Determinants of Underemployment During the Early Career: A Longitudinal Multi-country Study

This paper explores the relative effects of individual, organizational, labor market, and societal components on underemployment of young adults during their early career. Quantitative underemployment, defined as periods of unemployment, temporary employment, and part-time employment is of psychological importance, because it delays or hinders the integration of career starters into the world of work by excluding them from the experience needed to develop competencies and knowledge essential for functional participation in the labor force. A first step to decrease the occurrence of underemployment for career starters involves a better understanding of the relative importance of contributing factors. This paper used a longitudinal multi-country study to explore the relative weight of individual, organizational, and macro level factors on the occurrence of underemployment. From a sample of career starters in two occupational groups with relatively good employment prospects in six European countries, the results confirmed the relationships of underemployment to gender, education, initial experience, labor market outlook, and the socio-economic and socio-political situation of the country. The country specific variance in underemployment proved to be the most important predictor of youngsters later probability to be underemployed: its effect was about 2.5 times as large as the variance explained by the initial labor market experience and 10 times as large as the effect of the educational level

Work Meaning Patterns in Early Career

Work meaning patterns combine dimensions such as work centrality, expressive versus economic work goals, entitlement versus obligation societal norms into a holistic picture of the over time evolution of the meaning of work. Data from a longitudinal study in eight European countries are used to empirically establish major work meaning patterns and to study their stability during the early career. Further, some potential determinants of these work meaning patterns are analyzed and their consequences for the later career are considered. Statistical analyses include: cluster analysis, multiple discriminant analysis, analysis of covariance combined with multiple classification analysis, analysis of variance, and chi square analysis. Five cross-national work meaning patterns are identified for machine operators in their third year of labour market participation. One third of the sample remain in the same work meaning pattern over a time period of two years, while two third change their pattern membership. Respondents\u27 age, country, prior work environment, and their prior work socialization behaviours and outcomes have an impact on work meanings held two years later. In addition the work meaning pattern shared by the respondent allows to predict subsequent career enhancing strategies and effort expenditure at the job

The Impact of Early Career Experiences on Youth’s Proactive Work Socialization Behavior

Little is known about the impact of individual characteristics, historical factors, and situational characteristics on youth\u27s proactive work socialization behavior (career planning, skill development, consultation, and networking). Data from a longitudinal cross-national study (Belgium, England, Israel, Italy, the Netherlands and Spain) on career starters from two occupational groups, are used to test the hypothesized impact of predictor sets. Results confirm the positive impact of early career experience on the skill development proactive behavior; the dominant impact of the broader socioeconomic political and cultural country context on all four aspects of proactive behavior; and the sporadic effect of occupation, gender, and educational history on some proactive behavior dimensions

Initial Career and Work Meanings in Seven European Countries

The study explores the initial careers of two target groups of youngsters in seven European countries. Career patterns are constructed through cluster analysis on data gathered from the youngsters through a retrospective self-report procedure covering a period of 2;5 years. Six career patterns are identified across countries by the activities taking place (employment, various educational preparations, unemployment, military or civil service) and further described by personal and work-related variables as well as by work meanings and psychological well-being in the second year on the labor market. Some suggestions are given for further research and implications for career counseling, career education, organizational career guidance and development

Minisuperspaces: Observables and Quantization

A canonical transformation is performed on the phase space of a number of homogeneous cosmologies to simplify the form of the scalar (or, Hamiltonian) constraint. Using the new canonical coordinates, it is then easy to obtain explicit expressions of Dirac observables, i.e.\ phase space functions which commute weakly with the constraint. This, in turn, enables us to carry out a general quantization program to completion. We are also able to address the issue of time through ``deparametrization'' and discuss physical questions such as the fate of initial singularities in the quantum theory. We find that they persist in the quantum theory {\it inspite of the fact that the evolution is implemented by a 1-parameter family of unitary transformations}. Finally, certain of these models admit conditional symmetries which are explicit already prior to the canonical transformation. These can be used to pass to quantum theory following an independent avenue. The two quantum theories --based, respectively, on Dirac observables in the new canonical variables and conditional symmetries in the original ADM variables-- are compared and shown to be equivalent.Comment: 34 page

Lattice Boltzmann simulations of fluid flow in continental carbonate reservoir rocks and in upscaled rock models generated with multiple-point geostatistics

Microcomputed tomography (mu CT) and Lattice Boltzmann Method (LBM) simulations were applied to continental carbonates to quantify fluid flow. Fluid flow characteristics in these complex carbonates with multiscale pore networks are unique and the applied method allows studying their heterogeneity and anisotropy. 3D pore network models were introduced to single-phase flow simulations in Palabos, a software tool for particle-based modelling of classic computational fluid dynamics. In addition, permeability simulations were also performed on rock models generated with multiple-point geostatistics (MPS). This allowed assessing the applicability of MPS in upscaling high-resolution porosity patterns into large rock models that exceed the volume limitations of the mu CT. Porosity and tortuosity control fluid flow in these porous media. Micro-and mesopores influence flow properties at larger scales in continental carbonates. Upscaling with MPS is therefore necessary to overcome volume-resolution problems of CT scanning equipment. The presented LBM-MPS workflow is applicable to other lithologies, comprising different pore types, shapes, and pore networks altogether. The lack of straightforward porosity-permeability relationships in complex carbonates highlights the necessity for a 3D approach. 3D fluid flow studies provide the best understanding of flow through porous media, which is of crucial importance in reservoir modelling

Radio Emission and Particle Acceleration in SN 1993J

The radio light curves of SN 1993J are found to be well fit by a synchrotron spectrum, suppressed by external free-free absorption and synchrotron self-absorption. A standard r^-2 circumstellar medium is assumed, and found to be adequate. The magnetic field and number density of relativistic electrons behind the shock are determined. The strength of the magnetic field argues strongly for turbulent amplification behind the shock. The ratio of the magnetic and thermal energy density behind the shock is ~0.14. Synchrotron and Coulomb cooling dominate the losses of the electrons. The injected electron spectrum has a power law index -2.1, consistent with diffusive shock acceleration, and the number density scales with the thermal electron energy density. The total energy density of the relativistic electrons is, if extrapolated to gamma ~ 1, ~ 5x10^-4 of the thermal energy density. The free-free absorption required is consistent with previous calculations of the circumstellar temperature of SN 1993J, T_e ~ (2-10)x10^5 K. The relative importance of free-free absorption, Razin suppression, and the synchrotron self-absorption effect for other supernovae are briefly discussed. Guidelines for the modeling and interpretation of VLBI observations are given.Comment: accepted for Ap.

Detecting a Light Stop from Top Decays at the Tevatron

We study the possibility of discovering or excluding a light top squark (stop) based on top quark decays in the t-tbar events produced at the Fermilab Tevatron. In particular, we consider the Minimal Supersymmetric Standard Model with the sparticle spectrum m_{chi^+_1}+m_b, M_W+m_{chi^0_1}+m_b > m_{stop} > m_{chi^0_1}+m_c, where chi^0_1 is the lightest neutralino and chi^+_1 is the lightest chargino, so that t -> stop chi^0_1 and stop -> c chi^0_1. All other sparticle masses are assumed to be heavier than m_t. Such a spectrum seeks to explain the experimental values of alpha_s(M_Z^2), R_b and A_{LR} obtained from LEP/SLC data. We find that the prospect to observe a light stop via this channel at the Tevatron is very promising.Comment: 12 pages with 1 Postscript figure using psfig.sty. Postscript file available at http://sgi2.hep.anl.gov:8001/index.htm

Asymptotic silence of generic cosmological singularities

In this letter we investigate the nature of generic cosmological singularities using the framework developed by Uggla et al. We do so by studying the past asymptotic dynamics of general vacuum G2 cosmologies, models that are expected to capture the singular behavior of generic cosmologies with no symmetries at all. In particular, our results indicate that asymptotic silence holds, i.e., that particle horizons along all timelines shrink to zero for generic solutions. Moreover, we provide evidence that spatial derivatives become dynamically insignificant along generic timelines, and that the evolution into the past along such timelines is governed by an asymptotic dynamical system which is associated with an invariant set -- the silent boundary. We also identify an attracting subset on the silent boundary that organizes the oscillatory dynamics of generic timelines in the singular regime. In addition, we discuss the dynamics associated with recurring spike formation.Comment: 4 pages, 5 *.eps figures, RevTeX4; replaced by significantly revised version, to appear in Physical Review Letter

Acoustic properties in travertines and their relation to porosity and pore types

Sonic velocities of Pleistocene travertines were measured under variable confining pressures. Combined with petrographical characteristics and petrophysical data, i.e. porosity, permeability and density, it was determined that travertine porosity, pore types and cementation control compressional-wave (Vp) and shear-wave velocity (Vs). At 40 MPa confining pressures, Vp ranges between 3695 and 6097 m/s and Vs between 2037 and 3140 m/s. Velocity variations in travertines are, as with all carbonates, primarily linked to sample heterogeneity, i.e. differences in fabric, texture and porosity. They thus not necessarily emanate from changes in mineralogy or composition. Body wave velocities have a positive correlation with sample density and an inverse correlation with porosity. The travertines, sampled in extensional settings with normal faulting activity, define a specific compressional-wave velocity (y-axis) versus porosity (x-axis) equation, i.e. (log(y) = −0.0048x + 3.7844) that differs from the Vp-porosity paths defined by marine carbonates. Acoustic wave velocities are higher for travertines than for marine carbonates. Travertine precipitates form rigid rock frames, often called framestone, with large primary pores. Marine carbonates on the other hand often consist of (cemented) transported sediments, resulting in a rock frame that permits slower wave propagation when compared to the continental limestones.Acoustic velocity variations are linked to variations in pore types. Mouldic pores (macropores) show faster wave propagation than expected from their total porosities. Microporosity, interlaminar and interpeloidal porosity result in slower acoustic velocities. Framework pores and micro-moulds are associated with lowered acoustic velocities, while vug porosity is found above, on and below the general velocity-porosity trend. Not only the pore type, but also pore shapes exert control on body wave velocities. Cuboid-and rod-like pore shapes increase the velocity, while plate-and blade-like pore shapes have a negative effect on the velocity. The study demonstrates how seismic sections in travertine systems can contain seismic reflections that are not caused by non-carbonate intercalations, but relate to geobody boundaries, in which the seismic expression is function of porosity, pore types and shapes. This study provides and relates petrophysical data, i.e. porosity, permeability and acoustic velocities of travertines and is of importance for the interpretation of seismic reflection data in subsurface continental carbonate reservoirs