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Analysis of the costs of veterinary education and factors associated with financial stress among veterinary students in Australia 
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下载免费PDF全文 Objective
To investigate the course‐related and other costs involved in obtaining a veterinary education in Australia and how these costs are met. The study also aimed to identify sociodemographic and course‐related factors associated with increased financial stress.Methods
Students from seven Australian veterinary schools were surveyed using an online questionnaire. A total of 443 students participated (response rate 17%). Responses to survey items relating to finances, employment and course‐related costs were compared with sociodemographic factors and prior research in the area of student financial stress.Results
Respondents reported spending a median of A$300 per week on living costs and a median of A$2,000 per year on course‐related expenses. Over half of respondents received the majority of their income from their parents or Youth Allowance (56%). A similar proportion (55%) reported that they needed to work to meet basic living expenses. Circumstances and sociodemographic factors linked to perceived financial stress included requiring additional finances to meet unexpected costs during the course; sourcing additional finances from external loans; an expected tuition debt at graduation over A$40,000; being 22 years or older; working more than 12 hours per week; living costs above A$300 per week; and being female.Conclusion
The costs involved in obtaining a veterinary education in Australia are high and over half of respondents are reliant on parental or Government income support. Respondents with certain sociodemographic profiles are more prone to financial stress. These findings may have implications for the psychological health, diversity and career plans of veterinary students in Australia. 相似文献33.
Patterns of mortality in a cold-climate population of garter snakes (Thamnophis sirtalis parietalis)
The causes, magnitude and phenotypic determinants of mortality are central features of population demography. Although critical to effective conservation planning, these attributes remain poorly understood for most wild vertebrates. Exceptionally dense aggregations of garter snakes (Thamnophis sirtalis parietalis) in and around communal overwintering dens in central Manitoba provide an exceptional opportunity to enumerate these factors. Over the course of long-term field studies we obtained data on mortality of snakes in autumn as they migrated back from their summer ranges, and in winter during and after their entry into the underground dens. Some mortality sources were affected by a snake's phenotype: for example, snakes killed by motor vehicles were smaller, on average, than surviving snakes. However, two major episodes of mortality at the dens themselves (freezing during midwinter due to atypically light snow cover; and drowning due to flooding after heavy rains late in autumn) were essentially random with respect to phenotype. Mark-recapture estimates suggest that the winterkill event eliminated >60,000 snakes, comprising almost the entire populations of the three largest dens. Although such events are cryptic because the bodies of frozen animals remain underground, they are of much greater magnitude than overt mortality sources for active snakes (roadkills, predation, etc.). Thus, relatively minor habitat manipulations around the dens may contribute more to conservation of these populations than would extensive efforts to protect active snakes during their spring and autumn migrations. 相似文献
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The flight of the Solar Optical Universal Polarimeter on Spacelab-2 provided the opportunity for the collection of time sequences of diffraction-limited (0.5 are second) solar images with excellent pointing stability (0.003 are second) and with freedom from the distortion that plagues ground-based images. A series of white-light images of active region 4682 were obtained on 5 August 1985, and the area containing the sunspot has been analyzed. These data have been digitally processed to remove noise and to separate waves from low-velocity material motions. The results include (i) proper motion measurements of a radial outflow in the photospheric granulation pattern just outside the penumbra; (ii) discovery of occasional bright structures ("streakers") that appear to be ejected outward from the penumbra; (iii) broad dark "clouds" moving outward in the penumbra, in addition to the well-known bright penumbral grains moving inward; (iv) apparent extensions and contractions of penumbral filaments over the photosphere; and (v) observation of a faint bubble or looplike structure that seems to expand from two bright penumbral filaments into the photosphere. 相似文献
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土壤缓慢脱水对冬小麦渗透调节,光合作用和膜脂过氧化的影响 总被引：1，自引：0，他引：1
两个小麦品种叶片渗透调节能力随土壤缓慢脱水而增加，昌乐５号约为０．２９ＭＰａ，鲁麦５号约为０．１９ＭＰａ。随着土壤脱水的加剧，光合作用受抑制的原因有一个从气孔限制向叶肉细胞光合活性限制的转变过程。渗透调节对干旱条件下光合作用的维持和供水后光合作用的恢复都有一定的贡献。用改良法测定两二醇含量，结果表明，抗旱品种昌乐５号的丙二醇含量没有增加，这与其内源保护酶（ＳＯＤ）活性在严重干旱条件下较高有关。相反，鲁麦５号在严重干旱条件下由于其ＳＯＤ酶活性下降，丙二醇含量显著高于对照，表明发生了膜脂过氧化。 相似文献
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Shibata K Nakamura T Matsumoto T Otsuji K Okamoto TJ Nishizuka N Kawate T Watanabe H Nagata S Ueno S Kitai R Nozawa S Tsuneta S Suematsu Y Ichimoto K Shimizu T Katsukawa Y Tarbell TD Berger TE Lites BW Shine RA Title AM 《Science (New York, N.Y.)》2007,318(5856):1591-1594
The heating of the solar chromosphere and corona is a long-standing puzzle in solar physics. Hinode observations show the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions. They are typically 3 to 7 arc seconds = 2000 to 5000 kilometers long and 0.2 to 0.4 arc second = 150 to 300 kilometers wide, and their velocity is 10 to 20 kilometers per second. These small jets have an inverted Y-shape, similar to the shape of x-ray anemone jets in the corona. These features imply that magnetic reconnection similar to that in the corona is occurring at a much smaller spatial scale throughout the chromosphere and suggest that the heating of the solar chromosphere and corona may be related to small-scale ubiquitous reconnection. 相似文献
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Sequence and expression of human estrogen receptor complementary DNA 总被引：95，自引：0，他引：95
G L Greene P Gilna M Waterfield A Baker Y Hort J Shine 《Science (New York, N.Y.)》1986,231(4742):1150-1154
The mechanism by which the estrogen receptor and other steroid hormone receptors regulate gene expression in eukaryotic cells is not well understood. In this study, a complementary DNA clone containing the entire translated portion of the messenger RNA for the estrogen receptor from MCF-7 human breast cancer cells was sequenced and then expressed in Chinese hamster ovary (CHO-K1) cells to give a functional protein. An open reading frame of 1785 nucleotides in the complementary DNA corresponded to a polypeptide of 595 amino acids and a molecular weight of 66,200, which is in good agreement with published molecular weight values of 65,000 to 70,000 for the estrogen receptor. Homogenates of transformed Chinese hamster ovary cells containing a protein that bound [3H]estradiol and sedimented as a 4S complex in salt-containing sucrose gradients and as an 8 to 9S complex in the absence of salt. Interaction of this receptor-[3H]estradiol complex with a monoclonal antibody that is specific for primate ER confirms the identity of the expressed complementary DNA as human estrogen receptor. Amino acid sequence comparisons revealed significant regional homology among the human estrogen receptor, the human glucocorticoid receptor, and the putative v-erbA oncogene product. This suggests that steroid receptor genes and the avian erythroblastosis viral oncogene are derived from a common primordial gene. The homologous region, which is rich in cysteine, lysine, and arginine, may represent the DNA-binding domain of these proteins. 相似文献
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Specific pathways of the ecological impact of invasive species remain poorly known. Although the spread of toxic cane toads (Bufo marinus) through tropical Australia is widely believed to have caused extensive mortality of native reptiles and mammals, effects of toad ingestion on native anurans have been virtually ignored. Our studies on the Adelaide River floodplain show that the most numerous vertebrate victims of toad invasion are native tadpoles that die when they attempt to consume toad eggs. We documented 11 episodes of mass mortality, totalling >1300 tadpoles of 10 species, in five waterbodies within a single wet-season shortly after the toads invaded. A causal link between toad breeding and tadpole mortality is supported by observations that: (1) in at least 9 of the 11 waterbodies involved, toads bred immediately prior to mortality events; (2) water quality was indistinguishable from that of control ponds, and tadpoles placed in that water remained healthy; (3) dead tadpoles showed no sign of disease; and (4) laboratory trials showed rapid, 100% mortality in native tadpoles exposed to freshly-laid toad eggs. Despite these high mortality rates, toad invasion does not appear to threaten the viability of anuran populations because frogs often breed in ponds not used by toads, and because density-dependent growth and survival within tadpole communities mean that additional mortality may not reduce the total effective recruitment of metamorph frogs from a waterbody. 相似文献