1,112 research outputs found
Risk Factors for the Development of Uveitis
Uveitis is one of the main causes of eye disease and blindness. Worldwide, uveitis is associated with 5 to 10% of visual impairments, with 35% of patients diagnosed with the disease having significant vision loss and some reaching complete blindness. Uveitis is a common, eye-threatening inflammatory eye disease and involves a number of heterogeneous clinical formations. The prevalence of different types of uveitis depends on many factors, such as age, sex, race, geographical distribution, environmental influences, genetics and social habits. The aim is to present the risk factors for the development of uveitis based on the literature review. Material and methods: An extensive study of scientific articles was conducted in the PubMed, ScienceDirect and Scopus databases, using the following keywords: uveitis, epidemiology, frequency, risk factors, prevalence. Based on the obtained results, a synthesized review of the risk factors and the prevalence of uveitis was made. Most studies related to uveitis have been conducted in developed countries. In these studies, the incidence was between 17 and 52 per 100,000 people per year, and the prevalence was 38-714 cases per 100,000 population. Up to 25% of cases of blindness in developing countries are associated with uveitis. When diagnosing the type of uveitis, it is necessary to take into account the location, onset of the disease, duration and clinical course. Conclusion: Knowledge of regional patterns and risk factors for the disease is essential. The more detailed classification of uveitis with the establishment of uniform diagnostic criteria and prospective population-based studies have a significant impact on epidemiological studies and clinical practice
Specific interplanetary conditions for CIR-, Sheath-, and ICME-induced geomagnetic storms obtained by double superposed epoch analysis
The comparison of specific interplanetary conditions for 798 magnetic storms
with Dst < -50 nT for the period 1976-2000 was made on the basis of the OMNI
archive data.We categorized various large-scale types of solar wind as
interplanetary drivers of storms: corotating interaction region (CIR), Sheath,
interplanetary CME (ICME) including magnetic cloud (MC) and Ejecta, separately
MC and Ejecta, and "Indeterminate" type. The data processing was carried out by
the method of double superposed epoch analysis which uses two reference times
(onset of storm and the minimum Dst index) and make a re-scaling of main phase
of storm a such way that after this transformation all storms have equal
durations of main phase in new time reference frame. This method reproduced
some well-known results and allowed us to obtain some new results.
Specifically, obtained results demonstrate high importance of Sheath in
generation of magnetic storms as well as a significant differences in
properties of MC and Ejecta and in their geoeffectiveness.Comment: 21 pages, 9 figures, 1 table, submitted to J. of Advances in Space
Research on 29 July, 2009 for Special Issue "Space Weather Advances
The role of information technology training in the conditions of informatization education
This article presents the role of informatization of education in the university. The positive aspects of the use of information technology in the educational process of both students and teachers are also consideredВ настоящей статье представлена роль информатизации образования в ВУЗе. Также рассмотрены положительные моменты использования информационных технологий в учебном процессе как студентов, так и преподавателе
СЛЕДЫ СЕЙСМИЧЕСКОЙ АКТИВНОСТИ В ДОННЫХ ОСАДКАХ ОЗЕР ВОСТОЧНОЙ ФЕННОСКАНДИИ
This paper presents the results of a study on traces of ancient earthquakes in the lake bottom sediments of eastern Fennoscandia (Kola region and Karelia). Based on the sediment cores from six lake basins located within large active structures of the region, consideration is being given to the most typical features of sedimentation affected by neotectonic movements of the Earth’s crust. The data presented here provide lithological-stratigraphical, paleobotanical and chronometrical evidence for lakes. The paper causes and mechanisms of formation of seismic structures in bottom sediments and their distinction from deformations of another origin.Generalized earthquake history in provided an opportunity to organize the existing information on the time of paleoearthquake manifestations and distinguish three active periods in paleoseismicity. These are Late Glaciation-Early Holocene marked by the most rapid uplift after the retreat of the last ice sheet (13500–8100 cal yr BP), Middle Holocene (6800–6600 cal yr BP), and Late Holocene (3100–200 cal yr BP). The results of this study showed that the number and intensity of seismic events changed at different stages of sedimentation. Since the Younger Dryas, fault zones (or their segments) have been repeatedly activated. Combined with the data on paleoseismicity in adjacent parts of Fennoscandia, our studies indicate an irregular pattern of the Late Pleistocene-Holocene seismic activity in stable areas formerly covered by glaciers. The obtained data make further adjustments to the neogeodynamic and seismic estimates of intraplate areas.В работе представлен обзор полученных в последние годы новых данных о следах древних землетрясений в донных осадках озер Восточной Фенноскандии (Кольский регион и Карелия). На примерах изучения осадочных кернов из шести озерных котловин, расположенных в зонах крупных активных структур региона, рассматриваются наиболее характерные особенности седиментации осадков в условиях новейших тектонических перемещений земной коры. Приводятся литолого-стратиграфические, палеоботанические, хронометрические данные по озерам. Обсуждаются различные причины и механизмы образования сейсмически индуцированных структур в донных осадках и признаки отличия их от деформаций, образованных иными процессами.Обобщенные сведения о сейсмическом прошлом Карело-Кольского региона упорядочили ранее существующую информацию о времени проявления палеоземлетрясений: удалось выделить три активных возрастных рубежа. Это периоды позднеледниковья – начала голоцена, ознаменовавшиеся наиболее быстрым поднятием территории после исчезновения последнего ледникового покрова (13500–8100 кал.л.н.), среднего (6800–6600 кал.л.н) и позднего (3100–200 кал.л.н.) голоцена. Результаты исследований показали, что количество и интенсивность сейсмических событий менялись на разных этапах накопления осадочной толщи. Начиная с позднего дриаса фиксируется неоднократная активизация разломных зон (или их сегментов). В сочетании с данными о палеосейсмичности в смежных районах Фенноскандии наши исследования указывают на неравномерное проявление позднеплейстоцен-голоценовой сейсмической активности стабильных территорий, прежде покрывавшихся оледенениями. Полученные данные вносят дополнительные коррективы в оценку новейшей геодинамики и сейсмичности внутриплатформенных территорий
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