1,720 research outputs found

    Does Micro-CT scanning damage DNA in museum specimens?

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    X-ray micro-computed tomography and DNA sequencing are useful and increasingly common tools in taxonomy and collections research. Whilst the benefits of each method are continually evaluated and debated individually, how the methods impact each other requires more attention. We compared DNA fragment length and the barcode sequence CO1 in samples throughout a CT-scanning protocol, for a range of X-ray exposures and energies. We found no evidence of DNA damage, but advise caution when using precious or archival material, highlighting the need for further investigations and considering potential areas for research.NatSCA supports open access publication as part of its mission is to promote and support natural science collections. NatSCA uses the Creative Commons Attribution License (CCAL) http://creativecommons.org/licenses/by/2.5/ for all works we publish. Under CCAL authors retain ownership of the copyright for their article, but authors allow anyone to download, reuse, reprint, modify, distribute, and/or copy articles in NatSCA publications, so long as the original authors and source are cited. The attached file is the published version of the article

    Health ManagementInformation Systems for Resource Allocation and Purchasing in Developing Countries

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    World Bank, Health Nutrition and Population, Discussion Paper: The paper begins with the premise that it is not possible to implement an efficient, modern RAP strategy today without the effective use of information technology. The paper then leads the architect through the functionality of the systems components and environment needed to support RAP, pausing to justify them at each step. The paper can be used as a long-term guide through the systems development process as it is not necessary (and likely not possible) to implement all functions at once. The paper’s intended audience is those members of a planning and strategy body, working in conjunction with technical experts, who are charged with designing and implementing a RAP strategy in a developing country

    Effect of filtration on rolling-element-bearing life in contaminated lubricant environment

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    Fatigue tests were conducted on groups of 65 millimeter-bore ball bearings under four levels of filtration with and without a contaminated MIL-L-23699 lubricant. The baseline series used noncontaminated oil with 49 micron absolute filtration. In the remaining tests contaminants of the composition found in aircraft engine filters were injected into the filter's supply line at a constant rate of 125 milligrams per bearing-hour. The test filters had absolute particle removal ratings of 3, 30, 49, and 105 microns (0.45, 10, 30, and 70 microns nominal), respectively. Bearings were tested at 15,000 rpm under 4580 newtons radial load. Bearing life and running tract condition generally improved with finer filtration. The 3 and 30 micron filter bearings in a contaminated lubricant had statistically equivalent lives, approaching those from the baseline tests. The experimental lives of 49 micron bearings were approximately half the baseline bearing's lives. Bearings tested with the 105 micron filter experienced wear failures. The degree of surface distress, weight loss, and probable failure mode were found to be dependent on filtration level, with finer filtration being clearly beneficial

    Technical innovation changes standard radiographic protocols in veterinary medicine: is it necessary to obtain two dorsoproximal-palmarodistal oblique views of the equine foot when using computerised radiography systems?

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    Since the 1950s, veterinary practitioners have included two separate dorsoproximal–palmarodistal oblique (DPr–PaDiO) radiographs as part of a standard series of the equine foot. One image is obtained to visualise the distal phalanx and the other to visualise the navicular bone. However, rapid development of computed radiography and digital radiography and their post-processing capabilities could mean that this practice is no longer required. The aim of this study was to determine differences in perceived image quality between DPr–PaDiO radiographs that were acquired with a computerised radiography system with exposures, centring and collimation recommended for the navicular bone versus images acquired for the distal phalanx but were subsequently manipulated post-acquisition to highlight the navicular bone. Thirty images were presented to four clinicians for quality assessment and graded using a 1–3 scale (1=textbook quality, 2=diagnostic quality, 3=non-diagnostic image). No significant difference in diagnostic quality was found between the original navicular bone images and the manipulated distal phalanx images. This finding suggests that a single DPr–PaDiO image of the distal phalanx is sufficient for an equine foot radiographic series, with appropriate post-processing and manipulation. This change in protocol will result in reduced radiographic study time and decreased patient/personnel radiation exposure

    From the surface to the seafloor: How giant larvaceans transport microplastics into the deep sea.

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    Plastic waste is a pervasive feature of marine environments, yet little is empirically known about the biological and physical processes that transport plastics through marine ecosystems. To address this need, we conducted in situ feeding studies of microplastic particles (10 to 600 ÎŒm in diameter) with the giant larvacean Bathochordaeus stygius. Larvaceans are abundant components of global zooplankton assemblages, regularly build mucus "houses" to filter particulate matter from the surrounding water, and later abandon these structures when clogged. By conducting in situ feeding experiments with remotely operated vehicles, we show that giant larvaceans are able to filter a range of microplastic particles from the water column, ingest, and then package microplastics into their fecal pellets. Microplastics also readily affix to their houses, which have been shown to sink quickly to the seafloor and deliver pulses of carbon to benthic ecosystems. Thus, giant larvaceans can contribute to the vertical flux of microplastics through the rapid sinking of fecal pellets and discarded houses. Larvaceans, and potentially other abundant pelagic filter feeders, may thus comprise a novel biological transport mechanism delivering microplastics from surface waters, through the water column, and to the seafloor. Our findings necessitate the development of tools and sampling methodologies to quantify concentrations and identify environmental microplastics throughout the water column

    Problematika Tergeneralisirnya Saniri Negeri Menjadi Badan Permusyawaratan Desa

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    Regulasi Desa di Indonesia telah menggeneralisir saniri negeri menjadi sama dengan badan Permusyawaratan Desa (BPD), padahal konstruksi Saniri Negeri berbeda dengan konstruksi BPD. Penelitian ini bertujuan menganalisis masalah dalam regulasi desa di Indonesia khususnya yang mengatur tentang saniri negeri dan menganalisis konsekuensi yuridis tergeneralisirnya saniri negeri menjadi BPD, metode penelitian yang digunakan adalah yuridis normatif. Hasil penelitian menunjukkan bahwa berdasarkan rumusan norma Badan Permusyawaratan Desa (BPD) atau yang disebut dengan nama lain yang memiliki wewenang untuk membuat peraturan desa, dan mengawasi penyelenggaraan pemerintahan desa. Saniri Negeri merupakan suatu sistem kekuasaan dan terlembaga dalam 2 (dua) lembaga yaitu saniri rajapatti yang melaksanakan pemerintahan dan saniri lengkap yang merumuskan kebijakan, serta 1 (satu) forum yaitu saniri besar sebagai forum pertanggungjawaban pemerintah negeri. Saniri Negeri bukanlah lembaga sehingga berbeda dengan BPD. Perlu dilakukan sinkronisasi keberadaan BPD dengan Saniri Negeri, agar konstruksi saniri negeri tidak digeneralisasi menjadi sama dengan konstruksi BPD.

    Editors’ Note

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    Editors’ Not

    Pensions and the health of older people in South Africa: Is there an effect?

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    This paper critically reviews evidence from low and middle income countries that pensions are associated with better health outcomes for older people. It draws on new, nationally representative survey data from South Africa to provide a systematic analysis of pension effects on health and quality of life. It reports significant associations with the frequency of health service utilisation, as well as with awareness and treatment of hypertension. There is, however, no association with actual control of hypertension, self-reported health or quality of life. The paper calls for a more balanced and integrated approach to social protection for older people
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