5,336 research outputs found
USSR Space Life Sciences Digest, issue 32
This is the thirty-second issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 34 journal or conference papers published in Russian and of 4 Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 18 areas of space biology and medicine. These areas include: adaptation, aviation medicine, biological rhythms, biospherics, cardiovascular and respiratory systems, developmental biology, exobiology, habitability and environmental effects, human performance, hematology, mathematical models, metabolism, microbiology, musculoskeletal system, neurophysiology, operational medicine, and reproductive system
The telomerase essential N-terminal domain promotes DNA synthesis by stabilizing short RNA-DNA hybrids.
Telomerase is an enzyme that adds repetitive DNA sequences to the ends of chromosomes and consists of two main subunits: the telomerase reverse transcriptase (TERT) protein and an associated telomerase RNA (TER). The telomerase essential N-terminal (TEN) domain is a conserved region of TERT proposed to mediate DNA substrate interactions. Here, we have employed single molecule telomerase binding assays to investigate the function of the TEN domain. Our results reveal telomeric DNA substrates bound to telomerase exhibit a dynamic equilibrium between two states: a docked conformation and an alternative conformation. The relative stabilities of the docked and alternative states correlate with the number of basepairs that can be formed between the DNA substrate and the RNA template, with more basepairing favoring the docked state. The docked state is further buttressed by the TEN domain and mutations within the TEN domain substantially alter the DNA substrate structural equilibrium. We propose a model in which the TEN domain stabilizes short RNA-DNA duplexes in the active site of the enzyme, promoting the docked state to augment telomerase processivity
USSR Space Life Sciences Digest, issue 30
This is the thirtieth issue of NASA's Space Life Sciences Digest. It contains abstracts of 47 journal papers or book chapters published in Russian and of three Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 20 areas of space biology and medicine. These areas include: adaptation, biospheric research, cardiovascular and respiratory systems, endocrinology, equipment and instrumentation, gastrointestinal system, group dynamics, habitability and environmental effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, musculoskeletal system, neurophysiology, nutrition, psychology, radiobiology, and space biology and medicine
USSR Space Life Sciences Digest, issue 29
This is the twenty-ninth issue of NASA's Space Life Sciences Digest. It is a double issue covering two issues of the Soviet Space Biology and Aerospace Medicine Journal. Issue 29 contains abstracts of 60 journal papers or book chapters published in Russian and of three Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. A review of a book on environmental hygiene and a list of papers presented at a Soviet conference on space biology and medicine are also included. The materials in this issue were identified as relevant to 28 areas of space biology and medicine. The areas are: adaptation, aviation medicine, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, developmental biology, digestive system, endocrinology, equipment and instrumentation, genetics, habitability and environment effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, musculoskeletal system, neurophysiology, nutrition, personnel selection, psychology, radiobiology, reproductive system, space biology and medicine, and the economics of space flight
Digest of Russian Space Life Sciences, issue 33
This is the thirty-third issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 55 papers published in Russian journals. The abstracts in this issue have been identified as relevant to the following areas of space biology and medicine: biological rhythms, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, equipment and instrumentation, gastrointestinal system, genetics, hematology, human performance, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, psychology, radiobiology, and reproductive system
The Sedimentology and Stratigraphy of the Sentinel Butte Formation Around Beicegel Creek, McKenzie County, North Dakota
Approximately 580 ft of the Sentinel Butte Formation (Paleocene) is exposed within this study area. A stratigraphic and sedimentologic study of these exposures was done in order to gather new information about the formation, to interpret paleodepositional environments, and to possibly develop an overall depositional model.
Stratigraphic analysis identified four major sand units within the study area, separated by intervals of mudstone and lignite. The lowermost sandstone unit is identified as the Basal Sandstone (Royse 1967). All of the sandstone units exhibit sedimentary structures that suggest a fluvial source for their deposition. They tend to be laterally consistent and when mapped show a meandering trend. This along with the existence of floodplain and back swamp deposits in close proximity to these sands leads to the hypothesis that this interval of Sentinel Butte sediments were deposited by a meandering fluvial system.
Sedimentologic analysis of the Basal Sandstone determined that it should be classified as a medium-grain (Wentworth) litharenite (Folk, 1980). The analysis of the upper sand showed that this unit should be classified as a fine-grained (Wentworth) litharenite to sublitharenite. The basal sand textural analysis produced mean grain size of 2.18tj\u3e, while the upper sand showed a mean grain size of 3.0
The Prevalence of Dual Diagnosis of Generalized Anxiety Disorder and Alcoholism in the Literature: A Critical Meta-Analytic Review
The relationship between alcoholism and generalized anxiety disorder (GAD) has been discussed in two research areas: research on the prevalence of GAD in alcoholics, and the prevalence of alcoholism in individuals diagnosed with GAD. Studies indicate that between 6 to 26% of alcoholics have a current diagnosis of GAD, with a lifetime prevalence rate of up 51%. In the general population, 4% would currently receive a diagnosis of GAD, with a lifetime prevalence of 8%.
This meta-analytic review of the empirical literature examines the relationship between GAD and alcoholism. The author used percentages to compare the results of various studies. The averaged results of these various studies suggested there is a 25% comorbidity rate of GAD and alcoholism. critical review of the studies examined in this review revealed substantial methodological errors. Based on a critical review of the research methodology in the studies cited, the author proposed further research
Induced resistance to bacitracin and penicillin in cultures of staphylococcus aureus
Thesis (Ph.D.)--Boston University, 1948. This item was digitized by the Internet Archive
Dark matter, neutron stars and strange quark matter
We show that self-annihilating neutralino WIMP dark matter accreted onto
neutron stars may provide a mechanism to seed compact objects with long-lived
lumps of strange quark matter, or strangelets, for WIMP masses above a few GeV.
This effect may trigger a conversion of most of the star into a strange star.
We use an energy estimate for the long-lived strangelet based on the Fermi gas
model combined with the MIT bag model to set a new limit on the possible values
of the WIMP mass that can be especially relevant for subdominant species of
massive neutralinos.Comment: 5 pages, 2 figures, accepted for publication in Phys. Rev. Let
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