Search results for "Determination"

Predicting Coaches' Adherence/Dropout: A Prospective Study

2015

The objective of this study was to examine motivational variables based on self-determination theory (SDT) and positive psychology as predictors of coaches' adherence and dropout. A prospective study was performed using a sample of 286 coaches who were tracked over a two-year period. Initially coaches' motivation and psychological need satisfaction were measured; two years later they were contacted and asked if they were still coaching in their original sport. Those who did not were considered as drop-outs for the current study. Logistic binary regression analyses were performed to analyse predictors of persistence and dropout. Need Satisfaction Index (NSI), perceived competence and percei…

2020

Current debates on online privacy are rooted in liberal theory. Accordingly, privacy is often regarded as a form of freedom from social, economic, and institutional influences. Such a negative perspective on privacy, however, focuses too much on how individuals can be protected or can protect themselves, instead of challenging the necessity of protection itself. In this article, I argue that increasing online privacy literacy not only empowers individuals to achieve (a necessarily limited) form of negative privacy, but has the potential to facilitate a privacy deliberation process in which individuals become agents of social change that could lead to conditions of positive privacy and infor…

Fallzahlplanung in referenzkontrollierten Diagnosestudien

2002

Purpose: A tutorial illustration of a flexible approach to determine the sample size in reference-controlled diagnostic trials. Materials and Methods: Assuming the usual setting of a new diagnostic method to be compared with a reference method, the emphasis is on the sensitivity of the new method in comparison with the reference method, using a binary outcome (positive versus negative) for both methods. Based on the confidence interval of the sensitivity, a simple but flexible procedure for determining the sample size is described, which incorporates clinically interpretable information. The procedure is illustrated by the fictious planning of a trial to assess the diagnostic value of MRI v…

Effect of rapid maxillary expansion on sleep apnea-hypopnea syndrome in growing patients. A meta-analysis.

2019

Background Changes produced in the upper airway after rapid maxillary expansion makes this procedure a therapeutic option for treating sleep apnea-hypopnea syndrome (SAHS) in children. The objective of this systematic review and meta-analysis was to analyze the evidence available for the effects of rapid maxillary expansion (RME) on SAHS, analyzing changes produced in oximetric variables: apnea-hypopnea index (AHI); oxygen saturation (SO2); sleep efficiency (SE), total sleep time (TST), percentage of rapid eye movement (REM) phase; and arousal index (AI). Material and Methods An electronic search was conducted in the PubMed, Scopus, Embase, and Cochrane databases, and in grey literature (Op…

Carbohydrates as Chemical Constituents of Biowaste Composts and their Humic and Fulvic Acids

1995

The decomposition of organic matter of source-separated biowaste during composting was followed during 18 months. Compost samples were fractionated into three parts: (i) hot water soluble extract (HWE) (ii) bitumen fraction and (iii) humic substances (humic acids (HA) and fulvic acids (FA)). Original compost samples and the HA and FA fractions were hydrolyzed with sulfuric acid for hexoses and pentoses. Quantitative spectrophotometric and qualitative GC/MS analyses of monosaccharides as trimethylsilyl ethers of the corresponding alditols were carried out.During composting, the amount of HA in the organic matter of the compost increased, the amounts of HWE and bitumen decreased and the amoun…

Variability of near-surface saturated hydraulic conductivity for the clay soils of a small Sicilian basin

2019

Abstract Proper characterization of saturated hydraulic conductivity, Ks, of clay soils in a hillslope or a basin is still a challenge for soil science. In this investigation, the clay soils of the Maganoce (Sicily, Italy) basin were sampled at 19 sampling sites by the BEST procedure of soil hydraulic characterization. More OM implied less compact conditions (decreasing dry soil bulk density; coefficient of determination, R2 = 0.67), more stability to water of the soil aggregates (increasing water stable aggregates; R2 = 0.83) and, consequently, higher Ks values (R2 = 0.54). Variability of Ks was lower in the steeper zones of the basin than in the flatter ones. A comparison with the Ks data…

Current Bioactive Azole-Containing Natural Products

2010

Complexation of phosphine ligands with peracetylated β-cyclodextrin in supercritical carbon dioxide: spectroscopic determination of equilibrium const…

2007

The interaction between peracetylated beta-cyclodextrin and several triphenyl phosphine derivatives was studied in supercritical carbon dioxide (scCO2) by UV-visible spectroscopy. The equilibrium constant for a 1:1 complexation reaction was obtained from titration spectra and calculated using two established mathematical models. The values of the equilibrium constants are 1-3 orders of magnitude smaller than those obtained in aqueous solution with analogous phosphines. This is likely due to the absence in scCO2 of the hydrophobic effect, which is replaced by a corresponding, but weaker, CO2-phobic effect. The largest value of Kf was found for complexes of diphenyl(4-adamantylphenyl)phosphin…

ARYL-VINYLSULFONE—REAGENTIEN ZUM SCHUTZ UND NACHWEIS VON THIOLFUNKTIONEN

1983

Abstract Aryl vinyl sulfones selectively react with thiol groups to acid-stable compounds which easily are cleaved by mild bases to thiol compounds. Ester and amide groups are not attacked under these conditions. Therefore, these compounds are good protecting groups or labels in peptide chemistry. The following aryl vinyl sulfones were investigated: phenyl vinyl sulfone 1, p-carbethoxyphenyl vinyl sulfone 15 and the fluorescent 5-dimethylaminonaphthyl 1-vinyl sulfone 5 and 5-methoxynaphthyl-1 vinyl sulfone 10. The last two compounds are very useful reagents for the quantitative determination of SH-groups in polypeptides such as enzymes. Aryl-vinylsulfone reagieren selektiv mit Thiolgruppen …

Evidence of the Gluten-Free and Casein-Free Diet in Autism Spectrum Disorders

2014

In autism spectrum disorders, many parents resort to alternative treatments and these are generally perceived as risk free. Among these, the most commonly used is the gluten-free, casein-free diet. The objective of this work was to conduct a systematic review of studies published from 1970 to date related to the gluten-free, casein-free diet in autism spectrum disorder patients. Few studies can be regarded as providing sound scientific evidence since they were blinded randomized controlled trials, and even these were based on small sample sizes, reducing their validity. We observed that the evidence on this topic is currently limited and weak. We recommend that it should be only used after…