198 research outputs found

    1/mb1/m_b Corrections in the ACCMM Model for Inclusive Semileptonic B Decay

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    We re-examine the model of Altarelli, Cabibbo, Corb\`{o}, Maiani and Martinelli for inclusive semileptonic B decay, in the light of recent calculations in heavy quark effective theory. The model can be shown to have no~1/mb1/m_b corrections, with a suitable definition of the b quark mass~mbm_b. However, we find that the structure of the 1/mb21/m_b^2~terms is incompatible with the predictions of heavy quark effective theory. The numerical significance of this discrepancy is discussed.Comment: 10 pages (uses revtex), UCLA/93/TEP/4

    Developing life cycle inventory for life cycle assessment of Australian cotton

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    Life Cycle Assessment (LCA) is an internationally recognised approach for evaluating the environmental impacts of products and services. In this paper, the potential issues in the development of a consistent and comprehensive life cycle inventory (LCI) data are illustrated in the context of Australian cotton industry. These include diversity and variable nature of farming practices, and the inherent complexities such as the inter-linkages between co-products. For the implementation of LCI, the choices of functional unit and system boundary, definition of regional sub-sectors, methods of energy assessments, and rules of allocations of inputs and emissions are discussed. It is shown that for cotton production, the contribution of on-farm indirect 'chemical' inputs is particularly important, accounting for up to 50–80% of the total energy input in the life cycle. The need for quantified trade off analysis between alternative systems in the LCA context is also emphasized

    Observing b→s μ+μ−b \rightarrow s \, \mu^+ \mu^- Decays at Hadron Colliders

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    We examine the prospects for observing weak flavour-changing neutral current (FCNC) decays of \B\ mesons at hadron colliders, including effects of anomalous WWZWWZ~vertices. Since it is very difficult to measure the inclusive rate B \rightarrow X_s \, \lp \lm one should consider exclusive modes such as \BKsmumu\ and \BKmumu. Even though this requires one to compute hadronic matrix elements, we show that experimentally observable quantities (ratios of decay rates) are not strongly parametrisation dependent. Some possibilities for reducing the theoretical uncertainties from other experimental data are discussed.Comment: 17 pages, uses LaTeX, epsf and uufiles. UCLA/93/TEP/2

    Realising dignity in care home practice: an action research project

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    Background: More than 400,000 older people reside in over 18,000 care homes in England. A recent social care survey found up to 50% of older people in care homes felt their dignity was undermined. Upholding the dignity of older people in care homes has implications for residents’ experiences and the role of Registered Nurses. Aims and objectives: The study aimed to explore how best to translate the concept of dignity into care home practice, and how to support this translation process by enabling Registered Nurses to provide ethical leadership within the care home setting. Design: Action research with groups of staff (Registered Nurses and non-registered caregivers) and groups of residents and relatives in four care homes in the south of England to contribute to the development of the dignity toolkit. Methods: Action research groups were facilitated by 4 researchers (2 in each care home) to discuss dignity principles and experiences within care homes. These groups reviewed and developed a dignity toolkit over six cycles of activity (once a month for 6 months). The Registered Nurses were individually interviewed before and after the activity. Results: Hard copy and online versions of a dignity toolkit, with tailored versions for participating care homes, were developed. Registered Nurses and caregivers identified positive impact of making time for discussion about dignity-related issues. Registered Nurses identified ongoing opportunities for using their toolkit to support all staff. Conclusions: Nurses and caregivers expressed feelings of empowerment by the process of action research. The collaborative development of a dignity toolkit within each care home has the potential to enable ethical leadership by Registered Nurses that would support and sustain dignity in care homes. Implications for practice: Action research methods empower staff to maintain dignity for older people within the care home setting through the development of practically useful toolkits to support everyday care practice. Providing opportunities for caregivers to be involved in such initiatives may promote their dignity and sense of being valued. The potential of bottom-up collaborative approaches to promote dignity in care therefore requires further research

    Analysis of SARS-CoV-2 in Nasopharyngeal Samples from Patients with COVID-19 Illustrates Population Variation and Diverse Phenotypes, Placing the Growth Properties of Variants of Concern in Context with Other Lineages

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    New variants of SARS-CoV-2 are continuing to emerge and dominate the global sequence landscapes. Several variants have been labeled variants of concern (VOCs) because they may have a transmission advantage, increased risk of morbidity and/or mortality, or immune evasion upon a background of prior infection or vaccination. Placing the VOCs in context with the underlying variability of SARS-CoV-2 is essential in understanding virus evolution and selection pressures. Dominant genome sequences and the population genetics of SARS-CoV-2 in nasopharyngeal swabs from hospitalized patients were characterized. Nonsynonymous changes at a minor variant level were identified. These populations were generally preserved when isolates were amplified in cell culture. To place the Alpha, Beta, Delta, and Omicron VOCs in context, their growth was compared to clinical isolates of different lineages from earlier in the pandemic. The data indicated that the growth in cell culture of the Beta variant was more than that of the other variants in Vero E6 cells but not in hACE2-A549 cells. Looking at each time point, Beta grew more than the other VOCs in hACE2-A549 cells at 24 to 48 h postinfection. At 72 h postinfection there was no difference in the growth of any of the variants in either cell line. Overall, this work suggested that exploring the biology of SARS-CoV-2 is complicated by population dynamics and that these need to be considered with new variants. In the context of variation seen in other coronaviruses, the variants currently observed for SARS-CoV-2 are very similar in terms of their clinical spectrum of disease. IMPORTANCE SARS-CoV-2 is the causative agent of COVID-19. The virus has spread across the planet, causing a global pandemic. In common with other coronaviruses, SARS-CoV-2 genomes can become quite diverse as a consequence of replicating inside cells. This has given rise to multiple variants from the original virus that infected humans. These variants may have different properties and in the context of a widespread vaccination program may render vaccines less effective. Our research confirms the degree of genetic diversity of SARS-CoV-2 in patients. By comparing the growth of previous variants to the pattern seen with four variants of concern (VOCs) (Alpha, Beta, Delta, and Omicron), we show that, at least in cells, Beta variant growth exceeds that of Alpha, Delta, and Omicron VOCs at 24 to 48 h in both Vero E6 and hACE2-A549 cells, but by 72 h postinfection, the amount of virus is not different from that of the other VOCs

    Support for UNRWA's survival

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    The United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) provides life-saving humanitarian aid for 5·4 million Palestine refugees now entering their eighth decade of statelessness and conflict. About a third of Palestine refugees still live in 58 recognised camps. UNRWA operates 702 schools and 144 health centres, some of which are affected by the ongoing humanitarian disasters in Syria and the Gaza Strip. It has dramatically reduced the prevalence of infectious diseases, mortality, and illiteracy. Its social services include rebuilding infrastructure and homes that have been destroyed by conflict and providing cash assistance and micro-finance loans for Palestinians whose rights are curtailed and who are denied the right of return to their homeland

    The Efficacy of Emamectin Benzoate against Infestations of Lepeophtheirus salmonis on Farmed Atlantic Salmon (Salmo salar L) in Scotland, 2002–2006

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    Infestations of the parasitic copepod Lepeophtheirus salmonis, commonly referred to as sea lice, represent a major challenge to commercial salmon aquaculture. Dependence on a limited number of theraputants to control such infestations has led to concerns of reduced sensitivity in some sea lice populations. This study investigates trends in the efficacy of the in-feed treatment emamectin benzoate in Scotland, the active ingredient most widely used across all salmon producing regions. Study data were drawn from over 50 commercial Atlantic salmon farms on the west coast of Scotland between 2002 and 2006. An epi-informatics approach was adopted whereby available farm records, descriptive epidemiological summaries and statistical linear modelling methods were used to identify factors that significantly affect sea lice abundance following treatment with emamectin benzoate (SLICEH, Schering Plough Animal Health). The results show that although sea lice infestations are reduced following the application of emamectin benzoate, not all treatments are effective. Specifically there is evidence of variation across geographical regions and a reduction in efficacy over time. Reduced sensitivity and potential resistance to currently available medicines are constant threats to maintaining control of sea lice populations on Atlantic salmon farms. There is a need for on-going monitoring of emamectin benzoate treatment efficacy together with reasons for any apparent reduction in performance. In addition, strategic rotation of medicines should be encouraged and empirical evidence for the benefit of such strategies more fully evaluated

    Cyclic AMP Control Measured in Two Compartments in HEK293 Cells: Phosphodiesterase KM Is More Important than Phosphodiesterase Localization

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    The intracellular second messenger cyclic AMP (cAMP) is degraded by phosphodiesterases (PDE). The knowledge of individual families and subtypes of PDEs is considerable, but how the different PDEs collaborate in the cell to control a cAMP signal is still not fully understood. In order to investigate compartmentalized cAMP signaling, we have generated a membrane-targeted variant of the cAMP Bioluminiscence Resonance Energy Transfer (BRET) sensor CAMYEL and have compared intracellular cAMP measurements with it to measurements with the cytosolic BRET sensor CAMYEL in HEK293 cells. With these sensors we observed a slightly higher cAMP response to adenylyl cyclase activation at the plasma membrane compared to the cytosol, which is in accordance with earlier results from Fluorescence Resonance Energy Transfer (FRET) sensors. We have analyzed PDE activity in fractionated lysates from HEK293 cells using selective PDE inhibitors and have identified PDE3 and PDE10A as the major membrane-bound PDEs and PDE4 as the major cytosolic PDE. Inhibition of membrane-bound or cytosolic PDEs can potentiate the cAMP response to adenylyl cyclase activation, but we see no significant difference between the potentiation of the cAMP response at the plasma membrane and in cytosol when membrane-bound and cytosolic PDEs are inhibited. When different levels of stimulation were tested, we found that PDEs 3 and 10 are mainly responsible for cAMP degradation at low intracellular cAMP concentrations, whereas PDE4 is more important for control of cAMP at higher concentrations

    Sheep Updates 2007 - part 4

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    This session covers eight papers from different authors: GRAZING 1. The impact of high dietary salt and its implications for the management of livestock grazing saline land, Dean Thomas, Dominique Blache, Dean Revell, Hayley Norman, Phil Vercoe, Zoey Durmic, Serina Digby, Di Mayberry, Megan Chadwick, Martin Sillence and David Masters, CRC for Plant-based Management of Dryland Salinity, Faculty of Natural & Agricultural Sciences, The University of Western Australia, WA. 2. Sustainable Grazing on Saline Lands - outcomes from the WA1 research project, H.C. Norman1,2, D.G. Masters1,2, R. Silberstein1,2, F. Byrne2,3, P.G.H. Nichols2,4, J. Young3, L. Atkins1,2, M.G. Wilmot1,2, A.J. Rintoul1,2, T. Lambert1,2, D.R. McClements2,4, P. Raper4, P. Ward1,2, C. Walton5 and T. York6 1CSIRO Centre for Environment and Life Sciences, Wembley, WA 2CRC for Plant-based Management of Dryland Salinity. 3School of Agricultural and Resource Economics, University of Western Australia. 4Department of Agriculture and Food WA. 5Condering Hills, Yealering. 6Anameka Farms, Tammin. MEAT QUALITY 3. Development of intramuscular fat in prime lambs, young sheep and beef cattle, David Pethick1, David Hopkins2 and Malcolm McPhee3,1School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA, 2NSW Department of Primary Industries, Cowra, NSW,3NSW Dept. of Primary Industries, University of New England, Armidale, NSW, 4. Importance of drinking water temperature for managing heat stress in sheep, Savage DB, Nolan JV, Godwin IR, Aoetpah A, Nguyen T, Baillie N and Lawler C University of New England, Armidale, NSW, Australia EWE MANAGEMENT TOOLS 5. E - sheep Management of Pregnant Merino Ewes and their Finishing Lambs, Ken GeentyA, John SmithA, Darryl SmithB, Tim DyallA and Grant UphillA A Sheep CRC and CSIRO Livestock Industries, Chiswick, NSW B Turretfield Research Station, SARDI, Roseworthy, SA 6. Is it important to manage ewes to CS targets? John Young, Farming Systems Analysis Service, Kojonup, WA MULESING 7. Mulesing accreditation - Vital for Wool\u27s Future, Dr Michael Paton, Department of Agriculture and Food WA, 8. Mulesing Alternatives, Jules Dorrian, Affiliation Project Manager Blowfly Control Australian Wool Inovatio
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