Effects of antiferromagnetic planes on the superconducting properties of multilayered high-Tc cuprates

We propose a mechanism for high critical temperature (T_c) in the coexistent phase of superconducting- (SC) and antiferromagnetic (AF) CuO_2 planes in multilayered cuprates. The Josephson coupling between the SC planes separated by an AF insulator (Mott insulator) is calculated perturbatively up to the fourth order in terms of the hopping integral between adjacent CuO_2 planes. It is shown that the AF exchange splitting in the AF plane suppresses the so-called pi-Josephson coupling, and the long-ranged 0-Josephson coupling leads to coexistence with a rather high value of T_c.Comment: 4 pages including 4 figure

Absolute identification by relative judgment

In unidimensional absolute identification tasks, participants identify stimuli that vary along a single dimension. Performance is surprisingly poor compared with discrimination of the same stimuli. Existing models assume that identification is achieved using long-term representations of absolute magnitudes. The authors propose an alternative relative judgment model (RJM) in which the elemental perceptual units are representations of the differences between current and previous stimuli. These differences are used, together with the previous feedback, to respond. Without using long-term representations of absolute magnitudes, the RJM accounts for (a) information transmission limits, (b) bowed serial position effects, and (c) sequential effects, where responses are biased toward immediately preceding stimuli but away from more distant stimuli (assimilation and contrast)

Chitosan-Cellulose Composite for Wound Dressing Material. Part 2. Antimicrobial Activity, Blood Absorption Ability, and Biocompatibility

Chitosan (CS), a polysaccharide derived from chitin, the second most abundant polysaccharide, is widely used in the medical world because of its natural and nontoxic properties and its innate ability for antibacterial and hemostasis effects. In this study, the novel composites containing CS and cellulose (CEL) (i.e., [CEL + CS]), which we have previously synthesized using a green and totally recyclable method, were investigated for their antimicrobial activity, absorption of anticoagulated whole blood, anti-inflammatory activity through the reduction of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and the biocompatibility with human fibroblasts. The [CEL + CS] composites were found to inhibit the growth of both Gram positive and negative micro-organisms. For examples, the regenerated 100% lyophilized chitosan material was found to reduce growth of Escherichia coli (ATCC 8739 and vancomycin resistant Enterococcus faecalis (ATCC 51299) by 78, 36, and 64%, respectively. The composites are nontoxic to fibroblasts; that is, fibroblasts, which are critical to the formation of connective tissue matrix were found to grow and proliferate in the presence of the composites. They effectively absorb blood, and at the same rate and volume as commercially available wound dressings. The composites, in both air-dried and lyophilized forms, significantly inhibit the production of TNF-α and IL-6 by stimulated macrophages. These results clearly indicate that the biodegradable, biocompatible and nontoxic [CEL + CS] composites, particularly those dried by lyophilizing, can be effectively used as a material in wound dressings

Development and Morphology of the Ventricular Outflow Tracts.

It is customary, at the current time, to consider many, if not most, of the lesions involving the ventricular outflow tract in terms of conotruncal malformations. This reflects the introduction, in the early 1940s, of the terms conus and truncus to describe the components of the developing outflow tract. The definitive outflow tracts in the postnatal heart, however, possess three, rather than two, components. These are the intrapericardial arterial trunks, the arterial roots, and the subvalvar ventricular outflow tracts. Congenital lesions afflicting the arterial roots, however, are not currently considered to be conotruncal malformations. This suggests a lack of logic in the description of cardiac development and its use as a means of categorizing congenital malformations. It is our belief that the developing outflow tract, like the postnatal outflow tracts, can readily be described in tripartite fashion, with its distal, intermediate, and proximal components forming the primordiums of the postnatal parts. In this review, we present evidence obtained from developing mice and human hearts to substantiate this notion. We show that the outflow tract, initially with a common lumen, is divided into its aortic and pulmonary components by a combination of an aortopulmonary septum derived from the dorsal wall of the aortic sac and outflow tract cushions that spiral through its intermediate and proximal components. These embryonic septal structures, however, subsequently lose their septal functions as the outflow tracts develop their own discrete walls. We then compare the developmental findings with the anatomic arrangements seen postnatally in the normal human heart. We show how correlations with the embryologic findings permit logical analysis of the congenital lesions involving the outflow tracts

Active Fail-Safe Micro-Array Flow Control for Advanced Embedded Propulsion Systems

The primary objective of this research effort was to develop and analytically demonstrate enhanced first generation active "fail-safe" hybrid flow-control techniques to simultaneously manage the boundary layer on the vehicle fore-body and to control the secondary flow generated within modern serpentine or embedded inlet S-duct configurations. The enhanced first-generation technique focused on both micro-vanes and micro-ramps highly-integrated with micro -jets to provide nonlinear augmentation for the "strength' or effectiveness of highly-integrated flow control systems. The study focused on the micro -jet mass flow ratio (Wjet/Waip) range from 0.10 to 0.30 percent and jet total pressure ratios (Pjet/Po) from 1.0 to 3.0. The engine bleed airflow range under study represents about a 10 fold decrease in micro -jet airflow than previously required. Therefore, by pre-conditioning, or injecting a very small amount of high-pressure jet flow into the vortex generated by the micro-vane and/or micro-ramp, active flow control is achieved and substantial augmentation of the controlling flow is realized

Hall effect in strongly correlated low dimensional systems

We investigate the Hall effect in a quasi one-dimensional system made of weakly coupled Luttinger Liquids at half filling. Using a memory function approach, we compute the Hall coefficient as a function of temperature and frequency in the presence of umklapp scattering. We find a power-law correction to the free-fermion value (band value), with an exponent depending on the Luttinger parameter $K_{\rho}$. At high enough temperature or frequency the Hall coefficient approaches the band value.Comment: 7 pages, 3 figure

Neutrino Factory Designs and R&D

European, Japanese, and US Neutrino Factory designs are presented. The main R&D issues, and the associated R&D programs, are discussed.Comment: Talk presented at the XXth International Conference on Neutrino Physics and Astrophysics, May 25-30, 2002, Munich, Germany. 10 pages, 12 figure

Implementación de mejoras a la atención al cliente para optimizar la calidad de servicio en una empresa de casino y juegos de azar - Lima, 2022

Este trabajo de investigación tuvo como propósito implementar un plan de mejoras la atención al cliente para optimizar la calidad de servicio en una empresa de casino y juegos de azar ubicada en la ciudad de Lima, a partir de la situación inicial detectada en la organización en la que existían obstáculos que afectan la satisfacción de los clientes: a) falta de conocimiento en cuanto a técnicas de atención al cliente; (b) ausencia de planes de capacitación en el área de calidad de servicio y (c) falta de medición de la satisfacción del cliente. Para superar estas dificultades se crearon acciones cuyos lineamientos principales fueron: a) un plan general del programa de calidad de servicio; (b) y formación de líderes en servicio y capacitación al personal y (c) evaluación y control de resultados del programa. Se concluyó que, una vez implementada las acciones, los atributos que observaron los mejores cambios en la percepción de los clientes fue la capacidad de respuesta, la empatía por parte de los trabajadores y la fiabilidad en el servicio. En consecuencia, la disposición de excelente calidad de servicio a través de las interacciones entre los jugadores de máquinas tragamonedas y el personal de primera línea puede servir como una fuente clave de retención de clientes y generación de ingresos, así como la creación de una propuesta de valor diferenciadora para los clientes.The purpose of this research work was to implement a customer service improvement plan to optimize the quality of service in a casino and gambling company located in the city of Lima, based on the initial situation detected in the organization in which there were obstacles that affect customer satisfaction: a) lack of knowledge regarding customer service techniques; (b) absence of training plans in quality of service and (c) lack of measurement of customer satisfaction. To overcome these difficulties, actions were created whose main guidelines were a) a general plan of the service quality program; (b) and in- service leadership training and staff training and (c) evaluation and monitoring of program outcomes. It was concluded that, once the actions were implemented, the attributes that observed the best changes in customer perception were responsiveness, empathy on the part of workers and reliability in the service. Consequently, the provision of excellent quality of service through interactions between slot machine players and frontline staff can serve as a key source of customer retention and revenue generation, as well as creating a differentiating value proposition for customers

Compromiso organizacional en los colaboradores de una empresa retail - ciudad de Chiclayo 2016

La presente investigación tuvo como objetivo evaluar el nivel de compromiso organizacional en los colaboradores de la empresa retail Saga Falabella S.A. en la cuidad de Chiclayo, el diseño utilizado fue descriptivo. La población estuvo conformada por 230 colaboradores y con una muestra de 50 colaboradores. El instrumento empleado fue el cuestionario de Compromiso Organizacional de Meyer y Allen. Dentro de los hallazgos más relevantes encontramos que, en el compromiso afectivo, los resultados se aprecia que, el 23% no están de acuerdo con el compromiso afectivo, podemos determinar que existe poco apego emocional, identificación e involucramiento del colaborador con la organización. En cuanto al compromiso continuo, se observa en los resultados que el 32% se encuentran indecisos, por esta razón se presume que los colaboradores no se están sintiendo vinculados con la institución por lo se cree que es posible que no han invertido mucho tiempo, dinero, esfuerzo y no se sabría si esto implicaría perderlo todo y por último que, los colaboradores de la empresa retail Saga Falabella de la Ciudad de Chiclayo muestra que el 36% se encuentran indecisos y en desacuerdo, por esta razón se presume que los colaboradores no asumen aun una lealtad de permanecía y un sentimiento de obligación moral del colaborador de seguir dentro de la organización

Decay rate estimations for linear quadratic optimal regulators

Let $u(t)=-Fx(t)$ be the optimal control of the open-loop system $x'(t)=Ax(t)+Bu(t)$ in a linear quadratic optimization problem. By using different complex variable arguments, we give several lower and upper estimates of the exponential decay rate of the closed-loop system $x'(t)=(A-BF)x(t)$. Main attention is given to the case of a skew-Hermitian matrix $A$. Given an operator $A$, for a class of cases, we find a matrix $B$ that provides an almost optimal decay rate. We show how our results can be applied to the problem of optimizing the decay rate for a large finite collection of control systems $(A, B_j)$, $j=1, \dots, N$, and illustrate this on an example of a concrete mechanical system. At the end of the article, we pose several questions concerning the decay rates in the context of linear quadratic optimization and in a more general context of the pole placement problem.Comment: 25 pages, 1 figur