2,232 research outputs found
Communication satisfaction, job satisfaction, organisational commitment and intention to leave
The retention of highly motivated, skilled and committed employees is a major concern by organisations to achieve a competitive advantage. The turnover intentions of human capital are of interest to managers, employees, and organisations today. This study explores a theoretical model of turnover intentions that included three proximal variables, job satisfaction, affective and continuance commitment, the distal variables of subordinate communication, horizontal communication, personal feedback, media quality, communication climate, supervisor communication, job-related communication, and management communication, with turnover intentions. A questionnaire was completed by 101 participants of a rental firm in New Zealand. Job satisfaction, affective commitment, continuance commitment, subordinate communication, horizontal communication, personal feedback, media quality, communication climate, supervisor communication, job-related communication, and management communication correlated with turnover intentions. The results of the mediated regression analysis indicated that job satisfaction, affective commitment, and continuance commitment are significant mediators between the eight distal (organisational communication) variables, with turnover intentions.
This study highlights the necessity for managers to develop good quality relationships with their employees to improve the quality of their communication, to foster job satisfaction, affective commitment, and continuance commitment to reduce turnover intentions. The conclusion of this study discusses the practical implications for managers, and organisations and the direction for future research
The ELODIE and SOPHIE Search for Northern Extrasolar Planets: Jupiter-Analogs around Sun-Like Stars
We present radial-velocity measurements (RV) obtained in one of the numbers of programs underway to search for extrasolar planets with the spectrograph SOPHIE at the 1.93-m telescope of the Observatoire de Haute-Provence. Targets were selected from catalogs observed with ELODIE, which had been mounted previously at the telescope, in order to detect long-period planets with an extended database close to 15 year
The HARPS search for southern extra-solar planets XXXV. Planetary systems and stellar activity of the M dwarfs GJ 3293, GJ 3341, and GJ 3543
Context. Planetary companions of a fixed mass induce larger amplitude reflex
motions around lower-mass stars, which helps make M dwarfs excellent targets
for extra-solar planet searches. State of the art velocimeters with 1m/s
stability can detect very low-mass planets out to the habitable zone of these
stars. Low-mass, small, planets are abundant around M dwarfs, and most known
potentially habitable planets orbit one of these cool stars.
Aims. Our M-dwarf radial velocity monitoring with HARPS on the ESO 3.6m
telescope at La Silla observatory makes a major contribution to this sample.
Methods. We present here dense radial velocity (RV) time series for three M
dwarfs observed over years: GJ 3293 (0.42M), GJ 3341
(0.47M), and GJ 3543 (0.45M). We extract those RVs through
minimum matching of each spectrum against a high S/N ratio stack of
all observed spectra for the same star. We then vet potential orbital signals
against several stellar activity indicators, to disentangle the Keplerian
variations induced by planets from the spurious signals which result from
rotational modulation of stellar surface inhomogeneities and from activity
cycles.
Results. Two Neptune-mass planets - and
- orbit GJ 3293 with periods d and
d, possibly together with a super-Earth -
- with period . A super-Earth
- - orbits GJ 3341 with . The RV
variations of GJ 3543, on the other hand, reflect its stellar activity rather
than planetary signals.Comment: Accepted for publication in A&A, 19 pages, 12 figures, 7 table
Development and characterization of a single particle laser ablation mass spectrometer (SPLAM) for organic aerosol studies
A single particle instrument was developed for real-time analysis of organic aerosol. This instrument, named Single Particle Laser Ablation Mass Spectrometry (SPLAM), samples particles using an aerodynamic lens system for which the theoretical performances were calculated. At the outlet of this system, particle detection and sizing are realized by using two continuous diode lasers operating at &lambda; = 403 nm. Polystyrene Latex (PSL), sodium chloride (NaCl) and dioctylphtalate (DOP) particles were used to characterize and calibrate optical detection of SPLAM. The optical detection limit (DL) and detection efficiency (DE) were determined using size-selected DOP particles. The DE ranges from 0.1 to 90% for 100 and 350 nm DOP particles respectively and the SPLAM instrument is able to detect and size-resolve particles as small as 110–120 nm. During optical detection, particle scattered light from the two diode lasers, is detected by two photomultipliers and the detected signals are used to trigger UV excimer laser (&lambda; = 248 nm) used for one-step laser desorption ionization (LDI) of individual aerosol particles. The formed ions are analyzed by a 1 m linear time-of-flight mass spectrometer in order to access to the chemical composition of individual particles. The TOF-MS detection limit for gaseous aromatic compounds was determined to be 0.85 × 10<sup>&minus;15</sup> kg (&sim;4 × 10<sup>3</sup> molecules). DOP particles were also used to test the overall operation of the instrument. The analysis of a secondary organic aerosol, formed in a smog chamber by the ozonolysis of indene, is presented as a first application of the instrument. Single particle mass spectra were obtained with an effective hit rate of 8%. Some of these mass spectra were found to be very different from one particle to another possibly reflecting chemical differences within the investigated indene SOA particles. Our study shows that an exhaustive statistical analysis, over hundreds of particles, and adapted reference mass spectra are further needed to understand the chemical meaning of single particle mass spectra of chemically complex submicrometer-sized organic aerosols
Seasonal modulation of seismicity in the Himalaya of Nepal
International audience[1] For the period 1995 –2000, the Nepal seismic network recorded 37 ± 8% fewer earthquakes in the summer than in the winter; for local magnitudes ML > 2 to ML > 4 the percentage increases from 31% to 63% respectively. We show the probability of observing this by chance is less than 1%. We find that most surface loading phenomena are either too small, or have the wrong polarity to enhance winter seismicity. We consider enhanced Coulomb failure caused by a pore-pressure increase at seismogenic depths as a possible mechanism. For this to enhance winter seismicity, however, we find that fluid diffusion following surface hydraulic loading would need to be associated with a six-month phase lag, which we consider to be possible, though unlikely. We favor instead the suppression of summer seismicity caused by stress-loading accompanying monsoon rains in the Ganges and northern India, a mechanism that is discussed in a companion article
Characterization of the hot Neptune GJ 436b with Spitzer and ground-based observations
We present Spitzer Space Telescope infrared photometry of a secondary eclipse
of the hot Neptune GJ436b. The observations were obtained using the 8-micron
band of the InfraRed Array Camera (IRAC). The data spanning the predicted time
of secondary eclipse show a clear flux decrement with the expected shape and
duration. The observed eclipse depth of 0.58 mmag allows us to estimate a
blackbody brightness temperature of T_p = 717 +- 35 K at 8 microns. We compare
this infrared flux measurement to a model of the planetary thermal emission,
and show that this model reproduces properly the observed flux decrement. The
timing of the secondary eclipse confirms the non-zero orbital eccentricity of
the planet, while also increasing its precision (e = 0.14 +- 0.01). Additional
new spectroscopic and photometric observations allow us to estimate the
rotational period of the star and to assess the potential presence of another
planet.Comment: Accepted for publication in A&A on 11/09/2007; 7 pages, 6 figure
Influence of the calcaneus shape on the risk of posterior heel ulcer using 3D patient-specific biomechanical modeling.
International audienceMost posterior heel ulcers are the consequence of inactivity and prolonged time lying down on the back. They appear when pressures applied on the heel create high internal strains and the soft tissues are compressed by the calcaneus. It is therefore important to monitor those strains to prevent heel pressure ulcers. Using a biomechanical lower leg model, we propose to estimate the influence of the patient-specific calcaneus shape on the strains within the foot and to determine if the risk of pressure ulceration is related to the variability of this shape. The biomechanical model is discretized using a 3D Finite Element mesh representing the soft tissues, separated into four domains implementing Neo Hookean materials with different elasticities: skin, fat, Achilles' tendon, and muscles. Bones are modelled as rigid bodies attached to the tissues. Simulations show that the shape of the calcaneus has an influence on the formation of pressure ulcers with a mean variation of the maximum strain over 6.0 percentage points over 18 distinct morphologies. Furthermore, the models confirm the influence of the cushion on which the leg is resting: a softer cushion leading to lower strains, it has less chances of creating a pressure ulcer. The methodology used for patient-specific strain estimation could be used for the prevention of heel ulcer when coupled with a pressure sensor
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