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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.
371

Digital Signal Processing and Display of Lung Sounds

Pasika, Hugh 04 1900 (has links)
Presented here is an examination of the issues surrounding the analysis of lung sounds and their display. The project is aimed at providing a visual representation of the information that a physician gleans from auscultation of the lungs. Such a tool would be of benefit to those who are hearing impaired and also in teaching auscultation. A second goal is to provide a tool that will allow the examination and quantification of lung sounds thus permitting linkage between the acoustic events and their physical causes. The project is divided into two tasks. The first is the isolation of the wheezes and crackles; the second is their display. The isolation problem is difficult due to the variance in the frequency characteristics of the sounds; wheezes may appear anywhere in a two thousand hertz band and crackles also display a varying spectrum. The difficulty in separation is further compounded by the spectral overlap of the two. These problems preclude any 'simple' filter solution. In order to separate the sounds, filtering methods based on exploiting the statistical differences namely the stationarity of the wheeze and non-stationarity of the crackle are utilized. Of the several methods attempted, the most promising was the Adaptive Line Enhancement process when driven by the Least Mean Squares adaptive algorithm. An important criteria for being able to display the sounds was to access their temporal information. Accomplishing this with the standard short time Fourier transform precludes adequate resolution to identify the frequency characteristics of crackles. Display of the crackle information was facilitated by the use of high resolution time-frequency methods based on Cohen's Class of time-frequency representations. These methods are able to simultaneously provide high time and frequency resolution. A method for automatic adjustment of the parameters involved in the process was developed in order to yield the best display possible. / Thesis / Master of Engineering (ME)
372

Reimagining the Transplant Evaluation Process: A review of the Ethical and Evidentiary Basis Behind the Psychosocial Evaluation of Lung Transplantation

Davis, Hugh Alexander 08 1900 (has links)
Despite decades of changes in allocation policies for lung transplantation, the field is plagued by outdated and ethically problematic processes that impact candidate selection. Transplant centers screen potential organ recipients with a psychosocial evaluation in an attempt to identify potential barriers to post transplant success. Professional guidelines note the problematic nature of basing transplant candidacy on social factors. The prohibitive nature of the process in conjunction with the coercive pressures of impending demise forces individuals and their social support systems to make concessions that directly impact their individual dignities. Precluding eligible candidates based upon nonadherence does not improve clinical outcomes and thus does not benefit the net population. Psychosocial evaluation needs to be reimagined. The current practice, as it stands, fails to meet national ethical standards, but with its diverse widespread utilization, the psychosocial evaluation can become a tool to identify potential gaps and empower transplant teams to support individuals in addressing perceived deficiencies. / Urban Bioethics
373

Membrane Type MMPs Show Differential Expression in Non-Small Cell Lung Cancer (NSCLC) Compared to Normal Lung; Correlation of MMP-14 mRNA Expression and Proteolytic Activity.

Atkinson, Jennifer M., Gill, Jason H., Loadman, Paul, Martin, Sandie W., Pennington, J., Anikin, V.A., Mearns, A.J., Edwards, D.R. January 2007 (has links)
No / Improved understanding of the involvement of matrix metalloproteinases (MMPs), including membrane-type MMPs (MT-MMPs), in human tumours has potential diagnostic, prognostic and therapeutic implications. We assessed the relationship between MT-MMP expression and clinicopathological parameters in human non-small cell lung cancer (NSCLC) and histologically normal lung tissue by quantitative Real Time PCR (qRT-PCR). All MT-MMPs (MMPs 14-17, 24 and 25) were detected by qRT-PCR with significantly higher MMP-14, -15 and -17 expression observed in tumour relative to normal lung specimens. MMP-16 was undetectable in normal lung but expressed in 8% tumours. MMP-15 demonstrated significant overexpression in adenocarcinomas relative to squamous cell carcinomas and normal lung tissue. MMP-14 mRNA expression strongly correlated to MMP-14 proteolytic activity in preclinical tumour models, indicating that qRT-PCR may predict MMP-14 activity levels in NSCLC. These data suggest that MMP-14, -15 and -17 may be good markers of disease, or therapeutic targets for treatment of human NSCLC.
374

The Lived Experiences of Caregivers of Lung Transplant Recipients

Glaze, Joy Adella 02 March 2018 (has links)
Lung transplantation is a treatment for patients with end stage lung disease; they will not survive without such surgery. A caregiver is essential for a patient to become eligible for a lung transplant and the caregiver plays an essential role in the transplant recipient’s care both before and after transplant surgery. Most caregiver research has been conducted on caregivers of persons with Alzheimer’s disease, dementia or on elderly patients, however, it is important to examine caregivers’ experiences caring for other patient groups with disabling conditions. Caregivers of transplant recipients are one such group. The purpose of this qualitative study, using a hermeneutic phenomenological approach, was to examine the lived experiences of caregivers of lung transplant recipients pre- and post-lung transplantation. The study used semi- structured, face to face, tape recorded in- depth interviews to document the experiences of a purposive sampling of 20 caregivers of lung transplant recipients. Interviews (English, Spanish) were transcribed verbatim and analyzed for emerging themes. The resulting 4 themes and 12 sub themes were: 1) Establishing the diagnosis; 2) Caregivers roles; 3) Caregivers psychological and psychosocial Issues; and 4) Support. The 12 sub themes were:1) Caregivers reaction to transplant option; 2) Caregivers’ lack of basic knowledge as related to lung transplant 3) Disease progression: Reality of unanticipated changes/fear of death; 4) Pre- transplant experiences; 5) Hospital course; 6) Home care; 7) Lifestyle changes and Social activities;8) Physical health and Emotional health ; 9) Financial and Employment issues;10) Family/Friends;11) Professional support; 12) Support groups. Study results demonstrated caregivers’ lack of knowledge about transplantation, dramatic changes in caregivers ‘family life, social activities, employment, and often financial status. Results also demonstrated a need for health care providers and policy makers to recognize caregivers’ stressful life changes and implement informational, psychological and emotional interventions and policies to assist these caregivers during their stressful and tedious experiences.
375

L’utilisation de l’échographie pulmonaire dans la prise en charge des patients de soins critiques

Piette, Eric 05 1900 (has links)
En démontrant sa capacité d’identifier les pneumothorax, de différencier les différentes causes d’insuffisance respiratoire chez les patients dyspnéiques et de confirmer la position d’un tube endotrachéal lors d’une intubation endotrachéale, l’échographie pulmonaire a pris une place prépondérante dans la prise en charge des patients de soins critiques. La majorité des études, notamment celles sur l’intubation endotrachéale, ont évalué la performance de cliniciens possédant une expérience considérable en échographie pulmonaire et souvent dans un cadre idéal permettant des examens d’une durée prolongée. Considérant la disponibilité grandissante de l’échographie ciblée lors des situations de stabilisation et de réanimation des patients de soins critiques, nous voulions évaluer la capacité d’un groupe de clinicien hétérogène en termes de formation échographique à identifier la présence ou l’absence de glissement pleural sur de courtes séquences (comparable à la durée probable d’un examen lors de condition de réanimation) d’échographie pulmonaire enregistrées chez des patients intubés. Un total de 280 courtes séquences (entre 4 et 7 secondes) d’échographie pulmonaire démontrant la présence ou l’absence de glissement pleural chez des patients intubés en salle d’opération ont été enregistrées puis présentées de façon aléatoire à deux groupes de cliniciens en médecine d’urgence. Le deuxième groupe avait la possibilité de s’abstenir advenant une incertitude de leur réponse. Nous avons comparé la performance selon le niveau de formation académique et échographique. Le taux moyen d’identification adéquate de la présence ou l’absence du glissement pleural par participant était de 67,5% (IC 95% : 65,7-69,4) dans le premier groupe et 73,1% (IC 95% : 70,7-75,5) dans le second (p<0,001). Le taux médian de réponse adéquate pour chacune des 280 séquences était de 74,0% (EIQ : 48,0-90,0) dans le premier groupe et 83,7% (EIQ : 53,3-96,2) dans le deuxième (p=0,006). Le taux d’identification adéquate de la présence ou absence d’un glissement pleural par les participants des deux groupes était nettement supérieur pour les séquences de l’hémithorax droit par rapport à celles de l’hémithorax gauche (p=0,001). Lorsque des médecins de formation académique et échographique variable utilisent de courtes séquences d’échographie pulmonaire (plus représentatives de l’utilisation réelle en clinique), le taux d’identification adéquate de la présence ou l’absence de glissement pleural est plus élevé lorsque les participants ont la possibilité de s’abstenir en cas de doute quant à leur réponse. Le taux de bonnes réponses est également plus élevé pour les séquences de l’hémithorax droit, probablement dû à la présence sous-jacente du cœur à gauche, la plus petite taille du poumon gauche et l’effet accru du pouls pulmonaire dans l’hémithorax gauche. Considérant ces trouvailles, la prudence est de mise lors de l’utilisation de l’identification du glissement pleural sur de courtes séquences échographique comme méthode de vérification de la position d’un tube endotrachéal lors d’une intubation endotrachéale, et ce, particulièrement pour l’hémithorax gauche. Aussi, une attention particulière devrait être mise sur la reconnaissance du pouls pulmonaire lors de l’enseignement de l’échographie pulmonaire. / The field of targeted lung ultrasound in critical care is in constant expansion. Its many proven use include pneumothorax diagnosis, differentiation of the different causes of acute dyspnoea and endotracheal intubation confirmation. These studies on endotracheal intubation evaluated sonographers with extensive ultrasound training using sometimes lengthy exam. Hence, with the growing presence of bedside lung ultrasound we devised a study to evaluate the capacity of a heterogeneous group of physicians, with different levels of ultrasound training, to correctly identify lung sliding on random short sequences of recorded thoracic ultrasound. 280 short ultrasound sequences (4 to 7 seconds) of present and absent lung sliding of intubated patients recorded in the operating room were randomly presented to 2 groups of physicians. Descriptive data, mean accuracy of each participant, as well as the rate of correct answers for each of the sequences was measured and compared for different subgroups. Participants in the second group where instructed that they could abstain from answering in uncertain cases. Mean accuracy was 67.5% (95%CI: 65.7-69.4) in the first group and 73.1% (95%CI: 70.7-75.5) in the second (p<0.001). When considering each sequence individually, median accuracy was 74.0% (IQR: 48.0-90.0) in the first group and 83.7% (IQR: 53.3-96.2) in the second (p=0.006). The rate of correct answer was higher for right hemithorax sequences (p=0.001). Accuracy in lung sliding identification is better when participants have the possibility to abstain themselves from answering in uncertain cases. It is also improved in the right hemithorax, probably owing to the presence of the heart and the lung pulse artefact in the left hemithorax. Considering our results, caution should be taken when using short ultrasound sequences for identifying lung sliding as a mean of confirming endotracheal intubation, particularly in the left hemithorax. Emphasis should also be put on knowledge and identification of the Lung pulse artefact when teaching chest ultrasound curriculum.
376

Pathophysiology and treatment of chlorine gas-induced lung injury : an experimental study in pigs /

Wang, Jianpu. January 2004 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2004. / Härtill 5 uppsatser.
377

Lung-segmentering : Förbehandling av medicinsk data vid predicering med konvolutionella neurala nätverk / Lung-segmentation : A pre-processing technique for medical data when predicting with convolutional neural networks

Gustavsson, Robin, Jakobsson, Johan January 2018 (has links)
Svenska socialstyrelsen presenterade år 2017 att lungcancer är den vanligaste cancerrelaterade dödsorsaken bland kvinnor i Sverige och den näst vanligaste bland män. Ett sätt att ta reda på om en patient har lungcancer är att en läkare studerar en tredimensionell-röntgenbild av en patients lungor. För att förebygga misstag som kan orsakas av den mänskliga faktorn är det möjligt att använda datorer och avancerade algoritmer för att upptäcka lungcancer. En nätverksmodell kan tränas att upptäcka detaljer och avvikelser i en lungröntgenbild, denna teknik kallas deep structural learning. Det är både tidskrävande och avancerat att skapa en sådan modell, det är därför viktigt att modellen tränas korrekt. Det finns flera studier som behandlar olika nätverksarkitekturer, däremot inte vad förbehandlingstekniken lung-segmentering kan ha för inverkan på en modell av denna signifikans. Därför ställde vi frågan: hur påverkas accuracy och loss hos en konvolutionell nätverksmodell när lung-segmentering appliceras på modellens tränings- och testdata? För att besvara frågan skapade vi flera modeller som använt, respektive, inte använt lung-segmentering. Modellernas resultat evaluerades och jämfördes, tekniken visade sig motverka överträning. Vi anser att denna studie kan underlätta för framtida forskning inom samma och liknande problemområde. / In the year of 2017 the Swedish social office reported the most common cancer related death amongst women was lung cancer and the second most common amongst men. A way to find out if a patient has lung cancer is for a doctor to study a computed tomography scan of a patients lungs. This introduces the chance for human error and could lead to fatal consequences. To prevent mistakes from happening it is possible to use computers and advanced algorithms for training a network model to detect details and deviations in the scans. This technique is called deep structural learning. It is both time consuming and highly challenging to create such a model. This discloses the importance of decorous training, and a lot of studies cover this subject. What these studies fail to emphasize is the significance of the preprocessing technique called lung segmentation. Therefore we investigated how is the accuracy and loss of a convolutional network model affected when lung segmentation is applied to the model’s training and test data? In this study a number of models were trained and evaluated on data where lung segmentation was applied, in relation to when it was not. The final conclusion of this report shows that the technique counteracts overfitting of a model and we allege that this study can ease further research within the same area of study.
378

L’utilisation de l’échographie pulmonaire dans la prise en charge des patients de soins critiques

Piette, Éric 05 1900 (has links)
En démontrant sa capacité d’identifier les pneumothorax, de différencier les différentes causes d’insuffisance respiratoire chez les patients dyspnéiques et de confirmer la position d’un tube endotrachéal lors d’une intubation endotrachéale, l’échographie pulmonaire a pris une place prépondérante dans la prise en charge des patients de soins critiques. La majorité des études, notamment celles sur l’intubation endotrachéale, ont évalué la performance de cliniciens possédant une expérience considérable en échographie pulmonaire et souvent dans un cadre idéal permettant des examens d’une durée prolongée. Considérant la disponibilité grandissante de l’échographie ciblée lors des situations de stabilisation et de réanimation des patients de soins critiques, nous voulions évaluer la capacité d’un groupe de clinicien hétérogène en termes de formation échographique à identifier la présence ou l’absence de glissement pleural sur de courtes séquences (comparable à la durée probable d’un examen lors de condition de réanimation) d’échographie pulmonaire enregistrées chez des patients intubés. Un total de 280 courtes séquences (entre 4 et 7 secondes) d’échographie pulmonaire démontrant la présence ou l’absence de glissement pleural chez des patients intubés en salle d’opération ont été enregistrées puis présentées de façon aléatoire à deux groupes de cliniciens en médecine d’urgence. Le deuxième groupe avait la possibilité de s’abstenir advenant une incertitude de leur réponse. Nous avons comparé la performance selon le niveau de formation académique et échographique. Le taux moyen d’identification adéquate de la présence ou l’absence du glissement pleural par participant était de 67,5% (IC 95% : 65,7-69,4) dans le premier groupe et 73,1% (IC 95% : 70,7-75,5) dans le second (p<0,001). Le taux médian de réponse adéquate pour chacune des 280 séquences était de 74,0% (EIQ : 48,0-90,0) dans le premier groupe et 83,7% (EIQ : 53,3-96,2) dans le deuxième (p=0,006). Le taux d’identification adéquate de la présence ou absence d’un glissement pleural par les participants des deux groupes était nettement supérieur pour les séquences de l’hémithorax droit par rapport à celles de l’hémithorax gauche (p=0,001). Lorsque des médecins de formation académique et échographique variable utilisent de courtes séquences d’échographie pulmonaire (plus représentatives de l’utilisation réelle en clinique), le taux d’identification adéquate de la présence ou l’absence de glissement pleural est plus élevé lorsque les participants ont la possibilité de s’abstenir en cas de doute quant à leur réponse. Le taux de bonnes réponses est également plus élevé pour les séquences de l’hémithorax droit, probablement dû à la présence sous-jacente du cœur à gauche, la plus petite taille du poumon gauche et l’effet accru du pouls pulmonaire dans l’hémithorax gauche. Considérant ces trouvailles, la prudence est de mise lors de l’utilisation de l’identification du glissement pleural sur de courtes séquences échographique comme méthode de vérification de la position d’un tube endotrachéal lors d’une intubation endotrachéale, et ce, particulièrement pour l’hémithorax gauche. Aussi, une attention particulière devrait être mise sur la reconnaissance du pouls pulmonaire lors de l’enseignement de l’échographie pulmonaire. / The field of targeted lung ultrasound in critical care is in constant expansion. Its many proven use include pneumothorax diagnosis, differentiation of the different causes of acute dyspnoea and endotracheal intubation confirmation. These studies on endotracheal intubation evaluated sonographers with extensive ultrasound training using sometimes lengthy exam. Hence, with the growing presence of bedside lung ultrasound we devised a study to evaluate the capacity of a heterogeneous group of physicians, with different levels of ultrasound training, to correctly identify lung sliding on random short sequences of recorded thoracic ultrasound. 280 short ultrasound sequences (4 to 7 seconds) of present and absent lung sliding of intubated patients recorded in the operating room were randomly presented to 2 groups of physicians. Descriptive data, mean accuracy of each participant, as well as the rate of correct answers for each of the sequences was measured and compared for different subgroups. Participants in the second group where instructed that they could abstain from answering in uncertain cases. Mean accuracy was 67.5% (95%CI: 65.7-69.4) in the first group and 73.1% (95%CI: 70.7-75.5) in the second (p<0.001). When considering each sequence individually, median accuracy was 74.0% (IQR: 48.0-90.0) in the first group and 83.7% (IQR: 53.3-96.2) in the second (p=0.006). The rate of correct answer was higher for right hemithorax sequences (p=0.001). Accuracy in lung sliding identification is better when participants have the possibility to abstain themselves from answering in uncertain cases. It is also improved in the right hemithorax, probably owing to the presence of the heart and the lung pulse artefact in the left hemithorax. Considering our results, caution should be taken when using short ultrasound sequences for identifying lung sliding as a mean of confirming endotracheal intubation, particularly in the left hemithorax. Emphasis should also be put on knowledge and identification of the Lung pulse artefact when teaching chest ultrasound curriculum.
379

Evaluating the Role of Heterogenous Mechanical Forces on Lung Cancer Development and Screening

Cho, YouJin 07 October 2021 (has links)
No description available.
380

Regulation of ERK3 by KRAS signalling and its role in the growth of lung adenocarcinoma (LUAD) cells

Akunapuram, Shreya 09 August 2023 (has links)
No description available.

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