Recommendations to the formulation of EU regulation 2092/91 on livestock production

Within the SAFO network, the workpackage on standard development has focussed on the topic, on how and to what degree the EU-Regulations con-tribute to the objective of a high status of anima health and food safety in organic livestock production. Results and conclusions from the discussions at 5 SAFO workshops are presented

An ϵ\epsilon-expansion for Small-World Networks

I construct a well-defined expansion in $\epsilon=2-d$ for diffusion processes on small-world networks. The technique permits one to calculate the average over disorder of moments of the Green's function, and is used to calculate the average Green's function and fluctuations to first non-leading order in $\epsilon$, giving results which agree with numerics. This technique is also applicable to other problems of diffusion in random media.Comment: 7 pages Europhysics style, 3 figure

Probability distributions for polymer translocation

We study the passage (translocation) of a self-avoiding polymer through a membrane pore in two dimensions. In particular, we numerically measure the probability distribution Q(T) of the translocation time T, and the distribution P(s,t) of the translocation coordinate s at various times t. When scaled with the mean translocation time , Q(T) becomes independent of polymer length, and decays exponentially for large T. The probability P(s,t) is well described by a Gaussian at short times, with a variance that grows sub-diffusively as t^{\alpha} with \alpha~0.8. For times exceeding , P(s,t) of the polymers that have not yet finished their translocation has a non-trivial stable shape.Comment: 5 pages, 4 figure

Bowel Perforation Secondary to Illegally Induced Abortion: a Tertiary Hospital Experience in Tanzania.

Bowel perforation though rarely reported is a serious complication of induced abortion, which is often performed illegally by persons without any medical training in developing countries. A sudden increase in the number of patients in our centre in recent years prompted the authors to analyze this problem. The study was conducted to describe our own experiences in the surgical management of these patients. This was a retrospective study involving patients who were jointly managed by the surgical and gynecological teams at Bugando Medical Centre (BMC) for bowel perforation secondary to illegally induced abortion from January 2002 to December 2011. The statistical analysis was performed using SPSS version 17.0. A total of 68 patients (representing 4.2% of cases) were enrolled in the study. Their ages ranged from 14 to 45 years with a median age of 21 years. Majority of patients were, secondary school students/leavers (70.6%), unmarried (88.2%), nulliparous (80.9%), unemployed (82.4%) and most of them were dependent member of the family. Previous history of contraceptive use was reported in only 14.7% of cases. The majority of patients (79.4%) had procured the abortion in the 2nd trimester. Dilatation and curettage (82.4%) was the most common reported method used in procuring abortion. The interval from termination of pregnancy to presentation in hospital ranged from 1 to 14 days (median 6 days ). The ileum (51.5%) and sigmoid colon (22.1%) was the most common portions of the bowel affected. Resection and anastomosis with uterine repair was the most common (86.8%) surgical procedure performed. Complication and mortality rates were 47.1% and 10.3% respectively. According to multivariate logistic regression analysis, gestational age at termination of pregnancy, delayed presentation, delayed surgical treatment and presence of complications were significantly associated with mortality (P<0.001). The overall median length of hospital stay (LOS) was 18 days (1day to 128 days ). Patients who developed complications stayed longer in the hospital, and this was statistically significant (P=0.012). Bowel perforation following illegally induced abortion is still rampant in our environment and constitutes significantly to high maternal morbidity and mortality. Early recognition of the diagnosis, aggressive resuscitation and early institution of surgical management is of paramount importance if morbidity and mortality associated with bowel perforation are to be avoided

Lattice Gas Dynamics; Application to Driven Vortices in Two Dimensional Superconductors

A continuous time Monte Carlo lattice gas dynamics is developed to model driven steady states of vortices in two dimensional superconducting networks. Dramatic differences are found when compared to a simpler Metropolis dynamics. Subtle finite size effects are found at low temperature, with a moving smectic that becomes unstable to an anisotropic liquid on sufficiently large length scales.Comment: 5 pages, 4 figure

Crystal lattice properties fully determine short-range interaction parameters for alkali and halide ions

Accurate models of alkali and halide ions in aqueous solution are necessary for computer simulations of a broad variety of systems. Previous efforts to develop ion force fields have generally focused on reproducing experimental measurements of aqueous solution properties such as hydration free energies and ion-water distribution functions. This dependency limits transferability of the resulting parameters because of the variety and known limitations of water models. We present a solvent-independent approach to calibrating ion parameters based exclusively on crystal lattice properties. Our procedure relies on minimization of lattice sums to calculate lattice energies and interionic distances instead of equilibrium ensemble simulations of dense fluids. The gain in computational efficiency enables simultaneous optimization of all parameters for Li+, Na+, K+, Rb+, Cs+, F-, Cl-, Br-, and I- subject to constraints that enforce consistency with periodic table trends. We demonstrate the method by presenting lattice-derived parameters for the primitive model and the Lennard-Jones model with Lorentz-Berthelot mixing rules. The resulting parameters successfully reproduce the lattice properties used to derive them and are free from the influence of any water model. To assess the transferability of the Lennard-Jones parameters to aqueous systems, we used them to estimate hydration free energies and found that the results were in quantitative agreement with experimentally measured values. These lattice-derived parameters are applicable in simulations where coupling of ion parameters to a particular solvent model is undesirable. The simplicity and low computational demands of the calibration procedure make it suitable for parametrization of crystallizable ions in a variety of force fields.Comment: 9 pages, 5 table

XMM-Newton observations of the spiral galaxy M74 (NGC 628)

The face-on spiral galaxy M74 (NGC 628) was observed by XMM on 2002 February 2. In total, 21 sources are found in the inner 5' from the nucleus (after rejection of a few sources associated to foreground stars). Hardness ratios suggest that about half of them belong to the galaxy. The higher-luminosity end of the luminosity function is fitted by a power-law of slope -0.8. This can be interpreted as evidence of ongoing star formation, in analogy with the distributions found in disks of other late-type galaxies. A comparison with previous Chandra observations reveals a new ultraluminous X-ray transient (L_x \~ 1.5 x 10^39 erg/s in the 0.3--8 keV band) about 4' North of the nucleus. We find another transient black-hole candidate (L_x ~ 5 x 10^38 erg/s) about 5' North-West of the nucleus. The UV and X-ray counterparts of SN 2002ap are also found in this XMM observation.Comment: submitted to ApJL. Based on publicly available data, see http://xmm.vilspa.esa.es/external/xmm_news/items/sn_2002_ap/index.shtm

Resilience of the Internet to random breakdowns

A common property of many large networks, including the Internet, is that the connectivity of the various nodes follows a scale-free power-law distribution, P(k)=ck^-a. We study the stability of such networks with respect to crashes, such as random removal of sites. Our approach, based on percolation theory, leads to a general condition for the critical fraction of nodes, p_c, that need to be removed before the network disintegrates. We show that for a<=3 the transition never takes place, unless the network is finite. In the special case of the Internet (a=2.5), we find that it is impressively robust, where p_c is approximately 0.99.Comment: latex, 3 pages, 1 figure (eps), explanations added, Phys. Rev. Lett., in pres