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91.
Research is often an essential component of completing a veterinary medicine degree, with universities worldwide aiming to teach students a variety of techniques and general research comprehension and skills. As universities worldwide navigated the COVID-19 pandemic, it was often necessary to move towards distance learning, this was employed for the research module at The University of Nottingham, School of Veterinary Medicine and Science. Following completion of their independent research project, each student cohort was sent a student evaluation of the module questionnaire and quantitative and qualitative analysis was undertaken. In addition, assessment outcomes based on dissertation grade, supervisor grade and overall module score were analysed quantitatively. This was conducted on both the individual cohorts and between the pre- and peri-pandemic groups, ranging from 2017–2018 through to 2021–2022 cohorts. The students received increased dissertation and supervisor grades (by nearly 6%) during the 2021–2022 peri-pandemic cohort, when compared to the pre-pandemic cohorts, but did differ significantly compared to the 2020–2021 cohort. The pre- and peri-pandemic Likert-scale ratings for module organisation and assessment criteria were similar, workload management and the ability to explore concepts and ideas was reduced in the peri-pandemic cohorts, whereas the accessibility to resources was increased in the peri-pandemic students compared to those taught prior to the pandemic. Student feedback can provide essential information when designing and managing research projects and when compared to assessment grades it can help us understand attainment, essential information when providing a quality university level education whilst supporting student welfare following the COVID-19 pandemic.  相似文献   
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93.
Results of two field experiments, one on SA 1 pigeonpea in rainfed and the other on Co.5 pigeonpea in irrigated conditions revealed thatBacillus thuringiensis var.kurstaki (B.t.k.) (Delfin), its combinations with nuclear polyhedrosis virus ofHeliothis armigera andChrysoperla carnea were as effective as endosulfan in reducing the pod borers,Heliothis armigera andExelastis atomosa. However,B.t.k. 1.25 kg+endosulfan 175 g/ha orB.t.k. 2.5 kg+HaNPV, 250 LE/ha gave better control of damage to flowers and pods thanB.t.k. applied alone on SA 1 pigeonpea. The yield differences between these treatments were not significant. A combination of HaNPV 250 LE/ha+endosulfan 175 g/ha was superior toB.t.k. Similar trend was seen on Co.5 pigeonpea. Release ofC. carnea second instar larvae 1 lakh/ha was not effective in increasing the yield of pigeonpea.  相似文献   
94.
Ten fruit and kernel traits were measured in 152 Irvingia gabonensis and 293 Dacryodes edulis trees from 6 villages in Cameroon and Nigeria. Frequency distribution curves were used to examine the range of variation of each trait of each species in each village and aggregated into national and regional populations. There were differences between the village sub-populations, with regard to the normality (e.g., mean kernel mass of D. edulis) or skewness (e.g., mean flesh depth of D. edulis) of the distribution curves and in the degree of separation between the individual village populations along the x axis, resulting in the development of a bimodal distribution in the regional population. For all traits, populations of both species differed significantly between countries, but only in D. edulis were there significant differences between the Cameroon populations. On the basis of the results of this study, D. edulis can be said to be virtually wild in Nigeria but semi-domesticated in Cameroon, while I. gabonensis is wild in Cameroon and semi-domesticated in Nigeria. These results are discussed with regard to a hypothesis that the range and frequency of variation in the different populations can be used to identify five stages of domestication. From a comparison of the frequency distribution curves of desirable versus undesirable traits, and statistically identifyable changes in skewness and kurtosis, it is concluded that as a result of the farmers’ own efforts by truncated selection, D. edulis is between Stages 2 and 3 of domestication (with a 67% relative gain in flesh depth) in Cameroon, while I. gabonensis in Nigeria is at Stage 2 (with a 44% relative gain in flesh depth). In this study, genetic diversity seems to have been increased, and not reduced, by domestication. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
95.
建造一座木材工业生产厂是需要达到一系列的国家立法要求。而达到这些要求是通过严格的科学研究和调查而得来的。在一个项目中,通常这是一个关键环节。大多高度工业化国家都具有严格的法律条例控制放射性粉尘和气体对环境所造成的污染。本文讨论的是在木材工业干燥过程的内部,什么是造成环境污染的环节因素,以化工生产条件所带来的影响为例,输入原材料的选择,干燥炉的设计,运作程序,以及燃料的选择。上述因素将会对烟囱污染带来什么样的影 响?本文采用国际通用的分析手法,准确地分析了放射性粉尘积累以及如何控制由此造成的空气污染。根据研究调查的积累进一步探讨如何以最佳的设计系统而达到控制污染。以冷凝缩代替热干燥将是一个新的值得考虑的工业化革新。参14。  相似文献   
96.
OBJECTIVE: To describe the pattern and prevalence of food and drink advertisements to children on commercial television in Sydney, Australia, and compare these with advertising regulations set out in the Children's Television Standards and results from a similar study in 2002. DESIGN: Data were collected by recording television from 06.00 hours until 23.00 hours on all three commercial channels from Sunday 14 May 2006 to Saturday 20 May 2006 (357 h). The study analysed advertisements in two children's viewing periods, one as defined in the 2002 study and the other according to current standards. Food advertisements were coded using 18 food categories and were analysed by time period and popular children's programmes. RESULTS: Food advertisements occurred in similar proportions during children's viewing hours and adult's viewing hours (25.5 vs. 26.9% of all advertisements, respectively), although there was a higher rate of high-fat/high-sugar food advertisements during children's viewing hours (49 vs. 39% of all food advertisements, P < 0.001). There were even more advertisements for high-fat/high-sugar foods during popular children's programmes, contributing to 65.9% of all food advertisements. Estimates of exposure indicate that children aged 5-12 years were exposed to 96 food advertisements, including 63 high-fat/high-sugar advertisements per week. Since 2002, there has been a reduction in overall food and high-fat/high-sugar food advertisements.CONCLUSION: Despite reductions in overall levels of food advertising, children continue to experience high levels of exposure to food advertisements, which remain skewed towards unhealthy foods. Further food advertising regulation should be required to curtail the current levels of advertising of high-fat/high-sugar foods to children, to make them commensurate with recommended levels of consumption.  相似文献   
97.
98.
During an experimental infection of sheep with Fasciola hepatica or F. gigantica, MM3-SERO and MM3-COPRO ELISA tests were applied to compare the kinetics of antibody production and coproantigen release between the 2nd and 32nd week post-infection (wpi). The Kato-Katz technique was used to measure the kinetics of egg shedding by both Fasciola species (eggs per gram of feces, epg). The kinetics of IgG antibodies for all sheep infected with F. hepatica and F. gigantica followed a similar pattern. Optical density (OD) increased rapidly between the 4th until the 12th wpi, when the highest values were reached and then decreased slowly until the 32nd wpi. Coproantigen levels increased above the cut-off value between 6 and 9 wpi in the F. hepatica group, and between 9 and 11 wpi in the F. gigantica group. The comparison between coproantigen levels and epg indicated that F. hepatica-infected sheep had detectable amounts of coproantigens 4–7 weeks before patency (egg shedding), while F. gigantica-infected sheep had detectable amounts of coproantigens 3–6 weeks before patency. When comparing the kinetics of coproantigen release vs the kinetics of epg, a similar pattern emerged, but with a two-week time-lag in epg, for both F. hepatica and F. gigantica infections. The amount of coproantigen release by each adult was not burden dependent for F. hepatica infection (burden of 33–66 adults), while it was for F. gigantica infection (burden of 17–69 adults). The results demonstrate the usefulness of the MM3-SERO and MM3-COPRO ELISAs as tools for the diagnosis of early as well as long-term fascioliasis infections, and suggest that they can potentially be applied to human fascioliasis even in countries where F. hepatica and F. gigantica co-exist. These tests can be employed not only in the diagnosis, but also in studies on epidemiology as well as pathogenesis and treatment in animals and humans since they allow post-treatment infection monitoring.  相似文献   
99.
Sixty-two persistently colonising Campylobacter jejuni strains were tested for their ability to dominate colonisation of the chicken gastrointestinal tract in competition with each other leading to selection of dominant or "hyper-colonising"Campylobacter strains, which are able to displace others in the chicken intestinal tract. One such strain was shown to be a hyper-efficient coloniser of chickens, as it was able to displace other colonising strains, as well as maintain itself in the chicken intestinal tract for the duration of the 56-day broiler production cycle. Once colonisation was established, this hyper-colonising C. jejuni strain, 331, could not be displaced by other colonising or hyper-colonising strains. We proposed that a defined, hyper-colonising strain, or a cocktail of defined strains with a similar phenotype, could form the basis for biological control of unknown/uncharacterised Campylobacter strains from the environment that continuously colonise chicken flocks. To validate this approach, three different chicken infection trials were carried out. These trials demonstrated that the dominant strain of C. jejuni was able to colonise broiler chickens consistently and for the entire life of the birds irrespective of the day of inoculation and antimicrobial agents used in the feed to control other pathogenic micro-organisms. In addition, we have shown that the bio-control strain was able to replace other colonising strains at various points of a 56-day broiler production cycle irrespective of time and type of inoculation. This strain was also capable of re-establishing itself following the challenge with other strains, with and without re-challenge. This work represents a "proof of principle" that a defined C. jejuni strain could be used to biologically control circulation of uncharacterised environmental strains in commercial poultry flocks.  相似文献   
100.
We assessed home range size for breeding loggerhead turtles (Caretta caretta) near the limit of the species range at the Greek island of Zakynthos in the Mediterranean. Thirteen adult females and seven adult males were tracked using GPS units (loggers and transmitters) during May and June of 2006, 2007 and 2008. Kernel analysis indicated that core home range sizes (50% estimator; range: 2.9-19.7 km2) for both males and females were restricted to a 7.5 km tract of coastline. 15% of GPS locations fell outside of the national park protection zones, while within the protected breeding area 88% of GPS locations occurred in zones of minimal protection. Female home ranges were 64% larger in 2008 than in 2006 and 2007, indicating that several years monitoring may be required for the most effective designation of marine protected areas (MPAs). Ten of the tracked females departed the core breeding area on 15 occasions for periods of 1-15 days travelling distances of 10-100 km, although none nested at alternative breeding sites. The inter-annual variability of breeding area home range size and likelihood of incidence of forays appeared be correlated with barometric pressure. The movement responses of loggerheads to environmental conditions implicates an ability to switch nesting areas over small scales in response to climate change. However, such behaviour suggests the protection of existing core breeding sites may be inadequate, with policy makers being required to consider the protection of broader areas to encompass potential changes in the habitat needs of this species.  相似文献   
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