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

The effect of vacuum polarisation on muon-proton scattering at small energies and angles

We give a compact expression for the unpolarised differential cross section for muon-proton scattering in the one photon exchange approximation. The effect of adding the vacuum polarisation amplitude to the no-spin-flip amplitude for one photon exchange is calculated at small energies and scattering angles and is found to be negligible for present experiments.Comment: 6 pages, one figur

Mechanically Compliant Grating Reflectors for Optomechanics

We demonstrate micromechanical reflectors with a reflectivity as large as 99.4% and a mechanical quality factor Q as large as 7.8*10^5 for optomechanical applications. The reflectors are silicon nitride membranes patterned with sub-wavelength grating structures, obviating the need for the many dielectric layers used in conventional mirrors. We have employed the reflectors in the construction of a Fabry-Perot cavity with a finesse as high as F=1200, and used the optical response to probe the mechanical properties of the membrane. By driving the cavity with light detuned to the high-frequency side of a cavity resonance, we create an optical antidamping force that causes the reflector to self-oscillate at 211 kHz

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

International Rice Outlook: International Rice Baseline Projections 2021–2031

The war in Ukraine and the lingering effects of the COVID-19 pandemic are pushing input costs to record levels. Although rice prices have increased some in the last several months, production costs have increased more than proportionally, undermining rice profitability. We project global rice production will surpass global rice consumption for most of the coming decade, with a small deficit developing by the end of the projected period. The projected growth in production is almost exclusively due to productivity gains since the global rice area is projected to increase only marginally by 2029–2031. The projected growth in global rice consumption is exclusively based on population growth, as the average global per-capita consumption of rice is estimated to decrease in the coming decade. The international price of long-grain and medium-grain rice is projected to increase in nominal terms but decrease in real terms in the next decade due to ample rice supplies. We project that rice demand in Africa will continue to grow at a high pace, thus supporting a fast growth in regional production and imports. Global rice trade is projected to increase in nominal and relative (to supply) terms, with Africa being the main driver of the expansion. Rice exports will remain highly concentrated among the top-5 exporters. India will remain the largest exporter of rice, while Thailand will consolidate as the second largest exporter in the coming decade. Myanmar and Cambodia are expected to grow their export market share, while Vietnam, Pakistan, and the U.S. are expected to lose market share in the coming decade. On the rice import side, we project that China, the Philippines, the EU, and Saudi Arabia will lose market share, while Nigeria, Cote d’Ivoire, and Iran will grow their market shares by 2029–2031 relative to the situation in 2018–2020

International Rice Outlook: International Rice Baseline Projections 2020-2030

The coronavirus (COVID-19) pandemic and subsequent lockdowns impacted all economies worldwide and created an economic recession far graver than the Great Recession, contracting the global growth of gross domestic product (GDP) nearly by 4.0% in 2020, compared to -2.0% in 2009 (IHS Markit database). COVID-19 disrupted global and local food supply chains, and resulted in a significant increase in food prices (FAO, 2021). Both global and domestic rice prices increased, driven primarily by temporary export restrictions imposed by several leading rice exporters, such as Vietnam and Myanmar. The market uncertainty also created in panic-buying and hoarding; consequently, the rice demand spiked in similar to that was observed during the 2007- 2008 rice crisis. For example, Thai 100% B and Vietnamese 5% long-grain rice prices increased by 30% and 25%, respectively, between March and May 2020 relative to the same period in 2019 (Fig. 1). Although prices in the international market have receded some since then, they remain higher than expected despite the record-high global rice production in 2020

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

Scald risk in social housing can be reduced through thermostatic control system without increasing Legionella risk: a cluster randomised trial.

OBJECTIVE: To quantify the effects of a thermostatic control system in social (public) housing on the prevalence of dangerous (>60°C) water temperatures and on fuel consumption. DESIGN: Pair-matched double-blind cluster randomised controlled trial. SETTING: Social housing in a deprived inner-London borough. PARTICIPANTS: 150 households recruited as clusters from 22 social housing estates. Four small estates were combined into two clusters (resulting in a total of 10 pairs of clusters). INTERVENTION: Social housing estate boiler houses were randomised to a thermostatic control sterilisation programme (heating water to 65°C during 00:00-06:00 h and to 50°C from 06:00 to 00:00 h daily) or to standard control (constant temperature 65°C). MAIN OUTCOME MEASURES: Water temperature over 60°C ('dangerous') after running taps for 1 min and daily fuel consumption (cubic feet of gas). RESULTS: 10 clusters (80 households) were allocated to the sterilisation programme and 10 clusters (70 households) to control, of which 73 and 67 households, respectively, were analysed. Prevalence of dangerous (>60°C) hot water temperatures at 1 min was significantly reduced with the sterilisation programme (mean of cluster prevalence 1% in sterilisation programme group vs 34% in control group; absolute difference 33%, 95% CI 12% to 54%; p=0.006). Prevalence of high (>55°C) hot water temperatures at 1 min was significantly reduced (31% sterilisation vs 59% control; absolute difference 28%, 95% CI 9% to 47%; p=0.009). Gas consumption per day reduced more in the control group than in the sterilisation programme group, although not statistically significantly (p=0.125). CONCLUSIONS: The thermostatic control with daily sterilisation was effective in capping hot water temperatures and therefore reduced scald risk. Although expected to save energy, fuel consumption was increased relative to the control group. Trial registration ClinicalTrials.gov ID: NCT00874692

The Scattering Approach to the Casimir Force

We present the scattering approach which is nowadays the best tool for describing the Casimir force in realistic experimental configurations. After reminders on the simple geometries of 1d space and specular scatterers in 3d space, we discuss the case of stationary arbitrarily shaped mirrors in electromagnetic vacuum. We then review specific calculations based on the scattering approach, dealing for example with the forces or torques between nanostructured surfaces and with the force between a plane and a sphere. In these various cases, we account for the material dependence of the forces, and show that the geometry dependence goes beyond the trivial {\it Proximity Force Approximation} often used for discussing experiments.Comment: Proceedings of the QFEXT'09 conference (Oklahoma, 2009

The dynamics of planetary nebulae in the Galaxy: evidence for a third integral

We present a dynamical analysis of 673 galactic Planetary Nebulae, using a two-integral axisymmetric model with a Kuzmin-Kutuzov St\"{a}ckel potential. The method fits the kinematics to the projected moments of a distribution function, by means of Quadratic Programming. The 2.2 $\mu$m COBE brightness map has been used after correction for the interstellar extinction as a projected star counts map in the modeling, because it constitutes a galactic distribution view of evolved red populations which are considered to be the progenitors of PNe. The model we have obtained provides a 2-integral distribution function for the COBE 2.2 $\mu$m map, and thus {\it a fortiori} a deprojection of it, which allows moreover the identification of all the major Galactic components. We derive the density laws for them. The projected velocity dispersions are not well fitted though, especially in the disk, which points at the likely presence of a third integral. If this result can be confirmed by additional data, this would mean that for the first time the presence and importance of a third integral on a global scale is demonstrated.Comment: 9 pages, uuencoded gzipped postscript file, 9 figures include