Development and research characteristics of digital shortwave transceiver

The results of research and development on the SDR (software defined radio) transceiver using direct analogue-digital conversion in the receiver and digital signal conditioning at the transmitter. Algorithms for signal generation and processing them at the receiving end are implemented in FPGA type XC7k325T (Xilinx).Experimental research has shown high quality transceiver sensitivity characteristics of selectivity for all types of noise and spurious. It found a number of features in the noise performance of the main elements of the transceiver: an analog- digital converter (LTC 2208) and a digital signal generator (AD9957).Представлены результаты разработки и исследования трансивера по технологии SDR (программно определяемое радио) с прямым аналого-цифровым преобразованием в приемнике и цифровым формированием сигналов в передатчике. Алгоритмы формирования сигналов и обработки их на приемной стороне реализованы в ПЛИС типа XC7k325T (Xilinx). Экспериментальное исследование трансивера показало высокое качество характеристик по чувствительности, избирательности по всем видам помех и побочным излучениям. Обнаружен ряд особенностей в шумовых характеристиках основных элементов трансивера: аналого-цифрового преобразователя (LTC 2208) и цифрового формирователя сигналов (AD9957)

Polymorphism of apolipoprotein A1 gene and lipid profile of blood serum in the Evenki and Buryat populations

The prevalence of genotypes and alleles of polymorphic markers (-75)G>A and (+83)C>T apolipoprotein A1 gene (ApOAl) in samples of ethnic groups from Eastern Siberia (the Evenkis and Buryats) were studied. In the Evenki population allele (-75)A was registered in 22,7 % cases, in the Buryat population - in 22,4 % cases. In the Evenki population allele (+83)T was found in 6,3 % cases, in the Buryat population - in 5,9 % cases. Statistically significant differences of genotypes and alleles APOA1 prevalence between the Evenkis and the Buryats was not found. The prevalence of alleles (-75)G>A and (+83)C>T of gene APOA1 obtained in the study were compared with the prevalence in different populations around the world. For each teenager in the study group we conducted a biochemical analysis of serum lipid profile. Also a comparative analysis of blood lipid profile in carriers of different genotypes was carried out. Comparative analysis of blood lipid profile in carriers of different genotypes was conducted

Chikungunya vaccines: advances in the development and prospects for marketing approval

Chikungunya fever is an acute infectious disease caused by the mosquito-borne Chikungunya virus (CHIKV). In the last decades, cases of the disease have been reported in more than 100 countries; therefore, CHIKV presents a global public health problem. CHIKV genotypes have limited antigenic diversity, and documented reinfection is very rare. Hence, a vaccine could prevent infection and potential disability, as well as reduce the epidemic spread of CHIKV in the population.The aim of the study was to review approaches to the development of preventive vaccines against CHIKV, evaluate promising vaccine candidates in preclinical or clinical development stages, and analyse perspectives and challenges of bringing these vaccines to the pharmaceutical market.According to the literature reviewed, both traditional and modern platforms are used in the development of CHIKV vaccines, which has been ongoing for several decades. Each platform has its advantages and limitations. The most popular platforms are live attenuated vaccines and vaccines with viral vector constructs. To date, about 25 vaccine candidates have successfully passed through preclinical studies, and more than 7 vaccine candidates have progressed to various phases of clinical studies. The preventive medicinal products that have reached the clinical development stage include 4 live attenuated vaccines, 1 inactivated vaccine, 1 vaccine containing virus-like particles, and 1 mRNA vaccine. All 7 candidates have demonstrated cross-protection against multiple genotypes of CHIKV at the level of either preclinical in vivo studies and/or clinical in vitro studies. The research continues, and this shows that not only the scientific community but also health systems are interested in bringing effective CHIKV vaccines to the pharmaceutical market

Analysis of pneumococcal serotypes distribution to determine a model composition for a Russian pneumococcal conjugate vaccine

Diseases caused by Streptococcus pneumoniae, as well as antibiotic resistance of its serotypes, are the leading cause of death amongst children worldwide. To prevent pneumococcal infection, the population is immunised with conjugate vaccines containing different amounts of polysaccharides of certain serotypes. Development of a full-cycle Russian vaccine is vital because the active pharmaceutical ingredients for the vaccines registered in the Russian Federation are produced abroad, and only the final stages of production of vaccines of this group are performed in the territory of the Russian Federation. Considering the phenomenon of serotype replacement associated with the long-term widespread use of pneumococcal conjugate vaccines, it is necessary to carefully select the serotype composition for the new vaccine. The aim of this work was to analyse the serotype distribution of pneumococci in the Russian Federation and other countries in order to select optimal serotypes for the Russian vaccine for human use, taking into account vaccination schedules for each age group. This review presents an analysis of the pneumococcal serotype distribution in the Russian Federation in the pre-vaccination era, as well as after the introduction of routine vaccination. In addition, the review includes data on the serotype distribution in the Eurasian Economic Union countries. The authors described a model composition containing at least sixteen serotypes. It will increase effectiveness of immune protection of the population, providing a more complete coverage of serotypes, considering their prevalence in the Russian Federation. Based on the analysis, the serotype composition for the sixteen-valent pneumococcal conjugate vaccine is proposed for further production and preclinical and clinical trials. A new Russian pneumococcal conjugate vaccine will ensure vaccination of all population groups within the National Immunisation Schedule of the Russian Federation

Estimated Inpatient Hospital Stay in Individual Wards: Guidelines on Radiation Safety after Radioiodine Therapy

Radionuclide therapy safety requirements are regulated by the Russian Radiation Safety Standards (RRSS), which state the maximum allowed radionuclide activity in the body and the equivalent dose rate (EDR) of gamma radiation. Therefore, it is necessary to estimate the time of an inpatient hospital stay in specially designed radionuclide therapy wards. The article presents the findings of individual 131I biokinetics studies in 64 patients admitted to radioiodine therapy of thyrotoxicosis and differentiated thyroid cancer. We developed a method to calculate the time interval to reach the EDR of 20μSv/h and the recommended EDR of 3 and 0.3μSv/h for adults and children, respectively. It is based on the measurement of the 131I excretion constant. Keywords: Radioiodine therapy, Radiation safety, Guidelin

The effect of irradiation on the magnetic properties of rock and synthetic samples: Implications to irradiation of extraterrestrial materials in space

© 2015, Pleiades Publishing, Ltd. We report here the results of laboratory analog experiments to consider the potential effects of solar energetic particles (SEP or solar-flare-associated particles) and galactic cosmic rays (GCR) on the magnetic properties of extraterrestrial materials. We carried out proton bombardment experiments (with irradiation energies E1=400, E2 =850 keV and three irradiation fluences in 1014–1016p/cm2 range) and lead-ion bombardment experiments (E =1 GeV) on (previously demagnetized by 120 mT alternating magnetic field) rock and synthetic samples with the following magnetic carriers: metallic iron and nickel iron, Ti-rich and Ti-free magnetite, pyrrhotite. Irradiation experiments resulted in either further demagnetization or magnetization of irradiated samples depending on the type of magnetic mineralogy and type of ionizing radiation involved. Apart for the formation of radiation-induced remanent magnetization (RIRM), we observed major changes in bulk magnetic properties, i.e., a moderate to dramatic decrease (up to 93%) in the coercivity of remanence Bcr for all iron-bearing phases (iron-in-epoxy and Bensour meteorite samples). Contrary to iron-bearing samples, several magnetite-bearing samples experienced a radiation-induced magnetic hardening (increase in Bcr). Magnetic hardening was also observed for Ar2+ ion-irradiated nickel iron-bearing HED meteorites, measured for comparison with the previously stated results. Therefore, the combined effect of SEP with GCR may magnetically soften iron-bearing materials and harden magnetite-bearing materials. In order to answer the question wether RIRM may account for natural remanent magnetization of meteorites and lunar samples, physical mechanism of RIRM formation and potential dependence of RIRM intensity on the background magnetic field present during irradiation event should be investigated

Heart failure and diabetes mellitus: insight into comorbidity

Diabetes mellitus (DM) and heart failure (HF) are frequent comorbidities with a bidirectional relationship. Patients with HF have increased risk of developing DM, and those with DM are at greater risk of developing HF. HF does not fit clearly into the microangiopathy and macroangiopathy groups. It is known that coronary artery disease and arterial hypertension are the major causes of HF; however, it has been shown that DM can trigger functional and structural abnormalities in the myocardium via diabetic cardiomyopathy, a condition with either restrictive or dilated phenotype. While HF treatment is equally effective and safe in patients with and without DM, this statement is not applicable for antidiabetic treatment. Several antidiabetic drugs, such as rosiglitazone, pioglitazone and saxagliptin increase the risk of hospitalisation for HF, therefore these antidiabetic drugs are contraindicated in patients with DM and HF or patients at risk of developing HF. Despite a large number of clinical evidence, uncertainty about the safety of antidiabetic drugs in patients with HF always exists. In this review, the issues of DM treatment in patients with HF are addressed in detail