Job performance and job satisfaction: an integrated survey

The empirical evidence from the econometrics of self-reported job satisfaction and from organisational psychology on job performance confronts economic theory with some puzzling results. Job performance is found to be positively correlated with job satisfaction, whereas effort is assumed to be a disutility in the theory. Economic incentives are not found to be the main motivations of job performance; in some cases, indeed, they are even counterproductive. Interest in the job is found to account better for job satisfaction. This paper proposes an integrated approach to these issues by (i) conducting an interdisciplinary critical survey, (ii) proposing a simple economic framework within which to explain the puzzles. The key idea behind this framework is that intrinsic motivations and self-esteem help explain both job satisfaction and job performance. The employer can thus adopt other, more friendly actions, besides using incentives and controls to enhance performance by employees.job performance, job satisfaction, intrinsic motivations

Trophic habits of Muscardinus avellanarius (Mammalia Gliridae) as revealed by multiple stable isotope analysis

Multiple stable isotope analysis was used to investigate the diet of the common dormouse Muscardinus avellanarius in a mixed Mediterranean forest. δ13C and δ15N values of dormouse tissues compared to those of the vegetal and animal sources available in the area showed that the isotopic composition of both adult and juvenile M. avellanarius could be explained by a mixture of vegetal and animal organic matter. The isotopic composition of the assimilated nitrogen was mostly explained by the organic matter from flora. Among the vegetal components, flowers of Fagus silvatica, Quercus robur, and the rarer Crataegus oxyacantha, berries of Ilex aquifolium and acorns of Q. robur were found in the adult diet, while juveniles relied mainly on flowers of F. silvatica and acorns of Q. robur. Organic matter from eggs of passerines (Parus caeruleus and P. major) sharing nest-boxes affected the carbon isotopic signals in the assimilated fraction. The common dormouse in the mixed holly forests of the northern Sicily feeds primarily on the vegetal species which are abundant in its habitat. However, the diet of this small arboreal mammal cannot be fully characterised without considering the contribution of animal organic matter represented by bird eggs

Breeding abundance of threatened raptors as estimated from occurrence data

A model derived from the negative binomial distribution (NBD) has been proposed to solve the problem of predicting abundance of species from occurrence maps. The viability of NBD was explored for predicting the breeding abundance of five threatened species of raptor: Bonelli's Eagle Hieraaetus fasciatus, Golden Eagle Aquila chrysaetos, Peregrine Falco peregrinus, Lanner Falco biarmicus and Lesser Kestrel Falco naumanni. First, the accuracy of the NBD was tested in a reference area where the species abundance and occurrence were known through intensive field surveys. Next, an estimation of regional abundance derived from NBD was made for each species. These estimates were then compared to the existing regional data for the five raptors. The spatial distributions of the species were strongly aggregated, with F. peregrinus correctly showing the most widespread area of occupancy. The NBD gave a good approximation of the breeding abundance of the raptors, but tended to overestimate real data, particularly the regional data for falcons. Difficulties in species detection, insufficient sampling effort (F. biarmicus) or data collected over long time spans when population size increased (F. naumanni) may have reduced the NBD's resolution power. The ability of the method to predict local abundances over large areas from readily available presence-absence data, with relatively low fieldwork effort, could have considerable applications in conservation biology. © 2008 The Author

Incentives, job satisfaction and performance: empirical evidence in italian social enterprises

The paper offers a contribution to the understanding of the relations between incentives, satisfaction and performance of employees in social enterprises. It starts by criticizing the general hypotheses of the principal-agent theory and especially that employee satisfaction is determined exclusively by the level of salary received. These criticisms are explained both by looking to the organizational definition of job satisfaction by Locke and by taking a behavioural economics perspective. Job satisfaction is thus assumed to derive from a composed mix of incentives received on the job, equity perceived and employee motivations. It is no longer possible to assume that the wage is the sole (not even the most important) variable influencing worker performance. This claim is especially valid in social enterprises, where worker performance is difficult to monitor and evaluate, while high intrinsic motivations can better explain job satisfaction. The empirical analysis helps to shed light on the determinants of job satisfaction and individual performance. Data was collected on 4,134 employees working in 320 Italian social cooperatives. The paper introduces the methodologies of categorical principal components analysis, factor analysis, and Rasch models to group the items of intrinsic and extrinsic satisfaction, motivations and fairness. The data was then analysed by means of linear regression where the dependent variables are not only the stated degree of job satisfaction, but also satisfaction with extrinsic and intrinsic aspects of the job. The models come to demonstrate the particular relevance of employee motivations and fairness perceived in explaining job satisfaction and its sub-dimensions. Furthermore, organizational perceptions and the work environment are found to be significant as are individual perceptions and motivations.

MS, S and C Stars in the Infrared. Luminosities and Mass Loss Rates

In this note I present an outline of infrared (IR) photometric AGB properties, based on two samples of Galactic Long Period Variables (C- and S-type respectively). I show the various selection criteria used during the choice of the sources and describe the motivations of observing them at near- and mid-IR wavelengths. I discuss the problems encountered in estimating their luminosity and distance and motivate the methods I choose for this purpose. Properties of the luminosity functions and of the Hertzsprung-Russell (HR) diagrams obtained from the analysis are discussed. Finally, the choices made for estimating of the mass loss rates are described and preliminary results concerning them are shown.Comment: 10 pages, 6 figures, contribution from the IX Torino Workshop, to be published by AI

Theoretical Estimates of Stellar e-Captures. I. The half-life of 7Be in Evolved Stars

The Li enrichment in the Universe still presents various puzzles to astrophysics. One open issue is that of obtaining estimates for the rate of e-captures on 7Be, for T and rho conditions different from solar. This is important to model the Galactic nucleosynthesis of Li. In this framework, we present a new theoretical method for calculating the e-capture rate in conditions typical of evolved stars. We show how our approach compares with state-of-the-art techniques for solar conditions, where various estimates are available. Our computations include: i) "traditional" calculations of the electronic density at the nucleus, to which the e-capture rate for 7Be is proportional, for different theoretical approaches including the Thomas--Fermi, Poisson--Boltzmann and Debye--Hueckel (DH) models of screening, ii) a new computation, based on a formalism that goes beyond the previous ones, adopting a mean-field "adiabatic" approximation to the scattering process. The results obtained with our approach as well as with the traditional ones and their differences are discussed in some detail, starting from solar conditions, where our method and the DH model converge to the same solution. We then analyze the applicability of the various models to a rather broad range of T and rho values, embracing those typical of red giant stars. We find that, over a wide region of the parameter space explored, the DH approximation does not stand, and the more general method we suggest is preferable. We then briefly reanalyze the 7Li abundances in RGB and AGB stars of the Galactic Disk using the new Be-decay rate. We also underline that the different values of the electron density at the nucleus we find should induce effects on electron screening (for p-captures on Li itself, as well as for other nuclei) so that our new approach might have wide astrophysical consequences.Comment: Astrophts. Journal Feb. 1, 201

Habitat preferences of edible dormouse, Glis glis italicus: implications for the management of arboreal mammals in Mediterranean forests

Research on arboreal mammals living in Mediterranean forests is poor. Molecular research assessed the existence of an evolutionary significant unit in the edible dormouse populations living in south Italy, Sicily and Sardinia, and we decided to investigate the environmental factors capable of explaining its occurrence and abundance in Sicily, for a better management of these populations. We assessed the species habitat preferences by setting 25 large and 25 small nestboxes in five sample areas along an altitudinal gradient of the Madonie Range, and recorded habitat variables, food availability, and demographic data for two years. To obtain synthetic descriptors of the dormice habitat requirements, we extracted uncorrelated linear combinations of original variables by Principal Component Analysis; then we modelled habitat preferences of dormice by Generalized Linear Models, and selected the best models by Akaike’s information criterion and model averaging. Dormice abundances varied markedly between the two years of study. Population peaked and reproduced in 2010, a masting year of oaks and beeches. In the following non-masting year, a much lower number of adults and yearlings used nestboxes, without any sign of reproduction. In both years we found a significant effect of altitudinal vegetation belt. Dormice seem to prefer mixed broad-leaved and evergreen (cork, holm) oak forests below 800-1300 m a.s.l, to beech forests at higher altitude, and avoid coniferous plantations. Inside these woodlands they seem to prefer monotypic and mature oak-stands with dense canopies. Large nestboxes are more preferred than small ones only during reproductive years. Protection of large and mature woodland from wildfires and forestry management caring the retention of significant elements like old trees, logs and litter mounds are necessary to maintain the habitat of edible dormouse in Southern Mediterranean forests. Artificial nestboxes are a viable device to help population restocking in degraded forests

Dynamos and Chemical Mixing in Evolved Stars

In low-mass Red Giant Branch (RGB) and Asymptotic Giant Branch (AGB) stars, anomalous mixing must transport material near the hydrogen-burning shell to the convective envelope. Recently, it was suggested that buoyant magnetic flux tubes could supply the necessary transport rate (Busso et al. 2007). The fields are assumed to originate from a dynamo operating in the stellar interior. Here, we show what is required of an $\alpha-\Omega$ dynamo in the envelope of an AGB star to maintain these fields. Differential rotation and rotation drain via turbulent dissipation and Poynting flux, so if shear can be resupplied by convection, then large-scale toroidal field strengths of \left\simeq3\times10^4 G can be sustained at the base of the convection zone.Comment: 7 pages, 3 figures. To appear in AIP Proceedings of the IXth Torino Workshop on AGB Nucleosynthesi