Tungstate Based Ceramics Obtained By Spark Plasma Sintering Method – Possible Material for Consolidation of Radioactive Wastes’ Components

The Spark Plasma Sintering method was used to produce high-density ceramics from tungstates SrWO4 and NaNd(WO4)2 with scheelite structure. These compounds are proposed as possible matrices for the consolidation of radwaste components. Powder samples were obtained by coprecipitation method and studied by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). After sintering, the samples retained their phase identity (scheelite structure). The total duration of sintering was ∼ 13-15 min, the relative density was reached ∼ 92, 99%. Keywords: Tungstates, RW, Spark Plasma Sintering, high density, microstructur

Widely tunable thermo-optic plasmonic bandpass filter

We report thermally tunable optical bandpass filters based on long-range surface plasmon polariton waveguides. A thin gold stripe in the waveguide core is surrounded by dielectric layers with dissimilar refractive index dispersions and dissimilar thermo-optic coefficients. High filter transmission is achieved for a wavelength at which the refractive indices of the upper and lower cladding layers are identical, and this spectral point may be changed by varying the filter temperature. Experimentally, over 220 nm of bandpass tuning is achieved around 1550 nm wavelength by varying the device temperature from 19 to 27 degrees C. (C) 2013 AIP Publishing LLC.close3

Risk factors for myocardial infarction during carotid endarterectomy in high-risk patients with coronary artery disease

Aim. To determine the value of various risk factors for predicting the myocardial infarction (MI) during carotid endarterectomy in high-risk patients with coronary artery disease (CAD).Material and methods. The single-center cohort prospective study included 204 high-risk patients with CAD who required carotid endarterectomy (CEA). Before surgery, all patients underwent treatment of CAD, and all patients were clinically stabilized. The first step was CEA. Clinical and diagnostic factors associated with the risk of perioperative MI were studied. There were following end points of the study: stroke, MI, death due to MI. The diagnosis of MI was established when there was a combination of an increase in cTn-I troponin above the 99th percentile upper reference limit with electrocardiographic manifestations of myocardial ischemia, or with chest pain or equivalent symptoms consistent with myocardial ischemia.Results. There were no strokes. There were no deaths due to MI. Perioperative MI developed in 8 (3,9%) patients. There were following most significant predictors of perioperative MI: severe impairment of local left ventricular (LV) contractility (hazard ratio (HR), 13,57; 95% confidence interval (CI), 1,427-124,782, p<0,05) and a decrease in left ventricular ejection fraction <50% (HR, 10,909; 95% CI, 1,052-271,229, p<0,05). However, following factors were insignificant for predicting perioperative MI (p>0,05): SYNTAX score, prior cerebrovascular accident, myocardial infarction, insulin-dependent diabetes mellitus, obesity, chronic obstructive pulmonary disease.Conclusion. In high-risk patients with CAD, severe impairment of local LV contractility and global LV systolic dysfunction are the most significant risk factors for perioperative MI during CEA

Obstructive sleep apnea syndrome as an accident risk factor in professional drivers in Yekaterinburg. Dangerous Sleep (DS-1) study

About 20% of all road traffic accidents may be associated with falling asleep while driving. This may be caused by sleep disorders leading to daytime sleepiness, the most common of which is obstructive sleep apnea syndrome (OSAS). Objective: to study somatic and mental health, sleep disorders, OSAS in particular, in the population of Russian drivers (Sverdlovsk Region). Patients and methods. The descriptive cohort «Dangerous Sleep» (DS-1) study of 20 professional drivers having more than 5-year driving experience was conducted at the Clinical Institute of the Brain. The mean age of the drivers was 45.8 years. They underwent somatic evaluation for cardiovascular risk factors and a psychological examination involving a risk readiness diagnostic procedure, the Zung Self-Rating Depression Scale, the Beck Depression Inventory, and an electroencephalographic examination. A somnological examination assumed testing using the Epworth sleepiness scale, polysomnography, or overnight pulse metry. Results and discussion. 30% of the drivers were found to have marked attention disorders and an inability to adapt to extreme conditions, which create a risk for professional duties. The predisposing factors were noted to be alcohol addiction, overweight, and OSAS, the rate of the latter proved to be higher than that in the general population of able-bodied men. It was shown that a somnological examination should be obligatorily performed while hiring professional drivers, particularly to long hauliers. The drivers having a long length of experience, in whom a periodic examination detects sleep disorders, should be treated for somatic diseases and should also have individual working schedules to rule out their long night-time driving

Investigation of the microstructure of the fine-grained YPO4_4:Gd ceramics with xenotime structure after Xe irradiation

The paper reports on the preparation of xenotime-structured ceramics by the Spark Plasma Sintering (SPS) method. Phosphates Y$_{0.95}$Gd$_{0.05}$PO$_4$ (YPO$_4$:Gd) were obtained by the sol-gel method. The synthesized nanopowders are collected in large agglomerates 10-50 mkm in size. Ceramics has a fine-grained microstructure and a high relative density (98.67%). The total time of the SPS process was approximately 18 min. High-density sintered ceramics YPO$_4$:Gd with a xenotime structure were irradiated with Xe$^{+26}$ ions (E = 167 MeV) to fluences of $1\times10^{12}$-$3\times 10^{13}$ cm$^{-2}$. Complete amorphization at maximum fluence was not achieved. As the fluence increases, an insignificant increase in the depth of the amorphous layer is observed. According to the results of grazing incidence XRD (GIXRD), with an increase in fluence from $1\times10^{12}$-$3\times 10^{13}$ cm$^{-2}$, an increase in the volume fraction of the amorphous structure from 20 to 70% is observed. The intensity of XRD peak 200 YPO$_4$:Gd after recovery annealing (700$^\circ$C, 18 h) reached a value of ~80% of the initial intensity I0.Comment: 16 pages, 10 figure

A Novel Combined Term Suggestion Service for Domain-Specific Digital Libraries

Interactive query expansion can assist users during their query formulation process. We conducted a user study with over 4,000 unique visitors and four different design approaches for a search term suggestion service. As a basis for our evaluation we have implemented services which use three different vocabularies: (1) user search terms, (2) terms from a terminology service and (3) thesaurus terms. Additionally, we have created a new combined service which utilizes thesaurus term and terms from a domain-specific search term re-commender. Our results show that the thesaurus-based method clearly is used more often compared to the other single-method implementations. We interpret this as a strong indicator that term suggestion mechanisms should be domain-specific to be close to the user terminology. Our novel combined approach which interconnects a thesaurus service with additional statistical relations out-performed all other implementations. All our observations show that domain-specific vocabulary can support the user in finding alternative concepts and formulating queries.Comment: To be published in Proceedings of Theories and Practice in Digital Libraries (TPDL), 201

Закупка научного оборудования из средств грантов для центров коллективного пользования и уникальных научных установок

This study is devoted to identifying typical problems in the field of scientific equipment procurement in the interests of core shared research facilities and large-scale research facilities and developing approaches to their solution. The paper provides an analysis on the practice of purchasing scientific equipment, conducted on the basis of statistical data obtained from representatives of core shared research facilities and large-scale research facilities that received governmental support in 2019–2021, as well as on the data of a sociological survey. As a result, the hypotheses put forward by the authors about the predominance of foreign-made scientific equipment in the procurement structure, about the decrease in the average cost of purchased equipment in 2019–2021, about the presence of significant unevenness of scientific equipment by subclasses in the procurement structure of scientific equipment, about the presence of similar organizational problems in the field of procurement of scientific equipment. The article suggests a number of approaches to solving the identified problems arising from the formulations of 4 proven hypotheses.Настоящее исследование посвящено выявлению типовых проблем в области организации закупок научного оборудования в интересах центров коллективного пользования и уникальных научных установок, и разработке подходов к их решению. В работе дается анализ практики закупки научного оборудования, проведенный на основе статистических данных, полученных от представителей центров коллективного пользования и уникальных научных установок, получивших государственную поддержку в 2019–2021 гг., а также на данных социологического опроса. В результате нашли свое подтверждение выдвинутые авторами гипотезы о преобладании в структуре закупок научного оборудования иностранного производства, снижении средней стоимости закупленного оборудования в 2019–2021 гг., наличии значимой неравномерности по подклассам научного оборудования в структуре закупок научного оборудования, наличии однотипных проблем организационного характера в области организации закупок научного оборудования. В статье предложен ряд подходов к решению выявленных проблем, вытекающих из формулировок 4 доказанных гипотез

Manifold Modeling of the Beating Heart Motion

Modeling the heart motion has important applications for diagnosis and intervention. We present a new method for modeling the deformation of the myocardium in the cardiac cycle. Our approach is based on manifold learning to build a representation of shape variation across time. We experiment with various manifold types to identify the best manifold method, and with real patient data extracted from cine MRIs. We obtain a representation, common to all subjects, that can discriminate cardiac cycle phases and heart function types

Are luminescent bacteria suitable for online detection and monitoring of toxic compounds in drinking water and its sources?

Biosensors based on luminescent bacteria may be valuable tools to monitor the chemical quality and safety of surface and drinking water. In this review, an overview is presented of the recombinant strains available that harbour the bacterial luciferase genes luxCDABE, and which may be used in an online biosensor for water quality monitoring. Many bacterial strains have been described for the detection of a broad range of toxicity parameters, including DNA damage, protein damage, membrane damage, oxidative stress, organic pollutants, and heavy metals. Most lux strains have sensitivities with detection limits ranging from milligrams per litre to micrograms per litre, usually with higher sensitivities in compound-specific strains. Although the sensitivity of lux strains can be enhanced by various molecular manipulations, most reported detection thresholds are still too high to detect levels of individual contaminants as they occur nowadays in European drinking waters. However, lux strains sensing specific toxic effects have the advantage of being able to respond to mixtures of contaminants inducing the same effect, and thus could be used as a sensor for the sum effect, including the effect of compounds that are as yet not identified by chemical analysis. An evaluation of the suitability of lux strains for monitoring surface and drinking water is therefore provided