Hydrogen bonds and asymmetrical heat diffusion in a-Helices. A Computational Analysis

In this work, we report the heat rectifying capability of a-helices. Using molecular dynamics simulations we show an increased thermal diffusivity in the C-Terminal to N-Terminal direction of propagation. The origin of this effect seems to be a function of the particular orientation of the hydrogen bonds stabilizing these a-helices. Our results may be relevant for the design of thermal rectification devices for materials science and lend support to the role of normal length hydrogen bonds in the asymmetrical energy flow in proteins

Generación del canal pilot en un enlace forward de un sistema cdma utilizando dsp

En sistemas de comunicación personal (PCS) y celular basados en Acceso Múltiple por División de Código (CDMA), se hace uso de una señal Piloto en el enlace Forward para la sincronización, handoff, localización de posición, mantener ortogonalidad entre estaciones base y detección coherente. Esta tesis esta basada en el sistema CDMA y sus capacidades, y se enfoca en la implementación de un canal Piloto utilizando una plataforma DSP C6000 de Texas Instruments, lo que involucra generación de Códigos Walsh, Códigos Pseudoaleatorios y la etapa de Filtrado. Este documento también brinda al lector un acercamiento para entender los principios del procesamiento en tiempo real utilizando DSP, diseño de sistemas, consideraciones de implementación, aplicaciones del mundo real, así como también algunos ejemplos con DSP utilizando MATLAB, Simulink, Code Composer Studio y el TMS320C6416, en otras palabras esta es una tesis practica sobre CDMA y plataformas DSP

On the role of short and strong hydrogen bonds on the mechanism of action of a model chymotrypsine active site

The electronic properties of a chemical model that mimics the His-57 ••• Asp-102 catalytic residues of α-chymotrypsine during the transition from normal hydrogen bond to short and strong hydrogen-bond regimes are presented. The results suggest that upon a global external stimulus induced by compression, the system response is the transfer of the nucleophilic reactivity from the model Asp-102 moiety toward the model His-57 fragment in the hydrogen-bonded complex. In this way, the catalytic effect may be consistently explained on the basis of a pair site reactivity model framed on the second-order static density response function. © 2009 American Chemical Society

First report of the simultaneous occurrence of choroid plexus papilloma and meningioma in a dog

A 7-year-old spayed female English Cocker Spaniel was examined because of a 1-week history of lethargy, stumbling over objects and circling, and the presence of two tonic-clonic generalised seizures two days before presentation. The neurological signs suggested a lesion involving the right forebrain. Computed tomography revealed the presence of two intracranial masses, one located inside the right lateral ventricle and the other located in the right frontal lobe attached to the falx cerebri. Because of the poor prognosis, the owner refused to continue with the therapy and the dog was euthanised. On postmortem examination one mass was diagnosed histologically as a meningioma and the other as a papilloma of the choroid plexus. Information in the veterinary literature on multiple malignancies affecting the central nervous system is very limited. To the best of the authors’ knowledge, the association of meningioma and choroid plexus papilloma has never been reported either in the human or in the veterinary medical literature

Use of Adjunctive Therapy in Acute Kawasaki Disease in Latin America.

Objective: To characterize the use of adjunctive therapy in Kawasaki disease (KD) in Latin America. Methods: The study included 1,418 patients from the Latin American KD Network (REKAMLATINA) treated for KD between January 1, 2009, and May 31, 2017. Results: Of these patients, 1,152 received only a single dose of IVIG, and 266 received additional treatment. Age at onset was similar in both groups (median 2 vs. 2.2 years, respectively). The majority of patients were male (58 vs. 63.9%) and were hospitalized with the first 10 days of fever (85.1 vs. 84.2%). The most common adjunctive therapy administered was steroids for IVIG-resistance, followed by additional doses of IVIG. The use of biologics such as infliximab was limited. KD patients who received adjunctive therapy were more likely to have a lower platelet count and albumin level as well as a higher Z score of the coronary arteries. Conclusion: This is the first report of adjunctive therapies for KD across Latin America. IVIG continues to be the initial and resistance treatment, however, steroids are also used and to a lesser extent, biological therapy such as infliximab. Future studies should address the barriers to therapy in children with acute KD throughout Latin America