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971.
This paper describes the behavior and activity patterns of a solitary adult male yellow baboon (Papio cynocephalus) living in the Amboseli National Park, Kenya. Social events surrounding the male's departure from his group, his contacts
with other baboons while solitary, and events surrounding his return to the group are described in detail. The distribution
of the male's time among several activity states, called histime budget, the average duration of these activities and the autocorrelation of activity states are analyzed and compared to the same
measures of activity taken on group living males. The information presented indicates that a solitary male, even when injured,
is not necessarily destined to die or to have a low reproductive potential. 相似文献
972.
Migration within the Roman Empire occurred at multiple scales and was engaged in both voluntarily and involuntarily. Because of the lengthy tradition of classical studies, bioarchaeological analyses must be fully contextualized within the bounds of history, material culture, and epigraphy. In order to assess migration to Rome within an updated contextual framework, strontium isotope analysis was performed on 105 individuals from two cemeteries associated with Imperial Rome—Casal Bertone and Castellaccio Europarco—and oxygen and carbon isotope analyses were performed on a subset of 55 individuals. Statistical analysis and comparisons with expected local ranges found several outliers who likely immigrated to Rome from elsewhere. Demographics of the immigrants show men and children migrated, and a comparison of carbon isotopes from teeth and bone samples suggests the immigrants may have significantly changed their diet. These data represent the first physical evidence of individual migrants to Imperial Rome. This case study demonstrates the importance of employing bioarchaeology to generate a deeper understanding of a complex ancient urban center. 相似文献
973.
Caitlin M. Worrell Ryan E. Wiegand Stephanie M. Davis Kennedy O. Odero Anna Blackstock Victoria M. Cuéllar Sammy M. Njenga Joel M. Montgomery Sharon L. Roy LeAnne M. Fox 《PloS one》2016,11(3)
Soil-transmitted helminth (STH) infections affect persons living in areas with poor water, sanitation, and hygiene (WASH). Preschool-aged children (PSAC) and school-aged children (SAC) are disproportionately affected by STH infections. We aimed to identify WASH factors associated with STH infection among PSAC and SAC in Kibera, Kenya. In 2012, households containing a PSAC or SAC were randomly selected from those enrolled in the International Emerging Infections Program, a population-based surveillance system. We administered a household questionnaire, conducted environmental assessments for WASH, and tested three stools from each child for STH eggs using the Kato-Katz method. WASH factors were evaluated for associations with STH infection using univariable and multivariable Poisson regression. Any-STH prevalence was 40.8% among 201 PSAC and 40.0% among 475 SAC enrolled. Using the Joint Monitoring Programme water and sanitation classifications, 1.5% of households reported piped water on premises versus 98.5% another improved water source; 1.3% reported improved sanitation facilities, while 81.7% used shared sanitation facilities, 13.9% had unimproved facilities, and 3.1% reported no facilities (open defecation). On univariable analysis, STH infection was significantly associated with a household toilet located off-premises (prevalence ratio (PR) = 1.33; p = 0.047), while always treating water (PR = 0.81; p = 0.04), covering drinking water containers (PR = 0.75; p = 0.02), using clean towels during hand drying (PR = 0.58; p<0.01), having finished household floor material (PR = 0.76; p<0.01), having electricity (PR = 0.70; p<0.01), and increasing household elevation in 10-meter increments (PR = 0.89; p<0.01) were protective against STH infection. On multivariable analysis, usually versus always treating water was associated with increased STH prevalence (adjusted prevalence ratio (aPR) = 1.52; p<0.01), while having finished household floor material (aPR = 0.76; p = 0.03), reported child deworming in the last year (aPR = 0.76; p<0.01), and 10-meter household elevation increases (aPR = 0.89; p<0.01) were protective against infection. The intersection between WASH and STH infection is complex; site-specific WASH interventions should be considered to sustain the gains made by deworming activities. 相似文献
974.
Dendritic cells (DCs) are potent antigen-presenting cells and therefore have enormous potential as vaccine targets. We have previously developed an engineered lentiviral vector (LV) that is pseudotyped with a mutated Sindbis virus glycoprotein (SVGmu), which is capable of targeting DCs through Dendritic Cell-specific ICAM3-grabbing Nonintegrin (DC-SIGN), a receptor that is predominantly expressed by DCs. In this study, we aimed to elucidate the internalization and trafficking mechanisms of this viral vector system through direct visualization of GFP-Vpr-tagged viral particles in target DCs, which was further corroborated by drug inhibition and dominant-negative mutants of cellular proteins that regulate the endocytic traffic. We demonstrated that our engineered LVs enter the cell via receptor-mediated clathrin- and dynamin-dependent endocytosis. Microtubule networks were also involved in a productive infection. Viral vector fusion was low-pH-dependent and occurred in the early endosomal stage of the intracellular transport. Autophagy was also examined for its effect on transduction efficiency, and we observed that enhanced autophage activity reduced vector infectivity, while suppressed autophagy boosted transduction efficiency. This study shed some light on the internalization and trafficking mechanisms of DC-directed LVs and offers some strategies to further improve the efficiency of LV-mediated gene therapy. 相似文献
975.
A comparison of Lateral Line Morphology of Blue Cod and Torrentfish: Two Sandperches of the Family Pinguipedidae 总被引:1,自引:0,他引:1
Parapercis colias (blue cod) and Cheimarrichthys fosteri (torrentfish) are two members of the family Pinguipedidae. They reside in habitats with different background levels of hydrodynamic
activity and differ in their feeding ecology. The peripheral morphology of the mechanosensory lateral line system was investigated
in each species. The torrentfish is the only freshwater member of this otherwise exclusively marine family. It resides in
turbulent fast flowing habitats and feeds nocturnally on stream drift. Torrentfish have many superficial neuromasts and a
simple unbranched canal system. In comparison the blue cod resides in sub-tidal slow flowing habitats, is a diurnal predator
and has relatively few superficial neuromasts and a well-developed branching canal system. For these two species the background
level of hydrodynamic activity does not appear to be the dominant selection pressure on lateral line morphology, in the case
of the torrentfish in particular it is more compelling to view lateral line morphology in the light of environmental pressures
that have favoured the evolution of nocturnal feeding. 相似文献
976.
977.
Kamal N. Tiwari John A. Montgomery John A. Secrist III 《Nucleosides, nucleotides & nucleic acids》2013,32(8):841-846
Abstract The procedure of Huang and Hui (Nucleosides & Nucleotide 1993, 12, 139-147) was found to give benzyl 3,5-di-O-benzyl-2-deoxy-1,4-dithio-α-L-threo-pentofuranoside (6) rather than the claimed D-erythro isomer. This sugar was converted to an anomeric mixture of the thymine nucleosides. The mixture was separated and the α-anomer (α-10) was found to be cytotoxic, whereas theβ-anomer (β-10) was inactive. 相似文献
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