Entrepreneurial Contexts and Traits of Entrepreneurs

This paper adopts a neo-Darwinian perspective that the entrepreneurial process includes distinctive features that “select” individuals with certain characteristics for participation and success. These individuals are attracted to entrepreneurial situations and their compatible traits enable them to navigate the challenges of entrepreneurial contexts. Furthermore, entrepreneurial environments may reinforce these traits in entrepreneurs, which develop over time in response to the requirements of entrepreneurial activity (Littunen, 2000). The paper begins with a description of early-stage entrepreneurial contexts, considers individual traits that accommodate those contexts, and concludes with a metaphor of entrepreneurs as jazz musicians that captures similarities in context and behavior

An investigation of small-scale motions and the forecasting of wind profiles over short periods of time at Cape Kennedy, Florida

Small scale motions and numerical wind profiles forecasting for short periods at Cape Kenned

BALANCE OF BIOMECHANICAL AND PHYSIOLOGICAL CONTRIBUTIONS TO SWIMMING PERFORMANCE

Swimming is a unique activity carried out in a unique environment. Performance depends on interplay between biomechanical and bioenergetic aspects, thus if we can understand their interaction, as a function of velocity, we can understand the biophysics of swimming. The relationship between stroke frequency and velocity and their impact on drag and efficiency are critical. The biomechanical aspects dictate the velocity-dependent metabolic demands of swimming, thus the maximal performance is determined by the balance of metabolic power among aerobic and anaerobic pathways. Training is a determinant of swimming performance, and applying bioenergetic principles could improve performance

Gravitational Force and the Cardiovascular System

Cardiovascular responses to changes in gravitational force are considered. Man is ideally suited to his 1-g environment. Although cardiovascular adjustments are required to accommodate to postural changes and exercise, these are fully accomplished for short periods (min). More challenging stresses are those of short-term microgravity (h) and long-term microgravity (days) and of gravitational forces greater than that of Earth. The latter can be simulated in the laboratory and quantitative studies can be conducted

Analysing appropriation and usability in social and occupational lives: An investigation of Bangladeshi farmers' use of mobile telephony

Purpose – The purpose of this paper is to understand how Bangladeshi farmers interact with mobile telephony and how they negotiate the resulting difficulties. In doing so, the paper seeks to identify how farmers integrate mobile telephony into their daily lives, and what factors facilitate and limit their use of mobile telephony. Design/methodology/approach – The research was based on ethnographic observation, interviews and focus group discussions, collected through four months of fieldwork, conducted in two remote areas of Bangladesh. Findings – It was found that Bangladeshi farmers' use of mobile telephony is inhibited due to language barriers, a lack of literacy, unfamiliar English terminologies, inappropriate translation to local language (Bengali) and financial constraints. However, the social, occupational and psychological benefits from mobile telephony motivate them to use and appropriate it through inventive use and adaptation. Research limitations/implications – The findings suggest that current understanding of usability needs to be interwoven with that about the appropriation of technology in order to develop a better understanding of the use and consequent integration of a technology in daily lives. Practical implications – The paper adds to the argument for a bottom-up approach for ICT-enabled intervention in development activities and for the mobile telephony manufacturers and network providers it contributes to understanding of the rural consumer market of a developing country. Originality/value – The paper presents an original conceptual diagram that combines the concept of usability and appropriation

Ethnographic Approach to User-Centred Evaluation of Telecentres

Telecentres are considered to be an important means for providing disadvantaged communities with access to Information and Communication Technology (ICT) enabled services. However, there is a limited understanding of how targeted beneficiaries perceive the roles of these telecentres. Using an ethnographic approach, this paper examines the services offered by two telecentres in Bangladesh. An intervention was initiated that enabled groups of farmers to use mobile phones to access services. Based on farmers’ experiences and opinions the authors develop a framework which explicates the dynamic nature of use and appropriation of ICT services

Circadian Disruption with Constant Light Exposure Exacerbates Atherosclerosis in Male \u3cem\u3eApolipoproteinE\u3c/em\u3e-Deficient Mice

Disruption of the circadian system caused by disordered exposure to light is pervasive in modern society and increases the risk of cardiovascular disease. The mechanisms by which this happens are largely unknown. ApolipoproteinE-deficient (ApoE−/−) mice are studied commonly to elucidate mechanisms of atherosclerosis. In this study, we determined the effects of light-induced circadian disruption on atherosclerosis in ApoE−/− mice. We first characterized circadian rhythms of behavior, light responsiveness, and molecular timekeeping in tissues from ApoE−/− mice that were indistinguishable from rhythms in ApoE+/+ mice. These data showed that ApoE−/− mice had no inherent circadian disruption and therefore were an appropriate model for our study. We next induced severe disruption of circadian rhythms by exposing ApoE−/− mice to constant light for 12 weeks. Constant light exposure exacerbated atherosclerosis in male, but not female, ApoE−/− mice. Male ApoE−/− mice exposed to constant light had increased serum cholesterol concentrations due to increased VLDL/LDL fractions. Taken together, these data suggest that ApoE−/− mice are an appropriate model for studying light-induced circadian disruption and that exacerbated dyslipidemia may mediate atherosclerotic lesion formation caused by constant light exposure

Tissue-Specific Function of Period3 in Circadian Rhythmicity

The mammalian circadian system is composed of multiple central and peripheral clocks that are temporally coordinated to synchronize physiology and behavior with environmental cycles. Mammals have three homologs of the circadian Period gene (Per1, 2, 3). While numerous studies have demonstrated that Per1 and Per2 are necessary for molecular timekeeping and light responsiveness in the master circadian clock in the suprachiasmatic nuclei (SCN), the function of Per3 has been elusive. In the current study, we investigated the role of Per3 in circadian timekeeping in central and peripheral oscillators by analyzing PER2::LUCIFERASE expression in tissues explanted from C57BL/6J wild-type and Per3−/− mice. We observed shortening of the periods in some tissues from Per3−/− mice compared to wild-types. Importantly, the periods were not altered in other tissues, including the SCN, in Per3−/− mice. We also found that Per3-dependent shortening of endogenous periods resulted in advanced phases of those tissues, demonstrating that the in vitro phenotype is also present in vivo. Our data demonstrate that Per3 is important for endogenous timekeeping in specific tissues and those tissue-specific changes in endogenous periods result in internal misalignment of circadian clocks in Per3−/− mice. Taken together, our studies demonstrate that Per3 is a key player in the mammalian circadian system

Neon Fine-Structure Line Emission By X-ray Irradiated Protoplanetary Disks

Using a thermal-chemical model for the generic T-Tauri disk of D'Alessio et al. (1999), we estimate the strength of the fine-structure emission lines of NeII and NeIII at 12.81 and 15.55 microns that arise from the warm atmosphere of the disk exposed to hard stellar X-rays. The Ne ions are produced by the absorption of keV X-rays from the K shell of neutral Ne, followed by the Auger ejection of several additional electrons. The recombination cascade of the Ne ions is slow because of weak charge transfer with atomic hydrogen in the case of Ne2+ and by essentially no charge transfer for Ne+. For a distance of 140pc, the 12.81 micron line of Ne II has a flux of 1e-14 erg/cm2s, which should be observable with the Spitzer Infrared Spectrometer and suitable ground based instrumentation. The detection of these fine-structure lines would clearly demonstrate the effects of X-rays on the physical and chemical properties of the disks of young stellar objects and provide a diagnostic of the warm gas in protoplanetary disk atmospheres. They would complement the observed H2 and CO emission by probing vertical heights above the molecular transition layer and larger radial distances that include the location of terrestrial and giant planets.Comment: 24 pages, 5 figure

‘Priming’ exercise and O2 uptake kinetics during treadmill running

We tested the hypothesis that priming exercise would speed kinetics during treadmill running. Eight subjects completed a square-wave protocol, involving two bouts of treadmill running at 70% of the difference between the running speeds at lactate threshold (LT) and max, separated by 6-min of walking at 4 km h−1, on two occasions. Oxygen uptake was measured breath-by-breath and subsequently modelled using non-linear regression techniques. Heart rate and blood lactate concentration were significantly elevated prior to the second exercise bout compared to the first. However, kinetics was not significantly different between the first and second exercise bouts (mean ± S.D., phase II time constant, Bout 1: 16 ± 3 s vs. Bout 2: 16 ± 4 s; slow component amplitude, Bout 1: 0.24 ± 0.10 L min−1vs. Bout 2: 0.20 ± 0.12 L min−1; mean response time, Bout 1: 34 ± 4 s vs. Bout 2: 34 ± 6 s; P > 0.05 for all comparisons). These results indicate that, contrary to previous findings with other exercise modalities, priming exercise does not alter kinetics during high-intensity treadmill running, at least in physically active young subjects. We speculate that the relatively fast kinetics and the relatively small slow component in the control (‘un-primed’) condition negated any enhancement of kinetics by priming exercise in this exercise modality