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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.
521

Bättre ut : En kvalitativ studie ur klientperspektiv om frigivning.

Welander, Ann-Sofie January 2006 (has links)
<p>The purpose of this study is to from a client point of view study the release process. The first issue is which positive and negative aspects on the release situations that are revealed trough the interviews. The second issue is which changes that are needed to improve the conditions for the release work to be crime preventive. The study has been performed by means of qualitative interviews with clients, and one person with a long professional experience of treatment of offenders. The results show that the release work has generally not been successful. This is, according to the clients, due to a lack of cooperation between the client and the authorities. The clients also mean that their own motivation is the base for change, but that they may need help to mobilize the motivation. The next step is to se to that the soberness and the motivation obtained during the time in prison is not destroyed shortly after release. This is a significant risk that has been described both in previous research and by the interviewees. It is a paradox to from one day as institutionalised to the next day as released be expected to take responsibility for all aspects of life. The release process is not finished when the prisoner leaves the prison. The subsequent release work needs to be improved. A possibility that came up during the interviews is to set up a post-release system in the form of apartments owned by the local authorities. Crime is a symptom of both social system problems and personal problems. However, both the previous research and the result of this study show a tendency that the client’s will to change often meets hinders caused by the social systems. It is on the social system level that improvements in the first place are needed.</p> / <p>Syftet med studien är att ur klientperspektiv studera frigivningssituationen. Första frågeställningen är vilka positiva och/eller negativa omständigheter som kommer fram om frigivningsarbetet. Den andra frågeställningen är vad som behöver förändras för att skapa bättre förutsättningar för att frigivningsarbetet ska förebygga återfall i brott. Studien har genomförts med hjälp av kvalitativa intervjuer med klienter samt en person med lång yrkeserfarenhet inom kriminalvården. Resultatet visar att frigivningsarbetet inte fungerat tillfredsställande. Detta har enligt klienterna sin grund i bristande samverkan mellan klient, Kriminalvård och övriga samhällsaktörer. Klienterna menar även att deras egen vilja är grunden för förändring men att det kan behövas hjälp att väcka den. Nästa steg är att se till att den nykterhet och vilja som uppnåtts under anstaltstiden inte raseras direkt efter frigivningen. Detta är en reell risk som har beskrivits både i intervjusvaren och i tidigare forskning. Det innebär en paradox att ena dagen vara institutionaliserad intagen till att som frigiven förväntas ta ansvar för sitt liv på alla plan. Frigivningsprocessen är inte avslutad i och med att klienten lämnar anstalten. Det frigivningsarbete som kvarstår behöver förbättras. Ett förslag som presenteras i intervjusvaren är inrättandet av ett mellansystem i form av kommunalägt boende. Kriminalitet är ett symtom på samhällsproblem likväl som det har individuella orsaker. I den tidigare forskningen och i intervjusvaren framtonar dock en bild av hur klientens vilja till förändring hindras av den ram samhällssystemet skapar. Det är i första hand på samhällsnivån som förbättringar behövs.</p>
522

Morgontidningar, kvällstidningar eller nättidningar? : – en kvalitativ studie av de unga vuxnas förhållningssätt till de olika tidningsformerna

Marino, Antonella January 2010 (has links)
<p>Title: Morning papers, evening papers or webb magazines? - a qualitative study about young adults attitudes about the different magazine types.Number of pages: 45Author: Antonella MarinoTutor: Göran SvenssonCourse: Media and communication studiesPeriod: Autumn term 2009University: Division of Media and communication, Department of Information Science, Uppsala University.Purpose/aim: The aim of this essay is to find out how young adults of the age of 20-30 discusses about the different types of news papers: morning papers, evening papers and Webb magazines. I have chosen four needs for my essay which are surveillance, emotional release/ entertainment, personal identity and interactivity. The purpose is to find out the differences between morning papers, evening papers and webb magazines. Which magazine type satisfies my four chosen needs in a best way? Which other conditions influence the young adults choices of magazine type? I will also try to find out if the new idea interactivity can be equivalent to the other three needs.Material/Method: I have used three groups for discussion for my essay. The three groups contained 4-5 people. Everyone was in the age of 20-30. I brought some friends of mine to the groups, who instead brought there friends. So everyone in the group knew someone, but not everybody.Main results: There were bigger differences between the attitudes towards morning- and evening papers than between them and the webb magazines. The young adults had positive attitudes towards morning papers, but very negative attitudes towards evening papers. The webb magazines depended on which type of magazine it was. If it was a morning paper in a webb version the attitudes were positive. So the morning papers and their versions in the webb satisfied the needs of the young adults in a best way. But of course the results were different, some of the young adults preferred the evening papers for entertainment and webb maqazines for surveillance and interactivity. The other conditions that influence the choices of the young adults for reading different types of papers were for example their personal attributes, their social situation but even occasions. I found interactivity equivalent to the other needs.Key words: morning papers, evening papers, webb magazines, young adults, surveillance, personal release/entertainment, personal identity and interactivity.</p>
523

Impact of Oxygen-Release Material on Human Urine-Derived Stem Cells’ Differentiation and Proliferation in Hypoxic Condition <em>In Vitro</em>

Krieg, Marie-Louise January 2010 (has links)
<p>One of today’s most widely spread health problems is urinary incontinence, affecting 60-80% of the US population from age 15 and up. Treatment based on the possibility to implant a scaffold seeded with the patients’ own urine-derived stem cells, hUSC, to regenerate the damaged muscle tissue, would prove effective. A main challenge in regenerating new tissue from cell-seeded scaffolds is the limited cell survival due to insufficient oxygen diffusion to the center of the scaffold. Ways of enhancing cell survival, and thereby, proliferation and differentiation, is by hypoxic preconditioning of the cells or implantation in an oxygen-release material. Hypoxic preconditioning has shown to enhance proliferation as well as the expression of vascular endothelial growth factor, VEGF, in for example human bone marrow derived stem cells, hBMSC. VEGF is involved in the establishment of vasculature structures and an upregulation of its expression may therefore help promote quicker angeogenisis, increasing the oxygen supply and the cell survival. Oxygen-release materials have shown to enhance cell survival and growth both <em>in vitro</em> and <em>in vivo</em>.<em></em></p><p>This study aims to investigate the effect of hypoxia on hUSC, during 9 days of hypoxic culturing (2.0% ± 0.1% O<sub>2</sub>) with and without oxygen-release material (PLGA 75:25 with 5 w% CPO) <em>in vitro</em>. hBMSC, and human smooth muscle cells, hSMC, have been used as control groups. Cell proliferation, morphology, differentiation, production of VEGF, and expression of hypoxia inducible factor HIF-1α have been studied.</p><p>According to the results, combining hypoxic preconditioning of hUSC with implantation in oxygen-release material could be an effective way to regenerate muscular tissue. Hypoxic preconditioning enhanced cell proliferation, production of VEGF, and HIF-1α expression. The increase of VEGF and HIF-1α would promote vascularization when implanted. The oxygen-release material showed possible promotion of cell differentiation, which would augment the hUSCs’ myogenic differentiation, while supplying oxygen until the tissue’s vascular structure has been established.</p>
524

Granulocyte Adhesion to Matrix Proteins and the Effect on the Release of Granule Proteins : Development of a Simple Method and its Application in Experimental and Clinical Studies

Xu, Xiaoyan January 2001 (has links)
<p>Granulocyte adhesion and release of their granule proteins are key steps during selective accumulation of a certain cell to an inflammatory site. Eosinophils are specifically recruited to sites of allergic inflammation and parasitic infection, whereas neutrophil influx predominates in bacterial infection and rheumatoid arthritis. </p><p>A simple, reliable and convenient method was developed for the measurement of granulocyte adhesion and release of granule proteins by using the normal population of granulocytes. The design allows simultaneous quantitative assessment of eosinophil and neutrophil adhesion to proteins and degranulation. </p><p>Using this method, manganese ions (Mn<sup>2+</sup>) induced a higher level of eosinophil adhesion to fibronectin, fibrinogen and albumin as compared with neutrophils. PMA induced comparable levels of eosinophil and neutrophil adhesion. F-MLP stimulated a rapid, short-term adhesion of neutrophils to fibrinogen. </p><p>In the same conditions PMA alone stimulated a dose-dependent release of ECP from cells that adhered to both fibronectin and fibrinogen. Meanwhile, Mn<sup>2+</sup> amplified the release of ECP induced by PMA. Furthermore, release of ECP was shown to be associated with cell death.</p><p>PMA, in combination with Mn<sup>2+</sup>, induced a marked release of ~ 80%of the intracellular content of lactoferrin and HNL in neutrophils. PMA or f-MLP alone induced 30-40% release of lactoferrin and HNL. A maximal release of MPO of 15-20% was obtained from neutrophils stimulated by PMA and Mn<sup>2+</sup>. Release of lactoferrin and HNL showed a significant negative relationship to the viability of cells.</p><p>Stimulated by PMA, eosinophils from pollen-atopic patients during early pollen season displayed a markedly enhanced adhesion and release of ECP of eosinophils compared with eosinophils from the references. Priming with IL-5 caused a significantly higher adhesion and release of ECP by eosinophils in response to PMA. GM-CSF priming enhanced eosinophil adhesion in response to PAF and PMA plus Mn<sup>2+</sup>, but did not enhance the release of ECP.</p><p>In conclusion, the assay allows a simple quantification of eosinophil and neutrophil adhesion, as well as degranulation by using the normal population of granulocytes. Cellular adhesion plays an important role in the regulation of both eosinophil and neutrophil degranulation, but adhesion and degranulation can be induced separately.</p>
525

The Influence of the Adenosine A<sub>1</sub>-receptor on Tubuloglomerular Feedback and Renin Release

Brown, Russell January 2004 (has links)
<p>The kidneys play a vital role in the maintenance of extracellular fluid and electrolyte balance and blood pressure. Adenosine, acting through the adenosine A<sub>1</sub>-receptor (A<sub>1</sub>R), and nitric oxide have been implicated in several of the regulatory mechanisms in the kidney. The A<sub>1</sub>R has been found to be present in the renal vasculature, primarily in the afferent arterioles, and in the proximal tubules. The tubuloglomerular feedback mechanism (TGF) is an important regulator of renal vascular tone and glomerular filtration rate. The aim of these investigations was to further elucidate the role of adenosine, acting through the A<sub>1</sub>R. Investigations on adenosine’s renal effects were performed on transgenic mice lacking the A<sub>1</sub>R.</p><p>TGF response, elicited by increased distal salt load, was completely abolished in the A1R knockout (A<sub>1</sub>R -/- ) mice. Basal plasma-renin levels were found to be ~2-fold higher in the A<sub>1</sub>R -/- compared to the A<sub>1</sub>R wild-type (A<sub>1</sub>R+/+) mice. However, salt intake induced inverse changes in plasma-renin levels, indicating that adenosine tonically inhibits macula densa stimulated renin release. Anesthetized and conscious A<sub>1</sub>R -/- mice, measured telemetrically, had an increased blood pressure, which could be due to the increased plasma-renin levels. Despite the high plasma-renin levels, increased urinary sodium excretion was also observed in the A<sub>1</sub>R -/- animals. Ischemia caused a decrease in renal function in both A<sub>1</sub>R+/+ and A<sub>1</sub>R -/- mice. Ischemic preconditioning protected the A<sub>1</sub>R+/+ mice from subsequent ischemic episode but had no protective effect on the A<sub>1</sub>R -/- mice.</p><p>Acute extracellular volume expansion greatly attenuates TGF sensitivity, thus facilitating the elimination of excess fluid. Acute inhibition of nNOS in volume-expanded rats was found to re-establish the attenuated TGF response caused by acute extracellular volume expansion.</p><p>The results show that adenosine, acting through the A<sub>1</sub>R, plays an important role in mediating TGF response and consequently, regulating renin release, blood pressure, electrolyte balance and other vital renal mechanisms.</p>
526

Spinal Acetylcholine Release : Mechanisms and Receptor Involvement

Kommalage, Mahinda January 2005 (has links)
<p>Impulses coming from peripheries are modified in the spinal cord and transmitted to the brain. Several neurotransmitters have been involved in the processing of impulses in the spinal dorsal horn. Acetylcholine (ACh) is one of many neurotransmitters involved in the regulation of nociception in the spinal cord. In this study we investigated the role of nicotinic, muscarinic, serotonergic and GABA receptors in the regulation of spinal ACh release since these receptors are reported to be involved in spinal nociceptive processes.</p><p>Different receptor ligands were infused intraspinally via microdialysis and the spinal ACh release was measured by on-line HPLC. Receptor-ligand binding studies were performed with spinal cord homogenates as well as receptors expressed in cells.</p><p>In the first study, we found that nicotine and some of the nicotinic antagonists used increased ACh release suggesting that spinal ACh release is regulated by different nAChRs. Nicotine and nicotinic agonists may act on different types of receptors with different affinity to produce the observed net effect of increased ACh release. We propose the possibility of an involvement of three different nicotinic receptor subtypes in the regulation of spinal ACh release. </p><p>The effect of epibatidine, which is regarded as a nicotinic agonist, on muscarinic receptors was investigated in the second study. We propose that epibatidine, in μM concentrations, is a partial muscarinic receptor agonist that may interact with spinal muscarinic receptors to increase ACh release. The dual action on both nAChRs and mAChRs may explain the potent analgesic effect observed after intra-spinal epibatidine administration.</p><p>In the third study, we investigated the role of serotonin receptor involvement in ACh release control. The results suggest that only 5-HT<sub>1A</sub> and 5-HT<sub>2A</sub> receptors are involved in spinal ACh release. Considering current knowledge, the most probable location of 5-HT<sub>2A</sub> receptors is on cholinergic neurones. On activation of the 5-HT<sub>2A</sub> receptors the cellular excitability of cholinergic neurones is increased which results in an increasing ACh release. The 5-HT<sub>1A</sub> receptors might be located on cell bodies of GABA neurones which inhibit the firing rate of the GABA neurones when activated by serotonin. </p><p>In the fourth study, we investigated the GABA receptor involvement in the regulation in spinal ACh release. We found that GABA<sub>A</sub> receptors are tonically inhibiting spinal ACh release. The results further suggest that GABA<sub>B</sub> receptors also are involved in the regulation of spinal ACh release. However, unlike GABA<sub>A</sub> antagonists, GABA<sub>B</sub> antagonists do not increase ACh release. This suggests that GABA<sub>B</sub> receptors are not tonically regulating the spinal ACh release. </p>
527

Prolonged Drug Release from Gels, using Catanionic Mixtures

Bramer, Tobias January 2007 (has links)
<p>The use of catanionic drug-surfactant mixtures was proven to be an efficient novel method of obtaining prolonged drug release from gels. It was shown that various commonly used drug compounds are able to form catanionic mixtures together with oppositely charged surfactants. These mixtures exhibited interesting phase behaviour, where, among other structures, vesicles and large worm-like or branched micelles were found. The size of these aggregates makes them a potential means of prolonging the drug release from gels, as only monomer drugs in equilibrium with larger aggregates were readily able to diffuse through the gel. When the diffusion coefficient for drug release from the formulation based upon a catanionic mixture was compared to that obtained for the drug substance and gel alone, the coefficient was some 10 to 100 times smaller.</p><p>The effects of changes in the pH and ionic strength on the catanionic aggregates was also investigated, and this method of prolonging the release was found to be quite resilient to variations in both. Although the phase behaviour was somewhat affected, large micelles and vesicles were still readily found. The drug release was significantly prolonged even under physiological conditions, that is, at a pH of 7.4 and an osmolality corresponding to 0.9% NaCl.</p><p>Surfactants of low irritancy, capric and lauric acid, may successfully be used instead of the more traditional surfactants, such as sodium lauryl sulfate (SDS), and prolonged release can still be obtained with ease.</p><p>Some attempts to deduce the release mechanism from the proposed systems have also been made using transient current measurements, dielectric spectroscopy, and modelling of the release using the regular solution theory. In these studies, the previous assumptions made concerning the mechanism responsible for the release were confirmed to a large extent. Only small amounts of the drug existed in monomer form, and most seemed to form large catanionic aggregates with the oppositely charged surfactant.</p>
528

Development and in vivo testing of novel hydrochlorothiazide gastric retention formulations in healthy volunteers and stage I hypertensive patients

Farid, Samar Farghali 06 May 2004 (has links)
This thesis describes in vitro and in vivo evaluation of a gastric retention formulation (GRF) developed at Oregon State University. The formulation was prepared from xanthan gum and locust bean gum as gelling agents and other formulation ingredients were added, then it was originally vacuum oven dried. The effect of freeze drying on GRF was studied in this research. Freeze dried GRF were evaluated for dissolution and drug release properties using hydrochlorothiazide as a model drug. The effect of storage of GRF inside hard gelatin capsules on rate of swelling of the capsule shell and release of GRF was also studied. Storage for up to 12 months had no effect on capsule shell swelling and release of GRF. Gastric residence time, pharmacokinetics and bioavailability of hydrochlorothiazide, a drug that has an absorption window limited to the upper small intestine, from two different sizes of gastric retention formulations (GRF) were evaluated in 12 healthy volunteers in both fed and fasted states, and compared to immediate release tablets. Extent of bioavailability of drug from the larger formulation in this study was comparable to IR tablets in both fed and fasted states. Deconvolved input functions data suggest that the GRF stayed in the stomach providing sustained drug input for 12-28 hours. Initial blood pressure lowering and side effects of hydrochlorothiazide from a gastric retention formulation were evaluated and compared to immediate release tablets in 10 subjects with stage I hypertension. Gastric retention formulations produced an average reduction in systolic blood pressure 3 mm Hg lower than IR tablets regardless of sequence of administration. GRF also produced less blood pressure fluctuation in most subjects than IR tablets. Most subjects reported fewer and less severe side effects with GRF than IR tablets. / Graduation date: 2004
529

Delivery of Etanidazole to Brain Tumor from PLGA Wafers

Tan, Wilson Hor Keong, Lee, Timothy, Wang, Chi-Hwa 01 1900 (has links)
This paper presents the computer simulation results on the delivery of Etanidazole (radiosensitiser) to the brain tumor and examines several factors affecting the delivery. The simulation consists of a 3D model of tumor with poly (lactide-co-glycolide) (PLGA) wafers of 1% Etanidzole loading implanted in the resected cavity. A zero-order release device will produce a concentration profile in the tumor which increases with time until the drug in the carrier is depleted. This causes toxicity complications during the later stages of drug treatment. However, for wafers of similar loading, such release results in a higher drug penetration depth and therapeutic index as compared to the double drug burst profile. The numerical accuracy of the model was verified by the similar results obtained in the two-dimensional and three-dimensional models. / Singapore-MIT Alliance (SMA)
530

Fabrication of Controlled Release Devices Using Supercritical Antisolvent Method

Lee, Lai Yeng, Smith, Kenneth A., Wang, Chi-Hwa 01 1900 (has links)
In this study, the supercritical antisolvent with enhanced mass transfer method (SASEM) is used to fabricate micro and nanoparticles of biocompatible and biodegradable polymer PLGA (poly DL lactide co glycolic acid). This process may be extended to the encapsulation of drugs in these micro and nanoparticles for controlled release purposes. Conventional supercritical antisolvent (SAS) process involves spraying a solution (organic solvent + dissolved polymer) into supercritical fluid (CO[subscript 2]), which acts as an antisolvent. The high rate of mass transfer between organic solvent and supercritical CO[subscript 2] results in supersaturation of the polymer in the spray droplet and precipitation of the polymer as micro or nanoparticles occurs. In the SASEM method, ultrasonic vibration is used to atomize the solution entering the high pressure with supercritical CO[subscript 2]. At the same time, the ultrasonic vibration generated turbulence in the high pressure vessel, leading to better mass transfer between the organic solvent and the supercritical CO₂. In this study, two organic solvents, acetone and dichloromethane (DCM) were used in the SASEM process. Phase Doppler Particle Analyzer (PDPA) was used to study the ultrasonic atomization of liquid using the ultrasonic probe for the SASEM process. Scanning Electron Microscopy (SEM) was used to study the size and morphology of the polymer particles collected at the end of the process. / Singapore-MIT Alliance (SMA)

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