5,129 research outputs found

    Signalment risk factors for cutaneous and renal glomerular vasculopathy (Alabama rot) in dogs in the UK

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    Seasonal outbreaks of cutaneous and renal glomerular vasculopathy (CRGV) have been reported annually in UK dogs since 2012, yet the aetiology of the disease remains unknown. The objectives of this study were to explore whether any breeds had an increased or decreased risk of being diagnosed with CRGV, and to report on age and sex distributions of CRGV cases occurring in the UK. Multivariable logistic regression was used to compare 101 dogs diagnosed with CRGV between November 2012 and May 2017 with a denominator population of 446,453 dogs from the VetCompass database. Two Kennel Club breed groups—hounds (odds ratio (OR) 10.68) and gun dogs (OR 9.69)—had the highest risk of being diagnosed with CRGV compared with terriers, while toy dogs were absent from among CRGV cases. Females were more likely to be diagnosed with CRGV (OR 1.51) as were neutered dogs (OR 3.36). As well as helping veterinarians develop an index of suspicion for the disease, better understanding of the signalment risk factors may assist in the development of causal models for CRGV and help identify the aetiology of the disease

    Investigation of Damper Valve Dynamics Using Parametric Numerical Methods

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    The objectives of this study are to identify the dynamics of a Tenneco Automotive hydraulic damper valve and to predict valve performance. Accurate simulations of damper valve performance can be used to improve valve designs without the expense of physical testing. The Tenneco damper valve consists of thin shims and a spring preloaded disc that restricts fluid from exiting the main flow orifices. The deflection of the shims and spring are dependent on the flow-rate through the valve. The pressure distribution acting on the deformable valve components is investigated numerically using a dynamic modelling technique. This technique involves sequential geometry and simulation updating, while varying both the geometry and flow-rate. The valve deflection is calculated by post-processing the pressure distribution. Valve performance can be predicted by coupling the valve deflection with CFD pressure results

    Epidemiology of diabetes mellitus among 193,435 cats attending primary-care veterinary practices in England

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    BACKGROUND: Diabetes mellitus (DM) is a common endocrine disease of cats. The prevalence of DM in cats in England is not well‐defined. HYPOTHESIS/OBJECTIVES: To estimate the prevalence and identify risk factors for DM in a large population of cats attending primary‐care practices. ANIMALS: A cohort of 193,563 cats in the VetCompass Programme attending 118 primary‐care practices in England. METHODS: Cross‐sectional analysis of cohort clinical data. Data were extracted covering September 1st 2009 and August 31st 2014. Period prevalence of DM was calculated. Associations between risk factors and DM were assessed using logistic regression modelling. RESULTS: Of 1,128 DM cases were identified among 194,563 cats (period prevalence 0.58%; 95% confidence interval [CI] 0.54–0.61). Multivariable modelling indicated that Tonkinese (OR 4.1; 95% CI 1.8–9.6; P = .001), Norwegian Forest (odds ratio [OR] 3.5; 95% CI 1.3–9.6; P = .001) and Burmese (OR 3.0; 95% CI 2.0–4.4; P < .001) cats had increased odds of DM compared with crossbred cats. DM odds increased as bodyweight categories increased above 4 kg (P < .001), as cats aged beyond 6 years old (P < .001) and in insured cats (OR 2.0; 95% CI 1.6–2.4; P < .001) but sex was not significantly associated with DM. CONCLUSIONS AND CLINICAL IMPORTANCE: Diabetes mellitus is an important component of the primary‐care practice caseload with 1‐in‐200 cats affected. An increased risk of DM in certain cat breeds supports a genetic predisposition. These results can guide future research and preventative healthcare

    Infection with a Virulent Strain of Wolbachia Disrupts Genome Wide-Patterns of Cytosine Methylation in the Mosquito Aedes aegypti

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    BACKGROUND Cytosine methylation is one of several reversible epigenetic modifications of DNA that allow a greater flexibility in the relationship between genotype and phenotype. Methylation in the simplest models dampens gene expression by modifying regions of DNA critical for transcription factor binding. The capacity to methylate DNA is variable in the insects due to diverse histories of gene loss and duplication of DNA methylases. Mosquitoes like Drosophila melanogaster possess only a single methylase, DNMT2. DESCRIPTION Here we characterise the methylome of the mosquito Aedes aegypti and examine its relationship to transcription and test the effects of infection with a virulent strain of the endosymbiont Wolbachia on the stability of methylation patterns. CONCLUSION We see that methylation in the A. aegypti genome is associated with reduced transcription and is most common in the promoters of genes relating to regulation of transcription and metabolism. Similar gene classes are also methylated in aphids and honeybees, suggesting either conservation or convergence of methylation patterns. In addition to this evidence of evolutionary stability, we also show that infection with the virulent wMelPop Wolbachia strain induces additional methylation and demethylation events in the genome. While most of these changes seem random with respect to gene function and have no detected effect on transcription, there does appear to be enrichment of genes associated with membrane function. Given that Wolbachia lives within a membrane-bound vacuole of host origin and retains a large number of genes for transporting host amino acids, inorganic ions and ATP despite a severely reduced genome, these changes might represent an evolved strategy for manipulating the host environments for its own gain. Testing for a direct link between these methylation changes and expression, however, will require study across a broader range of developmental stages and tissues with methods that detect splice variants.This research was supported by The National Health and Medical Research Council of Australia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Relativistic inflow in the Seyfert 1 Mrk 335 revealed through X-ray absorption

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    The analysis of hard X-ray features in XMM-Newton data of the bright Sy 1 galaxy Mrk 335 is reported here. The presence of a broad, ionised iron K alpha emission line in the spectrum, first found by Gondoin et al.(2002), is confirmed. The broad line can be modeled successfully by relativistic accretion disc reflection models. Regardless of the underlying continuum we report, for the first time in this source, the detection of a narrow absorption feature at the rest frame energy of ~5.9 keV. If the feature is identified with a resonance absorption line of iron in a highly ionised medium, the redshift of the line corresponds to an inflow velocity of ~0.11-0.15 c. Preliminary results from a longer (100ks) exposure are also presented

    Local perspectives on weirs in the Upper Nepean

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    The Independent Expert Panel of the HawkesburyâNepean River Management Forum commissioned the Institute for Sustainable Futures to conduct research into the values held by river users and community members in relation to the weirs on the Upper Nepean River and concerns they would have with any change to the current situation. The weirs at the centre of this research are Bergins, Thurns, Sharpes and Brownlow Hill. The research questions guiding the project are: What is the nature of the social and economic relationship between people and weirs at a local level In what ways would people want to participate in decisions about the weirs and river management Local people were asked about how they use the weirs, what value they see the weirs having for their community, culture and industry and what concerns there may be about potential changes. The research aims to help the Expert Panel and the Forum make appropriate decisions about potential retention, modification or removal of the weirs and the fishways associated with them. A further aim is to facilitate public participation in the decision-making process. Within any community, there are different individuals and groups with diverse interests and experiences. These differences might result in multiple perspectives between and within groups. To differentiate some of these perspectives, the broader community was divided into four sectors: general public, community groups, identifiable water users such as irrigators and recreational users and Indigenous groups. The general public participants emphasised the aesthetic and leisure value of the river. They appear to identify very strongly with the river, with participants interpreting the existence of the weirs as integral to both the riverâs survival and the ongoing economic survival of the region. The findings indicate that this group view the weirs as an integral part of the river and the river as an integral part of the Camden community

    Development Of VHF (240-270 MHz) Antennas For SoOp (Signal Of Opportunity) Receiver For 6u Cubesat Platforms

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    The main goal of this research is to design, fabricate, and test deployable VHF antennas for 6U Cubesat platforms to enable validation of root zone soil moisture (RZSM) estimation algorithms for signal of opportunity (SoOp) remote sensing over the 240-270 MHz frequency band. The proposed work provides a strong foundation for establishing a technology development path for maturing a truly global direct surface soil moisture (SM) and RZSM measurement system (Figure 1) over a variety of land covers with limited density restrictions. In SoOp methodology, signals transmitted by already existing transmitters (known as transmitters of opportunity, in this case the Military Satellite Communication (MilSatCom) System's UHF Follow-On program) are utilized to measure properties of reflecting targets by recording reflected signals using a simple passive microwave receiver
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