The Significance of Business Exit for Future Entrepreneurial Activity

Purpose: The purpose of this paper is to analyse the impact of business exits on future dimensions of entrepreneurial activity at the macroeconomic level. Design/methodology/approach: This research uses the Global Entrepreneurship Monitor (GEM) data for 41 countries and the Generalized Method of Moments (GMM) to carry out the analysis. The paper differentiates the effect of the two components of total entrepreneurial activity, and the two motivations for it – opportunity and necessity entrepreneurship. Findings: The results presented here show a positive and significant effect of the coefficient associated with exits in all models. This means that the levels of entrepreneurial activity exceed business exits. The robustness of the models are tested, including other variables such as the fear of failure, the Gross Domestic Product, role models, entrepreneurial skills and the unemployment variables. The main hypothesis which stated that at national level business exits imply greater rates of opportunity-driven entrepreneurship is corroborated. Originality/value: One would expect that unemployment rates would imply higher levels of necessity entrepreneurship. However, results show that unemployment rates do in fact favour opportunity entrepreneurship levels. This could be due to those government policies that are aimed at promoting entrepreneurship through the capitalization of unemployment to be totally invested in a new start-up. To the best of our knowledge, this is the first panel data study to link previous exit rates to future dimensions of entrepreneurial activity. Keywords: Entrepreneurship, business exits, social values, industrial organization Paper type: Research paper

Task complexity, the Cognition Hypothesis and second language learning and performance

In this paper we describe a taxonomy of task demands which distinguishes between Task Complexity, Task Condition and Task Difficulty. We then describe three theoretical claims and predictions of the Cognition Hypothesis (Robinson 2001, 2003b, 2005a) concerning the effects of task complexity on: (a) language production; (b) interaction and uptake of information available in the input to tasks; and (c) individual differences-task interactions. Finally we summarize the findings of the empirical studies in this special issue which all address one or more of these predictions and point to some directions for continuing, future research into the effects of task complexity on learning and performance.

The spreading of the introduced seaweed Caulerpa taxifolia (Vahl) C. Agardh in the Mediterranean Sea: testing the boat transportation hypothesis

The Spreading of the Introduced Seaweed Caulerpa taxifolia (Vahl) C. Agardh in the Mediterranean Sea: Testing the Boat Transportation Hypothesis

Sex differences in brain plasticity: a new hypothesis for sex ratio bias in autism.

Several observations support the hypothesis that differences in synaptic and regional cerebral plasticity between the sexes account for the high ratio of males to females in autism. First, males are more susceptible than females to perturbations in genes involved in synaptic plasticity. Second, sex-related differences in non-autistic brain structure and function are observed in highly variable regions, namely, the heteromodal associative cortices, and overlap with structural particularities and enhanced activity of perceptual associative regions in autistic individuals. Finally, functional cortical reallocations following brain lesions in non-autistic adults (for example, traumatic brain injury, multiple sclerosis) are sex-dependent. Interactions between genetic sex and hormones may therefore result in higher synaptic and consecutively regional plasticity in perceptual brain areas in males than in females. The onset of autism may largely involve mutations altering synaptic plasticity that create a plastic reaction affecting the most variable and sexually dimorphic brain regions. The sex ratio bias in autism may arise because males have a lower threshold than females for the development of this plastic reaction following a genetic or environmental event.

More evidence concerning the aspect hypothesis: The acquisition of English progressive aspect by Catalan-Spanish instructed learners

A robust finding of studies investigating the Aspect Hypothesis is that learners at early stages of acquisition show a strong preference for using the progressive aspect as associated with activity verbs. As they advance in their acquisition of the second or foreign language, learners move from this prototypical association to associations traditionally considered to be more peripheral (e.g.-ing with accomplishments or achievements). Within this framework, the goal of this paper is to provide further evidence from groups of learners with different proficiency levels with regard to the acquisition of progressive aspect by tutored learners of English who are bilingual Catalan-Spanish. This is done by eliciting data by means of two different task types and by looking at both tokens and types. Our results are consistent with previous research according to which-ing morphology is closely associated with durative lexical aspect, although not necessarily with activity predicates. The study also shows that the type of task has an influence on the frequency and the distribution of learners" progressive forms.

Central serous chorioretinopathy: Recent findings and new physiopathology hypothesis.

Central serous chorioretinopathy (CSCR) is a major cause of vision threat among middle-aged male individuals. Multimodal imaging led to the description of a wide range of CSCR manifestations, and highlighted the contribution of the choroid and pigment epithelium in CSCR pathogenesis. However, the exact molecular mechanisms of CSCR have remained uncertain. The aim of this review is to recapitulate the clinical understanding of CSCR, with an emphasis on the most recent findings on epidemiology, risk factors, clinical and imaging diagnosis, and treatments options. It also gives an overview of the novel mineralocorticoid pathway hypothesis, from animal data to clinical evidences of the biological efficacy of oral mineralocorticoid antagonists in acute and chronic CSCR patients. In rodents, activation of the mineralocorticoid pathway in ocular cells either by intravitreous injection of its specific ligand, aldosterone, or by over-expression of the receptor specifically in the vascular endothelium, induced ocular phenotypes carrying many features of acute CSCR. Molecular mechanisms include expression of the calcium-dependent potassium channel (KCa2.3) in the endothelium of choroidal vessels, inducing subsequent vasodilation. Inappropriate or over-activation of the mineralocorticoid receptor in ocular cells and other tissues (such as brain, vessels) could link CSCR with the known co-morbidities observed in CSCR patients, including hypertension, coronary disease and psychological stress.

Local thermodynamics and the generalized Gibbs-Duhem equation in systems with long-range interactions

The local thermodynamics of a system with long-range interactions in d dimensions is studied using the mean-field approximation. Long-range interactions are introduced through pair interaction potentials that decay as a power law in the interparticle distance. We compute the local entropy, Helmholtz free energy, and grand potential per particle in the microcanonical, canonical, and grand canonical ensembles, respectively. From the local entropy per particle we obtain the local equation of state of the system by using the condition of local thermodynamic equilibrium. This local equation of state has the form of the ideal gas equation of state, but with the density depending on the potential characterizing long-range interactions. By volume integration of the relation between the different thermodynamic potentials at the local level, we find the corresponding equation satisfied by the potentials at the global level. It is shown that the potential energy enters as a thermodynamic variable that modifies the global thermodynamic potentials. As a result, we find a generalized Gibbs-Duhem equation that relates the potential energy to the temperature, pressure, and chemical potential. For the marginal case where the power of the decaying interaction potential is equal to the dimension of the space, the usual Gibbs-Duhem equation is recovered. As examples of the application of this equation, we consider spatially uniform interaction potentials and the self-gravitating gas. We also point out a close relationship with the thermodynamics of small systems.

Case management for emergency department frequent users : a randomized controlled trial

Background: Emergency department frequent users (EDFUs) account for a disproportionally high number of emergency department (ED) visits, contributing to overcrowding and high health-care costs. At the Lausanne University Hospital, EDFUs account for only 4.4% of ED patients, but 12.1% of all ED visits. Our study tested the hypothesis that an interdisciplinary case management intervention red. Methods: In this randomized controlled trial, we allocated adult EDFUs (5 or more visits in the previous 12 months) who visited the ED of the University Hospital of Lausanne, Switzerland between May 2012 and July 2013 either to an intervention (N=125) or a standard emergency care (N=125) group and monitored them for 12 months. Randomization was computer generated and concealed, and patients and research staff were blinded to the allocation. Participants in the intervention group, in addition to standard emergency care, received case management from an interdisciplinary team at baseline, and at 1, 3, and 5 months, in the hospital, in the ambulatory care setting, or at their homes. A generalized, linear, mixed-effects model for count data (Poisson distribution) was applied to compare participants' numbers of visits to the ED during the 12 months (Period 1, P1) preceding recruitment to the numbers of visits during the 12 months monitored (Period 2, P2).

Steroid hormones interrelationships in the metabolic syndrome: an introduction to the ponderostat hypothesis

Sexual dimorphism in the metabolic syndrome. The clairvoyant early implication of sex hormones in the characterization of the metabolic syndrome (MS) was detected early, and in accordance with the well-known sex-related main patterns of fat deposition in obesity: gynoid and android. The differences point to a direct implication of androgens and estrogens in the development, properties and maintenance of obesity and, by extension, to the cumulus of diseases grouped in the MS. For a long time, the key issue of the MS, i.e. the metabolic event explaining (and justifying) most of the derangements of the MS, has been considered to be insulin resistance (...)

Lipid mobilization and gluconeogenesis in plants: Do glyoxylate cycle enzyme activities constitute a real cycle? A hypothesis

Glyoxysomes are specialized peroxisomes present in various plant organs such as germinating cotyledons or senescing leaves. They are the site of beta-oxidation and of the glyoxylate cycle. These consecutive pathways are essential to the maintenance of gluconeogenesis initiated by the degradation of reserve or structural lipids. In contrast to mitochondrial beta-oxidation, which is prevalent in animal cells, glyoxysomal beta-oxidation and the glyoxylate cycle have no direct access to the mitochondrial respiratory chain because of the impermeability of the glyoxysomal membrane to the reduced cofactors. The necessity of NAD(+) regeneration can conceivably be fulfilled by membrane redox chains and/or by transmembrane shuttles. Experimental evidence based on the active metabolic roles of higher plant glyoxysomes and yeast peroxisomes suggests the coexistence of two mechanisms, namely a reductase/peroxidase membrane redox chain and a malate/aspartate shuttle susceptible to transfer electrons to the mitochondrial ATP generating system. Such a model interconnects beta-oxidation, the glyoxylate cycle, the respiratory chain and gluconeogenesis in such a way that glyoxysomal malate dehydrogenase is an essential and exclusive component of beta-oxidation (NAD(+) regeneration). Consequently, the classical view of the glyoxylate cycle is superseded by a tentative reactional scheme deprived of cyclic character.

Sidelobe elimination for generalized synthetic discriminant functions by a two-filter correlation and subsequent postprocessing of the intensity distributions

One of the most important problems in optical pattern recognition by correlation is the appearance of sidelobes in the correlation plane, which causes false alarms. We present a method that eliminate sidelobes of up to a given height if certain conditions are satisfied. The method can be applied to any generalized synthetic discriminant function filter and is capable of rejecting lateral peaks that are even higher than the central correlation. Satisfactory results were obtained in both computer simulations and optical implementation.

The induced generalized OWA operator

We present the induced generalized ordered weighted averaging (IGOWA) operator. It is a new aggregation operator that generalizes the OWA operator by using the main characteristics of two well known aggregation operators: the generalized OWA and the induced OWA operator. Then, this operator uses generalized means and order inducing variables in the reordering process. With this formulation, we get a wide range of aggregation operators that include all the particular cases of the IOWA and the GOWA operator, and a lot of other cases such as the induced ordered weighted geometric (IOWG) operator and the induced ordered weighted quadratic averaging (IOWQA) operator. We further generalize the IGOWA operator by using quasi-arithmetic means. The result is the Quasi-IOWA operator. Finally, we also develop a numerical example of the new approach in a financial decision making problem.