846 research outputs found
Entrepreneurship and Role Models
In the media role models are increasingly being acknowledged as an influential factor in explaining the reasons for the choice of occupation and career. Various conceptual studies have proposed links between role models and entrepreneurial intentions. However, empirical research aimed at establishing the importance of role models for (nascent) entrepreneurs is scarce. Knowledge of the presence of entrepreneurial role models, their specific functions and characteristics is therefore limited. Our explorative empirical study is a first step towards filling this gap. Our study is based on the outcomes of a questionnaire completed by a representative sample of 292 entrepreneurs in three major Dutch cities - entrepreneurs who have recently started up a business in the retail, hotel and restaurant sectors, business services and other services. We provide indications of the presence and importance of entrepreneurial role models, the function of these role models, the similarity between the entrepreneur and the role model, and the strength of their relationship
Determinants of job satisfaction: a European comparison of self-employed and paid employees
The job satisfaction of self-employed and paid-employed workers is analyzed using the European Community Household Panel for the EU-15 covering the years 1994-2001. We distinguish between two types of job satisfaction: job satisfaction in terms of type of work and job satisfaction in terms of job security. Findings from our generalized ordered logit regressions indicate that self-employed individuals as compared to paid employees are more likely to be satisfied with their present jobs in terms of type of work and less likely to be satisfied in terms of job security. The findings also provide many insights into the determinants of the two types of job satisfaction for both self-employed and paid-employed workers
What is the value of entrepreneurship?: a review of recent research
This paper examines to what extent recent empirical evidence can collectively and systematically substantiate the claim that entrepreneurship has important economic value. Hence, a systematic review is provided that answers the question: What is the contribution of entrepreneurs to the economy in comparison to non-entrepreneurs? We study the relative contribution of entrepreneurs to the economy based on four measures that have most widely been studied empirically. Hence, we answer the question: What is the contribution of entrepreneurs to (i) employment generation and dynamics, (ii) innovation, and (iii) productivity and growth, relative to the contributions of the entrepreneurs counterparts, i.e. the control group? A fourth type of contribution studied is the role of entrepreneurship in increasing individuals utility levels. Based on 57 recent studies of high quality that contain 87 relevant separate analyses, we conclude that entrepreneurs have a very important but specific function in the economy. They engender relatively much employment creation, productivity growth and produce and commercialize high quality innovations. They are more satisfied than employees. More importantly, recent studies show that entrepreneurial firms produce important spillovers that affect regional employment growth rates of all companies in the region in the long run. However, the counterparts cannot be missed either as they account for a relatively high value of GDP, a less volatile and more secure labor market, higher paid jobs and a greater number of innovations and they have a more active role in the adoption of innovations
Becoming a new neuron in the adult olfactory bulb
New neurons are continually recruited throughout adulthood in certain regions of the adult mammalian brain. How these cells mature and integrate into preexisting functional circuits remains unknown. Here we describe the physiological properties of newborn olfactory bulb interneurons at five different stages of their maturation in adult mice. Patch-clamp recordings were obtained from tangentially and radially migrating young neurons and from neurons in three subsequent maturation stages. Tangentially migrating neurons expressed extrasynaptic GABAA receptors and then AMPA receptors, before NMDA receptors appeared in radially migrating neurons. Spontaneous synaptic activity emerged soon after migration was complete, and spiking activity was the last characteristic to be acquired. This delayed excitability is unique to cells born in the adult and may protect circuits from uncontrolled neurotransmitter release and neural network disruption. Our results show that newly born cells recruited into the olfactory bulb become neurons, and a unique sequence of events leads to their functional integration
De jure determinants of new firm formation: how the pillars of constitutions influence entrepreneurship
This paper provides empirical evidence supporting the view that constitutions are the primary and fundamental institutional determinant of entrepreneurship. It shows that some of the provisions contained in national constitutions are positively and significantly associated with a standard measure of entrepreneurial dynamics, namely the rate of new business density. Using for 115 countries a novel dataset containing the characteristics of the constitutions enacted in the world, applying an IV-GMM treatment to deal with the endogeneity of constitutional rules, and controlling for de facto variables, the paper finds that provisions about the right to conduct/establish a business, the right to strike, consumer protection, anti-corruption, and compulsory education promote higher rates of new firm formation. Contrasting results are instead obtained for provisions concerning protection of intellectual property rights
Public health insurance and entry into self-employment
We estimate the impact of a differential treatment of paid employees versus
self-employed workers in a public health insurance system on the entry rate
into entrepreneurship. In Germany, the public health insurance system is
mandatory for most paid employees, but not for the selfemployed, who usually
buy private health insurance. Private health insurance contributions are
relatively low for the young and healthy, and until 2013 also for males, but
less attractive at the other ends of these dimensions and if membership in the
public health insurance allows other family members to be covered by
contribution-free family insurance. Therefore, the health insurance system can
create incentives or disincentives to starting up a business depending on the
family’s situation and health. We estimate a discrete time hazard rate model
of entrepreneurial entry based on representative household panel data for
Germany, which include personal health information, and we account for non-
random sample selection. We estimate that an increase in the health insurance
cost differential between self-employed workers and paid employees by 100 euro
per month decreases the annual probability of entry into selfemployment by
0.38 percentage points, i.e. about a third of the average annual entry rate.
The results show that the phenomenon of entrepreneurship lock, which an
emerging literature describes for the system of employer provided health
insurance in the USA, can also occur in a public health insurance system.
Therefore, entrepreneurial activity should be taken into account when
discussing potential health care reforms, not only in the USA and in Germany
AP2γ controls adult hippocampal neurogenesis and modulates cognitive, but not anxiety or depressive-like behavior
Hippocampal neurogenesis has been proposed to participate in a myriad of behavioral responses, both in basal states and in the context of neuropsychiatric disorders. Here, we identify activating protein 2γ 3 (AP2γ 3, also known as Tcfap2c), originally described to regulate the generation of neurons in the developing cortex, as a modulator of adult hippocampal glutamatergic neurogenesis in mice. Specifically, AP2γ 3 is present in a sub-population of hippocampal transient amplifying progenitors. There, it is found to act as a positive regulator of the cell fate determinants Tbr2 and NeuroD, promoting proliferation and differentiation of new glutamatergic granular neurons. Conditional ablation of AP2γ 3 in the adult brain significantly reduced hippocampal neurogenesis and disrupted neural coherence between the ventral hippocampus and the medial prefrontal cortex. Furthermore, it resulted in the precipitation of multimodal cognitive deficits. This indicates that the sub-population of AP2γ 3-positive hippocampal progenitors may constitute an important cellular substrate for hippocampal-dependent cognitive functions. Concurrently, AP2γ 3 deletion produced significant impairments in contextual memory and reversal learning. More so, in a water maze reference memory task a delay in the transition to cognitive strategies relying on hippocampal function integrity was observed. Interestingly, anxiety- and d epressive-like behaviors were not significantly affected. Altogether, findings open new perspectives in understanding the role of specific sub-populations of newborn neurons in the (patho)physiology of neuropsychiatric disorders affecting hippocampal neuroplasticity and cognitive function in the adult brain.We acknowledge the excellent technical expertise of Luís Martins and Andrea
Steiner-Mezzadri. We would also like to acknowledge Magdalena Götz for the
insightful comments on the paper. AMP, PP, ARS, JS, VMS, NDA and JFO received
fellowships from the Portuguese Foundation for Science and Technology (FCT). LP
received fellowship from FCT and her work is funded by FCT (IF/01079/2014) and Bial
Foundation (427/14) projects. This work was cofunded by the Life and Health
Sciences Research Institute (ICVS), and Northern Portugal Regional Operational
Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through
the European Regional Development Fund (FEDER) (projects NORTE-01-0145-
FEDER-000013 and NORTE-01-0145-FEDER-000023). This work has been also funded
by FEDER funds, through the Competitiveness Factors Operational Programme
(COMPETE), and by National funds, through the FCT, under the scope of the project
POCI-01-0145-FEDER-007038info:eu-repo/semantics/publishedVersio
Happiness through leisure
Happiness is important to individuals. If one were to make a judgment based on the vast
amount of self-help books available in any bookstore, the conclusion would have to be that
happiness is a very important aspect of people’s lives. Whether such books actually provide
any solutions to increase happiness is doubtful (Bergsma, 2008). Nevertheless, many are
clearly interested in happiness
The oncological outcomes of isolated limb perfusion and neo-adjuvant radiotherapy in soft tissue sarcoma patients:A nationwide multicenter study
Introduction: Patients with locally extensive high-grade extremity soft tissue sarcomas (eSTS) are often presented in multidisciplinary teams to decide between ablative surgery (amputation) or limb-salvage surgery supplemented with either neo-adjuvant radiotherapy (RT) or induction isolated limb perfusion (ILP). In The Netherlands, ILP typically aims to reduce the size of tumors that would otherwise be considered irresectable, whereas neo-adjuvant RT aims mainly at improving local control and reducing morbidity of required marginal margins. This study presents a 15-year nationwide cohort to describe the oncological outcomes of both pre-operative treatment strategies. Methods: All consecutive patients with locally extensive primary high-grade eSTS surgically treated between 2000 and 2015 at five tertiary sarcoma centers that received neo-adjuvant ILP or RT were included. 169 patients met the inclusion criteria (89 ILP, 80 RT). Median follow-up was 7.3 years. Results: Limb salvage was achieved in 84% of cases in the ILP group (80% for patients with amputation indication) and 96% of cases in the RT group. 5-Year overall survival was 47% in the ILP group, 69% in the RT group. 5-Year local recurrence rate was 14% in the ILP group, 10% in the RT group. Distant metastasis rate was 55% in the ILP group, 36% in the RT group. Conclusion: We find oncological outcomes and limb salvage rates in line with existing literature for both treatment modalities. Whether the tumor was locally advanced with an indication for induction therapy to prevent amputation or morbid surgery appeared to be the main determinant in choosing between neo-adjuvant ILP or RT
GH mediates exercise-dependent activation of SVZ neural precursor cells in aged mice
Here we demonstrate, both in vivo and in vitro, that growth hormone (GH) mediates precursor cell activation in the subventricular zone (SVZ) of the aged (12-month-old) brain following exercise, and that GH signaling stimulates precursor activation to a similar extent to exercise. Our results reveal that both addition of GH in culture and direct intracerebroventricular infusion of GH stimulate neural precursor cells in the aged brain. In contrast, no increase in neurosphere numbers was observed in GH receptor null animals following exercise. Continuous infusion of a GH antagonist into the lateral ventricle of wild-type animals completely abolished the exercise-induced increase in neural precursor cell number. Given that the aged brain does not recover well after injury, we investigated the direct effect of exercise and GH on neural precursor cell activation following irradiation. This revealed that physical exercise as well as infusion of GH promoted repopulation of neural precursor cells in irradiated aged animals. Conversely, infusion of a GH antagonist during exercise prevented recovery of precursor cells in the SVZ following irradiation
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