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ABSTRACTSurrogate measures are becoming increasingly used to measure suspended sediment flux, but only few particular computer techniques of data processing are recently developed. This study demonstrates capabilities of acoustic Doppler current profilers (ADCPs) to infer information regarding suspended-sand concentrations in river systems and calculate suspended sediment flux via big data analytics which includes process of analyzing and data mining of measurements based on ADCP signal backscatter intensity data. We present here specific codes done by R language using RStudio software with open-source tidyverse and plotly packages aimed to generate tables containing data of suspended load for cells, verticals and whole cross-section based on backscattering values from 600 kH Teledyne RDInstruments RioGrande WorkHorse ADCP unit, as well perform estimates of morphometric, suspended sediment concentration (SSC) and velocity characteristics of the flow. The developed tools enabled to process large data array consisting of over 56,526,480 geo-referenced values of river depth, streamflow velocity, and backscatter intensity for each river cross-section measured at six case study sites in Russia.

Background: After the Chernobyl nuclear power plant accident in April 1986, a large increase in the incidence of childhood thyroid cancer was reported in contaminated areas. Most of the radiation exposure to the thyroid was from iodine isotopes, especially 131 I. We carried out a population-based case-control study of thyroid cancer in Belarus and the Russian Federation to evaluate the risk of thyroid cancer after exposure to radioactive iodine in childhood and to investigate environmental and host factors that may modify this risk. Methods: We studied 276 case patients with thyroid cancer through 1998 and 1300 matched control subjects, all aged younger than 15 years at the time of the accident. Individual doses were estimated for each subject based on their whereabouts and dietary habits at the time of the accident and in following days, weeks, and years; their likely stable iodine status at the time of the accident was also evaluated. Data were analyzed by conditional logistic regression using several different models. All statistical tests were two-sided. Results: A strong dose-response relationship was observed between radiation dose to the thyroid received in childhood and thyroid cancer risk (P

Communicated by Ramaswamy H. Sarma

This article presents a comparison of laser sintering of deposited nanoparticles obtained by two methods of aerosol jet printing. The first printing method was based on the use of silver nanoparticles in the form of microdroplets contained in nanoink. In the second method, dry nanoparticles were obtained as a result of gas-discharge synthesis without the use of solvents. The nanoparticles in both experiments were deposited on a glass substrate in the form of a line with a width of about 50 ± 5 μm and a height of about 1.0 ± 0.2 μm. Then, the obtained lines were sintered using laser radiation with a wavelength of 1064 nm. As a result of experiments on the deposition and sintering, it was found that the electrical resistivity of the lines of sintered nanoparticles in the form of nanoink and dry nanoparticles obtained in a gas discharge was 8.1 and 4.9 μΩ·cm, respectively. Thus, it has been demonstrated that laser sintering of nanoparticles obtained in a gas discharge makes it possible to achieve a lower specific resistance of lines than the method of aerosol printing using nanoink. In addition, the electrical resistivity of the lines of sintered nanoparticles obtained in a gas discharge is 3 times greater than the electrical resistivity of bulk silver, which is a sufficient result for the creation of conductive elements of printed electronics.

This article presents a study and comparison of two sintering processes of aerosol nanoparticles in process of aerosol jet printing. Silver lines were deposited on glass and plastic substrates. Then obtained lines were sintered in two ways, specifically, thermal and electric methods. As a result of experiments, it was found that during the deposition process, the width of printed lines, with the same printing parameters, is in the range from 92.3 to 110.4 μm and the height from 1.1 to 1.4 μm. The resistivity of lines on the glass substrate, sintered in two ways, is approximately 12 μΩ·cm. While the resistivity of the lines on the plastic substrate, sintered by electric and thermal methods, is 11.1 and 17.2 μΩ·cm, respectively. Thus, electrical sintering allows one to achieve a smaller (by a factor of 1.5) electrical resistivity of lines on a plastic substrate than thermal sintering, which makes it possible to obtain conductive flexible structures with better characteristics.

We present a suite of three workbooks implementing different methods and levels of approximations of quantum chemistry for elements from hydrogen to beryllium: two variants of Hartree–Fock (HF) of increasing complexity and the local spin-density approximation (LSDA) of density functional theory (DFT). Hydrogen-like basis functions for the 1s and 2s orbitals have been chosen, with associated effective charges treated as adjustable parameters. Instead of solving self-consistent equations, the total energy is minimized directly with respect to the orbital effective charges with the aid of the Solver add-in of Excel or by means of the virial theorem. The workbooks provide interactive input of the spin occupations of 1s and 2s orbitals, thus allowing calculation of the total energy not only of the ground-state neutral atoms but also of the first excited singlet and triplet states of helium and helium-like atoms, of the hydrogen anion H–(hydride), and of the lithium and beryllium cations. The calculated total energies are compatible with those obtained by elaborated general-purpose quantum chemistry programs. The workbooks are suitable for upper-division undergraduates or postgraduate students with no previous programming experience. They are open for upgrade and could be used for different forms of computer-based learning in the frame of classroom activities or coursework assignments. The educational outcomes of using spreadsheets in the teaching environment have been quantified by means of Hake’s normalized gain analysis.

In this article, a study is presented of the effect of the focusing ratio (FR) on the line geometry in aerosol printing process. The FR was defined as the ratio of sheath flow to aerosol flow. The FR was varied from 1 to 20. In the experiment, different nozzles were used, with outlet diameter of 100, 150 and 300 μm. It was established that in increasing FR from 1 to 20 by reducing the aerosol flow with constant sheath flow rate, line width and thickness are reduced in more than 40 and 10 times respectively. It is also found that by increasing the FR from 2 to 8 by changing only sheath flow with constant aerosol flow rate, line width is reduced from 125 to 75 μm, while line thickness is increased from 7.1 to 10.3 μm. It is shown that this feature is related to the quantity of the matter deposited on the substrate, which is directly related to aerosol flow. The achieved result is important for designing current-carrying lines of electronic circuits which require a specific aspect ratio and high circuit element density

Polyaniline (PANI) films were prepared by electrochemical polymerization of aniline on Pt-electrode in aqueous medium in the presence of polymeric sulfonic acids distinguished by different flexibility of the polymer chain: (1) poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA, flexible chain); (2) poly(4-styrenesulfonic acid) (PSSA, flexible chain), (3) poly-4,4'-(2,2'-disulfoacid)-diphenylene-iso-phthalamide (i-PASA, semi-rigid chain); and (4) poly-4,4'-(2,2'-disulfoacid)-diphelylene-tere-phthalamide (t-PASA, rigid chain). Raman spectroelectrochemical studies using 532 nm laser excitation were carried out in aqueous HCl. The conventional HCl-doped PANI films were also studied for comparison. The results allowed one to distinguish the potential-dependent vibrations belonging to PANI and potential-independent vibrations belonging to the polyacids. In addition, amide C=O vibration was separated in the spectra by comparing the results for amide-containing (PAMPSA, i-PASA, and t-PASA) and amide-free (PSSA) PANI-polyacid complexes. The films of PANI-polyacid complexes demonstrated increased content of radical cation moieties at low potentials compared to PANI–HCl films.

We have developed an aerosol-based technique for deposition of monodisperse ensembles of spherical SiO2 nanoparticles on the surface of single-crystal silicon substrate (1 cm2) with an average surface particle density of about 2.1±0.4 particles per μm2. The obtained samples of monodisperse ensembles SiO2 nanoparticles was characterized by scanning and transmission electron microscopy. The ensemble of deposited nanoparticles is characterized by a narrow size distribution with a modal size of 26.6 nm and a full width at half maximum of 3.5 nm according to the atomic force microscopy data. We have demonstrated the use of the obtained test structure to determine the effective radius of the tip of an atomic force microscope.

ObjectiveTo systematically review and perform a meta-analysis of radiation associated risks of cardiovascular disease in all groups exposed to radiation with individual radiation dose estimates.DesignSystematic review and meta-analysis.Main outcome measuresExcess relative risk per unit dose (Gy), estimated by restricted maximum likelihood methods.Data sourcesPubMed and Medline, Embase, Scopus, Web of Science Core collection databases.Eligibility criteria for selecting studiesDatabases were searched on 6 October 2022, with no limits on date of publication or language. Animal studies and studies without an abstract were excluded.ResultsThe meta-analysis yielded 93 relevant studies. Relative risk per Gy increased for all cardiovascular disease (excess relative risk per Gy of 0.11 (95% confidence interval 0.08 to 0.14)) and for the four major subtypes of cardiovascular disease (ischaemic heart disease, other heart disease, cerebrovascular disease, all other cardiovascular disease). However, interstudy heterogeneity was noted (P<0.05 for all endpoints except for other heart disease), possibly resulting from interstudy variation in unmeasured confounders or effect modifiers, which is markedly reduced if attention is restricted to higher quality studies or those at moderate doses (<0.5 Gy) or low dose rates (<5 mGy/h). For ischaemic heart disease and all cardiovascular disease, risks were larger per unit dose for lower dose (inverse dose effect) and for fractionated exposures (inverse dose fractionation effect). Population based excess absolute risks are estimated for a number of national populations (Canada, England and Wales, France, Germany, Japan, USA) and range from 2.33% per Gy (95% confidence interval 1.69% to 2.98%) for England and Wales to 3.66% per Gy (2.65% to 4.68%) for Germany, largely reflecting the underlying rates of cardiovascular disease mortality in these populations. Estimated risk of mortality from cardiovascular disease are generally dominated by cerebrovascular disease (around 0.94-1.26% per Gy), with the next largest contribution from ischaemic heart disease (around 0.30-1.20% per Gy).ConclusionsResults provide evidence supporting a causal association between radiation exposure and cardiovascular disease at high dose, and to a lesser extent at low dose, with some indications of differences in risk between acute and chronic exposures, which require further investigation. The observed heterogeneity complicates a causal interpretation of these findings, although this heterogeneity is much reduced if only higher quality studies or those at moderate doses or low dose rates are considered. Studies are needed to assess in more detail modifications of radiation effect by lifestyle and medical risk factors.Systematic review registrationPROSPERO CRD42020202036

This paper presents a resonance Raman spectroscopy study of ∼1 nm diameter HgTe nanowires formed inside single walled carbon nanotubes by melt infiltration. Raman spectra have been measured for ensembles of bundled filled tubes, produced using tubes from two separate sources, for excitation photon energies in the ranges 3.39–2.61 and 1.82–1.26 eV for Raman shifts down to ∼25 cm–1. We also present HRTEM characterization of the tubes and the results of DFT calculations of the phonon and electronic dispersion relations, and the optical absorption spectrum based upon the observed structure of the HgTe nanowires. All of the evidence supports the hypothesis that the observed Raman features are not attributable to single walled carbon nanotubes, i.e., peaks due to radial breathing mode phonons, but are due to the HgTe nanowires. The observed additional features are due to four distinct phonons, with energies 47, 51, 94, and 115 cm–1, respectively, plus their overtones and combinations. All of these modes have strong photon energy resonances that maximize at around 1.76 eV energy with respect to incident laser.

An excerpt from the speech of the head of the Federal Drug Control Service of Russia, Victor Ivanov, at an international experts conference held on March 25, 2014 in Moscow, Russia is presented.

Polyaniline (PANI) was synthesized by chemical oxidation of aniline in the presence of mixtures of water-soluble poly(sulfonic acids) of different nature. Under these conditions, the use of polyacid templates leads to the formation of interpolymer complexes of PANI and polyacid mixtures. The obtained PANI complexes were characterized by UV, visible, near IR, and Fourier transform infrared spectroscopy. It was shown that the rigidity of the polyacid backbone and the composition of a polyacid mixture affect the electronic structure of PANI complexes and the duration of the induction period of aniline oxidation. Domination of the more rigid-backbone template in the synthesis of PANI complexes with mixtures of the rigid- and flexible-backbone polyacids was observed. According to the viscometry and FTIR spectroscopic data, the reason of the domination is the existence of the intermolecular interaction between the polyacids in the mixture. In this case, duration of the induction period of aniline oxidation was between these values for pure polyacids.

The method of electrochemical extraction of oxygen from air employing a solid oxide electrolyte (SOE) is presented. The prototype of electrochemical oxygen generator (pump) for medical applications has been developed and fabricated. It is based on thin-walled tubular segments of YSZ electrolyte (170 μm) with LSM based electrodes (~20 μm). Different technologies: nanopowder production by laser ablation, casting of polymer-ceramic tapes, formation of electrodes-electrolyte green structures by radial magnetic pulsed compaction followed by cosintering at 1200°C, were used for segments fabrication. The magnetron sputtering method was applied to protect metallic interconnects (Crofer 22 APU) with (Mn-Co)3O4 layer. Presented oxygen generator prototype produced 9 liters of pure oxygen per hour under applied power of 50 W at 800°C. No noble metals were used in construction.

Summary:The properties of a single semiflexible mushroom chain at a plane surface with a long‐ranged attracting potential are studied by means of lattice Monte Carlo computer simulation using the bond fluctuation model, configurational bias algorithm for chain re‐growing and the Wang‐Landau sampling technique. We present the diagram of states in variables temperature Tvs. strength of the adsorption potential, εw, for a quite short semiflexible chain consisting of N= 64 monomer units. The diagram of states consists of the regions of a coil, liquid globule, solid isotropic globule, adsorbed coil and cylinder‐like liquid‐crystalline globule. At low values of the adsorption strength εwthe coil–globule and the subsequent liquid–solid globule transitions are observed upon decreasing temperature below the adsorption transition point. At high values of εwthese two transitions change into a single transition from an adsorbed coil to a cylinder‐like liquid‐crystalline solid globule. We conclude that for a semiflexible chain the presence of a plane attracting surface favors the formation of a globule with internal liquid‐crystalline ordering of bonds.

By means of magnetic pulsed compaction and sintering of weakly aggregated alumina based nanopowders the jet forming nozzle samples for hydroabrasive cutting were fabricated. The ceramics were obtained from pure alumina, as well as from alumina, doped by TiO2, MgO and AlMg. The ceramic properties of the channel surface and the nozzle volume were investigated. It was shown that the samples sintered from AlMg doped Al2O3 powder had the best desired mechanical properties and structural characteristics: relative density ~0.97, channel microhardness – 18-20 GPa, channel surface roughness ~0.7 /m, average crystallite size ~1 /m.

The method of electrochemical extraction of oxygen from air employing a solid oxide electrolyte (SOE) is presented. The prototype of electrochemical oxygen generator (pump) for medical applications has been developed and fabricated. It is based on thin-walled tubular segments of YSZ electrolyte (170 μm) with LSM based electrodes (~20 μm). Different technologies: nanopowder production by laser ablation, casting of polymer-ceramic tapes, formation of electrodes-electrolyte green structures by radial magnetic pulsed compaction followed by cosintering at 1200°C, were used for segments fabrication. The magnetron sputtering method was applied to protect metallic interconnects (Crofer 22 APU) with (Mn-Co)3O4 layer. Presented oxygen generator prototype produced 9 liters of pure oxygen per hour under applied power of 50 W at 800°C. No noble metals were used in construction.

Fabrication of dense YSZ electrolytes and porous LSM cathodes in the shape of tubes using a radial magnetic pulsed compaction of multilayered tubular blanks of powder tapes has been investigated. The tapes were prepared with butyral resin binder. The multilayered blanks were compacted magnetically. Magnetic pressures of 0.2-0.3 GPa in amplitude, sintering temperatures as low as 1100-1300 °C (in air) with holding time of 20-540 min have been used. Cathode tubes of 0.2-1.0 mm thick exhibited the reproducible open porosity up to 45 %. YSZ electrolyte tubes with the wall of 100-450 microns thick had near full relative density, 0.97-0.99, and were characterized with grains of 200-500 nm in size on the average depending on the sintering temperature. The electrochemical cells built up of as-prepared tubular electrolytes and traditional research electrodes were tested under the air-hydrogen fuel cell conditions. The specific output power, 0.6 W cm-2, was realized at temperature of 885 °C.

An influence of aggregation degree of alumina nanopowder and of radial magnetic pulsed compaction conditions on the powder densification and on the density distribution inside compacts has been investigated experimentally. The usage of radial magnetic pulsed compaction allows to compact alumina nanopowders up to high densities at low degree of aggregation. The compacts homogeneity is attained by appropriate compaction pulse duration and by the usage of powder packing prior to compaction until the condition with high local sound speed is achieved.

26 April 2006 marks the 20th anniversary of the Chernobyl accident. On this occasion, the World Health Organization (WHO), within the UN Chernobyl Forum initiative, convened an Expert Group to evaluate the health impacts of Chernobyl. This paper summarises the findings relating to cancer. A dramatic increase in the incidence of thyroid cancer has been observed among those exposed to radioactive iodines in childhood and adolescence in the most contaminated territories. Iodine deficiency may have increased the risk of developing thyroid cancer following exposure to radioactive iodines, while prolonged stable iodine supplementation in the years after exposure may reduce this risk. Although increases in rates of other cancers have been reported, much of these increases appear to be due to other factors, including improvements in registration, reporting and diagnosis. Studies are few, however, and have methodological limitations. Further, because most radiation-related solid cancers continue to occur decades after exposure and because only 20 years have passed since the accident, it is too early to evaluate the full radiological impact of the accident. Apart from the large increase in thyroid cancer incidence in young people, there are at present no clearly demonstrated radiation-related increases in cancer risk. This should not, however, be interpreted to mean that no increase has in fact occurred: based on the experience of other populations exposed to ionising radiation, a small increase in the relative risk of cancer is expected, even at the low to moderate doses received. Although it is expected that epidemiological studies will have difficulty identifying such a risk, it may nevertheless translate into a substantial number of radiation-related cancer cases in the future, given the very large number of individuals exposed.

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Magnetic Pulse Compaction (MPC), as a dynamic compaction, can be possible to reach higher relative density of nano metallic compacts owing to sufficiently high pressure and adiabatic heating in very short duration of an order of µsec. The present work is concerned with the magnetic pulsed compaction of the nano-sized aluminum powders, which particle size was a range of 50 ~ 100 nm passivated in air. The compaction pressure was 1.5 GPa for 300 µsec in the temperature range from 20°C to 500°C. The grain size of compacts was maintained less than 50 nm, which was analyzed by X-ray diffraction (XRD) using Scherrer method. From the calculation of adiabatic heat and of pressure induced by thermal expansion, and the observation by transmission electron microscopy (TEM), it was found that Al2O3 could be broken and dispersed with a few nano-meter sizes in the Al matrix and that the ultra fine and uniform bulk structure was maintained up to 400°C of compaction temperature.e

This paper discusses the results of the analysis of the relationship between dose and solid cancer incidence among nuclear workers (males) who worked as liquidators after the Chernobyl accident. Information on this cohort of individuals is available at the regional center of Russian National Medical and Dosimetric Registry operating at the RF State Research Centre-Institute of Biophysics. Medical and dosimetric information on 8,654 persons 18-60 years of age with documented external radiation doses is used for the analysis. These data were gathered in the period from 1996 to 2001 and cover a total of 45,166.5 follow-up person-years. In the cohort under study, 179 solid cancers occurred during this period. The average age of liquidators at the time of exposure was 35.8 years, and the average dose as a result of the Chernobyl exposure was about 0.05 Sv. For an analysis of the dose-effect relationship (induction of radiation-induced malignant neoplasms) the statistical software EPICURE was used. The results of the analysis show that the cancer incidence in this cohort does not exceed cancer incidence in relevant age groups of the Russian population. The mean value of SIR for all cancer diseases was 0.88 (0.76, 1.02, 95% CI) for the whole period of follow-up. Risks for the induction of radiation-related cancer diseases were not statistically meaningful. Excess relative risk per 1 Sv was 0.95 (-1.52, 4.49, 95% CI).

We present the modification of the Prigogine-Herman kinetic equation related to the network traffic. We discuss a solution of this equation for homogeneous time-independent situations and for the lognormal desired speed distribution function, obtained from the traffic measurements. This solution clearly shows two modes corresponding to individual flow patterns (low concentration mode) and to collective flow patterns (traffic jam mode). For situations with low concentration, there is almost a linear dependence of the information flow versus the concentration and the higher the average speed the lower the concentration at which the optimum flow takes place. When approaching the critical concentration, there are no essential differences in the flow for different average speeds, whereas for the individual flow regions there are dramatic differences.

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In 1996, following several years of collaborative international studies of the consequences of the Chernobyl accident, a number of groups proposed to carry out case-control studies of thyroid cancer among young people in contaminated territories of Belarus and Russia. Collaborations were set-up between the participants of the Chernobyl Sasakawa Project and of those of the Belarus/Russia/EU/IARC project. These involved joint field work and dose reconstruction, although both projects maintained their original objectives: to evaluate the risk of I-131-induced thyroid cancer and to study the role of possible modifying factors in radiation carcinogenesis, in particular, iodine deficiency and supplementation and genetic predisposition. Joint data collection is now virtually finished and dose reconstruction is nearing completion. Final results are expected in 2002. The current paper summarises the objectives and methods of the case-control studies, as well as the very preliminary results based on joint data collection and analyses. These appear to indicate that cases were likely to have received higher doses from I-131 on average than controls. The collaboration has resulted in the collection of one of the largest sources of data on thyroid cancer risk in children, adolescents and young adults exposed to ionising radiation. Results from this work are likely to have important implications for radiation protection in general, as well as for public health actions among exposed populations in the CIS.

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We present recent data of our Monte Carlo computer simulation study of properties of AB‐copolymer globules which depend strongly on the primary sequence of A and B monomeric units. Different primary sequences have been studied: random, random‐block, regular and designed ones by using some particular spatial conformation of a homopolymer chain (we have compared here three models: proteinlike copolymers, AB‐copolymers modeling membrane proteins and ABC‐copolymers modeling proteins with active enzymatic center). We have found several evidences for the fact that an AB‐copolymer chain with a primary sequence prepared on the basis of a particular conformation of a homopolymer chain by some “coloring” procedure preserves the “memory” about its “parent” spatial conformation. Analyzing the power spectra of AB‐sequences, we find the existence of long‐range power‐law correlations for the copolymers with specially designed primary sequences.

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The development of motorization in many countries has stimulated the growth of car flow in recreational regions. It has exacerbated ecological problems, especially on the sea coast. To deal with this, car flows need regulation at international, national, regional and local levels through planning, organizational and technical measures. This calls for co-operation between countries with coastal resorts. The paper suggests, for example, international consideration of a coastal distributive road (rocade) from the Black Sea to the Adriatic.

The results of this report in certain cases facilitate to answer the following practically urgent question i.e. how much the control efficiency can be increased by optimizing the control algorithms and by using additional initial data. In addition, on the ground of optimal algorithms more efficient technical control devices can be designed.

Effect of the precursor approach, the method of nanosized powders pressing, and the sintering temperature of ceramic samples on the low-field magnetoresistance of nanosized La_0.7Sr_0.3MnO₃ ceramics was studied.

The article presents a speech by Viktor Petrovich Ivanov, head of Russian Federal Drug Control Service (FDCS) with his U.S. counterpart, Director of the Office of National Drug Control Policy Gil Kerlikowske, in public meeting on Drugs and Security held at the Belfer Center of Harvard University on December 14, 2012. He informed that raw drug is produced in few countries such as Afghanistan but transported in various countries. The drug trafficking monetarily benefits the world banking system.

Oxidation of vacuum thermally evaporated thin films of polyaniline by aqueous nitric acid results in autocatalytic formation of filament-like heterogeneous dissipative structures in the oxidized areas due to non-equlibrium reactions between the reduced form of polyaniline and the oxidant.