Frequency filters with OTA amplifiers

Práce je zaměřena na problematiku kmitočtových filtrů s OTA zesilovači. Analyzuje návrhy kmitočtových filtrů 2.řádu s OTA zesilovači a kmitočtové filtry vyšších řádů. Řeší návrh multifunkčního kmitočtového filtru 2.řádu s třemi OTA zesilovači v napěťovém režimu, s podporou počítačových metod návrhu a jeho realizaci. Stanovuje přenosové funkce navrženého filtru a simuluje jeho přenosové kmitočtové charakteristiky. Navržený kmitočtový filtru realizuje a experimentálně ověřuje jeho vlastnosti. Výsledky porovnává s teoreticky získanými hodnotami počítačovou simulací.Work is bent on problems frequency-selection filter with OTA amplifier. Analyses suggestions frequency-selection filter 2.order with OTA amplifier plus frequency-selection filter highers order. Smoothing - out proposal multifunction frequency-selection filter 2.order with by three OTA amplifier in suspense regime, with the support computer methods proposal plus his realization. Establishes temporary carrier function designed filter command plus malingers his temporary carrier frequency characteristics. Designed frequency-selection filter implements plus experimentally checks his characteristics. Record confront with abstractedly gained values computer malingering.

Biosynthesis and NMR-studies of a double transmembrane domain from the Y4 receptor, a human GPCR

The human Y4 receptor, a class A G-protein coupled receptor (GPCR) primarily targeted by the pancreatic polypeptide (PP), is involved in a large number of physiologically important functions. This paper investigates a Y4 receptor fragment (N-TM1-TM2) comprising the N-terminal domain, the first two transmembrane (TM) helices and the first extracellular loop followed by a (His)6 tag, and addresses synthetic problems encountered when recombinantly producing such fragments from GPCRs in Escherichia coli. Rigorous purification and usage of the optimized detergent mixture 28mM dodecylphosphocholine (DPC)/118mM% 1-palmitoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] (LPPG) resulted in high quality TROSY spectra indicating protein conformational homogeneity. Almost complete assignment of the backbone, including all TM residue resonances was obtained. Data on internal backbone dynamics revealed a high secondary structure content for N-TM1-TM2. Secondary chemical shifts and sequential amide proton nuclear Overhauser effects defined the TM helices. Interestingly, the properties of the N-terminal domain of this large fragment are highly similar to those determined on the isolated N-terminal domain in the presence of DPC micelle

Biosynthesis and NMR-studies of a double transmembrane domain from the Y4 receptor, a human GPCR

The human Y4 receptor, a class A G-protein coupled receptor (GPCR) primarily targeted by the pancreatic polypeptide (PP), is involved in a large number of physiologically important functions. This paper investigates a Y4 receptor fragment (N-TM1-TM2) comprising the N-terminal domain, the first two transmembrane (TM) helices and the first extracellular loop followed by a (His)6 tag, and addresses synthetic problems encountered when recombinantly producing such fragments from GPCRs in Escherichia coli. Rigorous purification and usage of the optimized detergent mixture 28 mM dodecylphosphocholine (DPC)/118 mM% 1-palmitoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] (LPPG) resulted in high quality TROSY spectra indicating protein conformational homogeneity. Almost complete assignment of the backbone, including all TM residue resonances was obtained. Data on internal backbone dynamics revealed a high secondary structure content for N-TM1-TM2. Secondary chemical shifts and sequential amide proton nuclear Overhauser effects defined the TM helices. Interestingly, the properties of the N-terminal domain of this large fragment are highly similar to those determined on the isolated N-terminal domain in the presence of DPC micelles

CO2 reduction with algae

Práce je zaměřena na proces kultivace řas a jejich využití pro snižování emisí oxidu uhličitého. Hlavním cílem práce je hmotnostní a tepelná bilance fotobioreaktoru a návrh řešení regulace teploty. V rámci práce byla vypracována rešerše, která se zabývá jednotlivými typy bioreaktorů a fotobioreaktorů, aktuální situací kolem klimatu a vlivu kultivace mikrořas na emise oxidu uhličitého. V práci je popsán model pro regulaci teploty a přenosu hmoty deskového fotobioreaktoru.The aim of this final thesis is the process of algae cultivation their use for carbon dioxid reduction. The main objective of this work is the mass and heat balance of the photobioreactor and the design of a temperature control system. Within the research work, an overview of certain types of bioreactors and photobioreactors, the current situation around the climate and the impact of the cultivation of algae on carbon dioxide emissions. The model for temperature control and mass transfer of a plate photobioreactor is created in this work.

Electrical properties of alternative liquids for electrical engineering

Diplomová práce obsahuje rozdělení elektroizolačních olejů, popis vlastností jednotlivých druhů a aktuální přehled o nových elektroizolačních kapalinách. Součástí práce je vysvětlení polarizace a vodivosti látky. V praktické části je porovnána změřená teplotní závislost složek komplexní permitivity a rezistvity několika složek vyšších mastných kyselin, rostlinných olejů a trafo oleje. Byly stanoveny a porovnány hodnoty průrazného napětí měřených izolačních kapalin.Electrical insulating liquids, organic esters, conductivity, dielectric, permittivity

Análisis del clima organizacional y su influencia en el desempeño laboral de la empresa Suvahi. periodo 2017

La presente investigación titulado “ANÁLISIS DEL CLIMA ORGANIZACIONAL Y SU INFLUENCIA EN EL DESEMPEÑO LABORAL DE LA EMPRESA SUVAHI. PERIODO 2017”; se planteó con el objetivo de determinar la relación entre el clima organizacional y el desempeño laboral en la empresa Suvahi S.A.C. Siendo un estudio de enfoque cuantitativo de tipo correlacional no experimental; de alcance de descriptivo, ya que el propósito fue describir lar variables y analizarlas en un momento dado. Para la obtención de información para esta investigación se aplicó una encuesta a los 28 trabajadores de la empresa Suvahi S.A.C. El cuestionario estuvo compuesto por intems, con una amplitud de escala de Likert (siempre, casi siempre, algunas veces, casi nunca, nunca). En cuanto a la recolección de datos, se aplicó un cuestionario para cada variable como son: El liderazgo, motivación, reciprocidad, y comunicación como factores que está relacionado con el clima organizacional, así mismo el reconocimiento de logros, ambiente físico, responsabilidad, trabajo en equipo como factores relacionados con el desempeño laboral. Para medir la correlación que existe entre estas dos variables, se utilizó el coeficiente de Spearmam donde se pretendió demostrar el tipo de relación. Donde se pudo concluir que la correlación es de 0.942, donde demuestra que existe una relación directa; positiva muy fuerte; es decir que a medida que se incrementa la relación en un mismo sentido, crece para ambas variables. Asimismo, la significatividad, es alta porque la evidencia estadística demuestra que los resultados presentan un menor a 0.01.Entonces no existe suficiente evidencia estadística para rechazar la relación, porque la p-valor <0.05.Tesi

Mutations affecting ligand specificity of the G-protein-coupled receptor for the Saccharomyces cerevisiae tridecapeptide pheromone

AbstractRandom mutations were generated in the G-protein-coupled receptor (Ste2p) for the tridecapeptide pheromone (α-factor) of Saccharomyces cerevisiae. These mutants were screened for variants that responded to antagonists. Because multiple mutations were detected in each mutant receptor recovered from the screen, site-directed mutagenesis was used to create single-site mutant receptors. Three receptors containing mutations F55V, S219P, and S259P were analyzed for their biological responses to various α-factor analogs and for their ligand binding profiles. Cells expressing each of the mutant receptors responded to α-factor as well as or better than wild-type cells in a growth arrest assay. In contrast, the binding of α-factor to the F55V and S219P mutant receptors was at least 10-fold reduced in comparison to wild-type receptor indicating a complex non-linear correlation between binding affinity and biological activity. Cells expressing mutant receptors responded to some normally inactive analogs in biological assays, despite the fact that these analogs had a low affinity for Ste2p. The analysis of these mutant receptors confirms previous findings that the first and sixth transmembrane regions of Ste2p are important for ligand interaction, ligand specificity, and/or receptor activation to initiate the signal transduction pathway. Changes in binding affinity of pheromone analogs to wild-type and mutant receptors indicate that residue 55 of Ste2p is involved with both ligand binding and signal transduction

A Paradigm for Peptide Hormone-GPCR Analyses

Work from our laboratories over the last 35 years that has focused on Ste2p, a G protein-coupled receptor (GPCR), and its tridecapeptide ligand α-factor is reviewed. Our work utilized the yeast Saccharomyces cerevisiae as a model system for understanding peptide-GPCR interactions. It explored the structure and function of synthetic α-factor analogs and biosynthetic receptor domains, as well as designed mutations of Ste2p. The results and conclusions are described using the nuclear magnetic resonance interrogation of synthetic Ste2p transmembrane domains (TMs), the fluorescence interrogation of agonist and antagonist binding, the biochemical crosslinking of peptide analogs to Ste2p, and the phenotypes of receptor mutants. We identified the ligand-binding domain in Ste2p, the functional assemblies of TMs, unexpected and interesting ligand analogs; gained insights into the bound α-factor structure; and unraveled the function and structures of various Ste2p domains, including the N-terminus, TMs, loops connecting the TMs, and the C-terminus. Our studies showed interactions between specific residues of Ste2p in an active state, but not resting state, and the effect of ligand activation on the dimerization of Ste2p. We show that, using a battery of different biochemical and genetic approaches, deep insight can be gained into the structure and conformational dynamics of GPCR-peptide interactions in the absence of a crystal structure