96 research outputs found

    Heat trace and heat content asymptotics for Schrodinger Operators of stable processes/fractional Laplacians

    Get PDF
    Let V be a bounded and integrable potential over Rd and 0 \u3c α ≤ 2. We show the existence of an asymptotic expansion by means of Fourier Transform techniques and probabilistic methods for the following quantities [special characters omitted] and [special characters omitted] as t ↓ 0. These quantities are called the heat trace and heat content in Rd with respect to V, respectively. Here, p((α)/ t)(x, y) and p( HV/t)(x, y) denote, respectively, the heat kernels of the heat semigroups with infinitesimal generators given by (-Δ)(α/2) and HV = (-Δ)(α/2) + V. The former operator is known as the fractional Laplacian whereas the latter one is known as the fractional Schrödinger Operator. ^ The study of the small time behaviour of the above quantities is motivated by the asymptotic expansion as t ↓ 0 of the following spectral functions for smooth bounded domains Ω ⊂ R d, [special characters omitted] where p(Ω,α/ t)(x, y) is the transition density of a stable process killed upon exiting Ω. ^ The function Z((α)/Ω)/)(t) is known as the heat trace and a second order expansion is provided in [6] for all 0 \u3c α ≤ 2 forR-smooth boundary domains. In [5] the result is extended to bounded domains with Lipschitz boundary. As for the spectral function Q((α)/Ω)( t), it is called the spectral heat content and has only been widely studied for the Brownian motion case. In fact, a third order asymptotic expansion is provided in [12] for α = 2. In this work, we will state a conjecture about the second order small time expansion. These expansions differ accordingly to the ranges 1 \u3c α \u3c 2, α = 1 and 0 \u3c α \u3c 1

    Sintesis de derivados isoxazolil quinolinicos y su actividad biologica

    Get PDF
    48 p.Sabidas, son las variadas propiedades que presentan tanto los isoxazoles, como las quinolinas en varios ámbitos hoy en día; Presentan grandes actividades a nivel de antiagregante plaquetario, antifúngicos, inhibidores de enzimas, etc. Utilizando la técnica de síntesis de varios pasos en un sólo reactor (one-pot) se pretende obtener una serie de compuestos isoxazólicos que posean en común un radical nitro en su estructura, en distintas posiciones, los cuales serán previamente hidrogenados formando un grupo amino, con el fin de obtener aminas, precursores necesarios para realizar la cicloadición imino Diels-Alder generando así derivados isoxazolil-quinolínicos, todo esto usando ultrasonido y microondas, para lograr el mayor rendimiento posible. A pesar de que esta técnica de síntesis es bien conocida y estudiada, y que su uso está considerablemente distribuido en el mundo de la síntesis química, no existen registros de la existencia de derivados isoxazolil-quinolínicos tanto naturales como sintéticos. Tomando en cuenta las propiedades farmacéuticas de los compuestos de la familia de las quinolínas e isoxazoles se pretende medir una posible actividad biológica y ver como al formar esta fusión, estos, son capaz de potenciarse para lograr mejores resultados que por si solos

    Medicion de los valores en el trabajo y la vida de los Carabineros de la Provincia de Nuble

    Get PDF
    116 p.Este Proyecto mide los valores del trabajo y la vida de los Carabineros de la Provincia de Nuble. Se utilizo un cuestionario de valores debidamente validado, adaptado del formato usado en variados estudios de la Universidad de Río de Janeiro y en investigaciones internacionales de catheter transcultural, realizadas con la finalidad de estudiar los valores y la motivación a nivel mundial. El muestreo de la investigación es de catheter estratificado aproporcional, con separación de oficiales y no oficiales. El instrumento se aplico a 144 Carabineros, calculándose las medias y desviaciones estándar de los distintos valores que midió el cuestionario, en forma posterior se rankearon estos aspectos para el total de la muestra, los oficiales, los no oficiales y por grupos de edad. En general, los valores mejor rankeados de la vida son : ser saludable, felicidad y amor. En el trabajo los mas importantes son: la estabilidad laboral, ser responsable por las actividades del trabajo y la prevención de accidentes en el trabajo. Los valores con menor importancia en la vida corresponden a ser rico, reconocimiento por lo hecho y hacer cosas interesantes. Al igual en el trabajo, los con peor ranking corresponden a ser independiente en el trabajo, recibir un salario alto y el reconocimiento por el desempeño. Los resultados de la investigación, arrojan diferencias mayores respecto a los valores de los distintos grupos de edad, que los rangos o niveles jerárquicos. El estudio permitirá aumentar y complementar la información sobre valores en Chile. Aportando mayores datos a investigaciones de catheter Internacional

    Editing interchanges Ostravska x Bedrichovicka, Brno

    Get PDF
    Bakalářská práce se zabývá návrhem úpravy úrovňové části mimoúrovňové kosodélné křižovatky v městské části Brno-Slatina. Na křižovatce se kříží silnice I/50 Ostravská a silnice II. třídy Bedřichovická. Jejím hlavním problémem je vysoká intenzita vozidel v křižném bodě mimoúrovňové křižovatky. Cílem práce je návrh úpravy křižovatky s primárním cílem odstranění křižných bodů na křižovatce a zlepšení křižovatkových pohybů s důrazem na bezpečnost vozidel i chodců. Práce dále řeší návrh chodníků, míst pro přecházení a bezbariérových úprav pro chodce. Výsledná úprava má v konečném důsledku zjednodušit pohyb jak chodců tak i motorových vozidel a zvýšit jejich bezpečnost. Součástí práce bylo provedeno ruční měření intenzit dopravy, které bylo následně vyhodnoceno a podle něj byly navrženy úpravy řešené křižovatky.This thesis deals with the proposal of level of Rhombo flyover junction in Brno- Slatina . At the junction with the road crosses the I/50 Ostravská and roads II class Bedřichovická. Its main problem is the high intensity of vehicles cross point interchanges . The aim is to draft amendment to the intersection with the primary aim of removing cross points at the intersection and interchange improvements movements with emphasis on the safety of vehicles and pedestrians . The work deals draft sidewalks, places for crossing a barrier adaptations for pedestrians . The resulting finish has ultimately simplify movement of both pedestrians and motor vehicles and improve their safety. Part of the work was done manual measurement of traffic volumes , which were subsequently evaluated and according to him, were proposed modifications designed intersection.

    Double acute appendicitis: cecal and epiploic; literature review of a case report

    Get PDF
    Acute cecal appendicitis and appendagitis are two entities due to the inflammation of the cecal and epiploic appendix respectively. A case of a 34-year-old woman is presented, who is admitted for abdominal pain. Initial blood test and ultrasonography were not conclusive, subsequently with clinical deterioration, surgical intervention was required which noted acute appendicitis and appendicitis that were removed. This is an extremely unusual case, since the simultaneous presentation of these two entities has not been widely described and demonstrates the importance of exploring the abdominal and pelvic cavity in patients with suspected diagnosis of acute appendicitis

    Knowledge of Latin American Obstetricians and Gynecologists regarding Heavy Menstrual Bleeding

    Get PDF
    Background. Heavy menstrual bleeding (HMB) is a common gynecological complaint affecting quality of life. Objectives. To assess knowledge on diagnosis and treatments of HMB of Latin American (LA) obstetricians and gynecologists (OBGYNs). Methods. A survey was conducted during a scientific meeting, organized to provide updated information on topics of reproductive medicine to OBGYNs from 12 LA countries who were invited to respond to a multiple-choice questionnaire. Results. Of the 210 OBGYNs participating in the survey, from 169 (80.4%) to 203 (96.7%) answered the questions. Most respondents (80%) gave accurate answers regarding the amount of blood loss which defines HMB, underreported the proportion of women who consulted due to HMB, and were aware that the use of combined oral contraceptives (COCs) with ethynyl estradiol is not an adequate treatment in women with HMB. Female OBGYNs and those who worked in the private sector were more prone to report a higher possibility of improvement of HMB with a COC that contained estradiol valerate and dienogest or with a levonorgestrel-releasing intrauterine system. Conclusions. In general, the respondents were aware of the importance of HMB in gynecological practice and of the new medical treatments and underreported the proportion of women who consulted due to HMB

    Intrathyroid parathyroid adenoma: report of two cases and literature review

    Get PDF
    Approximately 80% of patients with primary hyperparathyroidism have a parathyroid adenoma, with surgery being the only definitive treatment. Sometimes in surgery there is difficulty in identifying the pathological parathyroid gland at which time the possibility of ectopic parathyroid should be considered. We present two cases of patients which after hemithyroidectomy histopathological report, reported intrathyroid parathyroid adenoma. Intrathyroid parathyroid adenomas are an infrequent presentation of parathyroid adenomas that require high clinical suspicion if they are not detected by imaging studies in the preoperative period
    corecore