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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.
41

The experiences of parents where pregnancy ended in an unplanned caeserean section

Ceronio, Caroline Celia 11 February 2014 (has links)
M.Cur. (Midwifery and Neonatal Nursing) / The purpose of this study is to determine the experiences of parents prior to, during and following an unplanned caesarean section. Parents who experience this event have mixed emotions. The related occurrences may influence their behaviour and consequently their relationships with their spouses, themselves and their environment. These interact with each other continually and thus need to be looked at in context. The "Nursing of the Whole Person Theory' ensures a wholistic approach to the parents. Unstructured, in-depth interviews held with five mothers and five fathers, respectively, on day three post-delivery, were transcribed and analyzed. At six weeks a follow-up semistructured questionnaire was answered by these same respondents and analyzed. The experiences of the parents were then compared. A literature control was undertaken in order to determine what the conclusions of other researchers in this field are. The results of the literature search were compared to that of the present study and conclusions reached. Recommendations concerning nursing practice, education and further study were made at the end of the study, including a listing of the limitations affecting the study.
42

Measurement of absolute Drell-Yan cross-sections using a 190-GeV π⁻ beam at the COMPASS-II experiment / Mesure de sections efficaces absolues Drell-Yan à l'aide d'un faisceau de π⁻ de 190-GeV à COMPASS

Meyer-Conde, Marco 21 November 2019 (has links)
La prise de données réalisée en 2015 par la collaboration COMPASS au CERN a permis de collecter un nombre significatif de paires de muons de grande masse. Ces dernières proviennent de l’interaction d’un faisceau de pions négatifs d’impulsion 190 GeV/c sur des cibles d’ammoniac (NH₃), d’aluminium (Al) ou de tungstène (W). Ce travail de thèse décrit les différentes étapes d’analyse des données de Drell-Yan dans la région de masse entre 4.3 et 8.5 GeV/c², depuis la reconstruction des traces du pion incident et des muons diffusés, jusqu’à l'extraction des sections efficaces finales. Ces étapes comprennent la détermination du flux incident et des densités des trois cibles, l’évaluation des différentes efficacités expérimentales, le calcul de l’acceptance de l’appareillage par simulation Monte-Carlo et la réduction des données à des paires de muons. Présentées en fonction de la variable de Feynman xF et de l’impulsion transverse pT, les sections efficaces Drell-Yan sont comparées aux calculs théoriques aux ordres NLO et NNLO, ainsi qu’aux résultats des expériences antérieures. Une interprétation plus poussée des résultats donnera accès aux distributions des partons dans le pion et à l’étude des effets de la matière froide dans les noyaux. / The COMPASS collaboration at CERN collected a significant amount of Drell-Yan data in 2015. The measured lepton pairs originate from the interaction of a negatively charged pion beam at 190 GeV/c with ammonia targets (NH₃), aluminum (Al) or tungsten (W). The analysis step using the Drell-Yan data are discussed in the mass range between 4.3 and 8.5 GeV/c², starting from the reconstruction of the incoming pion beam and the scattered muons, until the extraction of the Drell-Yan cross-sections. These steps include the determination of the incoming beam flux and the three target densities, the overall efficiency of the experimental apparatus, the acceptance of this spectrometer using Monte-Carlo simulations, and the reduction of the initial data to muon pairs. The Drell-Yan cross-sections, expressed in terms of the scaling variable xF and the transverse momentum pT, are compared with theoretical predictions at NLO and NNLO, as well as some previously published results. An advanced interpretation of these results would give access to the partonic distribution of the pion and lead to the study of cold nuclear matter effects.
43

Mesure du flux et de la section efficace des antineutrinos dans le détecteur proche de l'expérience T2K / Measurement of the antineutrino flux and cross section at the near detector of the T2K experiment

Riccio, Ciro 15 January 2018 (has links)
T2K (Tokai to Kamioka) est une expérience d’oscillation de neutrinos muoniques sur une longue ligne de base, située au Japon. Elle est conçue pour mesurer le changement de saveur des neutrinos d’un faisceau produit à l’aide d’un accélérateur au laboratoire JPARC de Tokai. Les détecteurs proche et lointain sont placés légèrement hors axe par rapport au faisceau. Depuis la découverte en 2013 de l’apparition de neutrinos électroniques, T2K a inversé la polarité des cornes magnétiques intervenant dans la production du faisceau, afin de produire un faisceau d’antineutrinos et d’augmenter la sensibilité de l’expérience à la violation de la charge-parité dans le secteur leptonique. Le faisceau produit est alors dominé par les antineutrinos muoniques avec une composante mesurable de neutrinos muoniques. L’analyse simultanée, dans les données prises avec le faisceau de neutrinos et le faisceau d’antineutrinos, des interactions par courant chargé dans le détecteur proche ND280, permet de réduire l’impact sur les analyses d’oscillation des incertitudes liées au flux de (anti)neutrinos et à leur section efficace d’interaction. Les données de ND280 permettent également de mesurer les sections efficaces d’interaction des antineutrinos d’énergie proche de 600 MeV. La bonne connaissance du processus d’interaction des (anti)neutrinos avec les noyaux atomiques est cruciale pour interpréter les résultats de l’expérience en termes d’oscillations. De nombreux modèles théoriques ont été développés pour décrire les effets nucléaires lors des interactions des (anti)neutrinos, mais une vison globale cohérente n’a pas encore émergé. En particulier, des mesures variées de section efficace d’interaction par courant chargé sans production de pion dans l’état final suggèrent la possibilité pour les neutrinos d’interagir avec des paires de nucléons corrélés, entrainant l’éjection de plus d’un nucleon hors du noyau (composante dite “multi-nucléon”). Divers modèles ont proposé des estimations différentes de ce processus et une mesure précise et sans ambiguité n’est pas encore disponible. Ce travail de thèse se concentre sur trois études. La première détaille la sélection des interactions de neutrinos muoniques par courant chargé dans le détecteur proche hors axe. Dans un premier temps l’échantillon de données était divisé en deux selon le nombre de traces chargées de l’événement, puis l’accumulation de davantage de données a permis la séparation de l’échantillon en trois lots selon le contenu en pions de l’événement. La seconde étude consiste en la mesure simultanée de la section efficace d’interaction des neutrinos et des antineutrinos muoniques par courant chargé, conduisant à un état final sans pion mesuré dans le détecteur ND280. Ces sections efficaces sont extraites en fonction de l’impulsion et de l’angle du muon issu de l’interaction, permettant ainsi d’évaluer la somme, la différence et l’asymétrie entre les sections efficaces des neutrinos et des antineutrinos. La somme permet d’isoler la composante d’interférence vecteur-axial de la section efficace, et la différence est sensible à la composante multi-nucléons. L’asymétrie permet d’estimer directement le biais éventuel sur la mesure de la phase de violation de CP dû à la modélisation des sections efficaces, dans l’analyse d’oscillation de neutrinos. La dernière partie de la thèse étudie la proposition d’utiliser la technologie dite de multi-PMT pour le detector Hyper-Kamiokande, version à plus grande échelle de Super-Kamiokande, ainsi que la possibilité d’étudier le flux de neutrinos avec un détecteur basé sur le rayonnement Cherenkov dans l’eau, et placé à environ 2 km de l’origine du faisceau de neutrinos. Un multi-PMT est une sphère de plastique contenant 26 tubes photomultiplicateurs, qui pourrait améliorer l’efficacité des futurs détecteurs basés sur le rayonnement Cherenkov dans l’eau. / T2K (Tokai to Kamioka) is a long-baseline neutrino oscillation experiment installed in Japan and designed to measure neutrino flavor oscillation using an off-axis neutrino beam produced at the J-PARC accelerator facility in Tokai. Since its discovery of electron neutrino appearance in 2013, T2K has switched its beam magnet polarities to run in antineutrino beam mode in order to enhance its sensitivity to the charge-parity violation in the leptonic sector. The beam is dominated by muon antineutrinos, but it also contains a sizable contamination from muon neutrinos. The analysis of both neutrino and antineutrino charged-current interactions in the off-axis near detector ND280, provides a significant reduction of the flux prediction and cross-section modeling systematic uncertainties in the oscillation analysis. ND280 data also gives us the opportunity to measure antineutrinos cross-sections at the energy around 600 MeV. Information on (anti)neutrino scattering is vital for the interpretation of neutrino oscillation. Many theoretical models have been developed to describe the nuclear effects in (anti)neutrino scattering, but a consistent picture has yet to emerge. In particular, various measurements of charged-current cross-section without production of pions in the final state have suggested the presence of another channel where neutrinos interact with pairs of correlated nucleons and more than one nucleon is knocked-out from the nucleus (multi-nucleon component). Various models have proposed different estimations of such process and a precise and unambiguous measurement is not yet available. This thesis work is focused on three different arguments. First the selections of CC interactions of muon neutrinos in antineutrino beam in the off-axis near detector. In a first iteration this sample has been divided into two sub-sample based on the track multiplicity, then with more statistic a separation into three sub-samples based on the pion content in each event was possible. Then on the simultaneous measurement of the double-differential muon neutrino and antineutrino charged-current cross-section without pions in the final state using the off-axis near detector. The neutrino and antineutrino cross-sections will be simultaneously extracted as a function of muon momentum and angle with a likelihood fit, including proper estimation of the correlations, allowing the evaluation of the sum, difference and asymmetry between the two cross-sections. The sum isolates the axial-vector interference term of the cross-section, and the difference enhances the sensitivity to the multinucleon component. The asymmetry is a direct estimation on any possible bias due to mismodeling of (anti)neutrino interactions on the measurement of the CP violation phase in neutrino oscillation. The last topic concerns the proposal of the multi-PMT technology as detector for Hyper-Kamiokande, the upgrade of Super-Kamiokande, and the intermediate water v Cherenkov proposed to study the neutrino flux at ~2 $km$ from the beam production point. A multi-PMT is a plastic sphere filled with 26 photomultiplier tube that could improve the efficiency of the Cherenkov detectors foreseen in the future.
44

A retrospective audit of pain assessment and management post caesarean section at New Somerset Hospital in Cape Town, South Africa

Munsaka, Effraim Frackson 04 April 2023 (has links) (PDF)
Background: The most common major surgical procedure performed worldwide is the caesarean section (CS). Effective pain management is a priority for women undergoing this procedure, to reduce the incidence of persistent pain, (a risk factor for postpartum depression), as well as optimize maternal-neonatal bonding and the successful establishment of breastfeeding. Multimodal analgesia is the gold standard for post-caesarean section analgesia. At present, no perioperative pain management protocols could be identified for the management of patients presenting for CS at regional hospitals in South Africa. This audit aimed to review the folders of patients who underwent CS, with reference to perioperative pain management guidelines for CS. Methods: A descriptive, retrospective, cross-sectional audit was conducted. Three hundred folders (10% of the annual number of caesarean procedures performed) from New Somerset Hospital, a regional hospital in Cape Town, South Africa were reviewed. Results: The women were a mean age of 30 years (SD 6.2). Median gravidity was 3 (IQR 2-3) and parity was 1 (IQR 1-2); 52% had previously undergone a CS. In 93.3%, spinal anaesthesia was employed for CS. Pain assessment was poor, with only 55 (18%) patients having their pain assessed on the day of the operation. Analgesia was prescribed in over 98% of the patients, however, medication was only administered as prescribed in 32.6%. Non-steroidal anti inflammatory drugs (NSAIDs) were prescribed in < 1.67% of cases. None of the patients received a patient-controlled analgesia (PCA), transversus abdominis plane (TAP) block, or wound infusion catheter as supplementary strategies. Conclusions: Pain management for post-CS patient at this hospital is lacking. There is the need for the implementation of a structured assessment tool to improve administration of analgesics in these patients. In addition, the reasons for the omission of NSAIDs from the analgesia regimen requires investigation. Hospitals require post-CS pain protocols to guide management especially in resource-limited settings.
45

Experience of elapsed duration music listening and its relevance to the golden section debate

Phillips, Michelle Elizabeth January 2014 (has links)
No description available.
46

Nutritional and endocrine manipulation of development and thermoregulation in the newborn lamb

Heasman, Lindsay January 1999 (has links)
No description available.
47

Methods for the calculation of cross-sections of interest to nuclear reactor design

Street, A. M. January 1987 (has links)
No description available.
48

A Calculation of the Kaon-Neutron Scattering Cross Section

Hooper, Robert Gibson 06 1900 (has links)
The purpose of this investigation was to study the scattering processes of K+ mesons with neutrons. In order to do such a study one must first make certain basic assumptions about the type of interaction involved and then proceed to calculate physically meaningful qualities which describe the processes. Thus, the problem is this: assuming the validity of Feynman's rules for these strongly interacting particles, calculate the differential and total scattering cross sections for the interaction of scalar K+ mesons and neutrons.
49

A measurement of Z(vv̄)[photon] cross section and limits on anomalous triple gauge couplings at [square root of]s = 7 TeV using CMS

Shrestha, Shruti January 1900 (has links)
Doctor of Philosophy / Department of Physics / Yurii Maravin / In this thesis, the first measurement of Z(vv̄)[photon] cross section in pp collisions at [square root of]s = 7 TeV has been done using data collected by the CMS detector. The measured cross section is 21.3 ± 4.2 (stat.) ± 4.3 (syst.) ± 0.5 (lumi.) fb. This measurement is based on the observations of events with missing transverse energy in excess of 130 GeV and photon in the rapidity range [eta] < 1.44 of transverse momentum in excess of 145 GeV in a data sample corresponding to an integrated luminosity of 5 fb⁻¹. This measured cross section is in good agreement with the theoretical prediction of 21.9 ± 1.1 fb from BAUR. Further, neutral triple gauge couplings involving Z bosons and photons have been studied. No evidence for the presence of such couplings is observed and is in agreement with the predictions of the standard model. We set the most stringent limits to date on these triple gauge couplings.
50

Caesarean section deliveried in public sector hospitals in South Africa, 2001-2009.

Monticelli, Fiorenza 05 April 2013 (has links)
Introduction There is concern that C-section rates are increasing in the public health sector in South Africa and wide variation has been reported between districts, provinces and hospitals. This study is a comprehensive analysis of C-section rates in all public sector hospitals during 2000/01- 2008/09 by facility, district and province. It aims to inform decision makers in maternal health services of the trends and patterns occurring in C-section rates in South African public sector hospitals. Variation in C-section rates is described to highlight the differences in care that pregnant women receive in different parts of the country and to illustrate where inequity of resource allocation is occurring, as well as highlighting possible data quality problems. Methodology This is a descriptive study using quantitative methods of analysis on secondary data obtained from the National Department of Health’s routinely collected data specific to Caesarean sections in the DHIS. C-section averages are weighted by taking the number of deliveries per facility and level into consideration. Results 1. Wide variation is noted between individual facilities, between and within provinces and districts and within the different levels of hospitals in 2008/09. The mean weighted C-section rate ranges from 17.2% in District Hospitals to 40.7% in Specialised Maternity Hospitals. A 3.7 fold difference between the highest and lowest district average C-section rates is seen for District Hospitals. Within provinces, average District Hospital C-section rates vary by as much as 3.5 fold between districts. Interdistrict variation in Regional Hospitals shows a 3.3 fold difference between the lowest and highest average district rates. Among the eight National Central Hospitals there is a 2.5 fold difference between the highest (79.7%) and lowest (31.7%) facility C-section rates. Nationally a total of 23 District Hospitals had C-section rates below 5% and nine hospitals of varying levels had rates of over 50% 2. Caesarean Section rate trends, 2000/01 – 2008/09 are increasing. Nationally the average C-section rate in South Africa increased by 6.3 percentage points from 18.1% in 2000/01 to 24.4% in 2008/09, with an average annual compounded growth rate of 3.8%. Bivariate linear regression analysis confirms there is a positive linear relationship between time (year) and C-section rate (p<0.001). All levels of hospitals showed an increasing trend over the nine years, (p<0.001), with the rate in Provincial Hospitals having increased by the highest amount (1.40%) year on year and District Hospitals, the least (0.48%). Trends within certain districts and individual hospitals however, show a decline. 3. A strong relationship between level of deprivation and C-section rate exists when adjusting data for provincial variation Bivariate linear regression analysis revealed no association between the level of deprivation of the population at district level and the mean C-sections rate per district (p=0.130). Multiple regression analysis adjusted for the effect of province, reveals a significant association (p=0.044). A negative association between the DI (p=0.006) and Csection rate is seen in eight out of nine provinces. 4. Data quality of C-sections and deliveries in the DHIS needs improving Data quality in the DHIS leaves uncertainty in some instances whether C-section rate trends are a true reflection or not. The C-section rate indicator on its own is unable to inform on the full spectrum of emergency obstetric care. The definition of C-section rate for primary health care currently only considers deliveries in District Hospitals. The national C-section rate for primary health care in the country however, reduces from 17.2% to 13.2% when including the deliveries which take place in CHCs. Conclusions The quality of data relating to C-sections (number of births, C-sections and hospital categorisation) in the DHIS needs to be improved in order to enable accurate monitoring and should include deliveries and C-sections which take place in Community Health Centres to allow for a more accurate reflection of C-section rate in primary health care. The C-section rate indicator on its own is insufficient to adequately inform on the full spectrum and quality of the provision of emergency obstetric care in South Africa. Including additional indicators to the DHIS, such as the UN process indicators, could improve on the current knowledge and monitoring of the provision of emergency obstetric care in South Africa. The wide variation in C-section rates seen among District Hospitals and the C-section rates between and within districts and provinces, suggest inequity in resource allocation and irregular service delivery patterns. Reasons and solutions for these wide differences need to be found, which are likely to be unique to each district and province. Further studies are needed to investigate the access of poorer women, especially those in remote rural areas to emergency obstetric care services.

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