Annama H chondrite-Mineralogy, physical properties, cosmic ray exposure, and parent body history

The fall of the Annama meteorite occurred early morning (local time) on April 19, 2014 on the Kola Peninsula (Russia). Based on mineralogy and physical properties, Annama is a typical H chondrite. It has a high Ar-Ar age of 4.4 Ga. Its cosmic ray exposure history is atypical as it is not part of the large group of H chondrites with a prominent 7-8 Ma peak in the exposure age histograms. Instead, its exposure age is within uncertainty of a smaller peak at 30 +/- 4 Ma. The results from short-lived radionuclides are compatible with an atmospheric pre-entry radius of 30-40 cm. However, based on noble gas and cosmogenic radionuclide data, Annama must have been part of a larger body (radius >65 cm) for a large part of its cosmic ray exposure history. The Be-10 concentration indicates a recent (3-5 Ma) breakup which may be responsible for the Annama parent body size reduction to 30-35 cm pre-entry radius.Peer reviewe

The Sariçiçek Howardite Fall in Turkey: Source Crater of HED Meteorites on Vesta and İmpact Risk of Vestoids

The Sariçiçek howardite meteorite shower consisting of 343 documented stones occurred on 2 September 2015 in Turkey and is the first documented howardite fall. Cosmogenic isotopes show that Sariçiçek experienced a complex cosmic ray exposure history, exposed during ~12–14 Ma in a regolith near the surface of a parent asteroid, and that an ~1 m sized meteoroid was launched by an impact 22 ± 2 Ma ago to Earth (as did one third of all HED meteorites). SIMS dating of zircon and baddeleyite yielded 4550.4 ± 2.5 Ma and 4553 ± 8.8 Ma crystallization ages for the basaltic magma clasts. The apatite U-Pb age of 4525 ± 17 Ma, K-Ar age of ~3.9 Ga, and the U,Th-He ages of 1.8 ± 0.7 and 2.6 ± 0.3 Ga are interpreted to represent thermal metamorphic and impact-related resetting ages, respectively. Petrographic, geochemical and O-, Cr- and Tiisotopic studies confirm that Sariçiçek belongs to the normal clan of HED meteorites. Petrographic observations and analysis of organic material indicate a small portion of carbonaceous chondrite material in the Sariçiçek regolith and organic contamination of the meteorite after a few days on soil. Video observations of the fall show an atmospheric entry at 17.3 ± 0.8 kms-1 from NW, fragmentations at 37, 33, 31 and 27 km altitude, and provide a pre-atmospheric orbit that is the first dynamical link between the normal HED meteorite clan and the inner Main Belt. Spectral data indicate the similarity of Sariçiçek with the Vesta asteroid family (V-class) spectra, a group of asteroids stretching to delivery resonances, which includes (4) Vesta. Dynamical modeling of meteoroid delivery to Earth shows that the complete disruption of a ~1 km sized Vesta family asteroid or a ~10 km sized impact crater on Vesta is required to provide sufficient meteoroids ≤4 m in size to account for the influx of meteorites from this HED clan. The 16.7 km diameter Antonia impact crater on Vesta was formed on terrain of the same age as given by the 4He retention age of Sariçiçek. Lunar scaling for crater production to crater counts of its ejecta blanket show it was formed ~22 Ma ago

Devising an Engineering Procedure for Calculating the Ductility of a Roller Bearing Under a No-central Radial Load

Known theoretical approaches to calculating the ductility of rolling bearings include rather complicated analytical dependences and require cumbersome computation. That makes it a relevant task to undertake a research aimed at the development of an engineering approach to the calculation of radial ductility of bearings.The current study proposes an engineering method for determining radial ductility using cylindrical roller bearings as an example. It accounts for the radial gap, contact deformation of parts, the deformations of bending and misalignment of rings for cases when a bearing is exposed to the action of a central radial load and a radial load with eccentricity. The adopted simplified linear calculation model for determining the angle of rings misalignment is valid for small angles when contact is maintained over the entire length of the roller. Computation of radial ductility of roller bearings under a no-central radial load is based on determining the sum of variable elastic deformations in a contact between rings and the most loaded roller. The values for elastic deformations are determined from known formulae for solving the contact problem in elasticity theory taking into consideration a mismatch between the geometric centers of outer and inner rings.Adequacy of the proposed engineering procedure has been confirmed by results from calculating the specific ductility of the cylindrical roller bearing 2211 with a central radial load. By using the proposed methodology, we have derived values for specific ductility that are 3...4 % lower compared to similar results obtained from a known procedure. By using the cylindrical roller bearing 42726 as an example, we have investigated structural parameters considering a no-central radial load. A decrease in the bearing 42726 ductility with an increase in the number of rollers and rigidity of the outer ring has been shown, as well as with a decrease in the eccentricity of a radial load.The ductility of rolling bearings must be known when constructing dynamic models of certain machines: machine tool spindles, shaft-gears at large-size reducers, crane structures. Therefore, the proposed engineering procedure for determining the ductility of roller bearings at small angles of rings misalignment could be applied in the practice of designing machines and mechanisms for which the elastic characteristics of all their components are important

Научные журналы по библиотековедению, библиографоведению и книговедению: история, реалии, перспективы

The article presents the presentations of the participants of the round table “Scientific Journals on Library Science, Bibliography Science and Book Studies: History, Realities, Prospects (to the 70th anniversary of the journal “Bibliotekovedenie” (Library Science)”, which took place on April 19, 2022 within the framework of the International Scientific and Practical Conference “Rumyantsev Readings — 2022”. The paper reflects the place and role of the professional scientific journals in the development of communications that contribute to the preservation of libraries as cultural heritage institutions and form the human capital and cultural potential of all generations of Russian citizens.The journal “Library Science”, established in 1952, became the nationwide scientific periodical of the library sector. Participants described in their speeches the characteristics of the publication activity of some Russian journals, professional periodicals of Belarus, Kazakhstan, Azerbaijan and the international scientific journal “Libri”. The authors highlighted the peculiarities of the creation of periodicals of the designated subject, their functioning, the management models used, the diversity of elements of publication policy and design: regional differences, typological characteristics of the founders, departmental affiliation, cultural traditions, the uniqueness of the historical conditions of creation, etc.The discussion resulted in unanimous recognition of the significant role of professional scientific periodicals in supporting the scientific infrastructure of libraries and providing methodological support of the sector, including research practices, as well as atmosphere of creativity and creative competencies. In the future, the journals are considered as points of growth of professional knowledge, interdisciplinary thinking and cultural communications, activators of the socio-cultural space.Представлены выступления участников круглого стола «Научные журналы по библиотековедению, библиографоведению и книговедению: история, реалии, перспективы (к 70-летию журнала “Библиотековедение”)», который состоялся 19 апреля 2022 г. в рамках Международной научно-практической конференции «Румянцевские чтения — 2022». Отражены место и роль профессиональных научных журналов в развитии коммуникаций, способствующих сохранению библиотек как учреждений культурного наследия и формирующих человеческий капитал и культурный потенциал всех поколений граждан России.Журнал «Библиотековедение», созданный в 1952 г., стал общенациональным научным периодическим изданием библиотечной отрасли, задачи которого в разные периоды фокусировались на проблемах становления библиотек как активных участников процессов, происходящих в обществе, и их отражении в научных исследованиях. «Библиотековедение» остается признанным и наиболее авторитетным журналом.В выступлениях участников были отмечены характеристики публикационной активности некоторых российских журналов, профессиональной периодики Беларуси, Казахстана, Азербайджана и международного научного журнала Libri.Выделены особенности создания периодических изданий обозначенной тематики, их функционирования, используемых управленческих моделей, разнообразие элементов публикационной политики и оформления: региональные различия, типологические характеристики учредителей, ведомственная принадлежность, культурные традиции, уникальность исторических условий создания и др.Итогом обсуждения стало единодушное признание значимой роли профессиональной научной периодики в поддержке научной инфраструктуры библиотек и методического обеспечения отрасли, включая исследовательские практики, атмосферу творчества и креативных компетенций. В перспективе журналы рассматриваются как точки роста профессиональных знаний, междисциплинарного мышления и культурных коммуникаций, активаторы социокультурного пространства

Second Black Sea Symposium For Young Scientists In Biomedicine March 27-30, 2014, Varna, Bulgaria

Варненски медицински форум (Varna Medical Forum) V. 3, Suppl 1(2014

Treatment patterns and use of resources in patients with tuberous sclerosis complex : insights from the TOSCA registry

Tuberous Sclerosis Complex (TSC) is a rare autosomal-dominant disorder caused by mutations in the TSC1 or TSC2 genes. Patients with TSC may suffer from a wide range of clinical manifestations; however, the burden of TSC and its impact on healthcare resources needed for its management remain unknown. Besides, the use of resources might vary across countries depending on the country-specific clinical practice. The aim of this paper is to describe the use of TSC-related resources and treatment patterns within the TOSCA registry. A total of 2,214 patients with TSC from 31 countries were enrolled and had a follow-up of up to 5 years. A search was conducted to identify the variables containing both medical and non-medical resource use information within TOSCA. This search was performed both at the level of the core project as well as at the level of the research projects on epilepsy, subependymal giant cell astrocytoma (SEGA), lymphangioleiomyomatosis (LAM), and renal angiomyolipoma (rAML) taking into account the timepoints of the study, age groups, and countries. Data from the quality of life (QoL) research project were analyzed by type of visit and age at enrollment. Treatments varied greatly depending on the clinical manifestation, timepoint in the study, and age groups. GAB Aergics were the most prescribed drugs for epilepsy, and mTOR inhibitors are dramatically replacing surgery in patients with SEGA, despite current recommendations proposing both treatment options. mTOR inhibitors are also becoming common treatments in rAML and LAM patients. Forty-two out of the 143 patients (29.4%) who participated in the QoL research project reported inpatient stays over the last year. Data from non-medical resource use showed the critical impact of TSC on job status and capacity. Disability allowances were more common in children than adults (51.1% vs 38.2%). Psychological counseling, social services and social worker services were needed by <15% of the patients, regardless of age. The long-term nature, together with the variability in its clinical manifestations, makes TSC a complex and resource-demanding disease. The present study shows a comprehensive picture of the resource use implications of TSC