential as alternative therapy to monoclonal antibodies. In the past decade repeat proteins have been designed to mediate specific protein-protein interactions. The tetratricopeptide and ankyrin repeat proteins are two classes of helical repeat proteins that form different binding pockets to accommodate various partners. It is important to understand the factors that define folding and stability of repeat proteins in order to prioritize the most stable designed repeat proteins to further explore their potential binding affinities. Here we developed distance-dependant statistical potentials using two classes of alpha-helical repeat proteins, tetratricopeptide and ankyrin repeat proteins respectively, and evaluated their efficiency in predicting the stability of repeat proteins. We demonstrated that the repeat-specific statistical potentials based on these two classes of repeat proteins showed paramount accuracy compared with non-specific statistical potentials in: 1) discriminate correct vs. incorrect models 2) rank the stability of designed repeat proteins. In particular, the statistical scores correlate closely with the equilibrium unfolding free energies of repeat proteins and therefore would serve as a novel tool in quickly prioritizing the designed repeat proteins with high stability. StaRProtein web server was developed for predicting the stability of repeat proteins. PMID:25807112

Repeated pregnancy among women with known HIV status in Pune, India.

PubMed

Suryavanshi, Nishi; Erande, Ashwini; Pisal, Hemlata; Shankar, Anita V; Bhosale, Ramesh A; Bollinger, Robert C; Phadke, Mrudula; Sastry, Jayagowri

2008-10-01

HIV-positive women of reproductive age face challenges in decision making related to pregnancy. Understanding factors influencing repeat pregnancies in women with known HIV status are necessary to guide interventions and counseling strategies to better inform and support them. We compared three groups of women attending a large antenatal clinic in Pune, India. They include: Group A--63 HIV-positive women coming for care for a repeat pregnancy after being diagnosed in a previous pregnancy; Group B--64 HIV-negative (repeat) pregnant women attending this antenatal clinic; and Group C--63 HIV-positive non-pregnant women currently enrolled in an ongoing clinical trial. Comparisons of Group A and B indicate that the likelihood of unplanned repeat pregnancies was significantly higher in HIV-positive (70%) than HIV-negative (36%) women (OR=4.1, CI: 2.0-8.7). Inability to terminate the pregnancy (31%) and familial obligations (40%) appear to be important for continuing the unplanned repeat pregnancy. Despite high reported contraceptive use by HIV-positive women, pregnancies still occurred. Death of their youngest child is an important factor as 21% of HIV-positive pregnant women lost their youngest child compared with 3% of HIV-negative women and 3% of HIV-positive non-pregnant women (p<0.001). Repeat pregnancies were more likely to occur for women who did not disclose their HIV status to their spouse. Thus the majority of the repeat pregnancies for HIV-positive women were both unplanned and unwanted.

Neural Plasticity Associated with Hippocampal PKA-CREB and NMDA Signaling Is Involved in the Antidepressant Effect of Repeated Low Dose of Yueju Pill on Chronic Mouse Model of Learned Helplessness

PubMed Central

Zou, Zhilu; Chen, Yin; Shen, Qinqin; Guo, Xiaoyan; Zhang, Yuxuan

2017-01-01

Yueju pill is a traditional Chinese medicine formulated to treat syndromes of mood disorders. Here, we investigated the therapeutic effect of repeated low dose of Yueju in the animal model mimicking clinical long-term depression condition and the role of neural plasticity associated with PKA- (protein kinase A-) CREB (cAMP response element binding protein) and NMDA (N-methyl-D-aspartate) signaling. We showed that a single low dose of Yueju demonstrated antidepressant effects in tests of tail suspension, forced swim, and novelty-suppressed feeding. A chronic learned helplessness (LH) protocol resulted in a long-term depressive-like condition. Repeated administration of Yueju following chronic LH remarkably alleviated all of depressive-like symptoms measured, whereas conventional antidepressant fluoxetine only showed a minor improvement. In the hippocampus, Yueju and fluoxetine both normalized brain-derived neurotrophic factor (BDNF) and PKA level. Only Yueju, not fluoxetine, rescued the deficits in CREB signaling. The chronic LH upregulated the expression of NMDA receptor subunits NR1, NR2A, and NR2B, which were all attenuated by Yueju. Furthermore, intracerebraventricular administration of NMDA blunted the antidepressant effect of Yueju. These findings supported the antidepressant efficacy of repeated routine low dose of Yueju in a long-term depression model and the critical role of CREB and NMDA signaling. PMID:29075536

Neural Plasticity Associated with Hippocampal PKA-CREB and NMDA Signaling Is Involved in the Antidepressant Effect of Repeated Low Dose of Yueju Pill on Chronic Mouse Model of Learned Helplessness.

PubMed

Zou, Zhilu; Chen, Yin; Shen, Qinqin; Guo, Xiaoyan; Zhang, Yuxuan; Chen, Gang

2017-01-01

Yueju pill is a traditional Chinese medicine formulated to treat syndromes of mood disorders. Here, we investigated the therapeutic effect of repeated low dose of Yueju in the animal model mimicking clinical long-term depression condition and the role of neural plasticity associated with PKA- (protein kinase A-) CREB (cAMP response element binding protein) and NMDA (N-methyl-D-aspartate) signaling. We showed that a single low dose of Yueju demonstrated antidepressant effects in tests of tail suspension, forced swim, and novelty-suppressed feeding. A chronic learned helplessness (LH) protocol resulted in a long-term depressive-like condition. Repeated administration of Yueju following chronic LH remarkably alleviated all of depressive-like symptoms measured, whereas conventional antidepressant fluoxetine only showed a minor improvement. In the hippocampus, Yueju and fluoxetine both normalized brain-derived neurotrophic factor (BDNF) and PKA level. Only Yueju, not fluoxetine, rescued the deficits in CREB signaling. The chronic LH upregulated the expression of NMDA receptor subunits NR1, NR2A, and NR2B, which were all attenuated by Yueju. Furthermore, intracerebraventricular administration of NMDA blunted the antidepressant effect of Yueju. These findings supported the antidepressant efficacy of repeated routine low dose of Yueju in a long-term depression model and the critical role of CREB and NMDA signaling.

Using one-dimensional waveguide resonators to measure phase velocities in bubbly liquids.

PubMed

Dolder, Craig N; Wilson, Preston S

2017-04-01

Resonator techniques can be successfully used to extract effective medium properties from dispersive materials. However, in some cases the dispersion can cause modes to repeat. If repeated modes are not taken into account, the useful range of the resonator technique is limited. A resonance tube containing tethered balloons is used to create a dispersive effective medium. Resonator measurements show that modes do repeat. Direct measurement of the mode shapes allows exploitation of all longitudinal radially symmetric modes and expands the frequency range of the technique. A theoretical model is also used to predict when modes repeat. For the presented data set this method increases the measurement range from below 160 Hz to 3000 Hz excluding the stop band where resonances are damped. A means to account for non-ideal resonator boundary conditions often found in highly dispersive systems is discussed.

Cerebral Small Vessel Disease Burden Is Associated with Motor Performance of Lower and Upper Extremities in Community-Dwelling Populations

PubMed Central

Su, Ning; Zhai, Fei-Fei; Zhou, Li-Xin; Ni, Jun; Yao, Ming; Li, Ming-Li; Jin, Zheng-Yu; Gong, Gao-Lang; Zhang, Shu-Yang; Cui, Li-Ying; Tian, Feng; Zhu, Yi-Cheng

2017-01-01

Objective: To investigate the correlation between cerebral small vessel disease (CSVD) burden and motor performance of lower and upper extremities in community-dwelling populations. Methods: We performed a cross-sectional analysis on 770 participants enrolled in the Shunyi study, which is a population-based cohort study. CSVD burden, including white matter hyperintensities (WMH), lacunes, cerebral microbleeds (CMBs), perivascular spaces (PVS), and brain atrophy were measured using 3T magnetic resonance imaging. All participants underwent quantitative motor assessment of lower and upper extremities, which included 3-m walking speed, 5-repeat chair-stand time, 10-repeat pronation–supination time, and 10-repeat finger-tapping time. Data on demographic characteristics, vascular risk factors, and cognitive functions were collected. General linear model analysis was performed to identify potential correlations between motor performance measures and imaging markers of CSVD after controlling for confounding factors. Results: For motor performance of the lower extremities, WMH was negatively associated with gait speed (standardized β = -0.092, p = 0.022) and positively associated with chair-stand time (standardized β = 0.153, p < 0.0001, surviving FDR correction). For motor performance of the upper extremities, pronation–supination time was positively associated with WMH (standardized β = 0.155, p < 0.0001, surviving FDR correction) and negatively with brain parenchymal fraction (BPF; standardized β = -0.125, p = 0.011, surviving FDR correction). Only BPF was found to be negatively associated with finger-tapping time (standardized β = -0.123, p = 0.012). However, lacunes, CMBs, or PVS were not found to be associated with motor performance of lower or upper extremities in multivariable analysis. Conclusion: Our findings suggest that cerebral microstructural changes related to CSVD may affect motor performance of both lower and upper extremities. WMH and brain atrophy are most strongly associated with motor function deterioration in community-dwelling populations. PMID:29021757

Cerebral Small Vessel Disease Burden Is Associated with Motor Performance of Lower and Upper Extremities in Community-Dwelling Populations.

PubMed

Su, Ning; Zhai, Fei-Fei; Zhou, Li-Xin; Ni, Jun; Yao, Ming; Li, Ming-Li; Jin, Zheng-Yu; Gong, Gao-Lang; Zhang, Shu-Yang; Cui, Li-Ying; Tian, Feng; Zhu, Yi-Cheng

2017-01-01

Objective: To investigate the correlation between cerebral small vessel disease (CSVD) burden and motor performance of lower and upper extremities in community-dwelling populations. Methods: We performed a cross-sectional analysis on 770 participants enrolled in the Shunyi study, which is a population-based cohort study. CSVD burden, including white matter hyperintensities (WMH), lacunes, cerebral microbleeds (CMBs), perivascular spaces (PVS), and brain atrophy were measured using 3T magnetic resonance imaging. All participants underwent quantitative motor assessment of lower and upper extremities, which included 3-m walking speed, 5-repeat chair-stand time, 10-repeat pronation-supination time, and 10-repeat finger-tapping time. Data on demographic characteristics, vascular risk factors, and cognitive functions were collected. General linear model analysis was performed to identify potential correlations between motor performance measures and imaging markers of CSVD after controlling for confounding factors. Results: For motor performance of the lower extremities, WMH was negatively associated with gait speed (standardized β = -0.092, p = 0.022) and positively associated with chair-stand time (standardized β = 0.153, p < 0.0001, surviving FDR correction). For motor performance of the upper extremities, pronation-supination time was positively associated with WMH (standardized β = 0.155, p < 0.0001, surviving FDR correction) and negatively with brain parenchymal fraction (BPF; standardized β = -0.125, p = 0.011, surviving FDR correction). Only BPF was found to be negatively associated with finger-tapping time (standardized β = -0.123, p = 0.012). However, lacunes, CMBs, or PVS were not found to be associated with motor performance of lower or upper extremities in multivariable analysis. Conclusion: Our findings suggest that cerebral microstructural changes related to CSVD may affect motor performance of both lower and upper extremities. WMH and brain atrophy are most strongly associated with motor function deterioration in community-dwelling populations.

Military mental health: the role of daily hassles while deployed.

PubMed

Heron, Elizabeth A; Bryan, Craig J; Dougherty, Craig A; Chapman, William G

2013-12-01

This study sought to identify factors contributing to symptoms of depression and posttraumatic stress disorder (PTSD) in recently deployed combat veterans. A sample of 168 active duty military personnel completed measures of combat exposure, deployment-related daily hassles, depression symptoms, and PTSD symptoms at six time points across their deployment: predeployment and 1, 3, 6, and 12 months postdeployment. Mixed-effects linear modeling with repeated measures was used to identify factors associated with depression and PTSD severity over time. Postdeployment depression severity did not change over time, but PTSD severity decreased slightly over time after returning home. Postdeployment depression severity was predicted by past (but not recent) combat exposure, daily hassles, and concurrent PTSD symptoms. Postdeployment PTSD severity was predicted by past and recent combat exposure, concurrent depression symptoms, and male sex. Depression severity mediated the relationship between daily hassles and postdeployment PTSD severity.

Repeatability study of replicate crash tests: A signal analysis approach.

PubMed

Seppi, Jeremy; Toczyski, Jacek; Crandall, Jeff R; Kerrigan, Jason

2017-10-03

To provide an objective basis on which to evaluate the repeatability of vehicle crash test methods, a recently developed signal analysis method was used to evaluate correlation of sensor time history data between replicate vehicle crash tests. The goal of this study was to evaluate the repeatability of rollover crash tests performed with the Dynamic Rollover Test System (DRoTS) relative to other vehicle crash test methods. Test data from DRoTS tests, deceleration rollover sled (DRS) tests, frontal crash tests, frontal offset crash tests, small overlap crash tests, small overlap impact (SOI) crash tests, and oblique crash tests were obtained from the literature and publicly available databases (the NHTSA vehicle database and the Insurance Institute for Highway Safety TechData) to examine crash test repeatability. Signal analysis of the DRoTS tests showed that force and deformation time histories had good to excellent repeatability, whereas vehicle kinematics showed only fair repeatability due to the vehicle mounting method for one pair of tests and slightly dissimilar mass properties (2.2%) in a second pair of tests. Relative to the DRS, the DRoTS tests showed very similar or higher levels of repeatability in nearly all vehicle kinematic data signals with the exception of global X' (road direction of travel) velocity and displacement due to the functionality of the DRoTS fixture. Based on the average overall scoring metric of the dominant acceleration, DRoTS was found to be as repeatable as all other crash tests analyzed. Vertical force measures showed good repeatability and were on par with frontal crash barrier forces. Dynamic deformation measures showed good to excellent repeatability as opposed to poor repeatability seen in SOI and oblique deformation measures. Using the signal analysis method as outlined in this article, the DRoTS was shown to have the same or better repeatability of crash test methods used in government regulatory and consumer evaluation test protocols.

Comparison of Repeatability and Agreement between Swept-Source Optical Biometry and Dual-Scheimpflug Topography.

PubMed

Jung, Soyeon; Chin, Hee Seung; Kim, Na Rae; Lee, Kang Won; Jung, Ji Won

2017-01-01

To assess the repeatability and agreement of parameters obtained with two biometers and to compare the predictability. Biometry was performed on 101 eyes with cataract using the IOLMaster 700 and the Galilei G6. Three measurements were obtained per eye with each device, and repeatability was evaluated. The axial length (AL), anterior chamber depth (ACD), keratometry (K), white-to-white (WTW) corneal diameter, central corneal thickness (CCT), and lens thickness (LT) were measured and postoperative predictability was compared. Measurements could not be obtained with the IOLMaster 700 in one eye and in seven eyes with the Galilei G6 due to dense cataract. Both the IOLMaster 700 and Galilei G6 showed good repeatability, although the IOLMaster 700 showed better repeatability than the Galilei G6. There were no statistically significant differences in AL, ACD, steepest K, WTW, and LT ( P > 0.050), although flattest K, mean K, and CCT differed ( P < 0.050). The proportion of eyes with an absolute prediction error within 0.5 D was 85.0% for the IOLMaster 700 and was 80.0% for the Galilei G6 based on the SRK/T formula. Two biometers showed high repeatability and relatively good agreements. The swept-source optical biometer demonstrated better repeatability, penetration, and an overall lower prediction error.

A novel magnet based 3D printed marker wand as basis for repeated in-shoe multi segment foot analysis: a proof of concept.

PubMed

Eerdekens, Maarten; Staes, Filip; Pilkington, Thomas; Deschamps, Kevin

2017-01-01

Application of in-shoe multi-segment foot kinematic analyses currently faces a number of challenges, including: (i) the difficulty to apply regular markers onto the skin, (ii) the necessity for an adequate shoe which fits various foot morphologies and (iii) the need for adequate repeatability throughout a repeated measure condition. The aim of this study therefore was to design novel magnet based 3D printed markers for repeated in-shoe measurements while using accordingly adapted modified shoes for a specific multi-segment foot model. Multi-segment foot kinematics of ten participants were recorded and kinematics of hindfoot, midfoot and forefoot were calculated. Dynamic trials were conducted to check for intra and inter-session repeatability when combining novel markers and modified shoes in a repeated measures design. Intraclass correlation coefficients were calculated to determine reliability. Both repeatability and reliability were proven to be good to excellent with maximum joint angle deviations of 1.11° for intra-session variability and 1.29° for same-day inter-session variability respectively and ICC values of >0.91. The novel markers can be reliably used in future research settings using in-shoe multi-segment foot kinematic analyses with multiple shod conditions.

Factors predicting change in hospital safety climate and capability in a multi-site patient safety collaborative: a longitudinal survey study.

PubMed

Benn, Jonathan; Burnett, Susan; Parand, Anam; Pinto, Anna; Vincent, Charles

2012-07-01

The study had two specific objectives: (1) To analyse change in a survey measure of organisational patient safety climate and capability (SCC) resulting from participation in the UK Safer Patients Initiative and (2) To investigate the role of a range of programme and contextual factors in predicting change in SCC scores. Single group longitudinal design with repeated measurement at 12-month follow-up. Multiple service areas within NHS hospital sites across England, Wales, Scotland and Northern Ireland. Stratified sample of 284 respondents representing programme teams at 19 hospital sites. A complex intervention comprising a multi-component quality improvement collaborative focused upon patient safety and designed to impact upon hospital leadership, communication, organisation and safety climate. A survey including a 31-item SCC scale was administered at two time-points. Modest but significant positive movement in SCC score was observed between the study time-points. Individual programme responsibility, availability of early adopters, multi-professional collaboration and extent of process measurement were significant predictors of change in SCC. Hospital type and size, along with a range of programme preconditions, were not found to be significant. A range of social, cultural and organisational factors may be sensitive to this type of intervention but the measurable effect is small. Supporting critical local programme implementation factors may be an effective strategy in achieving development in organisational patient SCC, regardless of contextual factors and organisational preconditions.

The Boston Keratoprosthesis: Comparing Corneal Epithelial Cell Compatibility with Titanium and PMMA

PubMed Central

Ament, Jared D.; Spurr-Michaud, Sandra J.; Dohlman, Claes H.; Gipson, Ilene K.

2014-01-01

Purpose To determine in vitro whether titanium is superior in corneal cell compatibility to standard polymethyl-methacrylate (PMMA) for the Boston Keratoprosthesis (KPro). Methods Human corneal-limbal epithelial (HCLE) cells were cultured 24, 48, 72, 96, 120, 144, or 168 hours in culture plates alone (controls) or with PMMA or titanium discs. Experiments were performed in triplicate and repeated (final n = 6). To determine if a soluble, toxic factor is emitted from materials, concurrent experiments at 48 and 144 hours were performed with discs placed in Transwell Supports, with HCLE cells plated beneath. As an additional test for soluble factors, cells were incubated 24 hours with disc-conditioned media, and number of viable cells per well was quantified at each timepoint by proliferation assay. To determine if delayed cell proliferation was attributable to cell death, HCLE cell death was measured under all conditions and quantified at each timepoint by cytotoxicity assay. The effects of material on HCLE cell proliferation over time was determined by repeated measures ANOVA. P < 0.05 was statistically significant. Results HCLE cell proliferation was greater in wells with titanium discs compared to PMMA. Differences between the test discs and control non-disc cocultures were statistically significant over time for both cell proliferation (P = 0.001) and death (P = 0.0025). No significant difference was found using Transwells (P = 0.9836) or disc-conditioned media (P = 0.36). Conclusion This in vitro HCLE cell model demonstrates significantly increased cell proliferation and decreased cell death with cell/titanium contact compared to cell/PMMA contact. Moreover, differences are unlikely attributable to a soluble factor. Prospective in vivo analysis of the two KPro biomaterials is indicated. PMID:19574903

Population Fisher information matrix and optimal design of discrete data responses in population pharmacodynamic experiments.

PubMed

Ogungbenro, Kayode; Aarons, Leon

2011-08-01

In the recent years, interest in the application of experimental design theory to population pharmacokinetic (PK) and pharmacodynamic (PD) experiments has increased. The aim is to improve the efficiency and the precision with which parameters are estimated during data analysis and sometimes to increase the power and reduce the sample size required for hypothesis testing. The population Fisher information matrix (PFIM) has been described for uniresponse and multiresponse population PK experiments for design evaluation and optimisation. Despite these developments and availability of tools for optimal design of population PK and PD experiments much of the effort has been focused on repeated continuous variable measurements with less work being done on repeated discrete type measurements. Discrete data arise mainly in PDs e.g. ordinal, nominal, dichotomous or count measurements. This paper implements expressions for the PFIM for repeated ordinal, dichotomous and count measurements based on analysis by a mixed-effects modelling technique. Three simulation studies were used to investigate the performance of the expressions. Example 1 is based on repeated dichotomous measurements, Example 2 is based on repeated count measurements and Example 3 is based on repeated ordinal measurements. Data simulated in MATLAB were analysed using NONMEM (Laplace method) and the glmmML package in R (Laplace and adaptive Gauss-Hermite quadrature methods). The results obtained for Examples 1 and 2 showed good agreement between the relative standard errors obtained using the PFIM and simulations. The results obtained for Example 3 showed the importance of sampling at the most informative time points. Implementation of these expressions will provide the opportunity for efficient design of population PD experiments that involve discrete type data through design evaluation and optimisation.

Rasch analysis and impact factor methods both yield valid and comparable measures of health status in interstitial lung disease.

PubMed

Patel, Amit S; Siegert, Richard J; Bajwah, Sabrina; Brignall, Kate; Gosker, Harry R; Moxham, John; Maher, Toby M; Renzoni, Elisabetta A; Wells, Athol U; Higginson, Irene J; Birring, Surinder S

2015-09-01

Rasch analysis has largely replaced impact factor methodology for developing health status measures. The aim of this study was to develop a health status questionnaire for patients with interstitial lung disease (ILD) using impact factor methodology and to compare its validity with that of another version developed using Rasch analysis. A preliminary 71-item questionnaire was developed and evaluated in 173 patients with ILD. Items were reduced by the impact factor method (King's Brief ILD questionnaire, KBILD-I) and Rasch analysis (KBILD-R). Both questionnaires were validated by assessing their relationship with forced vital capacity (FVC) and St Georges Respiratory Questionnaire (SGRQ) and by evaluating internal reliability, repeatability, and longitudinal responsiveness. The KBILD-R and KBILD-I comprised 15 items each. The content of eight items differed between the KBILD-R and KBILD-I. Internal and test-retest reliability was good for total scores of both questionnaires. There was a good relationship with SGRQ and moderate relationship with FVC for both questionnaires. Effect sizes were comparable. Both questionnaires discriminated patients with differing disease severity. Despite considerable differences in the content of retained items, both KBILD-R and KBILD-I questionnaires demonstrated acceptable measurement properties and performed comparably in a clinical setting. Copyright © 2015 Elsevier Inc. All rights reserved.

Repetition of intentional drug overdose: a population-based study.

PubMed

Finkelstein, Yaron; Macdonald, Erin M; Hollands, Simon; Sivilotti, Marco L A; Hutson, Janine R; Mamdani, Muhammad M; Koren, Gideon; Juurlink, David N

2016-08-01

Intentional overdose is a leading method of self-harm and suicide, and repeat attempts strongly predict eventual death by suicide. To determine the risk of recurrence after a first intentional overdose. Secondary objectives included characterization of the temporal course and potential predictors of repeat overdose, a strong risk factor for death from suicide. Population-based cohort study. Ontario, Canada, from 1 April 2002 to 31 March 2013. All Ontario residents presenting to an emergency department after a first intentional overdose. The incidence and timing of recurrent overdose. We followed 81,675 patients discharged from hospital after a first intentional overdose. Overall, 13,903 (17.0%) returned with a repeat overdose after a median interval of 288 (inter-quartile range: 62 to 834) days. Of these, 4493 (5.5%) had multiple repeat episodes. Factors associated with repeat self-poisoning included psychiatric care in the preceding year (adjusted hazard ratio [aHR] 1.55; 95% confidence interval [CI] 1.50 to 1.61), alcohol dependence (aHR 1.41; 95% CI 1.35 to 1.46) and documented depression (aHR 1.39; 95% CI 1.34 to 1.44). Female sex, rural residence, lower socioeconomic status, ingestion of psychoactive drugs and younger age were also weakly associated with repeat overdose. Hospital presentation for repetition of intentional overdose is common, with recurrent episodes often far removed from the first. While several factors predict overdose repetition, none is particularly strong. Secondary prevention initiatives should be implemented for all individuals who present to the emergency department and survive intentional overdose.

Acute exercise attenuates negative affect following repeated sad mood inductions in persons who have recovered from depression.

PubMed

Mata, Jutta; Hogan, Candice L; Joormann, Jutta; Waugh, Christian E; Gotlib, Ian H

2013-02-01

Identifying factors that may protect individuals from developing Major Depressive Disorder (MDD) in the face of stress is critical. In the current study we experimentally tested whether such a potentially protective factor, engaging in acute exercise, reduces the adverse effects of repeated sad mood inductions in individuals who have recovered from depression. We hypothesized that recovered depressed participants who engage in acute exercise report a smaller increase in negative affect (NA) and a smaller decrease in positive affect (PA) when exposed to a repeated sad mood induction (i.e., habituation), whereas participants who do not exercise show sensitization (i.e., increased NA and decreased PA in response to a repeated adverse stimulus). Forty-one women recovered from MDD and 40 healthy control women were randomly assigned to either exercise for 15 minutes or quiet rest. Afterward, participants were exposed to two sad mood inductions and reported their levels of affect throughout the study. Recovered depressed participants who had not exercised exhibited higher NA after the second sad mood induction, a finding consistent with sensitization. In contrast, both recovered depressed participants who had engaged in acute exercise and healthy control participants showed no increase in NA in response to the repeated sad mood induction. Participants who exercised reported higher PA after the exercise bout; however, our hypothesis concerning reported PA trajectories following the sad mood inductions was not supported. Results suggest that exercise can serve as a protective factor in the face of exposure to repeated emotional stressors, particularly concerning NA in individuals who have recovered from depression. 2013 APA, all rights reserved

Influence of radiographic techniques on the measurement of femoral anteversion angles and a conformation score of pelvic limbs in Labrador retrievers.

PubMed

Mostafa, Ayman A; Cunningham, Devin P; Boudrieau, Randy J; Kowaleski, Michael P; Griffon, Dominique J

2018-04-01

To determine repeatability of and correlation between 2 radiographic measurements of femoral anteversion angles (FAA) and to determine their influence on a score derived from tibial plateau angle (TPA) and FAA to predict the risk of cranial cruciate ligament disease (CCLD). Prospective clinical study. Forty-eight Labrador retrievers with or without CCLD. FAA and CCLD scores were calculated for each limb from extended pelvic radiographs (t-FAA) or angled (a-FAA) projections of the femur by 3 investigators. One investigator repeated measurements twice. Data were analyzed for repeatability, correlation between t-FAA and a-FAA, and their influence on CCLD scores. FAA correlated most strongly with the distance between the femoral head and the femoral axis on mediolateral radiographs, a measurement with excellent repeatability. t-FAA and a-FAA correlated with each other (r > 0.79, P < .0001), although t-FAA were about 1° greater than a-FAA (P = .01). Intrainvestigator and interinvestigator repeatability of the CCLD score was fair when derived from t-FAA and good to excellent when derived from a-FAA. CCLD scores differed between radiographic techniques but led to different predictions in only 9 (10%) limbs, all with lower TPA and CCLD scores than the rest of the population. a-FAA correlated strongly with t-FAA and improved the repeatability of CCLD scores within and between investigators. A craniocaudal angled beam projection of the femur is a suitable alternative to a ventrodorsal pelvic radiograph when measuring FAA and may improve the repeatability and positive predictive value of CCLD scores. © 2018 The American College of Veterinary Surgeons.

Repeatability of standard metabolic rate (SMR) in a small fish, the spined loach (Cobitis taenia).

PubMed

Maciak, Sebastian; Konarzewski, Marek

2010-10-01

Significant repeatability of a trait of interest is an essential assumption for undertaking studies of phenotypic variability. It is especially important in studies on highly variable traits, such as metabolic rates. Recent publications suggest that resting/basal metabolic rate of homeotherms is repeatable across wide range of species. In contrast, studies on the consistency of standard metabolic rate (SMR) in ectotherms, particularly fish, are scarce. Here we present a comprehensive analysis of several important technical aspects of body mass-corrected SMR measurements and its repeatability in a small (average weight approximately 3g) fish, the spined loach (Cobitis taenia). First we demonstrated that release of oxygen from the walls of metabolic chambers exposed to hypoxic conditions did not confound SMR measurements. Next, using principle of propagation of measurement uncertainties we demonstrated that in aquatic systems, measurement error is significantly higher in open than closed respirometry setups. The measurement error for SMR of a small fish determined in a closed aquatic system is comparable to that obtainable using top-notch open-flow systems used for air-breathing terrestrial animals. Using a closed respirometer we demonstrated that body mass-corrected SMR in spined loaches was repeatable under both normoxia and hypoxia over a 5-month period (Pearson correlation r=0.68 and r=0.73, respectively) as well as across both conditions (intraclass correlation coefficient tau=0.30). In these analyses we accounted for possible effect of oxygen consumption of the oxygen electrode on repeatability of SMR. Significant SMR consistency was accompanied by significant repeatability of body mass (intraclass correlation coefficient tau=0.86). To our knowledge, this is the first study showing long-term repeatability of body mass and SMR in a small fish, and is consistent with the existence of heritable variation of these two traits. 2010 Elsevier Inc. All rights reserved.

Does personality in small rodents vary depending on population density?

PubMed

Korpela, Katri; Sundell, Janne; Ylönen, Hannu

2011-01-01

Personality means an individual's unique way of behaving and reacting to the environment. It is a stable and heritable trait, which is expressed consistently in different situations. The aim of our study was to develop novel tests to depict the personality structure of the bank vole Myodes glareolus, and to determine if the phase of the population cycle, i.e. population density, affects personality. We focused on some central aspects of bank vole behaviour: mobility, risk taking, exploratory behaviour, dominance, and aggressive behaviour towards pups. These behaviours were chosen because they directly affect bank vole survival or fitness or are classified as important factors of personality in other species. In total, 192 males from different populations went through four behavioural tests, in which 20 variables were measured. The tests were repeated after 3 weeks, which verified that all traits were stable, i.e. repeatable between trials. Three personality compounds emerged, named extroversion, novelty seeking and infanticide. Extroversion included dominance and mobility, while novelty seeking consisted of risk taking and exploration. Infanticide encompassed all indices measuring harmful behaviour towards pups. Mobility and dominance were connected, possibly because both seem to depend on condition. Time spent in captivity increased extroversion, which may be explained by good food, stable conditions and acclimation to strong social cues. Novelty seeking was connected to repeatability which could mean that novelty avoiding individuals adjust their behaviour to match new environments. Population density affected the infanticide trait but not novelty seeking or extroversion.

Longitudinal Assessment of Effort-Reward Imbalance and Job Strain Across Pregnancy: A Preliminary Study.

PubMed

Meyer, John D; Muntaner, Carles; O'Campo, Patricia; Warren, Nicolas

2016-07-01

To assess longitudinal changes in occupational effort-reward imbalance (ERI) and demand-control (DC) scores across pregnancy and examine associations with blood pressure (BP) during pregnancy. A pilot repeated-measures survey was administered four times to a sample of working women across pregnancy using the ERI and DC instruments. Demographic data and blood pressure measurements were collected at each interval. Growth mixture modeling was used to examine trajectories of change in occupational characteristics. Associations with BP were examined using repeated-measures linear regression models. ERI model components (effort, reward, and overcommitment) all declined across pregnancy while job control remained stable. Increasing ERI trajectory was associated with higher systolic BP (b = 8.8; p < 0.001) as was high overcommitment; declining ERI also showed a lesser association with higher BP. Associations between DC trajectories and BP were much smaller, and non-significant once controlled for overcommitment. Self-assessed efforts, rewards, and overcommitment at work decline across pregnancy in our participants, while job control remains stable. Replication in a more diverse pregnant working population is warranted to confirm these results. These preliminary data suggest that further investigation into the factors that may be linked with improved work psychosocial climate during pregnancy may be useful in order to improve pregnancy outcomes.

Longitudinal assessment of effort-reward imbalance and job strain across pregnancy: A preliminary study

PubMed Central

Meyer, John D; Muntaner, Carles; O'Campo, Patricia; Warren, Nicolas

2016-01-01

Objectives To assess longitudinal changes in occupational effort-reward imbalance (ERI) and demand-control (DC) scores across pregnancy and examine associations with blood pressure (BP) during pregnancy. Methods A pilot repeated-measures survey was administered four times to a sample of working women across pregnancy using the ERI and DC instruments. Demographic data and blood pressure measurements were collected at each interval. Growth mixture modeling was used to examine trajectories of change in occupational characteristics. Associations with BP were examined using repeated-measures linear regression models. Results ERI model components (effort, reward, and overcommitment) all declined across pregnancy while job control remained stable. Increasing ERI trajectory was associated with higher systolic BP (b=8.8; p<0.001) as was high overcommitment; declining ERI also showed a smaller association with higher BP. Associations between DC trajectories and BP were much smaller, and non-significant once controlled for overcommitment. Conclusions Self-assessed efforts, rewards, and overcommitment at work decline across pregnancy in our participants, while job control remains stable. Replication in a more diverse pregnant working population is warranted to confirm these results. These preliminary data suggest that further investigation into the factors that may be linked with improved work psychosocial climate during pregnancy may be useful in order to improve pregnancy outcomes. PMID:26948376

In Vitro Expansion of CAG, CAA, and Mixed CAG/CAA Repeats.

PubMed

Figura, Grzegorz; Koscianska, Edyta; Krzyzosiak, Wlodzimierz J

2015-08-11

Polyglutamine diseases, including Huntington's disease and a number of spinocerebellar ataxias, are caused by expanded CAG repeats that are located in translated sequences of individual, functionally-unrelated genes. Only mutant proteins containing polyglutamine expansions have long been thought to be pathogenic, but recent evidence has implicated mutant transcripts containing long CAG repeats in pathogenic processes. The presence of two pathogenic factors prompted us to attempt to distinguish the effects triggered by mutant protein from those caused by mutant RNA in cellular models of polyglutamine diseases. We used the SLIP (Synthesis of Long Iterative Polynucleotide) method to generate plasmids expressing long CAG repeats (forming a hairpin structure), CAA-interrupted CAG repeats (forming multiple unstable hairpins) or pure CAA repeats (not forming any secondary structure). We successfully modified the original SLIP protocol to generate repeats of desired length starting from constructs containing short repeat tracts. We demonstrated that the SLIP method is a time- and cost-effective approach to manipulate the lengths of expanded repeat sequences.

Large Polyglutamine Repeats Cause Muscle Degeneration in SCA17 Mice

PubMed Central

Huang, Shanshan; Yang, Su; Guo, Jifeng; Yan, Sen; Gaertig, Marta A.; Li, Shihua; Li, Xiao-Jiang

2015-01-01

SUMMARY In polyglutamine (polyQ) diseases, large polyQ repeats cause juvenile cases with different symptoms than adult-onset patients, who carry smaller expanded polyQ repeats. The mechanisms behind the differential pathology mediated by different polyQ repeat lengths remain unknown. By studying knock-in mouse models of spinal cerebellar ataxia-17 (SCA17), we found that a large polyQ (105 glutamines) in the TATA box-binding protein (TBP) preferentially causes muscle degeneration and reduces the expression of muscle-specific genes. Direct expression of TBP with different polyQ repeats in mouse muscle revealed that muscle degeneration is mediated only by the large polyQ repeats. Different polyQ repeats differentially alter TBP’s interaction with neuronal and muscle-specific transcription factors. As a result, the large polyQ repeat decreases the association of MyoD with TBP and DNA promoters. Our findings suggest that specific alterations in protein interactions by large polyQ repeats may account for the unique pathology in juvenile polyQ diseases. PMID:26387956

Serum organochlorine pesticide residues and risk of testicular germ cell carcinoma: a population-based case-control study.

PubMed

Biggs, Mary L; Davis, Mark D; Eaton, David L; Weiss, Noel S; Barr, Dana B; Doody, David R; Fish, Sherianne; Needham, Larry L; Chen, Chu; Schwartz, Stephen M

2008-08-01

Testicular germ cell carcinoma (TGCC) is the most common malignancy among men ages 20 to 34 years. Although the pathogenesis of TGCC is poorly understood, suboptimal androgen levels or impaired androgen signaling may play a role. Some persistent organochlorine pesticides commonly found in human tissue possess antiandrogenic properties. We examined whether the risk of TGCC is associated with serum levels of 11 organochlorine pesticides, including p,p'-DDE, and whether the p,p'-DDE-TGCC association is modified by CAG or GGN repeat polymorphisms in the androgen receptor gene. We conducted a population-based case-control study among 18- to 44-year-old male residents of three Washington State counties. Cases (n = 246) were diagnosed during 1999 to 2003 with a first, primary TGCC. Controls (n = 630) were men of similar age with no history of TGCC from the same population identified through random-digit telephone dialing. Questionnaires elicited information on demographic, medical, and lifestyle factors. A blood specimen provided serum for gas chromatography-high-resolution mass spectrometry analysis of organochlorine pesticide residues and DNA for genotyping. We observed no clear patterns between TGCC risk and concentrations of any of the organochlorines measured, nor did we observe that the risk associated with p,p'-DDE was modified by androgen receptor CAG (<23 versus > or =23 repeats) or GGN (<17 versus > or =17 repeats) genotype. This study does not provide support for the hypothesis that adult exposure to organochlorine pesticides is associated with risk of TGCC. Due to uncertainty regarding how well organochlorine levels measured in adulthood reflect exposures during early life, further research is needed using exposure measurements collected in utero or during infancy.

Agarose coated spherical micro resonator for humidity measurements.

PubMed

Mallik, Arun Kumar; Liu, Dejun; Kavungal, Vishnu; Wu, Qiang; Farrell, Gerald; Semenova, Yuliya

2016-09-19

A new type of fiber optic relative humidity (RH) sensor based on an agarose coated silica microsphere resonator is proposed and experimentally demonstrated. Whispering gallery modes (WGMs) in the micro resonator are excited by evanescent coupling using a tapered fiber with ~3.3 µm waist diameter. A change in the relative humidity of the surrounding the resonator air induces changes in the refractive index (RI) and thickness of the Agarose coating layer. These changes in turn lead to a spectral shift of the WGM resonances, which can be related to the RH value after a suitable calibration. Studies of the repeatability, long-term stability, measurement accuracy and temperature dependence of the proposed sensor are carried out. The RH sensitivity of the proposed sensor depends on the concentration of the agarose gel which determines the initial thickness of the deposited coating layer. Studies of the micro- resonators with coating layers fabricated from gels with three different Agarose concentrations of 0.5%, 1.125% and 2.25 wt./vol.% showed that an increase in the initial thickness of the coating material results in an increase in sensitivity but also leads to a decrease of quality factor (Q) of the micro resonator. The highest sensitivity achieved in our experiments was 518 pm/%RH in the RH range from 30% to 70%. The proposed sensor offers the advantages of a very compact form factor, low hysteresis, good repeatability, and low cross sensitivity to temperature.

From Hipparcos to Gaia

NASA Astrophysics Data System (ADS)

Eyer, L.; Dubath, P.; Saesen, S.; Evans, D. W.; Wyrzykowski, L.; Hodgkin, S.; Mowlavi, N.

2012-04-01

The measurement of the positions, distances, motions and luminosities of stars represents the foundations of modern astronomical knowledge. Launched at the end of the eighties, the ESA Hipparcos satellite was the first space mission dedicated to such measurements. Hipparcos improved position accuracies by a factor of 100 compared to typical ground-based results and provided astrometric and photometric multi-epoch observations of 118,000 stars over the entire sky. The impact of Hipparcos on astrophysics has been extremely valuable and diverse. Building on this important European success, the ESA Gaia cornerstone mission promises an even more impressive advance. Compared to Hipparcos, it will bring a gain of a factor 50 to 100 in position accuracy and of a factor of 10,000 in star number, collecting photometric, spectrophotometric and spectroscopic data for one billion celestial objects. During its 5-year flight, Gaia will measure objects repeatedly, up to a few hundred times, providing an unprecedented database to study the variability of all types of celestial objects. Gaia will bring outstanding contributions, directly or indirectly, to most fields of research in astrophysics, such as the study of our Galaxy and of its stellar constituents, and the search for planets outside the solar system.

The Use of Online Modules and the Effect on Student Outcomes in a High School Chemistry Class

NASA Astrophysics Data System (ADS)

Lamb, Richard L.; Annetta, Len

2013-10-01

The purpose of the study was to review the efficacy of online chemistry simulations in a high school chemistry class and provide discussion of the factors that may affect student learning. The sample consisted of 351 high school students exposed to online simulations. Researchers administered a pretest, intermediate test and posttest to measure chemistry content knowledge acquired during the use of online chemistry laboratory simulations. The authors also analyzed student journal entries as an attitudinal measure of chemistry during the simulation experience. The four analyses conducted were Repeated Time Measures Analysis of Variance, a three-way Analysis of Variance, Logistic Regression and Multiple Analysis of Variance. Each of these analyses provides for a slightly different aspect of factors regarding student attitudes and outcomes. Results indicate that there is a statistically significant main effect across grouping type (experimental versus control, p = 0.042, α = 0.05). Analysis of student journal entries suggests that attitudinal factors may affect student outcomes concerning the use of online supplemental instruction. Implications for this study show that the use of online simulations promotes increased understanding of chemistry content through open-ended and interactive questioning.

A nationwide, population-based, long-term follow-up study of repeated self-harm in Taiwan

PubMed Central

2012-01-01

Background Previous follow-up studies of repeated self-harm show that the cumulative risk of repeated self-harm within one year is 5.7%–15%, with females at greatest risk. However, relatively few studies have focused on the Far East. The objective of this study was to calculate the cumulative risk of repeated self-harm over different lengths of follow-up time (3 months, 6 months, and 1–8 years), to determine factors influencing repeated self-harm and to explore the interaction between gender and self-harm methods. Methods We used self-harm patient who hospitalized due to first-time self-harm between 2000 and 2007 from 1,230 hospitals in Taiwan. Hospitalization for repeated self-harm among members of this cohort was tracked after 3 months, 6 months, and 1–8 years. Tracking continued until December 31, 2008. We analyzed the cumulative risk and risk factors of repeated self-harm by using negative binomial regression. Results Of the 39,875 individual study samples, 3,388 individuals (8.50%) were found to have repeatedly self-harmed. The cumulative risk of repeated self-harm within three months was 7.19% and within one year was 8%. Within 8 years, it was 8.70%. Females were more likely to repeatedly self-harm than males (RR = 1.21, 95% CI = 1.15–1.76). The main method of self-harm was solid or liquid substances (RR = 1.88, 95% CI = 1.23–2.04) or cutting or piercing (RR = 1.36, 95% CI = 1.02–1.82), and in patients with psychiatric disorders were more likely to self-harm (RR = 1.61, 95% CI = 1.48–1.75). Conclusions The key time for intervention for repeated self-harm is within three months. Appropriate prevention programs should be developed based on gender differences. PMID:22950416

Validation of a Hartmann-Moiré wavefront sensor with large dynamic range.

PubMed

Wei, Xin; Van Heugten, Tony; Thibos, Larry

2009-08-03

Our goal was to validate the accuracy, repeatability, sensitivity, and dynamic range of a Hartmann-Moiré (HM) wavefront sensor (PixelOptics, Inc.) designed for ophthalmic applications. Testing apparatus injected a 4 mm diameter monochromatic (532 nm) beam of light into the wavefront sensor for measurement. Controlled amounts of defocus and astigmatism were introduced into the beam with calibrated spherical (-20D to + 18D) and cylindrical (-8D to + 8D) lenses. Repeatability was assessed with three repeated measurements within a 2-minute period. Correlation coefficients between mean wavefront measurements (n = 3) and expected wavefront vergence for both sphere and cylinder lenses were >0.999. For spherical lenses, the sensor was accurate to within 0.1D over the range from -20D to + 18D. For cylindrical lenses, the sensor was accurate to within 0.1D over the range from -8D to + 8D. The primary limitation to demonstrating an even larger dynamic range was the increasingly critical requirements for optical alignment. Sensitivity to small changes of vergence was constant over the instrument's full dynamic range. Repeatability of measurements for fixed condition was within 0.01D. The Hartmann-Moiré wavefront sensor measures defocus and astigmatism accurately and repeatedly with good sensitivity over a large dynamic range required for ophthalmic applications.

Error-compensation model for simultaneous measurement of five degrees of freedom motion errors of a rotary axis

NASA Astrophysics Data System (ADS)

Bao, Chuanchen; Li, Jiakun; Feng, Qibo; Zhang, Bin

2018-07-01

This paper introduces an error-compensation model for our measurement method to measure five motion errors of a rotary axis based on fibre laser collimation. The error-compensation model is established in a matrix form using the homogeneous coordinate transformation theory. The influences of the installation errors, error crosstalk, and manufacturing errors are analysed. The model is verified by both ZEMAX simulation and measurement experiments. The repeatability values of the radial and axial motion errors are significantly suppressed by more than 50% after compensation. The repeatability experiments of five degrees of freedom motion errors and the comparison experiments of two degrees of freedom motion errors of an indexing table were performed by our measuring device and a standard instrument. The results show that the repeatability values of the angular positioning error ε z and tilt motion error around the Y axis ε y are 1.2″ and 4.4″, and the comparison deviations of the two motion errors are 4.0″ and 4.4″, respectively. The repeatability values of the radial and axial motion errors, δ y and δ z , are 1.3 and 0.6 µm, respectively. The repeatability value of the tilt motion error around the X axis ε x is 3.8″.

Repeatability of knee impulsive loading measurements with skin-mounted accelerometers and lower limb surface electromyographic recordings during gait in knee osteoarthritic and asymptomatic individuals

PubMed Central

Lyytinen, T.; Bragge, T.; Hakkarainen, M.; Liikavainio, T.; Karjalainen, P.A.; Arokoski, J.P.

2016-01-01

Objectives: To determine the repeatability of knee joint impulsive loading measurements with skin-mounted accelerometers (SMAs) and lower limb surface electromyography (EMG) recordings during gait. Methods: Triaxial SMA and EMG from 4 muscles during level and stair walking in nine healthy and nine knee osteoarthritis (OA) subjects were used. The initial peak acceleration (IPA), root mean square (RMS), maximal acceleration transient rate (ATRmax) and mean EMG activity (EMGact) were calculated. The coefficient of variation (CV) and the intraclass correlation coefficient (ICC) were calculated to measure repeatability. Results: The CV and ICC of RMS accelerations ranged from 4.9% to 10.9% and from 0.69 to 0.96 in both study groups during level walking. The CV and ICC of IPA and ATRmax varied from 7.7% to 14.2% and from 0.85 to 0.99 during level and stairs up walking in healthy subjects. The CV and ICC of EMGact ranged from 8.3% to 31.7% and from 0.16 to 0.97 in both study groups. Conclusions: RMS accelerations exhibited good repeatability during walking in healthy and knee OA subjects. The repeatability of EMG measurements was acceptable in healthy subjects depending on the measured muscles. PMID:26944825

Audiovisual material as educational innovation strategy to reduce anxiety response in students of human anatomy.

PubMed

Casado, María Isabel; Castaño, Gloria; Arráez-Aybar, Luis Alfonso

2012-08-01

This study presents the design, effect and utility of using audiovisual material containing real images of dissected human cadavers as an innovative educational strategy (IES) in the teaching of Human Anatomy. The goal is to familiarize students with the practice of dissection and to transmit the importance and necessity of this discipline, while modulating their anxiety. The study included 303 first-year Human Anatomy students, randomly assigned to two groups (Traditional and Educational Innovation). Their state of anxiety was measured using the State-Trait-Anxiety Inventory. Repeated measures ANOVA with between-subject factors was applied. The between-subject factor was Educational Innovation (EI). Two levels were established for this factor. The within-subject factor was Time, four levels being considered here. The results show that the effects of the Educational Innovation factor, Time factor and EI × Time interaction were statistically significant. These results provide an additional element of efficacy to the use of videos as an IES. That is, the use of video material as an introduction into an anxiety-provoking situation which resembles real-life viewing and interaction with human cadavers for the first time significantly diminishes the anticipatory reaction of dread against which novel students have not had the opportunity to develop any cognitive strategy of emotional control.

TU-F-CAMPUS-I-01: Head and Neck Squamous Cell Carcinoma: Short-Term Repeatability of Apparent Diffusion Coefficient and Intravoxel Incoherent Motion Parameters at 3.0T

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

Ding, Y; Fuller, C; Mohamed, A

2015-06-15

Purpose: Many published studies have recently demonstrated the potential value of intravoxel incoherent motion (IVIM) analysis for disease evaluation. However, few have questioned its measurement repeatability/reproducibility when applied. The purpose of this study was to determine the short-term measurement repeatability of apparent diffusion coefficient ADC, true diffusion coefficient D, pseudodiffusion coefficient D* and perfusion fraction f, in head and neck squamous cell carcinoma (HNSCC) primary tumors and metastatic nodes. Methods: Ten patients with known HNSCC were examined twice using echo-planar DW-MRI with 12 b values (0 to 800 s/mm2) 1hour to 24 hours apart before radiation treatment. All patients weremore » scanned with the customized radiation treatment immobilization devices to reduce motion artifacts and to improve image registration in repeat scans. Regions of interests were drawn in primary tumor and metastases node in each patient (Fig. 1). ADC and IVIM parameters D, D* and f were calculated by least squares data fitting. Short-term test–retest repeatability of ADC and IVIM parameters were assessed by measuring Bland–Altman limits of agreements (BA-LA). Results: Sixteen HNSCC lesions were assessed in 10 patients. Repeatability of perfusion-sensitive parameters, D* and f, in HNSCC lesions was poor (BA-LA: -144% to 88% and −57% to 96% for D* and f, respectively); a lesser extent was observed for the diffusion-sensitive parameters of ADC and D (BA-LA: −34% to 39% and −37% to 40%, for ADC and D, respectively) (Fig. 2). Conclusion: Poor repeatability of D*/f and good repeatability for ADC/D were observed in HNSCC primary tumors and metastatic nodes. Efforts should be made to improve the measurement repeatability of perfusion-sensitive IVIM parameters.« less

Socioeconomic and clinical characteristics associated with repeat suicide attempts among young people.

PubMed

Chen, Chuan-Yu; Yeh, Hsueh-Han; Huang, Nicole; Lin, Yun-Chen

2014-05-01

Repeat suicidal behaviors in young people are a critical public health concern. The study investigates individual socioeconomic and episode-dependent clinical factors predicting repeat suicide attempts among youth by gender. Using a retrospective cohort study, we identified a total of 4,094 male and 3,219 female youths who had the index suicide episode at the ages of 15-24 years from the 1996-2007 National Health Insurance Research Database in Taiwan. The recurrence of suicide attempt was assessed within 1 year after the index suicide. Information pertaining to suicide management and postsuicide treatment was obtained from healthcare records. Repeated event survival analyses were used to estimate episode-dependent risk of suicide attempt. The occurrence of repeat suicide attempts was more common in males, yet the phenomenon of risk aggravation appears more prominent in females. The estimate for peak hazard of the second repeat attempt was 2-fold higher than that of the first repeat event in males, and approximately 6-fold in females. Socioeconomic (e.g., labor market participation: adjusted Hazard Ratio [aHR] = 1.14, 95% CI = 1.01-1.28) and index suicide management characteristics (e.g., receiving treatment at clinic, aHR = 1.54, 95% CI = 1.19-1.99) were found to play important roles for repeat suicide attempts in males. For females, postsuicide treatment of mental disorders appears more influential. The relationships between socioeconomic and clinical factors with repeat suicide attempts in young people vary by gender. School/workplace-based post suicide attempt consultation and clinical management for youth may be planned and delivered on a gender-appropriate basis. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

The interaction of serum testosterone levels and androgen receptor CAG repeat polymorphism on the risk of erectile dysfunction in aging Taiwanese men.

PubMed

Liu, C C; Lee, Y C; Tsai, V F S; Cheng, K H; Wu, W J; Bao, B Y; Huang, C N; Yeh, H C; Tsai, C C; Wang, C J; Huang, S P

2015-09-01

Testosterone has been found to play important roles in men's sexual function. However, the effects of testosterone can be modulated by androgen receptor (AR) CAG repeat polymorphism. It could also contribute to the risk of erectile dysfunction (ED). The aim of this study is to evaluate the interaction of serum testosterone levels and AR CAG repeat polymorphism on the risk of ED in aging Taiwanese men. This cross-sectional data of Taiwanese men older than 40 years were collected from a free health screening held between August 2010 and August 2011 in Kaohsiung city, Taiwan. All participants completed a health questionnaires included five-item version of the International Index of Erectile Function (IIEF-5) and the International Prostate Symptoms Score, received a detailed physical examination and provided 20 cm3 whole blood samples for biochemical and genetic evaluation. The IIEF-5 was used to evaluate ED. Serum albumin, total testosterone (TT), and sex hormone-binding globulin levels were measured. Free testosterone level was calculated. AR gene CAG repeat polymorphism was determined by direct sequencing. Finally, 478 men with the mean age of 55.7 ± 4.8 years were included. When TT levels were above 330 ng/dL, the effect of testosterone level on erectile function seemed to reach a plateau and a significantly negative correlation between AR CAG repeat length and the score of IIEF-5 was found (r = -0.119, p = 0.034). After adjusting for other covariates, the longer AR CAG repeat length was still an independent risk factor for ED in subjects with TT above 330 ng/dL (p = 0.006), but not in TT of 330 ng/dL or below. In conclusion, both serum testosterone levels and AR CAG repeat polymorphism can influence erectile function concomitantly. In subjects with normal TT concentration, those with longer AR CAG repeat lengths have a higher risk of developing ED. © 2015 American Society of Andrology and European Academy of Andrology.

Persistent socioeconomic inequalities in cardiovascular risk factors in England over 1994-2008: A time-trend analysis of repeated cross-sectional data

PubMed Central

2012-01-01

Background Our aims were to determine the pace of change in cardiovascular risk factors by age, gender and socioeconomic groups from 1994 to 2008, and quantify the magnitude, direction and change in absolute and relative inequalities. Methods Time trend analysis was used to measure change in absolute and relative inequalities in risk factors by gender and age (16-54, ≥ 55 years), using repeated cross-sectional data from the Health Survey for England 1994-2008. Seven risk factors were examined: smoking, obesity, diabetes, high blood pressure, raised cholesterol, consumption of five or more daily portions of fruit and vegetables, and physical activity. Socioeconomic group was measured using the Index of Multiple Deprivation 2007. Results Between 1994 and 2008, the prevalence of smoking, high blood pressure and raised cholesterol decreased in most deprivation quintiles. However, obesity and diabetes increased. Increasing absolute inequalities were found in obesity in older men and women (p = 0.044 and p = 0.027 respectively), diabetes in young men and older women (p = 0.036 and p = 0.019 respectively), and physical activity in older women (p = 0.025). Relative inequality increased in high blood pressure in young women (p = 0.005). The prevalence of raised cholesterol showed widening absolute and relative inverse gradients from 1998 onwards in older men (p = 0.004 and p ≤ 0.001 respectively) and women (p ≤ 0.001 and p ≤ 0.001). Conclusions Favourable trends in smoking, blood pressure and cholesterol are consistent with falling coronary heart disease death rates. However, adverse trends in obesity and diabetes are likely to counteract some of these gains. Furthermore, little progress over the last 15 years has been made towards reducing inequalities. Implementation of known effective population based approaches in combination with interventions targeted at individuals/subgroups with poorer cardiovascular risk profiles are therefore recommended to reduce social inequalities. PMID:22333887

Impact of sleep difficulty on single and repeated injuries in adolescents.

PubMed

Chau, Kénora

2015-08-01

Injuries are frequent and may be caused by sleep difficulty in youth. This study assessed the impact of sleep difficulty on single and repeated school and out-of-school injuries and the confounding role of socioeconomic factors and school, behaviour and health-related difficulties among adolescents. The study population included 1559 middle-school adolescents from north-eastern France (mean age 13.5, SD 1.3) who completed at the end of school year a self-administered questionnaire to gather school and out-of-school injuries during the school year, and to assess sleep difficulty and previous injury risk factors which were socioeconomic factors (family structure, parents' education, father's occupation, and family income), school performance, obesity, alcohol/tobacco/cannabis/hard drugs use, health status, psychological health, and involvement-in-violence. For sleep difficulty and behaviour and health-related difficulties their first occurring over adolescent's life course was gathered. Multinomial logistic regression models were used retaining only sleep difficulty and other risk factors which had started before the school year (thus before the injuries studied). School and out-of-school injuries and sleep difficulty were frequent. The adolescents with sleep difficulty without medical treatment had a higher risk of single school and out-of-school injuries (gender-age-adjusted odds ratio gaOR 1.86 and 1.76, respectively) and a much higher risk of repeated school and out-of-school injuries (≥2 injuries; gaOR 2.43 and 3.73, respectively). The adolescents with persistent sleep difficulty despite a medical treatment also had a higher risk of single school and out-of-school injury (gaOR 2.31 and 1.78, respectively), and a much higher risk of repeated school and out-of-school injuries (gaOR 4.92 and 4.36, respectively). Socioeconomic factors had a moderate contribution (<27%) while school, behaviour and health-related difficulties had a high contribution (reaching 71%) to the association between sleep difficulty and single/repeated injuries. The role of these factors differed between single/repeated school/out-of-school injuries. Injury prevention should focus on screening and monitoring sleep difficulty and previous difficulties, especially among adolescents with socioeconomic difficulties, via physician-parent-school-adolescent collaborations. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Maristán stigma scale: a standardized international measure of the stigma of schizophrenia and other psychoses.

PubMed

Saldivia, Sandra; Runte-Geidel, Ariadne; Grandón, Pamela; Torres-González, Francisco; Xavier, Miguel; Antonioli, Claudio; Ballester, Dinarte A; Melipillán, Roberto; Galende, Emiliano; Vicente, Benjamín; Caldas, José Miguel; Killaspy, Helen; Gibbons, Rachel; King, Michael

2014-06-18

People with schizophrenia face prejudice and discrimination from a number of sources including professionals and families. The degree of stigma perceived and experienced varies across cultures and communities. We aimed to develop a cross-cultural measure of the stigma perceived by people with schizophrenia. Items for the scale were developed from qualitative group interviews with people with schizophrenia in six countries. The scale was then applied in face-to-face interviews with 164 participants, 103 of which were repeated after 30 days. Principal Axis Factoring and Promax rotation evaluated the structure of the scale; Horn's parallel combined with bootstrapping determined the number of factors; and intra-class correlation assessed test-retest reliability. The final scale has 31 items and four factors: informal social networks, socio-institutional, health professionals and self-stigma. Cronbach's alpha was 0.84 for the Factor 1; 0.81 for Factor 2; 0.74 for Factor 3, and 0.75 for Factor 4. Correlation matrix among factors revealed that most were in the moderate range [0.31-0.49], with the strongest occurring between perception of stigma in the informal network and self-stigma and there was also a weaker correlation between stigma from health professionals and self-stigma. Test-retest reliability was highest for informal networks [ICC 0.76 [0.67 -0.83

The Maristán stigma scale: a standardized international measure of the stigma of schizophrenia and other psychoses

PubMed Central

2014-01-01

Background People with schizophrenia face prejudice and discrimination from a number of sources including professionals and families. The degree of stigma perceived and experienced varies across cultures and communities. We aimed to develop a cross-cultural measure of the stigma perceived by people with schizophrenia. Method Items for the scale were developed from qualitative group interviews with people with schizophrenia in six countries. The scale was then applied in face-to-face interviews with 164 participants, 103 of which were repeated after 30 days. Principal Axis Factoring and Promax rotation evaluated the structure of the scale; Horn’s parallel combined with bootstrapping determined the number of factors; and intra-class correlation assessed test-retest reliability. Results The final scale has 31 items and four factors: informal social networks, socio-institutional, health professionals and self-stigma. Cronbach’s alpha was 0.84 for the Factor 1; 0.81 for Factor 2; 0.74 for Factor 3, and 0.75 for Factor 4. Correlation matrix among factors revealed that most were in the moderate range [0.31-0.49], with the strongest occurring between perception of stigma in the informal network and self-stigma and there was also a weaker correlation between stigma from health professionals and self-stigma. Test-retest reliability was highest for informal networks [ICC 0.76 [0.67 -0.83

Comparison of Eyemetrics and Orbscan automated method to determine horizontal corneal diameter

PubMed Central

Venkataraman, Arvind; Mardi, Sapna K; Pillai, Sarita

2010-01-01

Purpose: To compare horizontal corneal diameter measurements using the Orbscan Eyemetrics function and Orbscan corneal topographer. Materials and Methods: Seventy-three eyes of 37 patients were included in the study. In all cases, the automated white-to-white (WTW) measurements were obtained using Orbscan by two observers. Using the Eyemetrics function, the WTW was measured manually by the same observers from limbus to limbus using the digital caliper passing through the five point corneal reflections on the Orbscan real image. The data was analyzed using SPSS software for correlation, reliability and inter-rater repeatability. Results: The mean horizontal corneal diameter was 11.74 ± 0.32mm (SD) with the Orbscan and 11.92 ± 0.33mm (SD) with Eyemetrics Software-based measurement. A good positive correlation (Spearman r = 0.720, P = 0.026) was found between these two measurements. The coefficient of inter-rater repeatability was 0.89 for the Orbscan and 0.94 for the Eyemetrics software measurements on the anterior segment images. The Bland and Altman analysis showed large limits of agreement between Orbscan WTW and Eyemetrics WTW measurements. The intra-session repeatability scores for repeat measurements for the Orbscan WTW and Eyemetrics measurements were good. Conclusion: Eyemetrics can be used to measure WTW and the Eyemetrics measured WTW was longer than the WTW measured by Orbscan. PMID:20413925

High school students in a health career promotion program report fewer acts of aggression and violence.

PubMed

Oscós-Sánchez, Manuel Ángel; Lesser, Janna; Oscós-Flores, L Dolores

2013-01-01

This study examined the effects of two school-based programs on the perpetration of nonphysical aggression, physical violence, and intimate partner violence among high-risk secondary school students in an economically disadvantaged and predominantly Latino school district. The intervention program was El Joven Noble, and the control program was the Teen Medical Academy. The study used a repeated-measures quasi-experimental intervention/control design. The participants self-reported the previous 30 days' acts of nonphysical aggression, physical violence, and intimate partner violence at baseline and at 3 and 9 months after enrollment. Program- and grade-level effects at 3 and 9 months were examined using three-factor analyses of covariance models with one factor for repeated measures. The covariate in each of the models was the baseline measure of the dependent outcomes. No significant baseline differences were found between the participants in the intervention (n = 96) and control (n = 127) programs. At 9 months after enrollment in the study, high school students who participated in the Teen Medical Academy reported fewer acts of nonphysical aggression (p < .001) and physical violence (p = .002) than high school students who participated in El Joven Noble. Students who participated in the Teen Medical Academy also reported fewer acts of intimate partner violence (p = .02) than students who participated in El Joven Noble. High school students who participated in a health career promotion program reported fewer acts of aggression and violence as compared with high school students who participated in a culturally tailored character development program. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Intra-protocol repeatability and inter-protocol agreement for the analysis of scapulo-humeral coordination.

PubMed

Parel, I; Cutti, A G; Kraszewski, A; Verni, G; Hillstrom, H; Kontaxis, A

2014-03-01

Multi-center clinical trials incorporating shoulder kinematics are currently uncommon. The absence of repeatability and limits of agreement (LoA) studies between different centers employing different motion analysis protocols has led to a lack dataset compatibility. Therefore, the aim of this work was to determine the repeatability and LoA between two shoulder kinematic protocols. The first one uses a scapula tracker (ST), the International Society of Biomechanics anatomical frames and an optoelectronic measurement system, and the second uses a spine tracker, the INAIL Shoulder and Elbow Outpatient protocol (ISEO) and an inertial and magnetic measurement system. First within-protocol repeatability for each approach was assessed on a group of 23 healthy subjects and compared with the literature. Then, the between-protocol agreement was evaluated. The within-protocol repeatability was similar for the ST ([Formula: see text] = 2.35°, [Formula: see text] = 0.97°, SEM = 2.5°) and ISEO ([Formula: see text] = 2.24°, [Formula: see text] = 0.97°, SEM = 2.3°) protocols and comparable with data from published literature. The between-protocol agreement analysis showed comparable scapula medio-lateral rotation measurements for up to 120° of flexion-extension and up to 100° of scapula plane ab-adduction. Scapula protraction-retraction measurements were in agreement for a smaller range of humeral elevation. The results of this study suggest comparable repeatability for the ST and ISEO protocols and between-protocol agreement for two scapula rotations. Different thresholds for repeatability and LoA may be adapted to suit different clinical hypotheses.

Blockade of nicotine sensitization by methanol extracts of Glycyrrhizae radix mediated via antagonism of accumbal oxidative stress.

PubMed

Zhao, Zheng Lin; Kim, Sang Chan; Liu, Hong Feng; Wu, Yi Yan; Li, Li Bo; Wang, Yu Hua; Jiao, Yu; Fan, Yu; Lee, Chul Won; Lee, Bong Hyeo; Cho, Il Je; Yang, Chae Ha; Zhao, Rong Jie

2017-11-16

We previously reported that a methanol extract of Glycyrrhizae radix (MEGR) blocked methamphetamine-induced locomotor sensitization and conditioned place preference in rats. In the present study, the effects of MEGR on repeated nicotine-induced locomotor sensitization and enhanced extracellular dopamine (DA) release in the nucleus accumbens (Nacc) were evaluated. Male Sprague-Dawley rats received repeated administrations of nicotine (0.4 mg/kg, subcutaneous) or saline twice a day for 7 d and were challenged with nicotine 4 d after the last daily dosing. During the 4-d withdrawal period, the rats were treated once a day with MEGR (60 or 180 mg/kg/d). Extracellular DA levels were measured by in vivo microdialysis, the malondialdehyde levels and the activities of superoxide dismutase and catalase in the Nacc were biochemically evaluated, and the expression of antioxidant proteins was confirmed by Western blot assays. All data were assessed with analysis of variance tests followed by post-hoc comparison tests and p values <0.05 were considered statistically significant. The expression of repeated nicotine-induced locomotor sensitization was dose-dependently attenuated by MEGR, and 180 mg/kg/d MEGR significantly inhibited augmented accumbal DA release induced by a direct local challenge of nicotine. Moreover, 180 mg/kg/d MEGR reversed increases in malondialdehyde production, decreases in superoxide dismutase and catalase activities, and the reduced expression of nuclear factor erythroid 2-related factor 2 and heme oxygenase 1 in the nicotine-sensitized Nacc. These results suggest that MEGR inhibited nicotine-induced locomotion and dopaminergic sensitization via antioxidant action.

Large-scale assessment of polyglutamine repeat expansions in Parkinson disease

PubMed Central

Wang, Lisa; Aasly, Jan O.; Annesi, Grazia; Bardien, Soraya; Bozi, Maria; Brice, Alexis; Carr, Jonathan; Chung, Sun J.; Clarke, Carl; Crosiers, David; Deutschländer, Angela; Eckstein, Gertrud; Farrer, Matthew J.; Goldwurm, Stefano; Garraux, Gaetan; Hadjigeorgiou, Georgios M.; Hicks, Andrew A.; Hattori, Nobutaka; Klein, Christine; Jeon, Beom; Kim, Yun J.; Lesage, Suzanne; Lin, Juei-Jueng; Lynch, Timothy; Lichtner, Peter; Lang, Anthony E.; Mok, Vincent; Jasinska-Myga, Barbara; Mellick, George D.; Morrison, Karen E.; Opala, Grzegorz; Pihlstrøm, Lasse; Pramstaller, Peter P.; Park, Sung S.; Quattrone, Aldo; Rogaeva, Ekaterina; Ross, Owen A.; Stefanis, Leonidas; Stockton, Joanne D.; Silburn, Peter A.; Theuns, Jessie; Tan, Eng K.; Tomiyama, Hiroyuki; Toft, Mathias; Van Broeckhoven, Christine; Uitti, Ryan J.; Wirdefeldt, Karin; Wszolek, Zbigniew; Xiromerisiou, Georgia; Yueh, Kuo-Chu; Zhao, Yi; Gasser, Thomas; Maraganore, Demetrius M.; Krüger, Rejko

2015-01-01

Objectives: We aim to clarify the pathogenic role of intermediate size repeat expansions of SCA2, SCA3, SCA6, and SCA17 as risk factors for idiopathic Parkinson disease (PD). Methods: We invited researchers from the Genetic Epidemiology of Parkinson's Disease Consortium to participate in the study. There were 12,346 cases and 8,164 controls genotyped, for a total of 4 repeats within the SCA2, SCA3, SCA6, and SCA17 genes. Fixed- and random-effects models were used to estimate the summary risk estimates for the genes. We investigated between-study heterogeneity and heterogeneity between different ethnic populations. Results: We did not observe any definite pathogenic repeat expansions for SCA2, SCA3, SCA6, and SCA17 genes in patients with idiopathic PD from Caucasian and Asian populations. Furthermore, overall analysis did not reveal any significant association between intermediate repeats and PD. The effect estimates (odds ratio) ranged from 0.93 to 1.01 in the overall cohort for the SCA2, SCA3, SCA6, and SCA17 loci. Conclusions: Our study did not support a major role for definite pathogenic repeat expansions in SCA2, SCA3, SCA6, and SCA17 genes for idiopathic PD. Thus, results of this large study do not support diagnostic screening of SCA2, SCA3, SCA6, and SCA17 gene repeats in the common idiopathic form of PD. Likewise, this largest multicentered study performed to date excludes the role of intermediate repeats of these genes as a risk factor for PD. PMID:26354989

Dual implantation of a radio-telemeter and vascular access port allows repeated hemodynamic and pharmacological measures in conscious lean and obese rats.

PubMed

Bussey, C T; Leeuw, A E de; Cook, R F; Ashley, Z; Schofield, J; Lamberts, R R

2014-07-01

Expansion of physiological knowledge increasingly requires examination of processes in the normal, conscious state. The current study describes a novel approach combining surgical implantation of radio-telemeters with vascular access ports (VAPs) to allow repeated hemodynamic and pharmacological measures in conscious rats. Dual implantation was conducted on 16-week-old male lean and obese Zucker rats. Continued viability one month after surgery was observed in 67% of lean and 44% of obese animals, giving an overall 54% completion rate. Over the five-week measurement period, reliable and reproducible basal mean arterial pressure and heart rate measures were observed. VAP patency and receptor-independent vascular reactivity were confirmed by consistent hemodynamic responses to sodium nitroprusside (6.25 µg/kg). Acutely, minimal hemodynamic responses to repeated bolus administration of 0.2 mL saline indicated no significant effect of increased blood volume or administration stress, making repeated acute measures viable. Similarly, repeated administration of the β-adrenoceptor agonist dobutamine (30 µg/kg) at 10 min intervals resulted in reproducible hemodynamic changes in both lean and obese animals. Therefore, our study demonstrates that this new approach is viable for the acute and chronic assessment of hemodynamic and pharmacological responses in both lean and obese conscious rats. This technique reduces the demand for animal numbers and allows hemodynamic measures with minimal disruption to animals' welfare, while providing reliable and reproducible results over several weeks. In conclusion, dual implantation of a radio-telemeter and VAP introduces a valuable technique for undertaking comprehensive studies involving repeated pharmacological tests in conscious animals to address important physiological questions. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Effects of topical anaesthetics and repeated tonometry on intraocular pressure.

PubMed

Jóhannesson, Gauti; Hallberg, Per; Eklund, Anders; Behndig, Anders; Lindén, Christina

2014-03-01

To investigate the effects of repeated measurements of intraocular pressure (IOP) using Goldmann applanation tonometry (GAT) and applanation resonance tonometry (ART) to identify mechanisms contributing to the expected IOP reduction. A prospective, single-centre study with six healthy volunteers. Consecutive repeated series (six measurements/serie/method) were made alternately on both eyes for 1 hr with oxybuprocaine/fluorescein in the right eye and tetracaine in the left. The left eye was Pentacam(®) photographed before and repeatedly for 20 min after the IOP measurements. On a separate occasion, the same volunteers received the same amount of anaesthetic drops for 1 hr but without repeated IOP measurements. A significant IOP reduction occurred with both ART and GAT in the oxybuprocaine-treated eye, -4.4 mmHg and -3.8 mmHg, respectively and with ART in the tetracaine eye, -2.1 mmHg. There was a significant difference in IOP reduction between the oxybuprocaine and tetracaine eyes with ART. There was a significant drop in anterior chamber volume (ACV) immediately after the IOP measurements, -12.6 μl that returned to pretrial level after 2 min. After 1 hr of receiving anaesthetic eye drops (without IOP measurements), the IOP decreased significantly in the oxybuprocaine eye for both ART and GAT, -3.1 and -1.7 mmHg, respectively, but not in the tetracaine eye (p = 0.72). The IOP reduction cannot be explained solely by aqueous humor being pressed out of the anterior chamber. While significant IOP reduction occurred with both tetracaine and oxybuprocaine after repeated mechanical applanation, the IOP reduction was significantly greater with oxybuprocaine. © 2013 The Authors. Acta Ophthalmologica © 2013 Acta Ophthalmologica Scandinavica Foundation.

Three-dimensional assessment of the asymptomatic and post-stroke shoulder: intra-rater test-retest reliability and within-subject repeatability of the palpation and digitization approach.

PubMed

Pain, Liza A M; Baker, Ross; Sohail, Qazi Zain; Richardson, Denyse; Zabjek, Karl; Mogk, Jeremy P M; Agur, Anne M R

2018-03-23

Altered three-dimensional (3D) joint kinematics can contribute to shoulder pathology, including post-stroke shoulder pain. Reliable assessment methods enable comparative studies between asymptomatic shoulders of healthy subjects and painful shoulders of post-stroke subjects, and could inform treatment planning for post-stroke shoulder pain. The study purpose was to establish intra-rater test-retest reliability and within-subject repeatability of a palpation/digitization protocol, which assesses 3D clavicular/scapular/humeral rotations, in asymptomatic and painful post-stroke shoulders. Repeated measurements of 3D clavicular/scapular/humeral joint/segment rotations were obtained using palpation/digitization in 32 asymptomatic and six painful post-stroke shoulders during four reaching postures (rest/flexion/abduction/external rotation). Intra-class correlation coefficients (ICCs), standard error of the measurement and 95% confidence intervals were calculated. All ICC values indicated high to very high test-retest reliability (≥0.70), with lower reliability for scapular anterior/posterior tilt during external rotation in asymptomatic subjects, and scapular medial/lateral rotation, humeral horizontal abduction/adduction and axial rotation during abduction in post-stroke subjects. All standard error of measurement values demonstrated within-subject repeatability error ≤5° for all clavicular/scapular/humeral joint/segment rotations (asymptomatic ≤3.75°; post-stroke ≤5.0°), except for humeral axial rotation (asymptomatic ≤5°; post-stroke ≤15°). This noninvasive, clinically feasible palpation/digitization protocol was reliable and repeatable in asymptomatic shoulders, and in a smaller sample of painful post-stroke shoulders. Implications for Rehabilitation In the clinical setting, a reliable and repeatable noninvasive method for assessment of three-dimensional (3D) clavicular/scapular/humeral joint orientation and range of motion (ROM) is currently required. The established reliability and repeatability of this proposed palpation/digitization protocol will enable comparative 3D ROM studies between asymptomatic and post-stroke shoulders, which will further inform treatment planning. Intra-rater test-retest repeatability, which is measured by the standard error of the measure, indicates the range of error associated with a single test measure. Therefore, clinicians can use the standard error of the measure to determine the "true" differences between pre-treatment and post-treatment test scores.

System stability and calibrations for hand-held electromagnetic frequency domain instruments

NASA Astrophysics Data System (ADS)

Saksa, Pauli J.; Sorsa, Joona

2017-05-01

There are a few multiple-frequency domain electromagnetic induction (EMI) hand-held rigid boom systems available for shallow geophysical resistivity investigations. They basically measure secondary field real and imaginary components after the system calibrations. One multiple-frequency system, the EMP-400 Profiler from Geophysical Survey Systems Inc., was tested for system calibrations, stability and various effects present in normal measurements like height variation, tilting, signal stacking and time stability. Results indicated that in test conditions, repeatable high-accuracy imaginary component values can be recorded for near-surface frequency soundings. In test conditions, real components are also stable but vary strongly in normal surveying measurements. However, certain calibration issues related to the combination of user influence and measurement system height were recognised as an important factor in reducing for data errors and for further processing like static offset corrections.

Reliability of temporal summation and diffuse noxious inhibitory control

PubMed Central

Cathcart, Stuart; Winefield, Anthony H; Rolan, Paul; Lushington, Kurt

2009-01-01

BACKGROUND: The test-retest reliability of temporal summation (TS) and diffuse noxious inhibitory control (DNIC) has not been reported to date. Establishing such reliability would support the possibility of future experimental studies examining factors affecting TS and DNIC. Similarly, the use of manual algometry to induce TS, or an occlusion cuff to induce DNIC of TS to mechanical stimuli, has not been reported to date. Such devices may offer a simpler method than current techniques for inducing TS and DNIC, affording assessment at more anatomical locations and in more varied research settings. METHOD: The present study assessed the test-retest reliability of TS and DNIC using the above techniques. Sex differences on these measures were also investigated. RESULTS: Repeated measures ANOVA indicated successful induction of TS and DNIC, with no significant differences across test-retest occasions. Sex effects were not significant for any measure or interaction. Intraclass correlations indicated high test-retest reliability for all measures; however, there was large interindividual variation between test and retest measurements. CONCLUSION: The present results indicate acceptable within-session test-retest reliability of TS and DNIC. The results support the possibility of future experimental studies examining factors affecting TS and DNIC. PMID:20011713

Intraobserver Repeatability and Interobserver Reproducibility of Ellipsoid Zone Measurements in Retinitis Pigmentosa.

PubMed

Strampe, Margaret R; Huckenpahler, Alison L; Higgins, Brian P; Tarima, Sergey; Visotcky, Alexis; Stepien, Kimberly E; Kay, Christine N; Carroll, Joseph

2018-05-01

To examine repeatability and reproducibility of ellipsoid zone (EZ) width measurements in patients with retinitis pigmentosa (RP) using a longitudinal reflectivity profile (LRP) analysis. We examined Bioptigen optical coherence tomography (OCT) scans from 48 subjects with RP or Usher syndrome. Nominal scan lengths were 6, 7, or 10 mm, and the lateral scale of each scan was calculated using axial length measurements. LRPs were generated from OCT line scans, and the peak corresponding to EZ was manually identified using ImageJ. The locations at which the EZ peak disappeared were used to calculate EZ width. Each scan was analyzed twice by each of two observers, who were masked to their previous measurements and those of the other observer. On average, horizontal width (HW) was significantly greater than vertical width (VW), and there was high interocular symmetry for both HW and VW. We observed excellent intraobserver repeatability with intraclass correlation coefficients (ICCs) ranging from 0.996 to 0.998 for HW and VW measurements. Interobserver reproducibility was also excellent for both HW (ICC = 0.989; 95% confidence interval [CI] = 0.983-0.995) and VW (ICC = 0.991; 95% CI = 0.985-0.996), with no significant bias observed between observers. EZ width can be measured using LRPs with excellent repeatability and reproducibility. Our observation of greater HW than VW is consistent with previous observations in RP, though the reason for this anisotropy remains unclear. We describe repeatability and reproducibility of a method for measuring EZ width in patients with RP or Usher syndrome. This approach could facilitate measurement of retinal band thickness and/or intensity.

Kinematic repeatability of a multi-segment foot model for dance.

PubMed

Carter, Sarah L; Sato, Nahoko; Hopper, Luke S

2018-03-01

The purpose of this study was to determine the intra and inter-assessor repeatability of a modified Rizzoli Foot Model for analysing the foot kinematics of ballet dancers. Six university-level ballet dancers performed the movements; parallel stance, turnout plié, turnout stance, turnout rise and flex-point-flex. The three-dimensional (3D) position of individual reflective markers and marker triads was used to model the movement of the dancers' tibia, entire foot, hindfoot, midfoot, forefoot and hallux. Intra and inter-assessor reliability demonstrated excellent (ICC ≥ 0.75) repeatability for the first metatarsophalangeal joint in the sagittal plane. Intra-assessor reliability demonstrated excellent (ICC ≥ 0.75) repeatability during flex-point-flex across all inter-segmental angles except for the tibia-hindfoot and hindfoot-midfoot frontal planes. Inter-assessor repeatability ranged from poor to excellent (0.5 > ICC ≥ 0.75) for the 3D segment rotations. The most repeatable measure was the tibia-foot dorsiflexion/plantar flexion articulation whereas the least repeatable measure was the hindfoot-midfoot adduction/abduction articulation. The variation found in the inter-assessor results is likely due to inconsistencies in marker placement. This 3D dance specific multi-segment foot model provides insight into which kinematic measures can be reliably used to ascertain in vivo technical errors and/or biomechanical abnormalities in a dancer's foot motion.

Accommodating brightness and exposure levels in densitometry of stained polyacrylamide electrophoresis gels

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

Tan, Han Yen; Ng, Tuck Wah; Liew, Oi Wah

2010-03-20

Flatbed scanner densitometers can be operated under various illumination and recording exposure levels. In this work, we show that optical density measurement accuracy, sensitivity, and stability of stained polyacrylamide electrophoresis gel densitometry are crucially dependent on these two factors (brightness and exposure level), notwithstanding that the source is monochromatic, spatially uniform, and the measurements are made using an accurately calibrated step wedge in tandem. We further outline a method to accommodate the intensity deviations over a range of illumination and exposure levels in order to maintain sensitivity and repeatability in the computed optical densities. Comparisons were also made with resultsmore » from a commercial densitometer.« less

Improving power to detect changes in blood miRNA expression by accounting for sources of variability in experimental designs.

PubMed

Daniels, Sarah I; Sillé, Fenna C M; Goldbaum, Audrey; Yee, Brenda; Key, Ellen F; Zhang, Luoping; Smith, Martyn T; Thomas, Reuben

2014-12-01

Blood miRNAs are a new promising area of disease research, but variability in miRNA measurements may limit detection of true-positive findings. Here, we measured sources of miRNA variability and determine whether repeated measures can improve power to detect fold-change differences between comparison groups. Blood from healthy volunteers (N = 12) was collected at three time points. The miRNAs were extracted by a method predetermined to give the highest miRNA yield. Nine different miRNAs were quantified using different qPCR assays and analyzed using mixed models to identify sources of variability. A larger number of miRNAs from a publicly available blood miRNA microarray dataset with repeated measures were used for a bootstrapping procedure to investigate effects of repeated measures on power to detect fold changes in miRNA expression for a theoretical case-control study. Technical variability in qPCR replicates was identified as a significant source of variability (P < 0.05) for all nine miRNAs tested. Variability was larger in the TaqMan qPCR assays (SD = 0.15-0.61) versus the qScript qPCR assays (SD = 0.08-0.14). Inter- and intraindividual and extraction variability also contributed significantly for two miRNAs. The bootstrapping procedure demonstrated that repeated measures (20%-50% of N) increased detection of a 2-fold change for approximately 10% to 45% more miRNAs. Statistical power to detect small fold changes in blood miRNAs can be improved by accounting for sources of variability using repeated measures and choosing appropriate methods to minimize variability in miRNA quantification. This study demonstrates the importance of including repeated measures in experimental designs for blood miRNA research. See all the articles in this CEBP Focus section, "Biomarkers, Biospecimens, and New Technologies in Molecular Epidemiology." ©2014 American Association for Cancer Research.

Association between levels of C-reactive protein and leukocytes and cancer: Three repeated measurements in the Swedish AMORIS study

PubMed Central

Van Hemelrijck, Mieke; Holmberg, Lars; Garmo, Hans; Hammar, Niklas; Walldius, Göran; Binda, Elisa; Lambe, Mats; Jungner, Ingmar

2011-01-01

Objective To study levels of C-reactive protein (CRP) and leukocytes, as inflammatory markers, in the context of cancer risk. Methods From the Apolipoprotein MOrtality RISk (AMORIS) study, we selected 102,749 persons with one measurement and 9,273 persons with three repeated measurements of CRP and leukocytes. Multivariate Cox proportional hazards regression was applied to categories of CRP (<10, 10-15, 15-25, 25-50, >50 g/L) and quartiles of leukocytes. An Inflammation-based Predictive Score (IPS) indicated whether someone had CRP levels >10mg/L combined with leukocytes >10×109/L. Reverse causality was assessed by excluding those with <3, 5, or 7 years of follow-up. To analyze repeated measurements of CRP and leukocytes the repeated IPS (IPSr) was calculated by adding the IPS of each measurement. Results In the cohort with one measurement, there was a positive trend between CRP and cancer, with the lowest category being the reference: 0.99 (0.92-1.06), 1.28 (1.11-1.47), 1.27 (1.09-1.49), 1.22 (1.01-1.48) for the 2nd to 5th categories, respectively. This association disappeared when excluding those with follow-up <3, 5 or 7 years. The association between leukocytes and cancer was slightly stronger. In the cohort with repeated measurements the IPSr was strongly associated with cancer risk: 1.87 (1.33-2.63), 1.51 (0.56-4.06), 4.46 (1.43-13.87) for IPSr =1, 2, and 3, compared to IPSr =0. The association remained after excluding those with follow-up <1 year. Conclusions and impact Our large prospective cohort study adds evidence for a link between inflammatory markers and cancer risk by using repeated measurements and ascertaining reverse causality. PMID:21297038

Joint modelling of repeated measurement and time-to-event data: an introductory tutorial.

PubMed

Asar, Özgür; Ritchie, James; Kalra, Philip A; Diggle, Peter J

2015-02-01

The term 'joint modelling' is used in the statistical literature to refer to methods for simultaneously analysing longitudinal measurement outcomes, also called repeated measurement data, and time-to-event outcomes, also called survival data. A typical example from nephrology is a study in which the data from each participant consist of repeated estimated glomerular filtration rate (eGFR) measurements and time to initiation of renal replacement therapy (RRT). Joint models typically combine linear mixed effects models for repeated measurements and Cox models for censored survival outcomes. Our aim in this paper is to present an introductory tutorial on joint modelling methods, with a case study in nephrology. We describe the development of the joint modelling framework and compare the results with those obtained by the more widely used approaches of conducting separate analyses of the repeated measurements and survival times based on a linear mixed effects model and a Cox model, respectively. Our case study concerns a data set from the Chronic Renal Insufficiency Standards Implementation Study (CRISIS). We also provide details of our open-source software implementation to allow others to replicate and/or modify our analysis. The results for the conventional linear mixed effects model and the longitudinal component of the joint models were found to be similar. However, there were considerable differences between the results for the Cox model with time-varying covariate and the time-to-event component of the joint model. For example, the relationship between kidney function as measured by eGFR and the hazard for initiation of RRT was significantly underestimated by the Cox model that treats eGFR as a time-varying covariate, because the Cox model does not take measurement error in eGFR into account. Joint models should be preferred for simultaneous analyses of repeated measurement and survival data, especially when the former is measured with error and the association between the underlying error-free measurement process and the hazard for survival is of scientific interest. © The Author 2015; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Using the Fennema-Sherman Mathematics Attitude Scales with lower-primary teachers

NASA Astrophysics Data System (ADS)

Ren, Lixin; Green, Jennifer L.; Smith, Wendy M.

2016-06-01

The Fennema-Sherman Mathematics Attitude Scales (FSMAS) are among the most popular instruments used in studies of attitudes toward mathematics. However, the FSMAS has been mainly used among student populations and rarely used with teachers. In the present study, three scales from the FSMAS— Confidence, Effectance Motivation, and Anxiety—were revised and used with lower-primary (kindergarten to third grade) teachers. This study includes three parts: (1) a pilot study to ensure the modifications made to the FSMAS were appropriate to use with teachers, (2) confirmatory factor analyses to assess the factor structure of the revised FSMAS with 225 lower-primary teachers, and (3) measurement invariance analyses using data from a similar sample of 171 lower-primary teachers to examine whether the revised FSMAS measures each construct in the same way as in the previous sample. The final three-factor model, after removing three problematic items, achieves acceptable model fit, with each construct meeting all conditions for strict measurement invariance. Additionally, repeated measures analyses were performed on data collected from 39 in-service lower-primary teachers who participated in an elementary mathematics specialist program to examine the use of the revised FSMAS in program evaluation. Overall results suggest that researchers and program evaluators may use the revised FSMAS to reliably measure lower-primary teachers' mathematical attitudes, and it can be a valuable tool for evaluating the effectiveness of professional development programs.

Field gamma-ray spectrometer GS256: measurements stability

NASA Astrophysics Data System (ADS)

Mojzeš, Andrej

2009-01-01

The stability of in situ readings of the portable gamma-ray spectrometer GS256 during the field season of 2006 was studied. The instrument is an impulse detector of gamma rays based on NaI(Tl) 3" × 3" scintillation unit and 256-channel spectral analyzer which allows simultaneous assessment of up to 8 radioisotopes in rocks. It is commonly used in surface geophysical survey for the measurement of natural 40K, 238U and 232Th but also artificial 137Cs quantities. The statistical evaluation is given of both repeated measurements - in the laboratory and at several field control points in different survey areas. The variability of values shows both the instrument stability and also the relative influence of some meteorological factors, mainly rainfalls. The analysis shows an acceptable level of instrument measurements stability, the necessity to avoid measurement under unfavourable meteorological conditions and to keep detailed field book information about time, position and work conditions.

Global Repetition Influences Contextual Cueing

PubMed Central

Zang, Xuelian; Zinchenko, Artyom; Jia, Lina; Li, Hong

2018-01-01

Our visual system has a striking ability to improve visual search based on the learning of repeated ambient regularities, an effect named contextual cueing. Whereas most of the previous studies investigated contextual cueing effect with the same number of repeated and non-repeated search displays per block, the current study focused on whether a global repetition frequency formed by different presentation ratios between the repeated and non-repeated configurations influence contextual cueing effect. Specifically, the number of repeated and non-repeated displays presented in each block was manipulated: 12:12, 20:4, 4:20, and 4:4 in Experiments 1–4, respectively. The results revealed a significant contextual cueing effect when the global repetition frequency is high (≥1:1 ratio) in Experiments 1, 2, and 4, given that processing of repeated displays was expedited relative to non-repeated displays. Nevertheless, the contextual cueing effect reduced to a non-significant level when the repetition frequency reduced to 4:20 in Experiment 3. These results suggested that the presentation frequency of repeated relative to the non-repeated displays could influence the strength of contextual cueing. In other words, global repetition statistics could be a crucial factor to mediate contextual cueing effect. PMID:29636716

Global Repetition Influences Contextual Cueing.

PubMed

Zang, Xuelian; Zinchenko, Artyom; Jia, Lina; Assumpção, Leonardo; Li, Hong

2018-01-01

Our visual system has a striking ability to improve visual search based on the learning of repeated ambient regularities, an effect named contextual cueing. Whereas most of the previous studies investigated contextual cueing effect with the same number of repeated and non-repeated search displays per block, the current study focused on whether a global repetition frequency formed by different presentation ratios between the repeated and non-repeated configurations influence contextual cueing effect. Specifically, the number of repeated and non-repeated displays presented in each block was manipulated: 12:12, 20:4, 4:20, and 4:4 in Experiments 1-4, respectively. The results revealed a significant contextual cueing effect when the global repetition frequency is high (≥1:1 ratio) in Experiments 1, 2, and 4, given that processing of repeated displays was expedited relative to non-repeated displays. Nevertheless, the contextual cueing effect reduced to a non-significant level when the repetition frequency reduced to 4:20 in Experiment 3. These results suggested that the presentation frequency of repeated relative to the non-repeated displays could influence the strength of contextual cueing. In other words, global repetition statistics could be a crucial factor to mediate contextual cueing effect.

Modification of hippocampal markers of synaptic plasticity by memantine in animal models of acute and repeated restraint stress: implications for memory and behavior.

PubMed

Amin, Shaimaa Nasr; El-Aidi, Ahmed Amro; Ali, Mohamed Mostafa; Attia, Yasser Mahmoud; Rashed, Laila Ahmed

2015-06-01

Stress is any condition that impairs the balance of the organism physiologically or psychologically. The response to stress involves several neurohormonal consequences. Glutamate is the primary excitatory neurotransmitter in the central nervous system, and its release is increased by stress that predisposes to excitotoxicity in the brain. Memantine is an uncompetitive N-methyl D-aspartate glutamatergic receptors antagonist and has shown beneficial effect on cognitive function especially in Alzheimer's disease. The aim of the work was to investigate memantine effect on memory and behavior in animal models of acute and repeated restraint stress with the evaluation of serum markers of stress and the expression of hippocampal markers of synaptic plasticity. Forty-two male rats were divided into seven groups (six rats/group): control, acute restraint stress, acute restraint stress with Memantine, repeated restraint stress, repeated restraint stress with Memantine and Memantine groups (two subgroups as positive control). Spatial working memory and behavior were assessed by performance in Y-maze. We evaluated serum cortisol, tumor necrotic factor, interleukin-6 and hippocampal expression of brain-derived neurotrophic factor, synaptophysin and calcium-/calmodulin-dependent protein kinase II. Our results revealed that Memantine improved spatial working memory in repeated stress, decreased serum level of stress markers and modified the hippocampal synaptic plasticity markers in both patterns of stress exposure; in ARS, Memantine upregulated the expression of synaptophysin and brain-derived neurotrophic factor and downregulated the expression of calcium-/calmodulin-dependent protein kinase II, and in repeated restraint stress, it upregulated the expression of synaptophysin and downregulated calcium-/calmodulin-dependent protein kinase II expression.

Differences and similarities of risk factors for suicidal ideation and attempts among patients with depressive or bipolar disorders.

PubMed

Aaltonen, Kari; Näätänen, Petri; Heikkinen, Martti; Koivisto, Maaria; Baryshnikov, Ilya; Karpov, Boris; Oksanen, Jorma; Melartin, Tarja; Suominen, Kirsi; Joffe, Grigori; Paunio, Tiina; Isometsä, Erkki

2016-03-15

Substantial literature exists on risk factors for suicidal behaviour. However, their comparative strength, independence and specificity for either suicidal ideation or suicide attempt(s) remain unclear. The Helsinki University Psychiatric Consortium (HUPC) Study surveyed 287 psychiatric care patients with ICD-10-DCR depressive or bipolar disorders about lifetime suicidal behaviour, developmental history and attachment style, personality and psychological traits, current and lifetime symptom profiles, and life events. Psychiatric records were used to confirm diagnosis and complement information on suicide attempts. Multinomial regression models predicting lifetime suicidal ideation and single or repeated suicide attempts were generated. Overall, 21.6% patients had no lifetime suicidal behaviour, 33.8% had lifetime suicide ideation without attempts, and 17.1% had a single and 27.5% repeated suicide attempts. In univariate analyses, lifetime suicidal behaviour was associated with numerous factors. In multivariate models, suicidal ideation was independently predicted by younger age, severe depressive disorder, bipolar disorder type II/nos, hopelessness, and childhood physical abuse. Repeated suicide attempts were independently predicted by younger age, female sex, severe depressive disorder with or without psychotic symptoms, bipolar disorder type II/nos, alcohol use disorder, borderline personality disorder traits, and childhood physical abuse. Cross-sectional and retrospective study design, utilization of clinical diagnoses, and relatively low response rate. Risk factors for suicidal ideation and attempts may diverge both qualitatively and in terms of dose response. When effects of risk factors from multiple domains are concurrently examined, proximal clinical characteristics remain the most robust. All risk factors cluster into the group of repeated attempters. Copyright © 2015 Elsevier B.V. All rights reserved.

Fully automated laboratory and field-portable goniometer used for performing accurate and precise multiangular reflectance measurements

NASA Astrophysics Data System (ADS)

Harms, Justin D.; Bachmann, Charles M.; Ambeau, Brittany L.; Faulring, Jason W.; Ruiz Torres, Andres J.; Badura, Gregory; Myers, Emily

2017-10-01

Field-portable goniometers are created for a wide variety of applications. Many of these applications require specific types of instruments and measurement schemes and must operate in challenging environments. Therefore, designs are based on the requirements that are specific to the application. We present a field-portable goniometer that was designed for measuring the hemispherical-conical reflectance factor (HCRF) of various soils and low-growing vegetation in austere coastal and desert environments and biconical reflectance factors in laboratory settings. Unlike some goniometers, this system features a requirement for "target-plane tracking" to ensure that measurements can be collected on sloped surfaces, without compromising angular accuracy. The system also features a second upward-looking spectrometer to measure the spatially dependent incoming illumination, an integrated software package to provide full automation, an automated leveling system to ensure a standard frame of reference, a design that minimizes the obscuration due to self-shading to measure the opposition effect, and the ability to record a digital elevation model of the target region. This fully automated and highly mobile system obtains accurate and precise measurements of HCRF in a wide variety of terrain and in less time than most other systems while not sacrificing consistency or repeatability in laboratory environments.

Toward a simple, repeatable, non-destructive approach to measuring stable-isotope ratios of water within tree stems

NASA Astrophysics Data System (ADS)

Raulerson, S.; Volkmann, T.; Pangle, L. A.

2017-12-01

Traditional methodologies for measuring ratios of stable isotopes within the xylem water of trees involve destructive coring of the stem. A recent approach involves permanently installed probes within the stem, and an on-site assembly of pumps, switching valves, gas lines, and climate-controlled structure for field deployment of a laser spectrometer. The former method limits the possible temporal resolution of sampling, and sample size, while the latter may not be feasible for many research groups. We present results from initial laboratory efforts towards developing a non-destructive, temporally-resolved technique for measuring stable isotope ratios within the xylem flow of trees. Researchers have used direct liquid-vapor equilibration as a method to measure isotope ratios of the water in soil pores. Typically, this is done by placing soil samples in a fixed container, and allowing the liquid water within the soil to come into isotopic equilibrium with the headspace of the container. Water can also be removed via cryogenic distillation or azeotropic distillation, with the resulting liquid tested for isotope ratios. Alternatively, the isotope ratios of the water vapor can be directly measured using a laser-based water vapor isotope analyzer. Well-established fractionation factors and the isotope ratios in the vapor phase are then used to calculate the isotope ratios in the liquid phase. We propose a setup which would install a single, removable chamber onto a tree, where vapor samples could non-destructively and repeatedly be taken. These vapor samples will be injected into a laser-based isotope analyzer by a recirculating gas conveyance system. A major part of what is presented here is in the procedure of taking vapor samples at 100% relative humidity, appropriately diluting them with completely dry N2 calibration gas, and injecting them into the gas conveyance system without inducing fractionation in the process. This methodology will be helpful in making temporally resolved measurements of the stable isotopes in xylem water, using a setup that can be easily repeated by other research groups. The method is anticipated to find broad application in ecohydrological analyses, and in tracer studies aimed at quantifying age distributions of soil water extracted by plant roots.

Preliminary evaluation of a micro-based repeated measures testing system

NASA Technical Reports Server (NTRS)

Kennedy, Robert S.; Wilkes, Robert L.; Lane, Norman E.

1985-01-01

A need exists for an automated performance test system to study the effects of various treatments which are of interest to the aerospace medical community, i.e., the effects of drugs and environmental stress. The ethics and pragmatics of such assessment demand that repeated measures in small groups of subjects be the customary research paradigm. Test stability, reliability-efficiency and factor structure take on extreme significance; in a program of study by the U.S. Navy, 80 percent of 150 tests failed to meet minimum metric requirements. The best is being programmed on a portable microprocessor and administered along with tests in their original formats in order to examine their metric properties in the computerized mode. Twenty subjects have been tested over four replications on a 6.0 minute computerized battery (six tests) and which compared with five paper and pencil marker tests. All tests achieved stability within the four test sessions, reliability-efficiencies were high (r greater than .707 for three minutes testing), and the computerized tests were largely comparable to the paper and pencil version from which they were derived. This computerized performance test system is portable, inexpensive and rugged.

Group exposure therapy treatment for post-traumatic stress disorder in female veterans.

PubMed

Castillo, Diane T; C' de Baca, Janet; Qualls, Clifford; Bornovalova, Marina A

2012-12-01

The purpose of this study was to examine the application of a group exposure therapy model, the content of which consisted solely of repeated imaginal exposure during sessions, in a clinical sample of female veterans with post-traumatic stress disorder (PTSD). Establishing group delivery of exposure therapy will expand options, increase efficiency, and introduce group curative factors. Eighty-eight female veterans with PTSD completed a six-session exposure group, three participants per group, as a component of a larger treatment program. The PTSD symptom checklist (PCL) was used as the outcome measure and administered in each session. Pre/post-paired t-tests showed significant improvement in PTSD on the PCL, with 40% of completers showing at least a 10-point drop in the PCL scores. In addition, a repeated measures analysis of variance showed a significant main effect and a significant quadratic equation, with expected initial increases in the PCL followed by a decrease below baseline at session 6. The group exposure treatment protocol showed positive outcomes on PTSD symptoms in a real-world clinical sample of female veterans. The implications include an expansion of exposure treatment choices for veterans with PTSD and increased options for therapists.

Power analysis for multivariate and repeated measures designs: a flexible approach using the SPSS MANOVA procedure.

PubMed

D'Amico, E J; Neilands, T B; Zambarano, R

2001-11-01

Although power analysis is an important component in the planning and implementation of research designs, it is often ignored. Computer programs for performing power analysis are available, but most have limitations, particularly for complex multivariate designs. An SPSS procedure is presented that can be used for calculating power for univariate, multivariate, and repeated measures models with and without time-varying and time-constant covariates. Three examples provide a framework for calculating power via this method: an ANCOVA, a MANOVA, and a repeated measures ANOVA with two or more groups. The benefits and limitations of this procedure are discussed.

Clinical and Radiographic Characteristics as Predictive Factors of Swelling and Trismus after Mandibular Third Molar Surgery: A Longitudinal Approach

PubMed Central

Pérez-González, José Manuel; Esparza-Villalpando, Vicente; Martínez-Rider, Ricardo; Noyola-Frías, Miguel Ángel

2018-01-01

Introduction Factors that contribute to swelling and trismus are complex, and they are originated by surgical trauma. The aim of the present study was to determine whether clinical and radiographic factors could predict the level of swelling and trismus after lower third molar surgery, through longitudinal approach. Methodology A prospective longitudinal trial was carried out. Forty-five patients of both genders with clinical and radiographic diagnosis of asymptomatic mandibular impacted third molar and with no intake of analgesic or anti-inflammatory drugs 12 h prior to surgery were recruited and evaluated in a 72 h follow-up period. A mixed repeated measures model and backward and restricted maximal likelihood methods were used to analyze the data. Results Male gender, body mass index (BMI), the relation to the lingual and buccal walls, and age were determinants for predicting postoperative swelling and for exerting a significant influence (P < 0.05). Conclusions This study suggests the association of male gender, the relation to lingual and buccal walls, BMI, and age with measurement of swelling. PMID:29849848

A National Trial on Differences in Cerebral Perfusion Pressure Values by Measurement Location.

PubMed

McNett, Molly M; Bader, Mary Kay; Livesay, Sarah; Yeager, Susan; Moran, Cristina; Barnes, Arianna; Harrison, Kimberly R; Olson, DaiWai M

2018-04-01

Cerebral perfusion pressure (CPP) is a key parameter in management of brain injury with suspected impaired cerebral autoregulation. CPP is calculated by subtracting intracranial pressure (ICP) from mean arterial pressure (MAP). Despite consensus on importance of CPP monitoring, substantial variations exist on anatomical reference points used to measure arterial MAP when calculating CPP. This study aimed to identify differences in CPP values based on measurement location when using phlebostatic axis (PA) or tragus (Tg) as anatomical reference points. The secondary study aim was to determine impact of differences on patient outcomes at discharge. This was a prospective, repeated measures, multi-site national trial. Adult ICU patients with neurological injury necessitating ICP and CPP monitoring were consecutively enrolled from seven sites. Daily MAP/ICP/CPP values were gathered with the arterial transducer at the PA, followed by the Tg as anatomical reference points. A total of 136 subjects were enrolled, resulting in 324 paired observations. There were significant differences for CPP when comparing values obtained at PA and Tg reference points (p < 0.000). Differences remained significant in repeated measures model when controlling for clinical factors (mean CPP-PA = 80.77, mean CPP-Tg = 70.61, p < 0.000). When categorizing CPP as binary endpoint, 18.8% of values were identified as adequate with PA values, yet inadequate with CPP values measured at the Tg. Findings identify numerical differences for CPP based on anatomical reference location and highlight importance of a standard reference point for both clinical practice and future trials to limit practice variations and heterogeneity of findings.

Odor measurements according to EN 13725: A statistical analysis of variance components

NASA Astrophysics Data System (ADS)

Klarenbeek, Johannes V.; Ogink, Nico W. M.; van der Voet, Hilko

2014-04-01

In Europe, dynamic olfactometry, as described by the European standard EN 13725, has become the preferred method for evaluating odor emissions emanating from industrial and agricultural sources. Key elements of this standard are the quality criteria for trueness and precision (repeatability). Both are linked to standard values of n-butanol in nitrogen. It is assumed in this standard that whenever a laboratory complies with the overall sensory quality criteria for n-butanol, the quality level is transferable to other, environmental, odors. Although olfactometry is well established, little has been done to investigate inter laboratory variance (reproducibility). Therefore, the objective of this study was to estimate the reproducibility of odor laboratories complying with EN 13725 as well as to investigate the transferability of n-butanol quality criteria to other odorants. Based upon the statistical analysis of 412 odor measurements on 33 sources, distributed in 10 proficiency tests, it was established that laboratory, panel and panel session are components of variance that significantly differ between n-butanol and other odorants (α = 0.05). This finding does not support the transferability of the quality criteria, as determined on n-butanol, to other odorants and as such is a cause for reconsideration of the present single reference odorant as laid down in EN 13725. In case of non-butanol odorants, repeatability standard deviation (sr) and reproducibility standard deviation (sR) were calculated to be 0.108 and 0.282 respectively (log base-10). The latter implies that the difference between two consecutive single measurements, performed on the same testing material by two or more laboratories under reproducibility conditions, will not be larger than a factor 6.3 in 95% of cases. As far as n-butanol odorants are concerned, it was found that the present repeatability standard deviation (sr = 0.108) compares favorably to that of EN 13725 (sr = 0.172). It is therefore suggested that the repeatability limit (r), as laid down in EN 13725, can be reduced from r ≤ 0.477 to r ≤ 0.31.

Repeatability and reproducibility of measurements of the suburethral tape location obtained in pelvic floor ultrasound performed with a transvaginal probe

PubMed Central

Dresler, Maria Magdalena; Kociszewski, Jacek; Pędraszewski, Piotr; Trzeciak, Agnieszka; Surkont, Grzegorz

2017-01-01

Introduction Implants used to treat patients with urogynecological conditions are well visible in US examination. The position of the suburethral tape (sling) is determined in relation to the urethra or the pubic symphysis. Aim of the study The study was aimed at assessing the accuracy of measurements determining suburethral tape location obtained in pelvic US examination performed with a transvaginal probe. Material and methods The analysis covered the results of sonographic measurements obtained according to a standardized technique in women referred for urogynecological diagnostics. Data from a total of 68 patients were used to analyse the repeatability and reproducibility of results obtained on the same day. Results The intraclass correlation coefficient for the repeatability and reproducibility of the sonographic measurements of suburethral tape location obtained with a transvaginal probe ranged from 0.6665 to 0.9911. The analysis of the measurements confirmed their consistency to be excellent or good. Conclusions Excellent and good repeatability and reproducibility of the measurements of the suburethral tape location obtained in a pelvic ultrasound performed with a transvaginal probe confirm the test’s validity and usefulness for clinical and academic purposes. PMID:28856017

Test-retest reliability of the underlying latent factor structure of alcohol subjective response.

PubMed

Lutz, Joseph A; Childs, Emma

2017-04-01

Alcohol subjective experiences are multi-dimensional and demonstrate wide inter-individual variability. Recent efforts have sought to establish a clearer understanding of subjective alcohol responses by identifying core constructs derived from multiple measurement instruments. The aim of this study was to evaluate the temporal stability of this approach to conceptualizing alcohol subjective experiences across successive alcohol administrations in the same individuals. Healthy moderate alcohol drinkers (n = 104) completed six experimental sessions each, three with alcohol (0.8 g/kg), and three with a non-alcoholic control beverage. Participants reported subjective mood and drug effects using standardized questionnaires before and at repeated times after beverage consumption. We explored the underlying latent structure of subjective responses for all alcohol administrations using exploratory factor analysis and then tested measurement invariance over the three successive administrations using multi-group confirmatory factor analyses. Exploratory factor analyses on responses to alcohol across all administrations yielded four factors representing "Positive mood," "Sedation," "Stimulation/Euphoria," and "Drug effects and Urges." A confirmatory factor analysis on the separate administrations indicated acceptable configural and metric invariance and moderate scalar invariance. In this study, we demonstrate temporal stability of the underlying constructs of subjective alcohol responses derived from factor analysis. These findings strengthen the utility of this approach to conceptualizing subjective alcohol responses especially for use in prospective and longitudinal alcohol challenge studies relating subjective response to alcohol use disorder risk.

Does Wechsler Intelligence Scale administration and scoring proficiency improve during assessment training?

PubMed

Platt, Tyson L; Zachar, Peter; Ray, Glen E; Lobello, Steven G; Underhill, Andrea T

2007-04-01

Studies have found that Wechsler scale administration and scoring proficiency is not easily attained during graduate training. These findings may be related to methodological issues. Using a single-group repeated measures design, this study documents statistically significant, though modest, error reduction on the WAIS-III and WISC-III during a graduate course in assessment. The study design does not permit the isolation of training factors related to error reduction, or assessment of whether error reduction is a function of mere practice. However, the results do indicate that previous study findings of no or inconsistent improvement in scoring proficiency may have been the result of methodological factors. Implications for teaching individual intelligence testing and further research are discussed.

High-precision radius automatic measurement using laser differential confocal technology

NASA Astrophysics Data System (ADS)

Jiang, Hongwei; Zhao, Weiqian; Yang, Jiamiao; Guo, Yongkui; Xiao, Yang

2015-02-01

A high precision radius automatic measurement method using laser differential confocal technology is proposed. Based on the property of an axial intensity curve that the null point precisely corresponds to the focus of the objective and the bipolar property, the method uses the composite PID (proportional-integral-derivative) control to ensure the steady movement of the motor for process of quick-trigger scanning, and uses least-squares linear fitting to obtain the position of the cat-eye and confocal positions, then calculates the radius of curvature of lens. By setting the number of measure times, precision auto-repeat measurement of the radius of curvature is achieved. The experiment indicates that the method has the measurement accuracy of better than 2 ppm, and the measuring repeatability is better than 0.05 μm. In comparison with the existing manual-single measurement, this method has a high measurement precision, a strong environment anti-interference capability, a better measuring repeatability which is only tenth of former's.

Retinal nerve fiber layer measurements by scanning laser polarimetry with enhanced corneal compensation in healthy subjects.

PubMed

Rao, Harsha L; Venkatesh, Chirravuri R; Vidyasagar, Kelli; Yadav, Ravi K; Addepalli, Uday K; Jude, Aarthi; Senthil, Sirisha; Garudadri, Chandra S

2014-12-01

To evaluate the (i) effects of biological (age and axial length) and instrument-related [typical scan score (TSS) and corneal birefringence] parameters on the retinal nerve fiber layer (RNFL) measurements and (ii) repeatability of RNFL measurements with the enhanced corneal compensation (ECC) protocol of scanning laser polarimetry (SLP) in healthy subjects. In a cross-sectional study, 140 eyes of 73 healthy subjects underwent RNFL imaging with the ECC protocol of SLP. Linear mixed modeling methods were used to evaluate the effects of age, axial length, TSS, and corneal birefringence on RNFL measurements. One randomly selected eye of 48 subjects from the cohort underwent 3 serial scans during the same session to determine the repeatability. Age significantly influenced all RNFL measurements. RNFL measurements decreased by 1 µm for every decade increase in age. TSS affected the overall average RNFL measurement (β=-0.62, P=0.003), whereas residual anterior segment retardance affected the superior quadrant measurement (β=1.14, P=0.01). Axial length and corneal birefringence measurements did not influence RNFL measurements. Repeatability, as assessed by the coefficient of variation, ranged between 1.7% for the overall average RNFL measurement and 11.4% for th nerve fiber indicator. Age significantly affected all RNFL measurements with the ECC protocol of SLP, whereas TSS and residual anterior segment retardance affected the overall average and the superior average RNFL measurements, respectively. Axial length and corneal birefringence measurements did not influence any RNFL measurements. RNFL measurements had good intrasession repeatability. These results are important while evaluating the change in structural measurements over time in glaucoma patients.

Stress perception and (GT)n repeat polymorphism in haem oxygenase 1 promoter are both risk factors in development of eating disorders.

PubMed

Slachtová, L; Kaminská, D; Chvál, M; Králík, L; Martásek, P; Papežová, H

2013-01-01

Haem oxygenase 1 (HO-1) plays a pivotal role in metabolic stress protecting cells in dependence on reactive oxygen species. This study investigated a potential gene environment interaction between the (GT)n repeat HO1 polymorphism and the stress perception in patients with eating disorder and in controls. Stress perception and (GT)n polymorphism were measured in 127 patients with eating disorders and in 78 healthy controls using Stress and Coping Inventory and genotyping. Based on the inventory, overall, specific and weighted stress scores were defined. Clinical stress score was generated according to the patient's history and interviews. According to our hypothesis, 1) all stress scores describing subjective stress perception were significantly higher in patients compared to controls (P ≤ 0.001; P ≤ 0.002; P ≤ 0.001), 2) the L/L genotype of GT promoter repeats (L < 25 GT repeats, S < 25 GT repeats) in the patients was associated with higher overall (P ≤ 0.001), specific (P ≤ 0.010) and weighted stress score (P ≤ 0.005) compared to the L/S variant, and 3) Pearson's correlation of clinical versus objective stress scores showed not very tight relationship (0.198; 0.287; 0.224, respectively). We assume potential risk of the L allele of HO1 promoter polymorphism for the stress response and contribution of the subjective stress perception together with the L/L genotype to the development of eating disorder. Decreased HO1 expression in the presence of L/L genotype plus more intensive stress perception in the patients can lead to secondary stress, with increasing severity of the symptoms and aggravation of the disease.

[Effect of repeated fasting/refeeding on body weight control and energy balance regulation in rats].

PubMed

Wu, Bo; Du, Youai; Liu, Chongbin; Du, Zhou; Xiao, Min; Lu, Bo

2010-09-01

To investigate the changes of expression on leptin, a series of neuroendocrine factors and hormones associated with body weight control and energy balance regulation of rats, which were treated with repeated fasting/refeeding and followed by fed with high fat diet. Designing a repeated fasting/refeeding rats model (RFR) fed with basic stock diet on repeated cycles of 1 d fasting and 1 d refeeding for 6 weeks. The rats in RFR-LF/ HF group were switched to a high fat diet and fed the diet every day for another 6 weeks. The control rats were randomly divided into 3 groups, control group, high-fat diet (HF) group and common fat diet (CF) group. The rats in HF and CF group were killed by the end of the 12th week. The body weight, Lee's index, body fat content and serum lipid, GH, T4, leptin, insulin, and plasma ACTH levels were measured. The expression of NPY and POMC mRNA in hypothalamus were detected by reverse transcription chain reaction (RT-PCR). The Lee's index, body fat content, serum TC, TG, LDL, leptin and insulin levels of RFR-LF/HF group were lower significantly than those of HF group whereas higher significantly than those of CF group. The expression of NPY mRNA of RFR-LF/HF group were higher significantly than those of HF and CF groups, while the expression of POMC mRNA was lower significantly than that of HF and CF groups. The feeding pattern of repeated fasting/refeeding can decrease the degree of obesity induced by high fat diet, and also reduce the leptin and insulin resistance, but cause serious disturbance of the expression of neuroendocrine peptides in the central nervous system of rat.

Few millimeter precision for baselines in the California Permanent GPS Geodetic Array

NASA Technical Reports Server (NTRS)

Lindqwister, Ulf J.; Zumberge, James F.; Webb, Frank H.; Blewitt, Geoffrey

1991-01-01

Geodetic measurements with Rogue GPS receivers from sites in the California Permanent GPS geodetic Array (PGGA) have been analyzed using the GIPSY orbit-determination and baseline-estimation software. Based on an unbiased selection of 23 daily measurements spanning 8 months, the LF contributions to the long-term repeatabilities of baseline measurements are approximately 5, 3, and 8 mm for the east, north, and vertical components. Short-term contributions to the long-term repeatabilities were evaluated by examining data from the week of October 21, 1990, which showed the lowest short-term scatter. For this week, daily repeatabilities of 2-3 mm in the horizontal and 4 mm in the vertical have been achieved for the 172-km JPL-Pinyon baseline, consistent with carrier phase date noise of about 6 mm. High quality (less than about 5 mm) repeatabilities have been achieved for all components of the other baselines as well.

Cling film as a barrier against CJD in corneal contact A-scan ultrasonography.

PubMed

Rani, Asha; Dunne, Mark C M; Barnes, Derek A

2003-01-01

To determine the validity of covering a corneal contact transducer probe with cling film as protection against the transmission of Creutzfeldt-Jakob disease (CJD). The anterior chamber depth, lens thickness and vitreous chamber depth of the right eyes of 10 subjects was recorded, under cycloplegia, with and without cling film covering over the transducer probe of a Storz Omega Compu-scan Biometric Ruler. Measurements were repeated on two occasions. Cling film covering did not influence bias or repeatability. Although the 95% limits of agreement between measurements made with and without cling film covering tended to exceed the intrasessional repeatability, they did not exceed the intersessional repeatability of measurements taken without cling film. The results support the use of cling film as a disposable covering for corneal contact A-scan ultrasonography to avoid the risk of spreading CJD from one subject to another.

Automated Neuropsychological Assessment Metrics: Repeated Assessment with Two Military Samples

DTIC Science & Technology

2011-01-01

to ra- diation, high altitude, undersea conditions, and toxins ( 10,14,20 ). The putative advantages of ANAM4 (com- pared to other...repeated measures ANOVA. Separate analyses were performed for each of the ANAM subtests. Session was treated as a repeated variable. Huynh-Feldt epsilon

Fixation-free assessment of the Hirschberg ratio.

PubMed

Model, Dmitri; Eizenman, Moshe; Sturm, Veit

2010-08-01

To describe a novel methodology by which to measure the Hirschberg ratio (HR) in infants. The methodology does not require fixation on specific points, and measurements are made while infants look naturally at a display. The HR is calculated automatically from measurements of the direction of the optical axis, the position of the pupil center, and corneal reflexes in video images from an advanced two-camera eye-tracking system. The performance of the novel fixation-free procedure (FFP) was evaluated in 43 adults by measuring the average difference and the 95% limits of agreement with the standard fixation-based procedure (FBP). Repeatability of the HR measurements was evaluated by assessing the 95% limits of agreement between two independent measurements. Performance of the FFP was also evaluated in five infants. In adults, the average HR was 12.89 +/- 1.22 degrees/mm for FFP and 12.81 +/- 1.22 degrees/mm for FBP. FFP and FBP measurements were highly correlated (r = 0.95; P < 0.001). The 95% limits of agreement between FFP and FBP were +/-0.86 degrees/mm. The 95% limits of agreement of repeated measurements were +/-0.66 degrees/mm for FFP and +/-0.77 degrees/mm for FBP. In infants, the 95% limits of agreement of repeated measurements by FFP were +/-0.63 degrees/mm. In adults, the FFP provides accurate measurements of the HR that are in excellent agreement with measurements by FBP. In infants, measurements of HR by FFP show the same repeatability and consistency.

Awareness in contextual cueing of visual search as measured with concurrent access- and phenomenal-consciousness tasks.

PubMed

Schlagbauer, Bernhard; Müller, Hermann J; Zehetleitner, Michael; Geyer, Thomas

2012-10-25

In visual search, context information can serve as a cue to guide attention to the target location. When observers repeatedly encounter displays with identical target-distractor arrangements, reaction times (RTs) are faster for repeated relative to nonrepeated displays, the latter containing novel configurations. This effect has been termed "contextual cueing." The present study asked whether information about the target location in repeated displays is "explicit" (or "conscious") in nature. To examine this issue, observers performed a test session (after an initial training phase in which RTs to repeated and nonrepeated displays were measured) in which the search stimuli were presented briefly and terminated by visual masks; following this, observers had to make a target localization response (with accuracy as the dependent measure) and indicate their visual experience and confidence associated with the localization response. The data were examined at the level of individual displays, i.e., in terms of whether or not a repeated display actually produced contextual cueing. The results were that (a) contextual cueing was driven by only a very small number of about four actually learned configurations; (b) localization accuracy was increased for learned relative to nonrepeated displays; and (c) both consciousness measures were enhanced for learned compared to nonrepeated displays. It is concluded that contextual cueing is driven by only a few repeated displays and the ability to locate the target in these displays is associated with increased visual experience.

Repeatability of Ophtha Top topography and comparison with IOL-Master and LenstarLS900 in cataract patients

PubMed Central

Yu, Sha-Sha; Song, Hui; Tang, Xin

2017-01-01

AIM To determine the repeatability of Ophtha Top topography and assess the consistency with intraocular lens (IOL)-Master and LenstarLS900 (Lenstar) in measuring corneal parameters among cataract patients. METHODS Totally 125 eyes were enrolled. Corneas were successively measured with Ophtha Top, IOL-Master and Lenstar at least three times. The flattest meridian power (Kf), the steepest meridian power (Ks), mean power (Km), J0 and J45 were recorded. Intra-class correlation coefficients (ICCs), the coefficient of variance (COV), within subject standard deviation (Sw), and test-retest repeatability (2.77Sw) were adopted to determine the repeatability. The 95% limit of agreement (95%LOA) and Bland-Altman plots were used to assess comparability. RESULTS Repeatability of Ophtha Top topography for measuring corneal parameters showed the ICCs were all above 0.93, 2.77Sw was lower than 0.31, and the COV of the Kf and Ks was lower than 0.25. The keratometric readings with Ophtha Top topography were flatter than with the IOL-Master and Lenstar devices, while the Pearson correlation coefficients were over 0.97. The J0 and J45 with Ophtha Top topography were smaller compared with Lenstar and IOL-Master, while was comparable between Lenstar and IOL-Master. CONCLUSION Ophtha Top topography shows excellent repeatability for measuring corneal parameters. However, differences between the Ophtha TOP topography and Lenstar, IOL-Master both in cornea curvature and the astigmatism should be noted clinically. PMID:29181314

Repeatability of Ophtha Top topography and comparison with IOL-Master and LenstarLS900 in cataract patients.

PubMed

Yu, Sha-Sha; Song, Hui; Tang, Xin

2017-01-01

To determine the repeatability of Ophtha Top topography and assess the consistency with intraocular lens (IOL)-Master and LenstarLS900 (Lenstar) in measuring corneal parameters among cataract patients. Totally 125 eyes were enrolled. Corneas were successively measured with Ophtha Top, IOL-Master and Lenstar at least three times. The flattest meridian power (Kf), the steepest meridian power (Ks), mean power (Km), J0 and J45 were recorded. Intra-class correlation coefficients (ICCs), the coefficient of variance (COV), within subject standard deviation (Sw), and test-retest repeatability (2.77Sw) were adopted to determine the repeatability. The 95% limit of agreement (95%LOA) and Bland-Altman plots were used to assess comparability. Repeatability of Ophtha Top topography for measuring corneal parameters showed the ICCs were all above 0.93, 2.77Sw was lower than 0.31, and the COV of the Kf and Ks was lower than 0.25. The keratometric readings with Ophtha Top topography were flatter than with the IOL-Master and Lenstar devices, while the Pearson correlation coefficients were over 0.97. The J0 and J45 with Ophtha Top topography were smaller compared with Lenstar and IOL-Master, while was comparable between Lenstar and IOL-Master. Ophtha Top topography shows excellent repeatability for measuring corneal parameters. However, differences between the Ophtha TOP topography and Lenstar, IOL-Master both in cornea curvature and the astigmatism should be noted clinically.

L-statistics for Repeated Measurements Data With Application to Trimmed Means, Quantiles and Tolerance Intervals.

PubMed

Assaad, Houssein I; Choudhary, Pankaj K

2013-01-01

The L -statistics form an important class of estimators in nonparametric statistics. Its members include trimmed means and sample quantiles and functions thereof. This article is devoted to theory and applications of L -statistics for repeated measurements data, wherein the measurements on the same subject are dependent and the measurements from different subjects are independent. This article has three main goals: (a) Show that the L -statistics are asymptotically normal for repeated measurements data. (b) Present three statistical applications of this result, namely, location estimation using trimmed means, quantile estimation and construction of tolerance intervals. (c) Obtain a Bahadur representation for sample quantiles. These results are generalizations of similar results for independently and identically distributed data. The practical usefulness of these results is illustrated by analyzing a real data set involving measurement of systolic blood pressure. The properties of the proposed point and interval estimators are examined via simulation.

Risk factors of coercion among psychiatric inpatients: a nationwide register-based cohort study.

PubMed

Thomsen, Christoffer; Starkopf, Liis; Hastrup, Lene Halling; Andersen, Per Kragh; Nordentoft, Merete; Benros, Michael Eriksen

2017-08-01

Reducing the use of coercion among patients with mental disorders has long been a political priority. However, risk factors for coercive measures have primarily been investigated in smaller studies. To reduce the use of coercion, it is crucial to identify people at risk which we aim to do in this first large-scale study. A cohort study was conducted among all psychiatric inpatients in Denmark, following 112,233 individuals during 1999-2014. Data from Danish registers were analysed using logistic regression for repeated measures. 24,594 inpatients were exposed to a coercive measure (21.9%). Clinical characteristics were the foremost predictors of coercion and patients with organic mental disorder had the highest increased risk of being subjected to a coercive measure (OR = 5.56; 95% CI = 5.04, 6.14). The risk of coercion was the highest in the first admission and decreased with the number of admissions (all p < 0.001). The following socioeconomic variables were associated with an increased risk of coercion: male sex, unemployment, lower social class and immigrants from low and middle income countries (all p < 0.001). Early retirement and social relations, such as being married and having children, reduced the risk of being subjected to coercive measure (all p < 0.05). From our nationwide data, we identified a broad range of risk factors associated with coercive measures. Our findings can assist researchers in identifying patients at risk of coercion and thereby help targeting new coercion reduction programs.

Repeatability of Central and Peripheral Pulse Wave Velocity Measures: The Atherosclerosis Risk in Communities (ARIC) Study

PubMed Central

Tanaka, Hirofumi; Palta, Priya; Patel, Mehul D.; Camplain, Ricky; Couper, David; Cheng, Susan; Al Qunaibet, Ada; Poon, Anna K.; Heiss, Gerardo

2016-01-01

BACKGROUND Arterial stiffness measures are emerging tools for risk assessment and stratification for hypertension and cardiovascular disease (CVD). Carotid-femoral pulse wave velocity (cfPWV) is an established measure of central arterial stiffness. Other measures of PWV include femoral-ankle (faPWV), a measure of peripheral stiffness, and brachial-ankle PWV (baPWV), a composite measure of central and peripheral stiffness. Repeatability of central, peripheral, and composite PWV measures has not been adequately examined or compared. METHODS Participants (n = 79; mean age 75.7 years; USA) from a repeatability study nested within the Atherosclerosis Risk in Communities (ARIC) Study visit 5 (2011–2013) underwent 2 standardized visits, 4–8 weeks apart. Trained technicians obtained 2 PWV measurements at each visit using the VP-1000 Plus system. We calculated the intraclass correlation coefficient (ICC), SE of measurement, and minimal detectable change (MDC95; 95% confidence interval) and difference (MDD). RESULTS The ICCs and 95% confidence intervals (95% CIs) were 0.70 (0.59, 0.81) for cfPWV, 0.84 (0.78, 0.90) for baPWV, and 0.69 (0.59, 0.79) for faPWV. The MDC95 between repeat measures within an individual was 411.0cm/s for cfPWV, 370.6cm/s for baPWV, and 301.4cm/s for faPWV. The MDD for 2 independent samples of 100 per group was 139.3cm/s for cfPWV, 172.3cm/s for baPWV, and 100.4cm/s for faPWV. CONCLUSIONS Repeatability was acceptable for all PWV measures in a multicenter, population-based study of older adults and supports its use in epidemiologic studies. Quantifying PWV measurement variation is critical for applications to risk assessment and stratification and eventual translation to clinical practice. PMID:26232036

Comparative Robustness of Recent Methods for Analyzing Multivariate Repeated Measures Designs

ERIC Educational Resources Information Center

Seco, Guillermo Vallejo; Gras, Jaime Arnau; Garcia, Manuel Ato

2007-01-01

This study evaluated the robustness of two recent methods for analyzing multivariate repeated measures when the assumptions of covariance homogeneity and multivariate normality are violated. Specifically, the authors' work compares the performance of the modified Brown-Forsythe (MBF) procedure and the mixed-model procedure adjusted by the…

Testing Multiple Outcomes in Repeated Measures Designs

ERIC Educational Resources Information Center

Lix, Lisa M.; Sajobi, Tolulope

2010-01-01

This study investigates procedures for controlling the familywise error rate (FWR) when testing hypotheses about multiple, correlated outcome variables in repeated measures (RM) designs. A content analysis of RM research articles published in 4 psychology journals revealed that 3 quarters of studies tested hypotheses about 2 or more outcome…

Simulated Keratometry Repeatability in Subjects with & without Down Syndrome

PubMed Central

Ravikumar, Ayeswarya; Marsack, Jason D.; Benoit, Julia S.; Anderson, Heather A.

2016-01-01

Purpose To assess the repeatability of simulated keratometry measures obtained with Zeiss Atlas topography for subjects with and without Down syndrome (DS). Methods Corneal topography was attempted on 140 subjects with DS and 138 controls (aged 7 to 59 years). Subjects who had at least 3 measures in each eye were included in analysis (DS: n=140 eyes (70 subjects) and controls: n=264 eyes (132 subjects)). For each measurement the steep corneal power (K), corneal astigmatism, flat K orientation, power vector representation of astigmatism (J0, J45), and astigmatic dioptric difference were determined for each measurement (collectively termed keratometry values here). For flat K orientation comparisons, only eyes with >0.50 DC of astigmatism were included (DS: n=131 eyes (68 subjects) and control: n=217 eyes (119 subjects)). Repeatability was assessed using 1) group mean variability (average standard deviation (SD) across subjects), 2) coefficient of repeatability (COR) 3) coefficient of variation (COV), and 4) intraclass correlation coefficient (ICC). Results The keratometry values showed good repeatability as evidenced by low group mean variability for DS vs control eyes (≤0.26D vs ≤0.09D for all dioptric values; 4.51° vs 3.16° for flat K orientation); however, the group mean variability was significantly higher in DS eyes than control eyes for all parameters (p≤0.03). On average, group mean variability was 2.5× greater in the DS eyes compared to control eyes across the keratometry values. Other metrics of repeatability also indicated good repeatability for both populations for each keratometry value, although repeatability was always better in the control eyes. Conclusions DS eyes showed more variability (on average: 2.5×) compared to controls for all keratometry values. Although differences were statistically significant, on average 91% of DS eyes had variability ≤0.50D for steep K and astigmatism, and 75% of DS eyes had variability ≤5 degrees for flat K orientation. PMID:27741083

DNA motifs determining the accuracy of repeat duplication during CRISPR adaptation in Haloarcula hispanica

PubMed Central

Wang, Rui; Li, Ming; Gong, Luyao; Hu, Songnian; Xiang, Hua

2016-01-01

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) acquire new spacers to generate adaptive immunity in prokaryotes. During spacer integration, the leader-preceded repeat is always accurately duplicated, leading to speculations of a repeat-length ruler. Here in Haloarcula hispanica, we demonstrate that the accurate duplication of its 30-bp repeat requires two conserved mid-repeat motifs, AACCC and GTGGG. The AACCC motif was essential and needed to be ∼10 bp downstream from the leader-repeat junction site, where duplication consistently started. Interestingly, repeat duplication terminated sequence-independently and usually with a specific distance from the GTGGG motif, which seemingly served as an anchor site for a molecular ruler. Accordingly, altering the spacing between the two motifs led to an aberrant duplication size (29, 31, 32 or 33 bp). We propose the adaptation complex may recognize these mid-repeat elements to enable measuring the repeat DNA for spacer integration. PMID:27085805

Comparison of Walking, Muscle Strength, Balance, and Fear of Falling Between Repeated Fall Group, One-time Fall Group, and Nonfall Group of the Elderly Receiving Home Care Service.

PubMed

Jeon, MiYang; Gu, Mee Ock; Yim, JongEun

2017-12-01

The purpose of this study was to provide information to develop a program to prevent repeated falls by analyzing the difference in gait, muscle strength, balance, and fear of falling according to their fall experience. The study subjects were 110 elderly individuals aged over 60 years who agreed to their participation in this research. The study participants were categorized into a repeated fall group (n = 40), a one-time fall group (n = 15), and a nonfall group (n = 46) of the elderly. Measurements of gait, muscle strength, balance, and fear of falling were taken in each group. With regard to gait, there were significant differences among three groups in gait cycle (F = 3.50, p = .034), speed (F = 13.06, p < .001), and cadence (F = 5.59, p = .005). Regarding muscle strength in the upper and lower limbs, statistically significant differences were shown among three groups in muscle strength of upper (F = 16.98, p < .001) and lower (F = 10.55, p < .001) limbs. With regard to balance, the nonfall group had significantly greater results than the one-time fall group and repeated fall group in dynamic balance (F = 10.80, p < .001) and static balance (F = 8.20, p = .001). In the case of the fear of falling, the repeated fall group had significantly higher score than other two groups (F = 20.62, p < .001). This study suggests that intervention program should be tailored to fall risk factors to enhance gait and balance and lower body muscle strength and reduce the fear of falling to prevent repeated incidences of falls in this population. Copyright © 2017. Published by Elsevier B.V.

GT-repeat polymorphism in the heme oxygenase-1 gene promoter is associated with cardiovascular mortality risk in an arsenic-exposed population in northeastern Taiwan

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

Wu, Meei-Maan, E-mail: mmwu@tmu.edu.t; Graduate Institute of Oncology, College of Medicine, National Taiwan University, Taipei, Taiwan; Graduate Institute of Basic Medicine, College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan

2010-11-01

Inorganic arsenic has been associated with increased risk of atherosclerotic vascular disease and mortality in humans. A functional GT-repeat polymorphism in the heme oxygenase-1 (HO-1) gene promoter is inversely correlated with the development of coronary artery disease and restenosis after clinical angioplasty. The relationship of HO-1 genotype with arsenic-associated cardiovascular disease has not been studied. In this study, we evaluated the relationship between the HO-1 GT-repeat polymorphism and cardiovascular mortality in an arsenic-exposed population. A total of 504 study participants were followed up for a median of 10.7 years for occurrence of cardiovascular deaths (coronary heart disease, cerebrovascular disease, andmore » peripheral arterial disease). Cardiovascular risk factors and DNA samples for determination of HO-1 GT repeats were obtained at recruitment. GT repeats variants were grouped into the S (< 27 repeats) or L allele ({>=} 27 repeats). Relative mortality risk was estimated using Cox regression analysis, adjusted for competing risk of cancer and other causes. For the L/L, L/S, and S/S genotype groups, the crude mortalities for cardiovascular disease were 8.42, 3.10, and 2.85 cases/1000 person-years, respectively. After adjusting for conventional cardiovascular risk factors and competing risk of cancer and other causes, carriers with class S allele (L/S or S/S genotypes) had a significantly reduced risk of cardiovascular mortality compared to non-carriers (L/L genotype) [OR, 0.38; 95% CI, 0.16-0.90]. In contrast, no significant association was observed between HO-1 genotype and cancer mortality or mortality from other causes. Shorter (GT)n repeats in the HO-1 gene promoter may confer protective effects against cardiovascular mortality related to arsenic exposure.« less

High Regional Variation in Urethroplasty in the United States

PubMed Central

Figler, Bradley D.; Gore, John L.; Holt, Sarah K.; Voelzke, Bryan B.; Wessells, Hunter

2015-01-01

Purpose We identified clinical and regional factors associated with the use of urethroplasty vs repeat endoscopic management for urethral stricture disease. Materials and Methods We analyzed claims for patients 18 to 65 years old in the 2007 to 2011 MarketScan ® Commercial Claims and Encounters Database with a diagnosis of urethral stricture. The primary outcome was treatment with urethroplasty vs repeat endoscopic management, defined as more than 2 dilations or direct vision internal urethrotomies. The likelihood of urethroplasty vs repeat endoscopic management was determined for each major metropolitan area in the United States. Multivariate logistic regression was done to identify factors associated with urethroplasty. Results We identified 41,056 patients with urethral stricture, yielding a diagnosis rate of 296/100,000 men in MarketScan. Repeat endoscopic management and urethroplasty were performed in 2,700 and 1,444 patients, respectively. Compared to patients treated with repeat endoscopic management those with urethroplasty were younger (median age 44 vs 54 years) and more likely to have a Charlson comorbidity score of 0 (84% vs 77%), have traveled out of a metropolitan area for care (34% vs 17%) and have a reconstructive urologist in the treatment metropolitan area (76% and 62%, each p < 0.001). When controlling for age and Charlson comorbidity score, travel out of a metropolitan area (OR 2.7, 95% CI 2.2–3.3) and a reconstructive urologist in the treatment metropolitan area (OR 2.0, 95% CI 1.7–2.5) were associated with a greater likelihood of urethroplasty vs repeat endoscopic management. Conclusions Despite the well established benefits of urethroplasty compared to repeat endoscopic management a strong bias for repeat endoscopic management exists in many regions in the United States. PMID:25072180

Repeated exposure to immobilization or two different footshock intensities reveals differential adaptation of the hypothalamic-pituitary-adrenal axis.

PubMed

Rabasa, Cristina; Muñoz-Abellán, Cristina; Daviu, Núria; Nadal, Roser; Armario, Antonio

2011-05-03

Factors involved in adaptation to repeated stress are not well-characterized. For instance, acute footshock (FS) of high intensity appears to be less severe than immobilization (IMO) in light of the speed of post-stress recovery of the hypothalamic-pituitary-adrenal (HPA) axis and other physiological variables. However, repeated exposure to IMO consistently resulted in reduction of the HPA response to the same stressor (adaptation), whereas failure to adapt has been usually reported after FS. Thus, in the present work we directly compared the activation of HPA axis and other physiological changes in response to both acute and repeated exposure to IMO and two intensities of FS (medium and high) in adult male rats. Control rats were exposed to the FS boxes but they did not receive shocks. Daily repeated exposure to IMO resulted in significant adaptation of the overall ACTH and corticosterone responses to the stressor. Such a reduction was also observed with repeated exposure to FS boxes and FS-medium, whereas repeated exposure to FS-high only resulted in a small reduction of the corticosterone response during the post-stress period. This suggests that some properties of FS-high make adaptation to it difficult. Interestingly, overall changes in food intake and body weight gain throughout the week of exposure to the stressors reveal a greater impact of IMO than FS-high, indicating that factors other than the intensity of a stressor, at least when evaluated in function of the above physiological variables, can influence HPA adaptation. Since FS exposure is likely to cause more pain than IMO, activation of nociceptive signals above a certain level may negatively affect HPA adaptation to repeated stressors. Copyright © 2011 Elsevier Inc. All rights reserved.

hnRNP L binds to CA repeats in the 3'UTR of bcl-2 mRNA

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

Lee, Dong-Hyoung; Lim, Mi-Hyun; Youn, Dong-Ye

We previously reported that the CA-repeat sequence in the 3'-untranslated region (3'UTR) of bcl-2 mRNA is involved in the decay of bcl-2 mRNA. However, the trans-acting factor for the CA element in bcl-2 mRNA remains unidentified. The heterogeneous nuclear ribonucleoprotein L (hnRNP L), an intron splicing factor, has been reported to bind to CA repeats and CA clusters in the 3'UTR of several genes. We reported herein that the CA repeats of bcl-2 mRNA have the potential to form a distinct ribonuclear protein complex in cytoplasmic extracts of MCF-7 cells, as evidenced by RNA electrophoretic mobility shift assays (REMSA). Amore » super-shift assay using the hnRNP L antibody completely shifted the complex. Immunoprecipitation with the hnRNP L antibody and MCF-7 cells followed by RT-PCR revealed that hnRNP L interacts with endogenous bcl-2 mRNA in vivo. Furthermore, the suppression of hnRNP L in MCF-7 cells by the transfection of siRNA for hnRNP L resulted in a delay in the degradation of RNA transcripts including CA repeats of bcl-2 mRNA in vitro, suggesting that the interaction between hnRNPL and CA repeats of bcl-2 mRNA participates in destabilizing bcl-2 mRNA.« less

Clinical validity of macular ganglion cell complex by spectral domain-optical coherence tomography in advanced glaucoma.

PubMed

Sung, Mi-Sun; Kang, Byung-Wan; Kim, Hwang-Gyun; Heo, Hwan; Park, Sang-Woo

2014-08-01

To evaluate the repeatability and diagnostic power of macular ganglion cell complex (mGCC) thickness and peripapillary retinal nerve fiber layer (pRNFL) thickness using a spectral domain-optical coherence tomography in advanced glaucoma. Forty advanced glaucoma patients were enrolled. Patients were divided into 2 groups of 20 patients each, according to the MD between -20 and -10 dB, and <-20 dB. The thickness of mGCC and pRNFL were measured with spectral domain-optical coherence tomography in both the groups. The repeatability of each parameter was assessed in both the groups, and the diagnostic power of each parameter was compared with the normal controls. Comparison of diagnostic power between the pRNFL and mGCC parameters revealed that the area under the receiver operating characteristic curve was not significantly different in patients with advanced glaucoma. The repeatability of pRNFL parameters was similar, irrespective of the severity of glaucoma. However, the repeatability of mGCC parameters became lower as the severity increased in patients with advanced glaucoma. In advanced glaucoma, the measurement of mGCC thickness has similar diagnostic power as the measurement of pRNFL thickness. However, the measurement of mGCC thickness showed a lower repeatability as MD decreased.

Thirty-minute compared to standardised office blood pressure measurement in general practice

PubMed Central

Scherpbier-de Haan, Nynke; van der Wel, Mark; Schoenmakers, Gijs; Boudewijns, Steve; Peer, Petronella; van Weel, Chris; Thien, Theo; Bakx, Carel

2011-01-01

Background Although blood pressure measurement is one of the most frequently performed measurements in clinical practice, there are concerns about its reliability. Serial, automated oscillometric blood pressure measurement has the potential to reduce measurement bias and white-coat effect' Aim To study agreement of 30-minute office blood pressure measurement (OBPM) with standardised OBPM, and to compare repeatability Design and setting Method comparison study in two general practices in the Netherlands Method Thirty-minute and standardised OBPM was carried out with the same, validated device in 83 adult patients, and the procedure was repeated after 2 weeks. During 30-minute OBPM, blood pressure was measured automatically every 3 minutes, with the patient in a sitting position, alone in a quiet room. Agreement between 30-minute and standardised OBPM was assessed by Bland–Altman analysis. Repeatability of the blood pressure measurement methods after 2 weeks was expressed as the mean difference in combination with the standard deviation of difference (SDD) Results Mean 30-minute OBPM readings were 7.6/2.5 mmHg (95% confidence interval [CI] = 6.1 to 9.1/1.5 to 3.4 mmHg) lower than standardised OBPM readings. The mean difference and SDD between repeated 30-minute OBPMs (mean difference = 3/1 mmHg, 95% CI = 1 to 5/0 to 2 mmHg; SDD 9.5/5.3 mmHg) were lower than those of standardised OBPMs (mean difference = 6/2 mmHg, 95% CI = 4 to 8/1 to 4 mmHg; SDD 10.9/6.3 mmHg). Conclusion Thirty-minute OBPM resulted in lower readings than standardised OBPM and had a better repeatability. These results suggest that 30-minute OBPM better reflects the patient's true blood pressure than standardised OBPM does. PMID:22152748

A study of the Huntington's disease associated trinucleotide repeat in the Scottish population.

PubMed Central

Barron, L H; Warner, J P; Porteous, M; Holloway, S; Simpson, S; Davidson, R; Brock, D J

1993-01-01

Accurate measurements of a specific CAG repeat sequence in the Huntington's disease (HD) gene in 337 HD patients and 229 normal controls from the Scottish population showed a range from 35 to 62 repeats in affected subjects and eight to 33 in normal subjects. A link between early onset of symptoms and very high repeat number was seen. For HD patients with the most common affected allele sizes (39 to 42 repeats) absolute repeat size was a poor index for the age at onset of symptoms. There was variability in the transmitted repeat size for both sexes in the HD size range. We observed a significant increase of repeat size for paternal transmission of the disease and greater instability for paternally transmitted CAG repeats in the HD size range. Images PMID:8133495

Learning to actively cope with stress in female mice.

PubMed

Lyons, David M; Buckmaster, Christine L; Schatzberg, Alan F

2018-06-09

Repeated exposure to a same-sex resident stranger enhances subsequent indications of active coping that generalize across multiple contexts in intruder male mice. Here we investigate female mice for comparable learning to cope training effects. Stress coping research focused on females is important because stress related mood and anxiety disorders are more prevalent in women than men. Female mice were monitored for coping behavior in open-field, object-exploration, and tail-suspension tests conducted after repeated exposure to a same-sex resident stranger. During repeated exposure sessions of training staged in the resident's home cage, behavioral measures of aggression and risk assessment were collected and plasma measures of the stress hormone corticosterone were obtained from separate samples of mice. Repeated exposure to a same-sex resident stranger subsequently enhanced active coping behavior exemplified by diminished freezing and increased center entries in the open-field, shorter object-exploration latencies, and a tendency toward decreased immobility on tail-suspension tests. Open-field locomotion considered as an index of non-specific activity was not increased by repeated sessions of exposure and did not correlate significantly with any measure of active coping. During repeated sessions of exposure to a same-sex resident stranger, risk assessment behavior and consistent but limited aggression occurred and corticosterone responses increased over repeated sessions. Exposure to a same-sex resident stranger is mildly stressful and promotes learning to actively cope in mice assessed in three different contexts. Copyright © 2018. Published by Elsevier Ltd.

The upstream Variable Number Tandem Repeat polymorphism of the monoamine oxidase type A gene influences trigeminal pain-related evoked responses.

PubMed

Di Lorenzo, Cherubino; Daverio, Andrea; Pasqualetti, Patrizio; Coppola, Gianluca; Giannoudas, Ioannis; Barone, Ylenia; Grieco, Gaetano S; Niolu, Cinzia; Pascale, Esterina; Santorelli, Filippo M; Nicoletti, Ferdinando; Pierelli, Francesco; Siracusano, Alberto; Seri, Stefano; Di Lorenzo, Giorgio

2014-02-01

Monoamines have an important role in neural plasticity, a key factor in cortical pain processing that promotes changes in neuronal network connectivity. Monoamine oxidase type A (MAOA) is an enzyme that, due to its modulating role in monoaminergic activity, could play a role in cortical pain processing. The X-linked MAOA gene is characterized by an allelic variant of length, the MAOA upstream Variable Number Tandem Repeat (MAOA-uVNTR) region polymorphism. Two allelic variants of this gene are known, the high-activity MAOA (HAM) and low-activity MAOA (LAM). We investigated the role of MAOA-uVNTR in cortical pain processing in a group of healthy individuals measured by the trigeminal electric pain-related evoked potential (tPREP) elicited by repeated painful stimulation. A group of healthy volunteers was genotyped to detect MAOA-uVNTR polymorphism. Electrical tPREPs were recorded by stimulating the right supraorbital nerve with a concentric electrode. The N2 and P2 component amplitude and latency as well as the N2-P2 inter-peak amplitude were measured. The recording was divided into three blocks, each containing 10 consecutive stimuli and the N2-P2 amplitude was compared between blocks. Of the 67 volunteers, 37 were HAM and 30 were LAM. HAM subjects differed from LAM subjects in terms of amplitude of the grand-averaged and first-block N2-P2 responses (HAM>LAM). The N2-P2 amplitude decreased between the first and third block in HAM subjects but not LAM subjects. The MAOA-uVNTR polymorphism seemed to influence the brain response in a repeated tPREP paradigm and suggested a role of the MAOA as a modulator of neural plasticity related to cortical pain processing. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Consequences of Repeated Blood-Brain Barrier Disruption in Football Players

PubMed Central

Puvenna, Vikram; Janigro, Mattia; Ghosh, Chaitali; Zhong, Jianhui; Zhu, Tong; Blackman, Eric; Stewart, Desiree; Ellis, Jasmina; Butler, Robert; Janigro, Damir

2013-01-01

The acknowledgement of risks for traumatic brain injury in American football players has prompted studies for sideline concussion diagnosis and testing for neurological deficits. While concussions are recognized etiological factors for a spectrum of neurological sequelae, the consequences of sub-concussive events are unclear. We tested the hypothesis that blood-brain barrier disruption (BBBD) and the accompanying surge of the astrocytic protein S100B in blood may cause an immune response associated with production of auto-antibodies. We also wished to determine whether these events result in disrupted white matter on diffusion tensor imaging (DT) scans. Players from three college football teams were enrolled (total of 67 volunteers). None of the players experienced a concussion. Blood samples were collected before and after games (n = 57); the number of head hits in all players was monitored by movie review and post-game interviews. S100B serum levels and auto-antibodies against S100B were measured and correlated by direct and reverse immunoassays (n = 15 players; 5 games). A subset of players underwent DTI scans pre- and post-season and after a 6-month interval (n = 10). Cognitive and functional assessments were also performed. After a game, transient BBB damage measured by serum S100B was detected only in players experiencing the greatest number of sub-concussive head hits. Elevated levels of auto-antibodies against S100B were elevated only after repeated sub-concussive events characterized by BBBD. Serum levels of S100B auto-antibodies also predicted persistence of MRI-DTI abnormalities which in turn correlated with cognitive changes. Even in the absence of concussion, football players may experience repeated BBBD and serum surges of the potential auto-antigen S100B. The correlation of serum S100B, auto-antibodies and DTI changes support a link between repeated BBBD and future risk for cognitive changes. PMID:23483891

[Sexually transmitted infections in male prison inmates: risk of development of new diseases].

PubMed

Sánchez Recio, Raquel; Alonso Pérez de Ágreda, Juan Pablo; Santabárbara Serrano, Javier

2016-01-01

To measure incidence and main risk factors related to sexually transmitted infections (STIs) in Daroca Prison (Zaragoza, Spain). A retrospective cohort study (2005-2013) to measure the incidence of STI and a cross-sectional study to measure risk factors. Of the 203 inmates, 79 developed an STI, 37 had a previous STI, 55.2% lacked knowledge on STI prevention, and 28.9% showed behaviours unfavourable for STI prevention. The incidence rate was 6.5 STIs per 1,000 inmates-year. The most frequent STIs were hepatitis B (39.7%), Ureaplasma urealyticum (19.1%), herpes simplex (16.2%) and HIV (8.8%). The risk (hazard ratio, HR) of acquiring a new STI was significantly higher in inmates with a history of previous STI (HR=2.61; 95%CI: 1.01 to 6.69), and was at the limit of significance for non-preventive behaviour (HR=2.10; 95%CI: 0.98 to 4.53), but not in knowledge related to STIs (HR=1.33; 95%CI: 0.58 to 3.07). The most important risk factors in prison are behaviours related to STIs and previous history of STIs. Other factors are being a repeat offender, injecting drug use, or being in a methadone programme. Health personnel and peer education can facilitate prevention and control. Copyright © 2016 SESPAS. Published by Elsevier Espana. All rights reserved.

Image analysis of oronasal fistulas in cleft palate patients acquired with an intraoral camera.

PubMed

Murphy, Tania C; Willmot, Derrick R

2005-01-01

The aim of this study was to examine the clinical technique of using an intraoral camera to monitor the size of residual oronasal fistulas in cleft lip-cleft palate patients, to assess its repeatability on study casts and patients, and to compare its use with other methods. Seventeen plaster study casts of cleft palate patients with oronasal fistulas obtained from a 5-year series of 160 patients were used. For the clinical study, 13 patients presenting in a clinic prospectively over a 1-year period were imaged twice by the camera. The area of each fistula on each study cast was measured in the laboratory first using a previously described graph paper and caliper technique and second with the intraoral camera. Images were imported into a computer and subjected to image enhancement and area measurement. The camera was calibrated by imaging a standard periodontal probe within the fistula area. The measurements were repeated using a double-blind technique on randomly renumbered casts to assess the repeatability of measurement of the methods. The clinical images were randomly and blindly numbered and subjected to image enhancement and processing in the same way as for the study casts. Area measurements were computed. Statistical analysis of repeatability of measurement using a paired sample t test showed no significant difference between measurements, indicating a lack of systematic error. An intraclass correlation coefficient of 0.97 for the graph paper and 0.84 for the camera method showed acceptable random error between the repeated records for each of the two methods. The graph paper method remained slightly more repeatable. The mean fistula area of the study casts between each method was not statistically different when compared with a paired samples t test (p = 0.08). The methods were compared using the limits of agreement technique, which showed clinically acceptable repeatability. The clinical study of repeated measures showed no systematic differences when subjected to a t test (p = 0.109) and little random error with an intraclass correlation coefficient of 0.98. The fistula size seen in the clinical study ranged from 18.54 to 271.55 mm. Direct measurements subsequently taken on 13 patients in the clinic without study models showed a wide variation in the size of residual fistulas presenting in a multidisciplinary clinic. It was concluded that an intraoral camera method could be used in place of the previous graph paper method and could be developed for clinical and scientific purposes. This technique may offer advantages over the graph paper method, as it facilitates easy visualization of oronasal fistulas and objective fistulas size determination and permits easy storage of data in clinical records.

Repeated assessment of orthotopic glioma pO2 by multi-site EPR oximetry: A technique with the potential to guide therapeutic optimization by repeated measurements of oxygen

PubMed Central

Khan, Nadeem; Mupparaju, Sriram; Hou, Huagang; Williams, Benjamin B.; Swartz, Harold

2011-01-01

Tumor hypoxia plays a vital role in therapeutic resistance. Consequently, measurements of tumor pO2 could be used to optimize the outcome of oxygen-dependent therapies, such as, chemoradiation. However, the potential optimizations are restricted by the lack of methods to repeatedly and quantitatively assess tumor pO2 during therapies, particularly in gliomas. We describe the procedures for repeated measurements of orthotopic glioma pO2 by multi-site electron paramagnetic resonance (EPR) oximetry. This oximetry approach provides simultaneous measurements of pO2 at more than one site in the glioma and contralateral cerebral tissue. The pO2 of intracerebral 9L, C6, F98 and U251 tumors, as well as contralateral brain, were measured repeatedly for five consecutive days. The 9L glioma was well oxygenated with pO2 of 27 - 36 mm Hg, while C6, F98 and U251 glioma were hypoxic with pO2 of 7 - 12 mm Hg. The potential of multi-site EPR oximetry to assess temporal changes in tissue pO2 was investigated in rats breathing 100% O2. A significant increase in F98 tumor and contralateral brain pO2 was observed on day 1 and day 2, however, glioma oxygenation declined on subsequent days. In conclusion, EPR oximetry provides the capability to repeatedly assess temporal changes in orthotopic glioma pO2. This information could be used to test and optimize the methods being developed to modulate tumor hypoxia. Furthermore, EPR oximetry could be potentially used to enhance the outcome of chemoradiation by scheduling treatments at times of increase in glioma pO2. PMID:22079559

Repeated assessment of orthotopic glioma pO(2) by multi-site EPR oximetry: a technique with the potential to guide therapeutic optimization by repeated measurements of oxygen.

PubMed

Khan, Nadeem; Mupparaju, Sriram; Hou, Huagang; Williams, Benjamin B; Swartz, Harold

2012-02-15

Tumor hypoxia plays a vital role in therapeutic resistance. Consequently, measurements of tumor pO(2) could be used to optimize the outcome of oxygen-dependent therapies, such as, chemoradiation. However, the potential optimizations are restricted by the lack of methods to repeatedly and quantitatively assess tumor pO(2) during therapies, particularly in gliomas. We describe the procedures for repeated measurements of orthotopic glioma pO(2) by multi-site electron paramagnetic resonance (EPR) oximetry. This oximetry approach provides simultaneous measurements of pO(2) at more than one site in the glioma and contralateral cerebral tissue. The pO(2) of intracerebral 9L, C6, F98 and U251 tumors, as well as contralateral brain, were measured repeatedly for five consecutive days. The 9L glioma was well oxygenated with pO(2) of 27-36 mm Hg, while C6, F98 and U251 glioma were hypoxic with pO(2) of 7-12mm Hg. The potential of multi-site EPR oximetry to assess temporal changes in tissue pO(2) was investigated in rats breathing 100% O(2). A significant increase in F98 tumor and contralateral brain pO(2) was observed on day 1 and day 2, however, glioma oxygenation declined on subsequent days. In conclusion, EPR oximetry provides the capability to repeatedly assess temporal changes in orthotopic glioma pO(2). This information could be used to test and optimize the methods being developed to modulate tumor hypoxia. Furthermore, EPR oximetry could be potentially used to enhance the outcome of chemoradiation by scheduling treatments at times of increase in glioma pO(2). Copyright © 2011 Elsevier B.V. All rights reserved.

Measurements of clothing evaporative resistance using a sweating thermal manikin: an overview

PubMed Central

WANG, Faming

2017-01-01

Evaporative resistance has been widely used to describe the evaporative heat transfer property of clothing. It is also a critical variable in heat stress models for predicting human physiological responses in various environmental conditions. At present, sweating thermal manikins provide a fast and cost-effective way to determine clothing evaporative resistance. Unfortunately, the measurement repeatability and reproducibility of evaporative resistance are rather low due to the complicated moisture transfer processes through clothing. This review article presents a systematical overview on major influential factors affecting the measurement precision of clothing evaporative resistance measurements. It also illustrates the state-of-the-art knowledge on the development of test protocol to measure clothing evaporative resistance by means of a sweating manikin. Some feasible and robust test procedures for measurement of clothing evaporative resistance using a sweating manikin are described. Recommendations on how to improve the measurement accuracy of clothing evaporative resistance are addressed and expected future trends on development of advanced sweating thermal manikins are finally presented. PMID:28566566

Modification and Validation of the Treatment Self Regulation Questionnaire to Assess Parental Motivation for HPV Vaccination of Adolescents

PubMed Central

Denman, Deanna C.; Baldwin, Austin S.; Marks, Emily G.; Lee, Simon C.; Tiro, Jasmin A.

2016-01-01

Background According to Self-Determination Theory, the extent to which the motivation underlying behavior is self-determined or controlled influences its sustainability. This is particularly relevant for behaviors that must be repeated, such as completion of the human papillomavirus (HPV) vaccine series. To date, no measures of motivation for HPV vaccination have been developed. Methods As part of a larger study, parents (N=223) whose adolescents receive care at safety-net clinics completed a telephone questionnaire about HPV and the vaccine. We modified the Treatment Self-Regulation Questionnaire to assess parents’ motivation for HPV vaccination in both Spanish and English. We used confirmatory factor analysis to test a three-factor measurement model. Results The three-factor model fit the data well (RMSEA=.04, CFI=.98, TLI=.96), and the scales’ reliabilities were adequate (autonomous: α=.87; introjected: α=.72; external: α=.72). The factor loading strength for one item was stronger for Spanish- than English-speaking participants (p<.05); all others were equivalent. The intercorrelations among the scales ranged from −.17 to .32, suggesting discriminant factors. The scales displayed the expected pattern of correlations with other psychosocial determinants of behavior. Vaccination intentions showed a strong correlation with autonomous motivation (r= .52), but no correlation with external motivation (r=.02), suggesting autonomous motivation may be particularly important in vaccine decision-making. Conclusion Findings support the use of three subscales to measure motivation in HPV vaccination and suggest possible cultural differences in motivation. PMID:27595447

Repeatable electrical measurement instrumentation for use in the accelerated stress testing of thin film solar cells

NASA Technical Reports Server (NTRS)

Davis, C. W.; Lathrop, J. W.

1985-01-01

Attention is given to the construction, calibration, and performance of a repeatable measurement system for use in conjunction with the accelerated stress testing of a-Si:H cells. A filtered diode array is utilized to approximate the spectral response of any type of solar cell in discrete portions of the spectrum. It is noted that in order to achieve the necessary degree of overall repeatability, it is necessary to pay particular attention to methods of contacting and positioning the cells.

Quantitative Methods for Measuring Repair Rates and Innate-Immune Cell Responses in Wounded Mouse Skin.

PubMed

Li, Zhi; Gothard, Elizabeth; Coles, Mark C; Ambler, Carrie A

2018-01-01

In skin wounds, innate-immune cells clear up tissue debris and microbial contamination, and also secrete cytokines and other growth factors that impact repair process such as re-epithelialization and wound closure. After injury, there is a rapid influx and efflux of immune cells at wound sites, yet the function of each innate cell population in skin repair is still under investigation. Flow cytometry is a valuable research tool for detecting and quantifying immune cells; however, in mouse back skin, the difficulty in extracting immune cells from small area of skin due to tissue complexity has made cytometric analysis an underutilized tool. In this paper, we provide detailed methods on the digestion of lesion-specific skin without disrupting antigen expression followed by multiplex cell staining that allows for identification of seven innate-immune populations, including rare subsets such as group-3 innate lymphoid cells (ILC3s), by flow-cytometry analysis. Furthermore, when studying the functions of immune cells to tissue repair an important metric to monitor is size of the wound opening. Normal wounds close steadily albeit at non-linear rates, while slow or stalled wound closure can indicate an underlying problem with the repair process. Calliper measurements are difficult and time-consuming to obtain and can require repeated sedation of experimental animals. We provide advanced methods for measuring of wound openness; digital 3D image capture and semi-automated image processing that allows for unbiased, reliable measurements that can be taken repeatedly over time.

Quantitative Methods for Measuring Repair Rates and Innate-Immune Cell Responses in Wounded Mouse Skin

PubMed Central

Li, Zhi; Gothard, Elizabeth; Coles, Mark C.; Ambler, Carrie A.

2018-01-01

In skin wounds, innate-immune cells clear up tissue debris and microbial contamination, and also secrete cytokines and other growth factors that impact repair process such as re-epithelialization and wound closure. After injury, there is a rapid influx and efflux of immune cells at wound sites, yet the function of each innate cell population in skin repair is still under investigation. Flow cytometry is a valuable research tool for detecting and quantifying immune cells; however, in mouse back skin, the difficulty in extracting immune cells from small area of skin due to tissue complexity has made cytometric analysis an underutilized tool. In this paper, we provide detailed methods on the digestion of lesion-specific skin without disrupting antigen expression followed by multiplex cell staining that allows for identification of seven innate-immune populations, including rare subsets such as group-3 innate lymphoid cells (ILC3s), by flow-cytometry analysis. Furthermore, when studying the functions of immune cells to tissue repair an important metric to monitor is size of the wound opening. Normal wounds close steadily albeit at non-linear rates, while slow or stalled wound closure can indicate an underlying problem with the repair process. Calliper measurements are difficult and time-consuming to obtain and can require repeated sedation of experimental animals. We provide advanced methods for measuring of wound openness; digital 3D image capture and semi-automated image processing that allows for unbiased, reliable measurements that can be taken repeatedly over time. PMID:29535723

Estimate of the uncertainty in measurement for the determination of mercury in seafood by TDA AAS.

PubMed

Torres, Daiane Placido; Olivares, Igor R B; Queiroz, Helena Müller

2015-01-01

An approach for the estimate of the uncertainty in measurement considering the individual sources related to the different steps of the method under evaluation as well as the uncertainties estimated from the validation data for the determination of mercury in seafood by using thermal decomposition/amalgamation atomic absorption spectrometry (TDA AAS) is proposed. The considered method has been fully optimized and validated in an official laboratory of the Ministry of Agriculture, Livestock and Food Supply of Brazil, in order to comply with national and international food regulations and quality assurance. The referred method has been accredited under the ISO/IEC 17025 norm since 2010. The approach of the present work in order to reach the aim of estimating of the uncertainty in measurement was based on six sources of uncertainty for mercury determination in seafood by TDA AAS, following the validation process, which were: Linear least square regression, Repeatability, Intermediate precision, Correction factor of the analytical curve, Sample mass, and Standard reference solution. Those that most influenced the uncertainty in measurement were sample weight, repeatability, intermediate precision and calibration curve. The obtained result for the estimate of uncertainty in measurement in the present work reached a value of 13.39%, which complies with the European Regulation EC 836/2011. This figure represents a very realistic estimate of the routine conditions, since it fairly encompasses the dispersion obtained from the value attributed to the sample and the value measured by the laboratory analysts. From this outcome, it is possible to infer that the validation data (based on calibration curve, recovery and precision), together with the variation on sample mass, can offer a proper estimate of uncertainty in measurement.

Determinants of the reliability of ultrasound tomography sound speed estimates as a surrogate for volumetric breast density

PubMed Central

Khodr, Zeina G.; Sak, Mark A.; Pfeiffer, Ruth M.; Duric, Nebojsa; Littrup, Peter; Bey-Knight, Lisa; Ali, Haythem; Vallieres, Patricia; Sherman, Mark E.; Gierach, Gretchen L.

2015-01-01

Purpose: High breast density, as measured by mammography, is associated with increased breast cancer risk, but standard methods of assessment have limitations including 2D representation of breast tissue, distortion due to breast compression, and use of ionizing radiation. Ultrasound tomography (UST) is a novel imaging method that averts these limitations and uses sound speed measures rather than x-ray imaging to estimate breast density. The authors evaluated the reproducibility of measures of speed of sound and changes in this parameter using UST. Methods: One experienced and five newly trained raters measured sound speed in serial UST scans for 22 women (two scans per person) to assess inter-rater reliability. Intrarater reliability was assessed for four raters. A random effects model was used to calculate the percent variation in sound speed and change in sound speed attributable to subject, scan, rater, and repeat reads. The authors estimated the intraclass correlation coefficients (ICCs) for these measures based on data from the authors’ experienced rater. Results: Median (range) time between baseline and follow-up UST scans was five (1–13) months. Contributions of factors to sound speed variance were differences between subjects (86.0%), baseline versus follow-up scans (7.5%), inter-rater evaluations (1.1%), and intrarater reproducibility (∼0%). When evaluating change in sound speed between scans, 2.7% and ∼0% of variation were attributed to inter- and intrarater variation, respectively. For the experienced rater’s repeat reads, agreement for sound speed was excellent (ICC = 93.4%) and for change in sound speed substantial (ICC = 70.4%), indicating very good reproducibility of these measures. Conclusions: UST provided highly reproducible sound speed measurements, which reflect breast density, suggesting that UST has utility in sensitively assessing change in density. PMID:26429241

Determinants of the reliability of ultrasound tomography sound speed estimates as a surrogate for volumetric breast density

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

Khodr, Zeina G.; Pfeiffer, Ruth M.; Gierach, Gretchen L., E-mail: GierachG@mail.nih.gov

Purpose: High breast density, as measured by mammography, is associated with increased breast cancer risk, but standard methods of assessment have limitations including 2D representation of breast tissue, distortion due to breast compression, and use of ionizing radiation. Ultrasound tomography (UST) is a novel imaging method that averts these limitations and uses sound speed measures rather than x-ray imaging to estimate breast density. The authors evaluated the reproducibility of measures of speed of sound and changes in this parameter using UST. Methods: One experienced and five newly trained raters measured sound speed in serial UST scans for 22 women (twomore » scans per person) to assess inter-rater reliability. Intrarater reliability was assessed for four raters. A random effects model was used to calculate the percent variation in sound speed and change in sound speed attributable to subject, scan, rater, and repeat reads. The authors estimated the intraclass correlation coefficients (ICCs) for these measures based on data from the authors’ experienced rater. Results: Median (range) time between baseline and follow-up UST scans was five (1–13) months. Contributions of factors to sound speed variance were differences between subjects (86.0%), baseline versus follow-up scans (7.5%), inter-rater evaluations (1.1%), and intrarater reproducibility (∼0%). When evaluating change in sound speed between scans, 2.7% and ∼0% of variation were attributed to inter- and intrarater variation, respectively. For the experienced rater’s repeat reads, agreement for sound speed was excellent (ICC = 93.4%) and for change in sound speed substantial (ICC = 70.4%), indicating very good reproducibility of these measures. Conclusions: UST provided highly reproducible sound speed measurements, which reflect breast density, suggesting that UST has utility in sensitively assessing change in density.« less

Child Maltreatment and Repeat Presentations to the Emergency Department for Suicide-Related Behaviors

ERIC Educational Resources Information Center

Rhodes, Anne E.; Boyle, Michael H.; Bethell, Jennifer; Wekerle, Christine; Tonmyr, Lil; Goodman, Deborah; Leslie, Bruce; Lam, Kelvin; Manion, Ian

2013-01-01

Objectives: To identify factors associated with repeat emergency department (ED) presentations for suicide-related behaviors (SRB)--hereafter referred to as repetition--among children/youth to aid secondary prevention initiatives. To compare rates of repetition in children/youth with substantiated maltreatment requiring removal from their parental…

On Partial Fraction Decompositions by Repeated Polynomial Divisions

ERIC Educational Resources Information Center

Man, Yiu-Kwong

2017-01-01

We present a method for finding partial fraction decompositions of rational functions with linear or quadratic factors in the denominators by means of repeated polynomial divisions. This method does not involve differentiation or solving linear equations for obtaining the unknown partial fraction coefficients, which is very suitable for either…

The development and validation of the King's Brief Interstitial Lung Disease (K-BILD) health status questionnaire.

PubMed

Patel, Amit S; Siegert, Richard J; Brignall, Katherine; Gordon, Patrick; Steer, Sophia; Desai, Sujal R; Maher, Toby M; Renzoni, Elisabetta A; Wells, Athol U; Higginson, Irene J; Birring, Surinder S

2012-09-01

Health status is impaired in patients with interstitial lung disease (ILD). There is a paucity of tools that assess health status in ILD. The objective of this study was to develop and validate the King's Brief Interstitial Lung Disease questionnaire (K-BILD), a new health status measure for patients with ILD. Patients with ILD were recruited from outpatient clinics. The development of the questionnaire consisted of three phases: item generation; item reduction, allocation to domains by factor analysis, Rasch analysis to create unidimensional scales and validation; and repeatability testing. 173 patients with ILD (49 with idiopathic pulmonary fibrosis) completed a preliminary 71-item questionnaire. 56 items were removed due to redundancy, low factor loadings or poor fit to the Rasch model. The final version of the K-BILD questionnaire consisted of 15 items and three domains (breathlessness and activities, chest symptoms and psychological). Internal consistency assessed with Cronbach's α coefficient was 0.94 for the K-BILD total score. Concurrent validity of the K-BILD questionnaire was high compared with St George's Respiratory Questionnaire (r=0.90) and moderate with lung function (vital capacity, r=0.50). The K-BILD questionnaire was repeatable over 2 weeks (n=44), with intraclass correlation coefficients for domains and total score 0.86-0.94. The K-BILD construct validity for patients with idiopathic pulmonary fibrosis was similar to that of other ILDs. The K-BILD questionnaire is a brief, valid, self-completed health status measure for ILD. It could be used in the clinic to assess ILD from the patients' perspective.

The natural history of spinocerebellar ataxia type 1, 2, 3, and 6

PubMed Central

Jacobi, H.; Bauer, P.; Giunti, P.; Labrum, R.; Sweeney, M.G.; Charles, P.; Dürr, A.; Marelli, C.; Globas, C.; Linnemann, C.; Schöls, L.; Rakowicz, M.; Rola, R.; Zdzienicka, E.; Schmitz-Hübsch, T.; Fancellu, R.; Mariotti, C.; Tomasello, C.; Baliko, L.; Melegh, B.; Filla, A.; Rinaldi, C.; van de Warrenburg, B.P.; Verstappen, C.C.P.; Szymanski, S.; Berciano, J.; Infante, J.; Timmann, D.; Boesch, S.; Hering, S.; Depondt, C.; Pandolfo, M.; Kang, J.-S.; Ratzka, S.; Schulz, J.; Tezenas du Montcel, S.

2011-01-01

Objective: To obtain quantitative data on the progression of the most common spinocerebellar ataxias (SCAs) and identify factors that influence their progression, we initiated the EUROSCA natural history study, a multicentric longitudinal cohort study of 526 patients with SCA1, SCA2, SCA3, or SCA6. We report the results of the 1- and 2-year follow-up visits. Methods: As the primary outcome measure we used the Scale for the Assessment and Rating of Ataxia (SARA, 0–40), and as a secondary measure the Inventory of Non-Ataxia Symptoms (INAS, 0–16) count. Results: The annual increase of the SARA score was greatest in SCA1 (2.18 ± 0.17, mean ± SE) followed by SCA3 (1.61 ± 0.12) and SCA2 (1.40 ± 0.11). SARA progression in SCA6 was slowest and nonlinear (first year: 0.35 ± 0.34, second year: 1.44 ± 0.34). Analysis of the INAS count yielded similar results. Larger expanded repeats and earlier age at onset were associated with faster SARA progression in SCA1 and SCA2. In SCA1, repeat length of the expanded allele had a similar effect on INAS progression. In SCA3, SARA progression was influenced by the disease duration at inclusion, and INAS progression was faster in females. Conclusions: Our study gives a comprehensive quantitative account of disease progression in SCA1, SCA2, SCA3, and SCA6 and identifies factors that specifically affect disease progression. PMID:21832228

Curriculum enrichment with self-testing activities in development of fundamental movement skills of first-grade children in Greece.

PubMed

Karabourniotis, Dimitrios; Evaggelinou, Christina; Tzetzis, George; Kourtessis, Thomas

2002-06-01

The purpose of this study was to investigate the effect of self-testing activities on the development of fundamental movement skills in first-grade children in Greece. Two groups of children were tested. The Control group (n = 23 children) received the regular 12-wk. physical education school program and the Experimental group (n = 22 children) received a 12-wk. skill-oriented program with an increasing allotment of self-testing activities. The Test of Gross Motor Development was used to assess fundamental movement skills, while the content areas of physical education courses were estimated with an assessment protocol, based on the interval recording system called the Academic Learning Time-Physical Education. A 2 x 2 repeated measures analysis of variance with group as the between factor and testing time (pretest vs posttest) as the repeated-measures factor was performed to assess differences between the two groups. A significant interaction of group with testing time was found for the Test of Gross Motor Development total score, with the Experimental group scoring higher then the Control group. A significant main effect was also found for test but not for group. This study provides evidence supporting the notion that a balanced allotment of the self-testing and game activities beyond the usual curriculum increases the fundamental motor-skill development of children. Also, it stresses the necessity for content and performance standards for the fundamental motor skills in educational programs. Finally, it seems that the Test of Gross Motor Development is a useful tool for the assessment of children's fundamental movement skills.

Dynamics of Biomarkers in Relation to Aging and Mortality

PubMed Central

Arbeev, Konstantin G.; Ukraintseva, Svetlana V.; Yashin, Anatoliy I.

2016-01-01

Contemporary longitudinal studies collect repeated measurements of biomarkers allowing one to analyze their dynamics in relation to mortality, morbidity, or other health-related outcomes. Rich and diverse data collected in such studies provide opportunities to investigate how various socioeconomic, demographic, behavioral and other variables can interact with biological and genetic factors to produce differential rates of aging in individuals. In this paper, we review some recent publications investigating dynamics of biomarkers in relation to mortality, which use single biomarkers as well as cumulative measures combining information from multiple biomarkers. We also discuss the analytical approach, the stochastic process models, which conceptualizes several aging-related mechanisms in the structure of the model and allows evaluating “hidden” characteristics of aging-related changes indirectly from available longitudinal data on biomarkers and follow-up on mortality or onset of diseases taking into account other relevant factors (both genetic and non-genetic). We also discuss an extension of the approach, which considers ranges of “optimal values” of biomarkers rather than a single optimal value as in the original model. We discuss practical applications of the approach to single biomarkers and cumulative measures highlighting that the potential of applications to cumulative measures is still largely underused. PMID:27138087

Looking back on a half century of repeat magnetic measurements in France

NASA Astrophysics Data System (ADS)

Alexandrescu, Mioara Mandea; Gilder, Stuart; Courtillot, Vincent; Le Mouël, Jean Louis; Gilbert, Daniel

Birds do it. Bees do it. And with the discovery of lodestone over 2200 years ago, humans too could incorporate the Earth's magnetic field into their daily lives. Some of the oldest applications for tracking the magnetic field were in land and sea navigation. Magnetic field measurements quickly became an important economic factor in world trade, with documented use dating from the 11th century in China.The measurements are important in other applications as well. For example, rapid field variations are generated by solar activity and its interaction with the terrestrial environment. Large magnetic storms can disrupt satellite operation, communication systems, power transmission networks, and so forth [Campbell, 1997].Geomagnetism also provides a unique opportunity to explore the Earth's outer core, which is mostly liquid (molten) iron, where the field is generated. Field measurements can also yield valuable insights into the location of mineral deposits and aid in applications in the petroleum industry.

Brain-derived neurotrophic factor Val66Met genotype modulates amygdala habituation.

PubMed

Perez-Rodriguez, M Mercedes; New, Antonia S; Goldstein, Kim E; Rosell, Daniel; Yuan, Qiaoping; Zhou, Zhifeng; Hodgkinson, Colin; Goldman, David; Siever, Larry J; Hazlett, Erin A

2017-05-30

A deficit in amygdala habituation to repeated emotional stimuli may be an endophenotype of disorders characterized by emotion dysregulation, such as borderline personality disorder (BPD). Amygdala reactivity to emotional stimuli is genetically modulated by brain-derived neurotrophic factor (BDNF) variants. Whether amygdala habituation itself is also modulated by BDNF genotypes remains unknown. We used imaging-genetics to examine the effect of BDNF Val66Met genotypes on amygdala habituation to repeated emotional stimuli. We used functional magnetic resonance imaging (fMRI) in 57 subjects (19 BPD patients, 18 patients with schizotypal personality disorder [SPD] and 20 healthy controls [HC]) during a task involving viewing of unpleasant, neutral, and pleasant pictures, each presented twice to measure habituation. Amygdala responses across genotypes (Val66Met SNP Met allele-carriers vs. Non-Met carriers) and diagnoses (HC, BPD, SPD) were examined with ANOVA. The BDNF 66Met allele was significantly associated with a deficit in amygdala habituation, particularly for emotional pictures. The association of the 66Met allele with a deficit in habituation to unpleasant emotional pictures remained significant in the subsample of BPD patients. Using imaging-genetics, we found preliminary evidence that deficient amygdala habituation may be modulated by BDNF genotype. Copyright © 2017. Published by Elsevier B.V.

Pre-treatment red blood cell distribution width provides prognostic information in multiple myeloma.

PubMed

Zhou, Di; Xu, Peipei; Peng, Miaoxin; Shao, Xiaoyan; Wang, Miao; Ouyang, Jian; Chen, Bing

2018-06-01

The red blood cell distribution width (RDW), a credible marker for abnormal erythropoiesis, has recently been studied as a prognostic factor in oncology, but its role in multiple myeloma (MM) hasn't been thoroughly investigated. We performed a retrospective study in 162 patients with multiple myeloma. Categorical parameters were analyzed using Pearson chi-squared test. The Mann-Whitney and Wilcoxon tests were used for group comparisons. Comparisons of repeated samples data were analyzed with the general linear model repeated-measures procedure. The Kaplan-Meier product-limit method was used to determine OS and PFS, and the differences were assessed by the log-rank test. High RDW baseline was significantly associated with indexes including haemoglobin, bone marrow plasma cell infiltration, and cytogenetics risk stratification. After chemotherapy, the overall response rate (ORR) decreased as RDW baseline increased. In 24 patients with high RDW baseline, it was revealed RDW value decreased when patients achieved complete remission (CR), but increased when the disease progressed. The normal-RDW baseline group showed both longer overall survival (OS) and progression-free survival (PFS) than the high-RDW baseline group. Our study suggests pre-treatment RDW level is a prognostic factor in MM and should be regarded as an important parameter for assessment of therapeutic efficiency. Copyright © 2018. Published by Elsevier B.V.

Investigating intermolecular forces associated with thrombus initiation using optical tweezers

NASA Astrophysics Data System (ADS)

Arya, Maneesh; Lopez, Jose A.; Romo, Gabriel M.; Dong, Jing-Fei; McIntire, Larry V.; Moake, Joel L.; Anvari, Bahman

2002-05-01

Thrombus formation occurs when a platelet membrane receptor, glycoprotein (GP) Ib-IX-V complex, binds to its ligand, von Willebrand factor (vWf), in the subendothelium or plasma. To determine which GP Ib-IX-V amino acid sequences are critical for bond formation, we have used optical tweezers to measure forces involved in the binding of vWf to GP Ib-IX-V variants. Inasmuch as GP Ib(alpha) subunit is the primary component in human GP Ib-IX-V complex that binds to vWf, and that canine GP Ib(alpha) , on the other hand, does not bind to human vWf, we progressively replaced human GP Ib(alpha) amino acid sequences with canine GP Ib(alpha) sequences to determine the sequences essential for vWf/GP Ib(alpha) binding. After measuring the adhesive forces between optically trapped, vWf-coated beads and GP Ib(alpha) variants expressed on mammalian cells, we determined that leucine- rich repeat 2 of GP Ib(alpha) was necessary for vWf/GP Ib-IX- V bond formation. We also found that deletion of the N- terminal flanking sequence and leucine-rich repeat 1 reduced adhesion strength to vWf but did not abolish binding. While divalent cations are known to influence binding of vWf, addition of 1mM CaCl2 had no effect on measured vWf/GP Ib(alpha) bond strengths.

Measurement of factors that negatively influence the outcome of quitting smoking among patients with COPD: psychometric analyses of the Try To Quit Smoking instrument.

PubMed

Lundh, Lena; Alinaghizadeh, Hassan; Törnkvist, Lena; Gilljam, Hans; Galanti, Maria Rosaria

2014-12-01

To test internal consistency and factor structure of a brief instrument called Trying to Quit smoking. The most effective treatment for patients with chronic obstructive pulmonary disease is to quit smoking. Constant thoughts about quitting and repeated quit attempts can generate destructive feelings and make it more difficult to quit. Development and psychometric testing of the Trying to Quit smoking scale. The Trying to Quit smoking, an instrument designed to assess pressure-filled states of mind and corresponding pressure-relief strategies, was tested among 63 Swedish patients with chronic obstructive pulmonary disease. Among these, the psychometric properties of the instrument were analysed by Exploratory Factor Analyses. Fourteen items were included in the factor analyses, loading on three factors labelled: (1) development of pressure-filled mental states; (2) use of destructive pressure-relief strategies; and (3) ambivalent thoughts when trying to quit smoking. These three factors accounted for more than 80% of the variance, performed well on the Kaiser-Meyer-Olkin (KMO) test and had high internal consistency.

Notes From the Field: Secondary Task Precision for Cognitive Load Estimation During Virtual Reality Surgical Simulation Training.

PubMed

Rasmussen, Sebastian R; Konge, Lars; Mikkelsen, Peter T; Sørensen, Mads S; Andersen, Steven A W

2016-03-01

Cognitive load (CL) theory suggests that working memory can be overloaded in complex learning tasks such as surgical technical skills training, which can impair learning. Valid and feasible methods for estimating the CL in specific learning contexts are necessary before the efficacy of CL-lowering instructional interventions can be established. This study aims to explore secondary task precision for the estimation of CL in virtual reality (VR) surgical simulation and also investigate the effects of CL-modifying factors such as simulator-integrated tutoring and repeated practice. Twenty-four participants were randomized for visual assistance by a simulator-integrated tutor function during the first 5 of 12 repeated mastoidectomy procedures on a VR temporal bone simulator. Secondary task precision was found to be significantly lower during simulation compared with nonsimulation baseline, p < .001. Contrary to expectations, simulator-integrated tutoring and repeated practice did not have an impact on secondary task precision. This finding suggests that even though considerable changes in CL are reflected in secondary task precision, it lacks sensitivity. In contrast, secondary task reaction time could be more sensitive, but requires substantial postprocessing of data. Therefore, future studies on the effect of CL modifying interventions should weigh the pros and cons of the various secondary task measurements. © The Author(s) 2015.

Power of Models in Longitudinal Study: Findings from a Full-Crossed Simulation Design

ERIC Educational Resources Information Center

Fang, Hua; Brooks, Gordon P.; Rizzo, Maria L.; Espy, Kimberly Andrews; Barcikowski, Robert S.

2009-01-01

Because the power properties of traditional repeated measures and hierarchical multivariate linear models have not been clearly determined in the balanced design for longitudinal studies in the literature, the authors present a power comparison study of traditional repeated measures and hierarchical multivariate linear models under 3…

Near-Peer Teaching in Paramedic Education: A Repeated Measures Design

ERIC Educational Resources Information Center

Williams, Brett; Nguyen, David

2017-01-01

The transition of the Australian paramedic discipline from vocation education and training to the higher education sector has seen a sharp rise in interest in near-peer teaching (NPT). The objective of this study was to examine satisfaction levels of NPT over one academic semester among undergraduate paramedic students. A repeated measured design…

Omnibus Tests for Interactions in Repeated Measures Designs with Dichotomous Dependent Variables.

ERIC Educational Resources Information Center

Serlin, Ronald C.; Marascuilo, Leonard A.

When examining a repeated measures design with independent groups for a significant group by trial interaction, classical analysis of variance or multivariate procedures can be used if the assumptions underlying the tests are met. Neither procedure may be justified for designs with small sample sizes and dichotomous dependent variables. An omnibus…

Comparison of Two Procedures for Analyzing Small Sets of Repeated Measures Data

ERIC Educational Resources Information Center

Vallejo, Guillermo; Livacic-Rojas, Pablo

2005-01-01

This article compares two methods for analyzing small sets of repeated measures data under normal and non-normal heteroscedastic conditions: a mixed model approach with the Kenward-Roger correction and a multivariate extension of the modified Brown-Forsythe (BF) test. These procedures differ in their assumptions about the covariance structure of…

Evaluating the Performance of Repeated Measures Approaches in Replicating Experimental Benchmark Results

ERIC Educational Resources Information Center

McConeghy, Kevin; Wing, Coady; Wong, Vivian C.

2015-01-01

Randomized experiments have long been established as the gold standard for addressing causal questions. However, experiments are not always feasible or desired, so observational methods are also needed. When multiple observations on the same variable are available, a repeated measures design may be used to assess whether a treatment administered…

Repeatability estimates for oleoresin yield measurements in three species of the southern pines

Treesearch

James H. Roberds; Brain L. Strom

2006-01-01

Repeatability was estimated for constitutive oleoresin yield measurements in 10 stands of three species of pines native to southeastern United States. Trees of these species that discharge large quantities of oleoresin upon wounding are considered to be most resistant to attack by southern pine beetle (Dendroctonus frontalis Zimmermann). Oleoresin...

Analyzing Multivariate Repeated Measures Designs: A Comparison of Two Approximate Degrees of Freedom Procedures

ERIC Educational Resources Information Center

Lix, Lisa M.; Algina, James; Keselman, H. J.

2003-01-01

The approximate degrees of freedom Welch-James (WJ) and Brown-Forsythe (BF) procedures for testing within-subjects effects in multivariate groups by trials repeated measures designs were investigated under departures from covariance homogeneity and normality. Empirical Type I error and power rates were obtained for least-squares estimators and…

Counterbalancing and Other Uses of Repeated-Measures Latin-Square Designs: Analyses and Interpretations.

ERIC Educational Resources Information Center

Reese, Hayne W.

1997-01-01

Recommends that when repeated-measures Latin-square designs are used to counterbalance treatments across a procedural variable or to reduce the number of treatment combinations given to each participant, effects be analyzed statistically, and that in all uses, researchers consider alternative interpretations of the variance associated with the…

Limitations and challenges of EIT-based monitoring of stroke volume and pulmonary artery pressure.

PubMed

Braun, Fabian; Proença, Martin; Lemay, Mathieu; Bertschi, Mattia; Adler, Andy; Thiran, Jean-Philippe; Solà, Josep

2018-01-30

Electrical impedance tomography (EIT) shows potential for radiation-free and noninvasive hemodynamic monitoring. However, many factors degrade the accuracy and repeatability of these measurements. Our goal is to estimate the impact of this variability on the EIT-based monitoring of two important central hemodynamic parameters: stroke volume (SV) and pulmonary artery pressure (PAP). We performed simulations on a 4D ([Formula: see text]) bioimpedance model of a human volunteer to study the influence of four potential confounding factors (electrode belt displacement, electrode detachment, changes in hematocrit and lung air volume) on the performance of EIT-based SV and PAP estimation. Results were used to estimate how these factors affect the EIT measures of either absolute values or relative changes (i.e. trending). Our findings reveal that the absolute measurement of SV via EIT is very sensitive to electrode belt displacements and lung conductivity changes. Nonetheless, the trending ability of SV EIT might be a promising alternative. The timing-based measurement of PAP is more robust to lung conductivity changes but sensitive to longitudinal belt displacements at severe hypertensive levels and to rotational displacements (independent of the PAP level). We identify and quantify the challenges of EIT-based SV and PAP monitoring. Absolute SV via EIT is challenging, but trending is feasible, while both the absolute and trending of PAP via EIT are mostly impaired by belt displacements.

Measurement of central corneal thickness with optical low-coherence reflectometry and ultrasound pachymetry in normal and post-femtosecond laser in situ keratomileusis eyes.

PubMed

Huang, Jinhai; Liao, Na; Savini, Giacomo; Li, Yuanguang; Bao, Fangjun; Yu, Ye; Yu, Ayong; Wang, Qinmei

2015-02-01

To determine the repeatability and reproducibility of measurements of central corneal thickness (CCT) using optical low-coherence reflectometry (Lenstar LS900; Haag Streit) in normal eyes and post-femtosecond laser in situ keratomileusis (post-FS-LASIK) eyes and evaluate their agreement with ultrasound (US) pachymetry. CCT was measured using Lenstar and US pachymetry sequentially in normal and post-FS-LASIK eyes by 2 experienced observers. Intraoperator repeatability and interoperator reproducibility were assessed by within-subject standard deviation, test-retest repeatability, coefficient of variation (CoV), and intraclass correlation coefficient. Paired t-tests and Bland-Altman plots were used for analyzing agreement between the 2 devices. In this study, 55 healthy subjects and 50 post-FS-LASIK patients were recruited. Test-retest repeatability of Lenstar was within 10 μm, CoV was less than 1.0%, and intraclass correlation coefficient was more than 0.9 in both normal and post-FS-LASIK groups. Mean difference between these methods was 1.4 ± 4.2 μm and -1.7 ± 5.4 μm, respectively. Moreover, measurements of CCT showed narrow 95% limits of agreement (range, normal group: -6.8 and 9.6 μm; post-FS-LASIK group: -12.4 and 8.9 μm), which implied good agreement. Measurements of CCT using Lenstar showed excellent intraoperator repeatability and interoperator reproducibility both in normal eyes and post-FS-LASIK eyes. Measurements of CCT using Lenstar and US pachymetry showed good agreement and both can be used interchangeably.

Factors Contributing to Pelvis Instability in Female Adolescent Athletes During Unilateral Repeated Partial Squat Activity

PubMed Central

Scarborough, Donna Moxley; Linderman, Shannon; Berkson, Eric M.; Oh, Luke S.

2017-01-01

Objectives: Unilateral partial squat tasks are often used to assess athletes’ lower extremity (LE) neuromuscular control. Single squat biomechanics such as lateral drop of the non-stance limb’s pelvis have been linked to knee injury risk. Yet, there are limited studies on the factors contributing to pelvic instability during the unilateral partial squat such as anatomical alignment of the knee and hip strength. The purpose of this study was 1) to assess the influence of leg dominance on pelvic drop among female athletes during the repeated unilateral partial squat activity and 2) to investigate the contributions that lower limb kinematics and hip strength have on pelvis drop. Methods: 42 female athletes (27= softball pitchers, 15=gymnasts, avg age=16.48 ± 2.54 years) underwent lower limb assessment. The quadriceps angle (Q angle) and the average of 3 trials for hip abduction and extension strength (handheld dynamometer measurements) were used for analyses. 3D biomechanical analysis of the repeated unilateral partial squat activity followed using a 20 motion capture camera system which created a 15 segment model of each subject. The subject stood on one leg at the lateral edge of a 17.78 cm box with hands placed on the hips and squatted so that the free hanging contralateral limb came as close to the ground without contact for 5 continuous repetitions. One trial for each limb was performed. Peak pelvic drop and ankle, knee and hip angles and torques (normalized by weight) at this time point were calculated using Visual 3D (C-Motion) biomechanical software. Paired T-test, Spearman correlations and multiple regression model statistical analyses were performed. Results: Peak pelvic drop during the unilateral partial squat did not differ significantly on the basis of limb dominance (p=0.831, Dom: -3.40 ± 5.10° , ND: -3.46 ± 4.44°). Peak pelvic drop displayed a Spearman correlation with the functional measure of hip abduction/adduction (ABD/ADD) angle (rs= 0.627, p< 0.001) (Figure 1). No association was noted between peak pelvic drop and anatomical measures of Q angle or isometric hip extension strength. A multiple regression was performed to predict pelvis drop angle from the following 6 variables: isometric hip ABD strength, hip ABD/ADD angle, hip internal/external rotation angle, ankle supination/pronation (S/P) angle, height and weight. These variables statistically predicted pelvis drop, F(6,73) = 17.848, p < .0005, R2 = 0.595. The strongest combined predictor variables for pelvic drop in the female athletes were hip abduction/ adduction angle and strength followed by subject’s weight and ankle S/P angle (Table 1). Conclusion: Peak pelvic drop during the repeated unilateral partial squat activity did not correlate significantly with Q angle and hip extension strength. Instead, peak pelvic drop appears more related to a combination of biomechanical limb positioning, hip ABD strength and subject demographics. The regression model run on the repeated unilateral partial squat demonstrates predictive power of this dynamic assessment tool based on kinematic measures across multiple joints. Results could guide clinician screening for excessive pelvic drop in female athletes and based on the predictive model make recommendations for corrective conditioning to help prevent knee injury and guide return to sport following LE surgery. Table 1: Multivariate linear regression model for pelvic drop, Isometric hip strength and lower extremity kinematics during repeated partial squat activity among female athletes. Variable P Isometric hip abduction strength 0.034* Hip Abduction/Adduction Angle <0.001* Hip Internal/External Rotation Angle 0.936 Ankle Internal/External Rotation Angle 0.072 Height 0.398 Weight 0.011* * Level of significance established at p<0.05

Triglycerides as a biological marker of repeated re-hospitalization resulting from deliberate self-harm in acute psychiatry patients: a prospective observational study

PubMed Central

2014-01-01

Background Biological factors have been associated with deliberate self-harm (DSH) but have not been integrated with clinical factors in routine risk assessments. This study aimed to examine the incremental validity of lipid levels and platelet serotonin when combined with psychosocial factors in risk assessments for repeated admissions due to DSH. Methods In this prospective observational study of 196 acutely admitted patients, results of blood tests performed upon admission and the MINI Suicidal Scale and psychosocial DSH risk factor assessments performed at discharge were compared with the incidence of DSH recorded during the first 3 and 12 months after discharge. Results High triglyceride levels were found to be a significant marker for patients admitted 3 or more times due to DSH (repeated DSH, DSH-R) when tested against other significant risk factors. When all (9) significant univariate factors associated with 12-month post-discharge DSH-R were analyzed in a multivariate logistic regression, the MINI Suicidal Scale (p = 0.043), a lack of insight (p = 0.040), and triglyceride level (p = 0.020) remained significant. The estimated 12-month area under the curve of the receiver operator characteristic (ROC-AUC) for DSH-R was 0.74 for triglycerides, 0.81 for the MINI, 0.89 for the MINI + psychosocial factors, and 0.91 for the MINI + psychosocial factors + triglycerides. The applied multifaceted approach also significantly discriminated between 12-month post-discharge DSH-R patients and other DSH patients, and a lack of insight (p = 0.047) and triglycerides (p = 0.046) remained significant for DSH-R patients in a multivariate analysis in which other DSH patients served as the reference group (rather than non-DSH patients). Conclusion The triglyceride values provided incremental validity to the MINI Suicidal Scale and psychosocial risk factors in the assessment of the risk of repeated DSH. Therefore, a bio-psychosocial approach appears promising, but further research is necessary to refine and validate this method. PMID:24568671

Design ATE systems for complex assemblies

NASA Astrophysics Data System (ADS)

Napier, R. S.; Flammer, G. H.; Moser, S. A.

1983-06-01

The use of ATE systems in radio specification testing can reduce the test time by approximately 90 to 95 percent. What is more, the test station does not require a highly trained operator. Since the system controller has full power over all the measurements, human errors are not introduced into the readings. The controller is immune to any need to increase output by allowing marginal units to pass through the system. In addition, the software compensates for predictable, repeatable system errors, for example, cabling losses, which are an inherent part of the test setup. With no variation in test procedures from unit to unit, there is a constant repeatability factor. Preparing the software, however, usually entails considerable expense. It is pointed out that many of the problems associated with ATE system software can be avoided with the use of a software-intensive, or computer-intensive, system organization. Its goal is to minimize the user's need for software development, thereby saving time and money.

NIST mixed stain study 3: signal intensity balance in commercial short tandem repeat multiplexes.

PubMed

Duewer, David L; Kline, Margaret C; Redman, Janette W; Butler, John M

2004-12-01

Short-tandem repeat (STR) allelic intensities were collected from more than 60 forensic laboratories for a suite of seven samples as part of the National Institute of Standards and Technology-coordinated 2001 Mixed Stain Study 3 (MSS3). These interlaboratory challenge data illuminate the relative importance of intrinsic and user-determined factors affecting the locus-to-locus balance of signal intensities for currently used STR multiplexes. To varying degrees, seven of the eight commercially produced multiplexes used by MSS3 participants displayed very similar patterns of intensity differences among the different loci probed by the multiplexes for all samples, in the hands of multiple analysts, with a variety of supplies and instruments. These systematic differences reflect intrinsic properties of the individual multiplexes, not user-controllable measurement practices. To the extent that quality systems specify minimum and maximum absolute intensities for data acceptability and data interpretation schema require among-locus balance, these intrinsic intensity differences may decrease the utility of multiplex results and surely increase the cost of analysis.

Evidence for a Sudden Magnetic Field Reconfiguration in Soft Gamma Repeater 1900+14

NASA Technical Reports Server (NTRS)

Woods, Peter M.; Kouveliotou, Chryssa; Gogus, Ersin; Finger, Mark H.; Swank, Jean; Smith, Don A.; Hurley, Kevin; Thompson, Christopher

2001-01-01

We report the detection of large flux changes in the persistent X-ray flux of soft gamma repeater (SGR) 1900 + 14 during its burst active episode in 1998. Most notably, we find a factor of approx. 700 increase in the nonburst X-ray flux following the August 27 flare, which decayed in time as a power law. Our measurements indicate that the pulse fraction remains constant throughout this decay. This suggests a global flux enhancement as a consequence of the August 27 flare rather than localized heating. While the persistent flux has since recovered to the preoutburst level, the pulse profile has not. The pulse shape changed to a near sinusoidal profile within the tail of the August 27 flare (in gamma-rays), and this effect has persisted for more than 1.5 years (in X-rays). The results presented here suggest that the magnetic field of the neutron star in SGR 1900 + 14 was significantly altered (perhaps globally) during the giant flare of August 27.

Previous tubal ectopic pregnancy raises the incidence of repeated ectopic pregnancies in in vitro fertilization-embryo transfer patients.

PubMed

Weigert, Monika; Gruber, Diego; Pernicka, Elisabeth; Bauer, Peter; Feichtinger, Wilfried

2009-01-01

To investigate the incidence of Tubal Ectopic Pregnancies (TEP) in IVF-ET patients with respect to the status of the fallopian tubes after a previous TEP. This retrospective study compares patients undergoing 481 IVF-ET cycles after conservatively or surgically treated TEP(s) with a Control Group (idiopathic or male factor for IVF-ET indication). Medical reports of surgery and/or hysterosalpingograms prior to the IVF cycles classified the status of the fallopian tubes. 12 TEPs (8.95%/Pregnancies (PR)) occurred in the Study Group. In the Control Group one TEP (0.75%/PR; p < 0.001) was found. Smoking increased the probability of TEPs (p = 0.0028) and of pathological pregnancies (abortion, biochemical and ectopic PR; (p = 0.0411)). For statistic evolution logistic regression (PROC GENMOD) and a repeated measure model were applied. Women with a previous TEP should be informed about the significantly increased risk for a further TEP in IVF-ET treatment, especially if they are smoking.

Tracheal Wall Thickening Is Associated with the Granulation Tissue Formation Around Silicone Stents in Patients with Post-Tuberculosis Tracheal Stenosis

PubMed Central

Eom, Jung Seop; Jeon, Kyeongman; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young; Chung, Man Pyo; Kwon, O Jung

2013-01-01

Purpose Tracheal restenosis due to excessive granulation tissue around a silicone stent requires repeated bronchoscopic interventions in patients with post-tuberculosis tracheal stenosis (PTTS). The current study was conducted to identify the risk factors for granulation tissue formation after silicone stenting in PTTS patients. Materials and Methods A retrospective study was conducted between January 1998 and December 2010. Forty-two PTTS patients with silicone stenting were selected. Clinical and radiological variables were retrospectively collected and analyzed. Results Tracheal restenosis due to granulation tissue formation were found in 20 patients (47.6%), and repeated bronchoscopic interventions were conducted. In multivariate analysis, tracheal wall thickness, measured on axial computed tomography scan, was independently associated with granulation tissue formation after silicone stenting. Furthermore, the degree of tracheal wall thickness was well correlated with the degree of granulation tissue formation. Conclusion Tracheal wall thickening was associated with granulation tissue formation around silicone stents in patients with post-tuberculosis tracheal stenosis. PMID:23709431

Tracheal wall thickening is associated with the granulation tissue formation around silicone stents in patients with post-tuberculosis tracheal stenosis.

PubMed

Eom, Jung Seop; Kim, Hojoong; Jeon, Kyeongman; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young; Chung, Man Pyo; Kwon, O Jung

2013-07-01

Tracheal restenosis due to excessive granulation tissue around a silicone stent requires repeated bronchoscopic interventions in patients with post-tuberculosis tracheal stenosis (PTTS). The current study was conducted to identify the risk factors for granulation tissue formation after silicone stenting in PTTS patients. A retrospective study was conducted between January 1998 and December 2010. Forty-two PTTS patients with silicone stenting were selected. Clinical and radiological variables were retrospectively collected and analyzed. Tracheal restenosis due to granulation tissue formation were found in 20 patients (47.6%), and repeated bronchoscopic interventions were conducted. In multivariate analysis, tracheal wall thickness, measured on axial computed tomography scan, was independently associated with granulation tissue formation after silicone stenting. Furthermore, the degree of tracheal wall thickness was well correlated with the degree of granulation tissue formation. Tracheal wall thickening was associated with granulation tissue formation around silicone stents in patients with post-tuberculosis tracheal stenosis.

Measurements of the radiation quality factor Q at aviation altitudes during solar minimum (2006-2008)

NASA Astrophysics Data System (ADS)

Meier, Matthias M.; Hubiak, Melina

2010-05-01

In radiation protection, the Q-factor has been defined to describe the biological effectiveness of the energy deposition or absorbed dose to humans in the mixed radiation fields at aviation altitudes. This particular radiation field is generated by the interactions of primary cosmic particles with the atoms of the constituents of the Earth’s atmosphere. Thus the intensity, characterized by the ambient dose equivalent rate H∗(10), depends on the flight altitude and the energy spectra of the particles, mainly protons and alpha particles, impinging on the atmosphere. These charged cosmic projectiles are deflected both by the interplanetary and the Earth’s magnetic field such that the corresponding energy spectra are modulated by these fields. The solar minimum is a time period of particular interest since the interplanetary magnetic field is weakest within the 11-year solar cycle and the dose rates at aviation altitudes reach their maximum due to the reduced shielding of galactic cosmic radiation. For this reason, the German Aerospace Center (DLR) performed repeated dosimetric on-board measurements in cooperation with several German airlines during the past solar minimum from March 2006 to August 2008. The Q-factors measured with a TEPC range from 1.98 at the equator to 2.60 in the polar region.

Reproducibility of regional DEXA examinations of abdominal fat and lean tissue.

PubMed

Tallroth, Kaj; Kettunen, Jyrki A; Kujala, Urho M

2013-01-01

The aim of this study was to develop and test the validity of a new repeatable method to delimit abdominal areas for follow-up of fat mass (FM) and lean tissue mass (LM) in DEXA examinations. 37 male volunteers underwent two DEXA examinations. Total body FM and LM measurements and corresponding abdominal measurements in a carefully defined region were calculated from the first scan. After repositioning of the subjects and a second scan, the delimited region was copied and the abdominal tissues re-calculated. The mean LM of the abdominal area was 2.804 kg (SD 0.556), and the mean FM was 1.026 kg (SD 0.537). The intra-class correlation coefficient for the repeated abdominal LM, FM, and LM/FM ratio measurements was 0.99. The mean difference (bias) for the repeated abdominal LM measurements was -13 g (95% confidence interval (CI) -193.0 to 166.8), and for the repeated abdominal FM measurements it was -35 g (95% CI -178.9 to 108.5). The results indicate that regional DEXA is a sensitive method with excellent reproducibility in the measurements of the abdominal fat and lean tissues. The method may serve as a useful tool for evaluation and follow-up of various dietary and training programmes.

Reproducibility of Regional DEXA Examinations of Abdominal Fat and Lean Tissue

PubMed Central

Tallroth, Kaj; Kettunen, Jyrki A.; Kujala, Urho M.

2013-01-01

Objective The aim of this study was to develop and test the validity of a new repeatable method to delimit abdominal areas for follow-up of fat mass (FM) and lean tissue mass (LM) in DEXA examinations. Methods 37 male volunteers underwent two DEXA examinations. Total body FM and LM measurements and corresponding abdominal measurements in a carefully defined region were calculated from the first scan. After repositioning of the subjects and a second scan, the delimited region was copied and the abdominal tissues re-calculated. Results The mean LM of the abdominal area was 2.804 kg (SD 0.556), and the mean FM was 1.026 kg (SD 0.537). The intra-class correlation coefficient for the repeated abdominal LM, FM, and LM/FM ratio measurements was 0.99. The mean difference (bias) for the repeated abdominal LM measurements was −13 g (95% confidence interval (CI) −193.0 to 166.8), and for the repeated abdominal FM measurements it was −35 g (95% CI −178.9 to 108.5). Conclusions The results indicate that regional DEXA is a sensitive method with excellent reproducibility in the measurements of the abdominal fat and lean tissues. The method may serve as a useful tool for evaluation and follow-up of various dietary and training programmes. PMID:23615566

Repeated Reading, Turn Taking, and Augmentative and Alternative Communication (AAC)

ERIC Educational Resources Information Center

Edmister, Evette; Wegner, Jane

2015-01-01

This single participant multiple baseline research design measured the effects of repeatedly reading narrative books to children who used voice output augmentative communication devices to communicate. The study sought to determine if there was a difference observed in the number of turns taken when reading stories repeatedly. Three girls ranging…

Repeatability of paired counts.

PubMed

Alexander, Neal; Bethony, Jeff; Corrêa-Oliveira, Rodrigo; Rodrigues, Laura C; Hotez, Peter; Brooker, Simon

2007-08-30

The Bland and Altman technique is widely used to assess the variation between replicates of a method of clinical measurement. It yields the repeatability, i.e. the value within which 95 per cent of repeat measurements lie. The valid use of the technique requires that the variance is constant over the data range. This is not usually the case for counts of items such as CD4 cells or parasites, nor is the log transformation applicable to zero counts. We investigate the properties of generalized differences based on Box-Cox transformations. For an example, in a data set of hookworm eggs counted by the Kato-Katz method, the square root transformation is found to stabilize the variance. We show how to back-transform the repeatability on the square root scale to the repeatability of the counts themselves, as an increasing function of the square mean root egg count, i.e. the square of the average of square roots. As well as being more easily interpretable, the back-transformed results highlight the dependence of the repeatability on the sample volume used.

Measurement area and repeatability of semiautomated assessment of corneal endothelium in the Topcon specular microscope SP-2000P and IMAGEnet system.

PubMed

Ding, Xiaohu; Huang, Qunxiao; Zheng, Yingfeng; Jiang, Yuzhen; Huang, Shengsong; He, Mingguang

2012-10-01

To investigate the repeatability of the semiautomatic assessment of corneal endothelial cells and its association with the measurement area in the Topcon SP-2000P microscope and IMAGEnet system. Specular microscopic images of 86 healthy subjects were captured and analyzed using the Topcon SP-2000P microscope and IMAGEnet system. The same images were analyzed twice, on separate days, by the same examiner using the built-in measurement tool of the IMAGEnet system. The measurement areas were defined with a frame mounted on a computer screen. Four different-sized measurement areas were chosen for the semiautomatic measurements: box A (5.4 × 13.9 cm(2)), box B (4 × 10 cm(2)), box C (4 × 7 cm(2)), and box D (2 × 5 cm(2)). Average cell size (ACS), endothelial cell density (ECD), coefficient of variance, and hexagonality were measured. Repeatability was assessed based on the limit of agreement (LOA). The means of ACS, ECD, and hexagonality were not statistically different across 4 measurement areas (analysis of variance, P > 0.05). The mean differences (bias) were modest for ACS (range, -1.9∼3.9 μm(2)), ECD (range, -27.2∼14.6 cells per square millimeter), coefficient of variance (range, -0.14∼1.00), and hexagonality (range, -1.3%∼6.8%). Limits of agreement (mean difference ± 1.96× SD) were greater in the measurements with smaller areas: limit of agreement values for ECD were 14.6 ± 99.6, -3.8 ± 101.1, -27.2 ± 179, and -15.8 ± 488 cells per square millimeter for boxes A, B, C, and D, respectively. Similar trends were found in the repeatability of ACS and hexagonality. Repeatability is improved when larger measurement areas are chosen.

How to measure kyphosis in everyday clinical practice: a reliability study on different methods.

PubMed

Zaina, Fabio; Donzelli, Sabrina; Lusini, Monia; Negrini, Stefano

2012-01-01

The sagittal plane measures have a relevant role both in Idiopathic Scoliosis (AIS) and in Hyperkyphosis (HK) management. Nevertheless, clinical tools for everyday use are scarce and not adequately studied. To assess the repeatability of different methods for the collection of the sagittal profile of patients with spinal deformities during everyday clinics. We performed 4 different studies in 4 different populations of AIS and HK patients. In the first study we reported the normative data and measurement error of the plumbline measures in a general population of 180 adolescents. In the second study we compared the sagittal distances from the plumbline of C7, T12, L3, and Sagittal Index (SI = C7+L3) with the measures of the Video Rasterstereography at the same levels and the angles of kyphosis and lordosis in 100 AIS patients. In the third study we evaluated the intra and inter-rater repeatability and the measurement error of kyphosis and lordosis angles measured with the Inclimed in 100 AIS patients. In the last study we evaluated the repeatability of the sagittal distances from the plumbline, by using a 1 mm change instead of 5 mm in a population of 40 patients. repeatability has been evaluated according to Bland and Altman, to identify the limits of variation that are clinically significant. Results. Study 1: the normative data were: females: 34 ± 11 mm for C7; 34 ± 15 mm for L3, males: 34 ± 10 mm for C7; 48 ± 10 mm for L3;. Study 2: a coefficient of correlation was calculated in order to compare measures. Study 3: the k value for Inclimed varied from fair to good. Study 4: the repeatability was fair for this measure. Some clinical instruments are now available for sagittal plane assessment in AIS and hyperkyphosis. The results of the present study report the limits during measurements in a clinical setting of parameters that are routinely collected by some clinicians.

Characterization of Upper Eyelid Tarsus and Lid Wiper Dimensions.

PubMed

Navascues-Cornago, Maria; Maldonado-Codina, Carole; Gupta, Ruchi; Morgan, Philip B

2016-09-01

To measure various dimensions of the upper tarsal plate and the area of upper lid wiper staining. The repeatability of the method of measurement was investigated. Thirty-five healthy non-contact lens wearers were enrolled. The following parameters were measured from digital images of the upper eyelid captured with a slitlamp camera: length, height, and total area of the tarsal plate and area of lid wiper staining (lissamine green). Measurements were performed in a randomized and masked fashion on two separate occasions by the same investigator using ImageJ (National Institutes of Health). Coefficients of repeatability (COR) were calculated. The dimensions (mean±SD) of the tarsal plate were 20.6±1.9 mm length, 7.9±0.8 mm height, and 103.3±18.8 mm total area. The area of lid wiper staining was 2.7±2.0 mm. No association was found between tarsal dimensions and lid wiper staining (all P>0.05). Image analysis COR values were 0.6 mm tarsal length, 0.1 mm tarsal height, 1.2 mm tarsal area, and 0.4 mm lid wiper staining. There was no significant difference between repeated measurements for any parameter (all P>0.05). Limits of agreement were narrow for all parameters, indicating good agreement between repeated measurements. This work has demonstrated that there is a wide range in the dimensions of the upper tarsal plate in an urban UK population. No association was found between the upper tarsal dimensions and lid wiper staining. ImageJ was shown to be a repeatable method to measure the dimensions of the upper tarsal plate and upper lid wiper staining.

Inflammatory gene changes associated with the repeated-bout effect.

PubMed

Hubal, Monica J; Chen, Trevor C; Thompson, Paul D; Clarkson, Priscilla M

2008-05-01

This study proposed that attenuated expression of inflammatory factors is an underlying mechanism driving the repeated-bout effect (rapid adaptation to eccentric exercise). We investigated changes in mRNA levels and protein localization of inflammatory genes after two bouts of muscle-lengthening exercise. Seven male subjects performed two bouts of lower body exercise (separated by 4 wk) in which one leg performed 300 eccentric-concentric actions, and the contralateral leg performed 300 concentric actions only. Vastus lateralis biopsies were collected at 6 h, and strength was assessed at baseline and at 0, 3, and 5 days after exercise. mRNA levels were measured via semiquantitative RT-PCR for the following genes: CYR61, HSP40, HSP70, IL1R1, TCF8, ZFP36, CEBPD, and MCP1. Muscle functional adaptation was demonstrated via attenuated strength loss (16% less, P = 0.04) at 5 days after bout 2 compared with bout 1 in the eccentrically exercised leg. mRNA expression of three of the eight genes tested was significantly elevated in the eccentrically exercised leg from bout 1 to bout 2 (+3.9-fold for ZFP36, +2.3-fold for CEBPD, and +2.6-fold for MCP1), while all eight mRNA levels were unaffected by bout in the concentrically exercised leg. Immunohistochemistry further localized the protein of one of the elevated factors [monocyte chemoattractant protein-1 (MCP1)] within the tissue. MCP1 colocalized with resident macrophage and satellite cell populations, suggesting that alterations in cytokine signaling between these cell populations may play a role in muscle adaptation to exercise. Contrary to our hypothesis, several inflammatory genes were transcriptionally upregulated (rather than attenuated) after a repeated exercise bout, potentially indicating a role for these genes in the adaptation process.

Does insulin-like growth factor 1 genotype influence muscle power response to strength training in older men and women?

PubMed

Sood, Suchi; Hanson, Erik D; Delmonico, Matthew J; Kostek, Matthew C; Hand, Brian D; Roth, Stephen M; Hurley, Ben F

2012-02-01

The CA-repeat polymorphism in the insulin-like growth factor 1 (IGF1) gene promoter region has been associated with strength and circulating IGF-I protein levels. The purpose of the study was to determine if the IGF1 CA-repeat polymorphism influences muscle power at baseline and in response to ST in older adults. Knee extensor peak power (PP) was measured at 50, 60, and 70% of 1-RM strength before and after 10 weeks of unilateral knee extensor ST in older adults, aged 50-85 years, to determine the changes in absolute and relative PP with ST. Subjects (N = 114) were genotyped for the IGF1 CA-repeat polymorphism and grouped as homozygous for the 192 allele, heterozygous, or non-carriers of the 192 allele. The 192 homozygotes had significantly lower baseline PP at 50, 60, and 70% of 1-RM strength than the non-carriers when age, sex, and baseline fat-free mass were covaried (all P < 0.05). This same relationship was observed when the highest PP within these ranges was compared (e.g., 317.6 ± 13.5 for 192 homozygotes and 380.2 ± 16.3 for non-carriers of the 192 allele, P < 0.05). Both absolute and relative PP increased significantly with ST in all genotype groups as expected, but there were no significant relationships among IGF1 genotypes and any of the PP changes. Despite a significant relationship between IGF1 genotype and knee extensor peak power at baseline, IGF1 genotype does not appear to influence changes in knee extensor peak power with ST.

Feasibility and acceptability of cell phone diaries to measure HIV risk behavior among female sex workers.

PubMed

Roth, Alexis M; Hensel, Devon J; Fortenberry, J Dennis; Garfein, Richard S; Gunn, Jayleen K L; Wiehe, Sarah E

2014-12-01

Individual, social, and structural factors affecting HIV risk behaviors among female sex workers (FSWs) are difficult to assess using retrospective surveys methods. To test the feasibility and acceptability of cell phone diaries to collect information about sexual events, we recruited 26 FSWs in Indianapolis, Indiana (US). Over 4 weeks, FSWs completed twice daily digital diaries about their mood, drug use, sexual interactions, and daily activities. Feasibility was assessed using repeated measures general linear modeling and descriptive statistics examined event-level contextual information and acceptability. Of 1,420 diaries expected, 90.3 % were completed by participants and compliance was stable over time (p > .05 for linear trend). Sexual behavior was captured in 22 % of diaries and participant satisfaction with diary data collection was high. These data provide insight into event-level factors impacting HIV risk among FSWs. We discuss implications for models of sexual behavior and individually tailored interventions to prevent HIV in this high-risk group.

Longitudinal Association of HIV Conspiracy Beliefs with Sexual Risk Among Black Males Living with HIV

PubMed Central

Galvan, Frank H.; Wagner, Glenn J.; Klein, David J.

2010-01-01

Research is needed to identify culturally relevant factors that may contribute to sexual risk among African Americans. We investigated HIV-specific medical mistrust as one such cultural factor, often exhibited as conspiracy beliefs about HIV (e.g., “AIDS was produced in a government laboratory”), which may be indicative of general suspicion of HIV treatment and prevention messages. Over a 6-month time-period, we measured endorsement of HIV conspiracy beliefs three times and frequency of condom use monthly among 181 HIV-positive African American males. A hierarchical multivariate repeated-measures logistic random effects model indicated that greater belief in HIV conspiracies was associated with a higher likelihood of reporting unprotected intercourse across all time-points. An average of 54% of participants who endorsed conspiracies reported unprotected intercourse, versus 39% who did not endorse conspiracies. Secondary prevention interventions may need to address medical mistrust as a contributor to sexual risk among African Americans living with HIV. PMID:20734227

Characterization of Soft Contact Lens Fitting Using Ultra-Long Scan Depth Optical Coherence Tomography

PubMed Central

Li, Ming; Lu, Fan

2017-01-01

Objectives To evaluate the centration and movement of soft contact lenses and to verify the repeatability of two repeated measurements of the lens centration and movement using ultra-long scan depth optical coherence tomography (UL-OCT). Methods A 1-day Acuvue® Define™ lens was tested on both eyes of 10 subjects (5 males and 5 females; mean age, 31.6 years). The centration and blink-induced movement of the contact lens were measured using UL-OCT at 5 min and 30 min after insertion. The measurements were repeated once at each checkpoint. Results Good repeatability was found in the lens centration and movement between the two repeated measurements at either checkpoint. The values of the lens movement were 0.457 ± 0.248 mm and 0.402 ± 0.229 mm at 5 min and decreased to 0.197 ± 0.065 mm and 0.211 ± 0.110 mm at 30 min after insertion for the right and left eyes, respectively (P < 0.05). Conclusions The custom-built UL-OCT presented good repeatability of centration and movement in Define lenses at 5 min and 30 min after insertion. Most of the lenses were centered temporal and inferior to the cornea during the first 30 min wearing period. Compared with 5 min after insertion, the lens was centered better and exhibited less movement at 30 min. PMID:28751981

High SNR Acquisitions Improve the Repeatability of Liver Fat Quantification Using Confounder-corrected Chemical Shift-encoded MR Imaging

PubMed Central

Motosugi, Utaroh; Hernando, Diego; Wiens, Curtis; Bannas, Peter; Reeder, Scott. B

2017-01-01

Purpose: To determine whether high signal-to-noise ratio (SNR) acquisitions improve the repeatability of liver proton density fat fraction (PDFF) measurements using confounder-corrected chemical shift-encoded magnetic resonance (MR) imaging (CSE-MRI). Materials and Methods: Eleven fat-water phantoms were scanned with 8 different protocols with varying SNR. After repositioning the phantoms, the same scans were repeated to evaluate the test-retest repeatability. Next, an in vivo study was performed with 20 volunteers and 28 patients scheduled for liver magnetic resonance imaging (MRI). Two CSE-MRI protocols with standard- and high-SNR were repeated to assess test-retest repeatability. MR spectroscopy (MRS)-based PDFF was acquired as a standard of reference. The standard deviation (SD) of the difference (Δ) of PDFF measured in the two repeated scans was defined to ascertain repeatability. The correlation between PDFF of CSE-MRI and MRS was calculated to assess accuracy. The SD of Δ and correlation coefficients of the two protocols (standard- and high-SNR) were compared using F-test and t-test, respectively. Two reconstruction algorithms (complex-based and magnitude-based) were used for both the phantom and in vivo experiments. Results: The phantom study demonstrated that higher SNR improved the repeatability for both complex- and magnitude-based reconstruction. Similarly, the in vivo study demonstrated that the repeatability of the high-SNR protocol (SD of Δ = 0.53 for complex- and = 0.85 for magnitude-based fit) was significantly higher than using the standard-SNR protocol (0.77 for complex, P < 0.001; and 0.94 for magnitude-based fit, P = 0.003). No significant difference was observed in the accuracy between standard- and high-SNR protocols. Conclusion: Higher SNR improves the repeatability of fat quantification using confounder-corrected CSE-MRI. PMID:28190853

Repeatability and consistency of individual behaviour in juvenile and adult Eurasian harvest mice

NASA Astrophysics Data System (ADS)

Schuster, Andrea C.; Carl, Teresa; Foerster, Katharina

2017-04-01

Knowledge on animal personality has provided new insights into evolutionary biology and animal ecology, as behavioural types have been shown to affect fitness. Animal personality is characterized by repeatable and consistent between-individual behavioural differences throughout time and across different situations. Behavioural repeatability within life history stages and consistency between life history stages should be checked for the independence of sex and age, as recent data have shown that males and females in some species may differ in the repeatability of behavioural traits, as well as in their consistency. We measured the repeatability and consistency of three behavioural and one cognitive traits in juvenile and adult Eurasian harvest mice ( Micromys minutus). We found that exploration, activity and boldness were repeatable in juveniles and adults. Spatial recognition measured in a Y Maze was only repeatable in adult mice. Exploration, activity and boldness were consistent before and after maturation, as well as before and after first sexual contact. Data on spatial recognition provided little evidence for consistency. Further, we found some evidence for a litter effect on behaviours by comparing different linear mixed models. We concluded that harvest mice express animal personality traits as behaviours were repeatable across sexes and consistent across life history stages. The tested cognitive trait showed low repeatability and was less consistent across life history stages. Given the rising interest in individual variation in cognitive performance, and in its relationship to animal personality, we suggest that it is important to gather more data on the repeatability and consistency of cognitive traits.

Trinucleotide repeat length and progression of illness in Huntington's disease.

PubMed

Kieburtz, K; MacDonald, M; Shih, C; Feigin, A; Steinberg, K; Bordwell, K; Zimmerman, C; Srinidhi, J; Sotack, J; Gusella, J

1994-11-01

The genetic defect causing Huntington's disease (HD) has been identified as an unstable expansion of a trinucleotide (CAG) repeat sequence within the coding region of the IT15 gene on chromosome 4. In 50 patients with manifest HD who were evaluated prospectively and uniformly, we examined the relationship between the extent of the DNA expansion and the rate of illness progression. Although the length of CAG repeats showed a strong inverse correlation with the age at onset of HD, there was no such relationship between the number of CAG repeats and the rate of clinical decline. These findings suggest that the CAG repeat length may influence or trigger the onset of HD, but other genetic, neurobiological, or environmental factors contribute to the progression of illness and the underlying pace of neuronal degeneration.

Intolerance of uncertainty as the vulnerability factor among parents of childhood cancer survivors: A 3-month follow-up study.

PubMed

Vander Haegen, Marie; Etienne, Anne-Marie

2018-05-14

In a 3-month follow-up study, we assessed the intolerance of uncertainty in 61 parents of a childhood cancer survivor. The objective was to compare its prevalence over time. We tested these parents twice i.e., at treatment completion (time 1) and 3 months later (time 2). We hypothesized that this personality factor stayed stable and had aversive effects on cognitive processes. Noticeable intolerance of uncertainty rates were found. At both assessments, results showed that this factor was central in the development of excessive worries, poor problem orientation, rumination, cognitive avoidance and positive beliefs about worry. Repeated measures revealed a decrease for anxiety and cognitive avoidance, and an increased level for somatic symptoms. Parents who are intolerant of uncertainty are at risk to display dysfunctional behaviors over time. Sensitizing health care professionals to the identification of this factor and its associated difficulties is essential for the implementation of efficient intervention strategies.

Calibrators measurement system for headlamp tester of motor vehicle base on machine vision

NASA Astrophysics Data System (ADS)

Pan, Yue; Zhang, Fan; Xu, Xi-ping; Zheng, Zhe

2014-09-01

With the development of photoelectric detection technology, machine vision has a wider use in the field of industry. The paper mainly introduces auto lamps tester calibrator measuring system, of which CCD image sampling system is the core. Also, it shows the measuring principle of optical axial angle and light intensity, and proves the linear relationship between calibrator's facula illumination and image plane illumination. The paper provides an important specification of CCD imaging system. Image processing by MATLAB can get flare's geometric midpoint and average gray level. By fitting the statistics via the method of the least square, we can get regression equation of illumination and gray level. It analyzes the error of experimental result of measurement system, and gives the standard uncertainty of synthesis and the resource of optical axial angle. Optical axial angle's average measuring accuracy is controlled within 40''. The whole testing process uses digital means instead of artificial factors, which has higher accuracy, more repeatability and better mentality than any other measuring systems.

Reliability of laboratory measurement of human food intake.

PubMed

Laessle, R; Geiermann, L

2012-02-01

The universal eating monitor (UEM) of Kissileff for laboratory measurement of food intake was modified and used with a newly developed special software to compute cumulative intake data. To explore the measurement precision of the UEM an investigation of test-retest-reliability of food intake parameters was conducted. The intake characteristics of 125 males and females were measured repeatedly in the laboratory with a measurement interval of 1 week. Pudding of preferred flavour served as test meal. Test-retest-reliability of intake characteristics ranged from .49 (change of eating rate) to .89 (initial eating rate). All test-retest correlations were highly significant. Sex, BMI and eating habits according to TFEQ-factors had no significant effects on reliability of intake characteristics. The test-retest-reliability of the laboratory intake measures is as good as those of personality questionnaires, where it should be better than .80. Reliability coefficients are valid independent of sex, BMI or trait characteristics of eating behaviour. Copyright © 2011 Elsevier Ltd. All rights reserved.

Reproducibility of functional volume and activity concentration in 18F-FDG PET/CT of liver metastases in colorectal cancer.

PubMed

Heijmen, Linda; de Geus-Oei, Lioe-Fee; de Wilt, Johannes H W; Visvikis, Dimitris; Hatt, Mathieu; Visser, Eric P; Bussink, Johan; Punt, Cornelis J A; Oyen, Wim J G; van Laarhoven, Hanneke W M

2012-12-01

Several studies showed potential for monitoring response to systemic therapy in metastatic colorectal cancer patients with (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Before (18)F-FDG PET can be implemented for response evaluation the repeatability should be known. This study was performed to assess the magnitude of the changes in standardized uptake value (SUV), volume and total lesion glycolysis (TLG) in colorectal liver metastases and validate the biological basis of (18)F-FDG PET in colorectal liver metastases. Twenty patients scheduled for liver metastasectomy underwent two (18)F-FDG PET scans within 1 week. Bland-Altman analysis was performed to assess repeatability of SUV(max), SUV(mean), volume and TLG. Tumours were delineated using an adaptive threshold method (PET(SBR)) and a semiautomatic fuzzy locally adaptive Bayesian (FLAB) delineation method. Coefficient of repeatability of SUV(max) and SUV(mean) were ∼39 and ∼31 %, respectively, independent of the delineation method used and image reconstruction parameters. However, repeatability was worse in recently treated patients. The FLAB delineation method improved the repeatability of the volume and TLG measurements compared to PET(SBR), from coefficients of repeatability of over 85 % to 45 % and 57 % for volume and TLG, respectively. Glucose transporter 1 (GLUT1) expression correlated to the SUV(mean). Vascularity (CD34 expression) and tumour hypoxia (carbonic anhydrase IX expression) did not correlate with (18)F-FDG PET parameters. In conclusion, repeatability of SUV(mean) and SUV(max) was mainly affected by preceding systemic therapy. The repeatability of tumour volume and TLG could be improved using more advanced and robust delineation approaches such as FLAB, which is recommended when (18)F-FDG PET is utilized for volume or TLG measurements. Improvement of repeatability of PET measurements, for instance by dynamic PET scanning protocols, is probably necessary to effectively use PET for early response monitoring.

Main predictors for repetition of suicidal behaviour among women referred to a single public sector tertiary care hospital in Iran.

PubMed

Mostafazadeh, Babak; Farzaneh, Esmaeil

2017-09-01

To assess the main predictors for repetition of suicidal behaviour among women. This cross-sectional study was conducted at Loghman Hakim Hospital, Tehran, Iran, in 2014, and comprised women patients. The patients were divided into two groups, i.e. women repeating suicide and women without repeating suicide. Data was collected through a checklist and then analysed with SPSS 20. Of the 300 women, 121(40.3%) repeated suicide and 179(59.7%) did not. The overall mean age was 26.9±9.1 years (range: 14-80 years). High prevalence of psychological drug usage, alcohol use, history of self-mutilation (self-harm), psychotic disturbances, sexual relationships, as well as smoking and opium addition was revealed as major factors in repeated suicidal behaviour in women when compared with other women. The result of multivariate logistic regression model showed two factors of self-mutilation (odds ratio =2.692, p=0.002) and underlying psychotic disorders (odds ratio = 2.780, p<0.001) as main predictors of suicide in women. In this regard, demographic characteristics could not predict repeating suicidal attempts (p>0.05). The presence of underlying psychotic disorders and self-mutilation were main predictors for repetition of suicidal behaviour.

Membrane cofactor protein (CD46) is a keratinocyte receptor for the M protein of the group A streptococcus.

PubMed

Okada, N; Liszewski, M K; Atkinson, J P; Caparon, M

1995-03-28

The pathogenic Gram-positive bacterium Streptococcus pyogenes (group A streptococcus) is the causative agent of numerous suppurative diseases of human skin. The M protein of S. pyogenes mediates the adherence of the bacterium to keratinocytes, the most numerous cell type in the epidermis. In this study, we have constructed and analyzed a series of mutant M proteins and have shown that the C repeat domain of the M molecule is responsible for cell recognition. The binding of factor H, a serum regulator of complement activation, to the C repeat region of M protein blocked bacterial adherence. Factor H is a member of a large family of complement regulatory proteins that share a homologous structural motif termed the short consensus repeat. Membrane cofactor protein (MCP), or CD46, is a short consensus repeat-containing protein found on the surface of keratinocytes, and purified MCP could competitively inhibit the adherence of S. pyogenes to these cells. Furthermore, the M protein was found to bind directly to MCP, whereas mutant M proteins that lacked the C repeat domain did not bind MCP, suggesting that recognition of MCP plays an important role in the ability of the streptococcus to adhere to keratinocytes.

Glutamate quantification by PRESS or MEGA-PRESS: Validation, repeatability, and concordance.

PubMed

van Veenendaal, Tamar M; Backes, Walter H; van Bussel, Frank C G; Edden, Richard A E; Puts, Nicolaas A J; Aldenkamp, Albert P; Jansen, Jacobus F A

2018-05-01

While PRESS is often employed to measure glutamate concentrations, MEGA-PRESS enables simultaneous Glx (glutamate and glutamine) and GABA measurements. This study aimed to compare validation, repeatability, and concordance of different approaches for glutamate quantification at 3T to aid future studies in their selection of the appropriate sequence and quantification method. Nine phantoms with different glutamate and glutamine concentrations and five healthy participants were scanned twice to assess respectively the validation and repeatability of measurements with PRESS and MEGA-PRESS. To assess concordance between the different methods, results from 95 human participants were compared. PRESS, MEGA-PRESS (i.e. difference), and the MEGA-PRESS OFF spectra were analyzed with both LCModel and Gannet. In vitro, excellent agreement was shown between actual and measured glutamate concentrations for all measurements (r>0.98). In vivo CVs were better for PRESS (2.9%) than MEGA-PRESS (4.9%) and MEGA-PRESS OFF (4.2%). However, the concordance between the sequences was low (PRESS and MEGA-PRESS OFF, r=0.3) to modest (MEGA-PRESS versus MEGA-PRESS OFF, r=0.8). Both PRESS and MEGA-PRESS can be employed to measure in vivo glutamate concentrations, although PRESS shows a better repeatability. Comparisons between in vivo glutamate measures of different sequences however need to be interpreted cautiously. Copyright © 2018 Elsevier Inc. All rights reserved.

Environmental risk factors for dementia: a systematic review.

PubMed

Killin, Lewis O J; Starr, John M; Shiue, Ivy J; Russ, Tom C

2016-10-12

Dementia risk reduction is a major and growing public health priority. While certain modifiable risk factors for dementia have been identified, there remains a substantial proportion of unexplained risk. There is evidence that environmental risk factors may explain some of this risk. Thus, we present the first comprehensive systematic review of environmental risk factors for dementia. We searched the PubMed and Web of Science databases from their inception to January 2016, bibliographies of review articles, and articles related to publically available environmental data. Articles were included if they examined the association between an environmental risk factor and dementia. Studies with another outcome (for example, cognition), a physiological measure of the exposure, case studies, animal studies, and studies of nutrition were excluded. Data were extracted from individual studies which were, in turn, appraised for methodological quality. The strength and consistency of the overall evidence for each risk factor identified was assessed. We screened 4784 studies and included 60 in the review. Risk factors were considered in six categories: air quality, toxic heavy metals, other metals, other trace elements, occupational-related exposures, and miscellaneous environmental factors. Few studies took a life course approach. There is at least moderate evidence implicating the following risk factors: air pollution; aluminium; silicon; selenium; pesticides; vitamin D deficiency; and electric and magnetic fields. Studies varied widely in size and quality and therefore we must be circumspect in our conclusions. Nevertheless, this extensive review suggests that future research could focus on a short list of environmental risk factors for dementia. Furthermore, further robust, longitudinal studies with repeated measures of environmental exposures are required to confirm these associations.

Muscle deoxygenation and neural drive to the muscle during repeated sprint cycling.

PubMed

Racinais, Sébastien; Bishop, David; Denis, Romain; Lattier, Grégory; Mendez-Villaneuva, Alberto; Perrey, Stéphane

2007-02-01

To investigate muscle deoxygenation and neural drive-related changes during repeated cycling sprints in a fatiguing context. Nine healthy male subjects performed a repeated-sprint test (consisting of 10 x 6-s maximal sprints interspaced by 30 s of recovery). Oxygen uptake was measured breath-by-breath; muscle deoxygenation of the vastus lateralis was assessed continuously using the near-infrared spectroscopy technique. Surface electromyograms (RMS) of both vastus lateralis and biceps femoris were also recorded. Furthermore, before and after the repeated-sprint test, the percentage of muscle activation by voluntary drive (twitch-interpolated method) was measured during a maximal voluntary contraction. Consistent with previous research, our data showed a significant power decrement during repeated-sprint exercise. There was also a progressive muscle deoxygenation, but our data showed that the ability of the subjects to use available O2 throughout the entire repeated-sprint test was well preserved. Our data displayed a significant decrement in the RMS activity during the acceleration phase of each sprint across the repeated-sprint exercise. Moreover, decrement in motor drive was confirmed after exercise by a significant decrease in both percentage of voluntary activation and RMS/M-wave ratio during a maximal voluntary contraction. In this experimental design, our findings suggest that the ability to repeat short-duration (6 s) sprints was associated with the occurrence of both peripheral and central fatigue.

Association of genetic variants of MAOA and SH2B1 with bone mineral density in community-dwelling Japanese women.

PubMed

Yamada, Yoshiji; Ando, Fujiko; Shimokata, Hiroshi

2008-01-01

Although bone mineral density (BMD) is a complex trait that is influenced by both genetic and environmental factors, heritability studies in twins and families have shown that genetic factors account for 60-85% of its variance. We examined the relation of the variable number of tandem repeats (VNTR) polymorphism of the monoamine oxidase A gene (MAOA) and the A↷G (Thr484Ala) polymorphism of the SH2B adaptor protein 1 gene (SH2B1) to BMD in community-dwelling Japanese women and men. The 2235 subjects (1107 women, 1128 men) were aged 40-79 years and were randomly recruited for a population-based prospective cohort study of aging and age-related diseases in Japan. BMD at the distal and proximal radius was measured by peripheral quantitative computed tomography, and the BMD of the total body, lumbar spine (L2-L4), right femoral neck and right trochanter was measured by dual-energy X-ray absorptiometry. The genotypes of the VNTR polymorphism of MAOA were determined by DNA fragment analysis, and those of the A↷G (Thr484Ala) polymorphism of SH2B1 by melting curve analysis. The VNTR polymorphism of MAOA was associated with the BMD of the distal radius, total body, lumbar spine and trochanter in all women, and with the BMD of the total body and trochanter in postmenopausal ones, with the L (four repeats) and S (two or three repeats) alleles reflecting increased and decreased BMD, respectively. The A↷G (Thr484Ala) polymorphism of SH2B1 was associated with the BMD of the lumbar spine in all women, with the BMD of the proximal radius in premenopausal women and with the BMD of the lumbar spine, femoral neck and trochanter in postmenopausal women, with the variant G allele being related to increased BMD. These results suggest that MAOA and SH2B1 are determinative loci for bone mass in Japanese women, especially in postmenopausal ones.

Repeatability of a new method for measuring tear evaporation rates.

PubMed

Petznick, Andrea; Tan, Jen Hong; Boo, Shiao Khee; Lee, Sze Yee; Acharya, U Rajendra; Tong, Louis

2013-04-01

The purpose of this study was to evaluate the repeatability of tear evaporimetry based on infrared thermography in a clinical room setting and to test the effect of changing environmental humidity on ocular surface temperature (OST) and tear evaporation rates (TERs) in a controlled adverse environmental (CAE) chamber. Twenty-six healthy participants were enrolled, of whom 16 underwent repeatability measurements in a clinical room and 10 were exposed to a constant temperature of 30°C with a humidity of 45 and 65% in a CAE. Participants were acclimatized to each condition for at least 20 minutes before OSTs were taken. Tear film breakup time was assessed in the CAE only. Number of blinks and OSTs were continuously measured for 20 seconds for the cornea, conjunctiva, and overall ocular surface with an infrared camera; corresponding TERs were calculated. The OSTs and TERs showed acceptable strength of agreement between the first and second measurements. The coefficients of repeatability were 0.4°C for OST and 6.0 W m for TER. An increase in chamber humidity (from 45 to 65%) increased OST (p < 0.05). The TER was not changed significantly (p > 0.05). The tear film breakup time and number of blinks were not significantly affected by different humidity conditions. This technique has acceptable repeatability and has potential to document individual tear evaporation changes with time where humidity may differ by less than 20%.

Repeat Offending and Repeat Victimization: Assessing Similarities and Differences in Psychosocial Risk Factors

ERIC Educational Resources Information Center

Fagan, Abigail A.; Mazerolle, Paul

2011-01-01

The overlap between victims and offenders is increasingly being recognized, with mounting evidence that victims and offenders have similar demographic characteristics, that victimization increases the likelihood of offending, and that offenders are at high risk for becoming victims of crime. Despite this evidence, there is limited research…

Exploring Proficiency-Based vs. Performance-Based Items with Elicited Imitation Assessment

ERIC Educational Resources Information Center

Cox, Troy L.; Bown, Jennifer; Burdis, Jacob

2015-01-01

This study investigates the effect of proficiency- vs. performance-based elicited imitation (EI) assessment. EI requires test-takers to repeat sentences in the target language. The accuracy at which test-takers are able to repeat sentences highly correlates with test-takers' language proficiency. However, in EI, the factors that render an item…

Rare Plants of the Redwood Forest and Forest Management Effects

Treesearch

Teresa Sholars; Clare Golec

2007-01-01

Coast redwood forests are predominantly a timber managed habitat type, subjected to repeated disturbances and short rotation periods. What does this repeated disturbance mean for rare plants associated with the redwood forests? Rare plant persistence through forest management activities is influenced by many factors. Persistence of rare plants in a managed landscape is...

EFFECTS OF DIFFERENT WARM-UP PROGRAMS ON GOLF PERFORMANCE IN ELITE MALE GOLFERS

PubMed Central

Macfarlane, Alison

2012-01-01

Background: The physical demands required of the body to execute a shot in golf are enormous. Current evidence suggests that warm-up involving static stretching is detrimental to immediate performance in golf as opposed to active dynamic stretching. However the effect of resistance exercises during warm-up before golf on immediate performance is unknown. Therefore, the purpose of this study was to assess the effects of three different warm-up programs on immediate golf performance. Methods: Fifteen elite male golfers completed three different warm-up programs over three sessions on non-consecutive days. After each warm-up program each participant hit ten maximal drives with the ball flight and swing analyzed with Flightscope® to record maximum club head speed (MCHS), maximal driving distance (MDD), driving accuracy (DA), smash factor (SF) and consistent ball strike (CBS). Results: Repeated measures ANOVA tests showed statistically significant difference within 3 of the 5 factors of performance (MDD, CBS and SF). Subsequently, a paired t-test then showed statistically significant (p<0.05) improvements occurred in each of these three factors in the group performing a combined active dynamic and functional resistance (FR) warm-up as opposed to either the active dynamic (AD) warm-up or the combined AD with weights warm-up (WT). There were no statistically significant differences observed between the AD warm-up and the WT warm-up for any of the five performance factors and no statistical significant difference between any of the warm-ups for maximum clubhead speed (MCHS) and driving accuracy (DA). Conclusion: Performing a combined AD and FR warm up with Theraband® leads to significant increase in immediate performance of certain factors of the golf drive compared to performing an AD warm-up by itself or a combined AD with WT warm-up. No significant difference was observed between the three warm-up groups when looking at immediate effect on driving accuracy or maximum club head speed. The addition of functional resistance activities to active dynamic stretching has immediate benefits to elite male golfers in relation to some factors of their performance. Level of Evidence: This study is a Quantitative Experimental design using repeated measures and multiple crossovers. It cannot be classified using the descriptive level of evidence. PMID:23936749

Repeatability of Bolus Kinetics Ultrasound Perfusion Imaging for the Quantification of Cerebral Blood Flow.

PubMed

Vinke, Elisabeth J; Eyding, Jens; de Korte, Chris L; Slump, Cornelis H; van der Hoeven, Johannes G; Hoedemaekers, Cornelia W E

2017-12-01

Ultrasound perfusion imaging (UPI) can be used for the quantification of cerebral perfusion. In a neuro-intensive care setting, repeated measurements are required to evaluate changes in cerebral perfusion and monitor therapy. The aim of this study was to determine the repeatability of UPI in quantification of cerebral perfusion. UPI measurement of cerebral perfusion was performed three times in healthy patients. The coefficients of variation of the three bolus injections were calculated for both time- and volume-derived perfusion parameters in the macro- and microcirculation. The UPI time-dependent parameters had overall the lowest CVs in both the macro- and microcirculation. The volume-related parameters had poorer repeatability, especially in the microcirculation. Both intra-observer variability and inter-observer variability were low. Although UPI is a promising tool for the bedside measurement of cerebral perfusion, improvement of the technique is required before implementation in routine clinical practice. Copyright © 2017 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

The Influence of Non-Nociceptive Factors on Hot Plate Latency in Rats

PubMed Central

Gunn, Amanda; Bobeck, Erin N.; Weber, Ceri; Morgan, Michael M.

2010-01-01

The hot plate is a widely used test to assess nociception. The effect of non-nociceptive factors (weight, sex, activity, habituation, and repeated testing) on hot plate latency was examined. Comparison of body weight and hot plate latency revealed a small but significant inverse correlation (light rats had longer latencies). Habituating rats to the test room for 1 hr prior to testing did not decrease hot plate latency except for female rats tested on Days 2 - 4. Hot plate latency decreased with repeated daily testing, but this was not caused by a decrease in locomotor activity or learning to respond. Activity on the hot plate was consistent across all four trials, and prior exposure to a room temperature plate caused a similar decrease in latency as rats tested repeatedly on the hot plate. Despite this decrease in baseline hot plate latency, there was no difference in morphine antinociceptive potency. The present study shows that weight, habituation to the test room, and repeated testing can alter baseline hot plate latency, but these effects are small and have relatively little impact on morphine antinociception. PMID:20797920

A novel method for repeatedly generating speckle patterns used in digital image correlation

NASA Astrophysics Data System (ADS)

Zhang, Juan; Sweedy, Ahmed; Gitzhofer, François; Baroud, Gamal

2018-01-01

Speckle patterns play a key role in Digital Image Correlation (DIC) measurement, and generating an optimal speckle pattern has been the goal for decades now. The usual method of generating a speckle pattern is by manually spraying the paint on the specimen. However, this makes it difficult to reproduce the optimal pattern for maintaining identical testing conditions and achieving consistent DIC results. This study proposed and evaluated a novel method using an atomization system to repeatedly generate speckle patterns. To verify the repeatability of the speckle patterns generated by this system, simulation and experimental studies were systematically performed. The results from both studies showed that the speckle patterns and, accordingly, the DIC measurements become highly accurate and repeatable using the proposed atomization system.

Age-related invariance of abilities measured with the Wechsler Adult Intelligence Scale-IV.

PubMed

Sudarshan, Navaneetham J; Bowden, Stephen C; Saklofske, Donald H; Weiss, Lawrence G

2016-11-01

Assessment of measurement invariance across populations is essential for meaningful comparison of test scores, and is especially relevant where repeated measurements are required for educational assessment or clinical diagnosis. Establishing measurement invariance legitimizes the assumption that test scores reflect the same psychological trait in different populations or across different occasions. Examination of Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) U.S. standardization samples revealed that a first-order 5-factor measurement model was best fitting across 9 age groups from 16 years to 69 years. Strong metric invariance was found for 3 of 5 factors and partial intercept invariance for the remaining 2. Pairwise comparisons of adjacent age groups supported the inference that cognitive-trait group differences are manifested by group differences in the test scores. In educational and clinical settings these findings provide theoretical and empirical support to interpret changes in the index or subtest scores as reflecting changes in the corresponding cognitive abilities. Further, where clinically relevant, the subtest score composites can be used to compare changes in respective cognitive abilities. The model was supported in the Canadian standardization data with pooled age groups but the sample sizes were not adequate for detailed examination of separate age groups in the Canadian sample. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Slide-and-exchange mechanism for rapid and selective transport through the nuclear pore complex.

PubMed

Raveh, Barak; Karp, Jerome M; Sparks, Samuel; Dutta, Kaushik; Rout, Michael P; Sali, Andrej; Cowburn, David

2016-05-03

Nucleocytoplasmic transport is mediated by the interaction of transport factors (TFs) with disordered phenylalanine-glycine (FG) repeats that fill the central channel of the nuclear pore complex (NPC). However, the mechanism by which TFs rapidly diffuse through multiple FG repeats without compromising NPC selectivity is not yet fully understood. In this study, we build on our recent NMR investigations showing that FG repeats are highly dynamic, flexible, and rapidly exchanging among TF interaction sites. We use unbiased long timescale all-atom simulations on the Anton supercomputer, combined with extensive enhanced sampling simulations and NMR experiments, to characterize the thermodynamic and kinetic properties of FG repeats and their interaction with a model transport factor. Both the simulations and experimental data indicate that FG repeats are highly dynamic random coils, lack intrachain interactions, and exhibit significant entropically driven resistance to spatial confinement. We show that the FG motifs reversibly slide in and out of multiple TF interaction sites, transitioning rapidly between a strongly interacting state and a weakly interacting state, rather than undergoing a much slower transition between strongly interacting and completely noninteracting (unbound) states. In the weakly interacting state, FG motifs can be more easily displaced by other competing FG motifs, providing a simple mechanism for rapid exchange of TF/FG motif contacts during transport. This slide-and-exchange mechanism highlights the direct role of the disorder within FG repeats in nucleocytoplasmic transport, and resolves the apparent conflict between the selectivity and speed of transport.

Engineering customized TALE nucleases (TALENs) and TALE transcription factors by fast ligation-based automatable solid-phase high-throughput (FLASH) assembly.

PubMed

Reyon, Deepak; Maeder, Morgan L; Khayter, Cyd; Tsai, Shengdar Q; Foley, Jonathan E; Sander, Jeffry D; Joung, J Keith

2013-07-01

Customized DNA-binding domains made using transcription activator-like effector (TALE) repeats are rapidly growing in importance as widely applicable research tools. TALE nucleases (TALENs), composed of an engineered array of TALE repeats fused to the FokI nuclease domain, have been used successfully for directed genome editing in various organisms and cell types. TALE transcription factors (TALE-TFs), consisting of engineered TALE repeat arrays linked to a transcriptional regulatory domain, have been used to up- or downregulate expression of endogenous genes in human cells and plants. This unit describes a detailed protocol for the recently described fast ligation-based automatable solid-phase high-throughput (FLASH) assembly method. FLASH enables automated high-throughput construction of engineered TALE repeats using an automated liquid handling robot or manually using a multichannel pipet. Using the automated approach, a single researcher can construct up to 96 DNA fragments encoding TALE repeat arrays of various lengths in a single day, and then clone these to construct sequence-verified TALEN or TALE-TF expression plasmids in a week or less. Plasmids required for FLASH are available by request from the Joung lab (http://eGenome.org). This unit also describes improvements to the Zinc Finger and TALE Targeter (ZiFiT Targeter) web server (http://ZiFiT.partners.org) that facilitate the design and construction of FLASH TALE repeat arrays in high throughput. © 2013 by John Wiley & Sons, Inc.

Engineering Customized TALE Nucleases (TALENs) and TALE Transcription Factors by Fast Ligation-based Automatable Solid-phase High-throughput (FLASH) Assembly

PubMed Central

Reyon, Deepak; Maeder, Morgan L.; Khayter, Cyd; Tsai, Shengdar Q.; Foley, Jonathan E.; Sander, Jeffry D.; Joung, J. Keith

2013-01-01

Customized DNA-binding domains made using Transcription Activator-Like Effector (TALE) repeats are rapidly growing in importance as widely applicable research tools. TALE nucleases (TALENs), composed of an engineered array of TALE repeats fused to the FokI nuclease domain, have been used successfully for directed genome editing in multiple different organisms and cell types. TALE transcription factors (TALE-TFs), consisting of engineered TALE repeat arrays linked to a transcriptional regulatory domain, have been used to up- or down-regulate expression of endogenous genes in human cells and plants. Here we describe a detailed protocol for practicing the recently described Fast Ligation-based Automatable Solid-phase High-throughput (FLASH) assembly method. FLASH enables automated high-throughput construction of engineered TALE repeats using an automated liquid handling robot or manually using a multi-channel pipet. With the automated version of FLASH, a single researcher can construct up to 96 DNA fragments encoding various length TALE repeat arrays in one day and then clone these to construct sequence-verified TALEN or TALE-TF expression plasmids in one week or less. Plas-mids required to practice FLASH are available by request from the Joung Lab (http://www.jounglab.org/). We also describe here improvements to the Zinc Finger and TALE Targeter (ZiFiT Targeter) webserver (http://ZiFiTBeta.partners.org) that facilitate the design and construction of FLASH TALE repeat arrays in high-throughput. PMID:23821439

An Empirical Comparison of Competing Factor Structures for the Repeatable Battery for the Assessment of Neuropsychological Status: A Project FRONTIER Study†

PubMed Central

Torrence, Nicole D.; John, Samantha E.; Gavett, Brandon E.; O'Bryant, Sid E.

2016-01-01

The original factor structure of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has received little empirical support, but at least eight alternative factor structures have been identified in the literature. The current study used confirmatory factor analysis to compare the original RBANS model with eight alternatives, which were adjusted to include a general factor. Participant data were obtained from Project FRONTIER, an epidemiological study of rural health, and comprised 341 adults (229 women, 112 men) with mean age of 61.2 years (SD = 12.1) and mean education of 12.4 years (SD = 3.3). A bifactor version of the model proposed by Duff and colleagues provided the best fit to the data (CFI = 0.98; root-mean-squared error of approximation = 0.07), but required further modification to produce appropriate factor loadings. The results support the inclusion of a general factor and provide partial replication of the Duff and colleagues RBANS model. PMID:26429558

Validation of OCT-based Crystalline Lens Thickness Measurements in Children

PubMed Central

Lehman, Bret M.; Berntsen, David A.; Bailey, Melissa D.; Zadnik, Karla

2010-01-01

Purpose To evaluate the validity and repeatability of crystalline lens thickness measurements obtained by anterior segment optical coherence tomography. Methods Forty-seven normal children (mean age, 11.06 ± 2.30 years) had their crystalline lens thickness measured with the Visante anterior segment optical coherence tomography (OCT) (Carl Zeiss Meditec, Dublin, CA) and with conventional corneal touch A-scan ultransonography (ultrasound) (Humphrey 820). The subjects’ right corneas were anesthetized, and their right eyes were cyclopleged. Five ultrasound measurements were recorded per eye, and three Visante OCT measurements were recorded per eye. Thirty-eight subjects had measurements at a second visit where three additional Visante OCT measurements were recorded. Results The mean of the differences between the Visante OCT and ultrasound was −0.045 mm (p = 0.017) with 95% limits of agreement from −0.29 to 0.20 mm indicating that the measurement of crystalline lens thickness was slightly thinner with the Visante OCT. When validity was assessed using only Visante OCT images that contained the corneal reflex, the mean of the differences was 0.019 mm (p = 0.11) with 95% limits of agreement from −0.091 to 0.13 mm. For the repeatability of the Visante OCT, the mean of the differences between visit one and visit two was −0.008 mm (p = 0.25) with 95% limits of agreement from −0.088 to 0.072 mm. Repeatability improved when reassessed using only images that contain the corneal reflex; the mean of the differences was −0.0001 mm (p = 0.97) with 95% limits of agreement from −0.030 to 0.030 mm. Conclusion The Visante OCT is a non-contact instrument that is simple to use, and it provides valid crystalline lens thickness measurements with excellent repeatability. Validity and repeatability are optimized when the Visante OCT images contain the corneal reflex and a consistent corneal index refraction is applied to the entire image. PMID:19182701

Effects of Covariance Heterogeneity on Three Procedures for Analyzing Multivariate Repeated Measures Designs.

ERIC Educational Resources Information Center

Vallejo, Guillermo; Fidalgo, Angel; Fernandez, Paula

2001-01-01

Estimated empirical Type I error rate and power rate for three procedures for analyzing multivariate repeated measures designs: (1) the doubly multivariate model; (2) the Welch-James multivariate solution (H. Keselman, M. Carriere, a nd L. Lix, 1993); and (3) the multivariate version of the modified Brown-Forsythe procedure (M. Brown and A.…

Pairwise Multiple Comparisons in Single Group Repeated Measures Analysis.

ERIC Educational Resources Information Center

Barcikowski, Robert S.; Elliott, Ronald S.

Research was conducted to provide educational researchers with a choice of pairwise multiple comparison procedures (P-MCPs) to use with single group repeated measures designs. The following were studied through two Monte Carlo (MC) simulations: (1) The T procedure of J. W. Tukey (1953); (2) a modification of Tukey's T (G. Keppel, 1973); (3) the…

Hospital Presenting Self-Harm and Risk of Fatal and Non-Fatal Repetition: Systematic Review and Meta-Analysis

PubMed Central

Carroll, Robert; Metcalfe, Chris; Gunnell, David

2014-01-01

Background Non-fatal self-harm is one of the most frequent reasons for emergency hospital admission and the strongest risk factor for subsequent suicide. Repeat self-harm and suicide are key clinical outcomes of the hospital management of self-harm. We have undertaken a comprehensive review of the international literature on the incidence of fatal and non-fatal repeat self-harm and investigated factors influencing variation in these estimates as well as changes in the incidence of repeat self-harm and suicide over the last 30 years. Methods and Findings Medline, EMBASE, PsycINFO, Google Scholar, article reference lists and personal paper collections of the authors were searched for studies describing rates of fatal and non-fatal self-harm amongst people who presented to health care services for deliberate self-harm. Heterogeneity in pooled estimates of repeat self-harm incidence was investigated using stratified meta-analysis and meta-regression. The search identified 177 relevant papers. The risk of suicide in the 12 months after an index attempt was 1.6% (CI 1.2–2.4) and 3.9% (CI 3.2–4.8) after 5 years. The estimated 1 year rate of non-fatal repeat self-harm was 16.3% (CI 15.1–17.7). This proportion was considerably lower in Asian countries (10.0%, CI 7.3–13.6%) and varies between studies identifying repeat episodes using hospital admission data (13.7%, CI 12.3–15.3) and studies using patient report (21.9%, CI 14.3–32.2). There was no evidence that the incidence of repeat self-harm was lower in more recent (post 2000) studies compared to those from the 1980s and 1990s. Conclusions One in 25 patients presenting to hospital for self-harm will kill themselves in the next 5 years. The incidence of repeat self-harm and suicide in this population has not changed in over 10 years. Different methods of identifying repeat episodes of self-harm produce varying estimates of incidence and this heterogeneity should be considered when evaluating interventions aimed at reducing non-fatal repeat self-harm. PMID:24587141

GREAM: A Web Server to Short-List Potentially Important Genomic Repeat Elements Based on Over-/Under-Representation in Specific Chromosomal Locations, Such as the Gene Neighborhoods, within or across 17 Mammalian Species

PubMed Central

Chandrashekar, Darshan Shimoga; Dey, Poulami; Acharya, Kshitish K.

2015-01-01

Background Genome-wide repeat sequences, such as LINEs, SINEs and LTRs share a considerable part of the mammalian nuclear genomes. These repeat elements seem to be important for multiple functions including the regulation of transcription initiation, alternative splicing and DNA methylation. But it is not possible to study all repeats and, hence, it would help to short-list before exploring their potential functional significance via experimental studies and/or detailed in silico analyses. Result We developed the ‘Genomic Repeat Element Analyzer for Mammals’ (GREAM) for analysis, screening and selection of potentially important mammalian genomic repeats. This web-server offers many novel utilities. For example, this is the only tool that can reveal a categorized list of specific types of transposons, retro-transposons and other genome-wide repetitive elements that are statistically over-/under-represented in regions around a set of genes, such as those expressed differentially in a disease condition. The output displays the position and frequency of identified elements within the specified regions. In addition, GREAM offers two other types of analyses of genomic repeat sequences: a) enrichment within chromosomal region(s) of interest, and b) comparative distribution across the neighborhood of orthologous genes. GREAM successfully short-listed a repeat element (MER20) known to contain functional motifs. In other case studies, we could use GREAM to short-list repetitive elements in the azoospermia factor a (AZFa) region of the human Y chromosome and those around the genes associated with rat liver injury. GREAM could also identify five over-represented repeats around some of the human and mouse transcription factor coding genes that had conserved expression patterns across the two species. Conclusion GREAM has been developed to provide an impetus to research on the role of repetitive sequences in mammalian genomes by offering easy selection of more interesting repeats in various contexts/regions. GREAM is freely available at http://resource.ibab.ac.in/GREAM/. PMID:26208093

Repeated vertebral augmentation for new vertebral compression fractures of postvertebral augmentation patients: a nationwide cohort study

PubMed Central

Liang, Cheng-Loong; Wang, Hao-Kwan; Syu, Fei-Kai; Wang, Kuo-Wei; Lu, Kang; Liliang, Po-Chou

2015-01-01

Purpose Postvertebral augmentation vertebral compression fractures are common; repeated vertebral augmentation is usually performed for prompt pain relief. This study aimed to evaluate the incidence and risk factors of repeat vertebral augmentation. Methods We performed a retrospective, nationwide, population-based longitudinal observation study, using the National Health Insurance Research Database (NHIRD) of Taiwan. All patients who received vertebral augmentation for vertebral compression fractures were evaluated. The collected data included patient characteristics (demographics, comorbidities, and medication exposure) and repeat vertebral augmentation. Kaplan–Meier and stratified Cox proportional hazard regressions were performed for analyses. Results The overall incidence of repeat vertebral augmentation was 11.3% during the follow-up until 2010. Patients with the following characteristics were at greater risk for repeat vertebral augmentation: female sex (AOR=1.24; 95% confidence interval [CI]: 1.10–2.36), advanced age (AOR=1.60; 95% CI: 1.32–2.08), diabetes mellitus (AOR=4.31; 95% CI: 4.05–5.88), cerebrovascular disease (AOR=4.09; 95% CI: 3.44–5.76), dementia (AOR=1.97; 95% CI: 1.69–2.33), blindness or low vision (AOR=3.72; 95% CI: 2.32–3.95), hypertension (AOR=2.58; 95% CI: 2.35–3.47), and hyperlipidemia (AOR=2.09; 95% CI: 1.67–2.22). Patients taking calcium/vitamin D (AOR=2.98; 95% CI: 1.83–3.93), bisphosphonates (AOR=2.11; 95% CI: 1.26–2.61), or calcitonin (AOR=4.59; 95% CI: 3.40–5.77) were less likely to undergo repeat vertebral augmentation; however, those taking steroids (AOR=7.28; 95% CI: 6.32–8.08), acetaminophen (AOR=3.54; 95% CI: 2.75–4.83), or nonsteroidal anti-inflammatory drugs (NSAIDs) (AOR=6.14; 95% CI: 5.08–7.41) were more likely to undergo repeat vertebral augmentation. Conclusion We conclude that the incidence of repeat vertebral augmentation is rather high. An understanding of risk factors predicting repeat vertebral augmentation provides valuable basis to improve health care for geriatric populations. PMID:25848240

[Effects of mere exposure on category evaluation measured by the IAT and the GNAT].

PubMed

Kawakami, Naoaki; Sato, Hirotsune; Yoshida, Fujio

2010-12-01

Based on mere exposure studies, we proposed that repeated exposure to stimuli belonging to a common category leads to a positive evaluation of that category. Furthermore, to investigate the implicit effects of mere exposure, indirect measures were used. In a series of experiments, participants were repeatedly exposed to mimetic words written in Japanese hiragana or katakana, or nothing (control). Then their evaluations of the category ("hiragana" or "katakana") were measured using indirect and direct measures. In Experiment 1 (Implicit Association Test; IAT), we adopted a traditional design using an exposure paradigm, such that the rating stimuli were identical to the exposed stimuli. Significant effects were observed for both measures. In Experiment 2 (IAT) and Experiment 3 (Go/No-go Association Task; GNAT), we used non-exposed stimuli that belonged to a common category as the rating stimuli. Significant effects were observed only for indirect measures. These results indicate that repeated exposure has unconscious positive effects on category evaluation. Theoretical and methodological implications of the findings are discussed.

A method of measuring anterior chamber volume using the anterior segment optical coherence tomographer and specialized software.

PubMed

Wang, Ningli; Wang, Bingsong; Zhai, Gaoshou; Lei, Kun; Wang, Lan; Congdon, Nathan

2007-05-01

To describe and evaluate a new method for measuring anterior chamber volume (ACV). Observational case series. The authors measured ACV using the anterior chamber (AC) optical coherence tomographer (OCT) and applied image-processing software developed by them. Repeatability was evaluated. The ACV was measured in patient groups with normal ACs, shallow ACs, and deep ACs. The volume difference before and after laser peripheral iridotomy (LPI) was analyzed for the shallow and deep groups. Coefficients of repeatability for intraoperator, interoperator, and interimage measurements were 0.406%, 0.958%, and 0.851%, respectively. The limits of agreement for intraoperator and interoperator measurement were -0.911 microl to 1.343 microl and -7.875 microl to -2.463 microl, respectively. There were significant ACV differences in normal, shallow, and deep AC eyes (P < .001) and before and after LPI in shallow AC (P < .001) and deep AC (P = .008) eyes. The ACV values obtained by this method were repeatable and in accord with clinical observation.

ACUTE AND REPEATED INHALATION OF TOLUENE BY RATS PERFORMING A SIGNAL DETECTION TASK LEADS TO BEHAVIORAL TOLERANCE ON SOME PERFORMANCE MEASURES.

EPA Science Inventory

Previous work showed that trichloroethylene (TCE) impairs accuracy and latency in a signal detection task (SDT) in rats, and that these effects abate during repeated exposures if rats inhale TCE during SDT testing. The present experiment compared the effects of acute and repeated...

Macrophage migration inhibitory factor polymorphisms do not predict therapeutic response to glucocorticoids or to tumour necrosis factor alpha-neutralising treatments in rheumatoid arthritis.

PubMed

Radstake, Timothy R D J; Fransen, Jaap; Toonen, Erik J M; Coenen, Marieke J H; Eijsbouts, Agnes E; Donn, Rachelle; van den Hoogen, Frank H J; van Riel, Piet L C M

2007-11-01

Macrophage migration inhibitory factor (MIF) is an inflammatory mediator associated with RA severity. In various diseases, MIF polymorphisms are associated with clinical response glucocorticoid (GC) treatment. It is unclear whether MIF polymorphisms determine GC response in rheumatoid arthritis (RA) and to other RA treatments. Therefore, the question of whether two functional variants in MIF are associated with the response to tumour necrosis factor (TNF)alpha-neutralising and GC treatments in RA was investigated. Data from two cohorts of an RA registry were used. For patients who started with TNFalpha-neutralising (infliximab) or GC treatment, courses with a duration of at least 3 months were included and response to TNFalpha blockers or GC was calculated according to the European League Against Rheumatism response criteria. MIF -173G-->C genotyping was achieved using an assay-on-demand allelic discrimination assay, and alleles of the CATT repeat element were identified using a fluorescently labelled PCR primer and capillary electrophoresis. Logistic-regression modelling was used for the statistical analysis. In total, 192 courses of oral prednisone or methylprednisolone injections in 98 patients with RA and 90 patients with RA who were on TNFalpha-neutralising treatments were documented. In all, 27% of the patients with RA were found to be heterozygous for seven CATT repeats (CATT(7)) and 31% were heterozygous for -173C. Respectively, 4% and 6% of the patients with RA were homozygous for the MIF CATT(7) repeat or the MIF -173C allele. Carrier status and homozygosity for CATT(7 )repeat and the MIF -173C allele were not associated with response to GC (odds ratios (ORs) close to 1) or to TNFalpha-neutralising treatment (ORs close to 2). The MIF-CATT(7) repeat and the MIF-173G-->C functional variant are not strongly associated with a decreased clinical response to TNFalpha-neutralising or GC treatment in RA.

Patient satisfaction with the endoscopy experience and willingness to return in a central Canadian health region.

PubMed

Loftus, Russell; Nugent, Zoann; Graff, Lesley A; Schumacher, Frederick; Bernstein, Charles N; Singh, Harminder

2013-01-01

Patient experiences with endoscopy visits within a large central Canadian health region were evaluated to determine the relationship between the visit experience and the patients' willingness to return for future endoscopy, and to identify the factors associated with patients' willingness to return. A self-report survey was distributed to 1200 consecutive individuals undergoing an upper and⁄or lower gastrointestinal endoscopy at any one of the six hospital-based endoscopy facilities in the region. The Spearman correlation coefficient was used to assess the association between the patients' overall rating of the visits and willingness to return for repeat procedures under similar medical circumstances. Logistic regression analyses were performed to identify the factors associated with willingness to return for repeat endoscopy and overall satisfaction (rating) of the visit. A total of 529 (44%) individuals returned the questionnaire, with 45% rating the visit as excellent and 56% indicating they were extremely likely to return for repeat endoscopy. There was a low moderate correlation between overall rating of the visit and patients' willingness to return for repeat endoscopy (r=0.30). The factors independently associated with patient willingness to return for repeat endoscopy included perceived technical skills of the endoscopists (OR 2.7 [95% CI 1.3 to 5.5]), absence of pain during the procedure (OR 2.2 [95% CI 1.3 to 3.6]) and history of previous endoscopy (OR 2.4 [95% CI 1.4 to 4.1]). In contrast, the independent factors associated with the overall rating of the visit included information provided pre- and postprocedure, wait time before and on the day of the visit, and the physical environment. To facilitate patient return for needed endoscopy, it is important to assess patients' willingness to return because positive behavioural intent is not simply a function of satisfaction with the visit.

Babesia bovis and Babesia bigemina infection levels estimated by qPCR in Angus cattle from an endemic area of São Paulo state, Brazil.

PubMed

Giglioti, R; Oliveira, H N; Santana, C H; Ibelli, A M G; Néo, T A; Bilhassi, T B; Rabelo, M D; Machado, R Z; Brito, L G; Oliveira, M C S

2016-07-01

The levels of infection by Babesia bovis and Babesia bigemina were estimated by absolute quantification through the quantitative PCR technique (qPCR). Fifty-one contemporaneous Angus cattle were evaluated on two occasions. The number of standard female Rhipicephalus microplus ticks present on the left side of the body was counted and blood samples were drawn from the tail vein into tubes containing the anticoagulant EDTA. The blood samples were submitted to DNA extraction and used to quantify the number of copies (NC) of DNA from B. bovis and B. bigemina by qPCR. The data on tick count and number of DNA copies were transformed for normalization and analyzed by a mixed model method. A multivariate model with repeated measures of the same animal, including the effects of collection, parasite species and their interaction, was used. The repeatability values were obtained from the matrix of (co)variances and were expressed for each species. The correlations between the counts of different species on the same animal, in the same collection or different collections, were also estimated. The results showed the qPCR could distinguish the two between infection by the two Babesia species. Infection levels by B. bovis and B. bigemina were detected in 100% and 98% of the animals, respectively. Significant differences were found (P<0.05) between the NC of the two Babesia species, B. bovis 1.49±0.07 vs. B. bigemina 0.82±0.06. Low repeatabilities were found for the counts of R. microplus and NC of B. bovis and B. bigemina: 0.05, 0.10 and 0.02, respectively. The correlations between R. microplus count and NC of B. bovis and B. bigemina were both very near zero. However, an association was observed between the NC of the two species, with a correlation coefficient of 0.30 for measures from the same collection. The absence of associations between the quantity of DNA from B. bovis and B. bigemina and the tick counts suggests that the variation of parasitemia by the hemoparasites did not depend on the tick infestation levels at the moment of each collection. The repeatability values estimated indicate that under the study conditions, the variations in the tick infestation levels and of parasitemia by B. bovis and B. bigemina depend more on factors related to each collection than on intrinsic factors of the animal. Copyright © 2016 Elsevier GmbH. All rights reserved.

Instability of expanded CAG/CAA repeats in spinocerebellar ataxia type 17.

PubMed

Gao, Rui; Matsuura, Tohru; Coolbaugh, Mary; Zühlke, Christine; Nakamura, Koichiro; Rasmussen, Astrid; Siciliano, Michael J; Ashizawa, Tetsuo; Lin, Xi

2008-02-01

Trinucleotide repeat expansions are dynamic mutations causing many neurological disorders, and their instability is influenced by multiple factors. Repeat configuration seems particularly important, and pure repeats are thought to be more unstable than interrupted repeats. But direct evidence is still lacking. Here, we presented strong support for this hypothesis from our studies on spinocerebellar ataxia type 17 (SCA17). SCA17 is a typical polyglutamine disease caused by CAG repeat expansion in TBP (TATA binding protein), and is unique in that the pure expanded polyglutamine tract is coded by either a simple configuration with long stretches of pure CAGs or a complex configuration containing CAA interruptions. By small pool PCR (SP-PCR) analysis of blood DNA from SCA17 patients of distinct racial backgrounds, we quantitatively assessed the instability of these two types of expanded alleles coding similar length of polyglutamine expansion. Mutation frequency in patients harboring pure CAG repeats is 2-3 folds of those with CAA interruptions. Interestingly, the pure CAG repeats showed both expansion and deletion while the interrupted repeats exhibited mostly deletion at a significantly lower frequency. These data strongly suggest that repeat configuration is a critical determinant for instability, and CAA interruptions might serve as a limiting element for further expansion of CAG repeats in SCA17 locus, suggesting a molecular basis for lack of anticipation in SCA17 families with interrupted CAG expansion.

Von Willebrand factor, a versatile player in gastrointestinal bleeding in left ventricular assist device recipients?

PubMed

Fischer, Quentin; Huisse, Marie-Geneviève; Voiriot, Guillaume; Caron, Claudine; Lepage, Laurent; Dilly, Marie-Pierre; Nataf, Patrick; Ajzenberg, Nadine; Kirsch, Matthias

2015-01-01

Bleeding originating in the gastrointestinal (GI) tract is one of the most common adverse events after left ventricular assist device (LVAD) implantation. In these patients, GI bleeding appears to be the consequence of altered hemostasis on the one hand and alterations of the GI microvasculature on the other. We report the case of a patient who suffered repeated, severe GI bleeding early after implantation of a HeartMate II continuous-flow LVAD. After failure of conventional treatment strategies, GI bleeding was controlled using repeated transfusions of a purified von Willebrand factor (VWF) concentrate, almost devoid of Factor VIII (Wilfactin, LFB). No episodes of pump thrombosis were noted. Subsequent to VWF transfusions, we observed a progressive normalization of circulating vascular endothelial growth factor levels. Our data raise the possibility that, in addition to its hemostatic properties, transfusions of VWF might have acted as an antiangiogenic factor. © 2014 AABB.

Stratum corneum cytokines and skin irritation response to sodium lauryl sulfate.

PubMed

De Jongh, Cindy M; Verberk, Maarten M; Withagen, Carien E T; Jacobs, John J L; Rustemeyer, Thomas; Kezic, Sanja

2006-06-01

Little is known about cytokines involved in chronic irritant contact dermatitis. Individual cytokine profiles might explain at least part of the differences in the individual response to irritation. Our objective was to investigate the relation between baseline stratum corneum (SC) cytokine levels and the skin response to a single and a repeated irritation test. This study also aimed to determine changes in SC cytokine levels after repeated irritation. Transepidermal water loss (TEWL) and erythema were measured in 20 volunteers after single 24-hr exposure to 1% sodium lauryl sulfate (SLS), and during and after repeated exposure to 0.1% SLS over a 3-week period. SC cytokine levels were measured from an unexposed skin site and from the repeatedly exposed site. Interleukin (IL)-1alpha decreased by 30% after repeated exposure, while IL-1RA increased 10-fold and IL-8 increased fourfold. Baseline IL-1RA and IL-8 values were predictors of TEWL and erythema after single exposure (r = 0.55-0.61). 6 subjects showed barrier recovery during repeated exposure. Baseline IL-1RA and IL-8 levels are likely to be indicators of higher skin irritability after single exposure to SLS. Barrier repair in some of the subjects might explain the lack of agreement between the TEWL response after single and repeated irritation.

Reduced biceps femoris myoelectrical activity influences eccentric knee flexor weakness after repeat sprint running.

PubMed

Timmins, R G; Opar, D A; Williams, M D; Schache, A G; Dear, N M; Shield, A J

2014-08-01

The aim of this study was to determine whether declines in knee flexor strength following overground repeat sprints were related to changes in hamstrings myoelectrical activity. Seventeen recreationally active men completed maximal isokinetic concentric and eccentric knee flexor strength assessments at 180°/s before and after repeat sprint running. Myoelectrical activity of the biceps femoris (BF) and medial hamstrings (MHs) was measured during all isokinetic contractions. Repeated measures mixed model [fixed factors = time (pre- and post-repeat sprint) and leg (dominant and nondominant), random factor = participants] design was fitted with the restricted maximal likelihood method. Repeat sprint running resulted in significant declines in eccentric, and concentric, knee flexor strength (eccentric = 26 ± 4 Nm, 15% P < 0.001; concentric 11 ± 2 Nm, 10% P < 0.001). Eccentric BF myoelectrical activity was significantly reduced (10%; P = 0.035). Concentric BF and all MH myoelectrical activity were not altered. The declines in maximal eccentric torque were associated with the change in eccentric BF myoelectrical activity (P = 0.013). Following repeat sprint running, there were preferential declines in the myoelectrical activity of the BF, which explained declines in eccentric knee flexor strength. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Self-Criticism: A Measure of Uncompassionate Behaviors Toward the Self, Based on the Negative Components of the Self-Compassion Scale.

PubMed

Montero-Marín, Jesús; Gaete, Jorge; Demarzo, Marcelo; Rodero, Baltasar; Lopez, Luiz C Serrano; García-Campayo, Javier

2016-01-01

The use of the Self-Compassion Scale (SCS) as a single measure has been pointed out as problematic by many authors and its originally proposed structure has repeatedly been called into question. The negative facets of this construct are more strongly related to psychopathology than the positive indicators. The aim of this study was to evaluate and compare the different structures proposed for the SCS, including a new measure based only on the negative factors, and to assess the psychometric features of the more plausible solution. The study employed a cross-sectional and cross-cultural design. A sample of Brazilian (n = 406) and Spanish (n = 416) primary care professionals completed the SCS, and other questionnaires to measure psychological health-related variables. The SCS factor structure was estimated using confirmatory factor analysis by the maximum likelihood method. Internal consistency was assessed by squaring the correlation between the latent true variable and the observed variables. The relationships between the SCS and other constructs were analyzed using Spearman's r s . The structure with the best fit was comprised of the three negative first-order factors of "self-judgment", "isolation" and "over-identification", and one negative second-order factor, which has been named "self-criticism" [CFI = 0.92; RMSEA = 0.06 (90% CI = 0.05-0.07); SRMR = 0.05]. This solution was supported by both samples, presented partial metric invariance [CFI = 0.91; RMSEA = 0.06 (90% CI = 0.05-0.06); SRMR = 0.06], and showed significant correlations with other health-related psychological constructs. Reliability was adequate for all the dimensions (R ≥ 0.70). The original structure proposed for the SCS was not supported by the data. Self-criticism, comprising only the negative SCS factors, might be a measure of uncompassionate behaviors toward the self, with good psychometric properties and practical implications from a clinical point of view, reaching a stable structure and overcoming possible methodological artifacts.

Development and evaluation of the nurse quality of communication with patient questionnaire.

PubMed

Vuković, Mira; Gvozdenović, Branislav S; Stamatović-Gajić, Branka; Ilić, Miodrag; Gajić, Tomislav

2010-01-01

Nurse/patient relationship as a complex interrelation or as an interaction of the factor patient and factor nurse has been a subject of a number of studies during the past ten years. Nurse/patient communication is a special entity, usually observed within a framework of the wider nurse/patient relationship. In that regard, we wanted to develop a standardized questionnaire that could reliably measure the quality of communication between nurse and patient, and be used by nurses. The main goal of this study was to develop and evaluate construct validity of the Nurse Quality of Communication with Patient Questionnaire (NQCPQ), as well as to evaluate its reliability. The goal was also to establish a measure of inter-raters reliability, using two repeated measurements of results by items and scores of the NQCPQ, on the same observed units by two assessors. The starting NQCPQ that consists of 25 items, was filled in by two groups of nurses. Each nurse was questioned during morning and afternoon shifts, in order to evaluate their communication with hospitalized patients, using marks from 1 to 6. To evaluate construct validity, we used the analysis of main components, while reliability was assessed using intraclass correlation coefficient and Cronbach-alpha coefficient. To evaluate interraters reliability, we used Pearson correlation coefficient. Using a group of 118 patients, we explained 86% of the unknown, regarding the investigated phenomenon (communication nurse/patient), using one component by which we separated 6 items of the questionnaire. Inter-item correlation (alpha) in this component was 0.96. Pearson correlation coefficient was highly significant, value 0.7 by item, and correlation coefficient for scores at repeated measurements was 0.84. NQCPQ is 6-item instrument with high construct validity. It can be used to measure quality of nurse/patient communication in a simple, fast and reliable way. It could contribute to more adequate research and defining of this problem, and as such could be used in studies of interaction of psychometric, clinical, biochemical, socio-cultural, demographic and other parameters as well.

Determination of repeatability of kinect sensor.

PubMed

Bonnechère, Bruno; Sholukha, Victor; Jansen, Bart; Omelina, Lubos; Rooze, Marcel; Van Sint Jan, Serge

2014-05-01

The Kinect™ (Microsoft™, Redmond, WA) sensor, originally developed for gaming purposes, may have interesting possibilities for other fields such as posture and motion assessment. The ability of the Kinect sensor to perform biomechanical measurements has previously been studied and shows promising results. However, interday repeatability of the device is still not known. This study assessed the intra- and interday repeatability of the Kinect sensor compared with a standard stereophotogrammetric device during posture assessment for measuring segment lengths. Forty subjects took part in the study. Five motionless captures were performed in one session to assess posture. Data were simultaneously recorded with both devices. Similar intraclass correlations coefficient (ICC) values were found for intraday (ICC=0.94 for the Kinect device and 0.98 for the stereophotogrammetric device) and interday (ICC=0.88 and 0.87, respectively) repeatability. Results of this study suggest that a cost-effective, easy-to-use, and portable single markerless camera offers the same repeatability during posture assessment as an expensive, time-consuming, and nontransportable marker-based device.

Evolution of Determinant Factors of Repeated Sprint Ability.

PubMed

Pareja-Blanco, Fernando; Suarez-Arrones, Luis; Rodríguez-Rosell, David; López-Segovia, Manuel; Jiménez-Reyes, Pedro; Bachero-Mena, Beatriz; González-Badillo, Juan José

2016-12-01

The aim of this study was to investigate the changes in the relationships between repeated sprint ability (RSA) and anthropometric measures as well as fitness qualities in soccer players. Twenty-one professional soccer players performed several anthropometric and physical tests including countermovement vertical jumps (CMJs), a straight-line 30 m sprint (T30), an RSA test (6 x 20 + 20 m with 20 s recovery), a progressive isoinertial loading test in a full squat, a Yo-Yo Intermittent Recovery Test Level-1 (YYIRT-1) and a 20 m shuttle run test (20mSRT). The mean (RSAmean), the fastest (RSAbest), each single sprint time, and the percentage in a sprint decrease (%Dec) in the RSA test were calculated. RSAbest correlated significantly with RSAmean (r = .82) and with all single sprints (p < 0.05), showing a downward trend as the number of sprints performed increased. No significant relationship was observed between the %Dec and RSA performance. CMJs and the T30 also showed a correlation with RSA performance, whereas lower limb strength did not show any relationship with RSA performance. RSAmean showed significant (p < 0.05) relationships with body mass (r = .44), adiposity (r = .59) and the YYIRT-1 (r = -.62), increasing as the number of repeated sprints increased. The 20mSRT showed minimal relationships with RSA performance. In conclusion, maximal sprint capacity seems to be relevant for the RSA performance, mainly in the first sprints. However, high intermittent endurance capacity and low adiposity might help enhance the RSA performance when increasing the number of repeated sprints.

Evolution of Determinant Factors of Repeated Sprint Ability

PubMed Central

Suarez-Arrones, Luis; Rodríguez-Rosell, David; López-Segovia, Manuel; Jiménez-Reyes, Pedro; Bachero-Mena, Beatriz; González-Badillo, Juan José

2016-01-01

Abstract The aim of this study was to investigate the changes in the relationships between repeated sprint ability (RSA) and anthropometric measures as well as fitness qualities in soccer players. Twenty-one professional soccer players performed several anthropometric and physical tests including countermovement vertical jumps (CMJs), a straight-line 30 m sprint (T30), an RSA test (6 x 20 + 20 m with 20 s recovery), a progressive isoinertial loading test in a full squat, a Yo-Yo Intermittent Recovery Test Level-1 (YYIRT-1) and a 20 m shuttle run test (20mSRT). The mean (RSAmean), the fastest (RSAbest), each single sprint time, and the percentage in a sprint decrease (%Dec) in the RSA test were calculated. RSAbest correlated significantly with RSAmean (r = .82) and with all single sprints (p < 0.05), showing a downward trend as the number of sprints performed increased. No significant relationship was observed between the %Dec and RSA performance. CMJs and the T30 also showed a correlation with RSA performance, whereas lower limb strength did not show any relationship with RSA performance. RSAmean showed significant (p < 0.05) relationships with body mass (r = .44), adiposity (r = .59) and the YYIRT-1 (r = -.62), increasing as the number of repeated sprints increased. The 20mSRT showed minimal relationships with RSA performance. In conclusion, maximal sprint capacity seems to be relevant for the RSA performance, mainly in the first sprints. However, high intermittent endurance capacity and low adiposity might help enhance the RSA performance when increasing the number of repeated sprints. PMID:28031763

Mechanisms of force depression caused by different types of physical exercise studied by direct electrical stimulation of human quadriceps muscle.

PubMed

Skurvydas, Albertas; Mamkus, Gediminas; Kamandulis, Sigitas; Dudoniene, Vilma; Valanciene, Dovile; Westerblad, Håkan

2016-12-01

Force production frequently remains depressed for several hours or even days after various types of strenuous physical exercise. We hypothesized that the pattern of force changes during the first hour after exercise can be used to reveal muscular mechanisms likely to underlie the decline in muscle performance during exercise as well as factors involved in the triggering the prolonged force depression after exercise. Nine groups of recreationally active male volunteers performed one of the following types of exercise: single prolonged or repeated short maximum voluntary contractions (MVCs); single or repeated all-out cycling bouts; repeated drop jumps. The isometric force of the right quadriceps muscle was measured during stimulation with brief 20 and 100 Hz trains of electrical pulses given before and at regular intervals for 60 min after exercise. All exercises resulted in a prolonged force depression, which was more marked at 20 Hz than at 100 Hz. Short-lasting (≤2 min) MVC and all-out cycling exercises showed an initial force recovery (peak after ~ 5 min) followed by a secondary force depression. The repeated drop jumps, which involve eccentric contractions, resulted in a stable force depression with the 20 Hz force being markedly more decreased after 100 than 10 jumps. In accordance with our hypothesis, the results propose at least three different mechanisms that influence force production after exercise: (1) a transiently recovering process followed by (2) a prolonged force depression after metabolically demanding exercise, and (3) a stable force depression after mechanically demanding contractions.

Occupational factors and subsequent major depressive and generalized anxiety disorders in the prospective French national SIP study.

PubMed

Niedhammer, Isabelle; Malard, Lucile; Chastang, Jean-François

2015-02-28

The literature has been extensive on the associations between psychosocial work factors and mental health. Nevertheless, the studies using prospective design, various concepts and more than one measurement point in time for these factors and diagnostic interview to assess mental disorders remain seldom in the literature. This study is an attempt to fill the gap in this topic. The study was based on a national representative sample of 4717 workers of the French working population (SIP survey), interviewed in 2006 and reinterviewed again in 2010 and free of mental disorders at baseline. Psychosocial work factors, measured in both 2006 and 2010, included: psychological demands, decision latitude, social support, reward, emotional demands, role conflict, ethical conflict, tensions with the public, job insecurity and work-life imbalance. Other occupational factors related to working time/hours and physical work environment were also studied. Major depressive (MDD) and generalized anxiety disorders (GAD) were measured using a standardised diagnostic interview (MINI). Covariates were age, occupation, marital status, having a child under 3 y, social support outside work and stressful life events. Multivariate analyses were performed using weighted logistic regression models. Using models taking all occupational factors into account simultaneously, low reward and job insecurity predicted MDD. Psychological demands, low reward, emotional demands and job insecurity were predictive of GAD. The more frequent the exposure to job insecurity, the higher the risk of MDD and GAD, and the more frequent the exposure to psychological demands and low reward, the higher the risk of GAD. No effect was observed for repeated exposure to occupational factors. Classical and emergent psychosocial work factors were predictive factors of depression and anxiety with dose-response associations in terms of frequency of exposure. More attention may be needed on emergent psychosocial work factors and frequent exposure to these factors.

Biochemical and structural characterization of a novel cooperative binding mode by Pit-1 with CATT repeats in the macrophage migration inhibitory factor promoter

PubMed Central

Agarwal, Sorabh

2018-01-01

Abstract Overexpression of the proinflammatory cytokine macrophage migration inhibitory factor (MIF) is linked to a number of autoimmune diseases and cancer. MIF production has been correlated to the number of CATT repeats in a microsatellite region upstream of the MIF gene. We have characterized the interaction of pituitary-specific positive transcription factor 1 (Pit-1) with a portion of the MIF promoter region flanking a microsatellite polymorphism (−794 CATT5–8). Using fluorescence anisotropy, we quantified tight complex formation between Pit-1 and an oligonucleotide consisting of eight consecutive CATT repeats (8xCATT) with an apparent Kd of 35 nM. Using competition experiments we found a 23 base pair oligonucleotide with 4xCATT repeats to be the minimum DNA sequence necessary for high affinity interaction with Pit-1. The stoichiometry of the Pit-1 DNA interaction was determined to be 2:1 and binding is cooperative in nature. We subsequently structurally characterized the complex and discovered a completely novel binding mode for Pit-1 in contrast to previously described Pit-1 complex structures. The affinity of Pit-1 for the CATT target sequence was found to be highly dependent on cooperativity. This work lays the groundwork for understanding transcriptional regulation of MIF and pursuing Pit-1 as a therapeutic target to treat MIF-mediated inflammatory disorders. PMID:29186613

Repeat retail clinic visits: impact of insurance coverage and age of patient.

PubMed

Angstman, Kurt B; Bernard, Matthew E; Rohrer, James E; Garrison, Gregory M; Maclaughlin, Kathy L

2012-12-01

As retail clinics provide a less costly alternative for health care, it would be reasonable to expect an increase in multiple (repeat) retail visits by those patients who may have expenses for receiving primary care. If costs were not a significant factor, then repeat visits should not be significantly different between these patients and those with coverage for primary care visits. The hypothesis for this study was that patients with the potential for out-of-pocket expenses would have a higher frequency of repeat retail clinic visits within 180 days compared to those with primary care coverage. A retrospective chart review was conducted of 5703 patients utilizing a retail clinic in Rochester, Minnesota from January 1, 2009 through June 30, 2009. The first visit to the retail clinic was considered the index visit and the chart was reviewed for repeat retail clinic visits within the next 180 days. Using a multiple logistic regression model, the odds of a pediatric patient (N=2344) having a repeat retail visit within 180 days of the index visit were not significantly impacted by insurance coverage (P=0.4209). Of the 3359 adult patients, those with unknown coverage had a 25.6% higher odds ratio of repeat retail clinic visits than those with insurance coverage (odds ratio 1.2557, confidence interval 1.0421-1.5131). This study suggested that when cost is an issue, the adult patient may favor retail clinics for episodic, low-acuity health care. In contrast, the pediatric population did not, suggesting that other factors, such as convenience, may play more of a role in the choice of episodic health care for this age group.

Repeat workers' compensation claims: risk factors, costs and work disability

PubMed Central

2011-01-01

Background The objective of our study was to describe factors associated with repeat workers' compensation claims and to compare the work disability arising in workers with single and multiple compensation claims. Methods All initial injury claims lodged by persons of working age during a five year period (1996 to 2000) and any repeat claims were extracted from workers' compensation administrative data in the state of Victoria, Australia. Groups of workers with single and multiple claims were identified. Descriptive analysis of claims by affliction, bodily location, industry segment, occupation, employer and workplace was undertaken. Survival analysis determined the impact of these variables on the time between the claims. The economic impact and duration of work incapacity associated with initial and repeat claims was compared between groups. Results 37% of persons with an initial claim lodged a second claim. This group contained a significantly greater proportion of males, were younger and more likely to be employed in manual occupations and high-risk industries than those with single claims. 78% of repeat claims were for a second injury. Duration between the claims was shortest when the working conditions had not changed. The initial claims of repeat claimants resulted in significantly (p < 0.001) lower costs and work disability than the repeat claims. Conclusions A substantial proportion of injured workers experience a second occupational injury or disease. These workers pose a greater economic burden than those with single claims, and also experience a substantially greater cumulative period of work disability. There is potential to reduce the social, health and economic burden of workplace injury by enacting prevention programs targeted at these workers. PMID:21696637

Repeatability in Color Measurements of a Spectrophotometer using Different Positioning Devices.

PubMed

Hemming, Michael; Kwon, So Ran; Qian, Fang

2015-12-01

This study aimed to evaluate the repeatability of color measurements of an intraoral spectrophotometer with the use of three different methods by two operators. A total of 60 teeth were obtained, comprising 30 human maxillary teeth [central incisors (n = 10); canines (n = 10); molars (n = 10)] and 30 artificial teeth [lateral incisors (n = 10); premolar (n = 20)]. Multiple repeated color measurements were obtained from each tooth using three measuring methods by each of the two operators. Five typodonts with alternating artificial and human teeth were made. Measurements were taken by two operators with the Vita EasyShade spectrophotometer using the custom tray (CT), custom jig (CJ) and free hand (FH) method, twice, at an interval of 2 to 7 days. Friedman test was used to detect difference among the three color measuring methods. Post hoc Wilcoxon signed-rank test with Bonferroni correction applied was used for pair-wise comparison of color measurements among the three methods. Additionally, a paired-sample t-test was used to assess a significant difference between the two duplicated measurements made on the same tooth by the same operator for each color parameter and measuring method. For operator A, mean (SD) overall color change-ΔE* (SD) perceived for FH, CT and CJ were 2.21(2.00), 2.39 (1.58) and 2.86 (1.92), respectively. There was statistically significant difference in perceived ΔE* in FH vs CJ (p = 0.0107). However, there were no significant differences between FH and CT (p = 0.2829) or between CT and CJ (p = 0.1159). For operator B mean ΔE* (SD) for FH, CT and CJ were 3.24 (3.46), 1.95 (1.19) and 2.45 (1.56), respectively. There was a significant difference between FH and CT (p = 0.0031). However, there were no statistically significant differences in ΔE* in FH vs CJ (p = 0.3696) or CT vs CJ (p = 0.0809). The repeatability of color measurements was different among the three measuring methods by operators. Overall, the CT method worked well for both operators. The use of a custom tray with apertures can improve the repeatability of color measurements of an intraoral spectrophotometer.

Repeated social defeat and the rewarding effects of cocaine in adult and adolescent mice: dopamine transcription factors, proBDNF signaling pathways, and the TrkB receptor in the mesolimbic system.

PubMed

Montagud-Romero, Sandra; Nuñez, Cristina; Blanco-Gandia, M Carmen; Martínez-Laorden, Elena; Aguilar, María A; Navarro-Zaragoza, Javier; Almela, Pilar; Milanés, Maria-Victoria; Laorden, María-Luisa; Miñarro, José; Rodríguez-Arias, Marta

2017-07-01

Repeated social defeat (RSD) increases the rewarding effects of cocaine in adolescent and adult rodents. The aim of the present study was to compare the long-term effects of RSD on the conditioned rewarding effects of cocaine and levels of the transcription factors Pitx3 and Nurr1 in the ventral tegmental area (VTA), the dopamine transporter (DAT), the D2 dopamine receptor (D2DR) and precursor of brain-derived neurotrophic factor (proBDNF) signaling pathways, and the tropomyosin-related kinase B (TrkB) receptor in the nucleus accumbens (NAc) in adult and adolescent mice. Male adolescent and young adult OF1 mice were exposed to four episodes of social defeat and were conditioned 3 weeks later with 1 mg/kg of cocaine. In a second set of mice, the expressions of the abovementioned dopaminergic and proBDNF and TrkB receptor were measured in VTA and NAc, respectively. Adolescent mice experienced social defeats less intensely than their adult counterparts and produced lower levels of corticosterone. However, both adult and adolescent defeated mice developed conditioned place preference for the compartment associated with this low dose of cocaine. Furthermore, only adolescent defeated mice displayed diminished levels of the transcription factors Pitx3 in the VTA, without changes in the expression of DAT and D2DR in the NAc. In addition, stressed adult mice showed a decreased expression of proBDNF and the TrkB receptor, while stressed adolescent mice exhibited increased expression of latter without changes in the former. Our findings suggest that dopaminergic pathways and proBDNF signaling and TrkB receptors play different roles in social defeat-stressed mice exposed to cocaine.

Risk factors for repeat adverse asthma events in children after visiting an emergency department.

PubMed

To, Teresa; Wang, Chengning; Dell, Sharon; Fleming-Carroll, Bonnie; Parkin, Patricia; Scolnik, Dennis; Ungar, Wendy

2008-01-01

The aim of this study was to identify risk factors for long-term adverse outcomes in children with asthma after visiting the emergency department (ED). A prospective observational study was conducted at the ED of a pediatric tertiary hospital in Ontario, Canada. Patient outcomes (ie, acute asthma episodes and ED visits) were measured at baseline and at 1- and 6-months post-ED discharge. Time trends in outcomes were assessed using the generalized estimating equations method. Multiple conditional logistic regressions were used to model outcomes at 6 months and examine the impact of drug insurance coverage while adjusting for confounders. Of the 269 children recruited, 81.8% completed both follow-ups. ED use significantly reduced from 39.4% at baseline to 26.8% at 6 months (P < .001), whereas the level of acute asthma episodes remained unchanged. Children with drug insurance coverage were less likely to have acute asthma episodes (adjusted odds ratio [AOR] = 0.36; 95% CI, 0.15-0.85; P < .02) or repeat ED visits (AOR = 0.45; 95% CI, 0.20-0.99; P < .05) at 6 months. Other risk factors for adverse outcomes included previous adverse asthma events and certain asthma triggers (eg, cold/sinus infection). Washing bed linens in hot water weekly was protective against subsequent acute asthma episodes. Our study demonstrated significant improvements in long-term outcomes in children seeking acute care for asthma in the ED. Future efforts remain in targeting the sustainability of improved outcomes beyond 6 months. Risk factors identified can help target vulnerable populations for proper interventions, which may include efforts to maximize insurance coverage for asthma medications and strategies to improve asthma self-management through patient and provider education.

Prediction and repeatability of milk coagulation properties and curd-firming modeling parameters of ovine milk using Fourier-transform infrared spectroscopy and Bayesian models.

PubMed

Ferragina, A; Cipolat-Gotet, C; Cecchinato, A; Pazzola, M; Dettori, M L; Vacca, G M; Bittante, G

2017-05-01

The aim of this study was to apply Bayesian models to the Fourier-transform infrared spectroscopy spectra of individual sheep milk samples to derive calibration equations to predict traditional and modeled milk coagulation properties (MCP), and to assess the repeatability of MCP measures and their predictions. Data consisted of 1,002 individual milk samples collected from Sarda ewes reared in 22 farms in the region of Sardinia (Italy) for which MCP and modeled curd-firming parameters were available. Two milk samples were taken from 87 ewes and analyzed with the aim of estimating repeatability, whereas a single sample was taken from the other 915 ewes. Therefore, a total of 1,089 analyses were performed. For each sample, 2 spectra in the infrared region 5,011 to 925 cm -1 were available and averaged before data analysis. BayesB models were used to calibrate equations for each of the traits. Prediction accuracy was estimated for each trait and model using 20 replicates of a training-testing validation procedure. The repeatability of MCP measures and their predictions were also compared. The correlations between measured and predicted traits, in the external validation, were always higher than 0.5 (0.88 for rennet coagulation time). We confirmed that the most important element for finding the prediction accuracy is the repeatability of the gold standard analyses used for building calibration equations. Repeatability measures of the predicted traits were generally high (≥95%), even for those traits with moderate analytical repeatability. Our results show that Bayesian models applied to Fourier-transform infrared spectra are powerful tools for cheap and rapid prediction of important traits in ovine milk and, compared with other methods, could help in the interpretation of results. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Agreement and repeatability of objective systems for assessment of the tear film.

PubMed

Fernández, Joaquín; Rodríguez-Vallejo, Manuel; Martínez, Javier; Tauste, Ana; García-Montesinos, Javier; Piñero, David P

2018-04-18

To assess the agreement and repeatability of two objective systems for measuring the tear film stability. Retrospective analysis of the tear film stability of 99 healthy right eyes measured with a videokeratoscope (VK) and the Optical Quality Analysis System (OQAS, Visiometrics). Two consecutive measures were taken with both systems, with an interval of 10 min between them. Variables included in the study were first and mean non-invasive break-up times (NIBUT and MNIBUT) measured with VK, and mean and standard deviation of the optical scattering index (OSIm and OSIsd) measured with OQAS. The agreement and repeatability of grading scales provided by both devices were also evaluated using the Cohen's k with quadratic weights. The Ocular Surface Disease index (OSDI) questionnaire was also passed out to all subjects. Correlations and associations between subjective and objective metrics were analyzed. Significant differences were found between consecutive measurements of NIBUT (p = 0.04) and MNIBUT (p = 0.01), but not for OSIm (p = 0.11) and OSIsd (p = 0.50). Grading scales resulted in fair (k = 0.20) or poor agreement (k = 0.04) between systems depending if the first or second trial was considered. The repeatability of the grading scale was good for OQAS (k = 0.59) and fair for VK (k = 0.37). No significant correlations or associations were found between OSDI and any of the metrics obtained with both devices (p ≥ 0.36). The two devices evaluated cannot be used interchangeably for the assessment of tear film stability. Good intrasession repeatability was obtained for tear film grading of the OQAS whereas it was fair for VK.

Evaluation of Retinal and Choroidal Thickness by Swept-Source Optical Coherence Tomography: Repeatability and Assessment of Artifacts

PubMed Central

Mansouri, Kaweh; Medeiros, Felipe A.; Tatham, Andrew J.; Marchase, Nicholas; Weinreb, Robert N.

2017-01-01

PURPOSE To determine the repeatability of automated retinal and choroidal thickness measurements with swept-source optical coherence tomography (SS OCT) and the frequency and type of scan artifacts. DESIGN Prospective evaluation of new diagnostic technology. METHODS Thirty healthy subjects were recruited prospectively and underwent imaging with a prototype SS OCT instrument. Undilated scans of 54 eyes of 27 subjects (mean age, 35.1 ± 9.3 years) were obtained. Each subject had 4 SS OCT protocols repeated 3 times: 3-dimensional (3D) 6 × 6-mm raster scan of the optic disc and macula, radial, and line scan. Automated measurements were obtained through segmentation software. Interscan repeatability was assessed by intraclass correlation coefficients (ICCs). RESULTS ICCs for choroidal measurements were 0.92, 0.98, 0.80, and 0.91, respectively, for 3D macula, 3D optic disc, radial, and line scans. ICCs for retinal measurements were 0.39, 0.49, 0.71, and 0.69, respectively. Artifacts were present in up to 9% scans. Signal loss because of blinking was the most common artifact on 3D scans (optic disc scan, 7%; macula scan, 9%), whereas segmentation failure occurred in 4% of radial and 3% of line scans. When scans with image artifacts were excluded, ICCs for choroidal thickness increased to 0.95, 0.99, 0.87, and 0.93 for 3D macula, 3D optic disc, radial, and line scans, respectively. ICCs for retinal thickness increased to 0.88, 0.83, 0.89, and 0.76, respectively. CONCLUSIONS Improved repeatability of automated choroidal and retinal thickness measurements was found with the SS OCT after correction of scan artifacts. Recognition of scan artifacts is important for correct interpretation of SS OCT measurements. PMID:24531020

Repeatability of a dynamic rollover test system.

PubMed

Seppi, Jeremy; Toczyski, Jacek; Crandall, Jeff R; Kerrigan, Jason

2016-08-17

The goal of this study was to characterize the rollover crash and to evaluate the repeatability of the Dynamic Rollover Test System (DRoTS) in terms of initial roof-to-ground contact conditions, vehicle kinematics, road reaction forces, and vehicle deformation. Four rollover crash tests were performed on 2 pairs of replicate vehicles (2 sedan tests and 2 compact multipurpose van [MPV] tests), instrumented with a custom inertial measurement unit to measure vehicle and global kinematics and string potentiometers to measure pillar deformation time histories. The road was instrumented with load cells to measure reaction loads and an optical encoder to measure road velocity. Laser scans of pre- and posttest vehicles were taken to provide detailed deformation maps. Initial conditions were found to be repeatable, with the largest difference seen in drop height of 20 mm; roll rate, roll angle, pitch angle, road velocity, drop velocity, mass, and moment of inertia were all 7% different or less. Vehicle kinematics (roll rate, road speed, roll and pitch angle, global Z' acceleration, and global Z' velocity) were similar throughout the impact; however, differences were seen in the sedan tests because of a vehicle fixation problem and differences were seen in the MPV tests due to an increase in reaction forces during leading side impact likely caused by disparities in roll angle (3° difference) and mass properties (2.2% in moment of inertia [MOI], 53.5 mm difference in center of gravity [CG] location). Despite those issues, kinetic and deformation measures showed a high degree of repeatability, which is necessary for assessing injury risk in rollover because roof strength positively correlates with injury risk (Brumbelow 2009). Improvements of the test equipment and matching mass properties will ensure highly repeatable initial conditions, vehicle kinematics, kinetics, and deformations.

Validation of geometric measurements of the left atrium and pulmonary veins for analysis of reverse structural remodeling following ablation therapy

NASA Astrophysics Data System (ADS)

Rettmann, M. E.; Holmes, D. R., III; Gunawan, M. S.; Ge, X.; Karwoski, R. A.; Breen, J. F.; Packer, D. L.; Robb, R. A.

2012-03-01

Geometric analysis of the left atrium and pulmonary veins is important for studying reverse structural remodeling following cardiac ablation therapy. It has been shown that the left atrium decreases in volume and the pulmonary vein ostia decrease in diameter following ablation therapy. Most analysis techniques, however, require laborious manual tracing of image cross-sections. Pulmonary vein diameters are typically measured at the junction between the left atrium and pulmonary veins, called the pulmonary vein ostia, with manually drawn lines on volume renderings or on image cross-sections. In this work, we describe a technique for making semi-automatic measurements of the left atrium and pulmonary vein ostial diameters from high resolution CT scans and multi-phase datasets. The left atrium and pulmonary veins are segmented from a CT volume using a 3D volume approach and cut planes are interactively positioned to separate the pulmonary veins from the body of the left atrium. The cut plane is also used to compute the pulmonary vein ostial diameter. Validation experiments are presented which demonstrate the ability to repeatedly measure left atrial volume and pulmonary vein diameters from high resolution CT scans, as well as the feasibility of this approach for analyzing dynamic, multi-phase datasets. In the high resolution CT scans the left atrial volume measurements show high repeatability with approximately 4% intra-rater repeatability and 8% inter-rater repeatability. Intra- and inter-rater repeatability for pulmonary vein diameter measurements range from approximately 2 to 4 mm. For the multi-phase CT datasets, differences in left atrial volumes between a standard slice-by-slice approach and the proposed 3D volume approach are small, with percent differences on the order of 3% to 6%.

Reliability and repeatability of swept-source Fourier-domain optical coherence tomography and Scheimpflug imaging in keratoconus.

PubMed

Szalai, Eszter; Berta, András; Hassan, Ziad; Módis, László

2012-03-01

To evaluate the repeatability and reliability of a recently introduced swept-source Fourier-domain anterior segment optical coherence tomography (AS-OCT) system and a high-resolution Scheimpflug camera and to assess the agreement between the 2 instruments when measuring healthy eyes and eyes with keratoconus. Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary. Evaluation of diagnostic test or technology. Three consecutive series of anterior segment images were taken with AS-OCT (Casia SS-1000) followed by rotating Scheimpflug imaging (Pentacam high resolution). Axial keratometry in the steep and flat meridians and astigmatism values were recorded. Pachymetry in the apex, center, and the thinnest position and anterior chamber depth (ACD) measurements were also taken. This study enrolled 57 healthy volunteers (57 eyes) and 56 patients (84 eyes) with keratoconus. Significant difference was found in all measured anterior segment parameters between normal eyes and keratoconic eyes (P<.05). In keratoconic eyes, the difference between repeated measurements was less with AS-OCT than with Scheimpflug imaging in every keratometry and astigmatism value, in apical thickness, and in ACD. For keratometry, the thinnest and central pachymetry measurement repeatability was better in healthy eyes than in keratoconic eyes with both instruments. In general, the mean difference between AS-OCT and Scheimpflug imaging was higher in cases of keratoconus. Significant differences in keratometry, pachymetry, and ACD results were found between AS-OCT and Scheimpflug imaging. However, the repeatability of the measurements was comparable. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Trinucleotide repeat length and progression of illness in Huntington's disease.

PubMed Central

Kieburtz, K; MacDonald, M; Shih, C; Feigin, A; Steinberg, K; Bordwell, K; Zimmerman, C; Srinidhi, J; Sotack, J; Gusella, J

1994-01-01

The genetic defect causing Huntington's disease (HD) has been identified as an unstable expansion of a trinucleotide (CAG) repeat sequence within the coding region of the IT15 gene on chromosome 4. In 50 patients with manifest HD who were evaluated prospectively and uniformly, we examined the relationship between the extent of the DNA expansion and the rate of illness progression. Although the length of CAG repeats showed a strong inverse correlation with the age at onset of HD, there was no such relationship between the number of CAG repeats and the rate of clinical decline. These findings suggest that the CAG repeat length may influence or trigger the onset of HD, but other genetic, neurobiological, or environmental factors contribute to the progression of illness and the underlying pace of neuronal degeneration. PMID:7853373

Continuous monitoring of high-rise buildings using seismic interferometry

NASA Astrophysics Data System (ADS)

Mordret, A.; Sun, H.; Prieto, G. A.; Toksoz, M. N.; Buyukozturk, O.

2016-12-01

The linear seismic response of a building is commonly extracted from ambient vibration measurements. Seismic deconvolution interferometry performed on ambient vibration measurements can also be used to estimate the dynamic characteristics of a building, such as the velocity of shear-waves travelling inside the building as well as a damping parameter depending on the intrinsic attenuation of the building and the soil-structure coupling. The continuous nature of the ambient vibrations allows us to measure these parameters repeatedly and to observe their temporal variations. We used 2 weeks of ambient vibration recorded by 36 accelerometers installed in the Green Building on the Massachusetts Institute of Technology campus (Cambridge, MA) to continuously monitor the shear-wave speed and the attenuation factor of the building. Due to the low strain of the ambient vibrations, the observed changes are totally reversible. The relative velocity changes between a reference deconvolution function and the current deconvolution functions are measured with two different methods: 1) the Moving Window Cross-Spectral technique and 2) the stretching technique. Both methods show similar results. We show that measuring the stretching coefficient for the deconvolution functions filtered around the fundamental mode frequency is equivalent to measuring the wandering of the fundamental frequency in the raw ambient vibration data. By comparing these results with local weather parameters, we show that the relative air humidity is the factor dominating the relative seismic velocity variations in the Green Building, as well as the wandering of the fundamental mode. The one-day periodic variations are affected by both the temperature and the humidity. The attenuation factor, measured as the exponential decay of the fundamental mode waveforms, shows a more complex behaviour with respect to the weather measurements.

The effect of aroma stimulation during isotonic exercise on the rating of perceived exertion and blood fatigue factors of athletes with patellofemoral pain syndrome

PubMed Central

Kim, Sangsoo; Choo, JongHoo; Ju, Sungbum

2018-01-01

[Purpose] The purpose of this study is to examine the effect of aroma stimulation during isotonic exercise on the rating of perceived exertion (RPE) and the blood fatigue factors of athletes who have patellofemoral pain syndrome (PFPS). [Subjects and Methods] The research subjects were seven athletes in their twenties who suffer from PFPS. They were divided into a control group and an aroma stimulation group and performed isotonic exercises repeatedly. After exercising, the RPE and blood fatigue factors, including creatine phosphokinase (CPK), lactate dehydrogenase (LDH), and ammonia, were measured through blood sampling. [Results] The aroma stimulus group showed significantly lower RPE than the control group immediately after exercising, which included leg presses, leg curls, bicep curls, and leg extensions. Among the blood fatigue factors, the change in LDH indicated the effect of aroma stimulation. [Conclusion] We confirmed that aroma stimulation during isotonic exercise has the positive effect of reducing the RPE and blood fatigue factors, such as blood LDH, of the athletes with PFPS. PMID:29545683

The influence of individual and organisational factors on nurses' behaviour to use lifting devices in healthcare.

PubMed

Koppelaar, E; Knibbe, J J; Miedema, H S; Burdorf, A

2013-07-01

This study evaluates the influence of individual and organisational factors on nurses' behaviour to use lifting devices in healthcare. Interviews among nurses were conducted to collect individual characteristics and to establish their behaviour regarding lifting devices use. Organisational factors were collected by questionnaires and walk-through-surveys, comprising technical facilities, organisation of care, and management-efforts. Generalised-Estimating-Equations for repeated measurements were used to estimate determinants of nurses' behaviour. Important determinants of nurses' behaviour to use lifting devices were knowledge of workplace procedures (OR = 5.85), strict guidance on required lifting devices use (OR = 2.91), and sufficient lifting devices (OR = 1.92). Management-support and supportive-management-climate were associated with these determinants. Since nurses' behaviour to use lifting devices is influenced by factors at different levels, studies in ergonomics should consider how multi-level factors impact each other. An integral approach, addressing individual and organisational levels, is necessary to facilitate appropriate implementation of ergonomic interventions, like lifting devices. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Repeatability of chemical-shift-encoded water-fat MRI and diffusion-tensor imaging in lower extremity muscles in children.

PubMed

Ponrartana, Skorn; Andrade, Kristine E; Wren, Tishya A L; Ramos-Platt, Leigh; Hu, Houchun H; Bluml, Stefan; Gilsanz, Vicente

2014-06-01

The purpose of this study was to assess the repeatability of water-fat MRI and diffusion-tensor imaging (DTI) as quantitative biomarkers of pediatric lower extremity skeletal muscle. MRI at 3 T of a randomly selected thigh and lower leg of seven healthy children was studied using water-fat separation and DTI techniques. Muscle-fat fraction, apparent diffusion coefficient (ADC), and fractional anisotropy (FA) values were calculated. Test-retest and interrater repeatability were assessed by calculating the Pearson correlation coefficient, intraclass correlation coefficient, and Bland-Altman analysis. Bland-Altman plots show that the mean difference between test-retest and interrater measurements of muscle-fat fraction, ADC, and FA was near 0. The correlation coefficients and intraclass correlation coefficients were all between 0.88 and 0.99 (p < 0.05), suggesting excellent reliability of the measurements. Muscle-fat fraction measurements from water-fat MRI exhibited the highest intraclass correlation coefficient. Interrater agreement was consistently better than test-retest comparisons. Water-fat MRI and DTI measurements in lower extremity skeletal muscles are objective repeatable biomarkers in children. This knowledge should aid in the understanding of the number of participants needed in clinical trials when using these determinations as an outcome measure to noninvasively monitor neuromuscular disease.

Interindividual variation in thermal sensitivity of maximal sprint speed, thermal behavior, and resting metabolic rate in a lizard.

PubMed

Artacho, Paulina; Jouanneau, Isabelle; Le Galliard, Jean-François

2013-01-01

Studies of the relationship of performance and behavioral traits with environmental factors have tended to neglect interindividual variation even though quantification of this variation is fundamental to understanding how phenotypic traits can evolve. In ectotherms, functional integration of locomotor performance, thermal behavior, and energy metabolism is of special interest because of the potential for coadaptation among these traits. For this reason, we analyzed interindividual variation, covariation, and repeatability of the thermal sensitivity of maximal sprint speed, preferred body temperature, thermal precision, and resting metabolic rate measured in ca. 200 common lizards (Zootoca vivipara) that varied by sex, age, and body size. We found significant interindividual variation in selected body temperatures and in the thermal performance curve of maximal sprint speed for both the intercept (expected trait value at the average temperature) and the slope (measure of thermal sensitivity). Interindividual differences in maximal sprint speed across temperatures, preferred body temperature, and thermal precision were significantly repeatable. A positive relationship existed between preferred body temperature and thermal precision, implying that individuals selecting higher temperatures were more precise. The resting metabolic rate was highly variable but was not related to thermal sensitivity of maximal sprint speed or thermal behavior. Thus, locomotor performance, thermal behavior, and energy metabolism were not directly functionally linked in the common lizard.

Psychometric assessment of a scale to measure bonding workplace social capital

PubMed Central

Tsutsumi, Akizumi; Inoue, Akiomi; Odagiri, Yuko

2017-01-01

Objectives Workplace social capital (WSC) has attracted increasing attention as an organizational and psychosocial factor related to worker health. This study aimed to assess the psychometric properties of a newly developed WSC scale for use in work environments, where bonding social capital is important. Methods We assessed the psychometric properties of a newly developed 6-item scale to measure bonding WSC using two data sources. Participants were 1,650 randomly selected workers who completed an online survey. Exploratory factor analyses were conducted. We examined the item–item and item–total correlations, internal consistency, and associations between scale scores and a previous 8-item measure of WSC. We evaluated test–retest reliability by repeating the survey with 900 of the respondents 2 weeks later. The overall scale reliability was quantified by an intraclass coefficient and the standard error of measurement. We evaluated convergent validity by examining the association with several relevant workplace psychosocial factors using a dataset from workers employed by an electrical components company (n = 2,975). Results The scale was unidimensional. The item–item and item–total correlations ranged from 0.52 to 0.78 (p < 0.01) and from 0.79 to 0.89 (p < 0.01), respectively. Internal consistency was good (Cronbach’s α coefficient: 0.93). The correlation with the 8-item scale indicated high criterion validity (r = 0.81) and the scale showed high test–retest reliability (r = 0.74, p < 0.01). The intraclass coefficient and standard error of measurement were 0.74 (95% confidence intervals: 0.71–0.77) and 4.04 (95% confidence intervals: 1.86–6.20), respectively. Correlations with relevant workplace psychosocial factors showed convergent validity. Conclusions The results confirmed that the newly developed WSC scale has adequate psychometric properties. PMID:28662058

Angle performance on optima MDxt

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

David, Jonathan; Kamenitsa, Dennis

2012-11-06

Angle control on medium current implanters is important due to the high angle-sensitivity of typical medium current implants, such as halo implants. On the Optima MDxt, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through six narrow slits, and any angle adjustment is made by electrostatically steering the beam, while cross-wafer beam parallelism is adjusted by changing the focus of the electrostatic parallelizing lens (P-lens). In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightlymore » tilting the wafer platen prior to implant. A variety of tests were run to measure the accuracy and repeatability of Optima MDxt's angle control. SIMS profiles of a high energy, channeling sensitive condition show both the cross-wafer angle uniformity, along with the small-angle resolution of the system. Angle repeatability was quantified by running a channeling sensitive implant as a regular monitor over a seven month period and measuring the sheet resistance-to-angle sensitivity. Even though crystal cut error was not controlled for in this case, when attributing all Rs variation to angle changes, the overall angle repeatability was measured as 0.16 Degree-Sign (1{sigma}). A separate angle repeatability test involved running a series of V-curves tests over a four month period using low crystal cut wafers selected from the same boule. The results of this test showed the angle repeatability to be <0.1 Degree-Sign (1{sigma}).« less

Repeatability of quantitative FDG-PET/CT and contrast-enhanced CT in recurrent ovarian carcinoma: test-retest measurements for tumor FDG uptake, diameter, and volume.

PubMed

Rockall, Andrea G; Avril, Norbert; Lam, Raymond; Iannone, Robert; Mozley, P David; Parkinson, Christine; Bergstrom, Donald; Sala, Evis; Sarker, Shah-Jalal; McNeish, Iain A; Brenton, James D

2014-05-15

Repeatability of baseline FDG-PET/CT measurements has not been tested in ovarian cancer. This dual-center, prospective study assessed variation in tumor 2[18F]fluoro-2-deoxy-D-glucose (FDG) uptake, tumor diameter, and tumor volume from sequential FDG-PET/CT and contrast-enhanced computed tomography (CECT) in patients with recurrent platinum-sensitive ovarian cancer. Patients underwent two pretreatment baseline FDG-PET/CT (n = 21) and CECT (n = 20) at two clinical sites with different PET/CT instruments. Patients were included if they had at least one target lesion in the abdomen with a standardized uptake value (SUV) maximum (SUVmax) of ≥ 2.5 and a long axis diameter of ≥ 15 mm. Two independent reading methods were used to evaluate repeatability of tumor diameter and SUV uptake: on site and at an imaging clinical research organization (CRO). Tumor volume reads were only performed by CRO. In each reading set, target lesions were independently measured on sequential imaging. Median time between FDG-PET/CT was two days (range 1-7). For site reads, concordance correlation coefficients (CCC) for SUVmean, SUVmax, and tumor diameter were 0.95, 0.94, and 0.99, respectively. Repeatability coefficients were 16.3%, 17.3%, and 8.8% for SUVmean, SUVmax, and tumor diameter, respectively. Similar results were observed for CRO reads. Tumor volume CCC was 0.99 with a repeatability coefficient of 28.1%. There was excellent test-retest repeatability for FDG-PET/CT quantitative measurements across two sites and two independent reading methods. Cutoff values for determining change in SUVmean, SUVmax, and tumor volume establish limits to determine metabolic and/or volumetric response to treatment in platinum-sensitive relapsed ovarian cancer. ©2014 American Association for Cancer Research.

Psychological as well as illness factors influence acceptance of non-invasive ventilation (NIV) and gastrostomy in amyotrophic lateral sclerosis (ALS): a prospective population study.

PubMed

Martin, Naomi H; Landau, Sabine; Janssen, Anna; Lyall, Rebecca; Higginson, Irene; Burman, Rachel; McCrone, Paul; Sakel, Mohammed; Ellis, Catherine M; Shaw, Christopher E; Al-Chalabi, Ammar; Leigh, P Nigel; Goldstein, Laura H

2014-09-01

Our objective was to identify factors associated with acceptance of non-invasive ventilation (NIV) and gastrostomy in an exploratory population-based study. Seventy-eight people with ALS at least six months post-diagnosis, and 50 caregivers, were recruited from the South-East ALS Register. Baseline physical, cognitive and psychological measures were obtained. Three-monthly follow-ups monitored whether patients had accepted or refused NIV or gastrostomy. Following an intervention decision, post-decision interviews repeated baseline measures and included further intervention-specific questionnaires. Results showed that 32 people with ALS made at least one intervention decision and of these 10 decided about both NIV and gastrostomy. While illness factors predicted those needing to make an intervention decision, cognitive and education status, and level of executive dysfunction were associated with decision-making and acceptance or refusal of interventions. Patients' understanding of their illness, their early approach to considering interventions and carer-related factors were also associated with treatment decisions. In conclusion, our findings highlight the complexity of decision-making and provide a platform for designing further studies. Cognitive and psychosocial factors may assume a greater role in palliative care decisions for people with ALS than has been explicitly recognized. Future work must clarify how to ensure patients are not inadvertently being denied suitable interventions.

Changing negative stereotypes regarding aging in undergraduate nursing students.

PubMed

Sarabia-Cobo, C M; Castanedo Pfeiffer, C

2015-09-01

The aim of this study was to explore the modification of stereotypes and myths regarding aging among third-year nursing students before and after undergoing an Aging Nursing course. A within-subject repeated-measures descriptive study was conducted. The Negative Stereotypes Questionnaire about Aging (CENVE) was used. The overall prevalence of negative stereotypes was 62.0% pre-intervention (P1) and 12.3% post-intervention (P2) measured; these values were 63.5% (P1) and 9.2% (P2) for the health factor, 43.1% (P1) and 4.9% (P2) for the motivation and social factors and 58.3% (P1) and 3.8% (P2) for the character-personality factor. Paired Student's t tests confirmed that the differences were statistically significant. There was a high prevalence of negative stereotypes toward aging among the nursing students, even though they had conducted clinical practice and were in their third year. The course was demonstrated to be effective in modifying these stereotypes. The proper training of future professionals markedly contributes the dispensation of proper care and the eradication of ageism, which remains prevalent in the healthcare system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Glucose regulation is associated with cognitive performance in young nondiabetic adults.

PubMed

Messier, Claude; Awad-Shimoon, Nesrine; Gagnon, Michèle; Desrochers, Alain; Tsiakas, Maria

2011-09-12

Several studies have documented an increased incidence of dementia among diabetic patients. In addition, impaired glucose regulation in both, younger and older adults, has been shown to be associated with neuropsychological deficits, particularly of episodic memory. The main purpose of this study was to examine this association in a large sample of young nondiabetic adults. All participants underwent a glucose tolerance test together with measures of insulin levels and lipids. Regression analyses revealed that glucoregulatory indices based on evoked glucose levels were significantly associated with the verbal memory performance of 122 young adults, independent of demographic and vascular risk factors. Participants were assessed after drinking glucose or saccharin, using a repeated-measures design. There was no effect of glucose on cognitive performance. Glucoregulatory indices calculated on the basis of insulin levels or fasting glucose levels explained less cognitive variability compared to indices based on evoked glucose levels. Cardiovascular risk factors were associated with hyperinsulinemia but these factors were not associated with cognitive performance in this young adult group. These findings suggest that cognitive decrements are observable in young, nondiabetic adults, prior to the onset of impaired glucose regulation and diabetes. Copyright © 2011 Elsevier B.V. All rights reserved.

An Investigation of Factors Affecting the Degree of Naïve Impetus Theory Application

NASA Astrophysics Data System (ADS)

Liu, Xiufeng; MacIsaac, Dan

2005-03-01

This study investigates factors affecting the degree of novice physics students' application of the naïve impetus theory. Six hundred and fourteen first-year university engineering physics students answered the Force Concept Inventory as a pre-test for their calculus-based course. We examined the degree to which students consistently applied the naïve impetus theory across different items. We used a 2-way repeated measures ANOVA and linear regression to analyze data coded from incorrect student responses. It was found that there were statistically significant main effects for item familiarity and item requirement for explanation vs. prediction on the measured degree of impetus theory application. Student course grades had no significant effect on impetus theory application. When faced with items that were unfamiliar and predictive, students appeared to rely on non-theoretical, knowledge-in-pieces reasoning. Reasoning characteristic of naïve theories was more frequently applied when students were completing familiar problem tasks that required explanation. When considering all the above factors simultaneously, we found that the degree of naïve impetus theory application by students is attributable to variables in the following order: familiarity, prediction, and explanation.

Sensitivity of measurement-based purification processes to inner interactions

NASA Astrophysics Data System (ADS)

Militello, Benedetto; Napoli, Anna

2018-02-01

The sensitivity of a repeated measurement-based purification scheme to additional undesired couplings is analyzed, focusing on the very simple and archetypical system consisting of two two-level systems interacting with a repeatedly measured one. Several regimes are considered and in the strong coupling limit (i.e., when the coupling constant of the undesired interaction is very large) the occurrence of a quantum Zeno effect is proven to dramatically jeopardize the efficiency of the purification process.

Method Effects on an Adaptation of the Rosenberg Self-Esteem Scale in Greek and the Role of Personality Traits.

PubMed

Michaelides, Michalis P; Koutsogiorgi, Chrystalla; Panayiotou, Georgia

2016-01-01

Rosenberg's Self-Esteem Scale is a balanced, 10-item scale designed to be unidimensional; however, research has repeatedly shown that its factorial structure is contaminated by method effects due to item wording. Beyond the substantive self-esteem factor, 2 additional factors linked to the positive and negative wording of items have been theoretically specified and empirically supported. Initial evidence has revealed systematic relations of the 2 method factors with variables expressing approach and avoidance motivation. This study assessed the fit of competing confirmatory factor analytic models for the Rosenberg Self-Esteem Scale using data from 2 samples of adult participants in Cyprus. Models that accounted for both positive and negative wording effects via 2 latent method factors had better fit compared to alternative models. Measures of experiential avoidance, social anxiety, and private self-consciousness were associated with the method factors in structural equation models. The findings highlight the need to specify models with wording effects for a more accurate representation of the scale's structure and support the hypothesis of method factors as response styles, which are associated with individual characteristics related to avoidance motivation, behavioral inhibition, and anxiety.

The Effects of Group Leader Learning Style on Student Knowledge Gain in a Leadership Camp Setting: A Repeated-Measures Experiment

ERIC Educational Resources Information Center

Brown, Nicholas R.; Terry, Robert, Jr.

2013-01-01

Many state FFA associations conduct summer camps focusing on leadership and personal development for FFA members. Interestingly, little research has been conducted on the impact or outcomes of these common activities. The purpose of this split-plot factorial repeated-measures experiment was to assess the level of campers' learning of the…