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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.
291

Caractérisation des variabilités temporelle et spatiale de la pollution en Île-de-France : De la mesure de l'exposition individuelle à la définition des sources / Characterization of the temporal and spatial variabilities of pollution in Île-de-France : From personal exposure measurements to sources definition

Languille, Baptiste 02 December 2019 (has links)
La pollution atmosphérique résulte d’un mélange complexe de composés, des gaz et des particules, dont les effets sont notoirement néfastes. Les composés organiques volatils (COV) tiennent un rôle prépondérant dans la chimie atmosphérique et sont précurseurs d’ozone et d’aérosols organiques secondaires (AOS). En Île-de-France, l’exposition à la pollution est préoccupante ; or, des incertitudes significatives sont toujours associées aux sources de polluants, ainsi qu’à leur intensité et leurs variabilités à différentes échelles de temps et très peu d’investigations ont porté sur la quantification de l’exposition individuelle. Dans ce contexte, cette thèse a cherché à mieux caractériser les variabilités temporelle et spatiale de la pollution en Île-de-France.La fiabilité discutable des capteurs portables a été dépassée par l’élaboration d’un protocole de sélection et de qualification comprenant différents tests en mesures fixes, en chambre et en mobilité. Cette nouvelle méthodologie, basée notamment sur l’utilisation d’un outil combinant différents indicateurs statistiques, a été appliquée pour retenir l’AE51, le Cairclip et le Canarin, mesurant respectivement le carbone suie (BC), le dioxyde d’azote (NO2) et les particules (PM).Ces trois capteurs ont été déployés au cours de campagnes de mesures impliquant une trentaine de volontaires. L’exposition individuelle ainsi quantifiée est plus élevée à l’automne qu’au printemps et varie de manière substantielle en fonction des différents environnements fréquentés. La proximité de la circulation routière (pour le BC et le NO2) ainsi que les activités de cuisine et la fumée de tabac (pour les PM) présentent des contributions importantes à l’exposition totale (jusqu’à 34 %, 26 % et 44 % respectivement), alors même que le temps passé dans ces environnements est faible.En plus du trafic routier, le BC est traditionnellement imputé au feu de bois. Une campagne hivernale de mesures (3,5 mois) a permis d’imputer respectivement 22 % et 47 % des COV mesurés à ces deux sources. Certains composés ont été mesurés et associés au feu de bois pour la première fois en air ambiant comme le benzènediol et le méthylbutènone. Une comparaison avec l’inventaire régional des émissions a permis d’identifier des similitudes et des différences pour proposer des améliorations. / Air pollution results from a complex mixture of compounds, gases and particulate matter, whose effects have proven to be harmful. Volatile organic compounds (VOCs) play a major role in atmospheric chemistry and are precursors of ozone and secondary organic aerosols (SOAs). In Île-de-France, exposure to pollution is a concern; however, significant uncertainties are still associated with the pollutants’ sources, as well as their intensity and variability at different time scales, and very few investigations have focused on quantifying personal exposure. In this context, this research sought to better characterize the temporal and spatial variabilities of pollution in Île-de-France.The questionable reliability of portable sensors has been addressed by the design of a selection and qualification protocol including various tests in static measurements, controlled chamber and mobility. This new methodology, based in particular on the use of a tool combining different statistical indicators, was applied to choose the AE51, Cairclip and Canarin, measuring black carbon (BC), nitrogen dioxide (NO2) and particulate matter (PM) respectively.These three sensors were deployed during measurement campaigns involving about thirty volunteers. The personal exposure thus quantified is higher in fall than in spring and varies substantially according to the different environments frequented. Proximity to road traffic (for BC and NO2) as well as cooking activities and tobacco smoke (for PM) make significant contributions to total exposure (up to 34 %, 26 % and 44 % respectively), even though the time spent in these environments is short.In addition to road traffic, BC is traditionally attributed to wood burning. A winter measurement campaign (3.5 months) attributed respectively 22 % and 47 % of the measured VOCs to these two sources. Compounds including benzenediol and methylbuteone were measured and associated with wood burning for the first time in ambient air. A comparison with the regional emissions inventory identified similarities as well as differences and suggested improvements.
292

Características materno perinatales de gestantes COVID-19 en un hospital nacional de Lima, Perú / Maternal and perinatal characteristics of pregnant women with COVID-19 in a national hospital in Lima, Per

HUERTA, IGOR, ELIAS ESTRADA, JOSE CARLOS, Coronado, Julia 06 1900 (has links)
Introducción. La pandemia por coronavirus 2019 (COVID-19) se ha extendido en más de 100 países. La información específica sobre su comportamiento en el embarazo y parto sigue siendo limitada. Objetivo. Describir las características materno perinatales de pacientes gestantes con COVID-19 en un hospital terciario. Métodos. Estudio descriptivo. Se seleccionó todas las gestantes hospitalizadas por el servicio de emergencia de gineco-obstetricia entre el 24 de marzo y el 07 de mayo del 2020 y que tuvieron diagnóstico de infección por SARS-CoV-2, mediante la prueba rápida o la prueba RT-PCR. Se revisó la historia clínica y registros hospitalarios buscando variables sociodemográficas, antecedentes, manifestaciones clínicas, serología materna, complicaciones obstétricas, vía de parto y aspectos perinatales. Resultados. Se encontró 41 casos de pacientes con diagnóstico de SARS-CoV-2. Un 9,2% tuvo resultado de prueba rápida positiva, Los síntomas más comunes fueron tos en 84,6%, fiebre en 76,9% y dolor de garganta en 61,5%. Un 68.2% estuvo asintomática, 19,5% tuvo enfermedad leve y 7,3% moderada. Dos casos de neumonía severa requirieron ventilación no invasiva. No se registró muerte materna. 21,7% de los partos fue vía vaginal y 78,3% por cesárea. Hubo un caso de neonato por parto vaginal con PCR positivo al octavo día de vida. Conclusiones. Hubo un alto porcentaje de pacientes gestantes PCR positivas asintomáticas. Es necesario implementar el tamizaje universal en parturientas en el protocolo de flujo de gestantes en cada institución. / Introduction: The pandemic of coronavirus disease 2019 (COVID-19) has spread to more than 100 countries. Specific information about its behavior in pregnancy is still limited. Objective: To describe the maternal and perinatal characteristics of pregnant patients infected with COVID-19 and their newborns in a tertiary referral hospital. Methods: Descriptive study. Subjects were all pregnant patients admitted to the OB/ GYN Emergency Department of the Edgardo Rebagliati Martins National Hospital from March 24 to May 7, 2020, who were diagnosed with SARS-CoV-2 infection by rapid test or by RT-PCR test. Medical and hospital records were reviewed to retrieve sociodemographic data, patient’s history, clinical manifestations, maternal serology, obstetric complications, delivery mode and perinatal aspects. Results: 41 patients diagnosed with SARS-CoV-2 were identified. 9.2% of all admissions had a positive rapid test. The most common symptoms were cough in 84.6%, fever in 76.9% and sore throat in 61.5%. 68.2% of the patients were asymptomatic, 19.5% had mild illness and 7.3 %, moderate. 2 cases progressed to severe pneumonia requiring non-invasive ventilation. No maternal deaths were recorded. 21.7% were vaginal deliveries, while 78.3% were C-sections. One baby born in a vaginal delivery had a positive PCR result on day 8. Conclusions: A large percentage of asymptomatic pregnant patients had a positive PCR test. Implementing universal screening among patients in l flow protocol is necessary for all institutions.
293

Colitis amebiana fulminante con desenlace fatal en un paciente con probable infección por SARS-CoV- 2 / Fulminant amebic colitis with fatal outcome in a patient with probable SARS-COV-2 infection

Somocurcio, José, Ayquipa, Tula, PINEDA, VANESSA 11 October 2021 (has links)
Se reporta el caso de un varón de 62 años quien presentó tos y dolor abdominal por dos semanas, con hallazgos tomográficos pulmonares compatibles con probable infección por SARS-CoV-2, que recibió tempranamente corticoterapia a dosis altas y de manera ambulatoria. El paciente presentó evolución tórpida, fue hospitalizado y falleció en el posoperatorio inmediato por un cuadro de abdomen agudo quirúrgico. El estudio anatomopatológico mostró estructuras parasitarias con características compatibles con amebas, como causa de una colitis aguda fulminante complicada, con perforación múltiple y peritonitis aguda. La colitis aguda fulminante por amebiasis intestinal en el contexto de un paciente con probable COVID-19 no había sido reportada en el Perú. Resulta importante resaltar la presentación fulminante con desenlace fatal de esta infección parasitaria prevalente en nuestro medio, en el contexto del uso de corticoides ante una probable infección pulmonar por COVID-19. / We report the case of a 62-year-old male with cough and abdominal pain for two weeks, associated with pulmonary tomographic findings compatible with probable infection by SARS-CoV-2, and who received high doses of early corticotherapy as an outpatient. The patient showed clinical deterioration, was hospitalized and died in the immediate postoperative period due to acute surgical abdomen. The anatomopathological study showed parasitic structures with characteristics compatible with amebae, which was pointed to as the cause of a complicated acute fulminant colitis, with multiple perforations and acute peritonitis. Acute fulminant colitis due to intestinal amebiasis in the context of a patient with probable COVID-19 had not been previously reported in Peru. It is important to highlight the fulminant presentation with fatal outcome of this prevalent parasitic infection, in the context of corticosteroids use in a probable SARS-CoV-2 pulmonary infection.
294

Det vi vet om ursprunget och evolutionen av SARS-CoV-2 : - Implementering av aktuella händelser i gymnasieskolan / What we know about the origin and the evolution of SARS-CoV-2 : - Implementation of contemporary events in upper secondary school

Unelind, Malin January 2021 (has links)
SARS-CoV-2 började cirkulera i slutet av 2019 och ungefär tre månader senare klassades utbrottet som en pandemi. Idag, ungefär ett och ett halvt år efter virusutbrottet kämpar människor i hela världen fortfarande för att ta sig ur kriserna som pandemin orsakar. Trots stora forskningsinsatser är det ännu mycket som är ovisst kring virusets uppkomst. Olika teorier försöker bevisas men till dagens datum är det inte bekräftat var SARS-CoV-2 har sitt ursprung. Det verkar troligt att SARS-CoV-2 har en gemensam förfader med β-coronaviruset RaTG13. Det är sannolikt att fladdermus tillsammans med minst en mellanvärd har varit inblandad i uppkomsten av viruset. Viruset har gett upphov till flera varianter som spridit ut sig i världen. Globalt samarbete med övervakning av mutationer och varianter är viktigt för hur utvecklingen av pandemin ska fortgå. Med SARS-CoV-2 och Covid-19-pandemin som utgångspunkt analyseras möjligheter och utmaningar med undervisning i gymnasieskolan om aktuella stora händelser. / The outbreak of SARS-CoV-2 occurred at the end of 2019 and three months later, it was declared as a pandemic. Today, roughly one and a half years later, people across the world are still struggling to get out of the crises caused by the pandemic. Despite the huge efforts within science, much is still uncertain about the virus’ origin. Different theories are trying to be proven by scientists but to date, there is no confirmation from where the virus has its origin, nor whether one or several intermediate hosts have been involved. It seems likely that SARS- CoV-2 has a common ancestor with the bat β-coronavirus RaTG13. Therefore, it is probable that bats with at least one other intermediate host have been involved in the origin of the virus. Several variants have emerged and spread throughout the world. Global cooperation in regards of surveilling mutations and variants is of great importance regarding the development of the pandemic. Using SARS-CoV-2 and the Covid-19 pandemic as a focal point, there is an analysis showing opportunities and challenges when teaching big contemporary events.
295

Self-medication practices during the COVID-19 pandemic among the adult population in Peru: A cross-sectional survey

Quispe-Cañari, Jean Franco, Fidel-Rosales, Evelyn, Manrique, Diego, Mascaró-Zan, Jesús, Huamán-Castillón, Katia Medalith, Chamorro–Espinoza, Scherlli E., Garayar–Peceros, Humberto, Ponce–López, Vania L., Sifuentes-Rosales, Jhesly, Alvarez-Risco, Aldo, Yáñez, Jaime A., Mejia, Christian R. 01 January 2021 (has links)
Self-medication impacts both negatively and positively the health of people, which has become evident during the COVID-19 pandemic. The study aimed to assess the prevalence of self-medicated drugs used for respiratory symptoms, as COVID-19 preventive, for its symptoms or once tested positive. To determine the perception of symptom relief and demographic variables that promote self-medication in Peru. We performed a cross-sectional, analytical, multicenter study in 3792 study respondents on the use, the reason for use, and perception of relief after the use of six drugs during the quarantine period. An online questionnaire was developed, pretested and submitted to the general public. Multivariable logistic regression was used to ascertain factors that influence an individual's desire to self-medicate, associations were considered significant at p < 0.05 and using region (coast, mountain and jungle) as cluster group. The majority of respondents self-medicated with acetaminophen for respiratory symptoms and mainly because they had a cold or flu. It was observed that all the surveyed drugs (acetaminophen, ibuprofen, azithromycin, penicillin, antiretrovirals and hydroxychloroquine) were consumed for various symptoms including: fever, fatigue, cough, sneezing, muscle pain, nasal congestion, sore throat, headache and breathing difficulty. Over 90% of respondents perceived relief of at least one symptom. Multivariable logistic regression showed that older people have a higher frequency of antiretroviral self-medication, respondents who currently have a job had a higher frequency of penicillin self-medication, and that respondents from the Andes consumed less acetaminophen, while the ones from the rainforest consumed it more. There were significant percentages of self-medication, including drugs without sufficient scientific evidence. Age, region where one lived and job status were variables associated with self-medication frequency. Continuous awareness and sensitization about the risks of self-medication are warranted. / Revisión por pares
296

Factores asociados a la muerte por COVID-19 en pacientes admitidos en un hospital público en Tacna, Perú

Hueda Zavaleta, Miguel Angel, copaja corzo, cesar augusto, Bardales Silva, Angel Fabrizzio, Barreto Rocchetti, Luis Guillermo, Flores Palacios, Rodrigo Jesús, Benites Zapata, Vicente Aleixandre 06 1900 (has links)
Objetivo: Describir las características demográficas, clínicas, laboratoriales y de tratamiento de pacientes hospitalizados por la COVID-19 y determinar los factores de riesgo de mortalidad hospitalaria. Materiales y métodos: Estudio de cohorte retrospectivo de pacientes adultos hospitalizados por la COVID-19. Se extrajeron datos demográficos, clínicos, laboratoriales y de tratamiento de las historias clínicas de pacientes que ingresaron al Hospital III Daniel Alcides Carrión de Tacna. Para el análisis de supervivencia se empleó el modelo de riesgos proporcionales de Cox y se calcularon los cocientes de riesgo instantáneos (HR) crudos y ajustados con sus respectivos intervalos de confianza al 95% (IC 95%). Resultados: Se evaluó a 351 pacientes, el 74,1% eran hombres; las comorbilidades más comunes fueron obesidad (31,6%), hipertensión (27,1%) y diabetes mellitus (24,5%). La mediana de tiempo de hospitalización fue 8 días (RIC: 4-15). El 32,9% falleció durante el seguimiento. El análisis multivariado mostró un aumento del riesgo de morir asociado a la edad ≥65 años, HR = 3,55 (IC 95%: 1,70-7,40); al incremento de lactato deshidrogenasa >720 U/L, HR = 2,08 (IC 95%: 1,34-3,22); y a la saturación de oxígeno por debajo del 90%, principalmente cuando fue menor al 80%, HR = 4,07 (IC 95%: 2,10-7,88). Además, el uso de colchicina en el tratamiento tuvo un efecto protector, HR = 0,46 (IC 95%: 0,23-0,91). Conclusiones: Los factores de riesgo de muerte por la COVID-19 incluyeron ser mayor de 65 años, tener saturación de oxígeno menor de 90% y elevación del lactato deshidrogenasa >720 U/L; el tratamiento con colchicina podría mejorar el pronóstico de los pacientes.
297

Distanční forma výuky tělesné výchovy v době pandemie SARS-CoV-2 / Distance form of teaching physical education during the pandemie SARS-CoV-2

Čudová, Martina January 2021 (has links)
Title: Distance form of teaching physical education during the pandemic SARS- CoV-2. Aims: The aim of this work was to determine the course and provision of physical education in the time of the SARS-CoV-2 pandemic from 1 January 2020 to 31 December 2020. Methods: An online questionnaire was used to write the work, which was shared with teachers via social networks and via email. CAWI method was used for data collection. The data were subsequently processed using MS Excel 2013. Results: The results show that in the spring the teaching of physical education took place much less and less often than in the autumn. In the spring, the teachers did not yet have such technical equipment compared to the autumn, and the teaching took place mainly in an offline form. In the autumn, more teachers taught online, focusing mainly on motivating children to move. In the spring part, the teaching was more theoretically focused. Respondents agreed that a failure in physical education will have a major impact on children's development in the future. Keywords: SARS-CoV-2, distance learning, physical education, government measures, pandemic
298

Epidemiology and Characteristics of Pediatric COVID-19 Cases Among UMass Memorial Health Care Patients

Fahey, Nisha 26 April 2021 (has links)
Background: The epidemiology of SARS-CoV-2 infection in the pediatric population, with a focus on racial and ethnic disparities and impact of societal public health measures, remains poorly understood. Methods: This large observational study used electronically abstracted data from pediatric (≤ 19 years of age) patients who received a molecular test for SARS-CoV-2 at a UMass Memorial Health Care (UMMHC) site between March 8, 2020 and April 3, 2021 which was further supplemented by manual chart review of a subset of pediatric SARS-CoV-2 cases. Multivariable logistic regression models with interaction terms were used to identify risk factors for SARS-CoV-2 infection. Segmented regression analysis using Poisson models was used to estimate the effect of public health measures on the weekly incidence of SARS-CoV-2 infection. Results: A total of 25,426 unique pediatric patients were tested for SARS-CoV-2 among whom 2,920 (11.5%) tested positive. The average age of those who tested positive was 10.8 years (SD: 5.8) and 48.1% were female. In the subset analysis, nearly three-quarters (75.9%) of SARS-CoV-2 diagnoses occurred through a telephone encounter, meaning that the child was not physically examined by a provider prior diagnosis and only 2.0% were admitted for inpatient care at diagnosis. Results of multivariable regression revealed that children or parents who self-reported Black race, Hispanic ethnicity, and non-English primary language were associated with approximately twice the odds of testing positive in comparison with White or English-speaking patients. Furthermore, increasing age was associated with increased odds of testing positive for SARS-CoV-2 (aOR: 1.1 (1-4 years), 1.2 (5-9 years), 1.4 (10-14 years), 1.6 (15-17 years), 1.7 (18-19 years)). However, this association between age and positivity rate, varies by race/ethnicity and primary language such that Non-Hispanic Black, Hispanic, and non-English speaking children had markedly greater odds of testing positive during adolescence in comparison to Non-Hispanic White and English-speaking counterparts. Results from segmented regression analysis demonstrated a decline in weekly incidence of cases 9.9% (95% CI: 7.8 – 11.9) after the Massachusetts state mask mandate was implemented. During the winter holidays, the rate of increase in the weekly incidence of cases was 12.1% (95% CI: 11.9 – 12.3) in this pediatric population. Conclusions: Many SARS-CoV-2 cases have been diagnosed at UMMHC sites and notable racial/ethnic disparities exist that vary based on patient age. Public health measures are effective at preventing transmission of SARS-CoV-2 among children.
299

Working From Home, The New Normal? : A qualitative study of the working from home phenomenon’s future, through an international perspective.

Ottosson, Tanya, Back, Emelie January 2021 (has links)
During the past two years, the pandemic of the SARS-CoV-2 virus has impacted where a big share of the world’s employees conducts their work. Governments around the world have encouraged people to stay at home as much as possible, in the hope of slowing down the infection rate of the virus. Companies around the world have therefore encouraged their employees to work from home. The change has been rapid and unusual for a lot of people. The purpose of this thesis is to examine what the effects of working from home has had on employees and what parameters may make it sustainable long-term. When investigating this matter further, a set of sub-questions has been identified in hope to obtain a deeper understanding of the topic and to answer the question of How can working from home be sustainable long-term? This paper is a qualitative research that follows an inductive approach. The literature review provides relevant theoretical background, which has then been the foundation for the analysis and conclusion. The theories provided covers leadership, motivation, efficiency, gender equality, government support, and internationalization. The conceptual framework then provides a deeper understanding of how each of these theories relates to the main question and its sub-questions. The authors have then examined secondary data such as articles from trusted journals as well as government records in a systematic literature review. An analysis of the findings in the systematic literature review in correlation to the theories has then been made to each sub-question. The concluding chapter then ties the thesis by answering the main question of this subject.
300

“Let me be absolutely clear: this cannot be business as usual.” - A Case Study of the Securitisation of SARS-CoV-2 in the European Union

Waldeck, Benjamin January 2021 (has links)
As a global phenomenon, the outbreak of SARS-CoV-2 has impacted the socio-economic and political life like no other event of the recent past. With over 600,000 fatalities in its member-states, an unprecedented economic recession and damage to the Single Market, the European Union has been hit unexpectedly hard by COVID-19. Through the lens of Securitisation, and more precisely, Collective Securitisation, this thesis has the purpose to examine how the EU and its institutions have responded to the threat that is the spread of SARS-CoV-2, asking ‘Has SARS-CoV-2 been successfully securitised in the European Union?’. By applying a qualitative content analysis to speeches of the European Commission published between January and May 2020 as well as to a European Parliament Plenary debate following the speech of Commission President von der Leyen on April 16th, 2020, the thesis establishes that securitising moves have taken place in the examined timeframe and that they have been accepted by the European Parliament. In accordance with the Copenhagen School framework of Securitisation and Sperling and Webber’s Collective Securitisation model, the thesis concludes that COVID-19 was therefore successfully securitised.

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