2,499 research outputs found

    Diversity in the organization of elastin bundles and intramembranous muscles in bat wings

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    Unlike birds and insects, bats fly with wings composed of thin skin that envelops the bones of the forelimb and spans the area between the limbs, digits, and sometimes the tail. This skin is complex and unusual; it is thinner than typical mammalian skin and contains organized bundles of elastin and embedded skeletal muscles. These elements are likely responsible for controlling the shape of the wing during flight and contributing to the aerodynamic capabilities of bats. We examined the arrangement of two macroscopic architectural elements in bat wings, elastin bundles and wing membrane muscles, to assess the diversity in bat wing skin morphology. We characterized the plagiopatagium and dactylopatagium of 130 species from 17 families of bats using cross‐polarized light imaging. This method revealed structures with distinctive relative birefringence, heterogeneity of birefringence, variation in size, and degree of branching. We used previously published anatomical studies and tissue histology to identify birefringent structures, and we analyzed their architecture across taxa. Elastin bundles, muscles, neurovasculature, and collagenous fibers are present in all species. Elastin bundles are oriented in a predominantly spanwise or proximodistal direction, and there are five characteristic muscle arrays that occur within the plagiopatagium, far more muscle than typically recognized. These results inform recent functional studies of wing membrane architecture, support the functional hypothesis that elastin bundles aid wing folding and unfolding, and further suggest that all bats may use these architectural elements for flight. All species also possess numerous muscles within the wing membrane, but the architecture of muscle arrays within the plagiopatagium varies among families. To facilitate present and future discussion of these muscle arrays, we refine wing membrane muscle nomenclature in a manner that reflects this morphological diversity. The architecture of the constituents of the skin of the wing likely plays a key role in shaping wings during flight

    Characteristics and a New Soil Classification of Key Soils Developed in the Old Reddish Chestnut Zone of Oklahoma

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    The Oklahoma Agricultural Experiment Station periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311

    Characterization of Representative Grassland and Slickspot Soils in Oklahoma

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    The Oklahoma Agricultural Experiment Station periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311

    Shrink-Swell and Other Characteristics of Five Benchmark Soils of Western Oklahoma

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    The Oklahoma Agricultural Experiment Station periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311

    Waking up to sleepiness: Modafinil, the media and the pharmaceuticalisation of everyday/night life

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    This paper examines the social construction of the new wakefulness-promoting drug Modafinil (brand name Provigil) in the British press. Key themes in this newspaper coverage include the potential 'uses' and 'abuses' of this drug in relation to: (i) medical conditions; (ii) lifestyle choices; (iii) military operations; and (iv) sporting competition. The British press, we show, play a dual role in reporting on these trends and developments: on the one hand constructing this as something of a 'wonder drug' in relation to the treatment of a number of medical complaints or conditions, on the other hand articulating and amplifying a range of cultural concerns and anxieties about the non-medical 'uses' and 'abuses' of this drug, both now and in the future. These issues, it is argued, are best interpreted in terms of media concerns over the pharmaceuticalisation rather than the medicalisation of everyday/night life. The paper concludes with some further thoughts and reflections on these issues, including the potential reworking of notions of 'pharmaceutical Calvinism' and the 'elective affinity' between this 'smart' new drug and the spirit of (bio)capitalism

    Roadside erosion control - final report

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    Experiments along Oklahoma highways on various soil materials and in the laboratory were established to find: (a) the best methods to establish bermudagrass by vegetative means; (b) the most satisfactory means of establishing grasses from seed; (c) the effect of ecological factors on species adaptation and use for erosion control , and (d) the most desirable ground cover species for erosion control and beautification.Final ReportN

    Characterization of polyether-poly(methyl methacrylate)-lithium perchlorate blend electrolytes

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    Em publicaçãoSolid polymer electrolytes (SPEs) systems based on interpenetrating blends of poly(ethylene oxide-co-propylene oxide) and poly(methyl methacrylate) host matrices, with lithium perchlorate as guest salt, were prepared. These electrolytes were presented as free-standing films, and their thermal and electrochemical properties were characterized by conductivity and electrochemical stability measurements. The properties of the interpenetrating blends of poly(ethylene oxide-co-propylene oxide) and poly(methyl methacrylate) host matrices as the electrolyte component of a solid-state electrochromic device are reported and the results obtained suggest that this electrolyte provides an encouraging performance in this application. The most conducting electrolyte composition of this SPE system is the formulation designated as SPE2-0PC (5.01x10-4 S cm-1 at about 57ÂșC). The lowest decomposition temperature was registered with the SPE6-15PC composition (233ÂșC). The average transmittance in the visible region of the spectrum was above 41% for all the samples analyzed. After coloration the device assembled with 71 wt% PC presented an average transmittance of 15.71% and an optical density at 550nm of 0.61.Fundação para a CiĂȘncia e a Tecnologia (FCT

    Chlamydia control activities in Europe: cross-sectional survey

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    Background: Chlamydia is the most commonly reported bacterial sexually transmitted infection in Europe. The objective of the Screening for Chlamydia in Europe (SCREen) project was to describe current and planned chlamydia control activities in Europe. Methods: The authors sent a questionnaire asking about different aspects of chlamydia epidemiology and control to public health and clinical experts in each country in 2007. The principles of sexually transmitted infection control were used to develop a typology comprising five categories of chlamydia control activities. Each country was assigned to a category, based on responses to the questionnaire. Results: Experts in 29 of 33 (88%) invited countries responded. Thirteen of 29 countries (45%) had no current chlamydia control activities. Six countries in this group stated that there were plans to introduce chlamydia screening programmes. There were five countries (17%) with case management guidelines only. Three countries (10%) also recommended case finding amongst partners of diagnosed chlamydia cases or people with another sexually transmitted infection. Six countries (21%) further specified groups of asymptomatic people eligible for opportunistic chlamydia testing. Two countries (7%) reported a chlamydia screening programme. There was no consistent association between the per capita gross domestic product of a country and the intensity of chlamydia control activities (P = 0.816). Conclusion: A newly developed classification system allowed the breadth of ongoing national chlamydia control activities to be described and categorized. Chlamydia control strategies should ensure that clinical guidelines to optimize chlamydia diagnosis and case management have been implemented before considering the appropriateness of screening programmes

    Software defect prediction: do different classifiers find the same defects?

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    Open Access: This article is distributed under the terms of the Creative Commons Attribution 4.0 International License CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.During the last 10 years, hundreds of different defect prediction models have been published. The performance of the classifiers used in these models is reported to be similar with models rarely performing above the predictive performance ceiling of about 80% recall. We investigate the individual defects that four classifiers predict and analyse the level of prediction uncertainty produced by these classifiers. We perform a sensitivity analysis to compare the performance of Random Forest, NaĂŻve Bayes, RPart and SVM classifiers when predicting defects in NASA, open source and commercial datasets. The defect predictions that each classifier makes is captured in a confusion matrix and the prediction uncertainty of each classifier is compared. Despite similar predictive performance values for these four classifiers, each detects different sets of defects. Some classifiers are more consistent in predicting defects than others. Our results confirm that a unique subset of defects can be detected by specific classifiers. However, while some classifiers are consistent in the predictions they make, other classifiers vary in their predictions. Given our results, we conclude that classifier ensembles with decision-making strategies not based on majority voting are likely to perform best in defect prediction.Peer reviewedFinal Published versio

    A latent class analysis of change and continuity in adolescent health and wellbeing in England during the decline in youth alcohol consumption: a repeat cross-sectional study

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    In England, the proportion of 13-15 year-olds who have ever drunk alcohol fell from 71% in 1999 to 35% in 2019. Despite substantial research literature studying this decline, we know little about connections with concurrent shifts in wider aspects of health and wellbeing. This paper aims to identify how indicators of health and wellbeing cluster within 15-year-olds in England, identify changes in clustering over time, and explore associations with sex and family affluence. We used latent class analysis of cross-sectional data from the Health Behaviours in School-aged Children study (n=5,942; four waves 2001/02-2013/14). Classes were defined by indicators of substance use, sexual activity, diet, exercise, school-related measures, e-media use, parental relationships, and wellbeing. We identified three classes, which we labelled Overall unhealthy, Substance abstainers with behavioural risk indicators, and Overall healthy. The probability of being in the Overall unhealthy class fell (2001/02: 0.39; 2013/14: 0.18) while the probability of being in the Overall healthy class increased (0.21 to 0.41). The probability of weekly alcohol use fell in all classes (e.g. Overall unhealthy: 0.71 to 0.28). Females (female vs male OR: 1.74 95%CI: 1.30 – 2.34) and those with low family affluence (high vs low family affluence OR: 0.18 95%CI: 0.08 – 0.44) had significantly higher odds of being in the Overall unhealthy class. Overall, adolescents became more likely to have co-occurring indicators of good health and wellbeing, including reduced alcohol consumption, sexual activity and cigarette smoking. However, girls and those from poorer families remained more likely to have poor health and wellbeing
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