On the Representation Theory of Orthofermions and Orthosupersymmetric Realization of Parasupersymmetry and Fractional Supersymmetry

We construct a canonical irreducible representation for the orthofermion algebra of arbitrary order, and show that every representation decomposes into irreducible representations that are isomorphic to either the canonical representation or the trivial representation. We use these results to show that every orthosupersymmetric system of order $p$ has a parasupersymmetry of order $p$ and a fractional supersymmetry of order $p+1$.Comment: 13 pages, to appear in J. Phys. A: Math. Ge

Activity analysis of coffee growers in complex agroforestry systems, understanding the farmers' pratices

In coffee based agroforestry systems, biodiversity management by farmers is a promising lever for innovation to promote system sustainability and increase income. We hypothesized that the co-design of agroforestry cropping systems based on ecological process, and on implementation of innovative practices have to take into account the reality of the technical work as well as the farmer concerns and the knowledge leading to the actual plot management. The aim of this study is to examine how coffee farmers understand the diversity of their agroforestry systems and how do they manage it through their practices. We have developed an original methodology based on the activity analysis applied to the study of the shade trees regulation practices in the agroforestry coffee plot by coffee growers. The activity analysis is interested in human activity with a view to transforming and designing work situations. According to Theureau (2010), considering enaction paradigm, activity is considered as a dynamic of asymmetrical interaction between an actor and his environment1. Thus, human action is not considered to the actual achievement of a predetermined program resulting from the application of decision rules2. First, semi-structured interviews were conducted to understand the systems and the cropping practices drivers. Then, practices were studied in real situation, through participant observation and the use of methods of verbalization during practice, of self-confrontation and farmer-guided practice1. This study took place in Costa Rica (Turrialba). Agroforestry systems consists of coffee (Coffea arabica) and various types of shade tree species. Our results highlight each action carried out by the coffee grower, associated with farmers indicators, considered as the factors that farmer take into account in the agroforestry environment against the background of his concerns, knowledge or habits. These indicators inform about complexity of interactions between the coffee grower and his environment. This interaction occurred at several levels: for a systemic management (to favor the ecological processes like disease regulation), for an ergonomic management (to favor movements, or reduce risk of injury), for a personal management (based on an affective relation with the biotope). In that respect, shade tree regulation is not only intended to increase the incident light energy received by coffee, but also driven by other motivations. The re-design of innovative and sustainable cropping systems has to take into account the interaction between diversity of human situations and the agroforestry system complexity. In this context, how can practices be transformed? How can we support farmers to think about their own practices and initiate changes specific to them? The activity analysis is an efficient framework to nourish the thinking on current management practices and a promising way to support their progressive transformation in complex agroforestry systems

Palm oil yield potential of oil palm (Elaeis guineensis) seeds developed in a network by Cirad and its partners

Over the last decade, there was very strong growth in the demand for vegetable oils and fats (+ 4.6% per year) and the oils extracted from oil palm fruits greatly contributed to satisfying those needs. Food demand continues to increase, as do traditional uses (cosmetics and oleo chemistry). A new demand for use as bio fuel also needs to be taken into account (1% of current consumption). For oil palm, high-yielding planting material that is as resistant as possible to diseases will be part of the answer proposed by breeders. The breeding scheme primarily involves a reciprocal recurrent selection scheme (RRS) which has been adapted to the biological constraints of the oil palm. The RRS recommended by CIRAD uses, in the form of hybrids, the heterosis effect obtained by crossing origins with complementary characteristics (group A) x (group B). It is also possible to include pedigree selection phases (A self or B self), which cannot really be considered as part of RRS, but the two strategies are complementary. In the oil palm, the general combining ability (GCA) for yield of a parent can only be known by assessing the value of the families it generates. However, some parental traits are heritable enough for it to be efficient to select them: vertical growth, mesocarp/fruit percentage, oil/mesocarp and the number of bunches produced. In order to assess the parental combining ability, we propose a scheme that makes it possible to test all family and each parent. Such a design makes it possible to evaluate the value of all the crosses by removing the inherent trial effect, and the planting year effect. It makes it possible to compare all the parents used in the design with each other. The share of variability explained by an additive model has been calculated. As an example, the Aek Loba design is described. Our study focuses on the mature period for the first 17 trials that have been observed up to 8 years (254 crosses, 114 parents in group A, and 112 in group B). At the progeny level, when selection is strong (8%) the gain recorded for oil production in the mature phase is slightly over 14%. That gain is obtained in an almost balanced way through progress in the extraction rate (+6.5%) and in FFB production (+7.2%). The average contribution of the best parents parent for oil production in the mature phase is around + 700 kg/ha/year. A cross carried out between two good parents leads to a gain of 1 400 kg/ha/year of oil. Some parents provide a significant gain, of more than 3 points, for the extraction rate (i.e. around +12% if the OER increases from 26% to 29%). The R2 between the observed values and the predicted values is 0.9: a purely additive model explains a very large share of the variability observed. Genetic gain will be maximum if we select parents for their GCA: even a moderate selection pressure (16%) leads to substantial genetic progress. In this case, the expected gains are 8% for the extraction rate, more than 9% for FFB production and 17 to 18% for palm oil production. (Résumé d'auteur

Identifying Arkansas Food Desert Blocks Suitable for a Peer-to-Peer Modeled Food Redistribution Program

Abstract Nearly 10% of Americans reside in low-income urban food deserts which are low-income areas that lack access to affordable and nutritious foods. Food deserts in Arkansas contribute to a food insecurity rate above the national average, making it one of the most food insecure states in the country. Increased internet usage and consumer interest in sharing based companies contribute to the idea of a sharing, or peer-to-peer (P2P) style food redistribution program. The objective of this study is to identify which of the 186,211census blocks in the state of Arkansas are food deserts and best suited for and in the most need, based on an identified set of criteria, of a P2P food redistribution program. A multi-criteria decision analysis was conducted using population, internet access, vulnerable communities, and vehicle availability as criteria. Results suggest that based upon the close proximity of priority areas, transportation access, ethnic/racial diversity, and the number of possible collection locations, Pulaski County be targeted for a P2P food redistribution pilot program

Low efficacy of the combination artesunate plus amodiaquine for uncomplicated falciparum malaria among children under 5 years in Kailahun, Sierra Leone.

OBJECTIVE: In 2004, Sierra Leone adopted artesunate plus amodiaquine as first-line antimalarial treatment. We evaluated the efficacy of this combination in Kailahun, where a previous study had shown 70.2% efficacy of amodiaquine in monotherapy. METHODS: Method and outcome classification of the study complied with WHO guidelines. Children 6-59 months with uncomplicated malaria were followed-up for 28 days. PCR genotyping was used to distinguish recrudescence from reinfection. Reinfections were reclassified as cured. RESULTS: Of 172 children who were referred to the study clinic, 126 satisfied inclusion criteria and were enrolled. No early treatment failures were reported. The day 14, efficacy was 98.2% (95% CI: 93.8-99.8). Of 65 recurrent parasitaemias analysed by PCR, 17 were recrudescences. The PCR-adjusted day 28 efficacy was 84.5% (95% CI: 76.4-90.7). All true failures occurred in the last 8 days of follow-up. Of 110 children who completed the 28-day follow-up, 54 (49.1%) experienced a novel infection. CONCLUSION: The efficacy of this combination was disappointing. The high reinfection rate suggested little prophylactic effect. In Kailahun a more efficacious combination might be necessary in the future. The efficacy of AS + AQ needs to be monitored in Kailahun and in the other regions of Sierra Leone

Magnetic and transport properties of amorphous ferro magnetic Gd-Au, Gd-Ni and Gd-Co alloys obtained by splat-cooling

We present the results of magnetization and transport measurements on amorphous Gd_(80)Au_(20), Gd_(68)Ni_(32) and Gd_(67)Co_(33) alloys over a temperature range of 1.8-300°K in fields up to 75 kOe. These ferromagnetic alloys obtained by splat-cooling have Curie temperatures Tcof 150, 125 and 175°K, respectively. The saturation moment per Gd atom extrapolated to 0°K is estimated to be 7± 0.1 μB. The exchange integrals for Gd-Au and Gd-Ni are determined from the value of Tcand from the temperature dependence of the saturation magnetization. The zero-field resistivity for Gd-Ni and Gd-Co exhibits maxima around Tc. We present some preliminary results of magnetoresistivity measurements with applied field parallel and perpendicular to the foil plane. The anisotropy is in-plane for Gd-Co. For the Gd-Au and Gd-Ni alloys, there is no well-defined easy axis

QSO hosts and environments at z=0.9 to 4.2: JHK images with adaptive optics

We have observed nine QSOs with redshifts 0.85 to 4.16 at near-IR wavelengths with the adaptive optics bonnette of the Canada-France-Hawaii telescope. Exposure times ranged from 1500 to 24000s (mostly near 7000s) in J, H, or K bands, with pixels 0.035 arcsec on the sky. The FWHM of the co-added images at the location of the quasars are typically 0.16 arcsec. Including another QSO published previously, we find associated QSO structure in at least eight of ten objects, including the QSO at z = 4.16. The structures seen in all cases include long faint features which appear to be tidal tails. In four cases we have also resolved the QSO host galaxy, but find them to be smooth and symmetrical: future PSF removal may expand this result. Including one object previously reported, of the nine objects with more extended structure, five are radio-loud, and all but one of these appear to be in a dense small group of compact galaxy companions. The radio-quiet objects do not occupy the same dense environments, as seen in the NIR. In this small sample we do not find any apparent trends of these properties with redshift, over the range 0.8 < z < 2.4. The colors of the host galaxies and companions are consistent with young stellar populations at the QSO redshift. Our observations suggest that adaptive optic observations in the visible region will exhibit luminous signatures of the substantial star-formation activity that must be occurring.Comment: 22 pages including 10 tables, plus 11 figures. To appear in A

Sudden To Adiabatic Transition in Beta Decay

We discuss effects in beta decays at very low beta energies, of the order of the kinetic energies of atomic electrons. As the beta energy is lowered the atomic response changes from sudden to adiabatic. As a consequence, the beta decay rate increases slightly and the ejection of atomic electrons (shake off) and subsequent production of X rays is turned off. We estimate the transition energy and the change in decay rate. The rate increase is largest in heavy atoms, which have a small Q value in their decay. The X ray switch-off is independent of Q value.Comment: 6 pages LaTe