Neste estudo, foram determinadas as atividades de duas enzimas de membrana: alanina-aminopeptidase (AAP) e Y-glutamil-transpeptidase (YGT) e da enzima lisossomal N-acetil-B-D-glucosaminidase (NAG), bem como os níveis de proteína total (PT), albumina (ALB) e ácido delta-aminolevulínico (ALA) em urinas de indivíduos expostos ocupacionalmente ao chumbo (grupo exposto) e de indivíduos não expostos ao chumbo e nem a outras substâncias químicas (grupo controle). Todos os indivíduos apresentavam creatinina sérica inferior a 1,5 mg/dL. Ao mesmo tempo foram determinados os níveis sangfiíneos de chumbo (Pb-S) e aferidas pressão arterial diastólica (PD) e pressa-o arterial sistólica (PS). O objetivo foi investigar a toxicidade renal crônica do chumbo e sua possível correlação com a pressão arterial em indivíduos com função renal normal. A mediana de chumbo no sangue no grupo controle foi de 11,5 pg/dL contra 36,8 pg/dL no grupo exposto, mostrando-se dependente do tempo de exposição (p < 0,001). O valor mediano da NAG-U corrigido pela creatinina foi mais alto no grupo exposto (31,74 U/g creatinina) e significativamente diferente do grupo controle (25,28 U/g creatinina), p < 0,001. A atividade NAG-U se correlacionou com o Pb-S (p < 0,001), tempo de exposição (p < 0,001) e ALA-U (p < 0,001), mas não houve correlação com a pressão arterial. Os demais indicadores de função renal, Y GT-U, AAP-U, PT-U e ALB-U não se mostraram mais elevados no grupo controle e nem mostraram correlação com o Pb-S, tempo de exposição ou pressão arterial. A pressão arterial diastólica foi maior no grupo exposto (83 mmHg contra 78 mmHg no grupo controle) mas não se observaram diferenças quanto à pressão sistólica. Observaram-se correlações das pressoes arteriais diastólica e sistólica com tempo de exposição (p < 0,001 e p < 0,05 ) e com chumbo no sangue (p < 0,05 e p < 0,05 ) respectivamente, enquanto somente a pressão diastólica se correlacionou com o ALA-U (p < 0,05). / In the present study we determined the activity of two renal tubule membrane enzymes: alanine-aminopeptidase (AAP) and Y-glutamyl-transpeptidase (YGT), and of the renal tubule lysosomal enzyme N-acetyl-B-D-glucosaminidase (NAG), as well as the levels of total protein (TP), albumin (ALB) and delta-aminolevulinic acid (ALA) in the urine of individuais occupationally exposed to lead (exposed group) and in individuais not exposed to lead or to any other chemical substances (control group). All individuais presented serum creatinine levels of less than 1.5 mg%. All subjects were also submitted to measurement of blood lead levels (B-Pb) and of diastolic and systolic arterial pressure. The objective was to investigate the chronic renal toxicity of lead and its possible correlation with arterial pressure in individuais with normal renal function. Median B-Pb levels were 11.5 pg/dL for the controls versus 36.8 Pg/dL for the exposed group, with the level being proportional to time o f exposure (p < 0.001). Median NAG-U values corrected for creatinine were higher in the exposed group (31.74 U/g creatinine) and significantly different from the control (25.28 U/g creatinine), p < 0.001. NAG-U activity was correlated with B-Pb (p < 0.001), time of exposure (p < 0.001) and ALA-U (p < O. 001), but not with arterial pressure. The remaining indicators of renal function, YGT-U, AAP-U, TP-U and ALB-U were not more elevated in the control group and were not correlated with B-Pb, time of exposure or arterial pressure. Diastolic arterial pressure was higher in the exposed group (83 mmHg versus 78 mmHg for the controls), but the two groups did not differ in systolic pressure. Diastolic and systolic pressure values were correlated with time of exposure (p < 0.001 and p < 0.05) and blood lead (p < 0,05 e 0,05) respectively but only diastolic pressure was correlated with ALA-U ( p < 0.05).

O aporte artificial de nutrientes nos ambientes aquáticos tem favorecido a incidência de florações de cianobactérias, causando impactos na qualidade da água e colocando em risco a saúde humana. O gênero de cianobactéria Cylindrospermopsis, amplamente distribuído em água doce pelo mundo, é capaz de produzir diversas cianotoxinas, dentre elas saxitoxina e análogos. O objetivo deste trabalho foi elaborar um modelo de exposição referente à ingestão de água contaminada por saxitoxina e análogos através da recreação de contato primário e do consumo de água. Os dados de densidade de células de Cylindrospermopsis e de concentrações de saxitoxina e análogos na água bruta foram obtidos da Rede de Monitoramento de Qualidade de Águas Superficiais da CETESB (2015 e 2016) do reservatório Itupararanga. O modelo conceitual de exposição e o cálculo da ingestão diária crônica de saxitoxina e análogos consideraram: concentrações máxima e mínima de saxitoxina e análogos encontradas na água bruta do reservatório, vias de exposição, população exposta, taxa de ingestão de água, frequência e duração da exposição, peso corporal para adultos (maiores de 21 anos) e crianças (menores de 5 anos), para cenários de exposição relativos à recreação de contato primário e consumo de água potável. Os valores de células de cianobactérias estiveram entre 2.216 e 203.082 céls.mL-1 e as concentrações de saxitoxina e análogos estiveram entre 0,04 e 0,37 &#181;g equivalente STX..L-1. Os resultados obtidos na análise da água bruta do reservatório, estiveram abaixo do valor estabelecido na legislação brasileira para água potável (3 &#181;g equivalente STX.L-1), mas não atenderiam as especificações adotadas por Oregon e Ohio (0,3 &#181;g equivalentes STX.L-1) e à proposta em discussão no Comitê Permanente para Gestão Integrada da Qualidade da Água destinada ao Consumo Humano no Estado de São Paulo (0,13 &#181;g equivalente STX.L-1), indicando a possibilidade da ocorrência de efeito adverso à saúde em grupos sensíveis que utilizem água do reservatório, dependendo da eficiência de remoção dessas cianotoxinas no processo de tratamento. Os valores de ingestão diária crônica estimados, para recreação, variaram de 2,55 x 10-6 a 1,08 x 10-4 &#181;g equivalente STX. kg-1.dia-1 (adultos) e 2,78 x 10-9 a 4,35 x 10-4 &#181;g equivalente STX. kg-1.dia-1 (crianças). Para ingestão de água potável, esses valores variaram de 2,5 x 10-4 a 1,47 x 10-2 &#181;g equivalente STX. kg-1.dia-1 (adultos) e 5,36 x 10-5 a 2,55 x 10-2 &#181;g equivalente STX. kg-1.dia-1 (crianças). Esses valores indicaram que as crianças estão mais expostas que os adultos, fato preocupante, pois elas são mais sensíveis aos efeitos de substâncias tóxicas, e apesar de estudos indicarem efeitos da saxitoxina em cultura de células neurais, sua capacidade de atravessar a barreira hematoencefálica e de causar danos cognitivos em ratos, os efeitos da exposição crônica em humanos ainda são desconhecidos. Não foi possível estimar os riscos à saúde da população exposta à saxitoxina e análogos, pela falta de dados na literatura, porém o modelo de exposição proposto é um avanço para a identificação de lacunas para a condução da avaliação de risco à saúde humana considerando a exposição crônica. / The artificial enrichment of nutrients in aquatic environments has favored the incidence of cyanobacteria blooms, causing impacts on water quality and putting human health at risk. The genus of cyanobacteria Cylindrospermopsis, widely distributed throughout the world in freshwater environments, is able to produce cianotoxin, among them saxitoxin and its analogues. The objective of this work was to elaborate a model of exposure referring to the ingestion of water contaminated by saxitoxin and analogues through recreation of primary contact and water consumption. Cylindrospermopsis cell density and saxitoxin and analogues concentrations in surface water were obtained from the CETESB Surface Water Quality Monitoring Network for the Itupararanga reservoir in 2015 and 2016. The development of the conceptual model of exposure and the calculation of the chronic daily intake of saxitoxin and analogues, considered: maximum and minimum concentrations of saxitoxin and analogues found in the raw water of the reservoir, route of exposure, exposed population, rate of water intake, frequency and duration of exposure, body weight for adults (over 21 years) and children (under 5 years), for exposures scenarios concerning recreation of primary contact and consumption of drinking water. The values of cyanobacteria cells were between 2,216 and 203,082 cells.L-1 and the concentrations of saxitoxin and analogues were between 0.04 and 0.37 &#181;g STX equivalent. L-1. The comparison of these variables indicated a significant positive correlation between them. The results obtained in the raw water analysis of the reservoir were below the value established in Brazilian legislation for drinking water (3 &#181;g equivalent STX.L-1), but would not meet the specifications adopted by US states Oregon and Ohio (0.3 &#181;g equivalents.L-1) and the proposed value for the Standing Committee for Integrated Water Quality Management for Human Consumption in the State of São Paulo (0,13 &#181;g equivalent STX.L-1), indicating the possibility of adverse health effects in sensitive groups using water from the reservoir. Estimated chronic daily intake values, for recreation, ranged from 2.55 x 10-6 to 1.08 x 10-4 &#181;g STX equivalent. kg-1.day-1 (adults) and 2.78 x 10-9 to 4.35 x 10-4 &#181;g STX equivalent. kg-1.day-1 (children). For water intake, these values ranged from 2.5 x 10-4 to 1.47 x 10-2 &#181;g STX equivalent. kg-1 day-1 (adults) and 5.36 x 10-5 to 2.55 x 10-2 &#181;g STX equivalent. kg-1. day-1 (children). These values indicated that children are more exposed than adults, a worrying fact because they are generally more sensitive to the effects of toxic substances than adults, and although studies indicate that saxitoxin was able to cross the blood brain barrier and to cause cognitive damage in rats, as well as changes in neural cell cultures, the effects of chronic exposure in humans are still unknown. It was not possible to estimate the health risks of the population exposed to saxitoxin and the like, due to the lack of data in the literature, but the proposed exposure model is an advance for the identification of gaps for conducting the human health risk assessment considering the exposure chronic.

by Chan Tung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 85-102). / Abstract and questionnaire also in Chinese. / Abstract --- p.i / Chinese abstract --- p.ii / Table of contents --- p.iii / Acknowledgment --- p.v / List of tables --- p.vi / List of figures --- p.vii / Glossary of terms and abbreviations --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Asthma epidemiology --- p.1 / Chapter 1.2 --- Aim of study --- p.3 / Chapter Chapter 2 --- Literature review --- p.4 / Chapter 2.1 --- Definitions of asthma --- p.4 / Chapter 2.2 --- Questionnaire in asthma epidemiological surveys --- p.7 / Chapter 2.3 --- Asthma prevalence studies in Western populations --- p.9 / Chapter 2.4 --- Asthma prevalence studies in Hong Kong --- p.13 / Chapter 2.4.1 --- Adult asthma --- p.14 / Chapter 2.4.2 --- Childhood asthma --- p.15 / Chapter 2.4.3 --- Asthma mortality --- p.17 / Chapter 2.5 --- Environmental risk factors of asthma --- p.17 / Chapter 2.5.1 --- Allergens --- p.19 / Chapter 2.5.2 --- Air pollution --- p.23 / Chapter 2.5.3 --- Environmental tobacco smoke --- p.27 / Chapter 2.5.4 --- Viral infections --- p.29 / Chapter 2.5.5 --- Dietary factors --- p.30 / Chapter 2.5.6 --- Allergen avoidance --- p.32 / Chapter Chapter 3 --- Epidemiological survey --- p.34 / Chapter 3.1 --- Subjects and methods --- p.34 / Chapter 3.1.1 --- Subjects --- p.34 / Chapter 3.1.2 --- Written questionnaire --- p.35 / Chapter 3.1.3 --- Video questionnaire --- p.36 / Chapter 3.1.4 --- Bronchial hyperresponsiveness testing --- p.38 / Chapter 3.2 --- Results --- p.42 / Chapter 3.3 --- Discussion --- p.55 / Chapter Chapter 4 --- Environmental survey --- p.63 / Chapter 4.1 --- Subjects and methods --- p.63 / Chapter 4.1.1 --- Subjects --- p.63 / Chapter 4.1.2 --- Questionnaire survey --- p.63 / Chapter 4.1.3 --- Allergen sampling --- p.64 / Chapter 4.2 --- Results --- p.68 / Chapter 4.3 --- Discussion --- p.73 / Chapter Chapter 5 --- Overall discussion and conclusions --- p.81 / References --- p.85 / Appendix

No description available.

Second-hand smoke exposure (SHSe) causes significant morbidity and mortality in children. A large proportion of children with smoking parents do not live in smoke-free homes, however, to date, little is known about the prevalence of partial smoking restrictions and their efficacy in reducing children’s SHSe. Given the lack of convincing evidence on how to achieve further reductions in children’s SHSe in the home, the identification of the modifiable factors associated with childhood SHSe is imperative to reduce the burden of disease resulting from childhood SHSe. Analysis of the Omnibus Survey (OS) revealed that the prevalence of smoke-free homes in England did not increase significantly between 2006 and 2008. Only 30% of smokers reported a smoke-free home in 2008. However, during the same time period, the proportion of smokers (who did not have a smoke-free home) reporting that they did not smoke when in the same room as a child increased significantly from 62.5% to 74.8%. Using the Health Survey for England, biologically validated self-reported measures of child SHSe revealed that in 2008 and 2009 approximately 50% of children living with a smoking parent were not exposed to SHSe in the home (0.30ng/ml, 95% confidence interval 0.27-0.32ng/ml). Of the 50% of children who remained exposed inside the home, 29% had a parent that smoked in one room only in the home. These children had significantly lower cotinine concentrations (1.13ng/ml, 95% CI 1.05-1.22) than the 21% of children with smoking parents who smoked in 2 or more rooms in the home (2.36ng/ml, 95% CI 2.08-2.68ng/ml). Although smoking in one room equates to lower risk it does not equate to no risk and so interventions are required to change indoor smoking to outdoor smoking. The OS data found that good knowledge of SHS-related illnesses was predictive of both full and partial smoking restrictions in the home. Increases in the proportion of respondents with good knowledge occurred during 2003-2006, a period when frequent anti-SHS mass media campaigns were aired. A case-study evaluation of a brief mass media campaign in the North West and North East of England, which aimed to move smoking parents to smoke outside, was found to have no statistically significant effect on home smoking behaviour in the short term, however knowledge that SHS caused both heart attack and Sudden Infant Death Syndrome increased in this region following the campaign whilst simultaneous decreases were found in the rest of England. Following the identification of those children most exposed to SHS, and the modifiable factors associated with this exposure, this thesis suggests that a comprehensive multi-level approach to tobacco control policy, which includes emotive media campaigns which include information on SHS-related illnesses, will contribute to the continued reduction of childhood SHSe.

The purpose of the present study is to develop and explain a teaching aid for Spanish word recognition, to be presented as advance preparation for large-exposure reading.

In situations of mass disaster (1), which include airline crashes (2), terrorist attacks (2), large fires (3), and mass homicide (4), the human remains are often damaged beyond recognition (5). In these cases, bones and teeth are potentially the only acceptable source of deoxyribonucleic acid, or DNA (6). Previous studies have evaluated a plethora of techniques to purify DNA from hard tissue, but there is no consensus on the optimal process by which to extract and purify DNA from these samples. Not only are hard tissue samples difficult to process, in many cases the samples are subjected to extreme environmental conditions, such as high temperature. Thus, there is interest in obtaining information on DNA quality from samples exposed to high temperatures (7). This work hopes to fill the gap by: 1) optimizing a DNA extraction protocol from hard tissue; and 2) measuring the degree to which the DNA is degraded in an effort to link the quantity and quality of the DNA recovered to the outer appearance of the tooth. To accomplish this, individual teeth were burned in a furnace at 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, and 600 °C for 10, 20, and 30 minutes. The optimal extraction procedure utilized Amicon® Ultra-4 Centrifugal 30K filter devices and the QIAGEN MinElute Polymerase Chain Reaction (PCR) Purification Kit. Samples were quantified using the Quantifiler® Trio quantification kit to obtain the quantity and quality metrics. After heat exposure, each tooth was photographed and subsequently given a color designation or value: light yellow to beige teeth were assigned a value of 1; dark yellow to orange were assigned a value of 2; brown was assigned a value of 3; shiny black was assigned a value of 4; and black to light gray teeth were assigned a value of 5. Both carbonization and the early stages of calcination were observed. The mass of DNA per mass of tooth was determined by examining quantitative PCR (qPCR) results for both a large and small autosomal fragment. The degradation index, or DI, was also calculated from qPCR measurements. The results demonstrate a strong correlation between the quantity of DNA recovered, the quality of the DNA obtained, and the designated color value. The highest recovery rates were obtained from teeth assigned a color value of 1 (unaltered beige) or 2 (yellow to orange). These teeth were exposed to either room temperature, 100 °C or 200 °C. At temperatures exceeding 300 °C, the amount of DNA recovered drastically decreased and was inconsistent. Some of the samples subjected to temperatures at and above 300 °C resulted in no quantifiable DNA. In contrast, the DI results suggested that when the teeth were subjected to temperatures ≤ 100 °C, the quality of the DNA was good, wherein the DI value was approximately 1. At 200 °C, the temperature began to impact the DI value, which increased with time to the point where a DI was no longer able to be calculated because the large autosomal fragment could not be detected. In conclusion, the current work compares five different methods of DNA extraction to establish a best practice extraction procedure for these difficult samples. Furthermore, this work suggests that examination of the tooth’s appearance can be used to deduce whether successful DNA recovery is likely. In summary, the results demonstrate that when the tooth sample was assigned a color value of 1, the quantity and quality of the DNA obtained was high. Once the color value of the sample rose to 2, the quantity and quality of DNA varied greatly and the probative value of the sample was diminished. Samples that exhibited large color changes or had begun the calcination process resulted in no recoverable DNA.

Gambling constitutes an inherent part of British cultural landscape but due to its potential to cause significant detriments it remains controversial. The Gambling Act 2005 liberalised the UK gambling industry and created an environment where commercial gambling, although regulated, can be offered within a relatively free market setting and its consumption can be stimulated by advertising. The task of the law is to provide a framework where the need for customer choice, a flourishing market, and the respect for private liberties can be adequately balanced with the duty to protect vulnerable individuals such as minors. The Gambling Act has been positioned as containing sufficient protective measures to prevent minors from being harmed by gambling but there is still a relative paucity of research that focuses specifically on how this regime affects this age group. This thesis fills some of the gaps by analysing whether the existing legal and regulatory framework reconciled the conflicting priorities adequately. It uniquely combines legal doctrinal analysis with empirical evidence collected from a sample of British pupils to expose that the liberalisation of gambling has brought severe limitations on protecting minors that are not sufficiently counterbalanced by existing measures. This thesis demonstrates that the legal definition of prohibited gambling does not incorporate all activities that may lead to gambling-related harm. While the age verification measures adopted by online gambling providers appear to be successful, young people continue to have easy access to gambling in land-based venues and are exposed to significant volumes of gambling advertising that appeals to them but these factors are not sufficiently compensated by any holistic regulatory strategy. However, the thesis indicates that the correlation between fun and real gambling games should not be attributed to overlaps in minor's motivations for engaging in either form or to minors' lack of accurate differentiation between them.

Traumatic brain injury (TBI) is a serious public health concern. Although moderate and severe forms of TBI receive considerable attention, mild TBI accounts for the majority of all injuries. The first two aims of this work used a rodent model of mild blast to simulate primary injury (damage from the blast wave only). The first aim evaluated potential changes in interneurons containing the calcium-binding proteins calretinin or parvalbumin. In addition, morphological changes in astrocytes and microglia were assessed. Brains were analyzed 48 hours and one month following exposure to single or repeated blasts, with a focus on the hippocampus due to its integral role in learning and memory. Results showed significant region-specific alterations in microglia morphology 48 hours following blast. The absence of structural alterations in microglia one month following blast indicated that the regional hippocampal vulnerability may be transient. The second aim compared glial morphologies in the retina and brain (the lateral geniculate nucleus, superior colliculus, and visual cortex) 48 hours or one month following multiple blasts. Fiber degeneration has received considerable attention, however, less is known about the status of glia throughout the visual pathway following mild blasts. Although no structural alterations were detected, it is possible that alterations in glia occurred at a more acute time scale as changes in glia can be rapid and reversible. The final aim of this work focused on the immunocytochemical characterization of tau pathology in the visual cortices of human postmortem brains with advanced chronic traumatic encephalopathy (CTE). CTE is a devastating tauopathy associated with mild, repetitive TBIs. Although visual deficits are reported in CTE, the primary visual cortex is often spared. The main hypothesis under investigation was whether visual association areas would have tau pathology, despite sparing of primary visual cortex. In addition, a sub-class of interneurons containing parvalbumin was used to evaluate a potential cell-specific vulnerability. Results showed increased tau pathology in visual association areas in advanced CTE, that was largely absent from the primary visual cortex. There was no effect on parvalbumin positive interneurons. The results of this work provides valuable insight regarding potential cell-specific resistance to CTE pathology. / 2018-11-03T00:00:00Z

Although significant progress has been made in imaging devices during the past few decades, the photographs acquired by digital cameras are still far from perfection due to the physical limitations of hardware such as aperture, lens and sensor. This fact brings out the demand for study on image enhancement: a computational technique that aims to improve the interpretability or perception of information in photographs for human viewers. The work in this thesis mainly focuses on three tasks in image enhancement. / Finally, since the radiance of the real world spans several orders of magnitude and its dynamic range dramatically exceeds the capability of the current digital cameras, there often exist some undesirable over- or under-exposed regions in a photograph. The third part of this thesis aims at producing one great looking well-exposed image that is virtually impossible with a single exposure by compositing a stack of photos at different exposures taken with a conventional camera. Particularly, a simple but effective method is presented to describe how to take advantage of the gradient information to accomplish exposure composition in both static and dynamic scenes. Compared to conventional high dynamic range (HDR) imaging work, the proposed approach is quite appealing in practice since it is computationally efficient and easy to use, and frees users from the tedious radiometric calibration and tone mapping steps. / Firstly, since the camera sensor has limited resolution, the acquired images cannot capture the scene very detailedly. Hence, people often resort to a postprocessing technique called super-resolution (SR) to enhance the resolution of the captured images. In the first part of this thesis, two approaches are presented to address the challenging single image SR problem, which is to recover a high-resolution (HR) image from one low-resolution (LR) input. Specifically, a novel learning-based framework is designed specifically for face image SR task from the perspective of DCT domain. In addition, an efficient two-step scheme is developed to super-resolve generic image by exploiting the salient edges of the input LR image. / Secondly, due to the limitation of lens and aperture, some cameras cannot produce pleasant photographs with desired focus setting. For example, portrait photography that requires shallow depth of field (DOF) is not allowed when using the compact point-and-shoot cameras. In the second part of this thesis, a new and complete postprocessing-based focus editing system that is able to handle the tasks of focus map estimation, image refocusing and defocusing, is developed to overcome the optical limitations and create different kinds of novel photos with desired focus setting from an imperfect photo. / Throughout this work, extensive experiments on various real and synthetic image data are conducted to evaluate the performance of the proposed algorithms. / Zhang, Wei. / Adviser: Wai-Kuen Chan. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 116-125). / 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, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.