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Mcleod, C. N. "Measurement of the nutritional intake of breast-fed babies." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382665.
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Yacoub, Chahed. "Measurement of absorbed dose to the skin and its relation with microcircular changes in breast cancer radiotherapy." Thesis, Stockholms universitet, Fysikum, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-132140.
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Radiation therapy has been shown to increase local and regional control as well as overall survival with breast cancer, but the vast majority of patients develop acute skin reactions, which are in part related to microvascular changes. These reactions vary between different skin sites. The aim of this work is to determine the absorbed dose to the skin by measurements and investigate if there is a correlation between the absorbed dose at different areas of the breast and the local changes in microcirculation in the skin after breast cancer radiotherapy. The study includes characterisation of the Gafchromic EBT3 film and Epson Perfection V600 Photo scanner which are used for absorbed dose determination. The measurements were done both on an anthropomorphic female phantom and on a patient undergoing breastcancer radiotherapy. Twenty-one pieces of film (2x1 cm2) were placed on the surface ofthe breast (both for the phantom and patient) and irradiated with a prescribed dose to the target of 2.66 Gy with two opposed fields using 6 MV beam. It was observed that mainly 45-64 % of the prescribed dose was deposited at the surface, both for the phantom and patient. Using laser speckle contrast imaging and polarised light spectroscopy, the regional changes in mean blood perfusion and in mean red blood cell concentration (RBCC) at the end of the treatment with a total prescribed dose of 42.6 Gy, compared to baseline, were measured in both the treated and untreated breast of the same patient. Although marked increases in perfusion were seen in different areas of the treated breast, there was no signicant correlation between the changes in perfusion and the absorbed dose at these areas. However, a statistical correlation was found between the changes in RBCC and the absorbed skin dose at the same areas. To further elucidate the relation between the changes in skin microcirculation and the absorbed radiation dose during breast cancer radiotherapy, future studies using a larger number of patients are needed.
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Furrer, Daniela. "The human epidermal growth factor receptor 2 (HER2) in the breast cancer : from measurement to targeted treatment." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/37361.
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La surexpression du récepteur 2 du facteur de croissance épidermique humain (HER2) et/ou l’amplification du gène HER2 sont des facteurs prédictifs du cancer du sein. Avec l’introduction du traitement ciblé au trastuzumab, l’évaluation fiable d’HER2 est devenue essentielle. Malheureusement, jusqu’à 50% des patientes HER2-positives développent une résistance envers ce médicament. Les objectifs étaient : 1) déterminer la façon la plus fiable et économique pour évaluer le statut HER2 (cohorte de 521 cas consécutifs de cancer du sein); 2) examiner l’association entre deux polymorphismes d’HER2 (Ile655Val et Ala1170Pro), la consommation de tabac et d’alcool et la réponse au trastuzumab (cohorte de 236 patientes HER2-positives traitées au trastuzumab). De plus, dans une étude pilote, nous avons examiné l’association entre les patrons de méthylation d’ADN dans la tumeur et la réponse au trastuzumab (cohorte de 12 patientes HER2-positives traitées au trastuzumab). Le statut HER2 a été évalué par immunohistochimie (IHC), hybridation fluorescente in situ (FISH) et essai TaqMan. Nous avons comparé le statut HER2 déterminé par FISH sur lame complète (LC, un tissu par lame) et par matrice tissulaire (TMA, 60 tissus par lame), ainsi que le statut HER2 évalué par IHC et FISH sur le bloc ayant servi pour le diagnostic (bloc diagnostique) et sur un bloc choisi aléatoirement (bloc aléatoire). Les informations cliniques ont été obtenues dans les dossiers médicaux, celles sur la consommation de tabac et d’alcool par des questionnaires validés. Le patron de méthylation d’ADN a été évalué en utilisant la micropuce Illumina Infinium HumanMethylation450 BeadChip. La concordance générale entre le statut HER2 déterminé par FISH sur LC et TMA était de 98,2%, et celle entre les blocs diagnostiques et aléatoires était de 98,0% au FISH et de 93,6% à l’IHC. La consommation de tabac et l’allèle Val étaient associés à une moins bonne réponse, tandis que la consommation d’alcool était associée à une meilleure réponse. Le patron de méthylation dans les tumeurs de patientes atteintes d’un cancer du sein HER2- positif qui ont développé une résistance au trastuzumab diffère de celui des patientes qui répondent au traitement. Cependant, ces résultats semblent dépendre de la méthode bioinformatique d’analyse utilisée. Nous concluons que l’évaluation d’HER2 par FISH sur TMA représente une méthode fiable et économique. Les taux de concordances obtenus par FISH, mais pas ceux observés à l’IHC, satisfont l’exigence du Collège des pathologistes américains d’au moins 95% de concordance entre les résultats obtenus avec la méthode de référence et la nouvelle méthode. Le tabagisme, la consommation d’alcool et le polymorphisme HER2 Ile655Val pourraient influencer la réponse au traitement au trastuzumab.The overexpression of the human epidermal growth factor receptor 2 (HER2) and/or HER2 gene amplification are predictive factors in breast cancer. Following the HER2-targeted treatment with trastuzumab, the reliable evaluation of HER2 has become essential. Unfortunately, up to 50% of HER2-positive breast cancer patients develop resistance towards this drug. The objectives were: 1). To determine the most reliable and economical method to evaluate HER2 status (cohort of 521 consecutive breast cancer cases); 2). To examine the association between tobacco and alcohol consumption, and two HER2 polymorphisms (Ile655Val and Ala1170Pro), and the response to trastuzumab (cohort of 236 HER2-positive breast cancer patients treated with trastuzumab). Moreover, in a pilot study, we explored the association between genome-wide DNA methylation patterns in breast cancer tissues and the response to trastuzumab (cohort of 12 breast cancer patients treated with trastuzumab). HER2 status was evaluated by immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and TaqMan assay. We compared HER2 status determined by FISH on whole tissue (WT, one tissue per slide) section and tissue microarray (TMA, 60 tissues per slide) section, and HER2 status evaluated by IHC and FISH on the block used for diagnostic (diagnostic block) and on a randomly chosen additional block (random block). Clinicopathological information were assessed by review of medical records, tobacco and alcohol consumption by an administered validated questionnaire. DNA methylation patterns were evaluated using the Illumina Infinium HumanMethylation450 BeadChip. Overall concordance between HER2 status determined by FISH on WT and TMA sections was 98.2% and that between diagnostic and random blocks was 98.0% for FISH and 93.6% for IHC. Tobacco consumption and the Val allele were associated with a worse response, whereas alcohol consumption was associated with a better response. Methylation pattern in tumor tissues of HER2-positive breast cancer patients who acquired resistance to trastuzumab treatment differed from that of HER2-positive breast cancer patients who responded to trastuzumab treatment. However, this observation seemed to depend upon the method of bioinformatics analysis used. We conclude that FISH performed on TMA section represents a reliable and economical method for the evaluation of HER2. Results obtained by FISH, but not those obtained by IHC, fulfill the recommendations of the College of American Pathologists of concordance greater than 95% between the reference method and the new method. Tobacco use, alcohol consumption and Ile655Val HER2 polymorphism might influence the response to trastuzumab treatment.
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Lagerros, Ylva Trolle. "Physical activity from the epidemiological perspective - measurement issues and health effects /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-681-6/.
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Henderson, Elizabeth. "Measurement of blood flow, blood volume and capillary permeability in breast tumours using contrast-enhanced magnetic resonance imaging." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0020/NQ58134.pdf.
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Johnson-Kozlow, Marilyn Fay. "Validity and measurement bias in three self-report measures of physical activity among women diagnosed with breast cancer /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2003. http://wwwlib.umi.com/cr/ucsd/fullcit?p3099928.
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Assi, Valentina. "Clinical and epidemiological issues and applications of mammographic density." Thesis, Queen Mary, University of London, 2014. http://qmro.qmul.ac.uk/xmlui/handle/123456789/7855.
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Mammographic density, the amount of radiodense tissue on a mammogram, is a strong risk factor for breast cancer, with properties that could be an asset in screening and prevention programmes. Its use in risk prediction contexts is currently limited, however, mainly due to di culties in measuring and interpreting density. This research investigates rstly, the properties of density as an independent marker of breast cancer risk and secondly, how density should be measured. The rst question was addressed by analysing data from a chemoprevention trial, a trial of hormonal treatment, and a cohort study of women with a family history of breast cancer . Tamoxifen-induced density reduction was observed to be a good predictor of breast cancer risk reduction in high-risk una ected subjects. Density and its changes did not predict risk or treatment outcome in subjects with a primary invasive breast tumour. Finally absolute density predicted risk better than percent density and showed a potential to improve existing risk-prediction models, even in a population at enhanced familial risk of breast cancer. The second part of thesis focuses on density measurement and in particular evaluates two fully-automated volumetric methods, Quantra and Volpara. These two methods are highly correlated and in both cases absolute density (cm3) discriminated cases from controls better than percent density. Finally, we evaluated and compared di erent measurement methods. Our ndings suggested good reliability of the Cumulus and visual assessments. Quantra volumetric estimates appeared negligibly a ected by measurement error, but were less variable than visual bi-dimensional ones, a ecting their ability to discriminate cases from controls. Overall, visual assessments showed the strongest association with breast cancer risk in comparison to computerised methods. Our research supports the hypothesis that density should have a role in personalising screening programs and risk management. Volumetric density measuring methods, though promising, could be improved.
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Soares, Christina Guimarães Ribeiro. "Etiologia e frequência da dor relatada por mulheres com câncer de mama." Universidade Federal de Sergipe, 2013. https://ri.ufs.br/handle/riufs/3685.
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Introduction: Breast cancer is the most common cancer among women and the manifestation of pain is frequent and can occur at all stages of the disease, as well as being a consequence of various diagnostics and therapeutics approaches. Objectives: To describe if the pain is related or unrelated to breast cancer, identifying the occurrence of pain in the last 24 hours, check the intensity related or unrelated to breast cancer and report the main anatomical sites of pain. Methods: A descriptive study involving outpatient women diagnosed with breast cancer at any stage of the disease or treatment, from November 2011 to April 2012. The interviews were conducted with the oncology outpatients from Hospital João Alves Filho using a screening questionnaire elaborated by the researchers and the Brief Pain Inventory (BPI). Results: Ninety women aged 27-80 years old were interviewed, 59 (66%) did not relate the pain with breast cancer and 73 (81%) reported no pain before the illness. Only 34 women (38%) reported pain in the last 24 hours negatively affect the ability to walk, sleep and mood. The average pain on a scale from 0 to 10 was 4.8. The major anatomical sites of pain were the upper extremities (23%), lower limbs (21%) and spine (15%). Conclusion: Fifty nine (56%) of the women interviewed did not relate the pain with breast cancer, highlighting the upper extremities as major anatomical sites of pain. The pain was present, in the last 24 hours, in 38% of women, in mild intensity and interfering with quality of life.Introdução: O câncer de mama é a neoplasia mais comum entre as mulheres e a manifestação de dor é um evento frequente, podendo ocorrer em todas as fases da doença, bem como ser decorrente de várias abordagens diagnósticas e terapêuticas. Objetivos: Descrever se a dor está ou não relacionada com o câncer de mama, identificar a ocorrência de dor nas últimas 24 horas, verificar a intensidade da dor relacionada ou não ao câncer e descrever os principais sítios anatômicos de dor. Casuística e método: Estudo descritivo envolvendo mulheres com diagnóstico de câncer de mama e em tratamento ambulatorial, em qualquer fase da doença ou tratamento, no período de novembro de 2011 a abril de 2012. As entrevistas foram realizadas no ambulatório de oncologia do Hospital Governador João Alves Filho, utilizando um formulário elaborado pelos pesquisadores e o Inventário Breve da Dor (IBD). Resultados: Noventa mulheres com idade entre 27 a 80 anos foram entrevistadas, 59 (66%) não relacionaram a dor com o câncer de mama e 73 (81%) não relataram a presença de dor antes da doença. Apenas 34 mulheres (38%) referiram dor nas últimas 24 horas interferindo negativamente na habilidade de caminhar, no sono e no humor. A média de dor em uma escala de 0 a 10 foi de 4,8 e os principais sítios anatômicos de dor foram os membros superiores (23%), membros inferiores (21%) e coluna vertebral (15%). Conclusão: Em 59 (66%) mulheres a dor não esteve relacionada com o câncer de mama e os MMSS foram apontados como os principais sítios anatômicos de dor. A dor esteve presente, nas últimas 24 horas, em 38% das mulheres, de intensidade moderada e interferindo na qualidade de vida.
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Griffiths, Jennifer Ann. "X-ray diffraction measurements for breast tissue analysis." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1444776/.
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Biological tissues exhibit elastic x-ray scatter properties unique to individual tissue types. It has been suggested that these properties could be exploited in the discrimination of tissues in diagnostic radiology, particularly in mammographic imaging. The work in this thesis investigates the elastic scatter from human breast tissues with a view to moving the Diffraction Enhanced Breast Imaging (DEBI) technique towards the clinical domain. Instrumentation was considered in terms of a suitable scatter detector and its associated collimation. A phosphor coated low-light-level CCD in conjunction with a parallel hole array collimator was introduced as a possible angular dispersive diffraction detector, and conically collimated HPGe was found to be a suitable detector for energy dispersive diffraction. Diffraction imaging was achieved using both planar and tomographic imaging techniques. The planar imaging considered the spatial resolution needed for clinically useful results and showed that depth information of the order of 1 cm can easily be obtained using diffraction imaging techniques. A micro-tomographic diffraction imaging technique was used to further present knowledge of the 'scatter signatures' of human breast tissue. The tissue is naturally inhomogeneous, so precise knowledge of a sample's composition is needed in order to accurately classify its scatter signature. A total of twenty seven breast tissue samples were examined, covering a range of tissue types, with nineteen of these samples being extensively studied. The microCT produced diffraction images of the inhomogeneous tissue samples and their diffraction signatures were related to the results of conventional histopathological analysis. A correlation was observed between the predominant tissue type in a sample and the ratio of the intensity of the sample's scatter at momentum transfers of 1.1 and 1.5 nm-1. A Student's t-test performed on these results gave the probability of a null hypothesis for correlation of less than 1%.
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Sindi, Rooa. "Quantitative Measurements of Breast Density Using Magnetic Resonance Imaging." Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/86105.
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This study was conducted to investigate the optimal MRI protocols for quantitative assessment of breast density. The research involved development of a patient-specific 3D-printed breast phantom for simulation of breast tissues and quantitative analysis of breast density based on phantom experiments and patient data analysis. Results of this research highlight the importance of standardising breast MRI protocols for the evaluation of breast density, predominantly for women at an elevated risk of developing breast cancer.
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Qiu, Yihong. "Measurement and analysis of breath sounds." Thesis, University of Glasgow, 2003. http://theses.gla.ac.uk/1676/.
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Existing breath sound measurement systems and possible new methods have been critically investigated. The frequency response of each part of the measurement system has been studied. Emphasis has been placed on frequency response of acoustic sensors; especially, a method to study a diaphragm type air-coupler in contact use has been proposed. Two new methods of breath sounds measurement have been studied: laser Doppler vibrometer and mobile phones. It has been shown that these two methods can find applications in breath sounds measurement, however there are some restrictions. A reliable automatic wheeze detection algorithm based on auditory modelling has been developed. That is the human’s auditory system is modelled as a bank of band pass filters, in which the bandwidths are frequency dependent. Wheezes are treated as signals additive to normal breath sounds (masker). Thus wheeze is detectable when it is above the masking threshold. This new algorithm has been validated using simulated and real data. It is superior to previous algorithms, being more reliable to detect wheezes and less prone to mistakes. Simulation of cardiorespiratory sounds and wheeze audibility tests have been developed. Simulated breath sounds can be used as a training tool, as well as an evaluation method. These simulations have shown that, under certain circumstance, there are wheezes but they are inaudible. It is postulated that this could also happen in real measurements. It has been shown that simulated sounds with predefined characteristics can be used as an objective method to evaluate automatic algorithms. Finally, the efficiency and necessity of heart sounds reduction procedures has been investigated. Based on wavelet decomposition and selective synthesis, heart sounds can be reduced with a cost of unnatural breath sounds. Heart sound reduction is shown not to be necessary if a time-frequency representation is used, as heart sounds have a fixed pattern in the time-frequency plane.
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Franks, Peter J. "Estimation of cardiac output by a single breath method." Thesis, Loughborough University, 1985. https://dspace.lboro.ac.uk/2134/32997.
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Many attempts have been made to quantify cardiac output using both invasive and non-invasive techniques. The results have generally been poorly reproducible and comparisons of techniques have yielded highly variable values. A single breath inert gas method was used in the study, since it offers several advantages over previous methods, chiefly its speed of measurement, and the controlled manner in which it is performed. The method observes the uptake of a semi-soluble inert gas (Freon-22) with respect to an insoluble marker, and calculates cardiac output (pulmonary flow) from the slope of the semi-soluble gas.
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Hargens, Trent A. "Reliability of the double product break point measurement." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1129627.
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The double product break point (DPBP) has been shown to occur in normal and cardiac subjects with values comparable to the ventilatory threshold (VT). The purpose of this study was to evaluate the intramodal and intermodal reliability of DPBP measurements during treadmill (TM) and cycle ergometry (C) exercise and to compare the DPBP to the VT. Seventeen subjects, (eight men and nine women) ages 18-60 (31.5 ± 12.4 yrs), performed four maximal exercise tests, two utilizing a standardized ramp treadmill and two utilizing an individualized ramp cycle protocol. A minimum of 48 hours separated each test. Double product (DP) was measured every 15 seconds during each test via the Kyokko Bussan CM-4001 automated blood pressure unit. Breath by breath analysis of gas exchange measurements were performed. The DPBP and VT was determined visually by three blinded observers (acceptance criteria being at least 2 observers agreeing within 10%). There were no significant intramodal differences in the V02 at the DPBP (ml'kg'1'min 1) for the two treadmill trials (23.8 + 4.9, 23.2 ±5.0) or for the two cycle trials (21.7 +7.2, 21.7 ±6.4). There was also no significant mean intermodal difference in the V02 at the DPBP for the treadmill and cycle (24.4 + 4.4, 23.1 + 5.8). Intramodal intraclass correlations for the DPBP were 0.84 and 0.79 for the treadmill and cycle, respectively. Intermodal intraclass correlation for the DPBP was 0.85. There were significant differences between the DPBP and the VT for both the treadmill (23.3 + 4.7, 28.2 ± 5.3)and the cycle (22.1 + 7.1, 27.5 ± 10.4). Correlations for the DPBP/VT comparison were 0.43 and 0.78 for the treadmill and cycle, respectively. In conclusion, results of this study suggest that DPBP measurements are reliable both intramodally and intermodally, however due to a wide range in correlations, the results suggest that the DPBP and VT are not occurring at similar V02 values.School of Physical Education
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Godavarty, Anuradha. "Fluorescence enhanced optical tomography on breast phantoms with measurements using a gain modulated intensified CCD imaging system." Texas A&M University, 2003. http://hdl.handle.net/1969.1/2184.
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Fluorescence-enhanced optical imaging using near-infrared (NIR) light developed for in-vivo molecular targeting and reporting of cancer provides promising opportunities for diagnostic imaging. However, prior to the administration of unproven contrast agents, the benefits of fluorescence-enhanced optical imaging must be assessed in feasibility phantom studies.
A novel intensified charge-coupled device (ICCD) imaging system has been developed to perform 3-D fluorescence tomographic imaging in the frequency-domain using near-infrared contrast agents. This study is unique since it (i) employs a large tissue-mimicking phantom (~1087 cc), which is shaped and sized to resemble a female breast and part of the extended chest wall region, and (ii) enables rapid data acquisition in the frequency-domain by using a gain-modulated ICCD camera. Diagnostic 3-D fluorescence-enhanced optical tomography is demonstrated using 0.5-1 cc single and multiple targets contrasted from their surrounding by ??M concentrations of Indocyanine green (ICG) in the breast-shaped phantom (10 cm diameter), under varying conditions of target-to-background absorption contrast ratios (1:0 and 100:1) and target depths (up to 3 cm deep). Boundary surface fluorescence measurements of referenced amplitude and phase shift were used along with the coupled diffusion equation of light propagation in order to perform 3-D image reconstructions using the approximate extended Kalman filter (AEKF) algorithm, and hence differentiate the target from the background based on fluorescent optical contrast.
Detection of single and multiple targets is demonstrated under various conditions of target depths (up to 2 cm deep), absorption optical contrast ratio (1:0 and 100:1), target volumes (0.5-1 cc), and multiple targets (up to three 0.5 cc targets). The feasibility of 3-D image reconstructions from simultaneous multiple point excitation sources are presented. Preliminary lifetime imaging studies with 1:2 and 2:1 optical contrast in fluorescence lifetime of the contrast agents is also demonstrated. The specificity of the optical imager is further assessed from homogeneous phantom studies containing no fluorescently contrasted targets.
While nuclear imaging currently provides clinical diagnostic opportunities using radioactive tracers, molecular targeting of tumors using non-ionizing NIR contrast agents tomographically imaged using the frequency-domain ICCD imaging system could possibly become a new method of diagnostic imaging.
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Obeidat, Mohammad Ali. "Radiotherapy Measurements with a Deoxyribonucleic Acid Doublestrand-Break Dosimeter." Thesis, The University of Texas Health Science Center at San Antonio, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10281552.
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Many types of dosimeters are used in the clinic to measure radiation dose for therapy but none of them directly measures the biological effect of this dose. The overall purpose of this work was to develop a dosimeter that measures biological damage in the form of double-strand breaks to deoxyribonucleic acid. This dosimeter could provide a more biologically relevant measure of radiation damage than the currently utilized dosimeters. A pair of oligonucleotides was designed to fabricate this dosimeter. One is labeled with a 5’-end biotin and the other with a 5’-end 6 Fluorescein amidite (fluorescent dye excited at 495?nanometer, with a peak emission at 520 nanometer). These were designed to adhere to certain locations on the pRS316 vector and serve as the primers for polymerase chain reactions. The end product of this reaction is a 4 kilo-base pair double strands deoxyribonucleic acid fragment with biotin on one end and 6 Fluorescein amidite oligonucleotide on the other attached to streptavidin beads. The biotin end connects the double strands deoxyribonucleic acid to the streptavidin bead. These bead-connected double strands deoxyribonucleic acid were suspended in 50 microliter of phosphate-buffered saline and placed into a tube for irradiation. Following irradiation of the deoxyribonucleic acid dosimeter, we take advantage of the magnetic properties of the streptavidin bead by placing our sample microtube against a magnet. The magnetic field pulls the streptavidin beads against the side of the tube. If a double-strand-break has occurred for a double strands deoxyribonucleic acid, the fluorescein end of the double strands deoxyribonucleic acid becomes free and is no longer attached to the bead or held against the side of the microtube. The free fluorescein following a double-strand-break in double strands deoxyribonucleic acid is referred to here as supernatant. The supernatant is extracted and placed in another microtube, while the unbroken double strands deoxyribonucleic acid remain attached to the beads and stay in the microtube (Fig. 4). Those beads were re-suspended with 50 microliter of phosphate-buffered saline again (called beads), then we placed both supernatant and beads in a reader microplate and we read the fluorescence signal for both with a fluorescence reader (BioTek Synergy 2). These beads and supernatant fluorescence signals are denoted by B and S, respectively. The relative amount of supernatant fluorescence counts is proportional to the probability of a double-strand-break. The probability of double-strand-break was calculated with the following equation:
(S-BG)/(S+B-2BG) (1)
where S was the supernatant fluorescence intensity (related to the number of double strands deoxyribonucleic acid with double-strand breaks), B was the re-suspended beads fluorescence intensity (related to the number of double strands deoxyribonucleic acid without double-strand breaks), and BG was the phosphate-buffered saline fluorescence intensity (related to the background signal). There are two advantages that this type of dosimeter has over the gel separation technique. First, it is important to irradiate deoxyribonucleic acid in a solution that has similar osmolarity and ion concentrations to that in a human, such as phosphate-buffered saline. A gel dosimeter would require a transfer to gel to separate deoxyribonucleic acid, whereas our dosimeter can be separated in this solution. Currently, we use pipettes to manually perform this separation, but this step could be automated. Second, the magnetic deoxyribonucleic acid separation technique is much faster than that for gel electrophoresis. Calibration of radiotherapy equipment isn’t something that happens in national science laboratories, with only world-leading experts. This is something that happens locally at every cancer clinic, with physicists that do not have the luxury of focusing solely on this one measurement. For this reason, ease of use is critical for this type of technology. (Abstract shortened by ProQuest.)
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Nwiloh, Victor Maduabuchi. "Measurement of nerve growth factor in induced sputum and exhaled breath condensate." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001581.
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Patterson, Claire Siobhan. "Portable spectroscopy system for ultra-sensitive, real-time measurement of breath ethane." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/538/.
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This thesis describes the development, characterisation and application of a portable spectroscopy system for ultra-sensitive, real-time detection of breath ethane. In healthcare, breath ethane is a widely accepted marker of free radical-induced cell damage and may be used to indicate changes in oxidative stress. The aim was to deliver a compact instrument capable of long-term, on-site use in a clinical environment, while also retaining the high performance previously achieved by lab-based systems at the University of Glasgow. The newly developed instrument has a sensitivity of 70 parts per trillion with a 1 Hz sampling rate. The system incorporates a cryogenicallycooled lead-salt laser and uses a second derivative wavelength modulation detection scheme. A thermally-managed closed-loop refrigeration system has eliminated the need for liquid coolants. The instrument has been field-tested to ensure target performance is sustained in a range of environments, both indoor and outdoor. It has since been used in a number of pilot clinical studies, both off-site and on-site, in which breath ethane was monitored as a marker of oxidative stress. The three main clinical areas investigated were dialysis, radiotherapy and intensive care. In the intensive care study, the instrument was modified to enable automatic breath sampling of inspired and expired gases of ventilated patients. This technique proved highly successful and the instrument then remained at the Southern General hospital, where it continued to be used as part of a wider study into breath ethane in intensive care patients. The use of the new spectroscopy system has enabled ultra-sensitive, rapid analysis of a large number of breath samples. The use of the new instrument, in particular for continual breath monitoring, has enabled the detection of short-lived fluctuations in breath ethane, yielding some interesting findings in a number of pilot clinical studies. Our results suggest that breath ethane may be used as an indicator of dynamic changes in oxidative stress. Further studies will be required to determine if such monitoring is of clinical benefit. Chapter 1 gives a general introduction to spectroscopy and some background to our project. A number of spectroscopic techniques and laser sources are discussed, along with a review of previous work in ethane detection. In chapter 2 some background theory of molecular spectroscopy is given, with a more detailed discussion of the wavelength modulation technique. Chapter 3 describes in detail the development of the portable spectroscopy system. The achieved performance and factors contributing to this performance are discussed in chapter 4. The field test of the instrument is reported on in chapter 5. In chapter 6 the application of the technology to breath analysis and the current challenges in this field are discussed. Example breath ethane measurements for healthy controls are provided. The clinical pilot studies conducted using the new system in areas of dialysis, intensive care and radiotherapy are discussed in chapters 7, 8, and 9 respectively. Chapter 10 contains the thesis summary and conclusions, with suggestions for future work.
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Campbell, Diane L. "The influence of aerobic exercise on double product break point in low to moderate risk adults." Muncie, Ind. : Ball State University, 2009. http://cardinalscholar.bsu.edu/641.
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Tentner, Andrea R. (Andrea Ruth). "Quantitative measurement and modeling of the DNA damage signaling network : DNA double-strand breaks." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/61234.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biological Engineering, 2009."September 2009." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 218-229).
DNA double-strand breaks (DSB) are one of the major mediators of chemotherapy-induced cytotoxicity in tumors. Cells that experience DNA damage can initiate a DNA damage-mediated cell-cycle arrest, attempt to repair the damage and, if successful, resume the cell-cycle (arrest/repair/resume). Cells can also initiate an active cell-death program known as apoptosis. However, it is not known what "formula" a cell uses to integrate protein signaling molecule activities to determine which of these paths it will take, or what protein signaling-molecules are essential to the execution of that decision. A better understanding of how these cellular decisions are made and mediated on a molecular level is essential to the improvement of existing combination and targeted chemotherapies, and to the development of novel targeted and personalized therapies. Our goal has been to gain an understanding of how cells responding to DSB integrate protein signaling-molecule activities across distinct signaling networks to make and execute binary cell-fate decisions, under conditions relevant to tumor physiology and treatment. We created a quantitative signal-response dataset, measuring signals that widely sample the response of signaling networks activated by the induction of DSB, and the associated cellular phenotypic responses, that together reflect the dynamic cellular responses that follow the induction of DSB. We made use of mathematical modeling approaches to systematically discover signal-response relationships within the DSB-responsive protein signaling network. The structure and content of the signal-response dataset is described, and the use of mathematical modeling approaches to analyze the dataset and discover specific signal-response relationships is illustrated. As a specific example, we selected a particularly strong set of identified signal-response correlations between ERK1/2 activity and S phase cell-cycle phenotype, identified in the mathematical data analysis, to posit a causal relationship between ERK1/2 and S phase cell cycle phenotype. We translated this posited causal relationship into an experimental hypothesis and experimentally test this hypothesis. We describe the validation of an experimental hypothesis based upon model-derived signal response relationships, and demonstrate a dual role for ERK1/2 in mediating cell-cycle arrest and apoptosis following DNA damage. Directions for the extension of the signal-response dataset and mathematical modeling approaches are outlined.
by Andrea R. Tentner.
Ph.D.
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Chow, Sharron Sau Ming Medical Sciences Faculty of Medicine UNSW. "Non-invasive measurement of markers of oxidative stress in asbestos-related lung diseases and pulmonary fibrosis." Publisher:University of New South Wales. Medical Sciences, 2009. http://handle.unsw.edu.au/1959.4/43771.
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Background and objective: Asbestos can cause various pulmonary diseases including asbestosis, pleural plaques and pleural thickening. Animal and in vitro studies suggest that the toxicity of asbestos is due to the iron content of the fibres which not only generate oxidants directly, but also activate the inflammatory cells in the lung that contribute to oxidative stress. This study therefore sought to establish data in man to corroborate the animal and in vitro evidence. Exhaled breath condensate (EBC) collection is a novel, non-invasive technique to collect samples from the lung for investigating inflammatory biomarkers of lung diseases. This technique is harmless, rapid and easily repeatable which leads itself to the investigation of lung diseases such as asbestos-related diseases and pulmonary fibrosis (PF) that are otherwise difficult to study. The hypothesis tested was that oxidative and nitrosylative stress markers will be elevated in the EBC of patients with asbestos-related diseases and PF compared to normal control subjects. Methods: The study design was a cross-sectional and observational in vivo study whereby EBC was collected and fractional exhaled nitric oxide (FeNO) and carbon monoxide (eCO) were measured. EBC markers including pH, hydrogen peroxide (H2O2), total nitrogen oxides (NOx), 3-nitrotyrosine (3-NT), 8-isoprostane (8-iso), total protein and transforming growth factor-β1 (TGFβ1) were measured by microelectrode analysis, colorimetric and enzyme immunoassays. 3-NT and 8-iso were further examined by immunohistochemical techniques in samples of lung tissue. Results: Subjects with asbestosis had significantly raised levels of EBC H2O2, 8-iso, total protein and FeNO compared with healthy individuals. The same markers except H2O2, but with 3-NT and eCO were again significantly increased in those with other causes of PF, compared with control subjects. Heavy nitrotyrosine staining was found on the lung sections from patients with asbestosis and PF. Conclusions: This study confirmed that increased production of reactive oxygen and nitrogen species is associated with asbestos exposure and pulmonary fibrosis in vivo confirming animal and in vitro studies. Analysis of EBC may prove a useful non-invasive tool in exploring the basic pathophysiology of lung diseases in clinical research and may in the future be used to monitor progress in asbestosis and pulmonary fibrosis.
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Garabedian, Charles. "Influence de la texturation de surface sur la biocompatibilité des implants mammaires : approches amont et clinique." Thesis, Valenciennes, Université Polytechnique Hauts-de-France, 2019. http://www.theses.fr/2019UPHF0007.
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La première structuration de surface d’implants mammaires approuvée par l’agence sanitaire américaine Food and Drug Administration (FDA) est la texturation Biocell de l’Américain Allergan en 1987. La plupart des fabricants d’implants mammaires ont ensuite adopté des procédés permettant d’obtenir des texturations similaires pour la plupart. Un rapport de l’Agence Nationale de Sécurité du Médicament et des produits de santé (ANSM) a estimé que 85% des implants vendus en France entre 2007 et 2016 étaient texturés. En 2011, la FDA alerte sur une possible association entre les implants mammaires et une forme rare et spécifique de lymphome : le Lymphome Anaplasique à Grandes Cellules Associés aux Implants Mammaires (LAGC-AIM). Le nombre de cas de LAGC-AIM a explosé depuis 2014-2015, avec une sur-représentation de la texture Biocell dans les statistiques justifiant le retrait du marché français de ces prothèses par l’ANSM en avril 2019. Ces travaux de thèse ont pour but d’évaluer l’impact de la topographie de surface des implants mammaires sur les performances cliniques du dispositif. Premièrement, une étude comparative menée sur 3 techniques de mesure de surface, ainsi qu’une analyse statistique basée sur la décomposition multi-échelle des topographies, nous ont permis de proposer une méthodologie de mesure métrologiquement correcte prenant en compte la morphologie de surface et l’échelle et de jeter la lumière sur les faiblesses de la norme ISO relative aux implants mammaires (ISO 14607). Ensuite, une classification et une dénomination morphologiquement pertinente des texturations ont été proposées et validées par un protocole original d’analyse génétique sur tissus humains et par une analyse discriminante menée sur une large base de paramètres topographiques. Des analyses topographique et statistique similaires ont été également conduites sur prothèses retirées du corps humain (ou explant), afin de quantifier l’endommagement en fonction du type de texturation et de l’échelle. Ces études permettront au GROUPE SEBBIN de concevoir une nouvelle prothèse de forme anatomique, qui alliera à la fois accroche tissulaire et minimisation des processus d’inflammation et d’endommagementThe first breast implant surface pattern approved by the American Food and Drug Administration (FDA) is Biocell texture commercialized by the American company Allergan in 1987. Most breast implant manufacturers then adopted similar surface patterning process. A report from the Agence Nationale de Sécurité du Médicament et des produits de santé (ANSM) estimated that 85% of implants sold in France between 2007 and 2016 were textured. In 2011, the FDA warned of a possible association between breast implants and a rare and specific form of lymphoma: Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL). The number of cases of BIA-ALCL has exploded since 2014-2015, with an overrepresentation of the Biocell texture in the statistics, which justified the withdrawal of the French market of these prostheses by the ANSM in April 2019. This thesis aims to evaluate the impact of breast implant surface topography on the clinical performance of the device. Firstly, a comparative study carried out on 3 surface measurement techniques, as well as a statistical analysis based on the multi-scale decomposition of the topographies, allowed us to propose a metrologically-validated measurement methodology taking into account the surface morphology and the scale and to highlight the inconsistencies of the ISO standard related to breast implants (ISO 14607). Then, a classification and a morphologically-relevant designation of the textures were proposed and validated by an original protocol of genetic analysis on human tissues and by a discriminant analysis carried out on a large base of topographical parameters. Similar topographical and statistical analyzes were also conducted on prostheses removed from the human body (or explant) in order to quantify the damage according to the type of texture and to the scale. These studies will enable the GROUPE SEBBIN to design a new anatomically-shaped prosthesis, which will combine tissue anchoring and minimization of inflammation and damage processes
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Kannath, Arun. "Precision measurement of carbon isotope ratio in exhaled breath for the detection of Helicobacter pylori." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/68791/.
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The utility of breath trace compounds as bio-markers for various physiological conditions has long been exploited for the diagnosis of various diseases. Urea breath tests have been adopted as the gold standard for the detection of Helicobacter pylori which is a primary cause for acute gastritis and peptic ulcers. In these tests, small changes in the ratio of stable CO2 isotopomers, 13CO2 and 12CO2, present in exhaled breath are measured precisely and this is conventionally done by using an Isotope Ratio Mass Spectrometer. However, the huge cost and complexity involved in operating these instruments has restricted their widespread use. A viable and low cost alternative is offered by instruments employing non-dispersive infrared absorption techniques. The feasibility of such an instrument has been explored in this work. The instrument presented here is a two channel isotope ratiometer that performs whole band integrated absorption measurements. Detection is based on a novel feedback mech- anism whereby an imbalance in the channel absorptions causes the pathlength along one of the channels to be altered in order to bring the system back to balance. This change in ratio of pathlengths is directly related to the change in the 13CO2/12CO2 concentration. Signffcant amount of work has already been done to investigate the effects of interferences from coincident absorption bands and other spectral effects that can lead to spurious results. A comprehensive description of the overall system design, development and performance evaluation of the first prototype instrument has been presented here. This involved significant computer modeling and simulations and the results were verified experimentally. These results provided sufficient evidence to suggest the feasibility of such an instrument as a diagnostic tool. It was also concluded that some design improvements were required to circumvent issues related to pathlength variation and a list of recommendations has been provided for this purpose. On the basis of the results obtained as part of this research endeavour, it was concluded that the non-dispersive instrument design presented here can form the basis for a low cost commercial alternative for performing carbon isotope ratio breath tests.
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Xing, Yangjun. "Measurement and Visualization of Electron Transfer at the Single Molecule Level." Diss., Temple University Libraries, 2009. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/47725.
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ChemistryPh.D.
Molecular electronics based on bottom-up electronic circuit design is a potential solution to meet the continuous need to miniaturize electronic devices. The development of highly conductive molecular wires, especially for long distance charge transfer, is a major milestone in the molecular electronics roadmap. A challenge presented by single molecule conductance is to define the relative influence of the molecular "core" and the molecular "interconnects" on the observed currents. Much focus has been placed on designing conductive, conjugated molecules. However, the electrode-molecule contacts can dominate the responses of metal-molecule-metal devices. We have experimentally and theoretically probed charge transfer through single phenyleneethynylene molecules terminated with thiol and carbodithioate linkers, using STM break-junction and non-equilibrium Green's function methods. The STM break-junction method utilizes repeatedly formed circuits where one or a few molecules are trapped between two electrodes, at least one of which has nanoscale dimensions. The statistical analysis of thousands of measurements yields the conductance of single molecules. Experimental data demonstrate that the carbodithioate linker not only augments electronic coupling to the metal electrode relative to thiol, but reduces the barrier to charge injection into the phenyleneethynylene bridge. The theoretical analysis shows that sulfur hybridization provides the genesis for the order-of-magnitude increased conductance in carbodithioate-terminated systems relative to those that feature the thiol linker. Collectively, these data emphasize the promising role for carbodithioate-based connectivity in molecular electronics applications involving metallic and semi-conducting electrodes. One of the strategies for building molecular wires that can transfer charge over long distance is to incorporate metal ions into the conductive molecular core. Peptide nucleic acid (PNA) is a great candidate for this purpose. Studying the conductivity of PNA can not only contribute to a better understanding of charge transfer through biomolecules, but can also help develop better molecular wires and other building blocks of molecular electronics. We study the charge transfer of PNA molecules using the STM break-junction technique and compare with traditional macroscopic voltammetric measurements. By measuring the resistance of different PNA molecules, we hope to develop a deep understanding of how charge transport though PNA is affected by factors such as the number and type of natural and artificial bases, embedded metal ions, pH, etc. Self-assembled monolayers (SAMs) of porphyrins are of great interest due to their diverse applications, including molecular devices, nano-templates, electrocatalysis, solar cells, and photosynthesis. We combined a molecular level study of the redox reactions using electrochemical scanning tunneling microscopy (EC-STM) with a macroscopic electrochemical technique, cyclic voltammetry (CV), to study two redox active porphyrin molecules, TPyP (5,10,15,20-Tetra(4-Pyridyl)-21H,23H-Porphine) and 5, 10, 15, 20-tetrakis (4-carboxylphenyl)-21H, 23H-porphine (TCPP). We showed that the adsorbed oxidized TPyP molecules slowly change to brighter contrast, consistent with the appearance of the reduced form of TPyP, under reduction condition (0.0VSCE). The time scale of the slow reduction is in the order of tens of minutes at 0.0VSCE, but accelerates at more negative potentials. We propose that protonation and deprotonation processes play an important role in the surface redox reaction due to geometric restriction of the molecules adsorbed on the surface. EC-STM and CV experiments were performed at various pH values to investigate the mechanism of this anomalously slow redox reaction. Our results show that the increased concentration of H+ hinders the reduction of porphyrins, a feature that has not been reported preciously. This provides insight into the details of the surface redox reaction.
Temple University--Theses
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Motooka, Makoto. "Single Breath-Hold Left Ventricular Volume Measurement by 0.3-Sec Turbo Fast Low-Angle Shot MR Imaging." Kyoto University, 2001. http://hdl.handle.net/2433/150520.
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Janzon, Cornelia [Verfasser], A. M. [Akademischer Betreuer] Otto, Marion Brigitta [Akademischer Betreuer] Kiechle, and Manfred [Akademischer Betreuer] Schmitt. "Evaluation of metabolic sensor-chip measurements with MCF-7 breast cancer cells / Cornelia Janzon. Gutachter: Marion Brigitta Kiechle ; Manfred Schmitt. Betreuer: A. M. Otto." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/104928108X/34.
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Mansfield, Colin David. "An investigation into the viability of an infrared diagnostic instrument for measurement of CO2 isotope ratios in breath." Thesis, University of Southampton, 2000. https://eprints.soton.ac.uk/15497/.
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Stable CO2 isotope ratio breath tests are established as a valuable tool in diagnostic and investigative medicine, with the potential to become more prominent in the future. The instrument conventionally used to measure the very small changes involved is an Isotope Ratio Mass Spectrometer however, the expense and complexity of such an instrument severely restricts the widespread and routine use of isotopic breath tests. Hence, to realise their full potential an alternative technique is required which is reliable, insensitive to environmental and component fluctuations, uncomplicated and affordable. We present a system that satisfies these criteria using broadband, non-dispersive, ground-state absorption infrared spectroscopy. Two isotopically distinct channels are created and their basal path length ratio recorded at the condition of transmitted intensity equilibrium. The change in channel path length ratios required to restore equilibrium in the 13C-enriched breath sample is directly related to the change in 13CO2 / 12CO2 concentration ratio. The system's novelty lies in this negative feedback loop balancing the signal by means of adjusting the path length of one of the channels. There is little evidence in the literature on infrared breath measurements that the possibility of interference from coincident infrared active breath trace compounds or various spectral effects that could lead to spurious results have been adequately assessed. Therefore, prior to the construction of a prototype instrument based upon this technique the question of its validity must be addressed. Furthermore, in addition to any instrument presenting a viable alternative it should also offer better reliability, long term stability and ideally be of lower cost than other emergent infrared instruments. Significant emphasis has therefore been placed upon evaluation of possible interferents, with the intention of providing an unambiguous assurance of the measurement's validity over a range of conceivable operating conditions and establishing operating tolerances that improve reliability over other infrared techniques. Also the prospect of using this technique to perform alternative isotope ratio breath tests was explored with the feasibility of using a novel filtering technique to enable measurement of 18O12O16O / 13C16O2 being investigated further. These aims were accomplished through the thorough evaluation of literature on breath trace compound's infrared spectra and by a series of theoretical computer instrument simulations, using detailed modelling of a breath sample's CO2 spectroscopy, capable of identifying, evaluating and quantifying the risks posed to a reliable measurement of 13CO2 / 12CO2 due to various spectral effects. The breath trace compound analysis revealed that 13C16O2 / 12C16O2 ratios can confidently be measured for isotopic breath tests using an instrument based on infrared absorption, the position of C02's n3 absorption band precluding any discernible risk. From the instrument simulations it has been possible to establish operating tolerances required to avoid or limit the generation of a spurious results and determine parameters necessary for the instrument's construction. Thus, we conclude that through the merits of its design and compliance to operating tolerances established the instrument described presents a viable alternative for providing highly accurate, reliable and low cost breath tests capable of being performed outside of a laboratory environment.
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Smith, Robin. "Experimental measurements of break-up reactions to study alpha clustering in carbon-12 and beryllium-9." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7866/.
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Due to the high binding energy of the α-particle, this object can preform in heavier atomic nuclei. This work explores α-clustering in ⁹Be and ¹²C by measuring their nuclear break-up. For ⁹Be, it has been proposed that the two α-particles of the unstable ⁸Be nucleus are bound together by a covalently shared neutron. This thesis reports the observation of a state in ⁹Be at 3.8 MeV through the ⁹Be(⁴He,α)ααn reaction. By comparing its reduced width with that of a potential mirror analogue in ⁹Be, its angular momentum was shown to be J < 7/2. This is consistent with a hitherto unmeasured 3/2⁺ molecular binding configuration state. The ¹²C nucleus is thought to consist of three α-clusters and its famous Hoyle state has been shown to possess an unusually large volume. Due to its low density, this state may behave like a Bose-Einstein condensate, where the fermonic structures of the constituent α-particles are no longer important. By precisely measuring the decay of the Hoyle state into three α-particles, through the ¹²C(⁴He,α)3α reaction, an upper limit for the direct 3α decay branch of 0.047% was obtained. This lies below predictions for the decay of a condensate state, casting doubt on this interpretation.
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Schmitz, Silke. "Validation of the 13C-sodium-acetate breath test for the measurement of gastric emptying in dogs in comparison to 99mtechnetium radioscintigraphy." Giessen : VVB Laufersweiler, 2007. http://d-nb.info/987990012/04.
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Nwaboh, Javis Anyangwe [Verfasser], and Karl-Heinz [Akademischer Betreuer] Gericke. "Absolute Laser Spectrometric Amount Fraction Measurements: Impact to Traceable Breath Gas Analysis / Javis Anyangwe Nwaboh ; Betreuer: Karl-Heinz Gericke." Braunschweig : Technische Universität Braunschweig, 2011. http://d-nb.info/1175825077/34.
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Beudin, Alexis. "Dynamique et échanges sédimentaires en rade de Brest impactés par l'invasion de crépidules." Thesis, Brest, 2014. http://www.theses.fr/2014BRES0045/document.
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Cette thèse est une contribution à l’étude de la dynamique sédimentaire dans l’écosystème de la rade de Brest. Elle a pour objectif de décrire, par la simulation numérique et l’observation in situ, le mouvement des masses d’eau et de sédiments sous l’influence de la marée à l’échelle de la rade, et l’impact de la distribution spatiale actuelle des populations de crépidules sur le transport de sédiments en suspension et l’évolution des fonds. Un modèle bidimensionnel horizontal (2DH) est mis en œuvre à partir du code TELEMAC. Il intègre la variabilité spatiale du substrat, et rend compte de la présence physique (macro-rugosité, partition de la contrainte de cisaillement) et de l’activité biologique (filtration de l’eau chargée de particules en suspension, production de biodépôts) des crépidules. Les mesures de hauteur d’eau, de vitesse du courant, et de vitesse de frottement valident de façon satisfaisante les choix de paramétrisation du modèle hydrodynamique. Les mesures de concentration de matière en suspension en rade de Brest sont sporadiques, et leur analyse est compliquée. Le modèle sédimentaire constitue un outil de compréhension. Il informe de l’évolution temporelle de la contribution de différents types de sédiments et de leur origine aux concentrations locales de sédiments en suspension et déposés. Il permet de suivre le cheminement des sédiments principalement en suspension, de quantifier les échanges entre les sous-bassins de la rade et avec le fond. L’introduction sur le fond des colonies de crépidules, sous forme de chaînes assimilées à des cylindres, induit une diminution de la vitesse du courant à l’aplomb et dans leur sillage, compensée par une augmentation en périphérie, entraînant une modification globale des zones d’érosion et de dépôt de sédiments. Localement, les macro-rugosités ont un effet antagoniste selon leur répartition: des densités moyennes augmentent le frottement de peau et les remises en suspension, tandis que des densités élevées induisent un masquage des sédiments sur le fond duquel résulte une accrétion. Par comparaison à leur impact hydrodynamique, l’activité biologique des crépidules joue un rôle secondaire sur la dynamique sédimentaireThis thesis is a contribution to the study of sediment dynamic in the ecosystem of the bay of Brest. It aims at describing, by numerical simulations and field observations, the movement of water and sediments in the bay under tidal forcing, and the impact of the present spatial distribution of slipper limpets on suspended sediment transport and bed evolution. A two-dimensional horizontal (2DH) model is implemented based on the TELEMAC numerical system. It integrates the spatial variability of bed sediments, accounts for the physical presence (macro-roughness, form drag - skin friction partitioning) and biological activity (filtration of water carrying suspended particles, production of biodeposit) of slipper limpets. Measurements of water level, mean flow velocity, and friction velocity satisfactorily validate the choice of parameters in the hydrodynamic model. Measurements of suspended matter concentration in the bay of Brest are sporadic, and their analysis complicated. The sediment model stands as a tool for better understanding sedimentary processes. It informs the temporal evolution of the contribution of different types of sediment, and their origin, to local suspended and deposited sediment concentrations. It allows to follow the paths of sediment transport predominantly in suspension, and to quantify the exchanges of sediments between the sub-basins of the bay and with the bed. The introduction of slipper limpet colonies on the bed, in the form of chains assimilated as cylinders, induces decreasing flow velocity above and in their wake, compensated by increasing flow velocity on the outskirts, which globally modify the patterns of sediment erosion and deposition in the bay. Locally, the macro-roughness elements have an antagonist effect depending on their distribution: medium densities increase skin friction and erosion flux, whereas high densities shelter bed sediments from which results accretion. By comparison to their hydrodynamic impact, the biological activity plays a secondary role on sediment dynamic
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Schmitz, Silke [Verfasser]. "Validation of the 13C-sodium-acetate breath test for the measurement of gastric emptying in dogs in comparison to 99mtechnetium radioscintigraphy / eingereicht von Silke Schmitz." Giessen : VVB Laufersweiler, 2007. http://d-nb.info/988756749/34.
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Tentner, Andrea R. (Andrea Ruth). "A novel high-throughput in-cell Western assay for the quantitative measurement of signaling dynamics in DNA damage signaling networks : cell decision processes in response to DNA double strand breaks." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34561.
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Thesis (S.M.)--Massachusetts Institute of Technology, Biological Engineering Division, June 2006."February 2006."
Includes bibliographical references (leaves 56-59).
Following exposure to DNA damage, cells initiate a stress response involving multiple protein kinase signaling cascades. The DNA damage response results in one of several possible cell-fate decisions, or cellular responses: induction of cell-cycle arrest, initiation of DNA repair, activation of transcriptional programs, and either apoptosis, necrosis or cell senescence. The mechanisms by which cells make these decisions, and how cell fate depends upon variables such as DNA damage type and dose, and other environmental factors, is unknown. The process by which cells select among alternate fates following such stimuli, or "cues" is likely to involve a dynamic, multi-variate integration of signals from each of the kinase signaling components. A major goal of signal transduction research is to understand how information flows through signal transduction pathways downstream of a given cue, such as DNA damage, and how signals are integrated, in order to mediate cellular responses. Mathematical modeling approaches are necessary to advance our understanding of these processes.
(cont.) Indeed, statistical mining and modeling of large datasets, consisting of quantitative, dynamic signaling and response measurements, is capable of yielding models that identify key signaling components in a given cue-response relationship, as well as models that are highly predictive of cellular response following novel cues that perturb the same network. We have validated a novel assay system that allows for the high throughput collection of quantitative and dynamic signaling data for 7 protein kinases or phospho-proteins known to be "hubs" in the DNA damage response and/or general stress response networks, including ATM, Chk2, H2AX, JNK, p38, ERK and p53. This novel high-throughput In-cell Western assay is based on immuno-fluorescent staining and detection of target proteins in a "whole cell" environment, performed and visualized in a 96-well plate format. This assay allows for the detection and measurement of up to 7 target proteins in triplicate, over up to 3 treatment regimes, or up to 21 signals for a single treatment, simultaneously. Pre-processing steps, and steps involved in the protocol itself are significantly fewer (and require smaller amount of most reagents and biological material),
(cont.) as compared to traditional signal measurement methods, such as quantitative Western analysis and kinase assays. We have used this novel high-throughput In-cell Western assay to investigate the DNA damage response after the specific induction of DNA double strand breaks (DSB). We have measured the dynamics of seven "hub" proteins modified with activating phosphorylations (as a surrogate measure of protein activity) that span major branches of the DNA damage, stress, and death signaling networks, following the specific induction of DNA double strand breaks. Signaling proteins measured include ATM, Chk2, H2AX, JNK, p38, ERK and p53. In parallel with these signaling measurements, we have quantitatively measured corresponding phenotypic responses, such as cell cycle profile and apoptosis. In future work, we will use a Partial Least Squares (PLS) regression analysis approach to construct a statistical model using this data, which is predictive of the cellular responses included in our measurements, following perturbation of this branch of the DNA damage response network. This analysis should reveal key signaling components involved in the decision-making process (possible molecular targets for the improvement of cancer therapy regimens that rely upon the induction of DSB, e.g. the topoisomerase inhibitor, cisplatin), and provide a basis for constructing new, and improving existing, physics-chemical models of this branch of the DNA damage response network.
by Andrea R. Tentner.
S.M.
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Javedan, Khosrow. "Investigation of Buildup Dose for Therapeutic Intensity Modulated Photon Beams in Radiation Therapy." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3449.
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Buildup dose of Mega Voltage (MV) photon beams can be a limiting factor in intensitymodulated radiation therapy (IMRT) treatments. Excessive doses can cause patient discomfort and treatment interruptions, while underdosing may lead to local failure.
Many factors which contribute to buildup dose, including the photon beam energy spectrum, scattered or contaminant radiation and their angular distribution, are not modeled well in commercial treatment planning systems. The accurate Monte Carlo method was employed in the studies to estimate the doses.
Buildup dose of 6MV photon beams was investigated for three fundamentally different IMRT modalities: between Helical TomoTherapy and traditional opposed tangential beams, solid IMRT and multileaf collimator (MLC)-based IMRT techniques. Solid IMRT, as an alternative to MLC, achieves prescription dose distribution objectives, according to our study.
Measurements and Monte Carlo calculations of buildup dose in chest wall treatment were compared between TomoTherapy IMRT and traditional tangential-beam technique. The effect of bolus in helical delivery was also investigated in this study.
In addition, measurements and Monte Carlo calculations of buildup dose in solid IMRT and MLC based IMRT treatment modalities were compared. A brass step compensator was designed and built for the solid IMRT. Matching MLC step sequences were used for the MLC IMRT.
This dissertation also presents the commissioning of a Monte Carlo code system, BEAMnrc, for a Varian Trilogy linear accelerator (LINAC) and the application in buildup dose calculation. Scattered dose components, MLC component dose and mean spectral energy for the IMRT treatment techniques were analyzed.
The agreement between measured 6MV and calculated depth dose and beam profiles was (± 1% or ±1 mm) for 10x10 and 40x40 cm2 fields. The optimum electron beam energy and its radial distribution incident on tungsten target were found to be 6 MeV and 1 mm respectively.
The helical delivery study concluded that buildup dose is higher with TomoTherapy compared to the opposed tangential technique in chest wall treatment. The solid and MLC IMRT comparison concluded that buildup dose was up to 7% lower for solid IMRT compared to MLC IMRT due to beam hardening of brass.
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Rudolf, Ladislav. "Použití bezkartáčového stejnosměrného motoru pro pohon lineárního servopohonu s bezpečnostní funkcí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219451.
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In this work, a proposal for BLDC motor control, which will be used as a drive linear actuator. Control with microcontroller focuses mainly aspects such as motor mode, regenerative mode, measuring rotor position sensors and measuring the motor current, which corresponds to the moment. The result of the work is focused on upgrading the existing Honeywell actuator, where the processor-controlled BLDC motor to replace the existing system and take over the actuator working function and emergency function.
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Andrews, Caryn. "The measurement of modesty among Jewish American women /." 2004. http://wwwlib.umi.com/dissertations/fullcit/3131504.
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Zysk, Adam Michael. "Surgical breast cancer localization via coherent measurement of endogenous optical properties /." 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3270070.
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Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007.Source: Dissertation Abstracts International, Volume: 68-07, Section: B, page: 4743. Adviser: Stephen Allen Boppart. Includes bibliographical references (leaves 110-129) Available on microfilm from Pro Quest Information and Learning.
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Chen, Li-Ping, and 陳麗萍. "Surface dose measurement for breast cancer by intensity modulated radiation therapy." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/4qgnmq.
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碩士中臺科技大學
放射科學研究所
97
Abstract The radiotherapy is a common auxiliary method for breast cancer treatment. Some breast cancer patients will show the obvious skin effect in the treatment area in later period of treatment course or after accepting the treatment. In order to evaluate the surface dose in the skin area when patient accepts the intensity modulation radiation therapy for breast cancer treatment. In this study, we measured surface dose with the Gafchromic EBT film and with two different thickness thermoluminescent dosimeters in the Rando-Phantom. The intensity modulation radiation therapy technique in this study was delivered with 6 MV and the prescribed dose was 180 cGy. To evaluate the surface dose accurately, the Gafchromic EBT film must be calibrate with statistical method. The thermoluminescent dosimeters were calibrated and selected with statistical method. Based on statistical calibration method, we can assure the accuracy in dose measurement with Gafchromic EBT film and thermoluminescent dosimeters. In this study, we also analyzed the different results of dose measurement between Gafchromic EBT film and thermoluminescent dosimeters. The results for our study could be a valuable reference for clinical application. Keywords: Intensity Modulation Radiation Therapy, Gafchromic EBT film, thermoluminescent dosimeter, surface dose
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Chao, You-Kuan, and 趙又寬. "Quantitative Measurement of Breast Tissue on Intravoxel Incoherent Motion(IVIM) MR Image." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/rxru28.
Full textAbstract:
碩士國立中興大學
通訊工程研究所
106
Breast cancer is one of the top ten cause of death among women in the world. Breast density is positively correlated with breast cancer. In recent years, Magnetic Resonance Imaging has gradually taken the place of traditional X-ray and ultrasound detection as a tool for breast cancer screening. Using the MR image not only has no radiation problems, but also has excellent image resolution. Therefore, we developed a method for classifying breast tissue using IVIM MR images. MR images such as T1, T2, and PD were used as inputs for glandular detection. In order to closely examine the location of the glandular, we used constrained energy minimization (CEM) method to detect glandular and fat and used them as correct positions. After getting the positions of glandular and fat, we use them to map on the IVIM MR images, and then analyzing the five parameters (D, D*, ADC, PF, and slope). Parameters is including Apparent Diffusion Coefficient, different b values weighted on different signal attenuation, perfusion-related diffusion and perfusion fraction. The accumulation of parameter statistics will define the critical values of glandular and fat. Finally, when we only input MR IVIM MR images, breast tissues can be classified without using T1, T2 or PD images.
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Shen, Sih-Yu, and 沈思與. "Measurement of dose distributions for full-field digital mammography and digital breast tomosynthesis." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/40921148985971162630.
Full textAbstract:
碩士中山醫學大學
生物醫學科學學系碩士班
104
Introduction X-ray mammography is an important clinical examination for breast cancer detection. At present, full-field digital mammography and digital breast tomosynthesis are frequently used imaging techniques. The currently used breast phantoms are rigid construction and cannot be deformed during the compression procedure. In our previous study, Bolus phantom was introduced for thickness measurement and image quality assessment. The purpose of this study is the measurement of dose distributions with Bolus phantom for full-field digital mammography and digital breast tomosynthesis. Material and methods In this study, Bolus slabs were used to design the compressible phantom. Two mammography systems, Siemens Novation DR and Hologic Selenia Dimensions, were used. Total of 210 TLD-100H (LiF：Mg, Cu, P) chips and the Harshaw 3500 TLD reader were used for dose measurement. For spatial and environmental dose measurements, several TLD-100H chips were placed at the location of 90, 120 and 140 cm above the ground to simulate gonad, breast and thyroid positions, respectively. For dose assessment with Bolus phantom, backscatter factor (BSF) and depth dose were measured for target/filter combination of Mo/Mo, Mo/Rh, W/Rh, W/Ag and W/Al. TLD chips was placed on the surface and embedded in different depths of Bolus phantom (2-8 cm). These Bolus phantoms were irradiated with FFDM and DBT systems. The BSF and depth dose of Bolus phantom were calculated. AGD of Bolus phantom for each exposure was estimated. The conversion factor of AGD, defined as the ratio of AGD and measured dose at central layer of Bolus phantom, was calculated for each thickness of Bolus phantom. For clinical application, the TLD-100H chips were embedded in the central layer of Bolus phantoms (2, 4, 6, 8 cm). These Bolus phantoms were compressed with different forces (78.3, 117.4 and 156.6 N) and irradiated with auto exposure control mode. The conversion factors of AGD were applied to estimate the AGD of Bolus phantoms. Results and discussion For spatial dose distribution, the measurement doses of breast position are greater than thyroid and gonad positions. For environmental dose distribution, the range of measured doses of right and left wall was 0.828-1.650 mGy which is greater than the measured doses of anterior and posterior wall (0.001-0.408 mGy). For the BSF assessment, the BSF of Bolus phantom is ranging from 1.082 to 1.122 mGy/mGy. The BSF values of Bolus phantom obtained are comparable to those of currently used breast phantom (1.006-1.102 mGy/mGy) and are within the suggested range of the European guideline (1.07-1.13 mGy/mGy). For the depth dose of Bolus phantom, the dose measured by TLD decreased with increasing depth of Bolus phantom for both of FFDM and Tomo mode. For FFDM mode, the measured doses at the central layer were 0.51±0.01, 0.65±0.01, 0.70±0.01, 1.39±0.001, 2.02±0.04, 1.95±0.03, and 1.99±0.05 mGy for 2-, 3-, 4-, 5-, 6-, 7-, and 8-cm Bolus phantom, respectively. For Tomo mode, the measured doses at the central layer were 1.20±0.02, 1.22±0.04, 1.55±0.03, 1.78±0.001, 2.38±0.03, 3.10±0.03, and 3.63±0.02 mGy for 2-, 3-, 4-, 5-, 6-, 7-, and 8-cm Bolus phantom, respectively. For each exposure, the AGD of Bolus phantom imaging with Tomo mode was higher than AGD of Bolus phantom imaging with FFDM mode. In this study, the conversion factor of AGD increased with increasing of Bolus phantom for FFDM mode (0.89-1.18 mGy/mGy) but the conversion factor of AGD varied slightly for Tomo mode (0.78-0.90 mGy/mGy). For clinical application, the measured doses by TLD (1.24-3.09 mGy) were greater than the calculated AGD (1.06-2.93 mGy). The average prediction errors on AGD were -8±7 % and 4±12 % for flexible and rigid paddle, respectively. Conclusion For spatial and environmental dose measurement, the measured spatial doses of breast position are higher than those of thyroid and gonad positions, and the measured environmental doses of left and right directions are higher than anterior and posterior directions. In this study, the BSF of Bolus phantom is similar to those of frequently used phantom materials in mammography. Therefore, Bolus phantom is suitable for dose assessment in mammography. Applying the conversion factor of AGD purposed in this study, the AGD of Bolus phantom can be estimated by measuring the doses at central layer of Bolus phantom. In clinical application, the TLD chips did not break during the compression procedure. Therefore, the Bolus phantom combined TLD chip is suitable for the measurement of dose distribution during the clinical compression procedure in mammography.
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Megens, Antoinette Maria. "Measurement of upper extremity volume in women following axillary dissection for breast cancer." Thesis, 1999. http://hdl.handle.net/2429/9181.
Full textAbstract:
Women who have been treated for breast cancer with axillary surgery and/or
radiation are at an increased risk of developing lymphedema in the ipsilateral upper
extremity. In order to ensure accuracy in the measurement of upper extremity volume,
and thus provide appropriate treatment options for lymphedema, a reliable and valid
measurement method must be determined.
The gold standard for clinical measurement of limb volume is water displacement
volumetry, which can be time-consuming and unhygienic. The purpose of this research
project was to determine if two methods of calculated upper extremity volume (using arm
circumferences) could be substituted for measured water displacement volume in women
after treatment for breast cancer. Inter-rater and test-retest reliability of circumferential
measurements and water displacement volumetry were also examined.
The subjects were 23 women who were at risk for lymphedema, having undergone
axillary lymph node dissection surgery for breast cancer. Seventeen of the women had
additional radiation therapy. Subjects had circumference and volume measurements
taken of bilateral upper extremities by two physical therapists on the first day, and one
week later by one of the physical therapists.
Intraclass correlation coefficients (ICCs) were calculated to analyze
circumferential and volume measurement reliability. Pearson product moment
correlation coefficient (Pearson r) was used to evaluate the correlation between volumetry
measurements and calculated volumes. Limits of agreement were calculated in order to
determine the amount of agreement between the measurement methods. Upper extremities ipsilateral to the breast surgery were compared separately to contralateral
upper extremities.
Inter-rater and test-retest reliability ICCs for circumferential data were 0.99 and
0.99, for surgical upper extremities and contralateral upper extremities. Inter-rater and
test-retest reliability ICCs for volumetric data were 0.99 and 0.99, for surgical upper
extremities and contralateral upper extremities. Pearson-r values were 0.93 and 0.97 for
the single truncated cone volume calculation and the summed truncated cone volume
calculation respectively. Limits of agreement were (mean +/- 2sd) -52 +/- 334 mL, and
-40 +/- 234 mL for single truncated cone calculation and summed truncated cone
calculation respectively.
The results of this investigation suggest that calculated and volumetric
measurements in this population are both reliable and closely related, but do not agree
with each other, and thus can not be used interchangeably.
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Wang, Ting-Yin, and 王亭尹. "Measurement of image quality and radiation dose of compressible breast phantoms in mammography." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8fc6dg.
Full textAbstract:
碩士中山醫學大學
醫學影像暨放射科學系碩士班
106
Purpose At present, the rigid-type breast phantoms are frequently used for assessments of image quality and radiation dose in mammography. These breast phantoms cannot accurately simulate imaging factors, image quality, and radiation dose under clinical compression procedures in digital breast tomosynthesis (DBT). The purpose of this study is the measurement of image quality and radiation dose in DBT using compressible breast phantom. Materials and methods The DBT system (Selenia Dimensions, Hologic) was used in this study. The contrast-detail mammographic phantom (Artinis CDMAM 3.4) and the thermoluminescent dosimeter TLD-100 microcubes (Harshaw/Bicron, Solon, OH) were used for measuring image quality and radiation dose, respectively. To measure the image quality, 4-8 cm Bolus phantoms (MT-CB-410S, CIVCO, Medical Solution, France) with the CDMAM were irradiated and the CDMAM images were constructed with FFDM and SM mode. These CDMAM images were read and scored by three observers. To measure the radiation doses, 3-10 cm Bolus phantoms with 50 microcubes of TLD-100 were irradiated under FFDM and DBT modes. The TLDs were placed in the different depths of the Bolus phantoms for the assessment of depth dose distribution. In the clinical compression applications, the 4-8 cm Bolus phantoms with TLDs were compressed with forces of 58.8-156.8 N. The depth of each TLD in the Bolus phantom was investigated using the sectional image of DBT and the dose of each TLD was measured. Results In the assessment of image quality, the correction observation ratios of CDMAM images of FFDM was those of CDMAM images of SM mode. For example, the correction observation ratios of CDMAM images with the 6-cm Bolus phantom for FFDM and SM modes were 49.4% and 35.1%, respectively. In the assessment of radiation dose, the measured dose decreased with the increasing depth of TLD. For example, the measured doses of TLDs in the 6-cm Bolus phantom for FFDM and DBT modes were 0.61-5.46 and 0.92-5.55 mGy, respectively. In the clinical application, the depth of TLD decreased with the increasing compression forces. The measured doses of TLDs around the central layer were comparable to the average glandular dose (AGD) of the compressible breast phantoms. Conclusion Results from this study demonstrated that the image quality of FFDM is superior to that of SM for a compressible breast phantom with large thickness. We also observed that the impact on radiation doses caused by changing compression forces is significant for a compressible breast phantom with large thickness. Therefore, the Bolus phantoms and TLD-100 microcubes are suitable for the measurements of the image quality and radiation dose in different clinical DBT applications.
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Shih, Yih-Lih, and 施易利. "NIR Electro-optical Measurement and Analysis for the Heterogeneous Intralipid Phantoms Imitating Breast Tumors." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/08906851644095925933.
Full textAbstract:
碩士國立中央大學
機械工程研究所
94
Near infrared (NIR) diffuse optical tomography (DOT) is a new medical imaging modality, the advantages are safe (longer wavelength) and non-radioactive, in spite of its low spatial resolution at the current phase. Due to the diagnostic potential of NIR,the abnormality of tissues in NIR light is to allow earlier detection rather than most other imaging modalities. This thesis describes the NIR Electro-optical measurement for Intralipid phantoms using our own developed NIR DOT scanning instrument with highly spatially angular resolution, in order to investigate the influence of different factors such as the off-boundary, the volume density (v.d.) of inclusion, and the size ratio. The influence of each condition also can reveal the real condition of biomedical tissue, and this information can offer the doctor for diagnosis. This thesis discusses Intralipid phantoms which are the homogeneous background with one inclusion or two inclusions. For the homogeneous background with one inclusion and the source position at s0 , the contrast is large, the resolution of inclusion position is good but the resolution of inclusion size is bad. The off-boundary is small, the resolution of contrast and inclusion size are both good. The inclusion size is large, the resolution of contrast is good but the resolution of off-boundary is bad. For the homogeneous background with two inclusions and the source position at s0 , the contrast (I0) is large; the resolution of inclusion position is good. The off-boundary (I0) is small confined to the non-directly detected inclusion (I4) with small v.d.; the resolution of contrast is good. The common conclusion for the homogeneous background with one inclusion and two inclusions can be obtained. Those phenomena are similar in some condition, especially for source position at s0 and Sπ. This thesis also simulates a power curve by using an exponential form. The light trajectory of model in this thesis was set as straight line, unlike the real trajectory. The outcome does not seem well. From this thesis, it can give a general concept about the influence of different factors. Furthermore, the original experimental data can be used as the input and the calibration of image reconstruction.
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Ciou, Jian-Jhong, and 邱健忠. "Measurement and analysis for the solid breast-like phantoms by use of frequency-domain Near-infrared instrument." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/62250120555378791899.
Full textAbstract:
碩士國立中央大學
生物醫學工程研究所
100
Near-infrared diffuse optical tomography (NIR-DOT) is a new non-invasive and non-radiation biomedical imaging technique. This NIR-DOT technique uses the near-infrared light illuminating the tissue and measures the transmitted light from the tissue boundary. Using the reconstruction algorithm with the measured data, one can estimate the optical coefficients (scattering coefficients, absorption coefficients) distribution inside the tissue. This is because the optical coefficients vary with the structure and composition within the tissue. In this study, we use frequency-domain scanning system to measure the intensity and phase difference of light propagating through tissue-like phantom, and determine whether heterogeneous inclusion (lesion) appears in phantom or not by images reconstructed from measurement data. In experiment, the tissue-like phantom was made by different type of pork to simulate the optical properties of breast. In order to construct breast-like phantom with different condition of lesion, the solid breast-like phantom was also fabricated by silicone, ink, and titanium dioxide powder, according to the structure of female breast. System verification is first performed by comparing the measurement data from homogenous phantom and the predicted data from the theory model, and judging from the measurement with tissue-like phantom shows that the measurement system is able to differentiate the optical properties in tissue. Moreover, the detect-ability of measuring system is confirmed by comparing the measured data with breast-like phantom under conditions of different inclusion contrast, size, and location. Observation from 1-D optical property profile of images reconstructed from such measurement data shows that the inclusion location is more dominant factor affecting the measurement result.
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Fairbanks, E. Jefferson. "One-shot measurement of spin-lattice relaxation times in the off-resonance rotating frame of reference with applications to breast." 1994. http://catalog.hathitrust.org/api/volumes/oclc/31514001.html.
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Usha, Devi Amma C. "Ultrasound Assisted Optical Elastography For Measurement Of Mechanical Properties Of Soft Tissue Mimicking Phantoms." Thesis, 2006. http://hdl.handle.net/2005/394.
Full textAbstract:
This work describes the development of an optical probe for measuring movement of tissue particles deep inside which are loaded by an ultrasound remote palpation device. The principle of the method is that ultrasound force which can be applied inside the tissue makes the tissue particles vibrate and this vibration phase-modulates the light intercepting the insoniified region which results in a modulated speckle intensity on detection outside the object. This speckle intensity modulation detected through the measured intensity autocorrelation is a measure of the vibration amplitude. Since the vibration amplitude is related to the local elastic properties of the medium, the measured modulation depth in intensity autocorrelation can be used to map the elastic property in the insonified region. In this work, first the ultrasound induced force is calculated for both plane and focused ultrasound beams, and converted to amplitude of vibration and refractive index modulation, solving the forward elastography equation. Light propagation inside an insonified object is modelled using Monte Carlo simulation and the amplitude and intensity correlations are computed. The modulation depth on the autocorrelation is estimated and shown that it is inversely correlated to the local elastic modulus and optical absorption coefficient. It is further shown that whereas the variation in modulation depth is linear with respect to absorption coefficient, the same variation with elastic property is nonlinear. These results are verified experimentally in a tissue mimicking phantom. The phantom was constructed out of poly vinyl alcohol(PVA) whose optical, mechanical and acoustic properties are independently controlled. It is also shown that for loading with focused ultrasound beam the displacement is almost along the ultrasound transducer axis and therefore the contribution from refractive index modulation alone can be ascertained by probing the insonified perpendicular to the transducer axis. This helps one to find the contribution to the modulation depth from the ultrasound-induced vibration, which can be used to compute a quantitative estimate of the elastic modulus from the modulation depth.
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Wu, Yao-Ho, and 吳樂禾. "Technology of Human Oral Breath Humidity and Temperature Measurement." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/27bxwr.
Full textAbstract:
碩士國立中興大學
生物產業機電工程學系所
99
Gas analysis and monitoring of human respiratory is a topic which has been strived in the medicine. Lots of research and instruments are used for physical/ chemical human breathing gas measured. Excepting the expensive instruments, some portable sensors have been studied on human breathing. The human airway has the ability to warm and humidify the nearby air. The temperature and humidity of the inhaled air can be measured and served as an index for human breathing analysis. The quantifications of the changed temperature and humidity by the breath of test people were discussed in this study. The measurand were served as the personal air-conditioning index of the airway for the clinical. The sensing system of this study could be integrated with other sensors for physical/ chemical human breathing gas measuring. To ensure the correction of the measurement for the human breathing temperature and humidity, a sensing system with the traceability must be built. Then the temperature and humidity from oral breathing and the environment were measured with calibrated thermocouple and humidity sensors. These data were coupled with DAQ. Changes of temperature and humidity by human oral breathing among different physical states and sexes were analysed with statistic test. Humidity should be transferred into absolute humidity to express its meaning. According to the result, the temperatures and humidities from human oral breathing were changed with different actions. In this study, the average temperature and humidity changed by oral breathing of female samples were higher than that of the male’s.
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Pieschl, Richard Lynn. "A breath-by-breath respiratory measurement system and implementation of a functional residual capacity algorithm." 1988. http://hdl.handle.net/2097/22460.
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"Measurement of Molecular Conductance." Doctoral diss., 2011. http://hdl.handle.net/2286/R.I.9439.
Full textAbstract:
abstract: This dissertation describes the work on two projects which involves measuring molecular conductance and studying their properties on the nanoscale using various Scanning Tunneling Microscopy (STM) techniques. The first molecule studied was a porphyrin-fullerene moiety known as a molecular Dyad for photovoltaic applications. This project is further divided into two section, the first one involving the characterization of the Dyad monolayers and conductance measurement in the dark. The Dyads are designed to form charge separated states on illumination. The lifetime of the charged states have been measured efficiently but the single-molecule conductance through the molecules have yet to be characterized. The second part of the project describes the set-up of a novel sample stage which enables the study of molecular conductance under illumination. This part also describes the subsequent study of the molecule under illumination and the observation of a unique charge-separated state. It also contains the verification of the presence of this charge-separated using other characterization techniques like transient absorption spectroscopy. The second project described in the dissertation was studying and comparing the predicted rectifying nature of two molecules, identical in every way except for one stereocenter. This project describes the formation of monolayers of the molecule on gold and then studying and analyzing the current-voltage characteristics of the molecules and looking for rectification. Both the molecules proved to be rectifying, one more than the other as predicted by theoretical calculations.Dissertation/Thesis
Ph.D. Chemistry 2011
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Holland, Ben Patrick. "Measurement of exhaled nitric oxide and carbon dioxide in the breath of beef calves." 2006. http://digital.library.okstate.edu/etd/umi-okstate-1956.pdf.
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Narayana, T. S. "Measurement And Prediction Of Four-pole Parameters And Break-out Noice Of Mufflers." Thesis, 2005. http://etd.iisc.ernet.in/handle/2005/1361.
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