Search results for "Small sample"
showing 10 items of 32 documents
Dental pulp calcifications in prehistoric and historical skeletal remains
2020
Abstract Background The prevalence of hard tissue formations in the dental pulp varies considerably. Beside ageing processes and irritations of the dental pulp, etiological associations with cardiovascular disease and dietary habits have been discussed, which are of particular research interest. The aim of this pilot study is to provide new insights on structural and etiological factors involved in the development of pulp calcifications by investigating skeletal remains from different (pre)historic periods. Methods The jaws of 46 skeletons excavated in central Germany, were examined for the presence of pulp stones using digital volume tomography (DVT). A total of 1122 teeth were examined wi…
Do vegetarians feel bad? Examining the association between eating vegetarian and subjective well-being in two representative samples
2020
Abstract Research on the relationship between vegetarianism and subjective well-being (SWB) has produced inconsistent results, which may partly be due to small sample sizes and divergent operationalizations of well-being. For these reasons, the present study aimed to thoroughly examine this association in two large representative samples from Germany (Study 1: N = 12,905, including 665 vegetarians) and Australia (Study 2: N = 15,532, including 383 vegetarians) using a consensual conceptualization of SWB (composed of an affective component, i.e., positive and negative affect, and a cognitive component, i.e., life satisfaction). Results of t-tests showed that vegetarians reported slightly hig…
Objective measurement of intraocular forward light scatter using Hartmann-Shack spot patterns from clinical aberrometers. Model-eye and human-eye stu…
2007
Purpose To apply software-based image-analysis tools to objectively determine intraocular scatter determined from clinically derived Hartmann-Shack patterns. Setting Aston Academy of Life Sciences, Aston University, Birmingham, United Kingdom, and Department of Optics, University of Valencia, Valencia, Spain. Methods Purpose-designed image-analysis software was used to quantify scatter from centroid patterns obtained using a clinical Hartmann-Shack analyzer (WASCA, Zeiss/Meditec). Three scatter values, as the maximum standard deviation within a lenslet for all lenslets in the pattern, were obtained in 6 model eyes and 10 human eyes. In the model-eye sample, patterns were obtained in 4 sessi…
Assessing thoraco-pelvic covariation in Homo sapiens and Pan troglodytes: A 3D geometric morphometric approach
2019
[Objectives]: Understanding thoraco-pelvic integration in Homo sapiens and their closest living relatives (genus Pan) is of great importance within the context of human body shape evolution. However, studies assessing thoraco-pelvic covariation across Hominoidea species are scarce, although recent research would suggest shared covariation patterns in humans and chimpanzees but also species-specific features, with sexual dimorphism and allometry influencing thoraco-pelvic covariation in these taxa differently.
The implicit health-related self-concept in somatoform disorders.
2012
Abstract Background and objective Dual-process theories stress the importance of explicit as well as implicit cognitive processes for the development of somatoform disorders (SFDs). 1 In particular, the self-concept has been demonstrated to be a key factor in SFD. Yet, the self-concept in SFDs has been studied only on an explicit but not on an implicit level. Methods The present study empirically examined the implicit health-related self-concept in SFDs by using the Implicit Association Test (IAT). Twenty-two patients with SFDs (according to DSM-IV) and 27 healthy control participants (CG) completed an IAT to assess associations of the self with illness- versus health-related words. Results…
Prospective randomized comparison of short-access mother-baby cholangioscopy versus direct cholangioscopy with ultraslim gastroscopes
2012
Mother-baby technologies, the criterion standard for cholangioscopy, have several limitations. A novel, short-access, mother-baby (SAMBA) system may improve this technique. Direct cholangioscopy (DC) was recently developed as an alternative to mother-baby cholangioscopy.Comparison of success rates with SAMBA and DC.Single-center, randomized, controlled trial.Academic tertiary-care referral center.Sixty patients with suspected cholangiopathies randomized to either SAMBA (n = 30) or DC (n = 30).Cholangioscopy under deep sedation.Technical success rate of diagnostic or therapeutic procedure.A total of 24 and 21 diagnostic procedures were performed in the SAMBA and DC groups, respectively. Ther…
Real-time polarimetric biosensing using macroporous alumina membranes
2013
We report the first demonstration of real-time biosensing in free standing macroporous alumina membranes. The membranes with their 200 nm diameter pores are ideal candidates for biosensing applications where fast response times for small sample volumes are needed as they allow analytes to flow through the pores close to the bioreceptors immobilized on the pores walls. A bulk refractive index sensitivity of 5.2x10 -6 refractive index units was obtained from signal responses to different concentrations of NaCl solutions flowing through the pores. Finally, after functionalizing the alumina pore surfaces with an epoxysilane and then spotting it with β-Lactoglobulin protein, the interactions bet…
NEW FRAMES OF ARCHAEOMETRICAL DESCRIPTION OF SPINDLE WHORLS: A CASE STUDY OF THE LATE ENEOLITHIC SPINDLE WHORLS FROM THE 1C SITE IN GRÓDEK, DISTRICT …
2010
The essential role of yarn spinning in textile production is indisputable. In this context, spindle whorls, the basic spinning accessories that can be found in the archaeological record, are commonly discussed. Even though the importance of the technical specification of spindle whorls has been already recognized by some authors, their functional characteristics are usually limited to the basic parameters affecting their usage range (i.e., weight, diameter and height). And since the mass moment of inertia of spindle whorls is considered to be a salient index when discussing their technical variability, the descriptions are deficient. With this short study, we intend to implement further res…
Outdoor, indoor and personal distribution of BTEX in pregnant women from two areas in Spain - Preliminary results from the INMA project
2010
Volatile organic compounds (VOCs), which are habitually found in both outdoor and indoor environments, may represent a significant health risk. In this context, pregnancy is a critical period since foetuses are more vulnerable than adults to exposure to toxic compounds. The objective of this study is to present the preliminary results of a series of measurements of outdoor (O), indoor (I) and personal exposure (P) to benzene, toluene, ethylbenzene, o-xylene and m,p-xylene (BTEX) in 107 pregnant women from two areas in Spain, namely Valencia and Sabadell. BTEX samplers were installed for 48 hours both inside and outside of the women’s homes, along with personal samplers. In addition, the tes…
Utility of the Mantel-Haenszel Procedure for Detecting Differential Item Functioning in Small Samples
2004
Sample-size restrictions limit the contingency table approaches based on asymptotic distributions, such as the Mantel-Haenszel (MH) procedure, for detecting differential item functioning (DIF) in many practical applications. Within this framework, the present study investigated the power and Type I error performance of empirical and inferential criteria for DIF detection in small samples. Sample sizes (50/50, 100/50, 200/50, and 100/100 for the reference and focal groups, respectively), ability distributions (equal and unequal), and amount of DIF (moderate and high) were manipulated. The results show the advantages of employing theMHchi-square statistic using high levels of significance (•…