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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Influência da queima da palha de cana de açúcar na constituição do material particulado atmosférico (MP2,5 e MP10) e as suas implicações potenciais sobre a saúde humana

Silva, Flavio Soares [UNESP] 25 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-25Bitstream added on 2014-06-13T18:46:16Z : No. of bitstreams: 1 silva_fs_dr_araiq.pdf: 2849421 bytes, checksum: 9c4094e5d741a2f65f25f770fedc84be (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No Brasil, a queima da cana de açúcar é utilizada para facilitar a colheita, mas este procedimento causa grande poluição ambiental devido a quantidade de fuligem lançada na atmosfera. O material particulado (MP) emitido contém inúmeros contaminantes, tais como: hidrocarbonetos policíclicos aromáticos (HPAs) e elementos. A cidade de Araraquara/SP possui cerca de 200.000 habitantes e é cercada por plantações de cana de açúcar, sendo que a prática de queimada é constante no período da safra (abril-novembro, todos os anos). Neste trabalho, determinou-se a concentração elementar e de HPAs em MP na cidade de Araraquara durante o período da safra (S) e da entre safra (E) da cana de açúcar. Foram coletadas 60 amostras (E) e 220 amostras (S) para a análise de HPAs, e 10 amostras (E) e 10 amostras (S) para a análise elementar. As amostras foram coletadas utilizando um amostrador dicotômico (vazão: 10 L min-1, 24 h) com filtros de PTFE (37 mm, 2 μm de tamanho de poro). Para a análise de HPAs, dez filtros de PTFE contendo o MP foram extraídos em banho de ultrassom com acetona/n-hexano (1:1 v/v), sendo que as análises foram efetuadas por HPLC/FLD. A análise elementar foi efetuada por fluorescência de raios X por energia dispersiva (EDXRF), sem tratamento prévio das amostras. A concentração mediana de HPAs totais foi de 1,9 ng m-3 (E) e 6,2 ng m-3 (S). A concentração mediana de benzo[a]pireno, HPA considerado carcinogênico, foi de 0,026 ng m-3 e 0,15 ng m-3 para os períodos de E e S, respectivamente. O risco potencial de câncer associado à exposição a HPAs por inalação, foi estimado com base na concentração de benzo[a]pireno equivalente (BaPeq), onde a toxicidade de uma mistura de HPAs é definida pela concentração de cada substância multiplicada pelo seu fator de equivalência de toxicidade relativa (FET). Os valores medianos encontrados para... / In Brazil, the sugar cane crops are burned to facilitate the harvesting, this procedure causes environmental pollution from the large amounts of soot that are released into the atmosphere. This particulate matter (MP) contains numerous contaminants such as polycyclic aromatic hydrocarbons (PAHs) and metals. The city of Araraquara, located at central area from São Paulo State, has around 200,000 inhabitants and is surrounded by sugarcane plantations (46,994 ha of total cultivated area, in the harvest 2008/2009). In this study, PAHs concentrations and elemental composition in the MP were determined in Araraquara city during the sugarcane harvesting (HV) and non-harvesting (NHV) seasons. 60 samples were collected during the NHV and 220 samples during the HV seasons for the analysis of PAHs. 10 samples were collected during the NHV and 10 samples during the HV season for the analysis of Si, K, Ca, Ti, V, Fe, Sr, Cr, Ni, Mn, Cu, Zn, As, Cd, Pb, Sb, Al, S and Cl. The samples were collected using a dichotomous sampler (10 L min-1, 24 h) with PTFE filters. Ten filters sets were extracted (ultrasonic bath with hexane/acetone (1:1 v/v)) and analyzed by HPLC/FLD for the analysis of PAHs. Information concerning the bulk elemental concentration was provided by energy-dispersive x-ray fluorescence (EDXRF). The median concentration for total PAHs was 1.9 ng m-3 (NHV) and 6.2 ng m-3 (HV). Benzo[a]pyrene median concentration was 0.026 ng m-3 and 0.15 ng m-3 for the NHV and HV seasons, respectively. The potential cancer risk associated to inhalation exposure was estimated based on the benzo[a]pyrene toxic equivalence (BaPeq), where the overall toxicity of a PAH mixture is defined by the concentration of each compound multiplied... (Complete abstract click electronic access below)
72

The association of socioeconomic status with cervical cancer risk misperceptions, Pap smear screening adherence and cervical outcomes among Ohio Appalachian women

Bernardo, Brittany Marie January 2020 (has links)
No description available.
73

INTERCHANGEABLE SMARTPHONE TACTILE IMAGING PROBE SYSTEM AND APPLICATIONS

Choi, Sung In, 0000-0001-9255-7540 January 2023 (has links)
Many medical devices have been shifting to personal platforms such as smartphones due to its ubiquitous availability, variety of included sensors, robust communication, and user-friendliness. By utilizing smartphones as a medical sensing device should improve the early detection of abnormalities and the long-term monitoring of health conditions. Tissue abnormalities will be detected by touch sensation due to mechanical property changes within the tissue. However, touch sensation is unquantifiable and subjective. We integrate the smartphone with a tactile sensor to build a portable and personalized tissue assessment device based on changes in mechanical properties. The Smartphone Tactile Imaging Probe (STIP) is developed to quantify the mechanical properties of the tissue. The proposed system has a dual-sensing mode: compression-based sensing (STIP-C) and indentation-based sensing (STIP-I). STIP–C is designed to detect and measure the size and hardness of the inclusion. It assesses mechanical property changes caused by the tumor inside the tissue. STIP–I is designed to measure the pitting parameters and viscoelastic properties of the tissue. This system will assess the viscoelasticity changes caused by fluid retention within the tissue. STIP estimates mechanical and viscoelastic behavior changes in the tissue and provides the risk evaluation of an underlying health problem. Breast cancer risk assessment and edema severity level classification are the main applications of STIP. We estimate the breast cancer risk by incorporating the patient’s personal risk value into the STIP-C data associated with the tumor mechanical properties to improve the risk assessment accuracy. To classify the edema severity level, the STIP-I measures the pitting parameters and viscoelastic properties of the tissue. From these parameters, we build a Viscoelastic Pitting Recovery (VPR) model. The model illustrates the changes in tissue viscoelastic behavior associated with the edema severity level. Using the VPR model, we use the thresholding method to classify the edema cases. We also developed customized phantoms representing the different amounts of fluid retention in the tissue. The experimental result found a relationship between the amounts of pitted depth from STIP-I and the fluid amount of a phantom. In this dissertation, we developed and tested a portable tissue mechanical property estimation system. The interchangeable dual-mode STIP sensing probe and risk assessment methods were developed for the breast tumor malignancy and edema severity applications. / Electrical and Computer Engineering
74

Evaluating the Knowledge of Physical Activity and Dietary Guidelines Survey (Kopa-digs-40) as a Brief Online E-health Intervention With Adult African Americans: Predictors of High Knowledge of and Self-efficacy for Adherence to Guidelines

Radcliffe, Shamen January 2023 (has links)
In light of health disparities involving African Americans having disproportionately high rates of obesity, type II diabetes, cancer risk, heart disease and hypertension, the study was conducted with an all-Black adult sample (n= 470). Some 53.0% were female and the sample had a mean age of 32 years. The study evaluated the Knowledge of Physical Activity and Dietary Intake Guidelines Survey (KOPA-DIGS-40) as a new True-False knowledge test—with all True items. The study found moderately high levels of knowledge using the KOPA-DIGS-40. Findings using paired t-tests found evidence that ratings for (1) knowledge of guidelines and (2) self-efficacy for adherence to guidelines were significantly higher after taking the test. The study found noteworthy predictors of a higher KOPA-DIGS-40 score to be older age, higher education, and higher Body Mass Index. The study focused on three time periods (1-before the COVID-19 pandemic, 2-during the pandemic, 3-currently) and ratings on four health dimensions (1-physical health, 2-mental/emotional health, 3-physical activity level, 4-eating a healthy diet). Findings showed declines on the four dimensions during the pandemic, yet by Spring 2023 there were significant improvements—with a return by Spring 2023 to pre-pandemic levels. Findings suggested evidence of resilience after experiencing the stress of a global pandemic. Thus, a resilience theory and framework may be vital in guiding a future era of health disparities research with African Americans. Further, the study found an increase in social support during the pandemic, which continued into their current lives. Future research should continue to utilize the innovation of the genre of research reflected in this study’s use of the new Knowledge of Physical Activity and Dietary Intake Guidelines Survey (KOPA-DIGS-40)—as a True-False test with all True items; this follows from evidence the KOPA-DIGS-40 served as a brief online e-health intervention associated with increases in (1) knowledge of the guidelines and (2) self-efficacy for adherence to physical activity and dietary intake guidelines. Given the high rates of obesity, type II diabetes, cancer risk, heart disease and hypertension for African Americans, the findings make an important contribution to the literature—while suggesting future directions in research and interventions.
75

Female lung cancer and cooking practice: a case-control study in Hong Kong. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2004 (has links)
Chiu Yuk Lan. / "December 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 160-185) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
76

Public health implications of medical diagnostic radiation exposure

Gerstenmaier, Jan Frank 02 1900 (has links)
Radiation from Computed Tomography (CT) is now the major contributor to population radiation dose. Despite controversy around the dose-effect relationship of radiation from CT, the linear non-threshold (LNT) theory is endorsed by many authorities, and constitutes the basis of cancer risk estimates. The purpose of this study was (1) a literature review of radiobiological theories, and methods of dose saving stategies in CT; (2) to highlight the importance of dose saving in CT, and to demonstrate how dose can be saved in a radiology department: Following a 40% reduction in reference X-ray tube current for a CT of the urinary tract, the effecitve dose and estimated lifetime attributable risk of incident cancer due to this CT in a group (n=103) were reduced by 37% and 38% in an age and sex-matched group respectively. The literature review showed that the public health implications of CT radiation exposure remain uncertain. / Health Studies / M.A. (Public Health)
77

Genome-wide modeling of mutation spectra of human cancer-risk agents using experimental systems / Modélisation à l'échelle du génome des spectres de mutations des agents de risque de cancer humain en employant des systèmes expérimentaux

Zhivagui, Maria 30 November 2017 (has links)
Les génomes du cancer présentent une mosaïque de types de mutations. Trente signatures mutationnelles ont été identifiées à partir d'un grand nombre de tumeurs humaines primaires. Déchiffrer l'origine de ces signatures mutationnelles pourrait aider à identifier les causes du cancer humain. Environ 40% des signatures décrites sont d'origine inconnue, soulignant la nécessité de modèles expérimentaux contrôlés pour étudier l'origine de ces signatures. Au cours de mon travail de doctorat, j'ai caractérisé et utilisé des modèles in vitro et in vivo d'exposition aux cancérogènes, caractériser les signatures mutationnelles au niveau de génome entier de plusieurs composés cancérogènes pour lesquels le spectre de mutations n'était pas connu ou controversé. Tout d'abord, les conditions de cytotoxicités et genotoxicités pour chaque composé ont été établies et la formation d'adduits d'ADN a été évaluée. Suite au séquençage du gène TP53, on a effectué un séquençage au niveau du génome des clones MEF immortalisés dérivés de l'exposition à l'acrylamide, au glycidamide et à l'ochratoxine A. Le travail suggère une nouvelle signature mutationnelle unique pour l'acrylamide et médiée par son métabolite actif, le glycidamide. En fait, le motif des mutations de glycidamide, correspondant au profil de sa signature mutationnelle, a récapitulé les types de mutations attendus en fonction de l'analyse des adduits d'ADN. En outre, une analyse intégrée utilisant des modèles in vitro et in vivo suggère un manque de mutagénicité directe pour l'OTA avec une contribution potentielle d'un mode d'action lié à la production des radicaux libres à la signature mutationnelle OTA dans les MEF. Cette stratégie expérimentale simple et puissante peut faciliter l'interprétation des empreintes de mutations identifiées dans les tumeurs humaines, élucider l'étiologie du cancer et finalement soutenir la classification des cancers du CIRC en fournissant des preuves mécanistes / Cancer genomes harbour a mosaic of mutation patterns from which thirty mutational signatures have been identified, each attributable to a particular known or yet undetermined causal process. Deciphering the origins of these global mutational signatures in full could help identify the causes of human cancer, especially for about 40% of those signatures identified thus far that remain without a known etiological factor. Thus, well-controlled experimental exposure models can be used to assign particular mutational signatures to various mutagenic factors.During the time frame of my PhD work, I characterized and employed innovative in vitro and in vivo models of carcinogen exposure, namely, primary Hupki MEF cells, HepaRG and lymphoblastoid cell lines as well as rodent tumors. The cytotoxic and genotoxic conditions for each tested exposure compound were established and DNA adduct formation was assessed in select cases. Following a pre-screen by TP53 gene sequencing, genome-wide sequencing of immortalized Hupki MEF clones derived from exposure to acrylamide, glycidamide and ochratoxin A was performed, alongside whole genome sequencing of ochratoxin A induced rat renal tumors. The results reveal a novel mutational signature of acrylamide mediated by its active metabolite, glycidamide, a pattern that can be explained by the parallel analysis of individual glycidamide-DNA adducts. In addition, an integrative mutation analysis using in vitro and in vivo models suggests a lack of direct mutagenicity for OTA and possible indirect effects due to the ROS-mediated mode-of-action in MEF cells. The presented robust experimental strategy can facilitate the interpretation of mutation fingerprints identified in human tumors, thereby elucidating cancer etiology, elucidating the relationship between mutagenesis and carcinogenesis and ultimately providing mechanistic evidence for IARC’s carcinogen classification
78

Experiences of patients regarding oncology treatment and care at hospitals in Vhembe District of Limpopo Province

Ramutumbu, Neo Jacqueline 09 1900 (has links)
MCur / Department of Advanced Nursing Science / See the attached abstract below
79

Public health implications of medical diagnostic radiation exposure

Gerstenmaier, Jan Frank 02 1900 (has links)
Radiation from Computed Tomography (CT) is now the major contributor to population radiation dose. Despite controversy around the dose-effect relationship of radiation from CT, the linear non-threshold (LNT) theory is endorsed by many authorities, and constitutes the basis of cancer risk estimates. The purpose of this study was (1) a literature review of radiobiological theories, and methods of dose saving stategies in CT; (2) to highlight the importance of dose saving in CT, and to demonstrate how dose can be saved in a radiology department: Following a 40% reduction in reference X-ray tube current for a CT of the urinary tract, the effecitve dose and estimated lifetime attributable risk of incident cancer due to this CT in a group (n=103) were reduced by 37% and 38% in an age and sex-matched group respectively. The literature review showed that the public health implications of CT radiation exposure remain uncertain. / Health Studies / M.A. (Public Health)
80

Transgender male patients and hereditary breast cancer risk: broaching difficult topics to reduce healthcare disparities

Coltri, Julia Anne 30 July 2019 (has links)
No description available.

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