High-field electron transport in doped ZnO

Current-voltage characteristics have been measured for ZnO:Ga and Zn:Sb epitaxial layers with electron densities ranging from 1.4x10(17) cm(-3) to 1.1 x 10(20) cm(-3). Two-terminal samples with coplanar electrodes demonstrate virtually ohmic behavior until thermal effects come into play. Soft damage of the samples takes place at high currents. The threshold power (per electron) for the damage is nearly inversely proportional to the electron density over a wide range of electron densities. Pulsed voltage is applied in order to minimize the thermal effects, and thus an average electric field of 150 kV cm(-1) is reached in some samples subjected to 2 ns voltage pulses. The results are treated in terms of electron drift velocity estimated from the data on current and electron density under the assumption of uniform electric field. The highest velocity of similar to 1.5 x 10(7) cm s(-1) is found at an electric field of similar to 100 kV cm(-1) for the sample with an electron density of 1.4 x 10(17) cm(-3). The nonohmic behavior due to hot-electron effects is weak, and the dependence of the electron drift velocity on the doping resembles the variation of mobility

Evaluation of External and Internal Threats to Sanitary-Epidemiological Welfare of the Population in the Context of Mass Sporting Events

Mass gatherings (MGs) always incur some kind of potential hazard associated with incipiency of emergency situations with sanitary-epidemiological bias (ES). Upcoming Universiade (World Student Games) in Kazan (July, 2013) raises an issue of implementation of a unified system of approaches to the effective provision of sanitary-epidemiological welfare of the population, taking due account of peculiarities and specific conditions under which the MG will be conducted. Therewith key objective of this study has been formulated as elaboration of the system based on epidemiological assessment of real and potential threats at the MG. Analyzed have been the data on 37 MGs carried out over the period of 25 years since 1987 up to 2012; investigated is epidemiological situation in 170 participating states. Worked out is a scheme of qualitative determination of potential epidemiological threat on the basis of comprehensive assessment of epidemiological risks in the endemic territories of the troubled regions. Distinguished is a complex of measures for the provision of sanitary-epidemiological welfare when managing the Universiade in Kazan heedful of high potential epidemiological hazard of this event

Assessment of the Potential Epidemic Hazard as Regards International Public Events in Terms of the Currently Important Infectious Diseases

International public events (IPE) present some actual epidemiological problems requiring proper methodological elaboration. In this respect for the first time developed has been the scheme of assessment of their potential epidemic hazard (PEH), based on integrated evaluation of epidemiological risk as regards infectious diseases listed in the IHR (2005). On the cholera model demonstrated is the fact that high priority hazard of public events emerges when those are combined with such elements of epidemiological risk as territory and time of a threat, as well as risk factors and risk contingents. Thus the integral effect of all elements realization is manifested through high probability of infectious disease importation, which is associated with emergency situation, into the public event location and the disturbance of mass gathering progress. Reliability and functionality of the developed scheme is verified on other infections too. PEH assessment procedure allows for timely identification of priority goals, for rating means and capacities, organizational resources, methodological and technological arrays for the provision of sanitary-epidemiological welfare and biological safety when managing public event

Epizootic Activity of Natural Plague Foci in the Territory of the Russian Federation in 2011, and Prognosis for 2012

Carried out is the assessment of epizootic activity of natural plague foci in the Russian Federation and in the Republic of Kazakhstan during the period of 2000-2010. It is specified that 38 plague microbe strains have been isolated in the territory of the Russian Federation, the total area of epizooties being 882,5 km2. Plague microbe strains are isolated in the territory of East-Caucasian high-mountain and Altai mountain natural foci. Identified are the reasons of low epizootic activity of plain and low-mountain natural plague foci in the Russian Federation. Outlined is the role of climatic factors in the development of current intense depression in numbers of carriers and vectors of plague. Put forward is the prognosis on the low epizootic activity of the natural plague foci in the Russian Federation in 2012. It is substantiated that the emergence of local epizooties in 2012 is to take place in the territory of Altai mountain, Tuvin mountain and East-Caucasian high-mountain natural plague foci

WEST NILE FEVER WORLDWIDE AND IN THE TERRITORY OF THE RUSSIAN FEDERATION IN 2016, AND FORECAST OF EPIDEMIC SITUATION DEVELOPMENT IN 2017

In Europe, as in Russia and Canada, outlined was a tendency to the increase in the morbidity rates, while in the US – the incidence was somewhat lower as compared to previous years. On the whole, West Nile fever incidence rates in the Russian Federation by regions during the epidemic season, 2016 were below the average long-term index. Above the average regional annual incidence rates were registered in the Saratov region only and accounted for 64 % of all reported cases in Russia. Analysis of the monitoring results indicated the circulation of WNF virus markers in carriers of the pathogen in 10 constituent entities of the Russian Federation, and the presence of IgG antibodies in healthy population cohorts in 30 RF entities. According to molecular-genetic typing of WNF virus samples from a deceased patient in the Astrakhan Region and mosquito Culex samples from the Volgograd Region, WNF virus genotype I was established. Forecasting of epidemiological situation development for the year 2017 does not rule out the possibility of local increase in WNF incidence in certain regions of Russia

Results of Monitoring over the West Nile Fever Pathogen in the Territory of the Russian Federation in 2017. Forecast of Epidemic Situation Development in Russia in 2018

In Europe, in the epidemic season 2017, the incidence of West Nile fever did not exceed the index of the previous season. In the US and Canada, there was an increase in the incidence of cases. West Nile fever morbidity rates in the Russian Federation and in separate constituent entities were below the average long-term index and had the lowest value for the period since 2008. 41.6 % of WNF cases were imported to Russia from the distant countries. Analysis of the monitoring results indicated the circulation of WNF virus markers in carriers of the pathogen in 6 constituent entities of the Russian Federation, and the presence of IgG antibodies in healthy population cohorts in 24 RF entities. According to molecular-genetic typing of WNF virus samples from mosquito Culex modestus from the Volgograd Region, WNF virus genotype II was established. Forecasting of epidemiological situation development for the year 2018 does not rule out the possibility of local increase in WNF incidence in certain regions of Russia

Improvement of the Scientifically-Substantiated Model of Sanitary-Epidemiological Welfare Provision During Mass Events by the Example of FIFA World Cup-2018 in Russia

In 2018, between June14 and July 15, final matches of the FIFA World Cup-2018 were held in 11 cities of the Russian Federation. That event was the biggest mass event with international participation in the history of Russia. During the period, in the process of sanitary-epidemiological welfare provision, developed earlier scintific-and-practical achievementds for prevention of emergency situations of sanitary-epidemiologoical character were implemented to the fullest extent. Objective of the study – analysis of evolution of the developed in Russia scientifically-substantiated approaches in the sphere of sanitary-epidemiological welfare provision of mass events and aggregation of the results of their implementation during preparation and holding of FIFA World-Cup-2018. Utilized were information-analytical materials from the Rospotrebnadzor Administrations by the constituent entities of the Russian Federatuion, Centers of Hygiene and Epidemiology in the entities of the Russian Federation, RusRAPI “Microbe” of the Rospotrebnadzor, data from Organizing Committee “Russia-2018”, Federal Turism Agency, information published in periodical press. Scientifically substantiated model of sanitary-epidemiological welfare provision during mass events was developed in the Russian Federation. It includes expert evaluation and quantification of potential epidemic hazard of mass event which allows for targeted prophylactic and anti-epidemic measures with rationalized loads and adequate frequency of repeat. The paper discusses the complex of measures carried out during preparation and holding of FIFA World Cup-2018 by the functional areas: sanitary protection of the territory; epidemiological surveillnace over relevant  anthropozoonotic, natural-focal zoonotic, sapronotic infectious diseaseas; sanitary surveillance over communal facilities, catering facilities, sites of accomodation of the participants and guests; sanitary-hygienic monitoring of ambient environment objects; provision of anti-epidemic preparadeness and readiness of the Rospotrebnadzor authorities and institutions and medical organizations; provision of readiness of laboratory facilities; involvement of additional forces and capacities and interagency cooperation in response to emergency situations of sanitary-epidemiological character