127 research outputs found

    Comparison of modelling techniques for milk-production forecasting

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    peer-reviewedThe objective of this study was to assess the suitability of 3 different modeling techniques for the prediction of total daily herd milk yield from a herd of 140 lactating pasture-based dairy cows over varying forecast horizons. A nonlinear auto-regressive model with exogenous input, a static artificial neural network, and a multiple linear regression model were developed using 3 yr of historical milk-production data. The models predicted the total daily herd milk yield over a full season using a 305-d forecast horizon and 50-, 30-, and 10-d moving piecewise horizons to test the accuracy of the models over long- and short-term periods. All 3 models predicted the daily production levels for a full lactation of 305 d with a percentage root mean square error (RMSE) of ≤12.03%. However, the nonlinear auto-regressive model with exogenous input was capable of increasing its prediction accuracy as the horizon was shortened from 305 to 50, 30, and 10 d [RMSE (%) = 8.59, 8.1, 6.77, 5.84], whereas the static artificial neural network [RMSE (%) = 12.03, 12.15, 11.74, 10.7] and the multiple linear regression model [RMSE (%) = 10.62, 10.68, 10.62, 10.54] were not able to reduce their forecast error over the same horizons to the same extent. For this particular application the nonlinear auto-regressive model with exogenous input can be presented as a more accurate alternative to conventional regression modeling techniques, especially for short-term milk-yield predictions

    We need to talk about values: a proposed framework for the articulation of normative reasoning in health technology assessment

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    It is acknowledged that health technology assessment (HTA) is an inherently value-based activity that makes use of normative reasoning alongside empirical evidence. But the language used to conceptualise and articulate HTA's normative aspects is demonstrably unnuanced, imprecise, and inconsistently employed, undermining transparency and preventing proper scrutiny of the rationales on which decisions are based. This paper – developed through a cross-disciplinary collaboration of 24 researchers with expertise in healthcare priority-setting – seeks to address this problem by offering a clear definition of key terms and distinguishing between the types of normative commitment invoked during HTA, thus providing a novel conceptual framework for the articulation of reasoning. Through application to a hypothetical case, it is illustrated how this framework can operate as a practical tool through which HTA practitioners and policymakers can enhance the transparency and coherence of their decision-making, while enabling others to hold them more easily to account. The framework is offered as a starting point for further discussion amongst those with a desire to enhance the legitimacy and fairness of HTA by facilitating practical public reasoning, in which decisions are made on behalf of the public, in public view, through a chain of reasoning that withstands ethical scrutiny.Wellcome Trust Society and Ethics Doctoral StudentshipClinical Center Department of Bioethics - the Intramural Program of the US National Institutes of HealthArnold VenturesTo check citing and date details in 6

    Adherence to Discounting Guidelines: Evidence from Over 2000 Published Cost-Effectiveness Analyses

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    Previous studies have shown that not all cost-effectiveness analyses (CEAs) adhere to recommended guidelines on intertemporal discounting. This analysis investigates adherence in a sample of over 2000 CEAs from seven countries. Guideline discount rates were retrieved for Australia, Belgium, Canada, Ireland, The Netherlands, New Zealand and the UK. Data on the rates applied in published CEAs were retrieved from the Tufts CEA Registry from the sample countries within the periods covered by the discounting guidelines. The relationship between adherence and candidate explanatory factors were assessed using logistic regression. The analysis appraised 2270 CEAs. The overall rate of adherence to discounting recommendations was 79%. Country-specific adherence ranged from 28% in New Zealand to 87% in Belgium and the UK. Adherence in Australia and Canada was 73% and 66%, respectively. Adherence is statistically significantly higher in more recent studies, countries currently applying differential discounting and manufacturer-sponsored studies. Relative to the reference case of Australia, adherence is statistically significantly higher in the UK and lower in Canada and New Zealand. There is notable variation in the rates of adherence to discounting recommendations between countries and over time. Incomplete adherence raises concerns regarding the comparability of evidence between studies. In turn, this raises concerns regarding equity of access to scarce healthcare resources. Journal editors should ensure that adherence to discounting recommendations is assessed as part of the peer review process.Access provided by IREL Consortium c/o Maynooth University The Library Maynooth Universit

    Intermanifold similarities in partial photoionization cross sections of helium

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    Using the eigenchannel R-matrix method we calculate partial photoionization cross sections from the ground state of the helium atom for incident photon energies up to the N=9 manifold. The wide energy range covered by our calculations permits a thorough investigation of general patterns in the cross sections which were first discussed by Menzel and co-workers [Phys. Rev. A {\bf 54}, 2080 (1996)]. The existence of these patterns can easily be understood in terms of propensity rules for autoionization. As the photon energy is increased the regular patterns are locally interrupted by perturber states until they fade out indicating the progressive break-down of the propensity rules and the underlying approximate quantum numbers. We demonstrate that the destructive influence of isolated perturbers can be compensated with an energy-dependent quantum defect.Comment: 10 pages, 10 figures, replacement with some typos correcte

    Mending a Broken Heart: Treatment of Stress-Induced Heart Failure after Solid Organ Transplantation

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    Stress-induced heart failure, also known as Broken Heart Syndrome or Takotsubo Syndrome, is a phenomenon characterized as rare but well described in the literature, with increasing incidence. While more commonly associated with postmenopausal women with psychiatric disorders, this entity is found in the postoperative patient. The nonischemic cardiogenic shock manifests as biventricular failure with significant decreases in ejection fraction and cardiac function. In a review of over 3000 kidney and liver transplantations over the course of 17 years within two transplant centers, we describe a series of 7 patients with Takotsubo Syndrome after solid organ transplantation. Furthermore, we describe a novel approach of successfully treating the transient, though potentially fatal, cardiogenic shock with a percutaneous ventricular assistance device in two liver transplant patients, while treating one kidney transplant patient medically and the remaining four liver transplant patients with an intra-aortic balloon pump. We describe our experience with Takotsubo’s Syndrome and compare the three modalities of treatment and cardiac augmentation. Our series is novel in introducing the percutaneous ventricular assist device as a more minimally invasive intervention in treating nonischemic heart failure in the solid organ transplant patient, while serving as a comprehensive overview of treatment modalities for stress-induced heart failure

    Deprescribing tool for STOPPFall (screening tool of older persons prescriptions in older adults with high fall risk) items

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    Background: Health care professionals are often reluctant to deprescribe fall-risk-increasing drugs (FRIDs). Lack of knowledge and skills form a significant barrier. To support clinicians in the management of FRIDs and to facilitate the deprescribing process, a deprescribing tool was developed by a European expert group for STOPPFall (Screening Tool of Older Persons Prescriptions in older adults with high fall risk) items. Methods: STOPPFall was created using an expert Delphi consensus process in 2019 and in 2020, 24 panellists from EuGMS SIG on Pharmacology and Task and Finish on FRIDs completed deprescribing tool questionnaire. To develop the questionnaire, a Medline literature search was performed. The panellists were asked to indicate for every medication class a possible need for stepwise withdrawal and strategy for withdrawal. They were asked in which situations withdrawal should be performed. Furthermore, panellists were requested to indicate those symptoms patients should be monitored for after deprescribing and a possible need for follow-ups. Results: Practical deprescribing guidance was developed for STOPPFall medication classes. For each medication class, a decision tree algorithm was developed including steps from medication review to symptom monitoring after medication withdrawal. Conclusion: STOPPFall was combined with a practical deprescribing tool designed to optimize medication review. This practical guide can help overcome current reluctance towards deprescribing in clinical practice by providing an up-to-date and straightforward source of expert knowledge

    Innovative remote plasma source for atomic layer deposition for GaN devices

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    High-quality dielectric films could enable GaN normally off high-electron-mobility transistors (HEMTs). Plasma atomic layer deposition (ALD) is known to allow for controlled high-quality thin-film deposition, and in order to not exceed energy and flux levels leading to device damage, the plasma used should preferably be remote for many applications. This article outlines ion energy flux distribution functions and flux levels for a new remote plasma ALD system, Oxford Instruments Atomfab™, which includes an innovative, RF-driven, remote plasma source. The source design is optimized for ALD for GaN HEMTs for substrates up to 200 mm in diameter and allows for Al2O3 ALD cycles of less than 1 s. Modest ion energies of <50 eV and very low ion flux levels of <1013 cm−2 s−1 were found at low-damage conditions. The ion flux can be increased to the high 1014 cm−2 s−1 range if desired for other applications. Using low-damage conditions, fast ALD saturation behavior and good uniformity were demonstrated for Al2O3. For films of 20 nm thickness, a breakdown voltage value of 8.9 MV/cm was obtained and the Al2O3 films were demonstrated to be suitable for GaN HEMT devices where the combination with plasma pretreatment and postdeposition anneals resulted in the best device parameters

    The UK Pharmacy Care Plan service: Description, recruitment and initial views on a new community pharmacy intervention

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    Introduction: The UK government advocates person-centred healthcare which is ideal for supporting patients to make appropriate lifestyle choices and to address non-adherence. The Community Pharmacy Future group, a collaboration between community pharmacy companies and independents in the UK, introduced a person-centred service for patients with multiple long-term conditions in 50 pharmacies in Northern England. Objective: Describe the initial findings from the set up and delivery of a novel community pharmacy-based person-centred service. Method: Patients over fifty years of age prescribed more than one medicine including at least one for cardiovascular disease or diabetes were enrolled. Medication review and person-centred consultation resulted in agreed health goals and steps towards achieving them. Data were collated and analysed to determine appropriateness of patient recruitment process and quality of outcome data collection. A focus group of seven pharmacists was used to ascertain initial views on the service. Results: Within 3 months of service initiation, 683 patients had baseline clinical data recorded, of which 86.9% were overweight or obese, 53.7% had hypertension and 80.8% had high cardiovascular risk. 544 (77.2%) patients set at least one goal during the first consultation with 120 (22.1%) setting multiple goals. A majority of patients identified their goals as improvement in condition, activity or quality of life. Pharmacists could see the potential patient benefit and the extended role opportunities the service provided. Allowing patients to set their own goals occasionally identified gaps to be addressed in pharmacist knowledge. Conclusion: Pharmacists successfully recruited a large number of patients who were appropriate for such a service. Patients were willing to identify goals with the pharmacist, the majority of which, if met, may result in improvements in quality of life. While challenges in delivery were acknowledged, allowing patients to identify their own personalised goals was seen as a positive approach to providing patient services
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