60 research outputs found

    β decay of odd-A As to Ge isotopes in the interacting boson-fermion model

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    The structure of odd-mass isotopes of As and Ge is described in the framework of the proton-neutron interacting boson-fermion model. The energy levels and the electromagnetic properties of 69, 71, 73As and 69, 71, 73Ge are calculated and compared with the experiment. The beta-decay rates from the As isotopes to the Ge isotopes are calculated. The calculated decays tend to be stronger than the observed ones. This may indicate a mixture of components outside the model space in the wave functions of actual nuclei. The effect of the higher-order terms in the decay operators seems small

    β decay of the even-even 124Ba nucleus: A test for the interacting boson-fermion-fermion model

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    IBFFM is applied to β decay of 124Ba to 124Cs. The interacting boson-fermion-fermion model approach to β decay is applied to the decay from the even-even 124Ba to the odd-odd 124Cs nucleus. The theoretical results for energy levels, electromagnetic properties and β decay rates are compared with experimental data for 124Cs. The calculated β-decay rates demonstrate that the interacting boson approximation can be applied in the description of β decays from even-even to odd-odd nuclei

    β decay of odd-A Cs isotopes in the interacting boson-fermion model

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    The structure of odd-mass isotopes of Cs and Xe is described in the framework of IBFM. The model provides a consistent description of beta decay from Cs to Xe nuclei of mass number A = 125, 127, and 129

    Loss of genetic diversity and increased embryonic mortality in non-native lizard populations

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    Many populations are small and isolated with limited genetic variation and high risk of mating with close relatives. Inbreeding depression is suspected to contribute to extinction of wild populations, but the historical and demographic factors that contribute to reduced population viability are often difficult to tease apart. Replicated introduction events in non-native species can offer insights into this problem because they allow us to study how genetic variation and inbreeding depression are affected by demographic events (e.g. bottlenecks), genetic admixture and the extent and duration of isolation. Using detailed knowledge about the introduction history of 21 nonnative populations of the wall lizard Podarcis muralis in England, we show greater loss of genetic diversity (estimated from microsatellite loci) in older populations and in populations from native regions of high diversity. Loss of genetic diversity was accompanied by higher embryonic mortality in non-native populations, suggesting that introduced populations are sufficiently inbred to jeopardize long-term viability. However, there was no statistical correlation between population-level genetic diversity and average embryonic mortality. Similarly, at the individual level, there was no correlation between female heterozygosity and clutch size, infertility or hatching success, or between embryo heterozygosity and mortality. We discuss these results in the context of human-mediated introductions and how the history of introductions can play a fundamental role in influencing individual and population fitness in non-native species

    Technical and Clinical Outcome of Talent versus Endurant Endografts for Endovascular Aortic Aneurysm Repair

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    The technical evolution of endografts for the interventional management of infrarenal abdominal aortic aneurysms (AAA) has allowed a continuous expansion of indications. This study compares the established Talent endograft with its successor, the Endurant endograft, taking individual aortoiliac anatomy into account.From June 2007 to December 2010, 35 patients with AAA were treated with a Talent endograft (33 men) and 36 patients with an Endurant endograft (34 men). Aortoiliac anatomy was evaluated in detail using preinterventional computed tomography angiography. The 30-day outcome of both groups were compared regarding technical and clinical success as well as complications including endoleaks.The Endurant group included more patients with unfavorable anatomy (kinking of pelvic arteries, p = 0.017; shorter proximal neck, p = 0.084). Primary technical success was 91.4% in the Talent group and 100% in the Endurant group (p = 0.115). Type 1 endoleaks occurred in 5.7% of patients in the Talent group and in 2.8% of those in the Endurant group (p = 0.614). Type 3 endoleaks only occurred in the Talent group (2.9% of patients; p = 0.493). Type 2 endoleaks were significantly less common in the Endurant group than in the Talent group (8.3% versus 28.6%; p = 0.035). Rates of major and minor complications were not significantly different between both groups. Primary clinical success was significantly better in the Endurant group (97.2%) than in the Talent group (80.0%) (p = 0.028).Endurant endografts appear to have better technical and clinical outcome in patients with difficult aortoiliac anatomy, significantly reducing the occurrence of type 2 endoleaks

    Morphological characterization of the blood cells in the endangered Sicilian endemic pond turtle,Emys trinacris(Testudines: Emydidae)

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    In this study, measurements of morphological parameters, sizes and frequencies of peripheral blood cells (erythrocytes, leukocytes, thrombocytes) on blood smear preparation devices stained with May-Grünwald stain were evaluated for both sexes in 20 Emys trinacris (Testudines: Emydidae) specimens. Erythrocytes were higher in male than in female specimens. The leukocyte of E. trinacris contains eosinophil, basophil, monocyte, heterophil and lymphocyte. The eosinophil was higher in males than in females whereas lymphocytes were higher in females than in males. The erythrocyte morphological parameters (EL [erythrocyte length], EW [erythrocyte width], L/W [length/width], ES [erythrocyte size]) were compared with the same data from Emys orbicularis s.l, and from species belonging to other chelonian genera. The erythrocyte size did not vary within the studied Palearctic Emys taxa, whereas it proved to differ from that observed in other chelonians

    Threatened and extinct amphibians and reptiles in Italian natural history collections are useful conservation tools

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    Natural history museums are irreplaceable tools to study and preserve the biological diversity around the globe and among the primary actors in the recognition of species and the logical repositories for their type specimens. In this paper we surveyed the consistency of the preserved specimens of amphibians and reptiles housed in the major Italian scientific collections, and verified the presence of threatened species according to the IUCN Red List, includ-ing the Extinct (EX), Extinct in the Wild (EW), Critically Endangered (CR), Endangered (EN), and Vulnerable (VU) categories. Altogether, we analyzed 39 Italian zoological collections. We confirmed the presence of one extinct reptile (Chioninia coctei) and five extinct or extinct in the wild amphibian species (Atelopus longirostris, Nectophrynoides asperginis, Pseudophilautus leucorhinus, P. nasutus, and P. variabilis). Seven CR amphibians, fourteen CR reptile species and the extinct skink C. coctei are shared by more than one institution. Museums which host the highest number of threatened and extinct amphibian species are respectively Turin (17 CR and 1 EX), Florence (13 CR and 1 EX), and Trento (15 CR and 1 EW), while for reptiles the richest museums are those from Genoa (15 CR and 1 EX), Florence (11 CR and 1 EX), and Pisa (7 CR). Finally, we discussed the utility of natural history museums and the strategies to follow for the implementation of their functionality. © Firenze University Press

    Hubungan Antara Perhatian Orangtua Dan Hasil Belajar Pada Pembelajaran Tematik Integratif Siswa Kelas IV SD Negeri Kembangarum 2 Mranggen Demak

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    More less the studying result of students in 4th SD Negeri Kembangarum 2 Mranggen that influences some aspects, one of aspects is her parents?óÔé¼Ôäó not careless with them. Parents?óÔé¼Ôäó is constitute the?é?á first educator for children so that her parents?óÔé¼Ôäó has have responsibility to the studying result her children. The problem in this research contents is about Is there any correlation between of parents?óÔé¼Ôäó attention and the study result for thematic integrative learning in 4th SD Negeri Kembangarum 2 Mranggen Demak?. The hypothesis is that there is positive and significant correlation between of parents?óÔé¼Ôäó attention and the study result for thematic integrative learning in 4th SD Negeri Kembangarum 2 Mranggen Demak. The kind of this research is quantitative research. This research use correlation methode and submited the data use questionnaire and test. The colected data are analysed using product moment formula. The finding is that > on significancy level of 0,05. So the?é?á conclusion is there is positive and significant correlation between of parents?óÔé¼Ôäó attention and the study result for thematic integrative learning in 4th SD Negeri Kembangarum 2 Mranggen Demak

    Ensino e Aprendizagem de Matemática Através da Resolução de Problemas Como Prática Sociointeracionista

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    Resumo Neste artigo apresentamos uma experiência efetivamente prática e a abordagem do Ensino e da Aprendizagem de Matemática através da Resolução de Problemas, como prática sociointeracionista, desde suas constituições teórica e filosófica à sua prática educacional em um curso do Programa Nacional de Acesso ao Ensino Técnico e ao Emprego, dirigido pelo Instituto Federal de São Paulo – Campus Sertãozinho. Apresentamos um campo de estudo social, histórico e cultural como proposta da Resolução de Problemas, não apenas como uma metodologia de ensino-aprendizagem, mas sim como um campo de estudos que mantém vivo o movimento de ação/reflexão/ação por meio de conceitos e problemas da obra de Vygotsky. Lançamos mão dos elementos da autorregulação e metacognição pelo pensar-em-alta-voz na construção do conhecimento e na constituição da aprendizagem, além de alguns desdobramentos dessa prática no âmbito escolar
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