1,526 research outputs found
The demand for money by private firms in a regulated economy: Theoretical underpinnings and empirical evidence for Germany 1960 - 1998
Based on a cash-in-advance approach, this paper investigates theoretically the determinants of money holdings of firms under the conditions of a highly regulated labor market and analyses empirically the demand for money of German businesses during the period 1960-1998. As a result of our theoretical analysis the demand for cash balances by firms for shadow market activities depends among other things positively on the expected wage wedge. The empirical results show that the coefficient of the wage wegde has a positive sign in the long-run cointegrating relationship and is statistically significant positive in the short-run dynamics of the error correction model. -- Auf der Grundlage eines Cash-in-advance-Ansatzes untersucht der vorliegende Beitrag die Bestimmungsgründe der Geldnachfrage von deutschen Unternehmen (1960-1998) - vor dem Hintergrund eines hoch regulierten Arbeitsmarktes. Das theoretische Modell ergibt, daß Unternehmen Kasse für Aktivitäten auf dem Markt für Schwarzarbeit unterhalten und zwar um so mehr, je größer die Kluft zwischen den Bruttoarbeitskosten und den Nettolöhnen (wage wedge) ist. Der Koeffizient der wage wedge weist ein positives Vorzeichen in der Kointegrationsbeziehung auf und ist statistisch signifikant positiv in der kurzfristigen Dynamik des Fehler-Korrektur-Modells.Money Demand by Firms,Wage Wedge,Cash-in-Advance Model,Cointegration,Error-Correction,Geldnachfrage von Unternehmen,Cash-in-advance-Modell,Kointegration,FehlerKorrektur-Modell,Lohnzusatzkosten
The Excitation of Extended Red Emission: New Constraints on its Carrier From HST Observations of NGC 7023
The carrier of the dust-associated photoluminescence process causing the
extended red emission (ERE) in many dusty interstellar environments remains
unidentified. Several competing models are more or less able to match the
observed broad, unstructured ERE band. We now constrain the character of the
ERE carrier further by determining the wavelengths of the radiation that
initiates the ERE. Using the imaging capabilities of the Hubble Space
Telescope, we have resolved the width of narrow ERE filaments appearing on the
surfaces of externally illuminated molecular clouds in the bright reflection
nebula NGC 7023 and compared them with the depth of penetration of radiation of
known wavelengths into the same cloud surfaces. We identify photons with
wavelengths shortward of 118 nm as the source of ERE initiation, not to be
confused with ERE excitation, however. There are strong indications from the
well-studied ERE in the Red Rectangle nebula and in the high-|b| Galactic
cirrus that the photon flux with wavelengths shortward of 118 nm is too small
to actually excite the observed ERE, even with 100% quantum efficiency. We
conclude, therefore, that ERE excitation results from a two-step process. While
none of the previously proposed ERE models can match these new constraints, we
note that under interstellar conditions most polycyclic aromatic hydrocarbon
(PAH) molecules are ionized to the di-cation stage by photons with E > 10.5 eV
and that the electronic energy level structure of PAH di-cations is consistent
with fluorescence in the wavelength band of the ERE. Therefore, PAH di-cations
deserve further study as potential carriers of the ERE. (abridged)Comment: Accepted for Publication in the Ap
Spin relaxation of conduction electrons in bulk III-V semiconductors
Spin relaxation time of conduction electrons through the Elliot-Yafet,
D'yakonov-Perel and Bir-Aronov-Pikus mechanisms is calculated theoretically for
bulk GaAs, GaSb, InAs and InSb of both - and -type. Relative importance
of each spin relaxation mechanism is compared and the diagrams showing the
dominant mechanism are constructed as a function of temperature and impurity
concentrations. Our approach is based upon theoretical calculation of the
momentum relaxation rate and allows understanding of the interplay between
various factors affecting the spin relaxation over a broad range of temperature
and impurity concentration.Comment: an error in earlier version correcte
For richer or poorer in sickness for wealth: what price consumerism?
Affluence and material goods of varying types are portents of a millennium age consumer culture that encourages the masses to voluntarily participate in the need to buy, buy and buy! This trend to spend creates a purchasing fervour that preoccupies many consumers with the ongoing yearning to shop until they drop. Clever marketing tactics such as enticing smells, catchy jingles, prize-draw entries, lucrative sales, discounts and the recruitment of celebrities to advertise a range of different wares are just some of the ploys adopted by vendors and retailers to maintain the sustainability of this cycle of consumer spending. This scenario promotes what could be perceived as a never-ending desire to procure yet more products and merchandise, which can create social dilemmas such as personal debt due to, for example, impulse buying, excessive spending and unnecessary borrowing.
Retailers and manufacturers are driven by a quest to sell so constantly tout their goods to tempt consumers including those with a need for personal and social respect, to take the bait in order to encourage them to keep buying. This, coupled with the rapid advances in technology over recent decades, has made it easier for consumers to shop, order, obtain and pay for their goods from the comfort of an armchair or via handheld devices, and all at a tap of a button. In essence, technology has added to, or even exacerbated, the materialistic consumer trend as witnessed across many global societies today – from the east and the west to the north and the south. But what impact does consumerism have on the well-being of humankind and, in turn, the environment? This chapter adopts a comparative approach to answer this question by exploring the implications of consumerism as a means for broadening the topic’s framework and to contribute to debates regarding consumerism, well-being, social dilemma, sustainability and techno-economics
Polariton propagation in weak confinement quantum wells
Exciton-polariton propagation in a quantum well, under centre-of-mass
quantization, is computed by a variational self-consistent microscopic theory.
The Wannier exciton envelope functions basis set is given by the simple
analytical model of ref. [1], based on pure states of the centre-of-mass wave
vector, free from fitting parameters and "ad hoc" (the so called additional
boundary conditions-ABCs) assumptions. In the present paper, the former
analytical model is implemented in order to reproduce the centre-of-mass
quantization in a large range of quantum well thicknesses (5a_B < L < inf.).
The role of the dynamical transition layer at the well/barrier interfaces is
discussed at variance of the classical Pekar's dead-layer and ABCs. The Wannier
exciton eigenstates are computed, and compared with various theoretical models
with different degrees of accuracy. Exciton-polariton transmission spectra in
large quantum wells (L>> a_B) are computed and compared with experimental
results of Schneider et al.\cite{Schneider} in high quality GaAs samples. The
sound agreement between theory and experiment allows to unambiguously assign
the exciton-polariton dips of the transmission spectrum to the pure states of
the Wannier exciton center-of-mass quantization.Comment: 15 pages, 15 figures; will appear in Phys.Rev.
A participatory physical and psychosocial intervention for balancing the demands and resources among industrial workers (PIPPI): study protocol of a cluster-randomized controlled trial
Background: Need for recovery and work ability are strongly associated with high employee turnover, well-being and sickness absence. However, scientific knowledge on effective interventions to improve work ability and decrease need for recovery is scarce. Thus, the present study aims to describe the background, design and protocol of a cluster randomized controlled trial evaluating the effectiveness of an intervention to reduce need for recovery and improve work ability among industrial workers. Methods/Design: A two-year cluster randomized controlled design will be utilized, in which controls will also receive the intervention in year two. More than 400 workers from three companies in Denmark will be aimed to be cluster randomized into intervention and control groups with at least 200 workers (at least 9 work teams) in each group. An organizational resources audit and subsequent action planning workshop will be carried out to map the existing resources and act upon initiatives not functioning as intended. Workshops will be conducted to train leaders and health and safety representatives in supporting and facilitating the intervention activities. Group and individual level participatory visual mapping sessions will be carried out allowing team members to discuss current physical and psychosocial work demands and resources, and develop action plans to minimize strain and if possible, optimize the resources. At all levels, the intervention will be integrated into the existing organization of work schedules. An extensive process and effect evaluation on need for recovery and work ability will be carried out via questionnaires, observations, interviews and organizational data assessed at several time points throughout the intervention period. Discussion: This study primarily aims to develop, implement and evaluate an intervention based on the abovementioned features which may improve the work environment, available resources and health of industrial workers, and hence their need for recovery and work ability
Asexuality: Classification and characterization
This is a post-print version of the article. The official published version can be obtaineed at the link below.The term “asexual” has been defined in many different ways and asexuality has received very little research attention. In a small qualitative study (N = 4), individuals who self-identified as asexual were interviewed to help formulate hypotheses for a larger study. The second larger study was an online survey drawn from a convenience sample designed to better characterize asexuality and to test predictors of asexual identity. A convenience sample of 1,146 individuals (N = 41 self-identified asexual) completed online questionnaires assessing sexual history, sexual inhibition and excitation, sexual desire, and an open-response questionnaire concerning asexual identity. Asexuals reported significantly less desire for sex with a partner, lower sexual arousability, and lower sexual excitation but did not differ consistently from non-asexuals in their sexual inhibition scores or their desire to masturbate. Content analyses supported the idea that low sexual desire is the primary feature predicting asexual identity
Composição tecidual do peito e costelas fixas de caprinos do Alto Camaquã sacrificados aos 8 e 11 meses de idade.
Male reproductive health and environmental xenoestrogens
EHP is a publication of the U.S. government. Publication of EHP lies in the public domain and is therefore without copyright.
Research articles from EHP may be used freely; however, articles from the News section of EHP may contain photographs or figures copyrighted by other commercial organizations and individuals that may not be used without obtaining prior approval from both the EHP editors and the holder of the copyright.
Use of any materials published in EHP should be acknowledged (for example, "Reproduced with permission from Environmental Health Perspectives") and a reference provided for the article from which the material was reproduced.Male reproductive health has deteriorated in many countries during the last few decades. In the 1990s, declining semen quality has been reported from Belgium, Denmark, France, and Great Britain. The incidence of testicular cancer has increased during the same time incidences of hypospadias and cryptorchidism also appear to be increasing. Similar reproductive problems occur in many wildlife species. There are marked geographic differences in the prevalence of male reproductive disorders. While the reasons for these differences are currently unknown, both clinical and laboratory research suggest that the adverse changes may be inter-related and have a common origin in fetal life or childhood. Exposure of the male fetus to supranormal levels of estrogens, such as diethlylstilbestrol, can result in the above-mentioned reproductive defects. The growing number of reports demonstrating that common environmental contaminants and natural factors possess estrogenic activity presents the working hypothesis that the adverse trends in male reproductive health may be, at least in part, associated with exposure to estrogenic or other hormonally active (e.g., antiandrogenic) environmental chemicals during fetal and childhood development. An extensive research program is needed to understand the extent of the problem, its underlying etiology, and the development of a strategy for prevention and intervention.Supported by EU Contract BMH4-CT96-0314
- …