Risk tolerance: A perspective on entrepreneurship education

The field of entrepreneurship in South Africa has certain uniquealthough limiting characteristics, including an unconvincing enablingenvironment, a weak entrepreneurial culture and an emergent, andtherefore limited, body of knowledge surrounding the topic ofentrepreneurship. Consequently, entrepreneurship in South Africadoes not hold a strong position in terms of entrepreneurial activityand, in fact, is generally approached with a degree of scepticism. Atthe same time, Maas & Herrington in the Global EntrepreneurshipMonitor (GEM) (Maas & Herrington 2006: 12) indicate categoricallythat an increase in entrepreneurial activity is highly dependent oneffective entrepreneurship education. This study confirmed the factthat education per se may increase the current Total EntrepreneurialActivity rate of 5.29% in South Africa, as compared with 14.8% inother developing countries. An aspect of entrepreneurship that is currently not adequately addressed in entrepreneurship education and training literature is that of risk tolerance and risk-taking of the entrepreneur. Debate on whether entrepreneurs exhibit higher risk tolerance than othermanagers and full-time employed individuals is ongoing andraises the question of whether risk tolerance should be included inentrepreneurship curricula. This study seeks to elaborate on thisdebate

3D climate modeling of close-in land planets: Circulation patterns, climate moist bistability and habitability

The inner edge of the classical habitable zone is often defined by the critical flux needed to trigger the runaway greenhouse instability. This 1D notion of a critical flux, however, may not be so relevant for inhomogeneously irradiated planets, or when the water content is limited (land planets). Here, based on results from our 3D global climate model, we find that the circulation pattern can shift from super-rotation to stellar/anti stellar circulation when the equatorial Rossby deformation radius significantly exceeds the planetary radius. Using analytical and numerical arguments, we also demonstrate the presence of systematic biases between mean surface temperatures or temperature profiles predicted from either 1D or 3D simulations. Including a complete modeling of the water cycle, we further demonstrate that for land planets closer than the inner edge of the classical habitable zone, two stable climate regimes can exist. One is the classical runaway state, and the other is a collapsed state where water is captured in permanent cold traps. We identify this "moist" bistability as the result of a competition between the greenhouse effect of water vapor and its condensation. We also present synthetic spectra showing the observable signature of these two states. Taking the example of two prototype planets in this regime, namely Gl581c and HD85512b, we argue that they could accumulate a significant amount of water ice at their surface. If such a thick ice cap is present, gravity driven ice flows and geothermal flux should come into play to produce long-lived liquid water at the edge and/or bottom of the ice cap. Consequently, the habitability of planets at smaller orbital distance than the inner edge of the classical habitable zone cannot be ruled out. Transiting planets in this regime represent promising targets for upcoming observatories like EChO and JWST.Comment: Accepted for publication in Astronomy and Astrophysics, complete abstract in the pdf, 18 pages, 18 figure

Transient conditions for biogenesis on low-mass exoplanets with escaping hydrogen atmospheres

Exoplanets with lower equilibrium temperatures than Earth and primordial hydrogen atmospheres that evaporate after formation should pass through transient periods where oceans can form on their surfaces, as liquid water can form below a few thousand bar pressure and H2-H2 collision-induced absorption provides significant greenhouse warming. The duration of the transient period depends on the planet size, starting H2 inventory and star type, with the longest periods typically occurring for planets around M-class stars. As pre-biotic compounds readily form in the reducing chemistry of hydrogen-rich atmospheres, conditions on these planets could be favourable to the emergence of life. The ultimate fate of any emergent organisms under such conditions would depend on their ability to adapt to (or modify) their gradually cooling environment.Comment: 19 pages, 5 figures, accepted for publication in Icaru

The views of HR practitioners on ethical issues within organisations.

This article reports on the results of a survey conducted among human resource practitioners in South Africa regarding their involvement in and experience of business ethics and unethical behaviour in their organisations. The results of the study concur with the theoretical perception that human resource managers have an important role to play in the institutionalisation of good ethical behaviour in the organisation, with the majority of respondents reporting that the human resource department is a primary resource for ethical initiatives and that human resource professionals are involved in the formulation of ethics policies. The article provides some insights in terms of the role of the human resource managers in the management of ethics. In so doing, an attempt is made to address the question of whether human resource managers should be the drivers of ethics initiatives in the organisation.Business Managemen

Increased insolation threshold for runaway greenhouse processes on Earth like planets

Because the solar luminosity increases over geological timescales, Earth climate is expected to warm, increasing water evaporation which, in turn, enhances the atmospheric greenhouse effect. Above a certain critical insolation, this destabilizing greenhouse feedback can "runaway" until all the oceans are evaporated. Through increases in stratospheric humidity, warming may also cause oceans to escape to space before the runaway greenhouse occurs. The critical insolation thresholds for these processes, however, remain uncertain because they have so far been evaluated with unidimensional models that cannot account for the dynamical and cloud feedback effects that are key stabilizing features of Earth's climate. Here we use a 3D global climate model to show that the threshold for the runaway greenhouse is about 375 W/m$^2$, significantly higher than previously thought. Our model is specifically developed to quantify the climate response of Earth-like planets to increased insolation in hot and extremely moist atmospheres. In contrast with previous studies, we find that clouds have a destabilizing feedback on the long term warming. However, subsident, unsaturated regions created by the Hadley circulation have a stabilizing effect that is strong enough to defer the runaway greenhouse limit to higher insolation than inferred from 1D models. Furthermore, because of wavelength-dependent radiative effects, the stratosphere remains cold and dry enough to hamper atmospheric water escape, even at large fluxes. This has strong implications for Venus early water history and extends the size of the habitable zone around other stars.Comment: Published in Nature. Online publication date: December 12, 2013. Accepted version before journal editing and with Supplementary Informatio

The views of HR practitioners on ethical issues within organisations: A South African perspective

This article reports on the results of a survey conducted among human resource practitioners in South Africa regarding their involvement in and experience of business ethics and unethical behaviour in their organisations. The results of the study concur with the theoretical perception that human resource managers have an important role to play in the institutionalisation of good ethical behaviour in the organisation, with the majority of respondents reporting that the human resource department is a primary resource for ethical initiatives and that human resource professionals are involved in the formulation of ethics policies. The article provides some insights in terms of the role of the human resource managers in the management of ethics. In so doing, an attempt is made to address the question of whether human resource managers should be the drivers of ethics initiatives in the organisation

Global modelling of the early Martian climate under a denser CO2 atmosphere: Water cycle and ice evolution

We discuss 3D global simulations of the early Martian climate that we have performed assuming a faint young Sun and denser CO2 atmosphere. We include a self-consistent representation of the water cycle, with atmosphere-surface interactions, atmospheric transport, and the radiative effects of CO2 and H2O gas and clouds taken into account. We find that for atmospheric pressures greater than a fraction of a bar, the adiabatic cooling effect causes temperatures in the southern highland valley network regions to fall significantly below the global average. Long-term climate evolution simulations indicate that in these circumstances, water ice is transported to the highlands from low-lying regions for a wide range of orbital obliquities, regardless of the extent of the Tharsis bulge. In addition, an extended water ice cap forms on the southern pole, approximately corresponding to the location of the Noachian/Hesperian era Dorsa Argentea Formation. Even for a multiple-bar CO2 atmosphere, conditions are too cold to allow long-term surface liquid water. Limited melting occurs on warm summer days in some locations, but only for surface albedo and thermal inertia conditions that may be unrealistic for water ice. Nonetheless, meteorite impacts and volcanism could potentially cause intense episodic melting under such conditions. Because ice migration to higher altitudes is a robust mechanism for recharging highland water sources after such events, we suggest that this globally sub-zero, `icy highlands' scenario for the late Noachian climate may be sufficient to explain most of the fluvial geology without the need to invoke additional long-term warming mechanisms or an early warm, wet Mars.Comment: Minor revisions to text, one new table, figs. 1,3 11 and 18 redon