971 research outputs found

    Impact of endometritis on post-partum ovarian cyclicity in dairy cows

    Get PDF
    Endometritis in dairy cows is a major global issue and has been associated with a decrease in reproductive performance. The aim of this study was to quantify the effect of endometritis (as defined by the presence of any abnormal vaginal discharge after 21 days post-partum) on post-partum ovarian cyclicity in dairy cows. Milk progesterone analysis was used to monitor reproductive cyclicity in 170 dairy cows across three different commercial herds. Associations between the occurrence of endometritis and the incidence risk of a variety of atypical cycle profiles during the calving to conception period were investigated to establish the importance of endometritis on post-partum ovarian activity.Endometritis increased the incidence odds of atypical ovarian profiles (P [less than] 0.05) with prolonged luteal activity being the most affected (P [less than] 0.05), but also showed prolonged time (3 days) to onset of luteal activity after parturition (P [less than] 0.05). Using milk progesterone analysis, we found a relatively low incidence odds for reproductive cycle problems in healthy cows during the calving to conception period. However, the incidence odds of cycle problems, in particular prolonged luteal activity, were high in cows that had experienced endometritis, which would have significantly impaired reproductive function

    Milk progesterone on day 5 following insemination in the dairy cow: associated metabolic variables and reproductive consequences

    Get PDF
    Despite the importance of progesterone on the fertility of lactating dairy cows, the factors that affect post ovulatory progesterone concentration are still unclear. Thus, the aim of the present study was to identify factors associated with the post ovulatory progesterone rise following 1st insemination in lactating dairy cows. Data collected across a number of complimentary studies were compiled to produce a single database of 168 lactating Holstein Friesian dairy cows maintained under commercial conditions. In all animals a number of variables were measured during the insemination period and related to milk progesterone measured on day 5 following 1st artificial insemination (AI). Overall, 44% of cows conceived to 1st AI and while mean day 5 progesterone was not significantly higher in these cows, there was a significant quadratic relationship between milk progesterone concentration and conception rate. While a number of variables showed some association with progesterone concentration, the only variable showing a strong and repeatable relationship was plasma leptin concentration. We conclude that adequate but not excessive progesterone levels on day 5 bring about a better fertility, and plasma leptin concentration may be a much better indicator of metabolic status in lactating dairy cows.Keywords: Conception rate, dairy cow, leptin, metabolic variables, milk progesteron

    Kaluza-Klein Holography

    Full text link
    We construct a holographic map between asymptotically AdS_5 x S^5 solutions of 10d supergravity and vacuum expectation values of gauge invariant operators of the dual QFT. The ingredients that enter in the construction are (i) gauge invariant variables so that the KK reduction is independent of any choice of gauge fixing; (ii) the non-linear KK reduction map from 10 to 5 dimensions (constructed perturbatively in the number of fields); (iii) application of holographic renormalization. A non-trivial role in the last step is played by extremal couplings. This map allows one to reliably compute vevs of operators dual to any KK fields. As an application we consider a Coulomb branch solution and compute the first two non-trivial vevs, involving operators of dimension 2 and 4, and reproduce the field theory result, in agreement with non-renormalization theorems. This constitutes the first quantitative test of the gravity/gauge theory duality away from the conformal point involving a vev of an operator dual to a KK field (which is not one of the gauged supergravity fields).Comment: 47 pages, v2: minor improvements, version to appear in JHE

    Negative 4-Probe Conductances of Mesoscopic Superconducting Wires

    Full text link
    We analyze the longitudinal 4-probe conductance of mesoscopic normal and superconducting wires and predict that in the superconducting case, large negative values can arise for both the weakly disordered and localized regimes. This contrasts sharply with the behaviour of the longitudinal 4-probe conductance of normal wires, which in the localized limit is always exponentially small and positive.Comment: Latex, 3 figures available on request to [email protected] (Simon Robinson

    Real-world evidence use in assessments of cancer drugs by NICE

    Get PDF
    Objective To establish how real-world evidence (RWE) has been used to inform single technology appraisals (STAs) of cancer drugs conducted by the National Institute for Health and Care Excellence (NICE). Methods STAs published by NICE from April 2011 to October 2018 that evaluated cancer treatments were reviewed. Information regarding the use of RWE to directly inform the company-submitted cost-effectiveness analysis was extracted and categorized by topic. Summary statistics were used to describe emergent themes, and a narrative summary was provided for key case studies. Results Materials for a total of 113 relevant STAs were identified and analyzed, of which nearly all (96 percent) included some form of RWE within the company-submitted cost-effectiveness analysis. The most common categories of RWE use concerned the health-related quality of life of patients (71 percent), costs (46 percent), and medical resource utilization (40 percent). While sources of RWE were routinely criticized as part of the appraisal process, we identified only two cases where the use of RWE was overtly rejected; hence, in the majority of cases, RWE was accepted in cancer drug submissions to NICE. Discussion RWE has been used extensively in cancer submissions to NICE. Key criticisms of RWE in submissions to NICE are seldom regarding the use of RWE in general; instead, these are typically concerned with specific data sources and the applicability of these to the decision problem. Within an appropriate context, RWE constitutes an extremely valuable source of information to inform decision making; yet the development of best practice guidelines may improve current reporting standards

    Political brand image: an investigation into the operationalisation of the external orientation of David Cameron’s Conservative brand

    Get PDF
    This paper seeks to address the limited understanding of how to operationalise the external brand image of a political brand. More specifically, this research critically assesses the transfer potential of the six variables of brand image by Bosch, Venter, Han and Boshoff to deconstruct the UK Conservative Party brand from the perspective of young people aged 18–24 years during the 2010 UK General Election campaign. This research demonstrates the applicability of the six variables otherwise known as the ‘brand image framework’ to the political environment. However, the application of the brand image framework in its original conceptualisation proved problematic. Many of the brand image variables were clarified, rearticulated and simplified to address the political context. This refined conceptualisation provided an in-depth understanding of how to investigate the political brand image of David Cameron’s Conservative Party. This study addresses the paucity of research that operationalises external brand image and provides practitioners and academics within and beyond the context of political branding a mechanism to understand the external orientation of brands. This research may also be used by political and non-political brands as a basis to explore external brand image and compare its consistency with internal brand identity

    Radio Bursts Associated with Flare and Ejecta in the 13 July 2004 Event

    Full text link
    We investigate coronal transients associated with a GOES M6.7 class flare and a coronal mass ejection (CME) on 13 July 2004. During the rising phase of the flare, a filament eruption, loop expansion, a Moreton wave, and an ejecta were observed. An EIT wave was detected later on. The main features in the radio dynamic spectrum were a frequency-drifting continuum and two type II bursts. Our analysis shows that if the first type II burst was formed in the low corona, the burst heights and speed are close to the projected distances and speed of the Moreton wave (a chromospheric shock wave signature). The frequency-drifting radio continuum, starting above 1 GHz, was formed almost two minutes prior to any shock features becoming visible, and a fast-expanding piston (visible as the continuum) could have launched another shock wave. A possible scenario is that a flare blast overtook the earlier transient, and ignited the first type II burst. The second type II burst may have been formed by the same shock, but only if the shock was propagating at a constant speed. This interpretation also requires that the shock-producing regions were located at different parts of the propagating structure, or that the shock was passing through regions with highly different atmospheric densities. This complex event, with a multitude of radio features and transients at other wavelengths, presents evidence for both blast-wave-related and CME-related radio emissions.Comment: 14 pages, 6 figures; Solar Physics Topical Issue, in pres
    corecore