Optimisation of the Total Oxidant Scavenging Capacity Assay and Application on <i>Euterpe Oleracea</i> Mart. (Açaí) Pulps and Seeds

The antioxidant capacities of commercial and non-commercial pulps and seeds of the Euterpe oleracea Mart., Arecaceae, (açaí) palm were surveyed against peroxyl radicals, peroxynitrite and hydroxyl radicals. Analyses were carried out with the Total Oxidant Scavenging Capacity (TOSC) assay in a modified and automated version. The results were compared to several standard compounds as well as to a number of common European fruit and vegetable juices. Several antioxidants present in açaí pulps and seeds were identified, quantified and their contribution to the overall antioxidant capacities was estimated

Power, politics and patronage

Population growth, poverty and property management problems are often advanced to explain resource degradation in North Yemen. But how do traditional political relations affect resource capture and allocation, particularly among peripheral groups not directly subject to state influence and which value autonomy and self-sufficiency? This paper investigates the socio-economic, political and legal contexts that determine water management among the tribal communities of the Sa'da basin in northern Yemen. Firstly, this paper considers how Islamic and customary law regulating the use of scarce surface water interact to define the relative power of actors over their respective environments. Secondly, it shows that the spatial distribution of irrigated agriculture is largely a function of political factors. Thirdly, it examines actors remarkable ability to resist all forms of control.Pouvoir, politique et patronage. L'adaptation des droits d'eau parmi les tribus des hautes terres du Yémen. -- La croissance démographique, la pauvreté et le mode de gestion de la propriété sont souvent invoqués pour expliquer la dégradation des ressources au Nord-Yémen. Mais comment les rapports politiques influent-ils sur les modes de captation et d'allocation de l'eau parmi des groupes périphériques attachés à leur autonomie et à leur autosuffisance et qui échappent largement aux influences étatiques ? Cet article examine le contexte socioéconomique, politique et juridique qui détermine la gestion de l'eau au sein des communautés tribales du bassin de Sa'da. Il considère d'abord comment le droit musulman et le droit coutumier ayant trait à l'usage d'eaux de surface limitées interagissent et définissent le pouvoir relatif des acteurs sur leurs environnements respectifs. Ensuite, il montre que la distribution spatiale de l'agriculture irriguée est largement déterminée par des facteurs politiques. Enfin, il souligne la remarquable capacité des acteurs à résister à toute forme de contrôle

A computational model of human-robot spatial interactions based on a qualitative trajectory calculus

In this paper we propose a probabilistic sequential model of Human-Robot Spatial Interaction (HRSI) using a well-established Qualitative Trajectory Calculus (QTC) to encode HRSI between a human and a mobile robot in a meaningful, tractable, and systematic manner. Our key contribution is to utilise QTC as a state descriptor and model HRSI as a probabilistic sequence of such states. Apart from the sole direction of movements of human and robot modelled by QTC, attributes of HRSI like proxemics and velocity profiles play vital roles for the modelling and generation of HRSI behaviour. In this paper, we particularly present how the concept of proxemics can be embedded in QTC to facilitate richer models. To facilitate reasoning on HRSI with qualitative representations, we show how we can combine the representational power of QTC with the concept of proxemics in a concise framework, enriching our probabilistic representation by implicitly modelling distances. We show the appropriateness of our sequential model of QTC by encoding different HRSI behaviours observed in two spatial interaction experiments. We classify these encounters, creating a comparative measurement, showing the representational capabilities of the model

Exit Doorway Model for Nuclear Breakup of Weakly Bound Projectiles

We derive closed expressions for the nuclear breakup cross sections in the adiabatic limit using the Austern-Blair theory. These expressions are appropriate for the breakup of weakly bound nuclei. The concept of an exit doorway that mediates the coupling between the entrance channel and the breakup continuum is used. We prove the validity of the scaling law that dictates that the nuclear breakup cross section scales linearly with the radius of the target. We also compare our results for the nuclear breakup cross section of $^{11}$Be, $^8$B on several targets with recent CDCC calculation.Comment: 5 pages, 1 figur

Elastic Scattering and Total Reaction Cross Section for the 6He + 27Al System

The elastic scattering of the radioactive halo nucleus 6He on 27Al target was measured at four energies close to the Coulomb barrier using the RIBRAS (Radioactive Ion Beams in Brazil) facility. The Sao Paulo Potential(SPP) was used and its diffuseness and imaginary strength were adjusted to fit the elastic scattering angular distributions. Reaction cross-sections were extracted from the optical model fits. The reduced reaction cross-sections of 6He on 27Al are similar to those for stable, weakly bound projectiles as {6,7}Li, 9Be and larger than stable, tightly bound projectile as 16O on 27Al.Comment: 7 pages, 1 table, 3 figure

Least-Cost Transportation Planning: Probleme und Potentiale der Übertragung von LCP auf die Mobilität

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Higher order effects in the 16O(d,p)17O^{16}O(d,p)^{17}O and 16O(d,n)17F^{16}O(d,n)^{17}F transfer reactions

Full Coupled Channels Calculations were performed for the $^{16}O(d,n)^{17}F$ and $^{16}O(d,p)^{17}O$ transfer reactions at several deuteron incident energies from $E_{lab}=2.29$ MeV up to 3.27 MeV. A strong polarization effect between the entrance channel and the transfer channels $^{16}O(d,n)^{17}F(1/2^{+},0.495)$ and $^{16}O(d,p)^{17}O(1/2^{+},0.87)$ was observed. This polarization effect had to be taken into account in order to obtain realistic spectroscopic factors from these reactions.Comment: 15 papes, 13 figures, accepted for publication in Phys. Rev.

A schematic model for the direct cross-section in reactions induced by exotic and stable projectiles

A geometric model for the direct contribution of the reaction cross section induced by light ions on different targets is presented. The model separates the total reaction cross section into two components, one for total fusion and another for direct reactions. We show that the direct part scales as $2 \pi Ra$, where $R$ is related to the nuclear radius and $a$ is the width of a ring, which is related to the nuclear diffuseness. A simple expression is presented to calculate the radius $R$ and the width parameter $a$ in terms of the masses and charges of the system. The method is applied to experimental data of exotic, weakly bound, and strongly bound projectiles on several targets. Different diffuseness parameters were obtained for different types of projectiles: exotic n-rich, stable weakly bound, stable strongly bound and exotic p-rich exotic projectiles.Comment: 10 pages, 4 figures, 2 table