694 research outputs found

    Spatial Reasoning: Improvement Of Imagery And Abilities In Sophomore Organic Chemistry. Perspective To Enhance Student Learning

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    Spatial reasoning has become a demanded skill for students pursuing a science emphasis to compete with the dynamic growth of our professional society. The ability to reason spatially includes explorations in memory recollection and problem solving capabilities as well as critical thinking and reasoning skills. With these advancements, educational requirements seek reassurance in that efficient learning skills can be embedded in science curricula. Organic chemistry is a source in which abilities such as spatial reasoning can benefit students intending to thrive in scientific communities. This study of instructional development in organic chemistry seeks to determine if spatial reasoning can be improved by exposing stereo-chemical techniques from the Purdue Visualization Rotation Test (ROT) to students who have not taken organic chemistry and have science oriented educational goals. We sought to determine two purposes: to gauge how much spatial reasoning a student possessed prior to the course, and to test if spatial ability can be improved in students who present low ability over the span of the three month course. Results show significance in that spatial reasoning can be improved through statistical analysis in students who showed below average qualities

    Drugs in early clinical development for the treatment of osteosarcoma

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    Introduction: Osteosarcomas are the main malignant primary bone tumours found in children and young adults. Conventional treatment is based on diagnosis and resection surgery, combined with polychemotherapy. This is a protocol that was established in the 1970s. Unfortunately, this therapeutic approach has reached a plateau of efficacy and the patient survival rate has not improved in the last four decades. New therapeutic approaches are thus required to improve the prognosis for osteosarcoma patients. Areas covered: From the databases available and published scientific literature, the present review gives an overview of the drugs currently in early clinical development for the treatment of osteosarcoma. For each drug, a short description is given of the relevant scientific data supporting its development. Expert opinion: Multidrug targeted approaches are set to emerge, given the heterogeneity of osteosarcoma subtypes and the multitude of therapeutic responses. The key role played by the microenvironment in the disease increases the number of therapeutic targets (such as macrophages or osteoclasts), as well as the master proteins that control cell proliferation or cell death. Ongoing phase I/II trials are important steps, not only for identifying new therapies with greater safety and efficacy, but also for better defining the role played by the microenvironment in the pathogenesis of osteosarcoma

    Genetics of decayed sexual traits in a parasitoid wasp with endosymbiont-induced asexuality.

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    Trait decay may occur when selective pressures shift, owing to changes in environment or life style, rendering formerly adaptive traits non-functional or even maladaptive. It remains largely unknown if such decay would stem from multiple mutations with small effects or rather involve few loci with major phenotypic effects. Here, we investigate the decay of female sexual traits, and the genetic causes thereof, in a transition from haplodiploid sexual reproduction to endosymbiont-induced asexual reproduction in the parasitoid wasp Asobara japonica. We take advantage of the fact that asexual females cured of their endosymbionts produce sons instead of daughters, and that these sons can be crossed with sexual females. By combining behavioral experiments with crosses designed to introgress alleles from the asexual into the sexual genome, we found that sexual attractiveness, mating, egg fertilization and plastic adjustment of offspring sex ratio (in response to variation in local mate competition) are decayed in asexual A. japonica females. Furthermore, introgression experiments revealed that the propensity for cured asexual females to produce only sons (because of decayed sexual attractiveness, mating behavior and/or egg fertilization) is likely caused by recessive genetic effects at a single locus. Recessive effects were also found to cause decay of plastic sex-ratio adjustment under variable levels of local mate competition. Our results suggest that few recessive mutations drive decay of female sexual traits, at least in asexual species deriving from haplodiploid sexual ancestors

    Acceptability and facilitators of and barriers to point-of-care HIV testing in a homeless-focused service in Gloucestershire: a qualitative evaluation

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    Objectives: Late HIV diagnosis increases the risks of onward transmission, morbidity and mortality. Rapid point-of-care testing (POCT) reaches people who have never been tested and people living with HIV who are undiagnosed. This study explored the acceptability and feasibility of HIV POCT from the perspectives of service providers and users. // Methods: A pilot study introduced HIV POCT to one service in Gloucestershire, England. Eleven semi-structured interviews with service users and a focus group with three service providers were conducted. The Theoretical Framework of Acceptability and the Theoretical Domains Framework were used to design the topic guide and analysis. // Results: Acceptability of HIV POCT was high. Seven facilitators were identified (e.g. understanding the test purpose and process), alongside two potential barriers, one relevant to service providers and users (anxiety) and the other to service users (stigma). // Conclusions: To maximize the benefits of implementation of HIV POCT, health care providers require appropriate training and supervision to offer and administer POCT

    Sinking Jelly-Carbon Unveils Potential Environmental Variability along a Continental Margin

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    Particulate matter export fuels benthic ecosystems in continental margins and the deep sea, removing carbon from the upper ocean. Gelatinous zooplankton biomass provides a fast carbon vector that has been poorly studied. Observational data of a large-scale benthic trawling survey from 1994 to 2005 provided a unique opportunity to quantify jelly-carbon along an entire continental margin in the Mediterranean Sea and to assess potential links with biological and physical variables. Biomass depositions were sampled in shelves, slopes and canyons with peaks above 1000 carcasses per trawl, translating to standing stock values between 0.3 and 1.4 mg C m2 after trawling and integrating between 30,000 and 175,000 m2 of seabed. The benthopelagic jelly-carbon spatial distribution from the shelf to the canyons may be explained by atmospheric forcing related with NAO events and dense shelf water cascading, which are both known from the open Mediterranean. Over the decadal scale, we show that the jelly-carbon depositions temporal variability paralleled hydroclimate modifications, and that the enhanced jelly-carbon deposits are connected to a temperature-driven system where chlorophyll plays a minor role. Our results highlight the importance of gelatinous groups as indicators of large-scale ecosystem change, where jelly-carbon depositions play an important role in carbon and energy transport to benthic systems

    L'émotion véhiculée par le langage au service de l'apprentissage de l'orthographe

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    International audienceDes enfants scolarisés du CE1 au CM2 lisent et écoutent des histoires positives, négatives ou neutres se terminant par un pseudo-mot. Ils sont soumis après la présentation de toutes les histoires à une tâche de reconnaissance orthographique du pseudo-mot. Les résultats montrent un effet bénéfique de la valence émotionnelle dès le CE2 pour l'une ou l'autre des valences et généralisé aux deux valences au CM2. Cet effet est expliqué d'une part par la libération de ressources attentionnelles permise par l'automatisation des procédures de lecture et d'autre part par la mobilisation du système affectif et une plus grande richesse relative des représentations lexicales des mots chargés émotionnellement

    Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

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    BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

    Detection in the United Kingdom of the Neisseria gonorrhoeae FC428 clone, with ceftriaxone resistance and intermediate resistance to azithromycin, October to December 2018

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    We describe detection in the United Kingdom (UK) of the drug-resistant Neisseria gonorrhoeae FC428 clone, with ceftriaxone resistance and intermediate azithromycin resistance. Two female patients developed infection following contact with UK-resident men from the same sexual network linked to travel to Ibiza, Spain. One case failed treatment with ceftriaxone, and azithromycin and gentamicin, before successful treatment with ertapenem. Both isolates had indistinguishable whole-genome sequences. Urgent action is essential to contain this drug-resistant strain
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