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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.
351

Newborn Country: Space, Place, and the Rise of Neonatal Intensive Care in the United States, 1930–1980

Bergen, Sadie January 2025 (has links)
This dissertation examines how newborn medical care was institutionalized in hospitals across the United States between 1930 and 1980. Over that time, newborn medicine evolved from a relatively neglected domain of pediatrics into one of its most crowded arenas, anchored by new neonatal intensive care units (NICUs) where round-the-clock, high-tech care was provided to critically ill and premature newborns. Rather than focusing on therapeutic developments, “Newborn Country” uses space and place as analytic optics to understand the rise of the NICU. It argues that the course of newborn medicine was set in the process of answering questions about how to construct safe hospital environments for newborns and how to distribute specialized newborn care across a fragmented national landscape of hospital-centric medicine. Specific techniques of governance, from infection control protocols to health planning agendas, as well as their uneven and often unequal application, structured the spaces of promised health and healing that American newborns and their caretakers have moved through. The transition of birth from the home to the hospital demanded new spaces for newborn care, the safety of which were quickly cast into question by epidemics of hospital-associated infections. The organized response to these infections relied on the reallocation of hospital space through a gendered paradigm of aseptic discipline, but this paradigm fell apart in the face of hospital spaces defined by regimes of socioeconomic and racial segregation. In the 1950s, antibiotic-resistant infections in hospital nurseries challenged prevailing infection control strategies, exposing the porous boundaries between hospital environments and their surrounding communities and encouraging institutions to surveil their built and social ecosystems more actively. As antibiotic-resistant nursery infections waned in virulence in the early 1960s, freedom from the threat of infection opened the possibilities for newborn care. It facilitated new arrangements of space, labor, and neonatal patients that challenged norms of hospital safety but held immense promise for saving newborn lives. “Newborn Country” also considers the politics of organizing and distributing specialized newborn care, beginning with systems of emergency transport organized for premature infants in the 1930s and 1940s. Both emergency medical services and specialized newborn care were caught up in a wave of enthusiasm for “regionalizing” medical services within defined geographic areas in the 1960s. Hospitals enacted “perinatal regionalization” by creating hierarchical networks of care connected by a circulatory system of newborn transportation. In the 1970s, perinatal regionalization remade geographies of care under the new banner of perinatal health. As the decade came to a close and NICUs were increasingly identified as a source of institutional profit and prestige, perinatal regionalization became a contested stage for the spatial politics of allocating hospital resources.
352

GEOSPATIAL MODELLING OF PRAIRIE RIVERS: LINKING PHYSICAL INDICATORS OF FISH HABITAT TO LARGE SCALE GEOMORPHIC PATTERNS IN RIVER SYSTEMS USING GEOMORPHIC RESPONSE UNITS (GRU)

2015 January 1900 (has links)
Rivers are inherently dynamic environments with fluctuations in water quality, hydrology, connectivity and geomorphology. Though geomorphology has long been recognized as an important driver defining biological, ecological, and physical habitat characteristics of rivers, a readily applied classification tool that links such characteristics has been lacking. The Geomorphic Response Unit (GRU) method provides a novel approach to identifying large scale patterns in geomorphic character that provide a link between the hydrological regime and different habitat types to which species respond. Specifically, I investigated whether Geomorphic Types and GRUs are related to the distribution and abundance of different fish species, reflecting unique physical habitat characteristics of individual GRUs. The thesis chapters are manuscript based. The second chapter identifies relationships between specific Geomorphic Types, identified using the Geomorphic Response Unit (GRU) methodology, and Lake Sturgeon overwintering locations in the South Saskatchewan and Saskatchewan Rivers. Habitat selection ratios suggest that Lake Sturgeon in the Upper South Saskatchewan River significantly selected for one of seven possible Types for overwintering. Logistic regression results found both Type 0 and Type 4 predicted significantly higher Sturgeon presence than all other Types (P = < 2e-16 for both). The third chapter examines relationships between GRUs and abundance of both mature and immature Carmine Shiner in the Birch River, Manitoba. Differences in the median mature Carmine Shiner CPUEs among the GRUs are not statistically different (Kruskal-Wallis test H =1.723; df = 3, p value = 0.632), though interesting qualitative relationships were identified which may inform further studies. The fourth chapter investigates whether GRUs derived using a large scale network approach are linked to the abundance of specific fish species in the Assiniboine River, Manitoba. A Kruskal-Wallis test identified significant differences in CPUE among GRUs for 10 of 14 tested species. Post-hoc pairwise multiple comparisons using Dunn’s Method with Bonferroni p-value correction for multiple paired tests isolated the GRUs that were different from one another. Overall, my findings suggest that Geomorphic Response Units (GRU) are an effective means of identifying patterns in geomorphic structure within Prairie Rivers at both reach and segment scales. Further, I identified links between both Geomorphic Types and GRUs and patterns in abundance of various fish species covering a wide range of life history traits. These findings suggest that GRUs have potential as a valuable fisheries habitat management tool, increasing efficiency of monitoring efforts through quantification of habitat availability, connectivity, and complexity in Prairie River systems.
353

Evaluation of silver nanoparticles impregnated woven fabric microfiltration membranes for potable water treatment

Achisa, Cleophas Mecha 15 July 2014 (has links)
Submitted in fulfilment of the requirements of the Degree of Master of Technology: Chemical Engineering, Durban University of Technology, 2013. / Lack of access to clean and safe potable water, especially for people living in rural areas of developing economies, is a matter of great concern in different parts of the world. Measures taken to address the challenges arising from this problem include the improvement of existing water purification methods and development of new appropriate technologies such as point of use (POU) water treatment technologies. One such appropriate POU technology is the Remote Rural Water Treatment System (RRWTS) developed at Durban University of Technology (DUT) in South Africa. The RRWTS is based on polyester woven fabric microfiltration (WFMF) membranes and other locally sourced materials. The filtration unit consists of flat sheet modules assembled into a pack and permeate outlets connected to a manifold and then to a tap. The system is gravity driven and therefore eliminates the use of pumps and electricity. This system has shown potential for use in water treatment as it produces permeate with turbidity below 1 NTU, has a high permeate flow rate, and is easy to use and maintain. However, the major challenge facing its use is that permeate does not meet the set microbiological standards for drinking water (zero E. coli in 100 mL treated water). The RRWTS can ideally remove 95 to 99 per cent of the influent E. coli. This necessitates the use of a separate disinfection step, often using chlorine for complete removal of microbial contaminants. The objectives of this study were: to investigate the incorporation of silver nanoparticles (AgNPs) into the WFMF membrane; to evaluate the disinfection efficacy of the AgNPs impregnated filter (coated filter); and to determine the long term performance of the coated filter in terms of disinfection and silver elution (90 days). The study was conducted in four stages. Firstly, AgNPs were incorporated on the membrane using in situ chemical reduction of silver nitrate using sodium borohydride. Secondly, the filters were characterized using scanning electron microscopy (SEM) to determine the morphology, and the Sessile drop method for contact angle measurement was employed to determine the membrane hydrophilicity. In addition, X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR) spectroscopy and UV- Visible Spectroscopy iii were used to investigate the presence of AgNPs on the coated filter. Thereafter, the antibacterial efficacy of the filters was evaluated using a laboratory scale experimental rig and different microbial assays. Raw river water and deionized water spiked with E.coli (synthetic feed) were used as feed. Lastly, the effects of concentration of E.coli in the feed and silver elution on the disinfection performance of the coated filter over time were investigated. The performance criteria were based on permeate quality and they included: turbidity, concentration of E.coli, and silver concentration. The characterization results depicted that AgNPs were successfully immobilized on the WFMF membranes by in situ chemical reduction. The incorporation of AgNPs was ascertained using UV-Vis Spectrophotometry, FT-IR and XRD. The Sessile drop test indicated that the membrane became more hydrophilic (77 per cent decrease in water contact angle) and the permeability increased significantly as a result of the coating (p <0.05). The coated filters demonstrated excellent filtration performance producing permeate with turbidity less than 1 NTU for feed turbidities between 40 and 700 NTU. The disinfection efficacy was found to be excellent, producing permeate with zero E.coli concentration for feed concentrations between 10,000 CFU/ 100 mL and 85,000 CFU/100 mL. The E.coli removal efficiency was 100 per cent for a period of 63 days of continuous filtration. The ICP Atomic Emission Spectrometer (ICP-AES) results showed that the leaching of silver from the coated filters over time (90 days) was always below 0.1 mg/L which is the widely accepted guideline for potable water. From the literature surveyed, this is the first study which investigated the use of AgNPs in WFMF membranes for potable water disinfection. The coated filters treated water to the set international standards for potable water in terms of physical and microbiological quality. However, the study did not comprise investigation into the effect of different silver loadings on the filter performance. The study also employed E.coli as the indicator organism for faecal contamination. The results obtained can be used as a model for future work using other microorganisms and different silver loadings in order to compare the performance.
354

A prospective comparative study of continuous and intermittent endotracheal tube cuff pressure measurement in an adult intensive care unit

Memela, Mduduzi Emmanuel January 2010 (has links)
Submitted in fulfilment of the Master's Degree in Clinical Technology, Durban University of Technology, 2010. / Introduction: The aim of this study was to establish the most reliable standard method for monitoring endotracheal tube cuff pressure in an intensive care unit. Methodology: The study was conducted at King Edward VIII Hospital ICU on adult patients undergoing prolonged intubation of more than 24 hours. Consent was obtained from the patient’s next of kin. The patient’s Pcuff for this study was recorded in two ways simultaneously for a period of 12 hours during the day. The principal investigator recorded the Pcuff thrice during the study period using the Posey cufflator®. Continuous recording was done using a pressure transducer connected to the Nihon Kohden BSM®. Factors causing changes in Pcuff were also documented. Results: Thirty-five critically ill adult patients were enrolled into the study. Nineteen (54.3%) of the subjects were male. Seventeen out of 35 subjects were studied for the entire 720 minute period. The mean time of study of the group was 667 minutes with the lowest period being 135 minutes for one patient. The group mean ± Standard deviation (SD) was 26.6 8.7 with a 95% confidence index of 9.2 – 44.0 and the median value was 25 for continuous readings. For the entire group, 13% of the time was spent in the low pressure range (< 20 cmH2O), while 23% was spent in the high pressure (> 30 cmH2O). A mean of 64% of the time was spent in the normal pressure range. Overall, the most frequently encountered events that caused pressure changes were body movement, coughing, head movement and suctioning accounting for 26.2%, 20.1%, 19.2% and 9.4% respectively. For intermittent readings, the mean ± SD of all patients for T0 was 25.3 ± 6.9; for T6 25.9 ± 8.7 and for T12 24.8 ± 3.8. The overall mean ± SD for all readings was 25.6 ± 7.1. For the entire group, 12% of the time was spent in the low pressure range (< 20 cmH2O), while 5% was spent in the high pressure (> 30 cmH2O). A mean of 83% of the time was spent in the normal pressure range. The correlation between intermittent pressure and the continuous reading at the same time was r = 0.87. iii Discussion: Continuous monitoring of Pcuff indicated that the endotracheal cuff pressure varies extensively during mechanical ventilation in critically ill patients, such variation being noted both between patients and within an individual patient. In an attempt to compare intermittent and continuous monitoring of endotracheal cuff pressures, a good correlation between the two measurements was demonstrated. However, the variations in pressures noted for an individual patient would not have been detected if endotracheal cuff pressures were monitored intermittently. Hence, with continuous monitoring the pressure changes may be detected early. Conclusion: Continuous monitoring of cuff pressure during mechanical ventilation in intensive care units is thus recommended for all patients. If intermittent monitoring is performed, it should be more frequently than eight-hourly. It is recommended that a pressure range of 20-30 cmH2O still be used as the normal range. The role of self adjusting pressure devices, although needing further exploration, holds much promise. / DUT Postgraduate Development Services.
355

Mobil Radiologi : Radiologins Roll i Samhället

Axbåge, Daniel, Werner, Johanna January 2016 (has links)
No description available.
356

Pattern recognition systems design on parallel GPU architectures for breast lesions characterisation employing multimodality images

Sidiropoulos, Konstantinos January 2014 (has links)
The aim of this research was to address the computational complexity in designing multimodality Computer-Aided Diagnosis (CAD) systems for characterising breast lesions, by harnessing the general purpose computational potential of consumer-level Graphics Processing Units (GPUs) through parallel programming methods. The complexity in designing such systems lies on the increased dimensionality of the problem, due to the multiple imaging modalities involved, on the inherent complexity of optimal design methods for securing high precision, and on assessing the performance of the design prior to deployment in a clinical environment, employing unbiased system evaluation methods. For the purposes of this research, a Pattern Recognition (PR)-system was designed to provide highest possible precision by programming in parallel the multiprocessors of the NVIDIA’s GPU-cards, GeForce 8800GT or 580GTX, and using the CUDA programming framework and C++. The PR-system was built around the Probabilistic Neural Network classifier and its performance was evaluated by a re-substitution method, for estimating the system’s highest accuracy, and by the external cross validation method, for assessing the PR-system’s unbiased accuracy to new, “unseen” by the system, data. Data comprised images of patients with histologically verified (benign or malignant) breast lesions, who underwent both ultrasound (US) and digital mammography (DM). Lesions were outlined on the images by an experienced radiologist, and textural features were calculated. Regarding breast lesion classification, the accuracies for discriminating malignant from benign lesions were, 85.5% using US-features alone, 82.3% employing DM-features alone, and 93.5% combining US and DM features. Mean accuracy to new “unseen” data for the combined US and DM features was 81%. Those classification accuracies were about 10% higher than accuracies achieved on a single CPU, using sequential programming methods, and 150-fold faster. In addition, benign lesions were found smoother, more homogeneous, and containing larger structures. Additionally, the PR-system design was adapted for tackling other medical problems, as a proof of its generalisation. These included classification of rare brain tumours, (achieving 78.6% for overall accuracy (OA) and 73.8% for estimated generalisation accuracy (GA), and accelerating system design 267 times), discrimination of patients with micro-ischemic and multiple sclerosis lesions (90.2% OA and 80% GA with 32-fold design acceleration), classification of normal and pathological knee cartilages (93.2% OA and 89% GA with 257-fold design acceleration), and separation of low from high grade laryngeal cancer cases (93.2% OA and 89% GA, with 130-fold design acceleration). The proposed PR-system improves breast-lesion discrimination accuracy, it may be redesigned on site when new verified data are incorporated in its depository, and it may serve as a second opinion tool in a clinical environment.
357

Development of GPU-based incompressible SPH and application to sloshing problems in the oil industry

Dickenson, Paul January 2014 (has links)
No description available.
358

Specialistsjuksköterskors upplevelser av att vårda barn i livets slutskede inom barnintensivvård

Eliasson, Carina, Loderini, Daniela January 2015 (has links)
Bakgrund: Specialistsjuksköterskans uppgifter på en barnintensivvårdsavdelning (BIVA) är att vårda barn och det innefattar även att vårda barn i livets slutskede. Av de barn som vårdas på en barnintensivavdelning avlider cirka två procent. Att vårda barn och familjen i en situation där fortsatt vård och överlevnad för barnet är utsiktslöst är en tung och ansvarsfull uppgift. Syfte: Studiens syfte var att belysa specialistsjuksköterskors upplevelser av att ha vårdat ett barn vid livets slutskede på en BIVA. Metod: Som datasamlingsmetod användes semistrukturerade intervjuer med sju specialistutbildade sjuksköterskor. Intervjuerna genomfördes med hjälp av en intervjuguide bestående av en huvudfråga och därefter följdfrågor. Data bearbetades utifrån kvalitativ innehållsanalys med en beskrivande ansats. Resultat: Resultatet presenteras i tre kategorier och tio subkategorier. De tre kategorierna var följande: Att känna sig trygg och erfaren i att vårda ett döende barn, familjen i fokus samt upplevelsen av stöd och strategier i det komplexa vårdandet. Diskussion: Trots att upplevelsen av att vårda barn i livets slut är en tung och känslomässig uppgift ansåg samtliga informanter det som en ansvarsfull och positiv uppgift där de kunde göra föräldrarnas sista stund med sina barn till ett fint och ljust minne. / One of the caring tasks that specialist nurses, working in the (PICU) perform, and have to face in the daily profession is to care for children who are facing the end of life in Sweden. Approximately two percent of all the children being cared for in the PICU dies. To care for children and their families when further treatment is futile is a heavy surrounding life and death. The goal of this study was to investigate the experiences of specialist nurses caring for children at the end of life. Qualitative content analyze were used as a method. Seven semi-structured interviews, with a descriptive approach, were transcribed to condensed meanings. Finally, the meaning was coded into ten subcategories within three main categories. Conclusion of this study indicated that pediatric intensive care nurses indicated their work heavy emotionally. The nurses play a vital role to the family´s final time whit their children. It is in the hands of the nurses to support and make the final time as valuable and beautiful as possible for the family.
359

Test Bench for Experimental Research and Identification of Electrohydraulic Steering Units

Angelov, Ilcho, Mitov, Alexander 03 May 2016 (has links) (PDF)
The paper presents design solution and physical implementation of a system for examination of electro hydraulic steering based on OSPE 200 components. The implementation is based on synthesis of required hydraulic and structure parameters, presented in a previous paper. Now we present the interconnection of the digital control system and the closed-loop flow diagram. A formal description of embedded software is presented too, which supports operation of PI control algorithm in real-time. Identification is performed based on experimentally reported the transitional process by developing mathematical models. Presents the structure and capabilities of the models for identification, as well as procedures for their validation.
360

B-2 Flight Test Implementation of an Ethernet Based Network System for Data Acquisition

Hochner, William "Bill" 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / Northrop Grumman Corporation's B-2 Flight Test Instrumentation team is revamping its entire Data Acquisition System (DAS) to be an Ethernet based network (EBN) system that will provide simplified wiring, higher speeds, greater capacity, and control over the data. The old system became obsolete in terms of capability and maintainability. New on-board avionic systems also demand that the Flight Test Instrumentation group (INSTR) accommodate fiber and high speed Ethernet data. In addition, the footprint and location for INSTR systems and components will be moved to remote areas. INSTR engineering selected the Teletronics Technology Corporation's Ethernet networked Data Acquisition Units (DAUs), known as MnDAUs, as the core system. Prior to the first flight utilization of the new INSTR DAS will undergo extensive lab and field testing to assure flight test effectiveness and the accuracy of all necessary data products. The goal is to acquire and employ the best system available while avoiding costly lessons.

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