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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.
51

Comandra Blister Rust

Olsen, Mary W., Young, Deborah 05 1900 (has links)
3 pp. / Mondell pine should not be planted within a mile of Comandra populations. Infection of pine occurs through needles by spores produced on Comandra, but spores produced on pine cannot re-infect pine. This article gives information about the disease cycle, the symptoms and prevention and control methods for blister rust.
52

An assessment of the HIV prevention needs of injection drug users in Montana

Cunningham, Nancy Mae. January 2007 (has links)
Thesis (Ph. D.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed Apr. 2, 2007. Includes bibliographical references (p. 87-92).
53

Microneedles for transdermal drug delivery in human subjects

Gupta, Jyoti 06 July 2009 (has links)
Microneedles have been developed as a minimally invasive alternative to painful hypodermic needles to deliver modern biotherapeutics. Previously, several in-vitro and in-vivo animal studies have been conducted to show that microneedles increase skin permeability to a wide range of molecules that cannot cross the skin using conventional transdermal patches due to the skin's stratum corneum barrier. However, only a limited number of studies have been performed to study microneedle-based drug delivery in human subjects. Therefore, the objective of this study was to perform the first-in-humans microneedle studies to: a) characterize skin repair responses to solid microneedle insertion to determine the extent of increased skin permeability coupled with predictions of pharmacokinetics of drug delivered through premeabilized skin, b) determine the effect of hollow microneedle-based infusion parameters on flow conductivity of skin and pain and thereby identify barriers to fluid flow into the skin from hollow microneedles, c) assess the safety and efficacy of systemic therapeutic effects through measurement of pharmacokinetic parameters, pain and irritation for microneedle-based insulin delivery in type 1 diabetes subjects, and d) assess the safety and efficacy of local therapeutic effects though delivery of lidocaine to the skin. Results showed for the first time that solid microneedle-treated skin reseals rapidly (< 2 h) in the absence of occlusion whereas occluded skin reseals slowly (3-40 h) depending on microneedle geometry as determined by skin impedance measurements. Increased microneedle length, number, and cross-sectional area led to slower recovery kinetics in the presence of occlusion. This thesis also demonstrated that the flow conductivity of skin decreased as fluid was infused to the dermis through hollow microneedles due to the dense structure of the dermis. Microneedle retraction, low flow rates, and the addition of hyaluronidase helped increase flow conductivity. Microneedles were able to deliver 800 µl of saline to the dermis without causing significant pain. Further, microneedle-based insulin delivery in type 1 diabetes subjects revealed that microneedles provided faster pharmacokinetics and improved glycaemic control than conventional subcutaneous catheters. Lastly, microneedle-based lidocaine injection demonstrated that microneedles were less painful, as effective, and more preferred than hypodermic needles in anesthetizing clinically relevant areas.
54

Rheological changes at the air-liquid interface and examining different kind of magnetic needles / Reologiska förändringar vid luft-vätskeskikt, samt utvärdering av olika sorters magnetiska nålar

Anderson, Fredrik January 2015 (has links)
The main objective in this work was to learn how the instrument, the Interfacial Shear Rheometer (ISR400), worked and to investigate how the rheological properties, storage modulus (elasticity), G' and loss modulus (viscous), G'', changes when the surface pressure at the air-liquid interphase changes. The second objective were to examine the different kind of magnetic needles used in the experiments and to conclude which type of needle is best for its specific field of analysis. It was concluded that the relative heavy needle with mass 70.6 mg and length 50 mm was best for systems where the viscous and elastic components are significantly large, where the inertia of the needle is not dominant. It also worked of using the heavier needle for a system of phospholipids. For the hydroxystearic acid (HSA) experiment that were tested on NaCl sub-phase there was a clear improvement after switching from the heavy needle (mass 41.5 mg; length 51 mm) to the relative lighter needle (mass 6.94 mg; length 34.7 mm). The values for the dynamic modulus therefore had a better agreement with reference literature. A spread layer of class II hydrophobins (HFBII) could be compressed to a surface pressure of 46 mNm-1. The G' and G'' values from the frequency sweep were discarded because the monolayer turned into a very viscous-like liquid, and the oscillating needle, after compression, was kind of stuck in the sub-phase and moved very staggering during a frequency sweep. The needle comparison experiment with silica particles 10 wt% Bindzil CC30 (BCC30), at pH 3.5 was done to see if there was any difference in the sensitivity for the needles at the interface which consisted of a pure 10 mM NaCl solution or a 10 mM NaCl solution with BCC30 added to it. The differences were negligible in terms of surface tension but there was a clear difference between the heavy needle and the light needle, when oscillating at higher frequencies (&gt;≈6 rad/s). With this study, the understanding of ISR400 has increased largely. Several issues have been addressed and the results provide a good basis for further studies within the many areas the instrument can be used for. Despite the project's time limit, and the fact that the instrument was new and untested where the project was carried out, focus areas were prioritized so good results could be achieved within reasonable goals. / Huvudmålet med detta arbete var att lära sig hur instrumentet ytskiktsreometern (ISR400) fungerade och undersöka hur de reologiska egenskaperna, elasticitetsmodulen G' och viskositetsmodulen G'', kommer att förändras när det sker en förändring för yttrycket vid gränsskiktet mellan luft och vätska. Det sekundära målet var att undersöka vilken typ av magnetiska nålar som är bäst att använda för respektive gränsskiktssystem. Av att använda den tyngre nålen med massan 70.6 mg och längden 50 mm kunde man dra slutsatsen att den är bäst att använda för system där de viskösa och elastiska komponenterna är signifikant stora, där nålens tröghet inte är dominant. Den fungerade även att mäta med i ett fosfolipidsystem. I experimentet med 12-hydroxy-stearinsyra (HSA) som utfördes på en subfas av NaCl, syntes en klar förbättring efter att byta från en tyngre nål (massa 41.5 mg; längd 51 mm) till en lättare (massa 6.94 mg; längd 34.7 mm). Värdena för dynamiska modulen stämde därför bättre överens med referenslitteraturen. Det utspridda lagret av klass II hydrophobins (HFBII) kunde komprimeras upp till yttrycket 46 mNm-1. Värdena för G' och G'' förkastades därför att monolagret förvandlades till en väldigt viskösliknande vätska, och den oscillerande nålen, efter kompressionen, satt fast i denna tröga vätska och rörde sig väldigt hackigt och oregelbundet under tiden ett frekvenssvep utfördes. Då en jämförelse av olika typer av nålar genomfördes med kiseldioxidpartiklar (10 % (viktsprocent) Bindzil CC30 med pH 3.5), för att se om det är någon skillnad i känslighet för nålarna vid gränssnittet, som bestod av en ren 10 mM NaCl-lösning eller en 10 mM NaCl-lösning med tillsatt BCC30. Skillnaderna var försumbara gällande ytspänningen, men det var en klar skillnad mellan den tunga nålen och den lätta nålen vid oscillering vid höga frekvenser (&gt;≈6 rad/s). I och med detta arbete så har förståelsen för hur ISR400 fungerar förbättrats mycket sedan starten. Flera frågeställningar har behandlats och resultaten ger en bra grund för fortsatta studier inom de många områden som utrustningen kan användas till. Trots projektets tidsbegränsning, och det faktum att instrumentet var nytt och oprövat på platsen där detta arbete utfördes, så prioriterades fokusområden så att goda resultat kunde uppnås inom rimliga mål.
55

Comparison between lichen, conifer needles, resin-based passive air sampling devices (PASDs), and snow to monitor semi-volatile organic compounds (SOCs) in the atmosphere /

Schrlau, Jill E. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.
56

Assessing industrial pollution by means of environmental samples in the Kemi-Tornio region

Pöykiö, R. (Risto) 29 November 2002 (has links)
Abstract The results of the comparison of various dissolution methods for sulphur showed, that HNO3 together with H2O2 gave more complete decomposition of organic components than HNO3 alone. The acid procedure with a mixture of HNO3+H2O2 slightly underestimated the S concentrations of plant material. The losses of sulphur were the highest in the dry ashing digestion procedure (HF(DAC)). The Leco combustion technique with infrared (IR) detection gave good precision and accuracy for sulphur. For the determination of heavy metals in plant materials, both the HNO3 and HNO3+H2O2 procedures were especially effective for determining Cr. However, the HNO3+HClO4 procedure gave lower results, and HF and HF(DAC) procedures greater values for Cr. Sulphur accumulation in pine needles around the pulp and paper mills was clearly higher than other points in the Kemi area. For example, within a radius of about 1-1.5 km around the mills of Oy Metsä-Botnia Ab Kemi Mills, the sulphur concentrations for (C) and (C+1) needles were 28 % and 26 % higher than those in the corresponding background samples collected in Kuivaniemi at a distance about 25 km from Kemi. Pine needles do not appeared to be appropriate a method for monitoring the accumulation of Fe, Zn, V and Pb emitted from pulp and paper mills. However, the Ca concentrations in (C+1) needles in the vicinity of the Oy Metsä-Botnia Ab Kemi Mills was 48 % higher than the average Ca concentration calculated from all (C+1) needles; thus it is likely that part of the Ca in the needles is derived from the mills. The regional distribution pattern of Cr and Ni in mosses in the Kemi-Tornio area in 2000 showed clearly that the most polluted area (Cr > 200 μg/g and Ni > 20 μg/g) appeared to lie within a few kilometres of the ferrochrome and stainless steel works of AvestaPolarit Stainless Oy. Within this area, the Cr concentrations in mosses were 4-13 times higher than those outside the urban area of Tornio. The area most polluted by the opencast chromium mining complex (Cr > 200 μg/g and Ni &lt; 20 μg/g) appeared to be in the immediate vicinity of complex. All the 95th percentile values for TSP (total suspended particles) in the mine area of AvestaPolarit Chrome Oy Kemi Mine were below the current Finnish air quality limit value of 300 μg/m3. However, the 98th percentile value exceeded the Finnish air quality guideline value of 120 μg/m3 at one monitoring site. According to leaching studies, the sum of calculated annual airborne pollution impact of water-soluble fraction (H2O) and environmentally mobile (CH3COONH4) fraction from the AvestaPolarit Chrome Oy Kemi Mine was Cr 1.2 kg, Fe 29 kg, Cu 63 kg, Ni 2.5 kg and Cd &lt; 100 mg. According to the homogeneity studies of heavy metal deposition on TSP filters, Cr, Ni, Cu and Fe were non-uniformly distributed over the glass fibre filters. The rsd values varied between 5.4-33.9 % for Cr, between 7.5-35.0 % for Ni, between 3.6-25.9 % for Cu, and between 6.6-19.9 % for Fe.
57

Vliv zvýšené koncentrace oxidu uhličitého na aktivitu a obsah enzymu Rubisco ve slunných a stinných jehlicích smrku ztepilého / Influence of elevated carbon dioxide concentration at Rubisco activity and its content in sunny and shaded needles of Norway spruce

Šibravová, Lenka January 2009 (has links)
Diploma thesis’s aim was to determine Rubisco activity and its content in sunny and shaded needles of Norway spruce (Picea abies [L.] Karst.) and confirm or refuse acclimation on Rubisco enzyme level. Samples were taken on the Experimental ecology station Czech Academy of Sciences at Bílý Kříž (Beskydy Mountains) where needles were cultivated in two cultivation spheres with different concetrations CO2. One cultivation sphere contains atmosphere with ambient (A) concentration CO2 (350 mol CO2 mol-1) and the other contains atmosphere with elevated (E) concentration CO2 (700 mol CO2 mol-1). Rubisco activities were determinated spectrophotometric, Rubisco content was determined by SDS-PAGE method. Samples were taken in the modele of June and in the end of September. Elevated concetration CO2 did not have significant influence on Rubisco activity. Whereas different exposition had significant influence on Rubisco activity in June, when was found lower Rubisco activity in shaded needles than in sunny needles. In September were not find significant differences in Rubisco activity beetwen sunny and shaded needles. We did not find statistically significant differences in Rubisco content between A and E needles in June. Incontrary, we found about 34 % lower Rubisco content in E needles than in A needles, which confirms acclimation on Rubisco enzyme level. In September Rubisco content was several time higher than in June, which evidences the long term building photosynthetic apparatus in coniferous trees.
58

Omvårdnadsåtgärder för att lindra lidande hos barn vid venprovtagning och PVK-sättning

Sjölander, Alma, Magnusson, Klara January 2023 (has links)
Bakgrund: Nålrelaterade procedurer är vanligt förekommande inom barnsjukvården och är något som orsakar lidande för barn. Om detta lidande inte förebyggs eller lindras adekvat kan det leda till stickrädsla. Sjuksköterskan har en skyldighet att vidta omvårdnadsåtgärder utefter barnets behov och därför är det viktigt att sjuksköterskan besitter kunskap om vilka omvårdnadsåtgärder som lindrar lidande hos barn vid venprovtagning och insättning av perifer venkateter (PVK-sättning). Syfte: Att beskriva omvårdnadsåtgärder som lindrar lidande hos barn vid venprovtagning och PVK-sättning. Metod: Litteraturstudien baserades på 14 kvantitativa originalartiklar som har kvalitetsgranskats. Resultatet har därefter analyserats genom att identifiera data, organisera data i olika kategorier samt summera och analysera detta, vilket resulterade i tre huvudkategorier: fysisk distraktion, aktiv distraktion och passiv distraktion. Resultat: Litteraturstudiens resultat visade att fysisk distraktion hade en lindrande effekt på smärta, oro och rädsla i samband med venprovtagning och PVK-sättning i ett flertal av studierna. Likaså hade aktiva och passiva distraktionsmetoder en betydande positiv effekt hos barnen i samband med procedurerna. Slutsats: Med hänsyn till distraktionsmetodernas påvisade effekt bör sjuksköterskan individanpassa omvårdnadsåtgärder och använda sig av dessa distraktionsmetoder i samband med venprovtagning och PVK-sättning. / Background: Needle related procedures are common in pediatric healthcare and causes suffering to the child. If this suffering is not adequately prevented or treated, a fear of needles could be developed. The nurse is responsible to take nursing measures according to the child's needs. Thus, it is important that the nurse has knowledge of which nursing measures that relieves suffering in children during venipuncture and intravenous insertion (IV-insertion). Aim: To describe nursing measures that relieve suffering in children during venipuncture or IV-insertion. Method: The literature study was based on 14 original quantitative articles. The articles were quality reviewed and then analyzed. The analysis consisted of identifying data, organizing and categorizing data and then summarizing and analyzing the result. The result was presented in three main categories: physical distraction, active distraction and passive distraction. Result: It was found that physical distraction had a relieving effect on pain, anxiety and fear during and after the venipuncture and IV-insertion in several studies. Likewise, active and passive distraction methods had a positive effect on the children during and after the procedure. Conclusion: Considering the effect of the distraction methods, the nurse should individualize the nursing measures during venipuncture and IV-insertion.
59

Morphological Studies of Crystallization in Thin Films of PEO/PMMA Blends

Okerberg, Brian 21 October 2005 (has links)
Morphological development during crystallization of thin films of poly(ethylene oxide) (PEO) / poly(methyl methacrylate) (PMMA) blends has been reported. Studies have focused on the effects of the blend composition, PMMA molecular weight, film thickness, and crystallization temperature on the observed crystal morphology. As the blend composition was varied from 90 to 30 wt% PEO, the crystal morphology varied from spherulites to needles and dendrites. Variation of the crystallization temperature and PMMA molecular weight resulted in similar changes in morphology. A morphological map demonstrating the roles of the experimental controls on the observed crystal morphology has been developed. This map was used as a tool for more detailed studies of the observed morphologies and morphological transitions. The dendritic region of the map (~ 30 = 40 wt% PEO) was studied in detail. Changes in the diffusion length were achieved through variation of the PMMA molecular weight, and were shown to influence the secondary sidebranch spacing. Sidebranch spacing measurements revealed that coarsening of the dendritic microstructure occurred well after the competition between diffusion fields of neighboring dendrite arms vanished, indicating the existence of another coarsening mechanism. These studies of dendritic sidebranching indicate that polymer dendrites develop by mechanisms similar to those in small molecules and metals. A number of in-situ observations of morphological transitions have also been reported, including a dense-branched morphology (DBM)/dendrite transition, a DBM/stacked-needle/needle transition, and a transition from dendrites with 90o sidebranching to dendrites with 45o branching or a dense-branched morphology, both of which grow at 45o to the original dendrite trunk. The DBM/dendrite transition occurred over a range of crystallization temperatures, indicating that the transition is not sharp. Crystal growth rate measurements verified this result. The DBM/stacked-needle/needle transitions demonstrated distinct jumps in the crystal growth rate, indicating a change in the growth mechanism or direction. For the transition involving a change in the growth direction, the effective level of noise (fluctuation) was found to be important in morphological selection. The results of this work have helped to define new directions for the study of crystal morphologies, especially in the areas of spherulite formation and dendritic growth. / Ph. D.
60

An investigation of safety syringes in the prevention of needlestick injuries

Kroes, Gabriel 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Daily more than 300 000 health care workers in South Africa are to a lesser or greater extent exposed to the risk of deadly viruses which can be transferred through neediestick injuries. It is estimated that currently 9,8 million people in South Africa are HIV positive. This high incidence of HIV has a great impact on the danger of infection from neediestick injuries. It is estimated that 44 000 neediestick injuries takes place annually in South Africa. Despite such a high risk there are currently few safety regulations or official efforts to prevent or determine the true impact and incidence of needlesticks in South Africa. This study project investigated the number of neediestick injuries that could potentially be prevented by the use of needles with safety features and estimated the ranges of benefits and costs of using such safety devices. With the financial constraints that are imposed on South African hospitals, infection control through the use of safety syringes makes economic sense. Prevention of infections is clearly far cheaper than cure. / AFRIKAANSE OPSOMMING: Daagliks word meer as 300 000 gesondheids personeel in Suid Afrika in 'n mindere of meerdere mate blootgestel aan die risiko van lewens gevaarlike viruse wat deur middel van naaldprik ongelukke oorgedra kan word. Hierdie risiko word spesifiek in Suid Afrika verhoog deur die hoë insidensie van HIV. Dit word beraam dat daar tans 9,8 miljoen mense in Suid Afrika is wat HIV positief is. Daar word beraam dat daar tans 44 000 naaldprik ongelukke per jaar in Suid Afrika plaasvind. Ten spyte van die hierdie hoë risko is daar tans min veiligheids regulasies of amptelike pogings om die omvang en voorkoming van naaldprik insidente te bepaal nie. Hierdie studie het die getal naaldprikke wat voorkom kan word deur die gebruik van veiligheids inspuitnaalde ondersoek en het die voordele en kostes van sulke veiligheidsmaatreëls beraam. Gegewe die finasiële druk wat ons tans in Suid Afrikaanse hospitale ondervind, is bewys dat die gebruik van veiligheids inspuitnaalde ekonomiese sin maak. Voorkoming op hierdie manier is bewys as 'n ver goedkoper opsie as nasorg.

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