Evaluation of the PV cell operation temperature in the process of fast switching to open-circuit mode

A procedure for measuring the overheating temperature (ΔT ) of a p-n junction area in the structure of photovoltaic (PV) cells converting laser or solar radiations relative to the ambient temperature has been proposed for the conditions of connecting to an electric load. The basis of the procedure is the measurement of the open-circuit voltage (VO C ) during the initial time period after the fast disconnection of the external resistive load. The simultaneous temperature control on an external heated part of a PV module gives the means for determining the value of VO C at ambient temperature. Comparing it with that measured after switching OFF the load makes the calculation of ΔT possible. Calibration data on the VO C = f(T ) dependences for single-junction AlGaAs/GaAs and triple-junction InGaP/GaAs/Ge PV cells are presented. The temperature dynamics in the PV cells has been determined under flash illumination and during fast commutation of the load. Temperature measurements were taken in two cases: converting continuous laser power by single-junction cells and converting solar power by triple-junction cells operating in the concentrator modules

Overview of Hantavirus Infections in the World, the Epidemiological Situation on Hemorrhagic Fever with Renal Syndrome in the Russian Federation in 2021, and Forecast for 2022

The paper presents a description of the epidemiological situation on Hantavirus infection incidence in the countries around the world. Comparative analysis of the intensity and dynamics of the epidemiological process of hemorrhagic fever with renal syndrome (HFRS) in the Russian Federation by Federal Districts in 2021 has been carried out and forecast of the HFRS incidence for 2022 prepared. The study has revealed that tense situation on incidence of hantavirus diseases was observed in the world in 2021. On the territory of the Russian Federation, there was a decrease in the HFRS incidence in 2021 (by 1.7 times compared to 2020). However, the results of epidemiological analysis of the HFRS incidence, epizootiological data and laboratory studies in certain Federal Districts of the Russian Federation indicate that the epidemiological situation on HFRS remains tense. High risk of HFRS infection is predicted in a number of regions of the country due to the favorable natural and climatic conditions in the winter period of 2021–2022 with a heavy snow cover, which contributed to the under-snow reproduction of small mammals, the main carriers of HFRS. The presence of infected rodents testifies to a high likelihood of complication of the epidemiological situation in areas of increased epidemic risk of HFRS

Progress in developing HCPV modules of SMALFOC-design Progress In Developing HCPV Modules Of SMALFOC-Design

Abstract: This work presents a module generation which has been named as "SMALFOC module design". The abbreviation reflects the main features of the modules: Small-size concentrators; Multi-junction cells; "All-glass" structure; Lamination technology; Fresnel Optics for Concentration. Investigated modules have revealed a quite low over-heating temperature of cells in the MPP regime of operation and a real way for increasing the PV efficiency, if the rear glass base is supplied with an antireflection coating. Outdoor and high/low temperature tests have shown a good potential for long-term operation of such a type of modules

VIRULENCE AND ANTIBIOTIC RESISTANCE OF ISOLATES OF KLEBSIELLA PNEUMONIAE IN NEWBORNS WITH LOCALIZED AND GENERALIZED FORMS OF INFECTION

Objective. To study the effect of virulence and antibiotic sensitivity of K. pneumoniae on the course and outcome of localized and generalized forms of infection in newborns.The authors studied 25 samples of K. pneumoniae isolated from the blood (12 isolates) and feces (13 isolates) of the children with various forms of neonatal infection. Group 1 consisted of 12 children with bacteriologically proven neonatal sepsis, K. pneumoniae was isolated of their blood. Group 2 included 13 children with localized bacterial infection in the form of pneumonia, K. pneumoniae was isolated from their feces. The PCR method was used to determine the virulence factors of the isolates of K. pneumoniae-rmpA, aerobactin and colibactin. The sensitivity of K. pneumoniae to antibiotics was determined by the Kirby-Bauer method. The double disk method was used to determine the ability of K. pneumoniae to produce extended-spectrum β-lactamases (ESBL).Results. In Group 1 the isolates of K. pneumoniae produced ESBL in 8 children out of 12. The bacteria were sensitive to meropenem, amikacin and ciprofloxacin in 4 cases. One child demonstrated resistance to meropenem. The remaining 4 isolates were sensitive to the third-generation cephalosporins protected by aminopenicillins, amikacin, meropenem and ciprofloxacin. The rmpA gene was determined in the K. pneumoniae isolates in 6 children. The “string-test” of these colonies of K. pneumoniae in all cases gave a positive result. The genes of siderophores, aerobactin and colibactin were found in 3 isolates. Aerobactin and colibactin produced only rmpA-bearing strains. 3 isolates (23%) of K. pneumoniae produced ESBL in Group 2. In 8 out of 13 cases there was rmpA–gene and genes of aerobactin and colibactin in 11 and 7 cases accordingly. The “string-test” was positive in 8 cases, and there were only rmpA-positive bacteria. Siderophores were detected both in rmpA-positive and rmpA-negative isolates. The microbes produced BLBR and were rmpA-positive in 2 children. In one case, the isolates had neither the characteristic virulence factors, nor BLBR.Conclusion. The risk of developing localized and generalized forms of neonatal klebsiella infection is largely determined by microbiological features of the microorganism, its resistance and virulence. We observed clinical variants of the disease caused by K. pneumoniae, which simultaneously had two properties: high aggressiveness and resistance to antibiotic therapy