Borexino, a real-time device for low energy neutrino spectroscopy is nearing completion of construction in the underground laboratories at Gran Sasso, Italy (LNGS). The experiment's goal is the ...direct measurement of the flux of
7
Be solar neutrinos of all flavors via neutrino–electron scattering in an ultra-pure scintillation liquid. Seeded by a series of innovations which were brought to fruition by large-scale operation of a 4-ton test detector at LNGS, a new technology has been developed for Borexino. It enables sub-MeV solar neutrino spectroscopy for the first time. This paper describes the design of Borexino, the various facilities essential to its operation, its spectroscopic and background suppression capabilities and a prognosis of the impact of its results towards resolving the solar neutrino problem. Borexino will also address several other frontier questions in particle physics, astrophysics and geophysics.
Background. Primary care revival in Canada and elsewhere is viewed by many as conditional to the introduction of new organizational models. Endorsement by GPs is a key factor in the success of these ...models, and increasing GPs' job satisfaction is often one of the desired outcomes of the reforms currently underway. Objectives. The phenomenon of work satisfaction from the GP's perspective is not yet fully understood. The objectives of this study were to elicit its different facets and to understand better how organizational factors affect it. Methods. This is a case study carried out in the province of Quebec (Canada). We conducted semi-structured interviews with 28 GPs working in private clinics and community health centres (Centre local de services communautaires). Results. The main themes uncovered are related to the relationship between time management and quality of care, variation in work, autonomy in day-to-day practice, team ‘orientedness’ and social rewards. We also found that some GPs prefer to combine work in different organizations and models in order to increase their job satisfaction and to better cope with an increasingly complex task environment. Conclusion. Our study provides a comprehensive view of the various dimensions that GPs consider important in their professional life. Our findings suggest that, for many GPs, the perfect practice is tailor made and implies a combination of organizational models in order to fulfil their multiple professional goals. This has important implications for decision makers who are promoting new primary care models.
Tritium removal from TFTR Mueller, D.; Blanchard, W.; Collins, J. ...
Journal of nuclear materials,
01/1997, Volume:
241
Journal Article
Peer reviewed
Continued operation of the tokamak fusion test reactor (TFFR) with a mixture of deuterium and tritium fueling has permitted the opportunity to measure the retention of tritium in the graphite limiter ...and to investigate the use of discharge cleaning techniques and venting to remove the tritium. The tritium was introduced into TFTR by neutral beam injection and by gas puffing. The limiter is subject to erosion and codeposition. While short term retention was high, the retention averaged over the 1993–1995 D-T campaign was 52 ± 15%. The tritium removal techniques resulted in lowering the in-vessel inventory from 16.4 kCi (1
Ci = 2.076 × 10
19
tritium
atoms
and 10
kCi = 1.04
g) at the end of 1995 operation to 7.2 kCi at the start of the 1996 experimental program.
We evaluated the levels of p53, p21/waf1/cip1, hsp 27 and hsp 70 proteins in confluent cultures of human pancreatic tumor cell lines during the expression of inducible thermotolerance (IT). Two of ...these cell lines have wild type, whereas the other two have mutant, p53 status. Three cell lines expressed a significant amount of IT (
p<0.05 and better, one-tailed Student's
t-test); the fourth manifested little IT. Hsp 70 was upregulated in all cell lines. In contrast, hsp 27 was upregulated only in the cell lines that expressed IT. There was no correlation between either p53, or p21, protein levels and propensity to express IT. We conclude that hsp 27 is better associated with the expression of IT than hsp 70 in these cell lines.
Although it is regarded as a central concept in the practice of health promotion, intersectoral health-related action (IHA) has, to date, failed more often than it has succeeded. In this paper we ...review relevant social scientific literature, offer a working definition of intersectoral action and explore the usefulness of coalition theory as a theoretical framework through which to understand IHA theoretically and practically. Coalition theory has been previously used to study political alliances but it encompasses a series of parameters pertinent to the analysis of IHA. These parameters are: the rewards people expect to gain from participation in a coalition; the political assets they have to bring to the coalition; the non-utilitarian preferences they develop; the coalition's rules for decision-making; and the organisational context in which the coalition operates. We used these five parameters to study three intersectoral endeavours in Quebec, one at the local level and two at the provincial level, including activities associated with the Healthy Cities movement. Coalition theory proved useful in unravelling the mechanisms of these endeavours and appears promising as a tool for studying and/or implementing intersectoral health-related interventions.
Experiments were conducted on the packed-column air stripping of six volatile organic compounds found in groundwater migrating from a landfill site in Gloucester, Ont. Mass transfer rate constants ...determined experimentally, at column loading rates typical of full-scale application, were compared with rate constants predicted by three correlations. The model of Onda et al was found to give better predictions than the models of Sherwood and Holloway and Shulman et al. The model of Onda et al also gave reasonable predictions for saddles—a packing material for which the model had not been initially derived. Se condujeron experimentos en columnas cerradas de arrastre de aire de seis compuestos orgánicos volátiles encontrados en las aguas subterráneas contaminadas por un relleno de basura ubicado en Gloucester, Ont. Las constantes de transferencia de masa fueron determinadas experimentalmente, en columnas con tasas típicas de aplicaciones a gran escala y comparadas con las obtenidas mediante tres correlaciones. El modelo Onda fue encontrado que daba mejores predicciones que los modelos de Sherwood y Holloway y Shulman. El modelo Onda dio también razonables predicciones para otros materiales para los cuales el modelo no había sido inicialmente derivado.
The present study applies the approach described in Mark et al. for the testing of toxic chemicals produced during the drying of Douglas-fir. The genotoxic potential of Douglas-fir condensate has ...been previously unexplored and is thus an area of appropriate concern to the forest products industry, regulatory, agencies, and the general public. Previous research conducted in this laboratory has identified two wood-drying condensates that yield positive cytotoxic and genotoxic effects. The results of testing Southern yellow pine and Eastern white pine condensates have been reported elsewhere. Douglas-fir condensate, a third wood-drying condensate, was added in vitro in concentrations ranging from 0.1 to 100 microliters/ml to cultures of Chinese Hamster Ovary (CHO-WBL) cells. A dose response curve was observed with this condensate for both cytotoxicity and genotoxicity. The number of viable cells as well as the mitotic index (MI) and proliferative rate index (PRI) varied inversely with dosage. The result of chromosome aberration (Abs) analysis and sister chromatid exchange (SCE) analysis, both cytogenetic measures of genotoxicity, also gave statistically significant results.
Princeton Plasma Physics Laboratory, in collaboration with the Naval Research Laboratory, is currently investigating various novel materials (single-crystal silicon, 〈100〉, 〈110〉, and 〈111〉) for use ...as electron beam transmission windows in a krypton fluoride (KrF) excimer laser system. The primary function of the window is to isolate the active medium (excimer gas) from the excitation mechanism (field-emission diodes). The chosen window geometry must accommodate electron energy transfer >80% (750 keV) while maintaining the structural integrity during the mechanical load (1.3- to 2.0-atm base pressure differential, ~0.5-atm cyclic pressure amplitude, 5-Hz repetition rate) and the thermal load across the entire hibachi area (~0.9 W⋅cm
−2
). In addition, the window must be chemically resistant to attack by fluorine free radicals (hydrofluoric acid, secondary). In accordance with these structural, functional, and operational parameters, a 22.4-mm square silicon prototype window, coated with 500-nm thin-film silicon nitride (Si
3
N
4
), has been fabricated. The window consists of 81 square panes 0.019 ± 0.001 mm thick. The stiffened (orthogonal) sections are 0.065 mm wide and 0.500 mm thick (approximate). Assessment of silicon (and silicon nitride) material properties and computer-aided design modeling/analysis of the window design suggest that silicon may be a viable solution to inherent parameters and constraints.
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