659 research outputs found

    Tamsiniella labiosa gen. et sp. nov., a new freshwater ascomycete from submerged wood

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    Investigations into the fungi occurring on wood submerged in freshwater ecosystems have revealed a unique, but characteristic group of fungi. In this paper a new pyrenomycete, Tamsiniella labiosa gen. et sp.nov,, is described and illustrated with light, scanning, and transmission electron micrographs. The germs has remarkable short: stipitate cylindrical asei with an internal refractive apical ring that are apically truncate and have an external thickening. Ascospores are ellipsoidal-fusiform and surrounded by a mucilaginous sheath. At the transmission electron microscope level, the annulus iv of the ascus apical apparatus is differentiated from the inner ascus wail layer and is composed of horizontally oriented, eiectron-dense fibrillar material. A narrow plug is present in the centre of the apical ring. An electron-dense amorphous regk oecurs between the outer ascus wall layer and the annulus part of the apical apparatus. The outer ascus wail layer is lacking a the apex. The ultrastructure of the ascus apex differs from those described in the Lasiosphaeriaceae, Sordariaceae, and Xylariaceae.published_or_final_versio

    Theoretical basis and practical aspects of small specimen creep testing

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    Interest in and the application of small specimen creep test techniques are increasing. This is because it is only possible to obtain small samples of material in some situations, for example, the scoop samples that are removed from in-service components, the heat-affected zones that are created when welds are used to join components and the desire to produce only small amounts of material in alloy development programmes. It is therefore important to review and compare the theoretical basis and practical aspects of each of the small specimen creep testing methods, in order to clearly understand which of the methods is the best for any specific application. This article provides the theoretical basis for each commonly used test method

    Tirisporella gen. nov., an ascomycete from the mangrove palm Nypa fruticans

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    Tirisporella beccariana comb.nov. is redescribed from decomposing leaf petiole (or rachis) bases of Nypa fruticans recently collected in Malaysia and the Philippiines. The superficial ascomata bear bitunicate asci with (3-)5(-7)-septate ascospores that are brown and verrucose, except for the prominent hyaline basal cell, and furnished with a distinctive apical appendage that arises from the spore wall. Te ultrastructure of the fungus is contrasted with that of species of Corollospora and Corallicola, with particular reference to the mode of ascospore appendage formation. The species was originally described from a Sarawak collection as Sphaeria becariana and later transferred to Melanomma and given the new name Melanomma cesatianum. Gibberidea nipae is a synonym. The recent collections were compared with type specimens. The fungus is not properly placed in Melanomma or Gibberidea or other known genera and a new genus Tiriporella is described.published_or_final_versio

    Lithium Intercalation into the Excitonic Insulator Candidate Ta2NiSe5

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    A new reduced phase derived from the excitonic insulator candidate Ta2NiSe5 has been synthesized via the intercalation of lithium. LiTa2NiSe5 crystallizes in the orthorhombic space group Pmnb (no. 62) with lattice parameters a = 3.50247(3) Ă…, b = 13.4053(4) Ă…, c = 15.7396(2) Ă…, and Z = 4, with an increase of the unit cell volume by 5.44(1)% compared with Ta2NiSe5. Significant rearrangement of the Ta-Ni-Se layers is observed, in particular a very significant relative displacement of the layers compared to the parent phase, similar to that which occurs under hydrostatic pressure. Neutron powder diffraction experiments and computational analysis confirm that Li occupies a distorted triangular prismatic site formed by Se atoms of adjacent Ta2NiSe5 layers with an average Li-Se bond length of 2.724(2) Ă…. Li-NMR experiments show a single Li environment at ambient temperature. Intercalation suppresses the distortion to monoclinic symmetry that occurs in Ta2NiSe5 at 328 K and that is believed to be driven by the formation of an excitonic insulating state. Magnetometry data show that the reduced phase has a smaller net diamagnetic susceptibility than Ta2NiSe5 due to the enhancement of the temperature-independent Pauli paramagnetism caused by the increased density of states at the Fermi level evident also from the calculations, consistent with the injection of electrons during intercalation and formation of a metallic phase

    Sex differences in mathematics and reading achievement are inversely related: within- and across-nation assessment of 10 years of PISA data

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    We analyzed one decade of data collected by the Programme for International Student Assessment (PISA), including the mathematics and reading performance of nearly 1.5 million 15 year olds in 75 countries. Across nations, boys scored higher than girls in mathematics, but lower than girls in reading. The sex difference in reading was three times as large as in mathematics. There was considerable variation in the extent of the sex differences between nations. There are countries without a sex difference in mathematics performance, and in some countries girls scored higher than boys. Boys scored lower in reading in all nations in all four PISA assessments (2000, 2003, 2006, 2009). Contrary to several previous studies, we found no evidence that the sex differences were related to nations’ gender equality indicators. Further, paradoxically, sex differences in mathematics were consistently and strongly inversely correlated with sex differences in reading: Countries with a smaller sex difference in mathematics had a larger sex difference in reading and vice versa. We demonstrate that this was not merely a between-nation, but also a within-nation effect. This effect is related to relative changes in these sex differences across the performance continuum: We did not find a sex difference in mathematics among the lowest performing students, but this is where the sex difference in reading was largest. In contrast, the sex difference in mathematics was largest among the higher performing students, and this is where the sex difference in reading was smallest. The implication is that if policy makers decide that changes in these sex differences are desired, different approaches will be needed to achieve this for reading and mathematics. Interventions that focus on high-achieving girls in mathematics and on low achieving boys in reading are likely to yield the strongest educational benefits

    Prepared to practice? Perception of career preparation and guidance of recent medical graduates at two campuses of a transnational medical school: a cross-sectional study.

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    BACKGROUND: Graduating medical students enter the workforce with substantial medical knowledge and experience, yet little is known about how well they are prepared for the transition to medical practice in diverse settings. We set out to compare perceptions of medical school graduates\u27 career guidance with their perceptions of preparedness to practice as interns. We also set out to compare perceptions of preparedness for hospital practice between graduates from two transnational medical schools. METHODS: This was a cross-sectional study. A Preparedness for Hospital Practice (PHPQ) survey and career guidance questionnaire was sent to recent medical graduates, incorporating additional free text responses on career preparation. Data was analyzed using descriptive statistics and tests of association including Chi-square, Mann-Whitney U and Kruskal-Wallis H tests. RESULTS: Forty three percent (240/555) of graduates responded to the survey: 39 % of respondents were domestic (Dublin, Ireland or Manama, Kingdom of Bahrain) and interning locally; 15 % were overseas students interning locally; 42 % were overseas students interning internationally and 4 % had not started internship. Two variables explained 13 % of the variation in preparedness for hospital practice score: having planned postgraduate education prior to entering medical school and having helpful career guidance in medical school. Overseas graduates interning internationally were more likely to have planned their postgraduate career path prior to entering medical school. Dublin graduates found their career guidance more helpful than Bahrain counterparts. The most cited shortcomings were lack of structured career advice and lack of advice on the Irish and Bahraini postgraduate systems. CONCLUSIONS: This study has demonstrated that early consideration of postgraduate career preparation and helpful medical school career guidance has a strong association with perceptions of preparedness of medical graduates for hospital practice. In an era of increasing globalization of medical education, these findings can direct ongoing efforts to ensure all medical students receive career guidance and preparation for internship appropriate to their destination

    Subclavian thrombosis in a patient with advanced lung cancer: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Lung cancer is now considered the most common cause of death among cancer patients. Although target biological regimens have emerged in recent years for non-small cell lung carcinoma, the survival and quality of life of patients with this condition still remain low. The five-year survival rate for all stages of lung cancer is 17% or less.</p> <p>Case presentation</p> <p>We describe the case of a 53-year-old Caucasian woman who was diagnosed with advanced stage IIIa (T2aN<sub>2</sub>M<sub>0</sub>) non-small cell lung carcinoma (adenocarcinoma) and underwent a complete left upper lobectomy three years ago. After two and a half years of follow-up, she suddenly presented with facial edema and venous distension and was immediately treated for superior vena cava syndrome. Because of a diagnostic check, a major clot was detected in the right subclavian vein. Our patient was informed about treatment options, and she was taken to the catheterization laboratory for percutaneous stenting of the superior vena cava to restore superior vena cava patency.</p> <p>Conclusion</p> <p>Lung cancer has a vast number of complications. Superior vena cava syndrome and thrombosis should be considered upon the presentation of a patient with obstructive symptoms. In this case report, even though we expected the clot to be on the side of the former lesion, it was present on the opposite side. Treatment should also start immediately in these patients with clinical suspicion of thrombosis to avoid further complications, even in cases with a differential diagnosis problem. Finally, although patients with non-small cell lung carcinoma have a high incidence of thromboembolic events, anticoagulant treatment is given only as maintenance therapy after a first event occurs.</p

    Religion's Role in Promoting Health and Reducing Risk Among American Youth

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    Although past research has long documented religion's salutary impact on adult health-related behaviors and outcomes, relatively little research has examined the relationship between religion and adolescent health. This study uses large, nationally representative samples of high school seniors to examine the relationship between religion and behavioral predictors of adolescent morbidity and mortality. Relative to their peers, religious youth are less likely to engage in behaviors that compromise their health (e.g., carrying weapons, getting into fights, drinking and driving) and are more likely to behave in ways that enhance their health (e.g., proper nutrition, exercise, and rest). Multivariate analyses suggest that these relationships persist even after controlling for demographic factors, and trend analyses reveal that they have existed over time. Particularly important is the finding that religious seniors have been relatively unaffected by past and recent increases in marijuana use.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66995/2/10.1177_109019819802500604.pd

    Countries with Higher Levels of Gender Equality Show Larger National Sex Differences in Mathematics Anxiety and Relatively Lower Parental Mathematics Valuation for Girls.

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    Despite international advancements in gender equality across a variety of societal domains, the underrepresentation of girls and women in Science, Technology, Engineering, and Mathematics (STEM) related fields persists. In this study, we explored the possibility that the sex difference in mathematics anxiety contributes to this disparity. More specifically, we tested a number of predictions from the prominent gender stratification model, which is the leading psychological theory of cross-national patterns of sex differences in mathematics anxiety and performance. To this end, we analyzed data from 761,655 15-year old students across 68 nations who participated in the Programme for International Student Assessment (PISA). Most importantly and contra predictions, we showed that economically developed and more gender equal countries have a lower overall level of mathematics anxiety, and yet a larger national sex difference in mathematics anxiety relative to less developed countries. Further, although relatively more mothers work in STEM fields in more developed countries, these parents valued, on average, mathematical competence more in their sons than their daughters. The proportion of mothers working in STEM was unrelated to sex differences in mathematics anxiety or performance. We propose that the gender stratification model fails to account for these national patterns and that an alternative model is needed. In the discussion, we suggest how an interaction between socio-cultural values and sex-specific psychological traits can better explain these patterns. We also discuss implications for policies aiming to increase girls' STEM participation
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