104 research outputs found

    Age criteria for American bison

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    Preliminary Report on a Stratified Late Archaic-Woodland Era Rockshelter in Rogers County, Oklahoma

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    In northeastern Oklahoma, very little is known about the transition from the Late Archaic to the Woodland period (Wyckoff and Brooks, 1983: 55). To date, most of the archeological evidence documenting this time period has been derived from sites with mixed or otherwise uncertain components. In this report, we present a preliminary description of a small rockshelter, 34RO252, which has a Late Archaic deposit stratigraphically below a Woodland era cultural deposit. These two deposits are unmixed, discrete, and are physically separated by an apparently sterile clay soil horizon. It is anticipated that the stratified cultural deposits at this site will help characterize the transition from the Late Archaic to the Early Woodland period along the Verdigris River in northeast Oklahoma. This site was first reported in April 1994 by two men who had discovered partially exposed human skeletal remains located in the rear remnant of a rockshelter at Oologah Lake in Rogers County, Oklahoma. The two men illegally excavated the remains and removed them from the site. 1 The rockshelter where the remains originated was subsequently examined by the authors and additional skeletal material was identified, in situ, in an exposed soil profile. A series of three radiocarbon assays, described below, placed the cultural deposit and the human remains within the Late Archaic-Woodland period (circa 780 B.C. to A.O. 900).2 This site is provisionally classified as corresponding to a cultural sequence that includes the old Grove C described by Purrington and Vehik

    Reproductive Correlates of a Perineal Gland in the Hispid Cotton Rat

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    During studies of the annual cycle of reproduction in the hispid cotton rat (Sigmodon hispidus) in southeastern Virginia, we discovered an anal (more specifically, perineal) gland that is present only in males during the breeding season. The perineal gland encircles the lower end of the rectum and has ductal connections to the urethra, through which its secretions likely are delivered. This fatty gland is highly developed in breeding males but, like the testes and seminal vesicles, regresses during the winter non-breeding season. The prominence and cyclicity of the perineal gland suggests that it somehow facilitates normal reproduction. The combined mass of testes, seminal vesicles, and perineal gland constitutes only about 0.01 percent of the body mass of large males during the non-breeding season, but as much as 4.8 percent of body mass during the breeding season. Thus, males devote a large amount of energy to growing and maintaining these glands in anticipation of and during the breeding season. Despite two field trials, the function of the perineal gland and the nature of its secretion are unknown

    SARS-CoV-2 Receptor ACE2 Is an Interferon-Stimulated Gene in Human Airway Epithelial Cells and Is Detected in Specific Cell Subsets across Tissues.

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    There is pressing urgency to understand the pathogenesis of the severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2), which causes the disease COVID-19. SARS-CoV-2 spike (S) protein binds angiotensin-converting enzyme 2 (ACE2), and in concert with host proteases, principally transmembrane serine protease 2 (TMPRSS2), promotes cellular entry. The cell subsets targeted by SARS-CoV-2 in host tissues and the factors that regulate ACE2 expression remain unknown. Here, we leverage human, non-human primate, and mouse single-cell RNA-sequencing (scRNA-seq) datasets across health and disease to uncover putative targets of SARS-CoV-2 among tissue-resident cell subsets. We identify ACE2 and TMPRSS2 co-expressing cells within lung type II pneumocytes, ileal absorptive enterocytes, and nasal goblet secretory cells. Strikingly, we discovered that ACE2 is a human interferon-stimulated gene (ISG) in vitro using airway epithelial cells and extend our findings to in vivo viral infections. Our data suggest that SARS-CoV-2 could exploit species-specific interferon-driven upregulation of ACE2, a tissue-protective mediator during lung injury, to enhance infection

    CERN openlab Summer Student Lightning Talks

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    X-ray study and synthesis of some copper-lead oxychlorides /

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    Farmer response to lift.

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    The LIFT Program was introduced by the Canadian Wheat Board and the Federal Cabinet in March of 1970. The program was designed to reduce the number of acres seeded to wheat in the spring of 1970 and thereby reduce the size of wheat stocks in Canada. The objectives of this study of the LIFT Program were; 1. to determine which factors were important in predicting the extent of participation by individual farmers in the LIFT Program; 2. to determine how effective the LIFT Program was in reducing wheat acreage. Data for the study was collected by means of interviewing a random sample of farm operators in the grain growing areas of Alberta and Saskatchewan. Multiple linear regression was used to determine the factors which were most important in predicting the extent of participation in the LIFT Program. The importance of qualitative variables was analysed by chi-square and analysis of variance techniques. The following eight variables were found to be important in predicting the extent of participation in the LIFT Program. 1. number of bushels of wheat on hand per cultivated acre 2. age of operator 3. knowledge of the LIFT Program 4, acres of wheat in 1969 5. grade completed in school by operator's wife 6. "attitude towards change" score 7. attitude towards the LIFT Program, and 8. percentage of summer fallow in the normal crop rotation. These eight variables explained 61.94% of the variation in the extent of participation in the LIFT Program. It was concluded that knowledge of the LIFT Program, attitude towards the LIFT Program, dissemination of information about the program by group methods and by government sources all had an important influence on the extent of participation. It was further concluded that the LIFT Program either directly or indirectly influenced about two thirds of the wheat acreage reduction that occurred in 1970.Land and Food Systems, Faculty ofGraduat

    Dietary Overlap of an Alien and Native Carnivore on San Clemente Island, California

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    Predation by feral cats (Felis catus) is recognized as a major threat to native fauna worldwide, but the competitive effects of cats on native species have not been extensively studied. Cats occur on San Clemente Island, California, in sympatry with endemic island foxes (Urocyon littoralis clementae). We examined diets of cats and island foxes between years, seasons, and habitats to assess the potential for resource competition between the 2 species. Analysis of 602 cat and 958 fox feces revealed a high level of dietary overlap (O = 0.93) and relatively narrow niche breadths for both species (Bstandard Fox = 0.37; Bstandard Cat = 0.49). Despite the overlap in diet, cats and foxes appear to partition prey resources. Cats consume approximately equal proportions of arthropod (47.9%) and vertebrate (44.2%) prey, the latter primarily rodents (29.2%) and lizards (12.9%). In contrast, foxes appear to rely more on arthropods (57.7%), with plants (20.5%) and vertebrates (21.6%) occurring in lower, but roughly equal frequencies. Season appeared to have little effect on diet; however, diet did vary between habitats and years for both species. Diets of cats on San Clemente Island are consistent with those from other studies. We found no evidence of a dietary shift by foxes that were in sympatry with cats
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