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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.
81

Improving venous blood specimen collection practices : method development and evaluation of an educational intervention program / Metoder för förbättrad venprovtagning : utvärdering av ett utbildningsprogram

Bölenius, Karin January 2014 (has links)
Background: About 60%–80% of decisions regarding diagnosis and treatment are based on laboratory test results. Low adherence to venous blood specimen collection (VBSC) guidelines may lead to erroneous or delayed test results, causing patient harm and high healthcare costs. Educational intervention programs (EIPs) to update, improve and sustain VBSC practices are seldom evaluated. After testing a self-reported venous blood sampling questionnaire, the overall aim of this thesis was to evaluate the impact of a large-scale EIP on healthcare personnel’s VBSC practices. Methods: The study settings were primary healthcare centres (PHCs) in northern Sweden. Participants were VBSC personnel. Data consisted of a VBSC questionnaire of self-reported practices, records of low-level haemolysis index in serum samples (specimen quality indicator), and interviews reflecting VBSC practices. First, experts on questionnaires and VBSC were consulted, and test-retest statistics were used when testing the VBSC questionnaire for validity and reliability. Thereafter, we evaluated the impact of a short, large-scale EIP with a before-after approach comparing self-reported VBSC questionnaire of two county councils. The personnel of the county councils (n = 61 PHCs) were divided into an intervention group (n = 84) and a corresponding control group (n = 79). In order to test changes in blood specimen quality we monitored haemolysis in serum samples (2008, n = 6652 samples and 2010, n = 6121 samples) from 11 PHCs. Finally, 30 VBSC personnel from 10 PHCs reported their experiences. The interview questions were open-ended with reflective elements and the interviews were analysed by qualitative content analysis. Results: The VBSC questionnaire was found to be valid and could be used to identify risk of errors (near misses) and evaluate the impact of an EIP emphasising VBSC guideline adherence. The intervention group demonstrated several significant improvements in self-reported practices after the EIP, such as information search, patient rest, test request management, patient identification, release of venous stasis, and test tube labelling. The control group showed no significant improvements. In total, PHCs showed minor differences in blood specimen quality. Interviews summarized VBSC personnel experiences in the overall theme: education opened up opportunities for reflection about safety.   Conclusion: This thesis is, to our knowledge, the first to evaluate the impacts of a large-scale EIP on VBSC practices. The VBSC questionnaire and monitoring for low-level haemolysis reflected VBSC practices. The frequently occurring near-miss markers made it possible to compare and benchmark VBSC practices down to the healthcare unit and hospital ward. The short, general EIP opened up opportunities for reflection about safety and improved VBSC practices in PHCs with larger deviations from guidelines. EIPs that provide time for reflection and discussion could improve VBSC further. Directed EIPs focused on specific VBSC flaws might be more effective for some near misses in VBSC practices, while some near misses must be changed at a different level in the system. Clinical relevance: Our results indicate that monitoring and counteracting the near misses in VBSC practices is a well-functioning preventive action. We propose that the VBSC monitoring instruments (VBSC questionnaire & haemolysis index) we used and the EIP strategy proposed should be tested in additional countries with different healthcare settings. It is suggested that a national program intended to identify near misses and prevent VBSC errors be developed in the healthcare system. General e-learning programs may be cheaper than, and as effective as, the EIP program and may be performed everywhere and any time. Systematic planning, useful for reflection and with focus on the specific elements in a skill, together with VBSC guidelines, could probably increase improvements. Our studies have led to deeper and extended knowledge of the impact of an EIP on VBSC practices. Our results can be used when considering future VBSC practice interventions. Using a model for practical skills in nursing to describe VBSC in a more holistic and less technical way might highlight VBSC as a practical nursing skill. / Bakgrund: Av kliniska beslut angående diagnostik och behandling baseras 60%–80% på laboratorieresultat. Därför är det helt nödvändigt att laboratorieresultat är tillförlitliga. Låg följsamhet till provtagnings anvisningar kan leda till felaktiga och fördröjda analysresultat, förorsaka skada och lidande för patienter och utgöra en stor kostnad för hälso- och sjukvården. Felaktiga provsvar beror till stor del på felaktig provtagning och provhantering och går oftast att undvika. Interventioner som avser att uppdatera och säkra korrekt venprovtagning kan leda till förbättringar men genomförda interventioner har sällan utvärderats. Efter att en enkät för självrapporterad venprovtagning testats för validitet och reliabilitet genomfördes ett omfattande interventionsprogram som utvärderades med hjälp av den testade enkäten och andra utvärderingsmått. Det övergripande syftet var att utvärdera i vilken utsträckning interventionsprogrammet påverkade provtagande personals praktiska utförande av venprovtagning. Metoder: Studierna i denna avhandling omfattade provtagande personal vid hälsocentraler i norra Sverige. För datainsamling användes en enkät som mäter självrapporterad venprovtagning, förekomst av låggradig hemolys (indikator på blodprovets kvalitet) och intervjuer. Initialt testades enkätens förmåga att mäta vad som avsetts (validitet) och testades enkätens förmåga att vid upprepade mätningar vara tillräckligt stabil (reliabilitet) för att användas i interventionsstudier. Därefter utvärderades ett kort men storskaligt interventionsprogram i preanalys inkluderande venprovtagning med före och efter mätningar. Vi jämförde provtagande personal från två landsting vid 61 hälsocentraler. Landstingens personal delades upp i en interventionsgrupp (n=84) och en motsvarande kontrollgrupp (n = 79). För att mäta kvaliteten av blodproverna extraherades uppgifter om hemolys i serumprover (2008, n = 6652 blodprov) och (2010, n = 6121 blodprov) från elva hälsocentraler i ett landsting. Slutligen, intervjuades 30 provtagande personal från 10 hälsocentraler efter att de deltagit i interventionsprogrammet. Intervjuerna var öppna och genererade korta berättelser och analyserades med innehållsanalys. Resultat: Venprovtagningsenkäten befanns vara valid och kan användas för att utvärdera personalens följsamhet till provtagningsanvisningar i venprovtagning och identifiera riskhändelser. Interventionsgruppen visade flera signifikanta förbättringar i självrapporterat utförande av venprovtagning såsom förbättrad informationssökning, vila inför provtagning, remissförfarande, kontroll av patientidentitet, användning av stas och etikettering av provrör. Kontrollgrupen visade inga signifikanta förbättringar. Blodprovskvaliteten visade små skillnader. Provtagande personals erfarenheter från intervjuerna sammanfattades i ett övergripande tema; utbildningsinsatsen öppnade upp möjligheter för reflektion om säkerhet.   Slutsats: Avhandlingen är så vitt vi vet den första att utvärdera effekten av ett storskaligt interventionsprogram med hjälp av självrapporterat utförande av venprovtagning och blodprovers kvalitet (låggradig hemolys). Med dessa metoder ökar andelen riskhändelser så att jämförelser kunde göras även på enhetsnivå och avdelningsnivå. Utbildningsprogrammet öppnade upp för reflektioner om säkerhet och förbättrade utförande av venprovtagning vid enheter med större brister. Utbildningsprogram som öppnar upp för reflektion och diskussion kan leda till ökad patientsäkerhet i hälso- och sjukvården. Trots utfallet av resultaten, är riktade utbildningsinsatser för sjukvårdsenheter som uppvisar specifika brister troligtvis mer effektiva än breda utbildningsinsatser. Klinisk betydelse: Interventionsprogram avseende preanalys och venös provtagning förbättrade personalens praktiska utförande. Monitorering av och åtgärder för att minska riskhändelser är väl fungerande preventiva åtgärder. Instrumenten (självrapporterande enkät och hemolys) bör också testas i andra kontexter inom hälso- och sjukvården. Ett externt nationellt program för att identifiera och förebygga riskhändelser bör utvecklas i hälso- och sjukvården. Interventioner i form av e-lärande kan då vara ett alternativ som är billigt och effektivt. Dessutom kan systematisk planering och genomförande med fokus på reflektion av specifika delar i en färdighet vara effektivt för att uppnå förbättringar. Våra studier har bidragit till en djupare och utökad kunskap om effekten av ett interventionsprogram på utförande av venprovtagning. Resultaten kan användas vid framtida planering av utbildningsinsatser. Modeller för praktiskt färdighetsutövande inom omvårdnad kan beskriva venprovtagning ur ett helhetsperspektiv och synliggöra venprovtagning som en viktig praktisk färdighet inom omvårdnad. / Preanalys
82

Statistische Auswertung der Bruchspannung einaxialer Zugversuche an Textilbeton - Vorschläge für Teilsicherheitsbeiwerte

Sickert, Jan-Uwe, Schwiteilo, Katrin, Jesse, Frank 02 December 2011 (has links) (PDF)
Im Rahmen umfangreicher experimenteller Untersuchungen wurden die Bruchspannungen für Textilbeton unter einaxialer, einsinniger Zugbelastung ermittelt. Im Ergebnis liegen variierende Daten vor, die auf eine nichtdeterministische (unscharfe) Bruchspannung hinweisen. Die Versuchsergebnisse stellen eine moderate Datenbasis für eine statistische Auswertung und Quantifikation der Unschärfe dar. Zur Berücksichtigung der unscharfen Bruchspannung bei der Bemessung mittels einfacher Handrechnungen muss ein deterministischer Sicherheitsabstand eingeführt werden. Der Sicherheitsabstand wird in den derzeit gültigen Normen mit Teilsicherheitsbeiwerten festgelegt, die ein ebenso normativ vorgegebenes Sicherheitsniveau gewährleisten sollten. In diesem Kontext werden im Beitrag auf der Basis von Zuverlässigkeitsbetrachtungen ermittelte Teilsicherheitsbeiwerte für Textilbeton mit AR-Glas- und Carbon-Bewehrung vorgeschlagen. / In the framework of a comprehensive experimental program the ultimate strength of textile reinforced concrete has been determined under consideration of uniaxial tensile load. In result varying data are available which indicate a non-deterministic (uncertain) strength. The experimental results provide a moderate basis for statistical evaluations and the quantification of uncertainty. Furthermore, manual calculation in structural design requires a certain safety distance. For this task, partial safety factors have been defined and incorporated in the design codes to ensure a predefined safety level. In this context, this paper gives suggestions for the definition of partial safety factors for textile reinforced concrete with AR glass and carbon reinforcement.
83

Postmortem toxicology : aspects on interpretation /

Holmgren, Per, January 2004 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 4 uppsatser.
84

Avaliação de integridade de dutos do aço API 5L X70 em meios etanólicos

Moraes, Pedro Martins January 2016 (has links)
Há atualmente um grande aumento na demanda por fontes de energia renováveis e de combustíveis que sejam menos poluentes, isto faz com que o etanol ganhe uma grande notoriedade como uma boa alternativa as fontes convencionais de energia. A tendência é de um grande aumento no consumo deste produto, para os próximos anos, o que vai exigir meios de transporte e estocagem seguros e eficientes, desde os produtores até os terminais de distribuição. Economicamente o melhor modo de transportar este produto é, sem nenhuma dúvida, através de dutos de aço, no entanto, existem estudos comprovando que alguns tipos de etanol são nocivos ao material empregado nos dutos. Dentre os modos de avaliar esta influência está a avaliação da tenacidade do material frente ao meio de interesse. Este trabalho tem por objetivo avaliar a tenacidade de um aço API 5L X70 quando exposto aos meios etanol de milho e etanol de cana, variando também o tempo de exposição do material no meio. Além disto, neste trabalho foram feitos diagramas FAD com os valores de tenacidade encontrados em escala reduzida para obter-se um indicativo da integridade estrutural do duto. Para tanto, foram preparados 10 corpos de prova do tipo C(T) entalhados e pré-trincados, respeitando a norma ASTM E647-08 e distribuídos da seguinte forma: 2 corpos de prova para ensaios ao ar, 4 corpos de prova para ensaios em meio etanol de cana e 4 corpos de prova para os ensaios em etanol de milho, além disto, foi utilizado o programa Vindio para a confecção dos diagramas FAD. Os resultados mostraram que os meios etanólicos de cana obtiveram resultados muito parecidos com os ensaiados ao ar, enquanto que no meio etanólico de milho fica evidenciada a fragilidade do material. Nas imagens fractográficas dos corpos de prova ensaiados foi confirmada a diferença na forma de fratura (frágil, no caso do etanol de milho e dúctil no etanol de cana e ao ar). / Nowadays, there is a large increase in the demand for renewable sources of energy and fuels more environment-friendly, this fact fortifies the ethanol’s image as a attractive alternative to conventional energy sources. The upward trend in the consumption of this product in the coming years will require safety and efficiently transportation and storage from producers to distribution terminals. Undoubtedly, the most economically way to transport this product is through pipelines, however, there are studies showing that some types of ethanol are damaging to the pipes material. One way to evaluate this harmful effect of ethanol is the toughness study of the material in the environment of interest. This study aims to assess the tenacity of the API 5L X70 steel when exposed to corn ethanol and sugarcane ethanol for different immersion times. Furthermore, to obtain an indication of the pipe’s structural integrity, FAD’s diagrams were plotted with toughness values determined in the small scale test. For this proposal, 10 C(T) specimens were notched and pre-cracked in accordance to the ASTM E647-08 and distributed as follows: 2 CPs for air test, 4 CPs for the sugarcane ethanol medium and 4 CPs for the corn ethanol. In addition, the Vindio software was used to make the FAD’s diagrams. The results showed that the tests realized in the air and in the sugarcane ethanol medium were very similar, while in the corn ethanol medium is evident the fragility of the material. The surface fracture confirmed the fragile behavior for specimen tested in the corn ethanol medium and ductile behavior for the sugarcane ethanol medium.
85

Análise teórico-experimental de um tabuleiro misto madeira-concreto composto por vigas circulares /

Alcântara Segundinho, Pedro Gutemberg de. January 2005 (has links)
Orientador: José Antônio Matthiesen / Banca: Renato Bertolino Junior / Banca: Antonio Alves Dias / Resumo: O estudo em estruturas mistas é dedicado ao emprego do material madeira-concreto em estruturas de pontes, mais precisamente no seu tabuleiro. No entanto, a aplicação desse material no Brasil não está regulamentada por normas que permitam ao engenheiro civil fazer sua aplicação nas estruturas correntes. Com a proposta de viabilizar o uso desse material madeira-concreto esse estudo vem contribuir com um melhor entendimento do comportamento físico da ligação entre os materiais madeira e concreto. O estudo dessa ligação foi realizado quantificando o módulo de deslizamento em corpos-de-prova do tipo "push-out", vigas T e tabuleiro de madeira-concreto. Os resultados experimentais do módulo de deslizamento obtidos por esses três tipos de ensaios foram comparados com os resultados obtidos teoricamente pelo Eurocode 5 (1993). Também, no seguinte estudo foi feito uma simulação numérica do tabuleiro de madeira-concreto usando um programa para análise estrutural baseado no Método dos Elementos Finitos (MEF). Na conclusão dessa pesquisa verificou-se que o comportamento estrutural desse material misto pode-ser calculado usando o Eurocode 5 (1993) e o Método dos Elementos Finitos (MEF). / Abstract: The study of mixed structures is dedicated to the use of timber-concrete material in bridges' structures, more precisely in its tray. However, the application of this material in Brazil is not regulated by standards that allow the civil engineer to make its application in the current structures. With the proposal to make possible the use of this timber-concrete material this study contributes to understand better the physical behavior of the linking between wood and concrete. The study of this connection was carried through quantifying the slip's module in specimens of "push-out" type, T beams and timber-concrete's tray. The experimental results of the slip's module from these three kinds of tests had been compared with the results obtained theoretically for Eurocode 5 (1993). Also, in the following study it was made a mathematical simulation of the wood-concrete's tray using a numerical analysis' program based on the Finite Elements' Method (MEF). In the conclusion of this research it was verified that the structural behavior of this mixed material can to be calculated using Eurocode 5 (1993) and the Method of the Finite Elements (MEF). / Mestre
86

Avaliação de integridade de dutos do aço API 5L X70 em meios etanólicos

Moraes, Pedro Martins January 2016 (has links)
Há atualmente um grande aumento na demanda por fontes de energia renováveis e de combustíveis que sejam menos poluentes, isto faz com que o etanol ganhe uma grande notoriedade como uma boa alternativa as fontes convencionais de energia. A tendência é de um grande aumento no consumo deste produto, para os próximos anos, o que vai exigir meios de transporte e estocagem seguros e eficientes, desde os produtores até os terminais de distribuição. Economicamente o melhor modo de transportar este produto é, sem nenhuma dúvida, através de dutos de aço, no entanto, existem estudos comprovando que alguns tipos de etanol são nocivos ao material empregado nos dutos. Dentre os modos de avaliar esta influência está a avaliação da tenacidade do material frente ao meio de interesse. Este trabalho tem por objetivo avaliar a tenacidade de um aço API 5L X70 quando exposto aos meios etanol de milho e etanol de cana, variando também o tempo de exposição do material no meio. Além disto, neste trabalho foram feitos diagramas FAD com os valores de tenacidade encontrados em escala reduzida para obter-se um indicativo da integridade estrutural do duto. Para tanto, foram preparados 10 corpos de prova do tipo C(T) entalhados e pré-trincados, respeitando a norma ASTM E647-08 e distribuídos da seguinte forma: 2 corpos de prova para ensaios ao ar, 4 corpos de prova para ensaios em meio etanol de cana e 4 corpos de prova para os ensaios em etanol de milho, além disto, foi utilizado o programa Vindio para a confecção dos diagramas FAD. Os resultados mostraram que os meios etanólicos de cana obtiveram resultados muito parecidos com os ensaiados ao ar, enquanto que no meio etanólico de milho fica evidenciada a fragilidade do material. Nas imagens fractográficas dos corpos de prova ensaiados foi confirmada a diferença na forma de fratura (frágil, no caso do etanol de milho e dúctil no etanol de cana e ao ar). / Nowadays, there is a large increase in the demand for renewable sources of energy and fuels more environment-friendly, this fact fortifies the ethanol’s image as a attractive alternative to conventional energy sources. The upward trend in the consumption of this product in the coming years will require safety and efficiently transportation and storage from producers to distribution terminals. Undoubtedly, the most economically way to transport this product is through pipelines, however, there are studies showing that some types of ethanol are damaging to the pipes material. One way to evaluate this harmful effect of ethanol is the toughness study of the material in the environment of interest. This study aims to assess the tenacity of the API 5L X70 steel when exposed to corn ethanol and sugarcane ethanol for different immersion times. Furthermore, to obtain an indication of the pipe’s structural integrity, FAD’s diagrams were plotted with toughness values determined in the small scale test. For this proposal, 10 C(T) specimens were notched and pre-cracked in accordance to the ASTM E647-08 and distributed as follows: 2 CPs for air test, 4 CPs for the sugarcane ethanol medium and 4 CPs for the corn ethanol. In addition, the Vindio software was used to make the FAD’s diagrams. The results showed that the tests realized in the air and in the sugarcane ethanol medium were very similar, while in the corn ethanol medium is evident the fragility of the material. The surface fracture confirmed the fragile behavior for specimen tested in the corn ethanol medium and ductile behavior for the sugarcane ethanol medium.
87

Avaliação da coleta de sangue em papel de filtro para diagnóstico molecular da dengue / Evaluation of blood collected in fta cards for the detection of dengue virus RNA

Célia Luiza de Lima Rodrigues 21 October 2010 (has links)
O diagnóstico rotineiro da dengue é realizado com amostra de sangue dos casos suspeitos. A coleta tradicional de sangue (por punção venosa) é um procedimento que dificulta a realização de exames e pesquisas por ser um procedimento invasivo que nem sempre é prático para crianças e bebês, requer pessoal especializado e necessita de um local para armazenamento da amostra sob refrigeração ou congelamento. O propósito deste estudo foi coletar amostras por punção digital com uma nova tecnologia (FTA Card) e compará-la com amostras coletadas por punção venosa, avaliando-as através de uma técnica molecular de PCR em tempo real. Sendo o PCR em Tempo Real a técnica molecular atualmente disponível de maior rapidez, sensibilidade e especificidade, padronizamos uma metodologia de passo único de PCR em Tempo Real com SYBR green baseando-se na região 3 não codificante do vírus e utilizando primers degenerados, capazes de detectar os quatro sorotipos de uma só vez. A avaliação das técnicas de coleta e amplificação foram feitas com amostras suspeitas de dengue, obtidas em Goiânia durante surto ocorrido no ano de 2008. O limite de detecção da reação padronizada no presente estudo foi de aproximadamente 100 cópias/ml e uma especificidade de 100%. Para tipagem das amostras positivas a técnica empregada foi o PCR multipex. Dentre as 89 amostras coletadas 60 (67%) foram positivas para àquelas coletadas por punção venosa e 14 (16%) para àquelas coletadas por punção digital. Dentre as 89 amostras para o PCR em Tempo Real, apenas 29 (32%), foram tipadas pelo método de PCR multiplex, sendo 3 casos do vírus da dengue 1 (10%), 16 casos do vírus da dengue 2 (55%), e 10 casos do vírus da dengue 3 (35%). Descritores: Dengue/diagnóstico, coleta de amostras sanguíneas, reação em cadeia da polimerase, corantes fluorescentes / The collection by venipuncture is a procedure that is difficult to carry out in diagnosis and research because it is an invasive procedure that is not always practical for children and babies , requires specialized staff, needs a place to store the sample under refrigeration or forzen, This study aimed to collect samples by fingerstick puncture with a new technology named FTA card and compare it with samples collected by venipuncture, using a realtime PCR to evaluate if FTA card collection would have a similar performance to standard blood sampling. Towards that, we obtained viral load values in order to estimate the differences not only qualitatively (e.g. pos or neg) but also in numbers.. We used an one-step SYBR Green I Real-Time PCR based on the region 3 \'noncoding virus using degenerate primers which was able to detected all four serotypes of dengue virus. Among the 89 samples collected 60 (67%) were positive for those collected by venipuncture and 14 (16%) to those collected by fingerstick, Only 29 (32%) were possible to be typed by PCR multiplex. Three cases were dengue virus 1 (10%), 16 cases were dengue virus 2 (55%) and 10 cases were dengue virus 3 (35%). The limit of detection obtained was approximately 100 copies / ml and aspecificity of 100% was observed. Keywords: Dengue / diagnosis, collection of blood samples, polymerase chain reaction, fluorescent dyes
88

Utvärdering av Copan EswabTM för viabilitet av bakterier / Evaluation of Copan Eswab™ for viability of bacteria

Hannu, Olof, Hagman, Leonardo January 2017 (has links)
Bakterier har alltid haft en stor inverkan på mänskligheten. För att diagnostisera bakteriella sjukdomar och behandla dem krävs identifiering av bakterien eller bakteriens relevanta egenskaper. Transportmedium har utvecklats för att hålla bakterierna vid liv från provtagning till analys. Syftet med studien var att utvärdera bakteriers viabilitet i det vätskebaserade mediet Copan Eswab jämfört med kolmedium (Copan swab). Bakterierna som ingick i studien var Campylobacter jejuni, Streptococcus pneumoniae, Haemophilus influenzae, Niesseria gonorrhoeae och Fusobacterium nucleatum. Förutom jämförande mellan medierna genomfördes en jämförelse mellan Eswab i kyl och i rumstemperatur. Resultaten för H. influenzae (n=9) och N. gonorrhoeae (n=9) visade att Eswab gav lika många eller fler överlevande bakterier. Gällande F. nucleatum (n=9) visade resultaten att fler överlevde i Copan swab (Copanpinnar) de första 28 timmarna, men även att bakterien inte klarar mer än 28 timmar i rumstemperatur. Gällande S. pneumoniae (n=9) och C. jejuni (n=9) gav båda opålitliga svar. Ytterligare mätpunkter och studier krävs för att erhålla mer pålitliga resultat gällande hur länge bakterierna överlever i Eswab. / Bacteria have always had a great influence on mankind. To diagnose any bacterial disease and treat it it’s necessary to identify the bacteria or any relevant attributes. Different types of specimen transport have been developed to keep the bacteria alive from sampling until the analysis is performed. The purpose of the study was to evaluate the viability of bacteria in the fluid-based media Copan EswabTM compared with charcoal medium (Copan swab). Bacteria included in the study were: Campylobacter jejuni, Streptococcus pneumoniae, Haemophilus influenzae, Niesseria gonorrhoeae and Fusobacterium nucleatum. The study also tried to compare how bacteria survived in Eswab which was refrigerated and in Eswab room temperature. Results for H. influenzae (n=9) and N. gonorrhoeae (n=9) showed that an equal amount or more of the bacteria survived in Eswab. More of F. nucleatum (n=9) survived in Copan swab (Copan swab sticks) for the first 28 hours, additionally they showed that the bacteria won’t survive more than 28 hours in room temperature. Regarding S. pneumoniae (n=9) and C. jejuni (n=9) both displayed unreliable results. Overall more measurements and additional studies are needed for more reliable results.
89

The responses of ectohydric and endohydric mosses under ambient and enhanced ultraviolet radiation

Lappalainen, N. (Niina) 08 June 2010 (has links)
Abstract Previous reports on the effects of enhanced UV-B radiation on bryophytes have been equivocal. This study shows that mosses not only respond to enhanced UV-B, but they are affected by changes in ambient radiation. The studies were conducted with two model species common in northern environments; red-stemmed feather moss (Pleurozium schreberi) and juniper haircap moss (Polytrichum juniperinum). Both species showed high concentrations of methanol-extractable UV-absorbing compounds (UACs) with high spring-time and early-summer UV, whereas in P. juniperinum, the concentration was affected by early-summer drought. The UACs of P. juniperinum increased again towards autumn suggesting a role in winter hardening. The (spring-time) cell wall-bound UV screen was important to both species. The fundamental adaptation of P. juniperinum to open and exposed environments was reflected in relatively higher concentrations of total UACs compared to P. schreberi. The enhanced UV-B experiments in situ were conducted over two years in Oulu and six years at the FUVIRC site in Sodankylä. Some of the effects of UV-B were seen within the first years of the experiments, or even within hours, while others were observed after several years. Five or six years of enhanced UV-B treatment increased the methanol-extractable UACs of P. schreberi and decreased the green shoot growth of P. juniperinum. The immediate light environment was proposed to have an impact on the varying UAC concentrations. Some mitigating effects of UV-A were observed as well. Off-site measured, reconstructed and modelled UV radiation data was used for comparisons of light environment in situ, or when performing a reconstructive research with historical samples. The environmental sample banks can provide a useful tool to study past environmental conditions, and even reconstruct past radiation levels. It was shown in this study that UACs in P. schreberi and P. juniperinum have fundamental roles as UV-B screens in the cell walls, but there is also a variable response with the soluble fraction that reacts and adapts to the changes in UV radiation. The responses to increasing UV-B radiation vary in magnitude and in time. As P. schreberi and P. juniperinum possess circumboreal and cosmopolitan distributions, the effects of UV-B on these species and consequently on ecosystems has a broad application.
90

Shear Fracture and Delamination in Packaging Materials : A study of Experimental Methods and Simulation Techniques

Islam, Md. Shafiqul January 2016 (has links)
Packages are the means of preservation, distribution and convenience of use for food, medicine and other consumer products. Package opening is becoming complicated in many cases because of cutting cost in design and production of opening techniques. Introduction of new package opening technique, material or geometry for better opening experience, forces new design measurements which require a large number of prototype developments and physical testing. In order to achieve more rapid and accurate design, Finite Element Method (FEM) Simulations are widely used in packaging industries to compliment and reduce the number of physical testing. The goal of this work is to develop the building blocks towards complete package opening simulation. The study focuses on testing and simulation of shear fracture and shear delamination of packaging materials. A modified shear test specimen was developed and optimized by finite element simulation. Test method was validated for High-density polyethylene (HDPE) and Polypropylene (PP). The developed method has been accepted by international standards organization ASTM. Based on linear elastic fracture mechanics, a geometry correction factor of shear fracture toughness for the proposed specimen was derived. The study concluded that, for ease of opening, HDPE is a more favorable material for screw caps than PP. When performing the experiment with the shear specimen to find essential work of fracture, the ligament length should be varied between twice of the thickness and half of the width of the specimen ligament. Multi-layered thin laminate of Low-density polyethylene (LDPE) and aluminum (Al), also known as Al/LDPE laminate, is another key object addressed in this study. Continuum and fracture testing of individual layers provided the base information and input for numerical modeling. The propagation of an interfacial pre-crack in lamination in Al-LDPE laminate was simulated using several numerical techniques available in the commercial FEM solver ABAQUS, and it was concluded that using the combination of VCCT technique to model the interfacial delamination and coupled elasto-plastic damage constitutive for Al and LDPE substrates can describe interfacial delamination and failure due to necking. It was also concluded that the delamination mode in a pre-crack tip is influenced by the ratio of fracture energy release rate of mode I and II. To address the challenge in quantifying shear energy release rate of laminate with very thin substrate, a convenient test technique is proposed. Additionally, scanning electron microscopic study provided useful information on fractured and delaminated surfaces and provided evidence that strengthened the conclusions of this work. The proposed test methods in this work will be crucial to measure the shear mechanical properties in bulk material and thin substrates. Laminates of Al and LDPE or similar material can be studied using the developed simulation technique which can be effectively used for decision support in early package development.

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