1,434 research outputs found

    Drone-Based Vegetation Assessment in Arid Ecosystems

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    Proof of long-term vegetation change in arid rangelands is often insufficient to influence policy, even when the change is clear to ecologists. Drones provide a way to collect unbiased evidence of plant spatiotemporal distribution at a dramatically reduced cost for the scales needed in these habitats. Assessment of phytomass spatial distribution by drone has become a routine, but further analysis requires advanced skills in data collection and post-flight processing. Accurate assessment of phytomass temporal change will require protocols to be developed for data collection and analysis. Biodiversity assessment by drone is unreliable, but there is potential for assessing phytomass change within and among taxonomic groups in arid rangelands, by repeatedly sampling areas in which perennial plants have been classified manually

    Reclaiming the political : emancipation and critique in security studies

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    The critical security studies literature has been marked by a shared commitment towards the politicization of security – that is, the analysis of its assumptions, implications and the practices through which it is (re)produced. In recent years, however, politicization has been accompanied by a tendency to conceive security as connected with a logic of exclusion, totalization and even violence. This has resulted in an imbalanced politicization that weakens critique. Seeking to tackle this situation, the present article engages with contributions that have advanced emancipatory versions of security. Starting with, but going beyond, the so-called Aberystwyth School of security studies, the argument reconsiders the meaning of security as emancipation by making the case for a systematic engagement with the notions of reality and power. This revised version of security as emancipation strengthens critique by addressing political dimensions that have been underplayed in the critical security literature

    Health services research in the public healthcare system in Hong Kong: An analysis of over 1 million antihypertensive prescriptions between 2004-2007 as an example of the potential and pitfalls of using routinely collected electronic patient data

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    <b>Objectives</b> Increasing use is being made of routinely collected electronic patient data in health services research. The aim of the present study was to evaluate the potential usefulness of a comprehensive database used routinely in the public healthcare system in Hong Kong, using antihypertensive drug prescriptions in primary care as an example.<p></p> <b>Methods</b> Data on antihypertensive drug prescriptions were retrieved from the electronic Clinical Management System (e-CMS) of all primary care clinics run by the Health Authority (HA) in the New Territory East (NTE) cluster of Hong Kong between January 2004 and June 2007. Information was also retrieved on patients’ demographic and socioeconomic characteristics, visit type (new or follow-up), and relevant diseases (International Classification of Primary Care, ICPC codes). <p></p> <b>Results</b> 1,096,282 visit episodes were accessed, representing 93,450 patients. Patients’ demographic and socio-economic details were recorded in all cases. Prescription details for anti-hypertensive drugs were missing in only 18 patients (0.02%). However, ICPC-code was missing for 36,409 patients (39%). Significant independent predictors of whether disease codes were applied included patient age > 70 years (OR 2.18), female gender (OR 1.20), district of residence (range of ORs in more rural districts; 0.32-0.41), type of clinic (OR in Family Medicine Specialist Clinics; 1.45) and type of visit (OR follow-up visit; 2.39). <p></p> In the 57,041 patients with an ICPC-code, uncomplicated hypertension (ICPC K86) was recorded in 45,859 patients (82.1%). The characteristics of these patients were very similar to those of the non-coded group, suggesting that most non-coded patients on antihypertensive drugs are likely to have uncomplicated hypertension. <p></p> <b>Conclusion</b> The e-CMS database of the HA in Hong Kong varies in quality in terms of recorded information. Potential future health services research using demographic and prescription information is highly feasible but for disease-specific research dependant on ICPC codes some caution is warranted. In the case of uncomplicated hypertension, future research on pharmaco-epidemiology (such as prescription patterns) and clinical issues (such as side-effects of medications on metabolic parameters) seems feasible given the large size of the data set and the comparability of coded and non-coded patients

    In-cell NMR characterization of the secondary structure populations of a disordered conformation of α-Synuclein within E. coli cells

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    α-Synuclein is a small protein strongly implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders. We report here the use of in-cell NMR spectroscopy to observe directly the structure and dynamics of this protein within E. coli cells. To improve the accuracy in the measurement of backbone chemical shifts within crowded in-cell NMR spectra, we have developed a deconvolution method to reduce inhomogeneous line broadening within cellular samples. The resulting chemical shift values were then used to evaluate the distribution of secondary structure populations which, in the absence of stable tertiary contacts, are a most effective way to describe the conformational fluctuations of disordered proteins. The results indicate that, at least within the bacterial cytosol, α-synuclein populates a highly dynamic state that, despite the highly crowded environment, has the same characteristics as the disordered monomeric form observed in aqueous solution

    Predicting Geographic Ranges of Marine Animal Populations Using Stable Isotopes: A Case Study of Great Hammerhead Sharks in Eastern Australia

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    © Copyright © 2020 Raoult, Trueman, Kingsbury, Gillanders, Broadhurst, Williamson, Nagelkerken, Booth, Peddemors, Couturier and Gaston. Determining the geographic range of widely dispersed or migratory marine organisms is notoriously difficult, often requiring considerable costs and typically extensive tagging or exploration programs. While these approaches are accurate and can reveal important information on the species, they are usually conducted on only a small number of individuals and can take years to produce relevant results, so alternative approaches may be preferable. The presence of latitudinal gradients in stable carbon isotope compositions of marine phytoplankton offers a means to quickly determine likely geographic population ranges of species that rely on productivity from these resources. Across sufficiently large spatial and temporal scales, the stable carbon isotopes of large coastal or pelagic marine species should reflect broad geographic patterns of resource use, and could be used to infer geographic ranges of marine populations. Using two methods, one based on a global mechanistic model and the other on targeted low-cost latitudinal sampling of fishes, we demonstrate and compare these stable isotope approaches to determine the core population geography of an apex predator, the great hammerhead (Sphyrna mokarran). Both methods indicated similar geographic ranges and suggested that S. mokarran recorded in south-eastern Australia are likely to be from more northern Australian waters. These approaches could be replicated in other areas where coastlines span predictable geographic gradients in isotope values and be used to determine the core population geography of highly mobile species to inform management decisions

    Fractures are common within 18 months following first-line R-CHOP in older patients with diffuse large B-cell lymphoma

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    Diffuse large B-cell lymphoma (DLBCL) and osteoporotic fracture are both more common in older patients. Exposure to R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) is likely to increase the risk of fracture, but evidence is lacking to define fracture incidence in this group. Data on consecutive patients with DLBCL aged ≥70 years treated with 1 to 8 cycles of full or attenuated R-CHOP were retrospectively collected across 10 UK centers (2009-2019). Patients were followed up from starting R-CHOP for a minimum of 6 months and censored at 18 months; at last follow-up if <18 months; or at progression or death. Of 877 patients identified, 148 were excluded: 121 had progression or died before 6 months; 23 had follow-up <6 months. Across 729 remaining patients, the median age was 77 years, and 68% had an Eastern Cooperative Oncology Group performance status of 0 to 1. Eighty-one fractures occurred within 18 months of follow-up; 42 were symptomatic, including 30 requiring hospital attendance or admission. The cumulative fracture incidence was 6.2% (95% confidence interval [CI], 4.7-8.2) at 6 months; 9.7% (95% CI, 7.8-12.1) at 12 months; and 11.4% (95% CI, 9.3-14.0) at 18 months. Multivariate analysis identified a predisposing history (osteoporosis, osteopenia, prior fracture, and rheumatoid arthritis [RhA]), DLBCL bone involvement at baseline, and receipt of prephase steroids as independent risk factors for fracture. There is a clinically relevant fracture risk and significant associated morbidity in older patients receiving R-CHOP. Careful attention to bone health is warranted in older patients receiving R-CHOP. Randomized studies are required to better define the most effective strategies to reduce fracture risk

    Use of Cis-[18F]Fluoro-Proline for Assessment of Exercise-Related Collagen Synthesis in Musculoskeletal Connective Tissue

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    Protein turnover in collagen rich tissue is influenced by exercise, but can only with difficulty be studied in vivo due to use of invasive procedure. The present study was done to investigate the possibility of applying the PET-tracer, cis-[18F]fluoro-proline (cis-Fpro), for non-invasive assessment of collagen synthesis in rat musculoskeletal tissues at rest and following short-term (3 days) treadmill running. Musculoskeletal collagen synthesis was studied in rats at rest and 24 h post-exercise. At each session, rats were PET scanned at two time points following injection of cis-FPro: (60 and 240 min p.i). SUV were calculated for Achilles tendon, calf muscle and tibial bone. The PET-derived results were compared to mRNA expression of collagen type I and III. Tibial bone had the highest SUV that increased significantly (p<0.001) from the early (60 min) to the late (240 min) PET scan, while SUV in tendon and muscle decreased (p<0.001). Exercise had no influence on SUV, which was contradicted by an increased gene expression of collagen type I and III in muscle and tendon. The clearly, visible uptake of cis-Fpro in the collagen-rich musculoskeletal tissues is promising for multi-tissue studies in vivo. The tissue-specific differences with the highest basal uptake in bone are in accordance with earlier studies relying on tissue incorporation of isotopic-labelled proline. A possible explanation of the failure to demonstrate enhanced collagen synthesis following exercise, despite augmented collagen type I and III transcription, is that SUV calculations are not sensitive enough to detect minor changes in collagen synthesis. Further studies including kinetic compartment modeling must be performed to establish whether cis-Fpro can be used for non-invasive in-vivo assessment of exercise-induced changes in musculoskeletal collagen synthesis
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