1,076 research outputs found

    Histopathological Characterization of the Lesions of Contagious Ovine Digital Dermatitis and Immunolabelling of Treponema-like Organisms

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    SummaryContagious ovine digital dermatitis (CODD) is a cause of severe lameness in sheep and the three Treponema phylogroups Treponema medium/Treponema vincentii-like, Treponema phagedenis-like and Treponema pedis have been associated with clinical disease. The aims of this study were: (1) to describe the histopathological changes associated with each previously established grade of clinical lesion, and (2) to investigate immunohistochemically the association of the Treponema-like organisms with the observed histopathological changes. Early lesions were characterized by lymphoplasmacytic infiltration of the distal digital skin, with suppurative coronitis and intracorneal pustules. In more advanced stages of the disease there was complete separation of the dorsal wall of the hoof with a necrotizing and fibrinosuppurative exudate and dermatitis. The later lesions were mostly resolved, but with milder suppurative changes remaining within the cornified layer and periosteal reaction of the dorsal aspect of the distal phalanx. Large numbers of Treponema-like organisms were identified within early grade lesions (as well as later, more advanced grade lesions) and were specifically associated with the observed histopathological changes. The results of this study provide some evidence in support of the hypothesis that the three CODD-associated Treponema phylogroups are involved in the aetiopathogenesis of this disease

    Structure of the ovaries of the Nimba otter shrew, Micropotamogale lamottei, and the Madagascar hedgehog tenrec, Echinops telfairi

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    The otter shrews are members of the subfamily Potamogalinae within the family Tenrecidae. No description of the ovaries of any member of this subfamily has been published previously. The lesser hedgehog tenrec, Echinops telfairi, is a member of the subfamily Tenrecinae of the same family and, although its ovaries have not been described, other members of this subfamily have been shown to have ovaries with non-antral follicles. Examination of these two species illustrated that non-antral follicles were characteristic of the ovaries of both species, as was clefting and lobulation of the ovaries. Juvenile otter shrews range from those with only small follicles in the cortex to those with 300- to 400-mu m follicles similar to those seen in non-pregnant and pregnant adults. As in other species, most of the growth of the oocyte occurred when follicles had one to two layers of granulosa cells. When larger follicles became atretic in the Nimba otter shrew, hypertrophy of the theca interna produced nodules of glandular interstitial tissue. In the tenrec, the hypertrophying theca interna cells in most large follicles appeared to undergo degeneration. Both species had some follicular fluid in the intercellular spaces between the more peripheral granulosa cells. It is suggested that this fluid could aid in separation of the cumulus from the remaining granulosa at ovulation. The protruding follicles in lobules and absence of a tunica albuginea might also facilitate ovulation of non-antral follicles. Ovaries with a thin-absent tunica albuginea and follicles with small-absent antra are widespread within both the Eulipotyphla and in the Afrosoricida, suggesting that such features may represent a primitive condition in ovarian development. Lobulated and deeply crypted ovaries are found in both groups but are not as common in the Eulipotyphla making inclusion of this feature as primitive more speculative. Copyright (C) 2005 S. Karger AG, Basel

    Anisotropic Superexchange for nearest and next nearest coppers in chain, ladder and lamellar cuprates

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    We present a detailed calculation of the magnetic couplings between nearest-neighbor and next-nearest-neighbor coppers in the edge-sharing geometry, ubiquitous in many cuprates. In this geometry, the interaction between nearest neighbor coppers is mediated via two oxygens, and the Cu-O-Cu angle is close to 90 degrees. The derivation is based on a perturbation expansion of a general Hubbard Hamiltonian, and produces numerical estimates for the various magnetic energies. In particular we find the dependence of the anisotropy energies on the angular deviation away from the 90 degrees geometry of the Cu-O-Cu bonds. Our results are required for the correct analysis of the magnetic structure of various chain, ladder and lamellar cuprates.Comment: 13 pages, Latex, 7 figure

    Global Warming: Forecasts by Scientists versus Scientific Forecasts

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    In 2007, the Intergovernmental Panel on Climate Change’s Working Group One, a panel of experts established by the World Meteorological Organization and the United Nations Environment Programme, issued its Fourth Assessment Report. The Report included predictions of dramatic increases in average world temperatures over the next 92 years and serious harm resulting from the predicted temperature increases. Using forecasting principles as our guide we asked: Are these forecasts a good basis for developing public policy? Our answer is “no”. To provide forecasts of climate change that are useful for policy-making, one would need to forecast (1) global temperature, (2) the effects of any temperature changes, and (3) the effects of feasible alternative policies. Proper forecasts of all three are necessary for rational policy making. The IPCC WG1 Report was regarded as providing the most credible long-term forecasts of global average temperatures by 31 of the 51 scientists and others involved in forecasting climate change who responded to our survey. We found no references in the 1056-page Report to the primary sources of information on forecasting methods despite the fact these are conveniently available in books, articles, and websites. We audited the forecasting processes described in Chapter 8 of the IPCC’s WG1 Report to assess the extent to which they complied with forecasting principles. We found enough information to make judgments on 89 out of a total of 140 forecasting principles. The forecasting procedures that were described violated 72 principles. Many of the violations were, by themselves, critical. The forecasts in the Report were not the outcome of scientific procedures. In effect, they were the opinions of scientists transformed by mathematics and obscured by complex writing. Research on forecasting has shown that experts’ predictions are not useful in situations involving uncertainly and complexity. We have been unable to identify any scientific forecasts of global warming. Claims that the Earth will get warmer have no more credence than saying that it will get colder

    Dynamic generation of maximally entangled photon multiplets by adiabatic passage

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    The adiabatic passage scheme for quantum state synthesis, in which atomic Zeeman coherences are mapped to photon states in an optical cavity, is extended to the general case of two degenerate cavity modes with orthogonal polarization. Analytical calculations of the dressed-state structure and Monte Carlo wave-function simulations of the system dynamics show that, for a suitably chosen cavity detuning, it is possible to generate states of photon multiplets that are maximally entangled in polarization. These states display nonclassical correlations of the type described by Greenberger, Horne, and Zeilinger (GHZ). An experimental scheme to realize a GHZ measurement using coincidence detection of the photons escaping from the cavity is proposed. The correlations are found to originate in the dynamics of the adiabatic passage and persist even if cavity decay and GHZ state synthesis compete on the same time scale. Beyond entangled field states, it is also possible to generate entanglement between photons and the atom by using a different atomic transition and initial Zeeman state.Comment: 22 pages (RevTeX), including 23 postscript figures. To be published in Physical Review

    Northern European trees show a progressively diminishing response to increasing atmospheric carbon dioxide concentrations

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    In order to predict accurately how elevated atmospheric CO2 concentrations will affect the global carbon cycle, it is necessary to know how trees respond to increasing CO2 concentrations. In this paper we examine the response over the period AD 1895 – 1994 of three tree species growing across northern Europe to increases in atmospheric CO2 concentrations using parameters derived from stable carbon isotope ratios of trunk cellulose. Using the isotope data we calculate values of intrinsic water-use efficiency (IWUE) and intercellular CO2 concentrations in the leaf (ci). Our results show that trees have responded to higher levels of atmospheric CO2 by increasing IWUE whilst generally maintaining constant ci values. However, the IWUE of most of the trees in this study has not continued to rise in line with increasing atmospheric CO2. This behaviour has implications for estimations of future terrestrial carbon storage

    Personal goals, group performance and ‘social’ networks: participants’ negotiation of virtual and embodied relationships in the ‘Workplace Challenge’ physical activity programme

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    County Sports Partnerships (CSPs) epitomise the growing reliance upon building networks and partnerships sports delivery. This study investigated how social networks were created and contested in a CSP-led programme entitled the ‘Workplace Challenge’ (WPC). The WPC used a web-platform to encourage workplace-based teams to engage in physical activity by self-recording their activity over an eight-week period. Points were awarded for activity completed and a peer-challenge facility was promoted via online league tables, prizes and the opportunity to ‘challenge’ other users. Semi-structured interviews were conducted with a total of seventeen participants recruited from one public and one private sector workplace and from a sample of participants registered as individuals. Two programme planners employed by the CSP also took part. A figurational framework was utilised to investigate participants’ negotiation of networks of embodied and virtual relationships within the programme. Findings suggest the messages promoted in the WPC were disseminated and transformed according to the organizational structure of these networks. Embodied social relationships within workplaces reinforced peer support in professional I-we identities, whereas virtual networks sometimes highlighted participants’ isolation. Moreover, emphasis upon competition within and between teams caused some to question their performance. Often, competition motivated engagement. For less active participants, constant comparison could prove discouraging, particularly if participants felt they had let their colleagues down. Planners of similar programmes must be cognizant of the uneven manner of programme dissemination. Contextual differences at the point of delivery including existing organizational structures and power hierarchies have an impact upon participants’ perceptions of a programme

    Ambulatory cancer care electronic symptom self-reporting (ACCESS) for surgical patients: A randomised controlled trial protocol

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    Introduction An increasing proportion of cancer surgeries are ambulatory procedures requiring a stay of 1 day or less in the hospital. Providing patients and their caregivers with ongoing, real-time support after discharge aids delivery of high-quality postoperative care in this new healthcare environment. Despite abundant evidence that patient self-reporting of symptoms improves quality of care, the most effective way to monitor and manage this self-reported information is not known. Methods and analysis This is a two-armed randomised, controlled trial evaluating two approaches to the management of patient-reported data: (1) team monitoring, symptom monitoring by the clinical team, with nursing outreach if symptoms exceed normal limits, and (2) enhanced feedback, real-time feedback to patients about expected symptom severity, with patient-activated care as needed. Patients with breast, gynaecologic, urologic, and head and neck cancer undergoing ambulatory cancer surgery (n=2750) complete an electronic survey for up to 30 days after surgery that includes items from a validated instrument developed by the National Cancer Institute, the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE). Information provided to patients in the Enhanced Feedback group is procedure-specific and based on updated PRO-CTCAE data from previous patients. Qualitative interviews are also performed. The primary study outcomes assess unplanned emergency department visits and symptom-triggered interventions (eg, nursing calls and pain management referrals) within 30 days, and secondary outcomes assess the patient and caregiver experience (ie, patient engagement, patient anxiety and caregiver burden). Ethics and dissemination This study is approved by the Institutional Review Board at Memorial Sloan Kettering Cancer Center. The relationships between the study team and stakeholders will be leveraged to disseminate study findings. Findings will be relevant in designing future coordinated care models targeting improved healthcare quality and patient experience. Trial registration number NCT03178045

    The First VERITAS Telescope

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    The first atmospheric Cherenkov telescope of VERITAS (the Very Energetic Radiation Imaging Telescope Array System) has been in operation since February 2005. We present here a technical description of the instrument and a summary of its performance. The calibration methods are described, along with the results of Monte Carlo simulations of the telescope and comparisons between real and simulated data. The analysis of TeV γ\gamma-ray observations of the Crab Nebula, including the reconstructed energy spectrum, is shown to give results consistent with earlier measurements. The telescope is operating as expected and has met or exceeded all design specifications.Comment: Accepted by Astroparticle Physic

    Second generation anticoagulant rodenticide residues in red kites 2022

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    •Second-generation anticoagulant rodenticides (SGARs) can be toxic to all mammals and birds if consumed. Various studies have shown that, in Britain, there is widespread exposure to SGARs in a diverse range of predatory mammals and birds, including red kites (Milvus milvus) which scavenge dead rats, a target species for rodent control. The Wildlife Incident Investigation Scheme (WIIS) and the Predatory Bird Monitoring Scheme (PBMS) have shown that some mortalities result from this secondary exposure. •In the present study, we analysed liver SGAR residues in 14 red kites that had been found dead in Britain in 2022. One bird collected in 2021 was also chemically analysed and added to the time trend analysis of this report. The carcasses were submitted to and necropsied by the Disease Risk Analysis and Health Surveillance (DRAHS) programme, the PBMS, and the WIIS for England & Wales. In 2022, there were no birds received from Scotland (i.e., no bird from the WIIS for Scotland and the Raptor Health Scotland study). All these organisations are partners in the WILDCOMS (Wildlife Disease & Contaminant Monitoring & Surveillance Network) network that promotes collaboration among surveillance schemes that monitor disease and contaminants in vertebrate wildlife in the UK. •The UK Rodenticide Stewardship Regime (hereafter referred to as the stewardship scheme) began to come into force in mid-2016 as re-registration of products for use in the UK was approved by the HSE; full implementation of the scheme was in early 2018. The key aim of this stewardship initiative is to support competence among all users of professional SGAR products. A potential benefit of this may be the reduced exposure of non-target wildlife to anticoagulant rodenticides. However, the number and density of SGAR-contaminated rats may remain unchanged although diligent searching, removal, and safe disposal of poisoned rats, as promoted by the stewardship regime, might be expected to reduce the availability of poisoned dead rats to red kites (and other scavengers) and thereby reduce the proportion of birds that are exposed and/or the magnitude of exposure. Concomitant with the stewardship scheme was a relaxation of the indoor-use-only-restriction applied to brodifacoum, flocoumafen, and difethialone, the three most acutely toxic SGARs to use indoor and outdoor around buildings. Any consequent increase in outdoor use of these three SGARs could increase the risk of secondary exposure in red kites. We therefore compared the data in the current report with that collected in 2015 and 2016 to determine if there was any evidence of a change in pattern or magnitude of exposure in red kites that might be connected to stewardship and/or change in usage restriction. •All of the 14 red kites from England & Wales in 2022 had detectable liver residues of at least one type of SGAR. Brodifacoum, difenacoum, and bromadiolone were each detected in 13, 13 and 6 red kites, respectively. Difethialone was found in two individuals while flocoumafen was detected in no bird. •The proportion of analysed red kites exposed to SGARs in 2015 (91%), 2016 (90%), 2017 (96%), 2018 (100%), 2019 (91%), 2020 (88%), 2021 (98%), and 2022 (100%) was similar at circa 90% or more; the higher percentages in 2017 and 2018 were principally due to a greater proportion of birds from Scotland containing residues than observed in other years. However, all red kites from England and Wales were exposed to SGARs in 2022. Difenacoum, brodifacoum, and bromadiolone were the most prevalent compounds (detected in 87%, 87%, and 75% of red kites across the eight years for each compound, respectively). On average, there were detectable residues of two different SGARs in each red kite liver likely demonstrating multiple exposures. •Sum liver SGAR concentrations in birds from 2022 ranged between 30 and 988 ng/g wet weight (arithmetic mean: 380 ng/g wet weight, median 257.9 ng/g wet weight). Necropsy examinations indicated that two red kites showed signs of being poisoned by SGARs (i.e., showing internal haemorrhaging that is not associated with detectable trauma and also having detectable liver SGAR concentrations). These samples accounted for 17% of the red kites of the year excluding uncertain poisoning cases. These two birds had sum SGAR liver concentrations of 544.2 and 661.6 ng/g wet weight. SGARs were considered a contributory cause of death resulting from unspecified use in these cases. SGARs were a contributory cause of death in 16% of the red kite cases examined across all eight years. Over the period 2015 to 2022, a reduction has been observed in the percentage of red kites examined that were diagnosed as birds in which SGARs were implicated as a contributory cause of death. However, given that the WIIS scheme specifically examines suspected poisoning incidents, it is likely that poisoned birds are over represented in this sample compared to the population as a whole in all eight years. Due to these reasons, caution should be used when interpreting evident changes in poisoned bird rates due to the opportunistic sampling methods used in this study that may lead to over reporting of poisoned birds. Those rates being subject to variations in relative contribution of the WIIS and PBMS to each year’s sample. It should be noted that sub-lethal poisoning due to SGAR exposure is not considered in this report. •There were statistically significant differences between years in median summed SGAR residues for non-poisoned birds and in all red kites combined with poisoned and non-poisoned birds. The magnitude of accumulated summed SGAR residues, particularly sum of brodifacoum, flocoumafen, and difethialone concentrations, was significantly higher in 2022 than in 2019. Given low occurrence and low concentrations of flocoumafen and difethialone residues, it is demonstrated that the magnitude of brodifacoum residues has increased over recent years. •Data on presence/absence of detectable brodifacoum, flocoumafen or difethialone residues were compared for 2015/2016 and 2017/18/19/20/21/22. The proportion of red kites with detectable residues of these three SGARs was not significantly different between 2015/2016 (82%) and 2017/18/19/20/21/22 (89%). Similarly, there was no significant difference in the proportion of red kites with detectable liver difenacoum or bromadiolone residues (90% in 2015/2016 vs. 94% in 2017/18/19/20/21/22). Since the implementation of the stewardship regime, no difference in exposure pattern relating to active ingredients has been detected with the exception of an increase in the concentrations of brodifacoum. •Spatial analysis by county/region indicated that across the monitoring period highest exposure to SGARs in red kites appeared to be around the Berkshire/Hampshire and, to a lesser extent, North Yorkshire. •Our findings do not indicate that there has been a consistent broad scale change in exposure in red kites to SGARs following implementation of stewardship in terms of either the proportion of the sample exposed or the magnitude of sum SGARs residues detected. However, there is evidence that the proportion of red kites in which SGARs were implicated as a contributory mortality factor has decreased in more recent years. Alternative approaches to monitoring SGARs in red kites could be considered that analyse a random but representative sample, and as part of such a programme there may also be value in monitoring SGARs in the blood of tracked individuals. Brodifacoum exposure has increased in recent years, but whether this change in exposure has been caused by the relaxation of usage restrictions on brodifacoum, difethialone and flocoumafen is still a question to be addressed
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