Dynamics of the Free Surface of a Conducting Liquid in a Near-Critical Electric Field

Near-critical behavior of the free surface of an ideally conducting liquid in an external electric field is considered. Based on an analysis of three-wave processes using the method of integral estimations, sufficient criteria for hard instability of a planar surface are formulated. It is shown that the higher-order nonlinearities do not saturate the instability, for which reason the growth of disturbances has an explosive character.Comment: 19 page

Assessing socio-economic damage caused by coxarthrosis in the population

Background. About 40 % of patients diagnosed with coxarthrosis annually seek medical help and receive social support due to this disease. Increased use of an expensive surgery for treatment of coxarthrosis and projected growth of its prevalence in the population determine the relevance of socio-economic analysis. The aim of the study. To assess the value and structure of economic damage caused by the delivering health and social care to patients with coxarthrosis at the state level of the Russian Federation. Methods. To assess economic damage, we used the average annual number of various categories of patients and disabled people with coxarthrosis in the Irkutsk region for 2008–2017. Three main categories were identified: patients who visited the outpatients’ clinic; patients with total hip replacement; disabled people due to coxarthrosis. For each category, we calculated weighted average damage per  1  conventional patient, taking into account direct and indirect costs and subsequent multiplication by the average annual number of individual categories of patients. Calculations were performed in 2017 prices. Results. The average annual socio-economic damage from coxarthrosis amounted to 1.39 (1.34÷1.43) billion rubles or 0.1 % of the gross regional product. The most of the damage (64.4 %) were indirect costs associated with disability due to coxarthrosis, 22.2  % of the total amount were the costs of hip replacement surgery, 13.4 % were the costs of outpatient visits. Indirect economic losses due to disability in patients of working age were 4.2 times higher than losses due to disability of oldage pensioners. Conclusion. The results of the study confirm the economic feasibility of surgical treatment of coxarthrosis, especially in patients of working age

PREVALENCE AND STRUCTURAL CHARACTERISTIC OF COXARTHROSIS IN THE UST-ORDYNSK BURYAT DISTRICT

The prevalence of coxarthrosis in Ust-Ordynsk Buryat Region was defined as 19,8 ‰0 This article gives complex characteristics of coxarthrosis in the named region

a direct encoding for nnc polyhedra

We present an alternative Double Description representation for the domain of NNC (not necessarily closed) polyhedra, together with the corresponding Chernikova-like conversion procedure. The representation uses no slack variable at all and provides a solution to a few technical issues caused by the encoding of an NNC polyhedron as a closed polyhedron in a higher dimension space. A preliminary experimental evaluation shows that the new conversion algorithm is able to achieve significant efficiency improvements

Metaproteomics and metabolomics analyses of chronically petroleum-polluted sites reveal the importance of general anaerobic processes uncoupled with degradation

Crude oil is one of the most important natural assets for humankind, yet it is a major environmental pollutant, notably in marine environments. One of the largest crude oil polluted areas in the word is the semi-enclosed Mediterranean Sea, in which the metabolic potential of indigenous microbial populations towards the large-scale chronic pollution is yet to be defined, particularly in anaerobic and micro-aerophilic sites. Here, we provide an insight into the microbial metabolism in sediments from three chronically polluted marine sites along the coastline of Italy: the Priolo oil terminal/refinery site (near Siracuse, Sicily), harbour of Messina (Sicily) and shipwreck of MT Haven (near Genoa). Using shotgun metaproteomics and community metabolomics approaches, the presence of 651 microbial proteins and 4776 metabolite mass features have been detected in these three environments, revealing a high metabolic heterogeneity between the investigated sites. The proteomes displayed the prevalence of anaerobic metabolisms that were not directly related with petroleum biodegradation, indicating that in the absence of oxygen, biodegradation is significantly suppressed. This suppression was also suggested by examining the metabolome patterns. The proteome analysis further highlighted the metabolic coupling between methylotrophs and sulphate reducers in oxygen-depleted petroleum-polluted sediments

Diversity of hydrolases from hydrothermal vent sediments of the Levante Bay, Vulcano Island (Aeolian archipelago) identified by activity-based metagenomics and biochemical characterization of new esterases and an arabinopyranosidase

A metagenomic fosmid expression library established from environmental DNA (eDNA) from the shallow hot vent sediment sample collected from the Levante Bay, Vulcano Island (Aeolian archipelago) was established in Escherichia coli. Using activity-based screening assays, we have assessed 9600 fosmid clones corresponding to approximately 350 Mbp of the cloned eDNA, for the lipases/esterases/lactamases, haloalkane and haloacid dehalogenases, and glycoside hydrolases. Thirty-four positive fosmid clones were selected from the total of 120 positive hits and sequenced to yield ca. 1360 kbp of high-quality assemblies. Fosmid inserts were attributed to the members of ten bacterial phyla, including Proteobacteria, Bacteroidetes, Acidobateria, Firmicutes, Verrucomicrobia, Chloroflexi, Spirochaetes, Thermotogae, Armatimonadetes, and Planctomycetes. Of ca. 200 proteins with high biotechnological potential identified therein, we have characterized in detail three distinct α/β-hydrolases (LIPESV12_9, LIPESV12_24, LIPESV12_26) and one new α-arabinopyranosidase (GLV12_5). All LIPESV12 enzymes revealed distinct substrate specificities tested against 43 structurally diverse esters and 4 p-nitrophenol carboxyl esters. Of 16 different glycosides tested, the GLV12_5 hydrolysed only p-nitrophenol-α-(L)-arabinopyranose with a high specific activity of about 2.7 kU/mg protein. Most of the α/β-hydrolases were thermophilic and revealed a high tolerance to, and high activities in the presence of, numerous heavy metal ions. Among them, the LIPESV12_24 was the best temperature-adapted, retaining its activity after 40 min of incubation at 90 °C. Furthermore, enzymes were active in organic solvents (e.g., >30% methanol). Both LIPESV12_24 and LIPESV12_26 had the GXSXG pentapeptides and the catalytic triads Ser-Asp-His typical to the representatives of carboxylesterases of EC 3.1.1.1

Leakage Currents Mechanism in Thin Films of Ferroelectric Hf 0.5 Zr 0.5 O 2

We study the charge transport mechanism in ferroelectric Hf 0.5 Zr 0.5 O 2 thin films. Transport properties of the leakage currents in Hf 0.5 Zr 0.5 O 2 are described by phonon-assisted tunneling between traps. Comparison with transport properties of amorphous Hf 0.5 Zr 0.5 O 2 demonstrates that the transport mechanism does not depend on the crystal structure. The thermal trap energy of 1.25 eV and optical trap energy of 2.5 eV in Hf 0.5 Zr 0.5 O 2 were determined based on comparison of experimentally measured data on transport with simulations within phonon-assisted tunneling between traps in dielectric films. We found that the trap density in ferroelectric Hf 0.5 Zr 0.5 O 2 is slightly less that one in amorphous Hf 0.5 Zr 0.5 O 2 . A hypothesis that oxygen vacancies are responsible for the charge transport in Hf 0.5 Zr 0.5 O 2 is confirmed by electronic structure ab initio simulation

What do we teach when we teach the Learning Sciences? A document analysis of 75 graduate programs

The learning sciences, as an academic community investigating human learning, emerged more than 30 years ago. Since then, graduate learning sciences programs have been established worldwide. Little is currently known, however, about their disciplinary backgrounds and the topics and research methods they address. In this document analysis of the websites of 75 international graduate learning sciences programs, we examine central concepts and research methods across institutions, compare the programs, and assess the homogeneity of different subgroups. Results reveal that the concepts addressed most frequently were real-world learning in formal and informal contexts, designing learning environments, cognition and metacognition, and using technology to support learning. Among research methods, design-based research (DBR), discourse and dialog analyses, and basic statistics stand out. Results show substantial differences between programs, yet programs focusing on DBR show the greatest similarity regarding the other concepts and methods they teach. Interpreting the similarity of the graduate programs using a community of practice perspective, there is a set of relatively coherent programs at the core of the learning sciences, pointing to the emergence of a discipline, and a variety of multidisciplinary and more heterogeneous programs “orbiting” the core in the periphery, shaping and innovating the field