Proton exchange membrane water electrolysis with short-side-chain Aquivion membrane and IrO2 anode catalyst

A series of three membrane types has been screened for medium temperature solid polymer electrolyte water electrolysis in membrane electrode assemblies coated with 2 mg cm⁻² of iridium oxide as a catalyst for the oxygen evolution reaction, synthesised via a hydrolysis method from the hexachloroiridic acid precursor, and deposited on the membrane either directly by spray deposition or by decal transfer. The short-side-chain perfluorosulfonic acid Aquivion^® ionomer of equivalent weight 870 meq g⁻¹, in membranes of thickness 120 μm, gives higher water electrolysis performance at 120 °C than a composite membrane of Aquivion^® with zirconium phosphate, while a sulfonated ether-linked polybenzimidazole, sulfonated poly-[(1-(4,4′-diphenylether)-5-oxybenzimidazole)-benzimidazole], shows promising performance and no transport limitations up to 2 A cm⁻². The lowest cell voltage was observed at 120 °C for an MEA prepared using spray-coating directly on the Aquivion^® membrane, 1.57 V at 1 A cm⁻².     

Wall temperature experimental investigation in a thermally driven channel

Direct local wall temperature has been measured, in a steady state, along a vertical air channel asymmetrically heated with uniform fluxes. In the range of high Grashof numbers that was investigated, the flow regime probably remained laminar. A radiative part has been analysed with two extreme values of internal surface emissivity corresponding to unpainted metal and black painted wall. A correlation has been proposed for the calculation of a characteristic channel outlet value of the Nusselt number referred to air spacing. A local Nusselt number over the height has been developed in a power law scheme.     

Circulating Monocyte Subsets and Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR), as an alternative to open heart surgery, has revolutionized the treatment of severe aortic valve stenosis (AVS), the most common valvular disorder in the elderly. AVS is now considered a form of atherosclerosis and, like the latter, partly of inflammatory origin. Patients with high-grade AVS have a highly disturbed blood flow associated with high levels of shear stress. The immediate reopening of the valve during TAVR leads to a sudden restoration of a normal blood flow hemodynamic. Despite its good prognosis for patients, TAVR remains associated with bleeding or thrombotic postprocedural complications, involving mechanisms that are still poorly understood. Many studies report the close link between blood coagulation and inflammation, termed thromboinflammation, including monocytes as a major actor. The TAVR procedure represents a unique opportunity to study the influence of shear stress on human monocytes, key mediators of inflammation and hemostasis processes. The purpose of this study was to conduct a review of the literature to provide a comprehensive overview of the impact of TAVR on monocyte phenotype and subset repartition and the association of these parameters with the clinical outcomes of patients with severe AVS who underwent TAVR.     

CHSPAM: a multi-domain model for sequential pattern discovery and monitoring in contexts histories

Pattern Analysis and Applications - Context-aware applications adapt their functionalities based on users contexts. Complementarily, a context history has information about previous contexts...     

Can dynamic in vitro digestion systems mimic the physiological reality?

During the last decade, there has been a growing interest in understanding the fate of food during digestion in the gastrointestinal tract in order to strengthen the possible effects of food on human health. Ideally, food digestion should be studied in vivo on humans but this is not always ethically and financially possible. Therefore simple static in vitro digestion models mimicking the gastrointestinal tract have been proposed as alternatives to in vivo experiments but these models are quite basic and hardly recreate the complexity of the digestive tract. In contrast, dynamic models that allow pH regulation, flow of the food and injection in real time of digestive enzymes in the different compartments of the gastrointestinal tract are more promising to accurately mimic the digestive process. Most of the systems developed so far have been compared for their performances to in vivo data obtained on animals and/or humans. The objective of this article is to review the validation towards in vivo data of some of the dynamic digestion systems currently available in order to determine what aspects of food digestion they are able to mimic. Eight dynamic digestion systems are presented as well as their validation towards in vivo data. Advantages and limits of each simulator is discussed. This is the result of a cooperative international effort made by some of the scientists involved in Infogest, an international network on food digestion     

High frequency of nonclassical steroid 21-hydroxylase deficiency

Nonclassical steroid 21-hydroxylase deficiency is an autosomal recessive disorder that is defined by clinical and hormonal criteria that distinguishes it from the classical 21-hydroxylase deficiency. No estimates of the gene frequency of nonclassical 21-hydroxylase deficiency, also called attenuated, late-onset, acquired, and cryptic adrenal hyperplasia, have been published thus far. Here, we have used HLA-B genotype data in families containing multiple members affected with nonclassical 21-hydroxylase deficiency together with the results of quantitative hormonal tests to arrive at estimates of gene and disease frequencies for this disorder. We found nonclassical 21-hydroxylase deficiency to be a far more common disorder than classical 21-hydroxylase deficiency, which occurs in 1/8,000 births. The prevalence of the disease in Ashkenazi Jews was 3.7%; in Hispanics, 1.9%; in Yugoslavs, 1.6%; in Italians, 0.3%; and in the diverse Caucasian population, 0.1%. The gene for nonclassical 21-hydroxylase deficiency is in genetic linkage disequilibrium with HLA-B14 in Ashkenazi Jews, Hispanics, and Italians, but not in Yugoslavs or in a diverse, non-Jewish, Caucasian group. The penetrance of nonclassical 21-hydroxylase deficiency gene in the HLA-B14 containing haplotypes was incomplete. Thus, nonclassical 21-hydroxylase deficiency is probably the most frequent autosomal recessive genetic disorder in man and is especially frequent in Ashkenazi Jews, Hispanics, Italians, and Yugoslavs.     

Allergy to extensively hydrolyzed cow milk proteins in infants: identification and treatment with an amino acid-based formula

OBJECTIVE: To evaluate acetowhite changes of the cervix and vulva as a predictor of human papillomavirus (HPV) infection. METHODS: In this population-based study all women aged 19, 21, 23, and 25 years and registered as living in a primary health care area within the city of Ume?, Sweden were eligible for inclusion. Each participant underwent a gynecologic examination with sampling of epithelial cells for HPV-DNA detection and Papanicolaou smear. Colposcopy was performed 5 minutes after application of 5% acetic acid. A two-step polymerase chain reaction (PCR) technique was employed for HPV-DNA detection. RESULTS: Colposcopy and sampling of epithelial cells could be performed in 535 women. The sensitivity of detection of HPV infection by the acetowhitening of the cervix was 22% (95% confidence interval [CI] 18%, 26%). The specificity of detection of HPV infection by the acetowhitening of the cervix was 90% (95% CI 87%, 93%). The sensitivity of detection of HPV infection by cytology was 13% (95% CI 10%, 16%), and the specificity was 99% (95% CI 98%, 100%). The combination of acetowhitening and cytology did not improve the diagnostic value. CONCLUSION: Acetowhitening of the cervix and vulva has low sensitivity as a predictor of HPV infections as determined by PCR.     

Power and sample size calculations for studies involving linear regression

This article presents methods for sample size and power calculations for studies involving linear regression. These approaches are applicable to clinical trials designed to detect a regression slope of a given magnitude or to studies that test whether the slopes or intercepts of two independent regression lines differ by a given amount. The investigator may either specify the values of the independent (x) variable(s) of the regression line(s) or determine them observationally when the study is performed. In the latter case, the investigator must estimate the standard deviation(s) of the independent variable(s). This study gives examples using this method for both experimental and observational study designs. Cohen's method of power calculations for multiple linear regression models is also discussed and contrasted with the methods of this study. We have posted a computer program to perform these and other sample size calculations on the Internet (see http://www.mc.vanderbilt.edu/prevmed/psintro+ ++.htm). This program can determine the sample size needed to detect a specified alternative hypothesis with the required power, the power with which a specific alternative hypothesis can be detected with a given sample size, or the specific alternative hypotheses that can be detected with a given power and sample size. Context-specific help messages available on request make the use of this software largely self-explanatory.     

Dyeing plants screening: an approach to combine past heritage and present development

The paper reports an investigation of the colouring properties of 43 dyeing plants chosen for their widespread use in previous centuries. Colorimetric analysis showed that the principal colours on different fabric supports were yellow and mostly unsaturated. The nature of the support fibres investigated, protein- or cellulose-based, was shown to play an important role in the perceived colours. Phytochemical analysis confirmed that yellow-orange shades could be attributed to flavonoids and that red colours were due to anthraquinones. Colours from plants that contain anthocyanins varied from blue-violet through reddish depending on the structure of the anthocyanins in the individual plants. Colour fastness was determined by applying standard test methods. Fastness to light appeared to be inadequate for industrial applications for most samples, but it seems that this could be improved by certain molecular associations. On the other hand, colour fastness to water was satisfactory.