2,161 research outputs found

    Rapid Detection of Avian Eimeria Species Using Denaturing Gradient Gel Electrophoresis

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    A denaturing gradient gel electrophoresis (DGGE) assay was developed to rapidly discriminate species of avian Eimeria. Amplification by PCR of the small subunit ribosomal RNA gene (approximately 1,600 nucleotides) with Eimeria genus-specific primers followed by cloning and sequencing allowed us to carry out phylogenetic analyses and identify clone sequences to species level in most cases. Clones were subsequently used to amplify a smaller fragment (approximately 120 nucleotides) suitable for DGGE. The fragments were separated on denaturing gradient gel and bands with unique migration distances were mixed to obtain an identification ladder. The identification ladder and PCR products obtained from DNA extracted from fecal samples from several poultry farms were compared. Applying the DGGE method in this study allowed a rapid differentiation of Eimeria species present in fecal samples collected from poultry farms

    Evolutionary adaptations of ruminants and their potential relevance for modern production systems

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    Comparative physiology applies methods established in domestic animal science to a wider variety of species. This can lead to improved insight into evolutionary adaptations of domestic animals, by putting domestic species into a broader context. Examples include the variety of responses to seasonally fluctuating environments, different adaptations to heat and drought, and in particular adaptations to herbivory and various herbivore niches. Herbivores generally face the challenge that a high food intake compromises digestive efficiency (by reducing ingesta retention time and time available for selective feeding and for food comminution), and a variety of digestive strategies have evolved in response. Ruminants are very successful herbivores. They benefit from potential advantages of a forestomach without being constrained in their food intake as much as other foregut fermenters, because of their peculiar reticuloruminal sorting mechanism that retains food requiring further digestion but clears the forestomach of already digested material; the same mechanism also optimises food comminution. Wild ruminants vary widely in the degree to which their rumen contents ‘stratify', with little stratification in ‘moose-type' ruminants (which are mostly restricted to a browse niche) and a high degree of stratification into gas, particle and fluid layers in ‘cattle-type' ruminants (which are more flexible as intermediate feeders and grazers). Yet all ruminants uniformly achieve efficient selective particle retention, suggesting that functions other than particle retention played an important role in the evolution of stratification-enhancing adaptations. One interesting emerging hypothesis is that the high fluid turnover observed in ‘cattle-type' ruminants - which is a prerequisite for stratification - is an adaptation that not only leads to a shift of the sorting mechanism from the reticulum to the whole reticulo-rumen, but also optimises the harvest of microbial protein from the forestomach. Although potential benefits of this adaptation have not been quantified, the evidence for convergent evolution toward stratification suggests that they must be substantial. In modern production systems, the main way in which humans influence the efficiency of energy uptake is by manipulating diet quality. Selective breeding for conversion efficiency has resulted in notable differences between wild and domestic animals. With increased knowledge on the relevance of individual factors, that is fluid throughput through the reticulo-rumen, more specific selection parameters for breeding could be defined to increase productivity of domestic ruminants by continuing certain evolutionary trajectorie

    Recreational snow-sports injury risk factors and countermeasures: a meta-analysis review and Haddon Matrix Evaluation

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    Background: Snow sports (alpine skiing/snowboarding) would benefit from easily implemented and cost-effective injury prevention countermeasures that are effective in reducing injury rate and severity. Objective: For snow sports, to identify risk factors and to quantify evidence for effectiveness of injury prevention countermeasures. Methods: Searches of electronic literature databases to February 2014 identified 98 articles focused on snow sports that met the inclusion criteria and were subsequently reviewed. Pooled odds ratios (ORs) with 90 % confidence intervals (CIs) and inferences (percentage likelihood of benefit/harm) were calculated using data from 55 studies using a spreadsheet for combining independent groups with a weighting factor based on quality rating scores for effects. Results: More experienced skiers and snowboarders are more likely to sustain an injury as a result of jumps, while beginners sustain injuries primarily as a result of falls. Key risk factors that countermeasure interventions should focus on include, beginner skiers (OR 2.72; 90 % CI 2.15–3.44, 99 % most likely harmful), beginner snowboarders (OR 2.66; 90 % CI 2.08–3.40, 99 % harmful), skiers/snowboarders who rent snow equipment (OR 2.58; 90 % CI 1.98–3.37, 99 % harmful) and poor visibility due to inclement weather (OR 2.69; 90 % CI 1.43–5.07, 97 % harmful). Effective countermeasures include helmets for skiers/snowboarders to prevent head injuries (OR 0.58; 90 % CI 0.51–0.66, 99 % most likely beneficial), and wrist guards for snowboarders to prevent wrist injuries (OR 0.33; 90 % CI 0.23–0.47, 99 % beneficial). Discussion: The review identified key risk factors for snow-sport injuries and evaluated the evidence for the effectiveness of existing injury prevention countermeasures in recreational (general public use of slopes, not racing) snow sports using a Haddon’s matrix conceptual framework for injury causation (host/snow-sport participant, agent/mechanism and environment/community). Conclusion: Best evidence for the effectiveness of injury prevention countermeasures in recreational snow sports was for the use of helmets and wrist guards and to address low visibility issues via weather reports and signage

    Unforgeable Noise-Tolerant Quantum Tokens

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    The realization of devices which harness the laws of quantum mechanics represents an exciting challenge at the interface of modern technology and fundamental science. An exemplary paragon of the power of such quantum primitives is the concept of "quantum money". A dishonest holder of a quantum bank-note will invariably fail in any forging attempts; indeed, under assumptions of ideal measurements and decoherence-free memories such security is guaranteed by the no-cloning theorem. In any practical situation, however, noise, decoherence and operational imperfections abound. Thus, the development of secure "quantum money"-type primitives capable of tolerating realistic infidelities is of both practical and fundamental importance. Here, we propose a novel class of such protocols and demonstrate their tolerance to noise; moreover, we prove their rigorous security by determining tight fidelity thresholds. Our proposed protocols require only the ability to prepare, store and measure single qubit quantum memories, making their experimental realization accessible with current technologies.Comment: 18 pages, 5 figure

    Stochastic model of transcription factor-regulated gene expression

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    We consider a stochastic model of transcription factor (TF)-regulated gene expression. The model describes two genes: Gene A and Gene B which synthesize the TFs and the target gene proteins respectively. We show through analytic calculations that the TF fluctuations have a significant effect on the distribution of the target gene protein levels when the mean TF level falls in the highest sensitive region of the dose-response curve. We further study the effect of reducing the copy number of Gene A from two to one. The enhanced TF fluctuations yield results different from those in the deterministic case. The probability that the target gene protein level exceeds a threshold value is calculated with a knowledge of the probability density functions associated with the TF and target gene protein levels. Numerical simulation results for a more detailed stochastic model are shown to be in agreement with those obtained through analytic calculations. The relevance of these results in the context of the genetic disorder haploinsufficiency is pointed out. Some experimental observations on the haploinsufficiency of the tumour suppressor gene, Nkx3.1, are explained with the help of the stochastic model of TF-regulated gene expression.Comment: 17 pages, 11 figures. Accepted for publication in Physical Biolog

    Why do men self-harm? A literature review

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    This critical review developed and analysed two key strands. One strand examined the reasons why men self-harm; the other examined effective ways to educate staff about self-harm. These strands were interweaved to develop an in-depth and informative review to help educate and inform staff who work with and support men who self-harm. A systematic search strategy was conducted to find primary research articles for analysis and evaluation. Three key themes emerged: interpersonal relationships; attitudes and educating staff. This review recommends that staff should be encouraged to change their behaviour and view themselves and their relationships differently. This can have a positive impact on developing and maintaining therapeutic relationships

    Opposing actions of c-ets/PU.1 and c-myb protooncogene products in regulating the macrophage-specific promoters of the human and mouse colony-stimulating factor-1 receptor (c-fms) genes

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    The receptor for macrophage colony stimulating factor (CSF-1), the c- fms gene product, is a key determinant in the differentiation of monocytic phagocytes. Dissection of the human and mouse c-fms proximal promoters revealed opposing roles for nuclear protooncogenes in the transcriptional regulation of this gene. On the one hand, c-ets-1, c- ets-2, and the macrophage-specific factor PU.1, but not the ets-factor PEA3, trans-activated the c-fms proximal promoter. On the other hand c- myb repressed proximal promoter activity in macrophages and blocked the action of c-ets-1 and c-ets-2. Basal c-fms promoter activity was almost undetectable in the M1 leukaemia line, which expressed high levels of c- myb, but was activated as cells differentiated in response to leukemia inhibitory factor and expressed c-fms mRNA. The repressor function of c- myb depended on the COOH-terminal domain of the protein. We propose that ets-factors are necessary for the tissue-restricted expression of c-fms and that c-myb acts to ensure correct temporal expression of c- fms during myeloid differentiation

    Seroepidemiologi Nipah Virus Pada Kalong Dan Ternak Babi Di Beberapa Wilayah Di Indonesia

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    Nipah Virus Seroepidemiology in Flying Fox and Pig Husbandry in Several Areasof Indonesia. Nipah is a dangerous zoonotic disease which was carried by flying fox.The disease had been occurred in Malaysia in 1999 and infect pigs and caused humandeath. Indonesia is adjacent country to Malaysia, hence, a serological study had beenconducted on 156 flying fox (P. vampyrus) sera from North Sumatera, West Java, CentralJava and East Java. Besides that, 2740 pig sera was randomly collected in differentprovinces to detect Nipah infection. Both flying fox and pig sera were tested usingELISA test to detect the presence of Nipah antibody. The results indicated that 37 from156 flying fox sera (23.7%) has antibodies against Nipah virus. Infections were occuredin all sampling sites with the prevalence varied from 18% to 33 %. Meanwhile, no pigsera tested (2740) had antibody against Nipah virus. Based on these results it can beconcluded that Nipah virus infections were occurred in flying fox in some parts inIndonesia, but not in pigs. It was suggested that the presence of Nipah virus in Indonesiashould be anticipated. Hence the distribution of its infection in pigs and human must beanticipated. Monitoring of Nipah infection in areas adjacent to Malaysia must be increasedto detect the entering of the disease in Indonesia
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