SAFT-γ force field for the simulation of molecular fluids: 8. hetero-group coarse-grained models of perfluoroalkylalkanes assessed with new vapour-liquid interfacial tension data

The air-liquid interfacial behaviour of linear perfluoroalkylalkanes (PFAAs) is reported through a combined experimental and computer simulation study. The surface tensions of seven liquid PFAAs (perfluorobutylethane, F4H2; perfluorobutylpentane, F4H5; perfluorobutylhexane, F4H6, perfluorobutyloctane, F4H8; perfluorohexylethane, F6H2; perfluorohexylhexane, F6H6; and perfluorohexyloctane, F6H8) are experimentally determined over a wide temperature range (276 to 350 K). The corresponding surface thermodynamic properties and the critical temperatures of the studied compounds are estimated from the temperature dependence of the surface tension. Experimental density and vapour pressure data are employed to parameterize a generic heteronuclear coarse-grained intermolecular potential of the SAFT- γ family for PFAAs. The resulting force field is used in direct molecular dynamics simulations to predict with quantitative agreement the experimental tensions and to explore the conformations of the molecules in the interfacial region revealing a preferential alignment of the PFAA molecules towards the interface and an enrichment of the perfluoro-groups at the outer interface region

Accuracy assessment of primary production models with and without photoinhibition using Ocean Colour Climate Change Initiative data in the North East Atlantic Ocean.

The accuracy of three satellite models of primary production (PP) of varying complexity was assessed against 95 in situ 14C uptake measurements from the North East Atlantic Ocean (NEA). The models were run using the European Space Agency (ESA), Ocean Colour Climate Change Initiative (OC-CCI) version 3.0 data. The objectives of the study were to determine which is the most accurate PP model for the region in different provinces and seasons, what is the accuracy of the models using both high (daily) and low (eight day) temporal resolution OC-CCI data, and whether the performance of the models is improved by implementing a photoinhibition function? The Platt-Sathyendranath primary production model (PPPSM) was the most accurate over all NEA provinces and, specifically, in the Atlantic Arctic province (ARCT) and North Atlantic Drift (NADR) provinces. The implementation of a photoinhibition function in the PPPSM reduced its accuracy, especially at lower range PP. The Vertical Generalized Production Model-VGPM (PPVGPM) tended to over-estimate PP, especially in summer and in the NADR. The accuracy of PPVGPM improved with the implementation of a photoinhibition function in summer. The absorption model of primary production (PPAph), with and without photoinhibition, was the least accurate model for the NEA. Mapped images of each model showed that the PPVGPM was 150% higher in the NADR compared to PPPSM. In the North Atlantic Subtropical Gyre (NAST) province, PPAph was 355% higher than PPPSM, whereas PPVGPM was 215% higher. A sensitivity analysis indicated that chlorophyll-a (Chl a), or the absorption of phytoplankton, at 443 nm (aph (443)) caused the largest error in the estimation of PP, followed by the photosynthetic rate terms and then the irradiance functions used for each model

Composition of powders produced by electrospark dispersion of metal granules in water

The results of experimental studies of metal powders composition produced by electrospark dispersion according to the scheme "metal electrodes - metal granule loading - distilled water" are given in the paper. With a help of X-ray diffraction analysis and other methods, it was found that chemical and phase composition of dispersion products is determined by affinity of metal to oxygen

Increased proteasomal activity supports photoreceptor survival in inherited retinal degeneration

Inherited retinal degenerations, affecting more than 2 million people worldwide, are caused by mutations in over 200 genes. This suggests that the most efficient therapeutic strategies would be mutation independent, i.e., targeting common pathological conditions arising from many disease-causing mutations. Previous studies revealed that one such condition is an insufficiency of the ubiquitin–proteasome system to process misfolded or mistargeted proteins in affected photoreceptor cells. We now report that retinal degeneration in mice can be significantly delayed by increasing photoreceptor proteasomal activity. The largest effect is observed upon overexpression of the 11S proteasome cap subunit, PA28α, which enhanced ubiquitin-independent protein degradation in photoreceptors. Applying this strategy to mice bearing one copy of the P23H rhodopsin mutant, a mutation frequently encountered in human patients, quadruples the number of surviving photoreceptors in the inferior retina of 6-month-old mice. This striking therapeutic effect demonstrates that proteasomes are an attractive target for fighting inherited blindness

Correlation analysis of clinical and medical history records of married couples receiving infertility treatment

Introduction. Despite the availability of general principles and regimens for ovarian stimulation on the assisted reproductive technology (ART) programs, an individual situational modification is required in each specific case.Objective. To optimize the ovarian stimulation protocols on the ART program based on the clinical and medical history records of the married couple.Materials and methods.The clinical and medical history records, as well as the stimulation cycle parameters of 60 married couples were analysed. The married couples enrolled in this study were diagnosed with infertility caused by tubo-peritoneal (44 married couples), male (5 married couples), combined factor (6 married couples), as well as external genital endometriosis combined with a male factor (3 married couples), and tubo-peritoneal factor (2 married couples). All married couples underwent IVF/ICSI procedures under the gonadotropin-releasing hormone antagonist (GnRH-ant) protocol and ovarian stimulation on day 2 or 3 of the menstrual cycle.Results. All married couples were divided into two groups: 38 couples with a negative implantation result and 20 married couples with positive implantation results. The surgical removal of fallopian tubes has been shown to be inversely correlated with the duration of infertility. The use of hCG positively correlates to the ratio of mature oocytes and oocyte-cumulus complexes (OCC) and the onset of pregnancy. A reduced percentage of morphologically healthy sperm with an overall high concentration of sperm in the ejaculate can be interpreted as fertile sperm.Conclusions. During ovarian stimulation on the ART program, special attention should be paid to the duration of stimulation, the types of interventions for triggering final oocyte maturation and the total gonadotropin dose. A differentiated approach to conducting the surgical removal of fallopian tubes is required. The reduced percentage of morphologically healthy sperm with an overall high concentration of sperm in the ejaculate serves as a favourable prognostic factor for the outcome of ART programs

Soluble amyloid beta-containing aggregates are present throughout the brain at early stages of Alzheimer's disease.

Protein aggregation likely plays a key role in the initiation and spreading of Alzheimer's disease pathology through the brain. Soluble aggregates of amyloid beta are believed to play a key role in this process. However, the aggregates present in humans are still poorly characterized due to a lack of suitable methods required for characterizing the low concentration of heterogeneous aggregates present. We have used a variety of biophysical methods to characterize the aggregates present in human Alzheimer's disease brains at Braak stage III. We find soluble amyloid beta-containing aggregates in all regions of the brain up to 200 nm in length, capable of causing an inflammatory response. Rather than aggregates spreading through the brain as disease progresses, it appears that aggregation occurs all over the brain and that different brain regions are at earlier or later stages of the same process, with the later stages causing increased inflammation

The Role of Digital Communications in the Event Management

Статья посвящена анализу роли цифровых коммуникаций в одном из основных инструментов маркетинговых коммуникаций — event-маркетинге.The article analyzes the role of digital communications in one of the main tools of marketing communications — event marketing