55 research outputs found
Utilization of mechanical engineering manpower in South Africa
No full textIncludes bibliographical references.The South African economy is currently experiencing a slow growth rate as a result of amongst other things, a shortage of engineers and technicians. This study sets out to investigate the present utilization and shortage of mechanical engineers. It was felt that with a comprehensive knowledge of the utilization of mechanical engineers, industrialists would be better equipped to improve productivity by taking the necessary steps to ensure effective utilization of engineering manpower. The study gathered empirical data, by means of a survey, from seven hundred and sixty seven (767) respondents located throughout South Africa. The study established that the present utilization of mechanical engineers is about sixty (60) percent and that the most probable cause of the poor utilization is a lack of sufficient technical support staff for the engineer
Screening for active and latent TB among migrants in France
No full textInternational audienceMigrants to Europe face a disproportionate burden of infections, including TB, yet little is known about the approach taken by primary and secondary care providers to screening and treatment. We therefore explored policy and practice relating to screening of active TB and latent TB infection (LTBI) in France. METHODS: We conducted an online national survey of French primary and secondary care physicians regarding their practices in relation to TB/LTBI screening among migrants. RESULTS: 367 physicians responded to the questionnaire among which 195 (53.1%) were primary care physicians, 126 (34.3%) were TB specialists in secondary care, and 46 (12.5%) other physicians; 303 (85.5%) were involved daily in the care of migrants. Most respondents recommended systematic TB screening with chest X-ray for migrants from medium and highincidence countries (71.9%). Primary care physicians were less likely to offer screening than physicians in other settings (aOR 0.21, 95% CI 0.09-0.48). 220 (61.8%) offered LTBI screening for children (<15 years) and 34.0% for all migrants from high incidence countries. CONCLUSION: Improving awareness on TB screening is a critical next step to improve health outcomes in migrant groups and meet regional targets for tackling TB
Search for a new gauge boson in π<sup>0</sup> decays
No full textA search was made for a new light gauge boson which might be produced in decay from neutral pions generated by 450-GeV protons in the CERN SPS neutrino target. Th e X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of conversion in the external Coulomb field of a nucleus.\ With protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data.\ This number is in agreement with the e xpectation of 18.12.8 background events from standard neutrino processes.\ A new 90 upper limit on the branching ratio (3.3~to~1.9) for masses ranging from 0 to 120 MeV/c is obtained.A search was made for a new light gauge boson which might be produced in decay from neutral pions generated by 450-GeV protons in the CERN SPS neutrino target. The X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of conversion in the external Coulomb field of a nucleus. With protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data. This number is in agreement with the expectation of 18.12.8 background events from standard neutrino processes. A new 90% C.L. upper limit on the branching ratio for masses ranging from 0 to 120 MeV/c^2 is obtained.A search was made for a new light gauge boson which might be produced in decay from neutral pions generated by 450-GeV protons in the CERN SPS neutrino target. The X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of conversion in the external Coulomb field of a nucleus. With protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data. This number is in agreement with the expectation of 18.12.8 background events from standard neutrino processes. A new 90% C.L. upper limit on the branching ratio for masses ranging from 0 to 120 MeV/c^2 is obtained.A search was made for a new light gauge boson X which might be produced in π 0 → γ + X decay from neutral pions generated by 450 GeV protons in the CERN SPS neutrino target. The X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of X → π 0 conversion in the external Coulomb field of a nucleus. With 1.45×10 18 protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data. This number is in agreement with the expectation of 18.1±2.8 background events from standard neutrino processes. A new 90 % C.L. upper limit on the branching ratio Br ( π 0 → γ + X )< (3.3 to 1.9)×10 −5 for X masses ranging from 0 to 120 MeV/ c 2 is obtained
Altitudinal gradients of tree species diversity and above-ground biomass on a small montane of Atlantic Central Africa
No full textTropical forests are both important carbon sinks and among the most biodiverse ecosystems on the earth. Patterns in aboveground biomass (AGB) and their relationship with species diversity of tropical forests over short altitudinal gradients are poorly known and the few previous studies on the subject have yielded variable results. Here, focusing on old-growth forests in Atlantic central Africa, we investigated how AGB varies with altitude, and how this variation is related to altitudinal changes in floristic composition and/or forest structure. We also investigate the relationship between AGB and species diversity along the altitudinal gradient. We inventoried all trees with a diameter (dbh) ≥ 10 cm in fifteen 1 ha permanent plots (100 m x 100 m) established along a transect from lowland (200 m) to submontane forests (900 m) in the Ngovayang Massif, southwestern Cameroon. Our data show a negative relationship between AGB and tree species richness, related to the elevation gradient. Forest AGB varied two-fold along this gradient, decreasing from 500-600 Mg ha-1 in lowland plots to less than 300 Mg ha-1 at the highest altitudes, while diversity increased, from 35.4 to 54.6 (Fisher's alpha index). The decreasing trend in AGB was mainly due to large trees (dbh ≥ 70 cm) whose contribution to AGB significantly decreased with altitude while the contribution from smaller trees was constant. Tree height and basal area also decreased significantly with increasing altitude, whereas stem density increased. While maximum potential tree height significantly decreased, wood specific gravity displayed no trend along the gradient. In particular, we showed that AGB variation was mainly determined by shift in species composition because large tree species were filtered out in the highest altitudes. Hence, our work further highlight the need for studying the drivers of large tree species distribution to better understand forest carbon stock variations in tropical forests. At the regional level, the Ngovayang massif was among the richest sites with highest level of biomass. Our results have strong implications in decisions on balancing carbon sequestration strategies with biodiversity conservation ones. Policy consequences are particularly relevant in forest management and land use planning.(Texte intégral
Measurement of the Lambda polarization in nu(mu) charged current interactions in the NOMAD experiment
No full textThe Lambda polarization in upsilon (mu) charged current interactions has been measured in the NOMAD experiment. The event sample (8087 reconstructed Lambda 's) is more than an order of magnitude larger than that of previous bubble chamber experiments, while the quality of event reconstruction is comparable. We observe negative polarization along the W-boson direction which is enhanced in the target fragmentation region: P-x(x(F) lt 0) = -0.21 +/- 0.04(stat) +/- 0.02(sys). In the current fragmentation region we find P-x(x(F) gt 0) = -0.09 +/- 0.06(stat) +/- 0.03(sys). These results provide a test of different models describing the nucleon spin composition and the spin transfer mechanisms. A significant transverse polarization tin the direction orthogonal to the Lambda production plane! has been observed for the first time in a neutrino experiment: P-y = -0.22 +/- 0.03(stat) +/- 0.01(sys). The dependence of the absolute value of P-y on the Lambda transverse momentum with respect to the hadronic jet direction is in qualitative agreement with the resuits from unpolarized hadron-hadron experiments
Final NOMAD results on ν<sub>μ</sub>→ν<sub>τ</sub> and ν<sub>e</sub>→ν<sub>τ</sub> oscillations including a new search for ν<sub>τ</sub> appearance using hadronic τ decays
No full textResults from the v, appearance search in a neutrino beam using the full NOMAD data sample are reported. A new analysis unifies all the hadronic tau decays, significantly improving the overall sensitivity of the experiment to oscillations. The "blind analysis" of all topologies yields no evidence for an oscillation signal. In the two-family oscillation scenario, this sets a 90% CL allowed region in the sin(2)2 theta (mu tau)-Deltam(2) plane which includes sin(2)2 theta (mu tau) lt 3.3 x 10(-4) at large Deltam(2) and Deltam(2) lt 0.7 eV(2)/c(4) at sin(2) 2 theta (mu tau) = 1. The corresponding contour in the nu (e) → nu (tau) oscillation hypothesis results in sin(2) 2 theta (l tau) lt 1.5 x 10(-2) at large Deltam(2) and Deltam(2) lt 5.9 eV(2)/c(4) at sin(2) 2 theta (l tau) = 1. We also derive limits on effective couplings of the tau lepton to nu (mu) or nu (l)
Intravenous Artesunate Reduces Parasite Clearance Time, Duration of Intensive Care, and Hospital Treatment in Patients with Severe Malaria in Europe: The TropNet Severe Malaria Study
No full text\ua9 The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.Intravenous artesunate improves survival in severe malaria, but clinical trial data from nonendemic countries are scarce. The TropNet severe malaria database was analyzed to compare outcomes of artesunate vs quinine treatment. Artesunate reduced parasite clearance time and duration of intensive care unit and hospital treatment in European patients with imported severe malaria
Longitudinal study based on a safety registry for malaria patients treated with artenimol-piperaquine in six European countries
No full textEuropean travellers to endemic countries are at risk of malaria and may be affected by a different range of co-morbidities than natives of endemic regions. The safety profile, especially cardiac issues, of artenimol (previously dihydroartemisinin)-piperaquine (APQ) Eurartesim® during treatment of uncomplicated imported falciparum malaria is not adequately described due to the lack of longitudinal studies in this population. The present study was conducted to partially fill this gap
Limit on νe→ντ oscillations from the NOMAD experiment
No full textIn the context of a two-flavour approximation we reinterpret the published NOMAD limit on nu(mu) --> nu(tau) oscillations in terms of nu(e) --> nu(tau) oscillations. At 90% C.L. we obtain sin2(2)theta(e tau) < 5.2 X 10(-2) for large Delta m(2), while for sin2(2)theta(e tau) = 1 the confidence region includes Delta m(2) < 11 eV(2)/c(4)
Assessment of early-modern observations of comets and supernovae: Focus on pre-telescopic European astrometric and physical data
No full textThe two-century period prior to the publication of Newton's Principia (first edition 1687; third edition 1726) was most important in terms of the radical changes that occurred in the observation, perception, and understanding of celestial objects that in turn spurred Newton to deduce his laws of gravitation and motion. Surprisingly, much of the available observational data embedded in contemporary texts from that two-century period has remained unused by modern astronomers, and this thesis (a) describes large amounts of data that were found and reanalyzed during the course of this Ph.D. research project, (b) places these data and their resulting analyses in context with the astronomy of the early-modern era, and (c) shows how modern astronomers and historians benefit from such information. The emphasis is placed here on west-European observations, as observations made elsewhere (eastern Europe, Asia) were isolated (not communicated for convenient rapid use by contemporary astronomers elsewhere) and did not develop or employ the level of precision that was utilized by western European astronomers through the extensive discussions that developed from correspondence and publication in Europe
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