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121.
  1. A central theme for conservation is understanding how animals differentially use, and are affected by change in, the landscapes they inhabit. However, it has been challenging to develop conservation schemes for habitat‐specific behaviors.
  2. Here we use behavioral change point analysis to identify behavioral states of golden eagles (Aquila chrysaetos) in the Sonoran and Mojave Deserts of the southwestern United States, and we identify, for each behavioral state, conservation‐relevant habitat associations.
  3. We modeled behavior using 186,859 GPS points from 48 eagles and identified 2,851 distinct segments comprising four behavioral states. Altitude above ground level (AGL) best differentiated behavioral states, with two clusters of short‐distance movement behaviors characterized by low AGL (state 1 AGL = 14 m (median); state 2 AGL = 11 m) and two associated with longer‐distance movement behaviors and characterized by higher AGL (state 3 AGL = 108 m; state 4 AGL = 450 m).
  4. Behaviors such as perching and low‐altitude hunting were associated with short‐distance movements in updraft‐poor environments, at higher elevations, and over steeper and more north‐facing terrain. In contrast, medium‐distance movements such as hunting and transiting were over gentle and south‐facing slopes. Long‐distance transiting occurred over the desert habitats that generate the best updraft.
  5. This information can guide management of this species, and our approach provides a template for behavior‐specific habitat associations for other species of management concern.
  相似文献   
122.

Background

Exposure to multiple forms of violence, including abuse and crime is termed poly-victimisation. There has been increasing research interest in poly-victimisation among children and adolescents in high income countries. However, experiences among adolescents living in low- and lower-middle-income countries are yet to be examined.

Aims

To establish the prevalence of lifetime exposure to poly-victimisation and demographic characteristics of victims among high school students in Vietnam.

Methods

A cross-sectional survey with a self-report, anonymous questionnaire was conducted in ten high schools in Hanoi, Vietnam between October 2013 and January 2014. Poly-victimisation was assessed using the Juvenile Victimisation Questionnaire Revised 2 (JVQ R2).

Results

A total of 1,606/1,745 (92.0%) eligible students provided data and were included in the analyses. Lifetime exposure to at least one form of victimisation was reported by 94.3% (95%CI: 92.5-95.4%) of participants and lifetime exposure to more than 10 forms by 31.1% (95%CI: 27.8-33.5%). Poly-victimisation was associated with experiencing more adverse life events, having a chronic disease or disability, living with a step-parent, experiencing family life as unhappy, being disciplined at school, and living in a rural area. Poly-victimisation experiences differed among students from the three types of high schools in Vietnam.

Conclusions

These data reveal the prevalence and multi-factorial risks of exposure to poly-victimisation among adolescents in Vietnam. Prevalence rates of different forms of victimisation among Vietnamese students, including those previously un-investigated, were higher than those reported in other settings. Poly-victimisation was also common among them. There were certain subgroups who were more vulnerable to poly-victimisation. Further research to understand the broader aspects of adolescence in Vietnam, including poly-victimisation, is thus recommended. Special attention should be paid to specific subgroups in the prevention of violence against children and adolescents in this setting. Education to raise awareness about poly-victimisation among the community is needed.  相似文献   
123.
124.
Pulmonary surfactant lowers surface tension in the lung. Its deficiency leads to the severe physiologic abnormalities seen in the respiratory distress syndrome. The hydrophobic surfactant proteins, SP-B and SP-C, appear to be especially important in the surface-spreading characteristics of pulmonary surfactant. We report the nucleotide sequence of cDNA clones for rat SP-C and compare the deduced amino acid sequence for SP-C from several species. A highly conserved domain exists within the confines of mature human SP-C. An Eisenberg plot of this region predicts a membrane-associated helix. We also demonstrate by Northern analysis the tissue-specific expression of SP-C. A comparison of signal strength between total lung RNA and RNA derived from isolated type II cells supports the idea that most SP-C messenger RNA in total lung can be accounted for by that present in alveolar type II cells.  相似文献   
125.
We have identified a strain of polyomavirus, Py(L), which is unusual in causing acute morbidity and early death after inoculation of newborn mice. We determined that these animals died of kidney failure associated with extensive, virus-mediated destruction of renal tissue. Interestingly, the Py(L) strain infects baby mouse kidney cell cultures more efficiently than do other strains.  相似文献   
126.
Compounds 10a-10d and 10i are very potent inhibitors of Eimeria tenella cGMP-dependent protein kinase (0.081-0.32 nM) and are very efficacious antiparasitic agents in vivo when administered to chickens at 12.5-25 ppm levels in the feed.  相似文献   
127.
BACKGROUND: We report on the potential DNA binding modes and spectral characteristics of the cell-permeant far red fluorescent DNA dye, DRAQ5, in solution and bound within intact cells. Our aim was to determine the constraints for its use in flow cytometry and bioimaging. METHODS: Solution characteristics and quantum yields were determined by spectroscopy. DRAQ5 binding to nuclear DNA was analyzed using fluorescence quenching of Hoechst 33342 dye, emission profiling by flow cytometry, and spectral confocal laser scanning microscopy of the complex DRAQ5 emission spectrum. Cell cycle profiling utilized an EGFP-cyclin B1 reporter as an independent marker of cell age. Molecular modeling was used to explore the modes of DNA binding. RESULTS: DRAQ5 showed a low quantum yield in solution and a spectral shift upon DNA binding, but no significant fluorescence enhancement. DRAQ5 caused a reduction in the fluorescence intensity of Hoechst 33342 in live cells prelabeled with the UV excitable dye, consistent with molecular modeling that suggests AT preference and an engagement of the minor groove. In vivo spectral analysis of DRAQ5 demonstrated shifts to longer wavelengths upon binding with DNA. Analysis of spectral windows of the dual emission peaks at 681 and 707 nm in cells showed that cell cycle compartment recognition was independent of the far red-near IR emission wavelengths monitored. CONCLUSIONS: The study provides new clues to modes of DNA binding of the modified anthraquinone molecule in vivo, and its AT base-pair selectivity. The combination of low quantum yield but high DNA affinity explains the favorable signal-to-noise profile of DRAQ5-nuclear fluorescence. The robust nature of cell cycle reporting using DRAQ5, even when restricted spectral windows are selected, facilitates the analysis of encroaching spectral emissions from other fluorescent reporters, including GFP-tagged proteins.  相似文献   
128.
The possible existence of GABA-transmitter neurons in the lower auditory system of the guinea pig has been investigated by means of three different experimental approaches: (1) the regional distribution of GABA and its related enzymes, (2) the subcellular distribution of glutamate decarboxylase, and (3) the effect of selected nerve lesions on glutamate decarboxylase concentrations in the auditory nuclei. Within the regions investigated considerable variations in glutamate decarboxylase activity and GABA concentration were found, with the highest values observed in the inferior colliculus. The dorsal cochlear nucleus also contained significant amounts of both glutamate decarboxylase and GABA, in addition to high concentrations of GABA transaminase. The subcellular distribution of glutamate decarboxylase was bimodal in both the cochlear nucleus and inferior colliculus with most enzyme activity recovered in the soluble and synaptosomal fractions. Neither end organ (cochlea) nor trapezoid body lesions induced a significant loss of glutamate decarboxylase activity in either the cochlear nucleus or inferior colliculus. The results suggest the presence of short axon GABAergic interneurons in the cochlear nucleus, most of which appear to terminate within the dorsal cochlear nucleus.  相似文献   
129.
Arenaviruses are one of the largest families of human hemorrhagic fever viruses and are known to infect both mammals and snakes. Arenaviruses package a large (L) and small (S) genome segment in their virions. For segmented RNA viruses like these, novel genotypes can be generated through mutation, recombination, and reassortment. Although it is believed that an ancient recombination event led to the emergence of a new lineage of mammalian arenaviruses, neither recombination nor reassortment has been definitively documented in natural arenavirus infections. Here, we used metagenomic sequencing to survey the viral diversity present in captive arenavirus-infected snakes. From 48 infected animals, we determined the complete or near complete sequence of 210 genome segments that grouped into 23 L and 11 S genotypes. The majority of snakes were multiply infected, with up to 4 distinct S and 11 distinct L segment genotypes in individual animals. This S/L imbalance was typical: in all cases intrahost L segment genotypes outnumbered S genotypes, and a particular S segment genotype dominated in individual animals and at a population level. We corroborated sequencing results by qRT-PCR and virus isolation, and isolates replicated as ensembles in culture. Numerous instances of recombination and reassortment were detected, including recombinant segments with unusual organizations featuring 2 intergenic regions and superfluous content, which were capable of stable replication and transmission despite their atypical structures. Overall, this represents intrahost diversity of an extent and form that goes well beyond what has been observed for arenaviruses or for viruses in general. This diversity can be plausibly attributed to the captive intermingling of sub-clinically infected wild-caught snakes. Thus, beyond providing a unique opportunity to study arenavirus evolution and adaptation, these findings allow the investigation of unintended anthropogenic impacts on viral ecology, diversity, and disease potential.  相似文献   
130.
Three mutant mice with pigmentation phenotypes were recovered from a genomewide random mouse chemical mutagenesis study. White toes (Whto; MGI:1861986), Belly spot and white toes (Bswt; MGI:2152776) and Dark footpads 2 (Dfp2; MGI:1861991) were identified following visual inspection of progeny from a male exposed to the point mutagen ethylnitrosourea (ENU). In order to rapidly localize the causative mutations, genome-wide linkage scans were performed on pooled DNA samples from backcross animals for each mutant line. Whto was mapped to proximal mouse chromosome (Mmu) 7 between Cen (the centromere) and D7Mit112 (8.0 cM from the centromere), Bswt was mapped to centric Mmul between D1Mit214 (32.1 cM) and D1Mit480 (32.8 cM) and Dfp2 was mapped to proximalMmu4 between Cen and D4Mit18 (5.2 cM). Whto, Bswt and Dfp2 may provide novel starting points in furthering the elucidation of genetic and biochemical pathways relevant to pigmentation and associated biological processes.  相似文献   
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