If We Want Entrepreneurs We Need to Provide the Right Environment

This paper takes the notion that entrepreneurs are good for economies and outlines what countries can do to encourage entrepreneurship. It suggests that citizen rights and freedom are directly related with entrepreneurial activity. Illegal entrepreneurial activity is mentioned as an outlet in repressive localities. It lists areas of the world where freedom exists and where it does not. Historical, current and country examples are given to illustrate these suppositions and the paper concludes with the role of entrepreneurship in world agribusiness.Entrepreneurs, country freedom index, innovation, ownership, agribusiness, product, Agribusiness,

Selecting Profitable Enterprises or Selling the Farm

Farm Management,

Free Cash Flow Is At Least as Important as Profit in Assessing a Farm Firm

This paper suggests that most small agribusinesses can use a short cut to see how their firms are doing financially. The short cut requires that they calculate and follow (1) profit and (2) free cash flow. Both are defined and clarified. The reason for this short cut is that most small firm owners do not do enough financial analysis and that this simple and quick study may encourage them. The paper does not encourage the substitution of these two numbers for a proper analysis. They are useful but more of a bait to land the full course.Financial analysis, small agribusiness firms, profit, free cash flow, allocation, income statement, Agricultural Finance,

Toward detailed prominence seismology - I. Computing accurate 2.5D magnetohydrodynamic equilibria

Context. Prominence seismology exploits our knowledge of the linear eigenoscillations for representative magnetohydro- dynamic models of filaments. To date, highly idealized models for prominences have been used, especially with respect to the overall magnetic configurations. Aims. We initiate a more systematic survey of filament wave modes, where we consider full multi-dimensional models with twisted magnetic fields representative of the surrounding magnetic flux rope. This requires the ability to compute accurate 2.5 dimensional magnetohydrodynamic equilibria that balance Lorentz forces, gravity, and pressure gradients, while containing density enhancements (static or in motion). Methods. The governing extended Grad-Shafranov equation is discussed, along with an analytic prediction for circular flux ropes for the Shafranov shift of the central magnetic axis due to gravity. Numerical equilibria are computed with a finite element-based code, demonstrating fourth order accuracy on an explicitly known, non-trivial test case. Results. The code is then used to construct more realistic prominence equilibria, for all three possible choices of a free flux-function. We quantify the influence of gravity, and generate cool condensations in hot cavities, as well as multi- layered prominences. Conclusions. The internal flux rope equilibria computed here have the prerequisite numerical accuracy to allow a yet more advanced analysis of the complete spectrum of linear magnetohydrodynamic perturbations, as will be demonstrated in the companion paper.Comment: Accepted by Astronomy & Astrophysics, 15 pages, 15 figure

Convective magneto-rotational instabilities in accretion disks

We present a study of instabilities occuring in thick magnetized accretion disks. We calculate the growth rates of these instabilities and characterise precisely the contribution of the magneto-rotational and the convective mechanism. All our calculations are performed in radially stratified disks in the cylindrical limit. The numerical calculations are performed using the appropriate local dispersion equation solver discussed in Blokland et al. (2005). A comparison with recent results by Narayan et al. (2002) shows excellent agreement with their approximate growth rates only if the disks are weakly magnetized. However, for disks close to equipartition, the dispersion equation from Narayan et al. (2002) loses its validity. Our calculations allow for a quantitative determination of the increase of the growth rate due to the magneto-rotational mechanism. We find that the increase of the growth rate for long wavelength convective modes caused by this mechanism is almost neglible. On the other hand, the growth rate of short wavelength instabilities can be significantly increased by this mechanism, reaching values up to 60%.Comment: 10 pages, 9 figures, Accepted for publication in Astronomy & Astrophysic

The ECM as a driver of fibroblast senescence and disrupted epithelial repair in IPF

Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disease with a mean survival of 3-5 years after diagnosis. IPF is characterised by accumulation of fibroblasts and extracellular matrix (ECM) leading to stiffening, and destruction of lung parenchyma and alveoli. The exact mechanisms that underlie IPF pathology remain unclear, but evidence suggests that cellular senescence, a hallmark of ageing, may play an important role in disease development, with specific changes observed in the ECM also recognised as major contributors to disease progression. However, the exact role of fibroblast senescence and the regulation of senescence by the ECM remains to be elucidated. The aim of this thesis was to investigate the contribution of ECM to fibroblast senescence, and the subsequent impact on alveolar cell regeneration. In lung fibroblasts cultured on stiff matrices or on ECM deposited by IPF or non-IPF fibroblasts we analysed markers of senescence, and then assessed the effect of fibroblast senescence on alveolar cell regeneration. Matrices mimicking IPF lung tissue stiffness upregulated cellular senescence and fibrosis markers; α-smooth muscle actin, collagen 1α1, fibulin-1, Interleukin-6 and decorin. IPF fibroblast-deposited-ECM did not directly modulate these senescence markers, but rather induced upregulation of transforming growth factor-β1 and connective tissue growth factor. Finally, senescence and IPF fibroblasts reduced proliferation of alveolar epithelial cells, while the presence of fibroblasts, independent of disease status, induced epithelial cell migration. These studies indicate that IPF ECM is a strong regulator of cell function, while fibroblast senescence leads to impaired wound healing of alveolar epithelial cells

Kostprijs van melk 2007: voorlopige resultaten

Op basis van voorlopige bedrijfsresultaten van 2007 is de kostprijs van melk van dat jaar berekend op gemiddeld 42 euro per 100 kg melk. Naast de voorlopige kostprijs van melk beschrijft dit artikel de ontwikkeling van de kosten en opbrengsten van 2001 tot en met 2007