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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.
91

Acupuncture for labour pain

Vixner, Linda January 2015 (has links)
Background: Acupuncture involves puncturing the skin with thin sterile needles at defined acupuncture points. Previous studies are inconclusive regarding the effect of acupuncture on labour pain, but some studies have found a reduction in the use of pharmacological pain relief when acupuncture is administered. The appropriate dose of acupuncture treatment required to elicit a potential effect on labour pain has not been fully explored. The dose is determined by many different factors, including the number of needles used and the intensity of the stimulation. In Sweden, manual stimulation of the needles is common practice when acupuncture is used for labour pain, but electrical stimulation of the needles, which gives a higher dose, could possibly be more effective. The overall aim of this thesis was to evaluate the effectiveness of acupuncture with manual stimulation (MA) of the needles as well as acupuncture with a combination of manual and electrical stimulation (EA) in reducing labour pain, compared with standard care without any form of acupuncture (SC). Methods: The study was designed as a three-armed randomised controlled trial in which 303 nulliparous women with normal pregnancies were randomised to MA, EA, or SC. The primary outcome was labour pain, assessed using the Visual Analogue Scale (VAS). Secondary outcomes were relaxation during labour, use of obstetric pain relief, and associations between maternal characteristics and labour pain and use of epidural analgesia respectively. Also, labour and infant outcomes, recollection of labour pain, and maternal experiences, such as birth experience and experience of the midwife, were investigated two months after the birth. The sample size calculation was based on the potential to discover a difference of 15 mm on the VAS. Data were collected during labour before the interventions, the day after birth, and two months later. Besides using the VAS, information was collected by means of study specific protocol, questionnaires and medical records. Results: The mean VAS scores were 66.4 in the MA group, 68.5 in the EA group, and 69.0 in the SC group (mean differences: MA vs. SC 2.6 95% CI -1.7 to 6.9, and EA vs. SC 0.6 95% CI -3.6 to 4.8). Other methods of pain relief were used less frequently in the EA group, including epidural analgesia, MA 61.4%, EA 46%, and SC 69.9%. (EA vs. SC OR 0.4 95% CI 0.2 to 0.7). No statistically significant differences were found in the recollection of labour pain between the three groups two months after birth (mean VAS score: MA 69.3, EA 68.7 and SC 70.1). A few maternal characteristics were associated with labour pain (age, dysmenorrhea, and cervix dilatation), but none of the investigated characteristics predicted the outcome of the acupuncture treatment in MA or EA. Women in the EA group experienced acupuncture as being effective for labour pain to a higher extent than women who received MA, MA 44.4%, EA 67.1% (EA vs. MA OR 2.4 95% CI 1.2 to 4.8). Women in the EA group also spent less time in labour (mean 500 min) than those who received MA (mean 619 min) and SC (mean 615 min) (EA vs. MA HR 1.4 95% CI 1.0 to1.9, EA vs. SC HR 1.4, 95% CI 1.1 to 2.0), and had less blood loss than women receiving SC, (EA vs. SC OR 0.1 95% CI 0.3 to 0.7). The women’s assessment of the midwife as being supportive during labour (MA 77.2%, EA 83.5%, SC 80%), overall satisfaction with midwife care (MA 100%, EA 97.5%, SC 98.7%), and having an overall positive childbirth experience (MA 64.6%, EA 61.0%, SC 54.3%) did not differ statistically. No serious side effects of the acupuncture treatment were reported. Conclusion: Acupuncture, regardless of type of stimulation, did not differ from standard care without acupuncture in terms of reducing women’s experience of pain during labour, or their memory of pain and childbirth overall two months after the birth. However, other forms of obstetric pain relief were less frequent in women receiving a combination of manual and electrical stimulation, suggesting that this method could facilitate coping with labour pain.
92

Assessing the risks of serious adverse events from regular long-acting beta-agonists for adults and children with asthma

Cates, Christopher Joseph January 2011 (has links)
No description available.
93

NMR and MRI studies of controlled release drug delivery systems

Zhang, Qilei January 2012 (has links)
No description available.
94

Προσαρμοστικός έλεγχος μεταβλητών συστημάτων / Adaptive control of varying systems

Νικολακόπουλος, Γεώργιος 25 June 2007 (has links)
Η παρούσα διδακτορική διατριβή στοχεύει στην μελέτη και ανάλυση μεταβλητών συστημάτων με απώτερο σκοπό την ανάπτυξη αλγορίθμων στο χώρο της αναγνώρισης συστημάτων, πρόβλεψης εξόδου αυτών, και δημιουργίας προσαρμοστικών ελεγκτών που θα επιδεικνύουν σθεναρότητα απέναντι στις μεταβολές των υπό μελέτη συστημάτων. Η μεταβολή στα συστήματα αυτά προκύπτει κυρίως από την εισαγωγή τυχαίων χρονικών καθυστερήσεων στην είσοδο και στην έξοδο αυτών. Οι καθυστερήσεις αυτές, είναι δυνατόν να είναι σταθερές ή μεταβαλλόμενες, γνωστές ή άγνωστες, ντετερμινιστικές ή στοχαστικές. Σαν τελικό αποτέλεσμα οι εισαγόμενες χρονοκαθυστερήσεις είναι δυνατόν να αλλάξουν την συμπεριφορά του συστήματος οδηγώντας αυτό στην αστάθεια. Στην παρούσα διδακτορική διατριβή προτείνονται μέθοδοι μοντελοποίησης αυτών των χρονοκαθυστερήσεων σε συνδυασμό με τους αλγορίθμους αναγνώρισης και πρόβλεψης εξόδου συστημάτων υποκείμενων σε αυτές τις χρονικές καθυστερήσεις. Επιπροσθέτως παρατίθενται πρότυπες και κατάλληλα διαμορφωμένες δομές προσαρμοστικού ελέγχου και μελέτης της ευστάθειας αυτών των συστημάτων. / The aim of this dissertation is the study and analysis of varying systems, as also the development of algorithms in the field of: a) system identification, b) system prediction, and c) adaptive control that will be able to be robust to the variations of the systems under study. These variations in these systems are induced mainly from the insertion of time delays in the input and output of those systems. These delays can be constant, or varying, known or unknown, deterministic or stochastic. As a final result these time delays can alter the behavior and the performance of the system while driving it to instability. In this dissertation new algorithms are proposed for the modeling of these time delays in conjunction with the algorithms for the identification and output prediction of systems with time delays. Additionally new algorithms of adaptive control and stability analysis of the controlled systems are proposed.
95

Advanced Technologies for Fabrication and Testing of Large Flat Mirrors

Yellowhair, Julius Eldon January 2007 (has links)
Classical fabrication methods alone do not enable manufacturing of large flat mirrors that are much larger than 1 meter. This dissertation presents the development of enabling technologies for manufacturing large high performance flat mirrors and lays the foundation for manufacturing very large flat mirrors. The enabling fabrication and testing methods were developed during the manufacture of a 1.6 meter flat. The key advantage over classical methods is that our method is scalable to larger flat mirrors up to 8 m in diameter.Large tools were used during surface grinding and coarse polishing of the 1.6 m flat. During this stage, electronic levels provided efficient measurements on global surface changes in the mirror. The electronic levels measure surface inclination or slope very accurately. They measured slope changes across the mirror surface. From the slope information, we can obtain surface information. Over 2 m, the electronic levels can measure to 50 nm rms of low order aberrations that include power and astigmatism. The use of electronic levels for flatness measurements is analyzed in detail.Surface figuring was performed with smaller tools (size ranging from 15 cm to 40 cm in diameter). A radial stroker was developed and used to drive the smaller tools; the radial stroker provided variable tool stroke and rotation (up to 8 revolutions per minute). Polishing software, initially developed for stressed laps, enabled computer controlled polishing and was used to generate simulated removal profiles by optimizing tool stroke and dwell to reduce the high zones on the mirror surface. The resulting simulations from the polishing software were then applied to the real mirror. The scanning pentaprism and the 1 meter vibration insensitive Fizeau interferometer provided accurate and efficient surface testing to guide the remaining fabrication. The scanning pentaprism, another slope test, measured power to 9 nm rms over 2 meters. The Fizeau interferometer measured 1 meter subapertures and measured the 1.6 meter flat to 3 nm rms; the 1 meter reference flat was also calibrated to 3 nm rms. Both test systems are analyzed in detail. During surface figuring, the fabrication and testing were operated in a closed loop. The closed loop operation resulted in a rapid convergence of the mirror surface (11 nm rms power, and 6 nm rms surface irregularity). At present, the surface figure for the finished 1.6 m flat is state of the art for 2 meter class flat mirrors.
96

Clinical and endocrine responses to ovarian hyperstimulation in flare and and luteal gonadotropin-releasing hormone agonist (GnRHa) protocols

Nguyen, Tuan-Anh T 11 1900 (has links)
Background: Due to the “flare effect” associated with the flare protocol, variation in the degree of follicular maturation during stimulation may result in differences in follicle response as compared to the luteal protocol which is based on maximal pituitary suppression and synchronization of follicular maturation. In this study, besides other methods, Anti-Mullerian Hormone (AMH), a novel marker for ovarian reserve, was used as a tool to evaluate the ovarian responsiveness to stimulation. Methods: Women undergoing IVF/ICSI treatment in the UBC IVF Program from January to December 2006 using luteal and flare protocols were retrospectively selected for a total of 40 treatment cycles, 20 cycles in each protocol matched by age, weight, and indication for IVF/ICSI. Serial serum Estradiol (E₂) levels and follicle data were obtained from the clinic chart. Follicle stimulating hormone (FSH), Luteinizing Hormone (LH), progesterone (P), androstenedione (D₄) and AMH levels were measured from aliquots of frozen serum samples. Hormone responses were evaluated by Area Under the Curve (AUC). Data were analyzed using the t-test and statistical significance was considered present at P<0.05. Results are reported as the mean ± SEM. Results: For flare versus luteal protocol, there was a significant difference in the number of total follicles (14.5 ± 1.8 vs 21.3 ± 2.3), medium follicles (3.7 ± 0.6 vs 8.4 ± 1.3), eggs retrieved (8 ± 0.8 vs 14 ± 1.4) and oocytes fertilized (4.4 ± 0.5 vs 8.4 ± 0.7), AMH AUC (62 ± 12 vs 111 ± 13), LH AUC (67 ± 21 vs 20 ± 9), FSH AUC (171 ± 59 vs 112 ± 29), respectively. Mean number of embryos transferred in both groups was similar. Number of pregnancies conceived (5 for flare and 10 for luteal protocol) was not significantly different. Although E₂ AUC in luteal protocol was higher than that in flare protocol, the difference was not statistically significant (28,339 ± 2,669 vs 26,905 ± 2,790). Differences in P and D₄ AUC between the two protocols were not statistically significant. Correlations with ovarian follicles and eggs retrieved were better for AMH than E₂. Conclusions: The luteal protocol exhibited a better ovarian response to stimulation as compared to the flare protocol. As compared to E₂, AMH had a better correlation with the number of follicles and eggs retrieved.
97

DEVELOPMENT AND EVALUATION OF BOUNDARY OBJECTS IN THE HETEROGENEOUS DOMAIN OF COMPLEX CHRONIC CONDITIONS

Sampalli, Tara 19 July 2011 (has links)
Complex and chronic health conditions with multiple diagnoses and lacking in clinical practice guidelines often require a multidisciplinary care management scheme. Research has shown that the domain knowledge for these conditions is multidisciplinary, inconsistent, nonstandardized and poorly categorized making them heterogeneous and consequently challenging for collaborative work. The application of the boundary objects approach has come to the forefront as a way of closing communication gaps in collaborative work. There are limited research efforts in the application of boundary objects in the health care field and almost none in the area of complex chronic conditions. Research investigation of the application of boundary objects in heterogeneous domains is also limited. The primary objective(s) of this thesis is (are) to develop, test and evaluate a model and a methodology for creating boundary objects in the heterogeneous domain of complex chronic conditions. The methodology in this research applies a two-staged approach for enabling interoperability in the domain. The first stage is the development of a controlled vocabulary as a boundary object and the second stage of the two-staged approach is the development of an ontology as a boundary object to generate syntactic, semantic and pragmatic levels of interoperability in the dynamic domain. Towards these objectives, the boundary objects developed in the study satisfy certain unique requirements, namely to, have pragmatic boundaries, be dynamic in nature and be in standardized forms. To the best of our knowledge, this research is the first to investigate the development of boundary objects in the heterogeneous domain of complex chronic conditions. The outcome of this research is the development of a model for the generation of boundary objects to enhance communication among multidisciplinary clinicians. The model is developed in the heterogeneous domain of two complex chronic health conditions, namely, multiple chemical sensitivity and chronic pain. A testing and an evaluation process conducted in this research demonstrates that a high percentage of clinicians (>80%) agree on the overall usefulness of the boundary objects developed in this research. The results from the research are promising in terms of the potential applications of boundary objects in closing communication gaps in the multidisciplinary management of complex conditions.
98

Atom transfer radical polymerization with low catalyst concentration in continuous processes

Chan, Nicky 30 April 2012 (has links)
Atom transfer radical polymerization (ATRP) is a dynamic technique that possesses tremendous potential for the synthesis of novel polymeric materials not possible through conventional free radical polymerization. However, its use on an industrial scale has been limited by the high level of transition metal complex required. Significant advances have been made in the last 5 years towards lowering the level of copper complexes used in ATRP, resulting in novel variants called “activator regenerated by electron transfer” (ARGET) and “single electron transfer-living radical polymerization” (SET-LRP). To fully realize the potential of ATRP, its use in industrially relevant processes must be studied. Continuous processes such as tubular flow reactors and stirred tank reactors (CSTR) can reduce waste, improve productivity and facilitate process scale-up when compared to common batch reactors. The combination of low copper concentration ATRP techniques and continuous processes are especially attractive towards the design of a commercially viable process. This thesis presents a study into ARGET ATRP and SET-LRP as applied to continuous tubular and stirred tank reactors for the production of acrylic and methacrylic polymers. The equilibrium which governs polymerization rate and control over molecular architecture is studied through batch ARGET ATRP experiments. The improved understanding of ARGET ATRP enabled the reduction of ligand from a 3 to 10 fold excess used previously down to a stoichiometric ratio to copper salts. ARGET ATRP was then adapted to a continuous tubular reactor, as well as to a semi-automated CSTR. The design of the reactors and the effect of reaction conditions such as reducing agent concentration and residence time are discussed. The use of common elemental copper(0) such as copper wire and copper tubing is also investigated with SET-LRP for room temperature polymerization of methyl acrylate. SET-LRP is adapted to a CSTR to observe the effects of residence time on reaction rate, molecular weight control as well as copper consumption rate. The use of copper tubing as a catalyst source for SET-LRP is demonstrated and the design of a continuous tubular reactor using a combination of copper and stainless steel tubing is discussed. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2012-04-30 16:01:28.916
99

A randomized controlled trial of storytelling as a communication tool aimed at parents of children presenting to the emergency department with croup

Hartling, Lisa Unknown Date
No description available.
100

A Randomized Controlled Trial Evaluating Lanolin for the Treatment of Nipple Pain Among Breastfeeding Women

Allen, Kimberley Teresa 16 July 2014 (has links)
It is widely accepted that breast milk is the optimal source of infant nutrition. Despite the World Health Organization (WHO) recommendation of exclusive breastfeeding for the first 6 months of infant life, many women discontinue breastfeeding as a result of perceived difficulties. Nipple pain is a highly prevalent, significant reason for breastfeeding cessation. Among the numerous interventions for nipple pain, the application of lanolin is commonly recommended, with endorsement by Health Canada, The La Leche League, and International Board Certified Lactation Consultants. The few studies that have evaluated the effectiveness of lanolin on nipple pain have lacked methodologic rigor, and are thus not reliable or generalizable. As such, the purpose of this trial was to rigourously evaluate the effect of lanolin for the treatment of nipple pain among breastfeeding women. This single-site randomized controlled trial (RCT) compared the application of lanolin (treatment) to usual postpartum care (not applying lanolin) for the treatment of nipple pain. The primary outcome for this trial was the effect on pain severity, as measured by a numeric rating scale (NRS) at 4 days post-randomization. Of 186 participants, 93 were randomized to the treatment group and 93 to the usual care group. At 4 and 7 days post-randomization there were no statistically significant differences in pain scores between groups. It is noteworthy that by 7 days post-randomization there were clinically relevant decreases in nipple pain in both groups. However, there were no statistically significant differences between groups for other outcomes, including pain measured with the short-form McGill Pain Questionnaire, breastfeeding duration, breastfeeding exclusivity, and breastfeeding self-efficacy. Despite these findings, women in the treatment group were significantly more satisfied receiving lanolin for their nipple pain than those receiving usual care. Since the use of lanolin is no more effective than applying nothing to the nipples for the management of nipple pain, the widespread use of lanolin is questionable. Further research is required on the role of interventions to prevent nipple pain and damage, and the effect of anticipatory guidance on improving breastfeeding outcomes for those experiencing nipple pain in the early postpartum period.

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