Structure of herd immunity to SARS-COV-2 in the Krasnoyarsk region population in the COVID-19 epidemic

Purpose. Determination of the SARS-CoV-2 population humoral immunity among the population of the Krasnoyarsk Territory during the COVID-19 epidemic.Materials and methods. The study was carried out as a part of project for assessing population immunity to SARS-CoV-2 among the population of Russian Federation using unified methodology developed by Rospotrebnadzor, with the participation of the Research Institute for Epidemiology and Microbiology named by Pasteur, and taking into account the recommendations of the WHO. The work involved 2907 volunteers, selected by the online survey and randomization by age and territory. All volunteers were divided into 7 age groups: 1–17, 18–29, 30–39, 40–49, 50–59, 60–69, 70 and older (70+), including a total 246–449 people. Population immunity testing was carried out during the formation of groups (1st stage), and then twice more, with the interval of 6–8 weeks. Serum was obtained from venous blood samples obtained from volunteers, in which antibodies to the SARS-CoV-2 nucleocapsid were determined by the enzyme immunoassay. The results were analyzed by methods of nonparametric statistics: median, interquartile range, rank correlation coefficient were calculated in the Excel statistical package. The confidence interval to seroprevalence indicators (95% CI) was calculated using the WinPepi statistical package (version 11.65). The statistical significance of the differences was assessed with a probability level of p ≤ 0.05.Results. The seroprevalence of the population of the Krasnoyarsk Territory during the 5-month period of seromonitoring had increased 3.3 times from 12.8% (95% CI 11.3–14.4) to 41.7% (95% CI 39.4–4.0) , while the grouping by age had not revealed any peculiarities throughout the study. The trend towards a decrease in the incidence was formed on the 6th week of 2021. The seroprevalence of convalescents after COVID-19 during the initial testing was 61.5% (95% CI 40,6–79.8), among those who were in contact with patients with COVID-19 or convalescents –23.8% (95% CI 13.9–36.2) . Among the volunteers, 347 seropositive persons were identified, 324 of which were observed asymptomatic course.Conclusion. The structure of the population humoral immunity to SARS-CoV-2 of he population of the Krasnoyarsk Territory has been investigated. It was found that an increase in seroprevalence to 41.7% (95% CI 39.4–4.0) was accompanied by a decrease in morbidity

A land-to-ocean perspective on the magnitude, source and implication of DIC flux from major Arctic rivers to the Arctic Ocean

Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 26 (2012): GB4018, doi:10.1029/2011GB004192.A series of seasonally distributed measurements from the six largest Arctic rivers (the Ob', Yenisey, Lena, Kolyma, Yukon and Mackenzie) was used to examine the magnitude and significance of Arctic riverine DIC flux to larger scale C dynamics within the Arctic system. DIC concentration showed considerable, and synchronous, seasonal variation across these six large Arctic rivers, which have an estimated combined annual DIC flux of 30 Tg C yr−1. By examining the relationship between DIC flux and landscape variables known to regulate riverine DIC, we extrapolate to a DIC flux of 57 ± 9.9 Tg C yr−1for the full pan-arctic basin, and show that DIC export increases with runoff, the extent of carbonate rocks and glacial coverage, but decreases with permafrost extent. This pan-arctic riverine DIC estimate represents 13–15% of the total global DIC flux. The annual flux of selected ions (HCO3−, Na+, Ca2+, Mg2+, Sr2+, and Cl−) from the six largest Arctic rivers confirms that chemical weathering is dominated by inputs from carbonate rocks in the North American watersheds, but points to a more important role for silicate rocks in Siberian watersheds. In the coastal ocean, river water-induced decreases in aragonite saturation (i.e., an ocean acidification effect) appears to be much more pronounced in Siberia than in the North American Arctic, and stronger in the winter and spring than in the late summer. Accounting for seasonal variation in the flux of DIC and other major ions gives a much clearer understanding of the importance of riverine DIC within the broader pan-arctic C cycle.Funding for this work was provided through NSF-OPP-0229302 and NSF-OPP-0732985. Additional support to SET was provided by an NSERC Postdoctoral Fellowship.2013-06-1

The introduction of score-rating system of evaluating achievements of students on discipline "hospital therapy"

The article presents the score-rating system of evaluation of achievements of students in the department of hospital therapy.В статье представлена балльно-рейтинговая система оценки достижений студентов на кафедре госпитальной терапии

Quasiperiodic one-dimensional photonic crystals with adjustable multiple photonic band gaps

We propose an elegant approach to produce photonic band gap structures with multiple photonic band gaps (PBGs) by constructing quasiperiodic photonic crystals (QPPCs) composed by a superposition of photonic lattices with different periods. Generally QPPC structures exhibit both aperiodicity and multiple PBGs due to their long-range order. They are described by a simple analytical expression instead of quasiperiodic tiling approaches based on substitution rules. Here we describe the optical properties of quasiperiodic photonic crystals exhibiting two PBGs that can be tuned independently. PBG interband spacing and their depths can be varied by choosing appropriate reciprocal lattice vectors and their amplitudes. These effects are confirmed by the proof- of-concept measurements made for the porous silicon based QPPC of the appropriate design