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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.
11

Mitral Valve Prolapse: Cardiac Arrest With Long-Term Survival

Boudoulas, Harisios, Schaal, Stephen F., Stang, John M., Fontana, Mary E., Kolibash, Albert J., Wooley, Charles F. 01 January 1990 (has links)
Cardiac arrest has been reported in patients with mitral valve prolapse; however, clinical characteristics and survival information are limited since most of the cases reported include autopsy data. Nine patients (2 male, 7 female) with mitral valve prolapse were identified who had cardiac arrest; ventricular fibrillation was documented in 8 patients; resuscitation was unsuccessful in 2. Eight had a history of palpitations (months to 15 years duration) and ventricular arrhythmias, 3 had a history (5-15 years) of recurrent syncope, and 1 was totally asymptomatic. Cardiac catheterization-angiographic studies in 8 patients demonstrated normal coronary artery anatomy and mitral valve prolapse. All 9 patients had auscultatory and echocardiographic evidence of mitral valve prolapse. Seven survivors (6 still alive) were followed from 3 to 14 years after cardiac arrest. A subset of patients with mitral valve prolapse and cardiac arrest is described in whom past medical history is compatible with cardiac arrhythmias or syncope, and whose long-term prognosis appears better than patients with other causes of cardiac arrest.
12

Sudden Death and Isolated Right Ventricular Noncompaction Cardiomyopathy: Report of 2 Autopsied Adult Cases

Ilyas, Sadaf, Ganote, Charles, Lajoie, Dawn, Robertson, Julie, Cline-Parhamovich, Karen 01 September 2013 (has links)
A predominantly right ventricular variant of isolated noncompaction cardiomyopathy is a potentially lethal disease entity, which only recently has become recognized in the clinical and cardiac imaging literature. There are currently few established morphologic criteria for the diagnosis other than right ventricular dilation and presence of excessive regional trabeculation. To date, there have been no autopsy reports of cases following either clinical diagnosis or sudden death. We report 2 adult cases of sudden unexpected death in which unexplained right ventricular dilation and prominent apical hypertrabeculation were the principal findings. The gross and microscopic results suggest pathological similarities between, or coexistence of, right ventricular noncompaction and arrhythmogenic right ventricular cardiomyopathies.
13

Sudden Death and Isolated Right Ventricular Noncompaction Cardiomyopathy: Report of 2 Autopsied Adult Cases

Ilyas, Sadaf, Ganote, Charles, Lajoie, Dawn, Robertson, Julie, Cline-Parhamovich, Karen 01 September 2013 (has links)
A predominantly right ventricular variant of isolated noncompaction cardiomyopathy is a potentially lethal disease entity, which only recently has become recognized in the clinical and cardiac imaging literature. There are currently few established morphologic criteria for the diagnosis other than right ventricular dilation and presence of excessive regional trabeculation. To date, there have been no autopsy reports of cases following either clinical diagnosis or sudden death. We report 2 adult cases of sudden unexpected death in which unexplained right ventricular dilation and prominent apical hypertrabeculation were the principal findings. The gross and microscopic results suggest pathological similarities between, or coexistence of, right ventricular noncompaction and arrhythmogenic right ventricular cardiomyopathies.
14

EVALUATION OF SOYBEAN DISEASES AND PESTS USING TWO ADVANCED BREEDING POPULATIONS

Lee, Yi-Chen 01 September 2021 (has links) (PDF)
Soybean (Glycine max [L.] Merr.) is one of the most important crops in the world. The average annual yield losses due to soybean diseases and pests are estimated to be around 11% in the United States. Soybean yield losses due to sudden death syndrome (SDS), caused by the fungus Fusarium virguliforme O'Donnell & T. Aoki have been problematic in majority of the soybean producing states. In recent years, reniform nematode (RN, Rotylenchulus reniformis Linford and Oliveira) and frogeye leaf spot (FLS), caused by the fungus Cercospora sojina K. Hara have emerged as a major problem in the southern soybean producing states. Planting resistant cultivars is one of the most cost-efficient methods in managing SDS, RN, and FLS, therefore it would be critical to identify and map the quantitative trait loci (QTL) that underlie their resistances. Two soybean populations were evaluated in this study. The ‘Essex’ × ‘Forrest’ 77 near-isogenic lines were screened in the field to evaluate the disease index of SDS. The Essex × Forrest and ‘Flyer’ × ‘Hartwig’ recombinant inbred lines were screened in the greenhouse to assess the reproduction index of RN and the disease severity of FLS. The BARCSoySNP6k chip was used to genotype the two populations. Four QTL that underlie SDS resistances were mapped in the same region as Rfv06-01, Rfv06-02, Rfv13-01, and Rfv19-01. The Rfv06-02 interval in this study was smaller than the one previously reported. Rrr08-01, Rrr13-01, Rrr15-01, Rrr18-01, and Rrr18-02 were reported to confer resistances to RN. Rrr08-01, Rrr13-01 and Rrr15-01 were novel whereas Rrr18-01, and Rrr18-02 were mapped in previous studies. cqSCN-001 (soybean cyst nematode, Heterodera glycines Ichinohe) was identified in the same region as Rrr18-01, and Rrr18-02 whereas cqSCN-006 was identified in the same region as Rrr15-01. These findings provide further evidence that there are common sources of genetic resistances to RN and SCN. Rcs15-01 and Rcs15-02 were reported to confer resistances to FLS. Rcs15-01 was novel and Rcs15-02 was mapped at the same region as an Rcs mapped in a previous study. This indicated that Rcs15-02 has dual resistances to C. sojina races. Candidate genes were inferred in this study. The QTL mapped in this study could potentially be used in soybean breeding programs that aim to introgress genetic resources that confer resistances to SDS, RN, and FLS.
15

ASSESSMENT OF SUDDEN DEATH SYNDROME BY UTILIZING UNMANNED AERIAL VEHICLES AND MULTISPECTRAL IMAGERY

McKinzie, Lindsey 01 May 2022 (has links)
Fusarium virguliforme is a soil-borne pathogen that is the causal agent of sudden death syndrome (SDS). This disease is one of the top contributors to major yield losses in soybean across the United States. Characteristic symptoms of the disease include interveinal chlorosis and/or necrosis of trifoliate leaves and defoliation. In some cases, the foliar symptoms may not be present, but yield loss still occurs. This disease is evaluated using an incidence rating, the percent of plants in the plot that are expressing symptoms, and a severity rating, using a one to nine scale based on varying levels of chlorosis, necrosis, and defoliation. Using remote sensing provides an alternate approach to identify and evaluate plant diseases. It provides a non-destructive method to assess the severity of foliar symptoms and their distribution across production fields. SDS was chosen as the disease to use for this system due to the unique disease symptomology and yield loss. In 2019 and 2020, SDS trials were established in a production field location that has a history of SDS in Valmeyer, IL. This seed treatment study had different chemicals with varying levels of efficacy against SDS. Disease ratings were collected at the first sign of symptoms, and aerial imagery was collected on the same day. There were multiple dates across both years when this data was collected. ArcGIS was used to analyze the multispectral imagery and do a plot by plot analysis for each of the plots. A regression analysis was performed to test the relationship between the foliar disease ratings and the plot data collected from the multispectral imagery. Multiple vegetation indices were tested, and the results showed that overall, in 2019, GNDVI had the strongest relationship with foliar ratings. In 2020, NDRE had the strongest overall relationship with foliar ratings. The relationship between NDVI and the ratings was the most consistent at the last rating of the season.
16

Effect of Fusarium virguliforme and Heterodera glycines on soybean

Brzostowski, Lillian Frances January 1900 (has links)
Master of Science / Department of Agronomy / William T. Schapaugh Jr / Fusarium virguliforme, the soilborne fungus which causes sudden death syndrome (SDS) of soybean, and Heterodera glycines Ichinohe, soybean cyst nematode (SCN), are two economically important pathogens in the Midwest. The pathogens are often found together in soybean (Glycine max (L.) Merr.) fields. This study was conducted to determine the effect of soybean genotype, F. virguliforme populations, and H. glycines populations have upon yield and to examine the interaction between the two pathogens. In 2008 and 2009, four genotypes with different levels of resistance to SDS and H. glycines were planted at seven environments. F. virguliforme and H. glycines soil populations were quantified at planting, midseason, and harvest. At the end of the growing season, area under the disease progress curves of SDS, F. virguliforme root populations, and H. glycines reproductive indices were determined and plots harvested for seed yield. Soil populations of F. virguliforme and H. glycines at planting, midseason, and harvest varied across environments. Within environments, generally, they were not significantly different. Seed yield varied within and across environments. As disease pressure increased, the performance of resistant genotypes increased compared to susceptible genotypes. Genotypes resistant to SDS yielded higher than susceptible genotypes. There were negative correlations between yield and disease rating and F. virguliforme root populations. F. virguliforme soil populations and H. glycines populations at planting were positively correlated. It is important to manage both SDS and H. glycines in fields with a history of the two diseases. This can be achieved through genetic resistance. Information in this study will improve decisions regarding genotype selection to minimize losses to SDS and H. glycines.
17

Situationen för anhöriga och sjuksköterskan vid plötsligt dödsfall – en litteraturöversikt / The situation for the relatives and the nurse at the sudden death - a literature review

Eriksson, Elina, Eriksson, Kristina January 2016 (has links)
Bakgrund: Att förlora en anhörig är något som är väldigt traumatiskt och omtumlande. Reaktioner på krisen brukar visa sig enligt olika faser, dessa är chockfasen, reaktionsfasen, bearbetning- och reperationsfasen samt nyorienteringsfasen. Det är viktigt att kommunikationen är ärlig och ska alltid vara hjälpande för patienten eller anhöriga. Syfte: Syftet med den här studien är att sammanställa befintliga vetenskapliga artiklar för att belysa situationen för anhöriga och personal vid plötsligt dödsfall. Metod: En litteraturstudie gjordes som baserades på 13st vetenskapliga artiklar. Litteratursökningen gjordes med hjälp av databaserna CINAHL och PubMed. Resultat: Resultatet av studien visade på att anhöriga behövde olika stöd i olika stadier och att informationen gavs på ett så rakt och ärligt sätt. Personalen upplevde att utbildning var viktigt för hantering av omhändertagande och att de sökte stöd och kunskap hos mer erfarna kollegor. Slutsats: Informationen om dödsorsaken till de anhöriga var mycket viktig och att personalen var öppna och ärliga. Anhöriga uppskattade att personalen fanns tillgängliga. Att som sjuksköterska ha tillräcklig utbildning gör att självförtroende ökar och hanteringen av svåra situationer underlättas samt kunskapen hjälper att kunna stödja anhöriga bättre. / Background: Losing a loved one is something that is very traumatic and bewildering. Reactions to the crisis usually appear under different phases, these are the shock phase, reaction phase, processing- and repair phase and reorientation phase. It is important that communication is honest and that it always will be helping for the patient or the relatives. Purpose: The purpose of this study is to compile existing research articles to highlight the situation of family members and staff of sudden death. Method: A literature review conceders on 13 scientific articles. The literature search conceders the databases CINAHL and PubMed. Results: The results of the study showed that relatives needed different support at different stages and that the information is given in such a straight and honest way as possible. Staff felt that education was important for the management of care and that they sought the support and expertise of more experienced colleagues. Conclusion: The information about the cause of death to the families was very important and that the staff were open and honest. Relatives appreciated that the staff were available. Nurses that have sufficient training increases self-confidence enables the handling of difficult situations and knowledge will help to support families better.
18

När döden sker plötsligt och oväntat : Sjuksköterskans upplevelser av situationen

Schön, Erika, Sandblad, Michelle January 2016 (has links)
Plötslig och oväntad död är något sjuksköterskan kan komma att uppleva i sitt yrkesverksamma liv. Plötslig och oväntad död innebär att en person avlider oväntat och att döden inträffar upp till 24 timmar efter symtomdebut, oberoende på om tidigare symtom på bakomliggande sjukdom är känd. Syftet med studien var att belysa sjuksköterskans upplevelser av patienters plötsliga och oväntade död. Det gjordes genom en litteraturstudie som innebär att på ett systematisk sätt identifiera och undersöka vetenskapliga artiklar. Många sjuksköterskor upplever känslor såsom sorg, skuld och otillräcklighet vid patienters plötsliga och oväntade död. Det är först när rätt tid och plats ges som sjuksköterskan får lov att ge utlopp för sina känslor. Dessutom har anhörigas reaktioner en stark inverkan på sjuksköterskans upplevelse av den egna kapaciteten. Copingstrategier är av vikt, både för att kunna möta anhöriga men även för att kunna hantera de egna känslorna. Mer forskning bör genomföras eftersom att plötslig och oväntad död är en händelse som upplevs vara svårhanterlig för sjuksköterskan. Också utbildning i hanteringen av plötsliga och oväntade dödsfall är av betydelse då det är något som sjuksköterskan kan komma att ställas inför och på grund av att kunskapen inom ämnet är bristfällig. / Sudden and unexpected death is something that the nurse may experience in his or her professional life. Sudden and unexpected death means that a person dies unexpectedly and that the death occurs within 24 hours after the first symptoms, regardless whether an underlying disease is known. The purpose of this study was to elucidate the nurses’ experience of patients sudden and unexpected death. This was done by a literature research which means that in a systematic way identify and examine scientific articles. Many nurses are experiencing feelings such as grief, guilt and inadequacy when a patient sudden and unexpected dies. It is only when the right time and place is given that the nurse is allowed to vent his or her own feelings. In addition, the reactions from relatives have a strong impact on the nurse’s experience of his or her own capacity. Coping strategies are of importance, both in beeing able to meet relatives but also to be able to manage his or her own emotions. More research should be conducted since sudden and unexpected death is an event that is perceived as difficult to handle for the nurse. Education in handling sudden and unexpected deaths is of importance since it is something that the nurse probably will encounter and because the knowledge within the subject is inadequate.
19

Emaranhamento multicor para redes de informação quântica / Multicolor entanglement for quantum information network.

Coelho, Antonio Sales Oliveira 19 April 2013 (has links)
Apresentamos nesta tese a primeira geração direta de emaranhamento tripartite entre feixes intensos de luz. Medimos o emaranhamento entre os feixes sinal, complementar e bombeio refletido, produzidos por um Oscilador Paramétrico Ótico (OPO) operando acima do limiar de oscilação. A principal característica do nosso sistema é a diferença entre os comprimentos de onda dos campos (l0 = 532.251 nm, l1 = 1062.102 nm, e l2 = 1066.915 nm). Esta é a primeira medida de emaranhamento entre mais de dois subsistemas produzidos por uma única fonte no âmbito de variáveis contínuas. Para investigar a existência emaranhamento, utilizamos o critério de positividade sob transposição parcial (PPT). Este critério, aplicado a sistemas compostos por estados gaussianos, dispostos em bipartições do tipo 1×(N 1), torna-se necessário e suficiente na demonstração do emaranhamento. Realizamos também a caracterização do emaranhamento produzido quando submetemos os campos a perdas, identificando regiões de parâmetros onde os estados apresentam emaranhamento frágil ou robusto. A fim de garantir que estamos lidando com estados gaussianos, investigamos a estatística das flutuações dos campos, mostrando excelente acordo entre os valores dos momentos de ordem mais alta da fotocorrente medida e os valores esperados para uma distribuição gaussiana. O estudo que apresentamos é um passo importante para a elaboração de uma rede de informação quântica que possibilitará a comunicação entre diferentes sistemas físicos. / We present in this thesis the first direct generation of tripartite entanglement among bright beams of light. We measured the entanglement among signal, idler and reflected pump beams, produced by an Optical Parametric Oscillator (OPO) operating above the threshold. The main feature of our system is the difference between the wavelengths of the fields (l0 = 532.251 nm, l1 = 1062.102 nm, e l2 = 1066.915 nm). This is the first measurement of entanglement among more than two subsystems produced by a single source, in a continuous variable system. In order to investigate the existence of entanglement, we applied the criterion of positivity under partial transposition (PPT). This criterion, applied to systems composed of Gaussian states, arranged in 1×(N1) bipartition, becomes necessary and sufficient to demonstrate entanglement. We also characterized the entanglement when the fields are submitted to losses, identifying regions of parameters where the states have fragile or robust entanglement. To ensure that we are dealing with Gaussian states, we investigate the statistics of the fields, showing excelent agreement among values of higher order moments of the photocurrent measured and expected values for a Gaussian distribution. The present study is an important step in the development of a quantum information network formed by different physical systems.
20

Determinação da sensibilidade do barorreflexo na estratificação de risco de eventos arrítmicos na doença de Chagas / Determination of baroreflex sensitivity in the risk stratification for arrhythmic events in Chagas disease

Santos, Astrid Rocha Meireles 16 April 2010 (has links)
Introdução: A morte súbita é a principal causa de morte na doença de Chagas, correspondendo de 55 a 65% dos casos. Observa-se que parte destas, ocorre em pacientes com função ventricular esquerda (FEVE) preservada, levando a acreditar que fatores desestabilizadores do substrato arritmogênico exercem um importante papel nestes eventos. Evidências já demonstraram a depressão parassimpática como fator contribuinte na gênese de arritmias diversas em presença de cardiopatia isquêmica. Assim, insiste-se na necessidade de se identificar precocemente quais os pacientes, no contexto da cardiopatia chagásica crônica, apresentam risco aumentado para o desenvolvimento de eventos arrítmicos complexos. Acredita-se que a avaliação autonômica identifique subgrupos distintos de risco. O presente estudo teve como objetivo determinar a sensibilidade do barorreflexo (SBR) em pacientes com doença de Chagas, nas formas indeterminada (GI) e arritmogênica com taquicardia ventricular não sustentada (GII) e com taquicardia ventricular sustentada (GIII) e, secundariamente, avaliar a associação entre a severidade da arritmia ventricular com o grau de comprometimento da SBR. Métodos: 42 pacientes foram submetidos à monitorização cardiovascular não invasiva pelo sistema Task Force ® onde foi determinada a SBR, utilizando o método da fenilefrina e analisada a variabilidade da frequência cardíaca (VFC) no domínio do tempo por meio da eletrocardiografia dinâmica de 24horas e a FEVE, por meio da ecocardiografia. Resultados: Observou-se diferença estatística significativa entre os grupos em relação à SBR em resposta à fenilefrina. O GIII apresentou o menor valor de SBR (6,09 ms/mmHg) quando comparado aos GII (11,84ms/mmHg) e GI (15,23ms/mmHg). Após comparação múltipla entre os grupos, verificou-se diferença significativa entre GI e GIII (p= 0,01). Quando se correlacionou SBR e densidade de extra-sístoles ventriculares (EV), observou-se que todos os pacientes portadores de baixa densidade de EV (< 10/hora) apresentavam SBR preservada (6,1ms/mmHg).Em contrapartida, entre aqueles com alta densidade de EV (>10/hora) somente 59% tinham SBR preservada (p=0,003). Nos pacientes com SBR deprimida (3,0-6,0 ms/mmHg) houve maior densidade de EV (p=0,01). Pacientes com SBR preservada apresentaram tanto função ventricular normal como moderadamente comprometida (66,7% com FEVE<40% e 79,5% com FEVE40%; p=0,62). O mesmo observou-se em pacientes com SBR moderadamente deprimida, (15,4% com FEVE<40% e 33,3% com FEVE40%; p=0,46). Não foi verificada correlação entre SBR e VFC. Ao se aplicar o modelo de regressão logística, observou-se que somente a SBR influenciou o aparecimento da taquicardia ventricular sustentada (p=0.028). Conclusão: A SBR está preservada na forma indeterminada da doença de Chagas e diminuída na forma arritmogênica. O comprometimento da SBR é progressivo e acompanha a evolução da doença, sendo mais intenso nos pacientes com arritmias ventriculares mais complexas. O grau de disfunção autonômica não se correlacionou com a função ventricular, mas, sim, com a densidade e a complexidade das arritmias / Introduction: Sudden death is the main cause of death in Chagas disease, corresponding to 55 to 65% of the cases. Some of these occur in patients with normal or almost normal left ventricular function (LVF), leading us to believe that factors that destabilize the arrhythmogenic substrate play an important role in these events. Evidences show parasympathetic depression to be a contributing factor in the genesis of diverse arrhythmias in the presence of ischemic heart disease. Thus, we insist on the need of an early identification of the patients, in the context of chronic Chagas heart disease, that are at increased risk of developing complex arrhythmic events. It is possible that autonomic assessment allows the identification of distinct risk subgroups. The objective of this study was to determine the baroreflex sensitivity (BRS) in patients with the indeterminate form of Chagas disease, (GI), and with the arrhythmogenic form of Chagas disease with nonsustained ventricular tachycardia (GII) and sustained ventricular tachycardia (GIII) and to assess the correlation between the severity of ventricular arrhythmia and the degree of BRS impairment. Methods: Forty-two patients were subjected to noninvasive cardiovascular monitoring using the Task Force® system. The phenylephrine method was used to determine BRS, 24- hour dynamic electrocardiography was used to analyze heart rate variability (HRV) over time and echocardiography was used to determine LVF. Results: A statistical difference was observed between the groups regarding their BRS to phenylephrine. GIII presented the lowest BRS value (6.09 ms/mmHg) when compared with GII (11.84ms/mmHg) and GI (15.23ms/mmHg). After multiple comparisons among the groups, a significant difference was found between GI and GIII (p=0.01). When BRS was correlated with ventricular extrasystole (VE) density, all patients who had low VE density (<10/hour) had preserved BRS (6.1ms/mmHg). On the other hand, only 59% of those with high EV density (>10/hour) had preserved BRS (p=0.003). In patients with moderately depressed BRS (3.0-6.0 ms/mmHg) there was a greater density of EV (p=0.01). Patients with preserved BRS had preserved or moderately compromised LVF (66.7% with LVF<40% and 79.5% with LVF40%; p=0.62) as had patients with moderately depressed BRS (15.4% with LVF<40% and 33.3% with LVF40%; p=0.46). There was no correlation between BRS and LVF. When the logistic regression model was applied, only BRS influenced the presence of sustained ventricular tachycardia (p=0.028). Conclusion: BRS is preserved in indeterminate Chagas disease and diminished in the arrhythmogenic form. The BRS impairment is progressive as the disease progresses, being more evident in patients with more complex ventricular arrhythmias. The degree of autonomic dysfunction did not correlate with ventricular function but with the density and complexity of the arrhythmias

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