194 research outputs found

    The SPEDE spectrometer

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    The electron spectrometer, SPEDE, has been developed and will be employed in conjunction with the Miniball spectrometer at the HIE-ISOLDE facility, CERN. SPEDE allows for direct measurement of internal conversion electrons emitted in-flight, without employing magnetic fields to transport or momentum filter the electrons. Together with the Miniball spectrometer, it enables simultaneous observation of {\gamma} rays and conversion electrons in Coulomb-excitation experiments using radioactive ion beams

    Motivation of university and non-university stakeholders to change medical education in Vietnam

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    Background. Both university and non-university stakeholders should be involved in the process of curriculum development in medical schools, because all are concerned with the competencies of the graduates. That may be difficult unless appropriate strategies are used to motivate each stakeholder. From 1999 to 2006, eight medical schools in Vietnam worked together to change the curriculum and teaching for general medical students to make it more community oriented. This paper describes the factors that motivated the different stakeholders to participate in curriculum change and teaching in Vietnamese medical schools and the activities to address those factors and have sustainable contributions from all relevant stakeholders. Methods. Case study analysis of contributions to the change process, using reports, interviews, focus group discussions and surveys and based on Herzberg's Motivation Theory to analyze involvement of different stakeholders. Results. Different stakeholders were motivated by selected activities, such as providing opportunities for non-university stakeholders to share their opinions, organizing interactions among university stakeholders, stimulating both bottom-up and top-down inputs, focusing on learning from each other, and emphasizing self-motivation factors. Conclusion. The Herzberg Motivation theory helped to identify suitable approaches to ensure that teaching topics, materials and assessment methods more closely reflected the health care needs of the community. Other medical schools undertaking a reform process may learn from this experience. © 2009 Hoat et al; licensee BioMed Central Ltd

    Nuclear structure of Au-181 studied via beta(+)/EC decay of Hg-181 at ISOLDE

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    The β+\beta ^+/EC decay of mass separated samples of 181^{181}Hg was studied employing the TATRA spectrometer at the ISOLDE facility at CERN. The decay scheme was constructed for the first time. A Broad Energy Germanium detector was used to achieve this by combination of high-gain γ\gamma -ray singles spectroscopy and γ\gamma –γ\gamma  coincidences. The systematics of excited states associated with the 1h11/2h_{11/2} proton-hole configuration in odd-Au isotopes was extended

    The spine in Paget’s disease

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    Paget’s disease (PD) is a chronic metabolically active bone disease, characterized by a disturbance in bone modelling and remodelling due to an increase in osteoblastic and osteoclastic activity. The vertebra is the second most commonly affected site. This article reviews the various spinal pathomechanisms and osseous dynamics involved in producing the varied imaging appearances and their clinical relevance. Advanced imaging of osseous, articular and bone marrow manifestations of PD in all the vertebral components are presented. Pagetic changes often result in clinical symptoms including back pain, spinal stenosis and neural dysfunction. Various pathological complications due to PD involvement result in these clinical symptoms. Recognition of the imaging manifestations of spinal PD and the potential complications that cause the clinical symptoms enables accurate assessment of patients prior to appropriate management

    Revisiting the pH-gated conformational switch on the activities of HisKA-family histidine kinases

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    Histidine is a versatile residue playing key roles in enzyme catalysis thanks to the chemistry of its imidazole group that can serve as nucleophile, general acid or base depending on its protonation state. In bacteria, signal transduction relies on two-component systems (TCS) which comprise a sensor histidine kinase (HK) containing a phosphorylatable catalytic His with phosphotransfer and phosphatase activities over an effector response regulator. Recently, a pH-gated model has been postulated to regulate the phosphatase activity of HisKA HKs based on the pH-dependent rotamer switch of the phosphorylatable His. Here, we have revisited this model from a structural and functional perspective on HK853-RR468 and EnvZ-OmpR TCS, the prototypical HisKA HKs. We have found that the rotamer of His is not influenced by the environmental pH, ruling out a pH-gated model and confirming that the chemistry of the His is responsible for the decrease in the phosphatase activity at acidic pH

    The SPEDE spectrometer

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    The electron spectrometer, SPEDE, has been developed and will be employed in conjunction with the Miniball spectrometer at the HIE-ISOLDE facility, CERN. SPEDE allows for direct measurement of internal conversion electrons emitted in-flight, without employing magnetic fields to transport or momentum filter the electrons. Together with the Miniball spectrometer, it enables simultaneous observation of Îł \gamma rays and conversion electrons in Coulomb excitation experiments using radioactive ion beams

    The formation of garnet in olivine-bearing metagabbros from the Adirondacks

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    A regional study of olivine-bearing metagabbros in the Adirondacks has permitted testing of the P(pressure)-T(temperature)-X(composition) dependence of garnet-forming reactions as well as providing additional regional metamorphic pressure data. Six phases, olivine, orthopyroxene, clinopyroxene, garnet, plagioclase and spinel, which can be related by the reactions: orthopyroxene+clinopyroxene+spinel +anorthite=garnet, and forsterite+anorthite=garnet occur together both in coronal and in equant textures indicative of equilibrium. Compositions of the respective minerals are typically Fo 25–72 , En 44–75 , En 30–44 Fs 9–23 Wo 47–49 , Pp 13–42 Alm 39–63 Gr 16–20 , An 29–49 and Sp 16–58 . When they occur in the same rock, equant and coronal garnets are homogeneous and compositionally identical suggesting that chemical equilibrium may have been attained despite coronal textures. Extrapolating reactions in the simple CMAS system to granulite temperatures and making thermodynamic corrections for solid solutions gives equilibration pressures (using the thermometry of Bohlen et al. 1980b) ranging from about 6.5 kb in the Lowlands and southern Adirondacks to 7.0–8.0 kb in the Highlands for the assemblage olivine-plagioclase-garnet. These results are consistent with inferred peak metamorphic conditions in the Adirondacks (Valley and Bohlen 1979; Bohlen and Boettcher 1981). Thus the isobaric retrograde path suggested by Whitney and McLelland (1973) and Whitney (1978) for the formation of coronal garnet in olivine metagabbros may not be required. Application of the same equilibria gives >8.7 kb for South Harris, Scotland and 0.9 kb for the Nain Complex. Disagreement of the latter value with orthopyroxeneolivine-quartz barometry (Bohlen and Boettcher 1981) suggests that the use of iron-rich rocks (olivines ≧Fa 50 ) results in errors in calculated pressures.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47335/1/410_2004_Article_BF00371301.pd
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