Noise and Full Counting Statistics of Incoherent Multiple Andreev Reflection

We present a general theory for the full counting statistics of multiple Andreev reflections in incoherent superconducting-normal-superconducting contacts. The theory, based on a stochastic path integral approach, is applied to a superconductor-double barrier system. It is found that all cumulants of the current show a pronounced subharmonic gap structure at voltages $V=2\Delta/en$. For low voltages $V\ll\Delta/e$, the counting statistics results from diffusion of multiple charges in energy space, giving the $p$th cumulant $\propto V^{2-p}$, diverging for $p\geq 3$. We show that this low-voltage result holds for a large class of incoherent superconducting-normal-superconducting contacts.Comment: 4 pages, 4 figure

Measurement of filling factor 5/2 quasiparticle interference: observation of charge e/4 and e/2 period oscillations

A standing problem in low dimensional electron systems is the nature of the 5/2 fractional quantum Hall state: its elementary excitations are a focus for both elucidating the state's properties and as candidates in methods to perform topological quantum computation. Interferometric devices may be employed to manipulate and measure quantum Hall edge excitations. Here we use a small area edge state interferometer designed to observe quasiparticle interference effects. Oscillations consistent in detail with the Aharanov-Bohm effect are observed for integer and fractional quantum Hall states (filling factors 2, 5/3, and 7/3) with periods corresponding to their respective charges and magnetic field positions. With these as charge calibrations, at 5/2 filling factor and at lowest temperatures periodic transmission through the device consistent with quasiparticle charge e/4 is observed. The principal finding of this work is that in addtion to these e/4 oscillations, periodic structures corresponding to e/2 are also observed at 5/2 and at lowest temperatures. Properties of the e/4 and e/2 oscillations are examined with the device sensitivity sufficient to observe temperature evolution of the 5/2 quasiparticle interference. In the model of quasiparticle interference, this presence of an effective e/2 period may empirically reflect an e/2 quasiparticle charge, or may reflect multiple passes of the e/4 quasiparticle around the interferometer. These results are discussed within a picture of e/4 quasiparticle excitations potentially possessing non-Abelian statistics. These studies demonstrate the capacity to perform interferometry on 5/2 excitations and reveal properties important for understanding this state and its excitations.Comment: version 3 contains additional data beyond version 2, 26 pages, 8 figures PNAS 081259910

Fermionic characters for graded parafermions

Fermionic-type character formulae are presented for charged irreduciblemodules of the graded parafermionic conformal field theory associated to the coset $osp(1,2)_k/u(1)$. This is obtained by counting the weakly ordered `partitions' subject to the graded $Z_k$ exclusion principle. The bosonic form of the characters is also presented.Comment: 24 p. This corrects typos (present even in the published version) in eqs (4.4), (5.23), (5.24) and (C.4

Caracterización fisicoquímica y estabilidad oxidativa de aceites comestibles de semillas de sacha inchi microencapsulados y secados por aspersión

The aim of this work was to obtain sacha inchi oil (SIO) microcapsules from two different species, Plukenetia volubilis L. (SIVO) and Plukenetia huayllabambana L. (SIHO), using different biopolymers as wall materials and spray drying technology. The physicochemical characteristics such as encapsulation efficiency, particle size, morphology and oxidative stability were analyzed in order to select the best formulation that could potentially be used as an ingredient in the development of functional food. Bulk SIO and four formulations were tested for each oil ecotype, using different encapsulating agents: maltodextrin (MD), Arabic gum (AG), whey protein concentrate (WPC) and modified starch HI-CAP®-100 (H). Microcapsules made of H presented the highest oxidative stability and encapsulation efficiency compared to AG, AG:MD or AG:MD:WPC formulations.El objetivo de este trabajo fue obtener microcápsulas de dos especies de aceite de sacha inchi (SIO), Plukenetia volubilis L. (SIVO) y Plukenetia huayllabambana L. (SIHO), utilizando diferentes biopolímeros como materiales de pared y la tecnología de secado por aspersión. Se analizaron tanto las características fisicoquímicas como la eficiencia de encapsulación, el tamaño de partícula, la morfología y la estabilidad oxidativa para seleccionar la mejor formulación que podría utilizarse como ingrediente en el desarrollo de alimentos funcionales. Se analizaron los aceites y cuatro formulaciones para cada ecotipo, usando diferentes agentes encapsulantes: maltodextrina (MD), goma Arábiga (AG), concentrado proteico de lactosuero (WPC) y almidón modificado HI-CAP®-100 (H). Las microcápsulas hechas con H presentaron la mayor estabilidad oxidativa y eficiencia de encapsulación en comparación con las formulaciones: AG; AG:MD o AG:MD:WPC

Analysis of Shot Noise at Finite Temperatures in Fractional Quantum Hall Edge States

We investigate shot noise at {\it finite temperatures} induced by the quasi-particle tunneling between fractional quantum Hall (FQH) edge states. The resulting Fano factor has the peak structure at a certain bias voltage. Such a structure indicates that quasi-particles are weakly {\it glued} due to thermal fluctuation. We show that the effect makes it possible to probe the difference of statistics between $\nu=1/5,{}2/5$ FQH states where quasi-particles have the same unit charge.Finally we propose a way to indirectly obtain statistical angle in hierarchical FQH states.Comment: 5 pages, 3 figure

EVALUATION OF TWO GENOTYPES OF GUINEA PIGS (Cavia porcellus) FED WITH CONCENTRATED AND EXCLUSION OF FORAGE

El estudio tuvo como objetivo evaluar los parámetros productivos y el porcentaje de grasa en la carcasa de dos genotipos de cuyes (Cavia porcellus) alimentados por nueve semanas con dos tipos de dieta. Se utilizó el diseño estadístico completamente al azar con arreglo factorial 2x2, teniendo como factores dos genotipos (Cieneguilla-UNALM y Perú-INIA) y dos tipos de dietas (dieta 1: alimento balanceado, forraje verde y agua; dieta 2: alimento balanceado más vitamina C y agua), y se evaluó el peso vivo final, ganancia de peso diaria, consumo de alimento, conversión alimenticia, peso y rendimiento de carcasa, y porcentaje de grasa y porcentaje de humedad en la carcasa. El peso vivo final, ganancia de peso, conversión alimenticia y peso de carcasa a las 12 semanas de edad en cuyes del genotipo Cieneguilla fue de 1266 g, 15.6 g/día, 3.14 y 878 g, respectivamente, en tanto que en los cuyes Perú fue de 1154 g, 13.6 g/día, 3.54 y 765 g, respectivamente (p<0.05). El factor genotipo no influyó en el consumo de alimento, rendimiento de carcasa ni el porcentaje de grasa y humedad en la carcasa. Asimismo, ni el tipo de dieta ni la interacción genotipo x tipo de alimentación fueron factores significativos en los parámetros productivos evaluados.The aim of the study was to evaluate the productive performance and percent of fat in the carcass of two guinea pig(Cavia porcellus) genotypes fed for nine weeks with two types of diets. A Randomized Complete Design with 2x2 factorial arrangements was used: two genotypes (Cieneguilla-UNALM and Peru-INIA) and two diets (diet 1: concentrate supplement, forage and water, and diet 2: concentrate supplement with vitamin C and water). The final body weight, daily weight gain, dry matter intake, feed conversion, carcass weight and yield, and fat and moisture percentage of the carcasses were evaluated. The final body weight, body weight gain, feed conversion and carcass weight at 12 weeks of age in Cieneguilla animals was 1266 g, 15.6 g/day, 3.14 and 878 g respectively whereas in Peru animals was 1154 g, 13.6 g/day, 3.54 and 765 g respectively (p<0.05). The genotype did not affect dry mater intake, carcass yield, or fat and moisture percentage. Moreover, neither the type of diet nor the interaction genotype x diet were significant factors affecting the parameters under evaluation

Electric-Field Tuning of Spin-Dependent Exciton-Exciton Interactions in Coupled Quantum Wells

We have shown experimentally that an electric field decreases the energy separation between the two components of a dense spin-polarized exciton gas in a coupled double quantum well, from a maximum splitting of $\sim 4$ meV to zero, at a field of $\sim$35 kV/cm. This decrease, due to the field-induced deformation of the exciton wavefunction, is explained by an existing calculation of the change in the spin-dependent exciton-exciton interaction with the electron-hole separation. However, a new theory that considers the modification of screening with that separation is needed to account for the observed dependence on excitation power of the individual energies of the two exciton components.Comment: 5 pages, 4 eps figures, RevTeX, Physical Review Letters (in press

Starch Yield Based on Physical Dimensions and Age of Sago Palm: A Mathematical Model

This study employed firefly algorithm (FA) to generate a mathematical model of sago palm’s potential starch yield based on the physical dimensions, namely, diameter breast height (DBH), palm height, and age. Three environmental conditions (i.e., dry, wet, and submerged) were taken into consideration in the modelling process using the general linear and nonlinear models. Moreover, the resulting models were assessed using sum of squared residuals (SSR) as FA’s fitness function and mean absolute percentage error (MAPE) for the models’ accuracy. Results show that general linear models are the best fit models for the sago palms growing in the three different environmental conditions with respect to the considered parameters. These models were used to quantitatively describe the underlying relationships between the starch yield with respect to the physical dimensions and age in order to determine the maximum potential starch yield of sago palm for the different environmental conditions. The models estimate that the maximum potential starch yield for dry, wet, and submerged environmental conditions are as follows: 0.75 m, 0.35 m, and 0.75 m for DBH, respectively; 10.5 m for palm height for all three; and 11.5 years, 15.5 years, and 15.5 years for age, respectively. These results will be able to aid farmers and potential investors in maximizing their sago starch produce. This will also help them as a guide for identifying harvestable sago palms which can be incorporated in their harvest plan