2,759 research outputs found
Job satisfaction and life satisfaction: Analysis of a reciprocal model with social demographic moderators
The general objective of the study was to empirically test a reciprocal model of job satisfaction and life satisfaction while controlling for some social demographic variables. 827 employees working in 34 car dealerships in Northern Quebec (56% responses rate) were surveyed. The multiple item questionnaires were analysed using correlation analysis, chi square and ANOVAs. Results show interesting patterns emerging for the relationships between job and life satisfaction of which 49.2% of all individuals have spillover, 43.5% compensation, and 7.3% segmentation type of relationships. Results, nonetheless, are far richer and the model becomes much more refined when social demographic indicators are taken into account. Globally, social demographic variables demonstrate some effects on each satisfaction individually but also on the interrelation (nature of the relations) between life and work satisfaction.Job satisfaction, life satisfaction, spillover-compensation-segmentation model
Modification of nuclear transitions in stellar plasma by electronic processes: K-isomers in 176Lu and 180Ta under s-process conditions
The influence of the stellar plasma on the production and destruction of
K-isomers is studied for the examples 176Lu and 180Ta. Individual
electromagnetic transitions are enhanced predominantly by nuclear excitation by
electron capture, whereas the other mechanisms of electron scattering and
nuclear excitation by electron transition give only minor contributions. It is
found that individual transitions can be enhanced significantly for low
transition energies below 100 keV. Transitions with higher energies above 200
keV are practically not affected. Although one low-energy transition in 180Ta
is enhanced by up to a factor of 10, the stellar transition rates from low-K to
high-K states via so-called intermediate states in 176Lu and 180Ta do not
change significantly under s-process conditions. The s-process nucleosynthesis
of 176Lu and 180Ta remains essentially unchanged.Comment: 10 pages, 10 figures, Phys. Rev. C, accepte
Directed transport in a classical lattice with a high-frequency driving
We analyze the dynamics of a classical particle in a spatially periodic
potential under the influence of a periodic in time uniform force. It was shown
in [S.Flach, O.Yevtushenko, Y. Zolotaryuk, Phys. Rev. Lett. 84, 2358 (2000)]
that despite zero average force, directed transport is possible in the system.
Asymptotic description of this phenomenon for the case of slow driving was
developed in [X. Leoncini, A. Neishtadt, A. Vasiliev, Phys. Rev. E 79, 026213
(2009)]. Here we consider the case of fast driving using canonical perturbation
theory. An asymptotic formula is derived for the average drift velocity as a
function of the system parameters and the driving law. We show that directed
transport arises in an effective Hamiltonian that does not possess chaotic
dynamics, thereby clarifying the relation between chaos and transport in the
system. Sufficient conditions for transport are derived.Comment: 5 page
Characterisation of the transmissivity field of a fractured and karstic aquifer, Southern France
International audienceGeological and hydrological data collected at the Terrieu experimental site north of Montpellier, in a confined carbonate aquifer indicates that both fracture clusters and a major bedding plane form the main flow paths of this highly heterogeneous karst aquifer. However, characterising the geometry and spatial location of the main flow channels and estimating their flow properties remain difficult. These challenges can be addressed by solving an inverse problem using the available hydraulic head data recorded during a set of interference pumping tests.We first constructed a 2D equivalent porous medium model to represent the test site domain and then employed regular zoning parameterisation, on which the inverse modelling was performed. Because we aim to resolve the fine-scale characteristics of the transmissivity field, the problem undertaken is essentially a large-scale inverse model, i.e. the dimension of the unknown parameters is high. In order to deal with the high computational demands in such a large-scale inverse problem, a gradient-based, non-linear algorithm (SNOPT) was used to estimate the transmissivity field on the experimental site scale through the inversion of steady-state, hydraulic head measurements recorded at 22 boreholes during 8 sequential cross-hole pumping tests. We used the data from outcrops, borehole fracture measurements and interpretations of inter-well connectivities from interference test responses as initial models to trigger the inversion. Constraints for hydraulic conductivities, based on analytical interpretations of pumping tests, were also added to the inversion models. In addition, the efficiency of the adopted inverse algorithm enables us to increase dramatically the number of unknown parameters to investigate the influence of elementary discretisation on the reconstruction of the transmissivity fields in both synthetic and field studies.By following the above approach, transmissivity fields that produce similar hydrodynamic behaviours to the real head measurements were obtained. The inverted transmissivity fields show complex, spatial heterogeneities with highly conductive channels embedded in a low transmissivity matrix region. The spatial trend of the main flow channels is in a good agreement with that of the main fracture sets mapped on outcrops in the vicinity of the Terrieu site suggesting that the hydraulic anisotropy is consistent with the structural anisotropy. These results from the inverse modelling enable the main flow paths to be located and their hydrodynamic properties to be estimated
Kinematic design of a finger abduction mechanism for an anthropomorphic robotic hand
This paper presents the kinematic design of an abduction mechanism for the fingers of an underactuated anthropomorphic robotic hand. This mechanism will enhance the range of feasible grasps of the underactuated hand without significantly increasing its complexity. The analysis of the link between the index finger and the third finger is first assessed, where the parameters are studied in order to follow the amplitude constraint and to minimize the coordination error. Then, the study of the mechanism joining the third finger and the little finger is summarized. Finally, a prototype of the finger's abduction system is presented. <br><br> <i>This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010), 19 August 2010, Montréal, Canada.</i>
Degradation of cassava linamarin by lactic acid bacteria
Six out of ten lactic acid bacteria strains tested displayed linamarase activity. #Lactobacillus plantarum$ strain A6 displayed the greatest activity affecting 36 U/g cells on MRS cellobiose. The strain also broke down in less than 2 hours the linamarin extracted from cassava juice. HPLC analysis of the products of the reaction showed that the bacteria converted the linamarin into lactic acid and acetone cyanohydrin. (Résumé d'auteur
HIP FLEXORS RESISTENCE IN YOUTH HOCKEY PLAYERS
BACKGROUND AND OBJECTIVE. In today’s youth hockey leagues, the participation of an individual is based on the chronologic age without regard to the children's variations in development and maturity. Although it is currently accepted that the overall strength and growth of children increases linearly throughout childhood until puberty, the individual body parts growth do not develop at the same rate. The object of this project was to evaluate pelvic girdle resistance of youth hockey players in relation to leg length. METHOD. Nine hundred (n=900) hockey players aged 6 to 16 participated in the study. First, a 14 points physical examination was done on all subjects. Finally the Milgram test (modified bilateral leg raise) was performed. This procedure represents a good and easily performed test of hip flexors resistance and permits possible detection of thecal pathology. Incidence of positive Milgram test is presented and a Chi square statistical test is used. RESULTS. The results indicate that in our subjects, the youngest and oldest players had the lowest percentage of positive findings on the Milgram test; 6 years old: 5%, 16 years old 7.14%. The 10, 11 and 12 year old groups had a mean value of 47.22% positive Milgram tests. From all the 257 subjects with positive Milgram test only 2 individuals demonstrated possible thecal pathologies after the fourteen steps examination was performed. The Chisquare (x*) statistical test indicates that the difference between the observed frequency and between the theoretical frequency is significant (X2 = 117,081, df = 10, Q < .OOl). CONCLUSIONS. It appears from this study that almost 50% of children in the 10, 11 and 12 year old have difficulty in performing a simple hip flexing resistance exercise. This situation may be secondary to an uneven rate of growth of the lower limbs versus torso, therefore increasing the leg moment arms, thus increasing load and brending moments on the pelvic structures. . These results may explain the observed difficulty some of these hockey players experience in performing specific skills demanding high pelvic and hip flexors strength and resistance. Researchers are encourage to pursue biomechanical investigation f limb length ratio and their specific effects on axial structures and development
Élaboration de normes DRIS provisoires pour des transplants de céleri
Nous avons utilisé une banque de données contenant 215 observations pour obtenir des normes DRIS (Diagnosis and Recommandation Integrated System) provisoires pour des transplants de céleri (Apium graveolens var. Dulce). La détermination des normes s'est faite en considérant un groupe de tête au rendement supérieur ou égal à 1600 g/plant (27 % de la population). Sur 45 rapports nutritionnels mesurés dans la partie aérienne des transplants, 26 ont présenté des rapports de variance permettant de distinguer significativement le groupe produisant des rendements supérieurs. Le coefficient de corrélation entre l'indice de déséquilibre nutritionnel (IDN) et les rendements s'est révélé très significatif. Les normes provisoires ont été confrontées à un ensemble indépendant de données obtenues chez des producteurs de la région du sud de Montréal (Québec). Les IDN calculés sur ces plantes échantillonnées au stade implantation (environ 27 jours après la plantation) ont été significativement corrélés aux rendements, malgré le fait que le tissu échantillonné et le stade de croissance aient été relativement éloignés de ceux correspondant aux normes. Les normes ont permis d'identifier la cause probable d'un problème de croissance induit par l'utilisation d'une solution fertilisante ne convenant pas à la production de transplants.A data bank of 215 observations was used to elaborate preliminary DRIS norms for celery (Apium graveolens var.Dulce) transplants. The threshold yield for high yielders was set at 1600 g/plant (27% of the population). Of the 45 nutrient ratios obtained, 26 presented significant variance ratios between low and high yielders. The correlation coefficient between nutrient imbalance index (Nil) and yield was highly significant. The norms were tested on an independent set of data obtained from celery growers located south of Montreal (Quebec). The Nil obtained from plants at the implantation stage (about 27 days after transplanting) was significantly correlated to yield even if the sampled tissue was different from that used for norm calculations. The norms were also used to identify the likely cause of a growth problem induced by a nutrient solution not suited for transplant production
Semiclassical quantization of electrons in magnetic fields: the generalized Peierls substitution
A generalized Peierls substitution which takes into account a Berry phase
term must be considered for the semiclassical treatment of electrons in a
magnetic field. This substitution turns out to be an essential element for the
correct determination of the semiclassical equations of motion as well as for
the semiclassical Bohr-Sommerfeld quantization condition for energy levels. A
general expression for the cross-sectional area is derived and used as an
illustration for the calculation of the energy levels of Bloch and Dirac
electrons
Prevalence of multidrug resistance in Escherichia coli in the immediate calves' environment in Swiss dairy farms
In dairy farms, calves are the animal group that carries the fecal flora with the
highest prevalence of antimicrobial resistance (AMR). Calves' age and
antimicrobial exposure are major factors affecting AMR prevalence. The calves'
housing environment is suspected to be a reservoir of resistant bacteria, acting
as a source of colonization of the calves' gut and maintenance of AMR in farms.
Aims
To describe the prevalence of AMR and multidrug resistance (MDR) in
Escherichia coli isolated from preweaned calves' housing environment in Swiss
dairy farms
To explore factors associated with AMR and MD
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