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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Mitochondriální cytochrom c oxidasa: inhibice kyanidem a vliv defektu asemblačního faktoru Surf1 / Mitochondrial cytochrome c oxidase: cyanide inhibition and role of assembly factor Surf1 defect

Nůsková, Hana January 2010 (has links)
The activity of mitochondrial cytochrome c oxidase (COX) can be affected by either exogenous or endogenous factors. The most efficient and in the environment abundant compound that inhibits COX is cyanide. The very frequent cause of COX deficiency in humans is represented by a defect in the SURF1 gene. The mechanism of cyanide inhibitory effect on COX as well as the conditions for its recovery are not yet fully explained. Three parameters of COX function, namely the transport of electrons (oxygen consumption), the transport of protons (mitochondrial membrane potential, m) and the enzyme affinity to oxygen (p50 value), were studied with regard to the inhibition by KCN and its reversal by pyruvate. The function of COX was analysed in intact isolated rat liver mitochondria, both within the respiratory chain and as a sole enzyme, using succinate or an artificial electron donor ascorbate + TMPD as a substrate. 250 M KCN completely inhibited both electron- and proton-transporting function of COX, and this inhibition was reversible as proved with washing of mitochondria. The addition of 60 mM pyruvate induced the maximal recovery of both parameters to 60 - 80 % of original values. Using KCN in the low concentration range up to 5 M, a profound, 30-fold decrease of COX affinity to oxygen was observed....
42

Inre fel på valsar / Internal defects in rolls

Skoglund, Thomas January 2008 (has links)
<p>Rapporten beskriver en undersökning rörande två olika typer av inre fel, centrumfel och ytnära fel, på valsar. Examensarbete för högskoleingenjörsexamen i maskinteknik (22.5p) vid Instutitionen för ingenjörsvetenskap, fysik och matematik, Karlstad Universitet. Utfört på uppdrag av Scana Steel Björneborg AB.</p><p>Scana Björneborg är en av Europas ledande producenter av tunga friformsmidda detaljer och har eget stålverk, egen smedja, värmebehandlingsanläggning och maskinpark. På Scana Björneborg gjuts göt av järnskrot, varpå de smids, värmebehandlas och maskinbearbetas till valsar. Efter maskinbearbetning kontrolleras valsarna med ultraljud för att hitta eventuella inre fel. Specifikationerna från kund för hur stora indikationer får vara är strama och stora kostnader uppstår i samband med reklamationer, kassationer, omarbeten och förseningar. Felen har blivit alltmer frekventa och Scana Björneborg har satt samman två projektgrupper för att få försöka få bukt på dem. Examensarbetet skall understödja båda dessa grupper och genom undersökningen skapa underlag för vidare beslut. Undersökningen delades in i tre olika moment:</p><p>* Statistik och information som kunde användas för att hitta eventuella samband och orsaker till de olika feltyperna samlades i en databas.</p><p>* Den samlade statistiken och informationen organiserades, förenklades och analyserades sedan med hjälp av programmet SIMCA, ett program gjort för multivariata analyser av stora datamängder. Eventuella samband granskades och analyserades därefter manuellt för att väga och gallra resultatet .</p><p>* Sex ytnära fel i tre olika detaljer öppnades upp för kartläggning av vilken typ av defekter det rörde sig om, och en metallografisk undersökning i ljus- och svepelektronmikroskop och analys av defekternas sammansättning gjordes.</p><p>SIMCA-analys av insamlad statistik med avseende på centrumfel och vidare granskning och analys av dess resultat antyder att hög smidesvikt, hög Vanadinhalt, stukning, hög nedsmidningsgrad och smidestid per ton i den följden är viktiga faktorer vid uppkomsten av centrumfel, och att en viss samverkan finns mellan dem.</p><p>SIMCA-analys av insamlad statistik med avseende på ytnära fel och vidare granskning och analys av dess resultat antyder att ett samband mellan valda parametrar och uppkomsten av ytnära fel inte går att hitta. Metoden bedöms olämplig för vidare undersökning av ytnära fel.</p><p>Den metallografiska undersökningen av öppnade ytnära defekter visade att samtliga sex defekter liknade varandra till utseende och sammansättning. Vanligaste beståndsdelarna i dessa inneslutningar var Aluminium tillsammans med förhöjda halter av Kol och Syre. Dessa ämnen är alla naturliga i stålet och därför bedöms inte de ytnära felen vara utifrån kommande.</p> / <p>The report describes an investigation concerning two types of internal defects, axis-centered defects and near-surface defects, in rolls. Thesis for bachelor’s degree in mechanical engineering (22.5p), at the institution for engineering, physics and mathematics, Karlstad University. Ordered by Scana Steel Björneborg AB.</p><p>Scana Steel Björneborg AB is one of Europe’s leading producers of heavy free-form forgings and has its own steel plant, forge, heating treatment facility and machine park. Scana Steel Björneborg AB casts ingots from iron scrap. The ingots are then forged, heat treated and machined into rolls. After the machining the rolls are tested with ultrasonic testing equipment to look for indications of internal defects. The specifications on how big the indications are allowed to be from the client are rigid and large costs come up because of reclamations, discarding, reworking and delays. The defects have become increasingly more frequent and Scana Steel Björneborg AB has put together two groups to try and get control over the problem. The thesis is meant to support the two groups by investigating the internal defects, and to create a platform to take further decisions from. The investigation was made up of three parts:</p><p>* Statistics and information that could be used to find connections and cause of the internal defects was gathered in a data base.</p><p>* The gathered statistics and information was organized, simplified and analyzed with SIMCA, a computer software made for multivariate analyzing of large amounts of information. The results of the SIMCA-simulation were then checked further manually to weigh and lay down the fairness of the results.</p><p>* Six near-surface defects in three parts were opened up to map the types of defects and a metallographic examination in optical microscope, scanning electron microscope and spectrometer analysis of the defects’ composition was made.</p><p>The SIMCA analysis of gathered statistics concerning axis-centered defects and later manual analysis of the results showed that high forging weight, high Vanadium content, high degree of forging and low forging-time per tonne all relate to the creation of axis-centered defects, and that some interaction is present between them.</p><p>The SIMCA analysis concerning near-surface defects showed that the chosen parameters do not relate with the creation of near-surface defects. The method is deemed unsuitable for further investigations.</p><p>The metallographic examination of the six near-surface defects showed that all six defects resemble each other in appearance and composition. The most common elements in these inclusions are Aluminum and heightened contents of Carbon and Oxygen. These elements are all naturally occurring elements in the steel and because of this the inclusions are not thought to be exogenous.</p>
43

Inre fel på valsar / Internal defects in rolls

Skoglund, Thomas January 2008 (has links)
Rapporten beskriver en undersökning rörande två olika typer av inre fel, centrumfel och ytnära fel, på valsar. Examensarbete för högskoleingenjörsexamen i maskinteknik (22.5p) vid Instutitionen för ingenjörsvetenskap, fysik och matematik, Karlstad Universitet. Utfört på uppdrag av Scana Steel Björneborg AB. Scana Björneborg är en av Europas ledande producenter av tunga friformsmidda detaljer och har eget stålverk, egen smedja, värmebehandlingsanläggning och maskinpark. På Scana Björneborg gjuts göt av järnskrot, varpå de smids, värmebehandlas och maskinbearbetas till valsar. Efter maskinbearbetning kontrolleras valsarna med ultraljud för att hitta eventuella inre fel. Specifikationerna från kund för hur stora indikationer får vara är strama och stora kostnader uppstår i samband med reklamationer, kassationer, omarbeten och förseningar. Felen har blivit alltmer frekventa och Scana Björneborg har satt samman två projektgrupper för att få försöka få bukt på dem. Examensarbetet skall understödja båda dessa grupper och genom undersökningen skapa underlag för vidare beslut. Undersökningen delades in i tre olika moment: * Statistik och information som kunde användas för att hitta eventuella samband och orsaker till de olika feltyperna samlades i en databas. * Den samlade statistiken och informationen organiserades, förenklades och analyserades sedan med hjälp av programmet SIMCA, ett program gjort för multivariata analyser av stora datamängder. Eventuella samband granskades och analyserades därefter manuellt för att väga och gallra resultatet . * Sex ytnära fel i tre olika detaljer öppnades upp för kartläggning av vilken typ av defekter det rörde sig om, och en metallografisk undersökning i ljus- och svepelektronmikroskop och analys av defekternas sammansättning gjordes. SIMCA-analys av insamlad statistik med avseende på centrumfel och vidare granskning och analys av dess resultat antyder att hög smidesvikt, hög Vanadinhalt, stukning, hög nedsmidningsgrad och smidestid per ton i den följden är viktiga faktorer vid uppkomsten av centrumfel, och att en viss samverkan finns mellan dem. SIMCA-analys av insamlad statistik med avseende på ytnära fel och vidare granskning och analys av dess resultat antyder att ett samband mellan valda parametrar och uppkomsten av ytnära fel inte går att hitta. Metoden bedöms olämplig för vidare undersökning av ytnära fel. Den metallografiska undersökningen av öppnade ytnära defekter visade att samtliga sex defekter liknade varandra till utseende och sammansättning. Vanligaste beståndsdelarna i dessa inneslutningar var Aluminium tillsammans med förhöjda halter av Kol och Syre. Dessa ämnen är alla naturliga i stålet och därför bedöms inte de ytnära felen vara utifrån kommande. / The report describes an investigation concerning two types of internal defects, axis-centered defects and near-surface defects, in rolls. Thesis for bachelor’s degree in mechanical engineering (22.5p), at the institution for engineering, physics and mathematics, Karlstad University. Ordered by Scana Steel Björneborg AB. Scana Steel Björneborg AB is one of Europe’s leading producers of heavy free-form forgings and has its own steel plant, forge, heating treatment facility and machine park. Scana Steel Björneborg AB casts ingots from iron scrap. The ingots are then forged, heat treated and machined into rolls. After the machining the rolls are tested with ultrasonic testing equipment to look for indications of internal defects. The specifications on how big the indications are allowed to be from the client are rigid and large costs come up because of reclamations, discarding, reworking and delays. The defects have become increasingly more frequent and Scana Steel Björneborg AB has put together two groups to try and get control over the problem. The thesis is meant to support the two groups by investigating the internal defects, and to create a platform to take further decisions from. The investigation was made up of three parts: * Statistics and information that could be used to find connections and cause of the internal defects was gathered in a data base. * The gathered statistics and information was organized, simplified and analyzed with SIMCA, a computer software made for multivariate analyzing of large amounts of information. The results of the SIMCA-simulation were then checked further manually to weigh and lay down the fairness of the results. * Six near-surface defects in three parts were opened up to map the types of defects and a metallographic examination in optical microscope, scanning electron microscope and spectrometer analysis of the defects’ composition was made. The SIMCA analysis of gathered statistics concerning axis-centered defects and later manual analysis of the results showed that high forging weight, high Vanadium content, high degree of forging and low forging-time per tonne all relate to the creation of axis-centered defects, and that some interaction is present between them. The SIMCA analysis concerning near-surface defects showed that the chosen parameters do not relate with the creation of near-surface defects. The method is deemed unsuitable for further investigations. The metallographic examination of the six near-surface defects showed that all six defects resemble each other in appearance and composition. The most common elements in these inclusions are Aluminum and heightened contents of Carbon and Oxygen. These elements are all naturally occurring elements in the steel and because of this the inclusions are not thought to be exogenous.
44

Klinische und kernspintomographische Ergebnisse nach Implantation von artifiziellen TruFit-Zylindern in die Entnahmedefekte bei der autologen Knorpel-Knochen-Transplantation / Clinical and MRI results after implantation of artificial TruFit cylinders in the defetcs of the donor site after autologous osteochondral transplantation

Voß, Maike 09 February 2011 (has links)
No description available.
45

Nové trendy v hojení chronických ran / New trends in healing chronic wounds

KREJSKOVÁ, Kamila January 2013 (has links)
Basic theoretical bases As a chronic wound is called a secondarily healing wound which despite adequate therapy does not tend to heal for a period of 6-9 weeks. The cause of the chronic wound occurrence and its transformation into an acute wound can be infection, influence of associated diseases, skin top layer microtraumatization or skin necrosis cavity. Among the most frequent types of chronic wounds there are aligned venous ulcerations, arterial rodent ulcers, decubitus ulcers and neuropathic rodent ulcers as a consequence of diabetes mellitus disease. Knowledge about wound healing has been deepened considerably in the last few years. The pharmaceutical industry introduces to the market continuously new means of phase wound healing and owing to new trends the classical treatment has nearly disappeared. Essay targets 1.To monitor nurse knowledge about new trends in chronic wound healing. 2.To determine what means of draping and bandaging materials are used in chronic wound treatment in practice and what means appear to be the most effective. 3.To find out if in practical terms there are conditions for nurses to use new trends in chronic wound healing and what constraints they meet in their endeavour to apply these trends. 4.To learn if patients with a non-healing wound are informed about new trends in chronic wound healing. 5.To learn if new trends in chronic wound healing are available for affected patients and in what extent they are used by them. 6.To determine if new trends in chronic wound healing improve life quality of patients with chronic wounds. Used methods The empirical part of the diploma work was processed with a tool of qualitative research inquiry. For data acquisition I chose the technique of semi-structured interview with respondents. For research inquiry I selected two groups of respondents. The first group of respondents was comprised of 10 nurses employed in Nemocnice České Budějovice, a.s. and in the other group there were 5 patients hospitalized in this facility. The interview findings were analysed and divided into categories. For clear arrangement there were created schemes to individual categories in XMind programme. The schemes are supplied with commentary and several quotations of the respondents. Findings From interview analyses it is clear that there is a certain influence of individuality. In the first part there is monitored nurse knowledge about modern trends in chronic wound healing. The conclusion of the research is that in all sections where interviewed nurses work chronic wounds are treated by the way of wet (phase) healing. I also found out that there are several therapeutic and draping materials suitable for all phases of chronic wound healing. There are also described a few practical problems which make effective care about chronic wounds difficult. In the second part there are mentioned particular defects in patient acquaintance with modern methods in wound healing and insufficient education by medical staff. There are also described all problems which deteriorate life quality of patients with chronic wounds. Conclusion The chronic wound healing methods have changed completely in the last few years. Pharmaceutical firms introduce to the market a lot of new materials facilitating very effective and comfortable care about wounds. However, this fact requires continuous education of medical staff participating in the chronic wound treatment. This brings positive results and finally decreases economic costs of care about patients with chronic wounds.
46

Influence of mesoscopic structures on single molecule dynamics in thin smectic liquid crystal films

Schulz, Benjamin, Täuber, Daniela, Schuster, Jörg, Baumgärtel, Thomas, von Borczyskowski, Christian 12 September 2013 (has links) (PDF)
Mesoscopic structures in liquids have an impact on the diffusion dynamics of the constituting molecules. Smectic 8CB liquid crystals on silicon wafers show the formation of mesoscopic structures on the μm scale at a film thickness of 200 nm. Depending on the kind of substrate (thermally grown or native SiOx), we observed the formation of focal conic domains (FCDs) and a new type of terraced holes, respectively. Dynamics are described via single perylene diimide tracer molecule tracking of translational diffusion and in the case of FCDs by a combination of translation and rotation detected via fluorescence correlation spectroscopy. Tailoring perylene diimide molecules such that the optical transition dipole moment follows the liquid crystal director allows mapping out FCDs and investigating the dynamics within a single FCD.
47

Skapa värde ur misstag : Genom DASIAS föreslås förbättringar i processen för hantering av avvikelser och kassationer / Gain from failure : Through DASIAS suggesting improvements in the process of handling defects and deviations

Strid, Magnus, Hagman Sturmhoefel, Johanna January 2021 (has links)
Denna deduktiva fallstudie har genomförts på företaget e-Component Sweden AB som tillverkar stål- och plåtdetaljer efter kundspecifikation. Företaget producerar huvudsakligen detaljer till den marknadsledande tiltrotatorn (grävmaskinens handled) från engcon. Studien avsåg att undersöka processen för hantering av avvikelser och kassationer. Det övergripande syftet var att, genom den relativt nya förbättringsmodellen DASIAS, studera en förbättringsmöjlighet med avseende på kvalitet genom att finna gap mellan nuläget och ett önskat nyläge. Därefter har lämpliga förbättringar samt en plan för implementering av förbättringarna föreslagits.  Studien har tillämpat de metoder, verktyg och analyser som DASIAS föreskriver. Datainhämtning har skett genom observationer, intervjuer och dokumentinsamling. Resultatet visar att en förbättringsmöjlighet finns och har identifierat resurserna; metod, mätningar, material, maskin, mission och management som orsaker till förbättringsmöjligheten. Vidare  visar studien att det genom en optimerad process för hanteringen av avvikelser och kassationer efter justerade rutiner och arbetssätt som skapar förutsättningar för att börja process- och kvalitetsleda, finns möjlighet att förebygga och genom ständiga förbättringar minimera avvikelser och kassationer i produktionen. Tidigare studier, den teoretiska referensramen och denna studies resultat tyder på att de konkreta förslag på tvärvetenskapliga åtgärder som utarbetats skulle ge positiva effekter på företagets kvalitet. Analysen visar att det önskade nyläget skulle föra företaget närmare uppställda kund- och intressentkrav. / This deductive case study has been carried out at the company e-Component Sweden AB, which manufactures steel- and sheet metal details, to customer specifications. The company mainly produces details for the market-leading tiltrotator (the excavators wrist) from engcon. The purpose of the study was to examine the process for handling defects and deviations from the main production. The overall aim was to, through the relatively new possibility- and improvement model DASIAS, study an opportunity for improvement with regard to quality by identifying a gap between the current procedure and a desired new procedure. Thereafter, appropriate improvements including a plan for implementing the improvements has been proposed.  The study has applied the tools and analyzing methods as prescribed by DASIAS. Data has been collected through observations, interviews and document collection. The study's result suggests that there is an opportunity for improvement and have identified the resources method, measurements, materials, machine, mission and management as reasons for the improvement opportunity. Further, the study suggests that through an optimized process for handling defects and deviations – following adjusted routines and working methods and creating conditions for implementing process and quality management, there is an opportunity to prevent and through continuous improvements minimize defects and deviations in the main production. Previous studies, the theoretical frame of reference and the results of this study suggest that the concrete interdisciplinary measures proposed would have a positive impact on the company’s overall quality. The analysis shows that the desired new situation would bring the company closer to customer- and stakeholder requirements.
48

Diagnosis of Pneumatic Cylinders Using Acoustic Emission Methods / Diagnosis of Pneumatic Cylinders Using Acoustic Emission Methods

Mahmoud, Houssam January 2019 (has links)
Tato práce se zabývá vývojem nového efektivního diagnostického postupu pro kontrolu funkce pneumatických válců pomocí metody akustické emise. Cílem práce bylo navrhnout a určit diagnostická kritéria pro hodnocení kvality vybraných typů pneumatických válců. Prvním krokem bylo nalezení typického akustického emisního signálu, který je spojen s určitým typem poškození ve válci využitím frekvenčního spektra signálu. Později byl tento parametr nahrazen parametrem RMS během sledování změn v průběhu testů. Na konkrétních válcích byl sledován vztah mezi akustickou emisí a různými typy defektů a byl představen nový přístup k určování těchto typů vad a jejich odlišením v signálu akustické emise. Druhý krok studie že neporušené a poškozené válce byly porovnávány tak, aby se zjistily výrazné rozdíly, které určují, zda je válec poškozen nebo nepoškozen. Několik nepoškozených válců bylo testováno akustickou emisí a následně v nich byly vytvořeny umělé vady. Signály z vysouvání a zasouvání pístu byly zaznamenány a analyzovány pomocí řady parametrů. Na základě časového zpoždění a normalizace RMS byly rozpoznány odezvy mezi poškozenými a nepoškozenými pneumatickými válci. Rozdíly byly zjištěny porovnáním maximální hodnoty RMS ze snímače upevněného na předním víku válce a snímače upevněného na zadním víku válce pro jeden cyklus. Poškozené a nepoškozené válce byly rozlišeny pomocí rozdílů energetických hodnot přítomných v signálech z obou snímačů v závislosti na zdvihu pístu. Konečné vyhodnocení válce bylo určeno výpočtem celkové hodnoty RMS. Ve třetím kroku experimentu byly válce postupně zatěžovány různými závažími ve svislém směru. Signály akustické emise byly zaznamenány z vysouvání a zasouvání pístu a poté analyzovány. Časové zpoždění se vypočítává z digitálního vstupu a začátku pohybu pístu. Energie signálu a RMS akustické emise porovnávají různé reakce v poškozených a nepoškozených pneumatických válcích s a bez zatížení. Výsledky testu ukázaly lineární vztah mezi křivkou RMS a zatížením. Defekty ovlivňují vztah mezi aplikovaným zatížením a zaznamenaným signálem snímačů.
49

Dlouhodobé sledování parametrů fotovoltaických panelů / Long-term monitoring of parameters of photovoltaic modules

Kladiva, Roman January 2013 (has links)
This thesis deals with the influence of degradation mechanisms to change the parameters of photovoltaic panels. The aim of the study was the long-term monitoring of selected solar modules, comparing their parameters with measurements from previous years and the evaluation of degradation mechanisms on their properties. The theoretical part is focused on the description of the monitored parameters and defects Panel, are discussed measuring methods by which the modules were monitored. Experimental part then consists of measuring modules individual test methods. The measured values were subsequently constructed graphical dependence, and the results were compared with measurements from previous years. The last part of the thesis is devoted to evaluation of the degradation of PV modules.
50

Informovanost sester o možnostech využití vlhkého hojení ran v neonatologii. / Knowledge of nurses about posibilities of using moist wound healing in neonatology.

Konečná, Veronika January 2014 (has links)
This thesis deals with nursing care of skin defects using a wet therapy in neonatology. The first section summarizes information related to preterm infants, the development of the individual layers of the skin in the embryonic period. It lists the types of skin defects which the neonatolgy nurse may frequently encounter at the department with including a list of modern therapeutic coverage that can be used. It lists a brief history of wound healing too, focusing just on the development of the wet therapy . Furthermore is marginally discussed the evaluation and documentation of damage to the skin wound. For interest, the thesis mentions a case reportof the preterm newborn with the necrosis of the lower limb, accompanied by commentaries of the alternative treatment for this type of skin damage from my own experience. The second part is assessing the awareness of the nurses in the modern methods of the healing. The priority is the mapping of the experience in using the wet therapy through the quantitative research, which is mediated by an anonymous questionnaire. The main goal of the research is to determine the awareness of the nurses from the neonatology intensive care unit, resuscitation and intermediate care in the nursing of the skin defects using a wet therapy. For this purpose the chosen method...

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