1,406 research outputs found

    Increased collagen synthesis rate during wound healing in muscle

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    Wound healing in muscle involves the deposition of collagen, but it is not known whether this is achieved by changes in the synthesis or the degradation of collagen. We have used a reliable flooding dose method to measure collagen synthesis rate in vivo in rat abdominal muscle following a surgical incision. Collagen synthesis rate was increased by 480% and 860% on days 2 and 7 respectively after surgery in the wounded muscle compared with an undamaged area of the same muscle. Collagen content was increased by approximately 100% at both day 2 and day 7. These results demonstrate that collagen deposition during wound healing in muscle is achieved entirely by an increase in the rate of collagen synthesis

    Transpiration from subarctic deciduous woodlands: environmental controls and contribution to ecosystem evapotranspiration

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    Potential land‐climate feedbacks in subarctic regions, where rapid warming is driving forest expansion into the tundra, may be mediated by differences in transpiration of different plant functional types. Here we assess the environmental controls of overstorey transpiration and its relevance for ecosystem evapotranspiration in subarctic deciduous woodlands. We measured overstorey transpiration of mountain birch canopies and ecosystem evapotranspiration in two locations in northern Fennoscandia, having dense (Abisko) and sparse (Kevo) overstories. For Kevo, we also upscale chamber‐measured understorey evapotranspiration from shrubs and lichen using a detailed land cover map. Sub‐daily evaporative fluxes were not affected by soil moisture, and showed similar controls by vapour pressure deficit and radiation across sites. At the daily timescale, increases in evaporative demand led to proportionally higher contributions of overstorey transpiration to ecosystem evapotranspiration. For the entire growing season, the overstorey transpired 33% of ecosystem evapotranspiration in Abisko and only 16% in Kevo. At this latter site, the understorey had a higher leaf area index and contributed more to ecosystem evapotranspiration compared to the overstorey birch canopy. In Abisko, growing season evapotranspiration was 27% higher than precipitation, consistent with a gradual soil moisture depletion over the summer. Our results show that overstorey canopy transpiration in subarctic deciduous woodlands is not the dominant evaporative flux. However, given the observed environmental sensitivity of evapotranspiration components, the role of deciduous trees in driving ecosystem evapotranspiration may increase with the predicted increases in tree cover and evaporative demand across subarctic regions

    Implications of climate change for agricultural productivity in the early twenty-first century

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    This paper reviews recent literature concerning a wide range of processes through which climate change could potentially impact global-scale agricultural productivity, and presents projections of changes in relevant meteorological, hydrological and plant physiological quantities from a climate model ensemble to illustrate key areas of uncertainty. Few global-scale assessments have been carried out, and these are limited in their ability to capture the uncertainty in climate projections, and omit potentially important aspects such as extreme events and changes in pests and diseases. There is a lack of clarity on how climate change impacts on drought are best quantified from an agricultural perspective, with different metrics giving very different impressions of future risk. The dependence of some regional agriculture on remote rainfall, snowmelt and glaciers adds to the complexity. Indirect impacts via sea-level rise, storms and diseases have not been quantified. Perhaps most seriously, there is high uncertainty in the extent to which the direct effects of CO2 rise on plant physiology will interact with climate change in affecting productivity. At present, the aggregate impacts of climate change on global-scale agricultural productivity cannot be reliably quantified

    Secure referee selection for fair and responsive peer-to-peer gaming

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    Peer-to-Peer (P2P) architectures for Massively Multiplayer Online Games (MMOG) provide better scalability than Client/Server (C/S); however, they increase the possibility of cheating. Recently proposed P2P protocols use trusted referees that simulate/validate the game to provide security equivalent to C/S. When selecting referees from untrusted peers, selecting non-colluding referees becomes critical. Further, referees should be selected such that the range and length of delays to players is minimised (maximising game fairness and responsiveness). In this paper we formally define the referee selection problem and propose two secure referee selection algorithms, SRS-1 and SRS-2, to solve it. Both algorithms ensure the probability of corrupt referees controlling a zone/region is below a predefined limit, while attempting to maximise responsiveness and fairness. The trade-off between responsiveness and fairness is adjustable for both algorithms. Simulations of three different scenarios show the effectiveness of our algorithms

    Understanding the everyday designer in organisations

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    This paper builds upon the existing concept of an everyday designer as a non-expert designer who carries out design activities using available resources in a given environment. It does so by examining the design activities undertaken by non-expert, informal, designers in organisations who make use of the formal and informal technology already in use in organisations while designing to direct, influence, change or transform the practices of people in the organisation. These people represent a cohort of designers who are given little attention in the literature on information systems, despite their central role in the formation of practice and enactment of technology in organisations. The paper describes the experiences of 18 everyday designers in an academic setting using three concepts: everyday designer in an organisation, empathy through design and experiencing an awareness gap. These concepts were constructed through the analysis of in-depth interviews with the participants. The paper concludes with a call for tool support for everyday designers in organisations to enable them to better understand the audience for whom they are designing and the role technology plays in the organisation

    Thyroid control over biomembranes: VI. Lipids in liver mitochondria and microsomes of hypothyroid rats

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    The lipids of liver mitochondria prepared from normal rats and from rats made hypothyroid by thyroidectomy and injection with131INa contained similar amounts, per mg protein, of total lipids, phospholipids, neutral lipids and lipid phosphorus. Hypothyroidism caused a doubling of the relative amounts of mitochondrial cardiolipins (CL; to 20.5% of the phospholipid P) and an accompanying trend (although statistically not significant) toward decreased amounts of both phosphatidylcholines (PC) and phosphatidylserines (PS), with phosphatidylethanolamines (PE) remaining unchanged. The pattern of elevated 18∶2 fatty acyl content and depleted 20∶4 acyl groups of the mitochondrial phospholipids of hypothyroid preparations was reflected to varying degrees in the resolved phospholipids, with PC showing greater degrees of abnormality than PE, and CL showing none. Hypothyroidism produced the same abnormal pattern of fatty acyl distributions in liver microsomal total lipids as was found in the mitochondria. Hypothyroid rats, when killed 6 hr after injection of [1‐14C] labeled linoleate, showed the following abnormalities: the liver incorporated less label into lipids, and converted 18∶2 not exclusively to 20∶4 (as normals do) but instead incorporated the label mainly into saturated fatty acids. These data, together with the known decrease in β‐oxidation, suggest that hypothyroidism involves possible defective step(s) in the conversion of 18∶2 to 20∶4.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142296/1/lipd0328.pd

    Public-private partnerships and the politics of alcohol policy in England : the Coalition Government's Public Health 'Responsibility Deal'

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    BACKGROUND: The 2010-2015 Conservative-led Coalition Government launched their flagship Public Health Responsibility Deal (PHRD) for England in 2011; a year before their alcohol strategy. This co-regulatory regime placed alcohol industry actors at the heart of policy-making, but was viewed with scepticism by public health actors. This article examines the ways in which the PHRD structured the alcohol policy environment throughout this period, which included the rejection of evidence-based policies such as minimum unit pricing. METHODS: This article draws on 26 semi-structured interviews with policy actors (parliamentarians, civil servants, civil society actors and academics) in 2018. Respondents were identified and recruited using purposive sampling. Interviews were recorded, transcribed and analysed using thematic coding. RESULTS: The PHRD shaped the context of alcohol policy development at Westminster throughout this period. It circumscribed the policy space by taking evidence-based measures not amenable to industry partnership off the agenda. While the PHRD created important opportunities for industry engagement with policy-makers, it undermined public health actors' access to government, particularly following their withdrawal from the process. Moreover, the PHRD demonstrates the enduring appeal of partnership as a policy idea for governments, despite a lack of evidence of their effectiveness. CONCLUSIONS: This study of the PHRD demonstrates the ways in which industry actors are able to influence policy through long-term relationship building and partnership working on policy decision-making. Whilst such partnership approaches may appear to have the potential to mitigate some of alcohol harms, they create fundamental conflicts of interest, and may undermine the very causes they seek to further

    Characterization of changes in the tyrosine pathway by 24-h profiling during nitisinone treatment in alkaptonuria

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    BACKGROUND: Although changes in the tyrosine pathway during nitisinone therapy are known, a complete characterization of the induced tyrosinaemia is lacking to improve disease management. PATIENTS AND METHODS: Our research aims were addressed by 24-h blood sampling. 40 patients with alkaptonuria (AKU), treated with 0, 1, 2, 4 and 8 mg nitisinone daily (n = 8), were studied over four weeks. Serum homogentisic acid (sHGA), tyrosine (sTYR), phenylalanine (sPHE), hydroxyphenylpyruvate (sHPPA), hydroxyphenyllactate (sHPLA) and nitisinone (sNIT) were measured at baseline and after four weeks. RESULTS: sNIT showed a clear dose-proportional response. sTYR increased markedly but with less clear-cut dose responses after nitisinone. Fasting and average 24-h (C(av)) sTYR responses were similar. Individual patient sTYR 24-h profiles showed significant fluctuations during nitisinone therapy. At week 4, sTYR, sHPPA and sHPPL all showed dose-related increases compared to V0, with the greatest difference between 1 and 8 mg nitisinone seen for HPLA, while there was no change from V0 in sPHE. sHGA decreased to values around the lower limit of quantitation. DISCUSSION: There was sustained tyrosinaemia after four weeks of nitisinone therapy with significant fluctuations over the day in individual patients. Diet and degree of conversion of HPPA to HPLA may determine extent of nitisinone-induced tyrosinaemia. CONCLUSION: A fasting blood sample is recommended to monitor sTYR during nitisinone therapy Adaptations in HPPA metabolites as well as the inhibition of tyrosine aminotransferase could be contributing factors generating tyrosinaemia during nitisinone therapy

    Predictors of complications in gynaecological oncological surgery: a prospective multicentre study (UKGOSOC-UK gynaecological oncology surgical outcomes and complications)

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    Background: There are limited data on surgical outcomes in gynaecological oncology. We report on predictors of complications in a multicentre prospective study. / Methods: Data on surgical procedures and resulting complications were contemporaneously recorded on consented patients in 10 participating UK gynaecological cancer centres. Patients were sent follow-up letters to capture any further complications. Post-operative (Post-op) complications were graded (I–V) in increasing severity using the Clavien-Dindo system. Grade I complications were excluded from the analysis. Univariable and multivariable regression was used to identify predictors of complications using all surgery for intra-operative (Intra-op) and only those with both hospital and patient-reported data for Post-op complications. / Results: Prospective data were available on 2948 major operations undertaken between April 2010 and February 2012. Median age was 62 years, with 35% obese and 20.4% ASA grade ⩾3. Consultant gynaecological oncologists performed 74.3% of operations. Intra-op complications were reported in 139 of 2948 and Grade II–V Post-op complications in 379 of 1462 surgeries. The predictors of risk were different for Intra-op and Post-op complications. For Intra-op complications, previous abdominal surgery, metabolic/endocrine disorders (excluding diabetes), surgical complexity and final diagnosis were significant in univariable and multivariable regression (P<0.05), with diabetes only in multivariable regression (P=0.006). For Post-op complications, age, comorbidity status, diabetes, surgical approach, duration of surgery, and final diagnosis were significant in both univariable and multivariable regression (P<0.05). / Conclusions: This multicentre prospective audit benchmarks the considerable morbidity associated with gynaecological oncology surgery. There are significant patient and surgical factors that influence this risk
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