8 research outputs found
Диагностика остеопенического синдрома. Остеопенический синдром у больных бронхиальной астмой
Osteopenic syndrome in chronic obstructive pulmonary diseases including bronchial asthma represents actual and insufficiently studied area of medical science in view of ambiguous data on influence of glucocorticosteroid therapy and inflammation as basic pathogenetic mechanisms of bronchial asthma on bone metabolism. This review covers issues of pathogenesis and diagnosis of secondary osteopenic syndrome in patients with bronchial asthma.Остеопенический синдром при хронических обструктивных заболеваниях легких, в том числе и при бронхиальной астме, представляет собой актуальную и малоизученную область медицинской науки ввиду неоднозначных данных о воздействии глюкокортикостероидной терапии и воспаления как основного патогенетического механизма бронхиальной астмы на костный метаболизм. В настоящем обзоре освещены вопросы патогенеза и диагностики вторичного остеопенического синдрома у больных бронхиальной астмой
Reevaluation of Late Pleistocene loess profiles at Remizovka (Kazakhstan) indicates the significance of topography in evaluating terrestrial paleoclimate records
We report on a loess-paleosol sequence (LPS) near Remizovka, located in the northern Tian Shan piedmont of southeastern Kazakhstan. This site represents a key record for Late Pleistocene climatic fluctuations at the intersection of major northern hemisphere climate subsystems. This paper develops a synthesized dataset of previous conflicting studies at Remizovka by characterizing their (paleo)topographic context, which had remained previously overlooked. Digital elevation models, satellite images, and archival photography characterize recent topographic developments. Two well-developed pedocomplexes, which we investigate in detail and date by luminescence mark the paleotopography during Marine Oxygen Isotope Stage (MIS) 5. Peak dust accumulation rates here occurred during the middle MIS 5 and MIS 4/early MIS 3. These are partially comparable with records from neighboring regions, but not in phase with global ice volume records. This discrepancy may be related to a distinct regional environmental response to larger-scale climatic drivers and local topographic influences on dust deposition patterns. Our findings confirm the potential of the LPS Remizovka to provide high-resolution paleoclimate data for the Late Pleistocene. The three-dimensional stratigraphic reconstruction reinforces the caution required to correctly interpret loess formation processes prior to their interpretation as paleoclimate archives, and provides guidelines for a more suitable approach
A Novel Proxy for Tracking the Provenance of Dust Based on Paired E<sub>1'</sub>-Peroxy Paramagnetic Defect Centers in Fine-Grained Quartz
Crystal lattice defects in quartz have long been exploited for age determination, yet also show potential for sediment provenance studies. Here, we introduce a novel method for tracking aeolian dust provenance by utilizing the natural accumulation of E1’ and peroxy defect centers in quartz. Our approach is based on the previously observed premise that E1’ and peroxy centers arise from Frenkel defect pairs, and that their concentration increases with the age of the quartz-bearing source rock. We propose that these defect centers can be utilized as a characteristic feature of the source rock and consequently, for fingerprinting sediments derived from it. We successfully apply our new protocol to distinguish fine-grained quartz extracted from loess deposits from two regions in Central Asia which are known to derive from different source material of differing age. Our method offers strong potential for identifying variability in source, both spatially and through time down sedimentary sequences