980 resultados para Compilation croisée


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The ground state thermal neutron cross section and the resonance integral for the (165)Ho(n, gamma)(166)Ho reaction in thermal and 1/E regions, respectively, of a thermal reactor neutron spectrum have been measured experimentally by activation technique. The reaction product, (166)Ho in the ground state, is gaining considerable importance as a therapeutic radionuclide and precisely measured data of the reaction are of significance from the fundamental point of view as well as for application. In this work, the spectrographically pure holmium oxide (Ho(2)O(3)) powder samples were irradiated with and without cadmium covers at the IEA-RI reactor (IPEN, Sao Paulo), Brazil. The deviation of the neutron spectrum shape from 1/E law was measured by co-irradiating Co, Zn, Zr and Au activation detectors with thermal and epithermal neutrons followed by regression and iterative procedures. The magnitudes of the discrepancies that can occur in measurements made with the ideal 1/E law considerations in the epithermal range were studied. The measured thermal neutron cross section at the Maxwellian averaged thermal energy of 0.0253 eV is 59.0 +/- 2.1 b and for the resonance integral 657 +/- 36b. The results are measured with good precision and indicated a consistency trend to resolve the discrepant status of the literature data. The results are compared with the values in main libraries such as ENDF/B-VII, JEF-2.2 and JENDL-3.2, and with other measurements in the literature.

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The (2)H(d,p)(3)H and (2)H(d,n)(3)He reactions have been indirectly studied by means of the Trojan Horse Method applied to the quasi-free (2)H((3)He, p(3)H)(1)H (2)H((3)He, n(3)He)(1)H reaction at 18 MeV of beam energy. This is the first experiment where the spectator (here (1)H) has been detected in coincidence with the charged participant, avoiding the limitations of standard neutron detectors. The d - d relative energy has been measured from 1.5 MeV down to 2 keV, at center of mass angles from 40A degrees to 170A degrees. Indirect angular distributions are compared with the direct behaviour in the overlapping regions.

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The bare nucleus S(E) factors for the (2)H(d, p)(3)H and (2)H(d.n)(3)He reactions have been measured for the first time via the Trojan Horse Method off the proton in (3)He from 1.5 MeV down to 2 key. This range overlaps with the relevant region for Standard Big Bang Nucleosynthesis as well as with the thermal energies of future fusion reactors and deuterium burning in the Pre-Main-Sequence phase of stellar evolution. This is the first pioneering experiment in quasi free regime where the charged spectator is detected. Both the energy dependence and the absolute value of the S(E) factors deviate by more than 15% from available direct data with new S(0) values of 57.4 +/- 1.8 MeVb for (3)H + p and 60.1 +/- 1.9 MeV b for (3)He + n. None of the existing fitting curves is able to provide the correct slope of the new data in the full range, thus calling for a revision of the theoretical description. This has consequences in the calculation of the reaction rates with more than a 25% increase at the temperatures of future fusion reactors. (C) 2011 Elsevier By. All rights reserved.

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Determinations of the volatile elements carbon, hydrogen, sulfur and nitrogen in many geological RM, performed with the LECO CHN and SC analysers, are presented. The method allowed the determination of S in concentrations from a few % m/m to 0.001% m/m or less, of C from % m/m to 0.01% m/m and of H from % m/m to 0.004% m/m. Accuracy was usually better than the XRF method (for S). All obtained values passed the Sutarno-Steger test, which establishes that vertical bar(mean(analysed) - mean(certified))vertical bar/ S(certified) < 2, for the cases with an appropriate number of determinations (n > 10 for each element). It was possible to perform routine determination of C, H and S with the instrumentation, coupled with the determination of major and minor elements in geological materials. Determination of nitrogen could also be performed on an exploratory basis, with improvements in the method dependent on the future availability of more reference materials with reliable composition of this element.

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We present electron-microprobe and single-crystal X-ray-diffraction data for a microlite-group mineral with a formula near NaCaTa(2)O(6)F from the Morro Redondo mine, Coronel Murta, Minas Gerais, Brazil. On the basis of these data, the formula is A(Na(0.88)Ca(0.88)Pb(0.02)square(0.22))(Sigma 2.00) (B)(Ta(1.70)Nb(0.14)Si(0.12)As(0.04))(Sigma 2.00) (X)[(O(5.75)(OH)(0.25)](Sigma 6.00) (Y)(F(0.73)square(0.27))(Sigma 1.00). According to the new nomenclature for the pyrochlore-supergroup minerals, it is intermediate between fluornatromicrolite and "" fluorcalciomicrolite"". The crystal structure, F (d3) over barm, a = 10.4396(12) angstrom, has been refined to an R(1) value of 0.0258 (wR(2) = 0.0715) for 107 reflections (MoK alpha radiation). There is a scarcity of crystal-chemical data for pyrochlore-supergroup minerals in the literature. A compilation of these data is presented here.

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The present study is focused on developing a nanoparticle carrier for the photosensitizer protoporphyrin IX for use in photodynamic therapy. The entrapment of protoporphyrin IX (Pp IX) in silica spheres was achieved by modification of Pp IX molecules with an organosilane reagent. The immobilized drug preserved its optical properties and the capacity to generate singlet oxygen, which was detected by a direct method from its characteristic phosphorescence decay curve at near-infrared and by a chemical method using 1,3-diphenylisobenzofuran to trap singlet oxygen. The lifetime of singlet oxygen when a suspension of Pp IX-loaded particles in acetonitrile was excited at 532 nm was determined as 52 mu s, which is in good agreement with the value determined for methylene blue in acetonitrile solution under the same conditions. The Pp IX-loaded silica particles have an efficiency of singlet oxygen generation (eta Delta) higher than the quantum yield of free porphyrins. This high efficiency of singlet oxygen generation was attributed to changes on the monomer-dimer equilibrium after photosentisizer immobilization.

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We have studied the spectroscopic properties of hair (white, blond, red, brown, and black) under illumination with visible light, giving special emphasis to the photoinduced generation of singlet oxygen ((1)O(2)). Irradiation of hair shafts (lambda(ex)>400 nm) changed their properties by degrading the melanin. Formation of C3 hydroperoxides in the melanin indol groups was proven by (1)H NMR. After 532-nm excitation, all hair shafts presented the characteristic (1)O(2) emission (lambda(em) = 1270 nm), whose intensity varied inversely with the melanin content. (1)O(2) lifetime was also shown to vary with hair type, being five times shorter in black hair than in blond hair, indicating the role of melanin as a (1)O(2) suppressor. Lifetime ranged from tenths of a nanosecond to a few microseconds, which is much shorter than the lifetime expected for (1)O(2) in the solvents in which the hair shafts were suspended, indicating that (1)O(2) is generated and suppressed inside the hair structure. Both eumelanin and pheomelanin were shown to produce and to suppress (1)O(2), with similar efficiencies. The higher amount of (1)O(2) generated in blond hair and its longer lifetime is compatible with the stronger damage that light exposure causes in blond hair. We propose a model to explain the formation and suppression of (1)O(2) in hair by photosensitization of melanin with visible light and the deleterious effects that an excess of visible light may cause in hair and skin. 2011 Published by Elsevier Inc.

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Development of an infrastructure for Brundtland Renewable Energy Network - BREN is a European Commission Alterner Project with Contract no XVII/4. 1030/Z96-032.The project has its origin in the UN-report “Our Common Future”, 1989. A change in and reduction of the use of energy was fundamental in order to reach the goals which the report proposed. Denmark decided on an action plan on how energy consumption could be reduced “Energi 2000 - Handlingsplan för en bäredygtig udvikling”. The ministries of energy in Denmark and Schleswig Holstein both agreed to start an energy saving project in a smaller town. The project was called “Brundtlandby” and the two first were Toftlund in South Jutland and Bredstedt in North Friesland. After a short period a further two German Cities, Rheinsberg and Viernheim, and Rajec in Slovakia joined the group. A network for the exchange of knowledge and experience between the cities was formed. The network, Brundtland City Project, inspired the participating cities in the continuing work with energy saving measures. The Brundtland City Project was presented at an international conference “Cities and Energy” in Trondheim, Norway,in December 1995. Great interest was shown in the project and it was decided that a network should be developed in northern European countries as a pilot project to be enlarged with other European countries later on. A steering committee was formed with representatives from the nordic countries.An application was sent to the European Commission, Alterner Program, and was approved in Juli 1996. The project was subdivided into nine activities. Activity 1, consisted of summarising the experiences of the Brundtland City Project in Toftlund, Denmark and the Brundtland Cities network in Slovakia, Germany and Denmark. The Scandinavian part started with Activity 2, to engage municipalities/cities in Finland, Norway and Sweden in the project. The Solar Energy Research Center, SERC, Högskolan Dalarna was appointed as co-ordinator for the Swedish part. The project was presented at a seminar on the 30th September for representatives from the municipalities of Borlänge and Falun. On the 10th of December 1996 the two municipalities accepted the invitation to join the Northern network. Pelle Helje, Borlänge Energi, has been informant for the municipality of Borlänge and Anders Goop, Department of Urban Planninginformant for the municipality of Falun with Jan Kaans, Estates department providing information to the basis for the Newsletter.Reports on the work in Borlänge and Falun municipalities have been made to Brundtland Center Denmark on three occasions; Activities 2-5, 16-12-1997, Activities 6-7, including parts of activities 8-9, 03-03-1998, and the basis for the Newsletter, 01-07-1998. The Nordic reports have been compiled at the Brundtland Center Denmark for submission to the European Commission. English has been the common language. After the report of activities 2 - 5 the participants wereinvited to a project meeting and a workshop at Brundtland Center the 23rd and 24th March 1998.This was the first occasion the participants in the project met and the network thus took a moreconcrete form. It also was decided that the next meeting should be in Borlänge in August 1998,with Borlänge Energi and Solar Energy Research Center SERC as organisers. As BrundtlandCentre Denmark was wound up for financial reasons, the project meeting in Borlänge wascancelled.Compilation of the Final Report was carried out by Esbensen Consultants in October 1998Future development of the networkIt is intended to continue the work with the Brundtland City Network as an “EU Thermie Bproject”and the network will be enlarged with the addition of four new Brundtland Cities from Austria, Germany, Italy and Great Britain. In addition the village of Putja in Estonia will join the network but this will be financed by the EU-Phare programme.

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De flesta har i sin närhet någon som drabbats av cancer och sjukdomsfallen har ökat genom åren. Den yrkesgrupp som ställer diagnos av denna sjukdom är patologer. Bristen på patologer är idagsläget stor och det finns därför ett behov av att finna effektiva lösningar för att möta denna brist och en ökande mängd patienter. För att digitalisera vävnadsproven som diagnostiseras, scannas dessa in med en glasscanner. Dessa digitala bildfiler kan sedan visas i ett bildvisningsprogram och delas digitalt mellan patologer på distans. Detta begrepp kallas för telepatologi. Studien utgår utifrån följande frågeställningar: Vilka krav är väsentliga och bör ingå i en utvärdering för bildvisningsprogram avsedda för diagnostik inom telepatologi? Vilket bildvisningsprogram är mest lämpat att implementeras i ett webbaserat system baserat på dessa väsentliga krav? Syftet med studien är att undersöka vilka krav som är väsentliga och bör ingå i en utvärdering av bildvisningsprogram avsedda för diagnostik inom telepatologi, samt att utföra en utvärdering av ett urval bildvisningsprogramvaror med hjälp av dessa krav. En fallstudie genomfördes med datainsamlingsmetoderna: intervjuer med två personer från studiens samarbetspartner CGM, Frågeformulär där Sveriges patologer var respondenter samt dokumentstudier för att samla in information gällande bildvisningsprogrammen. Studien tillämpar utvalda delar ur Anders G. Nilssons SIV-metod som tillvägagångsätt för att samla in krav samt för att göra ett urval av bildvisningsprogram som sedan utvärderas gentemot dessa krav. Resultaten av datainsamlingarna analyserades och ledde till ett kravdokument med väsentliga krav.Tre så kallade utslagsgivande faktorer bland dessa krav var att bildvisningsprogrammet måste vara webbaserat utan installation på klient, funktioner för in- och ut-zoomning samt panorering måste finnas. Utvärderingen av utvalda bildvisningsprogram visade slutligen att OpenSlide var mest lämpad att implementeras i ett webbaserat system.

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1. Urban ecosystems are expanding throughout the world, and urban ecology is attracting increasing research interest. Some authors have questioned the value of existing ecological theories for understanding the processes and consequences of urbanization.
2. In order to assess the applicability of metacommunity theory to urban systems, I evaluated three assumptions that underlie the theory – the effect of patch area, the effect of patch isolation, and species–environment relations – using data on assemblages of pond-breeding amphibians in the Greater Melbourne area of Australia. I also assessed the relative impact of habitat fragmentation, habitat isolation, and changes to habitat quality on these assemblages.
3. Poisson regression modelling provided support for an important increase in species richness with patch area (pond size) and a decrease in species richness with increasing patch isolation, as measured by surrounding road cover. Holding all other variables constant, species richness was predicted to be 2·8–5·5 times higher at the largest pond than at the smallest, while the most isolated pond was predicted to have 12–19% of the species richness of the least isolated pond. Thus, the data were consistent with the first two assumptions of metacommunity theory evaluated.
4. The quality of habitat at a pond was also important, with a predicted 44–56% decrease in the number of species detected at ponds with a surrounding vertical wall compared with those with a gently sloping bank. This demonstrates that environmental differences between habitat patches were also influencing amphibian assemblages, providing support for the species-sorting and/or mass-effect perspectives of metacommunity theory.
5. Without management intervention, urbanization may lead to a reduction in the number of amphibian species persisting in urban ponds, particularly where increasing isolation of ponds by roads and associated infrastructure reduces the probability of re-colonization following local extinction.

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1. With the aim of determining whether patterns of variation in macroinvertebrate assemblage composition across the hierarchy of spatial units in two lowland rivers changed during a supra-seasonal drought (1997–2000), patterns during a reduced flow season (1999–2000) were compared with those during two preceding higher flow seasons (1997–98 and 1998–99) using samples from the Glenelg and Wimmera Rivers, two lowland regulated rivers in western Victoria, Australia.

2. We hypothesised that (i) differences between reaches would increase during the reduced flow season owing to decreased hydrological connectivity, (ii) differences between the habitats would decrease because the cessation of flow in run habitats should cause them to become more similar to pool habitats and (iii) differences between microhabitats would also decrease because of reduced scour of inorganic substrata and large woody debris.

3. During each season, macroinvertebrates were sampled from three microhabitats (sand/silt substratum, large woody debris and macrophytes) that were hierarchically nested within a run or pool habitat and within one of three reaches within each river. A range of physico-chemical variables was also sampled.

4. Analysis of similarity showed that assemblage composition in both rivers during the higher flow seasons differed more among microhabitats than other spatial units. However, during the reduced flow season, assemblage composition in the Wimmera River differed most among reaches. This change in pattern was associated with the combined effects of decreased flow and longitudinal increases in salinity. In contrast, the fauna of the Glenelg River appeared to be resistant to the effects of the reduced flow season, owing to limited decline in water quality despite lower river discharge.

5. As salinisation and poor water quality in the Wimmera River result from human activities in the catchment, these results support the idea that human impacts on rivers can change macroinvertebrate scaling patterns and exacerbate the effects of drought beyond the tolerance of many riverine macroinvertebrates.

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Current scientific applications are often structured as workflows and rely on workflow systems to compile abstract experiment designs into enactable workflows that utilise the best available resources. The automation of this step and of the workflow enactment, hides the details of how results have been produced. Knowing how compilation and enactment occurred allows results to be reconnected with the experiment design. We investigate how provenance helps scientists to connect their results with the actual execution that took place, their original experiment and its inputs and parameters.

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Objective: Existing evidence suggests that family interventions can be effective in reducing relapse rates in schizophrenia and related conditions. Despite this, such interventions are not routinely delivered in Australian mental health services. The objective of the current study is to investigate the incremental cost-effectiveness ratios (ICERs) of introducing three types of family interventions, namely: behavioural family management (BFM); behavioural intervention for families (BIF); and multiple family groups (MFG) into current mental health services in Australia.

Method: The ICER of each of the family interventions is assessed from a health sector perspective, including the government, persons with schizophrenia and their families/carers using a standardized methodology. A two-stage approach is taken to the assessment of benefit. The first stage involves a quantitative analysis based on disability-adjusted life years (DALYs) averted. The second stage involves application of 'second filter' criteria (including equity, strength of evidence, feasibility and acceptability to stakeholders) to results. The robustness of results is tested using multivariate probabilistic sensitivity analysis.

Results: The most cost-effective intervention, in order of magnitude, is BIF (A$8000 per DALY averted), followed by MFG (A$21 000 per DALY averted) and lastly BFM (A$28 000 per DALY averted). The inclusion of time costs makes BFM more cost-effective than MFG. Variation of discount rate has no effect on conclusions.

Conclusions: All three interventions are considered 'value-for-money' within an Australian context. This conclusion needs to be tempered against the methodological challenge of converting clinical outcomes into a generic economic outcome measure (DALY). Issues surrounding the feasibility of routinely implementing such interventions need to be addressed.

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Information is given a privileged place in the psychiatric clinic, as illustrated by the prevalence and volume of data to be collected and forms to be completed by psychiatric nurses. Information though is different to knowledge. The present paper argues that information is part of a managerial discourse that implies commodification whereas knowledge is part of a clinical discourse that allows room for the suffering of the patient. Information belongs to the discourse of managerialism, one that positions the patient as customer/consumer and in doing so renders them unsuffering. The patient's suffering is silenced by their construction as a consumer. The discourse of managerialism seeks a complete data set of information. By way of contrast, another discourse, that of psychoanalysis offers the institution the idea that there are always holes, gaps, and uncertainty. The idea of uncertainty, gaps, things remaining unknown and a limit sits uncomfortably with the dominant discourse of managerialism; one that demands no limits, complete data sets, and many satisfied customers. This market model of managerialism denies the potential of the therapeutic relationship; that something curative might be produced via the transference. In addition, the managerialist discourse potentially positions the patient as both illegitimate and unsuffering.

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The aim of the study was to investigate the management of women with benign breast problems. A consecutive sample of women (n = 194) was assessed who presented to public or private sector providers. The main reasons for referral were breast lumps (62%); 56% of women who attended the public sector did not receive any recommendation compared to 40% who attended the private sector and clinical/general practitioner reviews were recommended to more women in the private sector (54%). Reasons for the discrepancy between public and private patients require further investigation. (Intern Med J 2005; 35: 357–358)