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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.
331

Preanalytisk inverkan av provtagningsrör vid zinkanalys i plasma / Preanalytic Effect of Sampling Tubes in Zinc Analysis in Plasma

Abezie, Henock January 2020 (has links)
No description available.
332

A Consensus Curriculum for Laboratory Management Training for Pathology Residents

Weiss, Ronald L., McKenna, Barbara J., Lord-Toof, Melissa, Thompson, Nancie Noie, Datnow, Brian, Dysert, Peter A., Inamdar, Kedar V., Kaul, Karen L., Kirkley, Scott A., Mullersman, Jerald E., Roseff, Susan D., Stanton, Constance A., Stowell, Christopher P., Terrazas, Enrique, Zander, Dani S. 01 November 2011 (has links)
Through the combined efforts of the American Pathology Foundation (APF), the American Society for Clinical Pathology (ASCP), and the Program Directors Section (PRODS) of the Association of Pathology Chairs (APC), a needs assessment was performed via a survey on the PRODS listserv, workshops at the APC/PRODS annual meetings in 2009 and 2010, and a Work Group of representatives of APF, ASCP, and PRODS. Residency program needs and resource constraints common to training pathology residents in practice and laboratory management were identified. In addition, a consensus curriculum for management training was created to serve as a resource for residency training program directors and others. The curriculum was converted into a "wiki" design tool for use by program directors, residents, and faculty.
333

Automating Laboratory Operations by Intergrating Laboratory Information Management Systems (LIMS) with Analytical Instruments and Scientific Data Management System (SDMS)

Zhu, Jianyong 06 1900 (has links)
Submitted to the faculty of the University Graduate School in partial fulfillment of the requirements for the degree Master of Science in the School of Informatics, Indiana University June 2005 / The large volume of data generated by commercial and research laboratories, along with requirements mandated by regulatory agencies, have forced companies to use laboratory information management systems (LIMS) to improve efficiencies in tracking, managing samples, and precisely reporting test results. However, most general purpose LIMS do not provide an interface to automatically collect data from analytical instruments to store in a database. A scientific data management system (SDMS) provides a “Print-to-Database” technology, which facilitates the entry of reports generated by instruments directly into the SDMS database as Windows enhanced metafiles thus to minimize data entry errors. Unfortunately, SDMS does not allow performing further analysis. Many LIMS vendors provide plug-ins for single instrument but none of them provides a general purpose interface to extract the data from SDMS and store in LIMS. In this project, a general purpose middle layer named LabTechie is designed, built and tested for seamless integration between instruments, SDMS and LIMS. This project was conducted at American Institute of Technology (AIT) Laboratories, an analytical laboratory that specializes in trace chemical measurement of biological fluids. Data is generated from 20 analytical instruments, including gas chromatography/mass spectrometer (GC/MS), high performance liquid chromatography (HPLC), and liquid chromatography/mass spectrometer (LC/MS), and currently stored in NuGenesis SDMS iv (Waters, Milford, MA). This approach can be easily expanded to include additional instruments.
334

Effect of FGF21 on short-term white adipocyte adiponectin secretion

Kristofersdottir, Isidora Anna January 2020 (has links)
Reduced levels of white adipocyte hormone adiponectin have been observed in obese individuals with type 2 diabetes (T2D). Higher adiponectin levels are monotonically associated with a lower risk of T2D and hence increasing circulating adiponectin levels is of great interest in diabetic research. A novel compound, called fibroblast growth factor 21 (FGF21), is showing great potential in treatment of obesity and T2D. In animal models with obesity and T2D FGF21 increases glucose uptake, improves lipid homeostasis, decreases fat mass and increases circulating adiponectin levels. In this study, theaim is to explore the acute effect of FGF21 on white adipocyte adiponectin secretion. Adiponectinsecretion experiments were performed on primary murine adipocytes incubated with FGF21 for 30minutes and adiponectin levels were measured with ELISA and normalised to total protein content.To study the signalling pathway of FGF21, a separate batch of murine adipocytes were pretreated with an Epac and PI3K inhibitor prior to addition of FGF21. Results from this thesis show that FGF21potently stimulates short-term adiponectin release via PI3K-dependent pathways with no effect on adiponectin synthesis.
335

Gene expression of MYPT1 and ROCK1 in endometrial cancer

Ziou, Arisa January 2015 (has links)
Endometrial adenocarcinoma is a cancer that develops from the endometrium, from cells thatform the glands in the endometrium. Animal models such as the BDII rat have thecharacteristic property that they are prone to cancers, characterized by rapid tumor growth,that resemble human cancers. Such rat models are therefore used to study gene expression andsignal pathways in cancer. Cancer cells have the ability to invade surrounding tissues throughlymphatic and/or vascular circulation to produce secondary tumors at new sites. TheRho/ROCK pathway orchestrates cell motility thereby contributing in significantly tometastasis. ROCK, through phosphorylation of myosin phosphatase target subunit 1(MYPT1), inhibits MYPT1 and induces actomyosin contraction which contributes to manycellular processes. In this study, we were interested in investigating the expression of MYPT1and ROCK1 genes in malignant and non-malignant endometrial cell lines in BDII rat model,in human endometrial cancer cells represented by the Ishikawa cells line, and in humanembryonic kidney 293 (HEK293) human non-malignant control cells. Although statisticalsignificance was not reached due to the small sample size, a difference in the gene expressionlevels in malignant and non-malignant cells was observed. The results from the present studyshowed a higher expression of MYPT1 and ROCK1 genes in cancer cells (rat and human)compared to non-cancer cells, and we can conclude that this implicates the significance of theMYPT1/ROCK pathway in endometrial cancer and its deregulation.
336

Emotional Intelligence in Medical Laboratory Science

Price, Travis Miles 01 May 2013 (has links)
The purpose of this study was to explore the role of emotional intelligence (EI) in medical laboratory science, as perceived by laboratory administrators. To collect and evaluate these perceptions, a survey was developed and distributed to over 1,400 medical laboratory administrators throughout the U.S. during January and February of 2013. In addition to demographic-based questions, the survey contained a list of 16 items, three skills traditionally considered important for successful work in the medical laboratory as well as 13 EI-related items. Laboratory administrators were asked to rate each item for its importance for job performance, their satisfaction with the item's demonstration among currently working medical laboratory scientists (MLS) and the amount of responsibility college-based medical laboratory science programs should assume for the development of each skill or attribute. Participants were also asked about EI training in their laboratories and were given the opportunity to express any thoughts or opinions about EI as it related to medical laboratory science. This study revealed that each EI item, as well as each of the three other items, was considered to be very or extremely important for successful job performance. Administrators conveyed that they were satisfied overall, but indicated room for improvement in all areas, especially those related to EI. Those surveyed emphasized that medical laboratory science programs should continue to carry the bulk of the responsibility for the development of technical skills and theoretical knowledge and expressed support for increased attention to EI concepts at the individual, laboratory, and program levels.
337

The Effect of Modeling on Cooperation in the Laboratory and in the Natural Environment

Siegel, Janice V. 01 May 1980 (has links)
In this study a multiple-baseline design was used to determine the effectiveness of three different modeling sequences in increasing cooperative behavior in children in a laboratory situation. The research also assessed the short- and long-term effects of the laboratory procedures on children's behavior in a free-play setting. Subjects were 9 pairs of preschool-aged children. In the laboratory situation pairs of subjects performed a block-stacking task which allowed them to respond either cooperatively or independently. Following baseline periods of varying lengths, the pairs of children were exposed to one of three videotapes of cooperative models. In Tape 1 adult models demonstrated cooperative behavior, but exhibited no verbal behavior. In Tape 2 the models made positive statements about cooperation contiguous with the demonstration of cooperative behavior. In Tape 3 the models demonstrated cooperation, made contiguous positive statements about cooperation, and in addition, they received differential positive reinforcement for cooperation. Although three of nine teams showed a significant increase in mutually cooperative responding, consistent multiple baseline control was not demonstrated. Therefore, it could not be conclusively stated that the videotaped cooperative models were effective in increasing children 1 s mutually cooperative responding in the laboratory. A significant increase in parallel play was noted between laboratory partners in free-play periods immediately following the laboratory sessions; however, this increased interaction was not obvious when 5-day and 6-week follow-up observations were made.
338

The Effect of Modeling on Cooperation in the Laboratory and in the Natural Environment

Siegel, Janice V. 01 May 1980 (has links)
In this study a multiple-baseline design was used to determine the effectiveness of three different modeling sequences in increasing cooperative behavior in children in a laboratory situation. The research also assessed the short- and long-term effects of the laboratory procedures on children's behavior in a free-play setting. Subjects were 9 pairs of preschool-aged children. In the laboratory situation pairs of subjects performed a block-stacking task which allowed them to respond either cooperatively or independently. Following baseline periods of varying lengths , the pairs of children were exposed to one of three videotapes of cooperative models . In Tape l adult models demonstrated cooperative behavior, but exhibited no verbal behavior. In Tape 2 the models made positive statements about cooperation contiguous with the demonstration of cooperative behavior. In Tape 3 the models demonstrated cooperation, made contiguous positive statements about cooperation, and in addition, they received differential positive reinforcement for cooperation. Although three of nine teams showed a significant increase in mutually cooperative responding, consistent multiple baseline control was not demonstrated . Therefore, it could not be conclusively stated that the videotaped cooperative models were effective in increasing children's mutually cooperative responding in the laboratory. A significant increase in parallel play was noted between laboratory partners in free-play periods immediately following the laboratory sessions; however, this increased interaction was not obvious when 5-day and 6-week follow-up observations were made.
339

Etude expérimentale de la désorption et de la réactivité des espèces azotées sur les grains de poussière interstellaire / Experimental study of desorption and reactivity of nitrogen bearing species on interstellar dust grains

Nguyen Thanh, Hoang Phuong 15 October 2018 (has links)
Le milieu interstellaire est un élément essentiel des galaxies. Il est en effet la matrice de la formation des étoiles et des planètes. Il est composé de gaz et de poussières interstellaires. Il est généralement admis que la présence de molécules organiques complexes (COM) est due aux réactions en phase gazeuse. Toutefois, la synthèse de certaines espèces clés (i.e. H2,H2O, CO2, etc.) nécessite l'intervention des réactions en phase solide c'est à dire sur les grains de poussière. Plus de 200 molécules, dont des COM, ont été détectées dans l'ISM. et les enveloppes circumstellaires. Certaines de ces COM contiennent déjà du carbone, de l'oxygène, et de l'azote, qui sont les principaux éléments chimiques de la composition des molécules à partir desquelles la vie terrestre s'est construite. L'objectif de cette thèse est de comprendre les processus physiques et chimiques (diffusion, désorption et réactivité) qui se produisent sur les grains de poussière interstellaire. Plus spécifiquement, ma thèse se concentre sur l’étude de la désorption et de la réactivité des espèces azotées qui peuvent mener à des COM par des processus liés à l'hydrogénation. Toutes les expériences ont été réalisées avec l'expérience VENUS située au laboratoire LERMA à l'université de Cergy Pontoise, France. VENUS est composée d'une chambre à ultra-vide (UHV), appelée chambre principale, dotée d'une pression de base d'environ 10-10 mbar. Des atomes/molécules sont dirigées vers un porte-échantillon dans la chambre UHV au moyen d'un système à quatre faisceaux séparés. La température du porteéchantillon peut être contrôlée entre 7 K à 400 K. Les produits sont sondés par spectrométrie de masse et spectroscopie infrarouge par réflexion en adsorption. Différents environnements ont été utilisés : surface d'or ou substrats de glace d'eau (glace amorphe compacte ou poreuse et glace cristalline) pour imiter les différents environnements astrophysiques. Nous avons procédé à des expériences impliquant certains atomes et molécules comme l'hydrogène, le deutérium, l'oxygène, le CO, N2, NO, H2O, H2O, H2CO, CH3CN et CH3NC. Ces espèces ont été déposées sur une surface froide maintenue à 10 K (et jusqu'à 40 K). CO et N2 ont été déposés sur des substrats de glace d'eau pour étudier les différents comportements des adsorbats ainsi que la distribution des énergies de désorption et le mécanisme de ségrégation. Nous avons étudié l'efficacité de la pénétration des atomes (oxygène et hydrogène) dans la glace d'eau poreuse. Nous avons utilisé le NO comme traceur chimique. A partir de l'analyse de la consommation de NO, nous avons estimé la pénétration des atomes O ou D à travers la glace d'eau poreuse. Nous avons procédé à de nouvelles expériences sur l'hydrogénation du NO et nous avons constaté qu'il existe une barrière d'activation à l'étape HNO + H. Cependant, les atomes H peuvent traverser cette barrière d'activation par effet tunnel sur une surface maintenue à 8 K. Nous avons montré que l'hydroxylamine (NH2OH) est le principal produit de l'hydrogénation du NO à basse température, mais que le N2O est le principal produit à haute température. Nous présentons également les voies chimiques possibles de formation du formamide (NH2CHO) , molécule clé de la chimie pré-biotique, par co-hydrogénation de NO et de H2CO sur une surface froide (typiquement à 10 K). Nous avons analysé et montré l'efficacité de cette voie de formation du formamide sur les grains interstellaires. Nous avons montré que le réseau chimique de l'hydrogénation du CH3CN et du CH3NC est complexe et se fait par différents mécanismes qui sont en compétition. Nous avons mesuré et montré que l'hydrogénation est le mécanisme dominant. De plus, la présence de H2O augmente l'efficacité réactive. De nombreux processus chimiques en phase solide ont été simulés dans le contexte astrophysique de la formation de COM. / The interstellar medium is a key component of galaxies which is the matrixof the formation of stars and planets. It is composed of interstellar gas and dust grains. The presence of complex organic molecules (COMs) can be understoodvia reactions in the gas phase. However, the synthesis of some key species (i.e H2, H2O, CO2, etc) needs the intervention of the solid-state reactions on dust grains surface. More than 200 molecules including COMs have been detected in ISMand circumstellar shells. Some of these COMs already contain carbon, oxygen,and nitrogen, which are the main chemical elements in the composition of themolecules on which terrestrial life is built. The aim of this thesis is to understand physical and chemical processes (i.e diffusion, desorption, and reactivity) occurring on interstellar dust grains. More specifically, my thesis focuses on the investigation of desorption and reactivity of nitrogen bearing species that lead to COMs by hydrogenation related processes.All experiments were performed with the VENUS set-up located at the LERMACergy laboratory in the university of Cergy Pontoise, France. VENUS is composedof an Ultra High Vacuum (UHV) chamber, so called the main chamber, with abasis pressure around of 10 −10 mbar. Atoms/molecules were injected onto a sample holder in the UHV chamber through a separated four beamline system. The sample holder is controlled in temperature from 7 K to 400 K. Products are probed by using mass spectrometer and reflection adsorption infrared spectroscopy. Different solid states environments have been used: gold surface or water ice substrates (compact amorphous solid water, porous amorphous solid water, and crystalline ice) to mimic different the astrophysical environments.We proceeded experiments involving some atoms and molecules such as hydrogen,deuterium, oxygen, CO, N2, NO, H2O, H2CO, CH3CN, and CH3NC. These specieswere deposited on the cold surface held at 10 K (up to 40 K). CO and N2 weredeposited on water ice substrates to study different adsorbed behaviours as well as the distribution binding energy and the segregation mechanism. We studied theefficiency of atoms (i.e oxygen and hydrogen) penetration into porous water ice.We used NO as a chemical tracer for the penetration of O and H atoms throughwater ice. From the analysis of the consumption of NO, we estimated the penetra-tion of O or D atoms through porous water ice. We proceed new experiments onthe hydrogenation of NO and found that there is an activation barrier at HNO H step. However, H atoms can cross the activation barrier via quantum tunnelingon the cold surface maintained at 8 K. We indicated that hydroxylamine (NH2OH)is the major product of the hydrogenation of NO at low temperatures, but N2O isthe major product at high temperatures. We also present possible chemical path-ways of the pre-biotic formamide (NH2CHO) through the co-hydrogenation of NOand H2CO on the cold surface (typically at 10 K). Simultaneously, we analysedand discussed the efficient formation route of formamide on interstellar grains. We showed that the chemical network of the hydrogenation of CH3CN and CH3NC iscomplex and takes place via different mechanisms which tend to be competitive.We measured and indicated that the hydrogenation is the dominant mechanism.Furthermore, H2O is always raising the reactive efficiency.
340

Inflammatory Cell Infiltration and Expression of AT1 and AT2 Receptors in Angiotensin II and High-Salt Diet-Induced Balb/CJ Mice

Herat, Avishka January 2023 (has links)
Pulmonary oedema and pulmonary hypertension are often associated with heart failure. The Balb/CJ and C57BL/6J mouse strains have been shown to exhibit distinct genetic susceptibilities to heart failure. Balb/CJ develops reduced heart function associated with pulmonary edema and pulmonary hypertension when treated with angiotensin II and a high-salt diet (ANG II + Salt) while C57BL/6J does not. The aim of this study was to investigate the effects of ANG II + Salt on lung damage by studying the potential immune cell infiltration in Balb/CJ mice and to determine whether differences in expression levels of angiotensin II type 1 and 2 (AT1 and AT2) receptors contribute to these effects. Protein expression of macrophages, neutrophils, AT1 receptors, and AT2 receptors in lung samples from six Balb/CJ mice and seven C57BL/6J mice treated with ANG II + Salt were analysed using Western blot. Five untreated mice from each strain were used as controls. The results indicated a significant difference (p=0.009) in the expression of macrophages between Balb/CJ mice treated with ANG II + Salt with a mean value of 17.30 and C57BL/6J mice treated with ANG II + Salt with a mean value of 9.34. No significant differences were observed in the expression of neutrophils, AT1 receptors, or AT2 receptors between the groups. Contrary to our expectations, the results did not support immune cell infiltration in Balb/CJ mice lungs or show higher AT1 receptor levels in Balb/CJ mice compared to C57BL/6J mice. Further research is required to understand the underlying mechanisms involved.

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