• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 74
  • 63
  • 10
  • 6
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 186
  • 88
  • 63
  • 38
  • 35
  • 31
  • 28
  • 24
  • 20
  • 19
  • 19
  • 18
  • 18
  • 18
  • 16
  • 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.
21

Neurological symptoms among printing workers exposed to organic solvents in Hong Kong.

January 1998 (has links)
Lee Nga Lan. / Thesis submitted in: June 1997. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references. / Abstract also in Chinese. / Abstract --- p.i / Acknowledgment --- p.iii / Table of contents --- p.iv / List of tables --- p.viii / List of figures --- p.x / Glossary of abbreviations --- p.xi / Chapter CHAPTER 1. --- INTRODUCTION --- p.1 / Chapter CHAPTER 2. --- BACKGROUND --- p.3 / Chapter 2.1 --- OUTBREAKS OF SOLVENT INDUCED NEUROPATHY IN MAN --- p.3 / Chapter 2.2 --- WORLD-WIDE INVESTIGATIONS ON ORGANIC SOLVENTS HAZARDS --- p.5 / Chapter 2.3 --- HEALTH EEFECTS OF ORGANIC SOLVENTS --- p.8 / Chapter 2.3.1 --- Effects on the Nervous System --- p.9 / Chapter (a) --- Peripheral Nervous System / Chapter (b) --- Central Nervous System / Chapter 2.3.2 --- Other Effects --- p.13 / Chapter 2.4 --- METHODOLOGICAL ISSUES IN THE INVESTIGATION OF SOLVENT NEUROTOXICITY --- p.14 / Chapter 2.4.1 --- Study Design --- p.15 / Chapter 2.4.2 --- Exposure Measurements --- p.17 / Chapter 2.4.3 --- Outcome Effects Measurements --- p.18 / Chapter 2.5 --- UNSOLVED PROBLEMS IN THE STUDY OF SOLVENT NEUROTOXICITY --- p.20 / Chapter 2.6 --- ORGANIC SOLVENTS IN THE PRINTING INDUSTRY --- p.21 / Chapter 2.7 --- PRINTING METHODS --- p.25 / Chapter 2.8 --- OFFSET LITHOGRAPHY --- p.27 / Chapter 2.8.1 --- Principles of Offset Lithography --- p.28 / Chapter 2.8.2 --- Image Carriers for Offset Lithography --- p.29 / Chapter 2.8.3 --- Lithographic Presses --- p.32 / Chapter 2.8.4 --- Printing Process --- p.34 / Chapter CHAPTER 3. --- STUDY OBJECTIVES AND METHODS --- p.37 / Chapter 3.1 --- OBJECTIVES --- p.37 / Chapter 3.2 --- METHODS --- p.38 / Chapter 3.2.1 --- Study Population --- p.38 / Chapter 3.2.2 --- Visits --- p.41 / Chapter 3.2.3 --- Workers' Health Assessment --- p.42 / Chapter 3.2.4 --- Air Sampling --- p.44 / Chapter 3.2.5 --- Definition of Exposures --- p.48 / Chapter 3.3 --- DATA ANALYSIS --- p.49 / Chapter CHAPTER 4. --- RESULTS --- p.51 / Chapter 4.1 --- RESPONSE RATE --- p.51 / Chapter 4.2 --- CHARACTERISTICS OF THE STUDY POPULATION --- p.53 / Chapter 4.2.1 --- Printing Companies --- p.53 / Chapter 4.2.2 --- Study Subjects --- p.56 / Chapter 4.3 --- HEALTH PROBLEMS OF STUDY SUBJECTS --- p.60 / Chapter 4.3.1 --- Sick Leave --- p.60 / Chapter 4.3.2 --- Prevalence of Subjective Symptoms --- p.61 / Chapter 4.3.3 --- Mean Number of Symptoms --- p.64 / Chapter 4.4 --- AIR SAMPLING RESULTS --- p.66 / Chapter 4.4.1 --- Mean Concentration Levels of Solvents --- p.71 / Chapter 4.4.2 --- Mean Concentration Levels of Solvents by Printing Plants --- p.73 / Chapter 4.4.3 --- Mean Concentration Levels of Solvents by Locations --- p.75 / Chapter 4.5 --- EXPOSURE-RESPONSE RELATIONSHIPS BETWEEN ORGANIC SOLVENTS AND SYMPTOMS --- p.77 / Chapter 4.6 --- RISK FACTORS FOR SUBJECTIVE SYMPTOMS --- p.85 / Chapter CHAPTER 5. --- DISCUSSIONS --- p.90 / Chapter 5.1 --- RESPONSE RATE --- p.90 / Chapter 5.2 --- SOURCES OF BIAS --- p.91 / Chapter 5.3 --- STUDY SUBJECTS --- p.92 / Chapter 5.4 --- SOLVENT EXPOSURES --- p.93 / Chapter 5.4.1 --- Occupational Hygiene --- p.93 / Chapter 5.4.2 --- Exposure Classification --- p.95 / Chapter 5.4.3 --- Chemical Interaction --- p.98 / Chapter 5.5 --- HEALTH PROBLEMS --- p.99 / Chapter CHAPTER 6. --- CONCLUSION --- p.103 / REFERENCES --- p.105 / APPENDICES --- p.120 / Appendices A1 to A9: Newspaper reports on polyneuropathy induced by organic solvents in a Hong Kong printing factory --- p.120 / Appendix B: Telephone follow up form --- p.129 / Appendix C: Letter to the printing factory employer --- p.130 / Appendix D: Subjective symptom questionnaire for solvent workers --- p.131 / Appendix E: Questionnaire for exposed group workers --- p.132 / Appendix F: Questionnaire for non-exposed group workers --- p.140 / Appendix G: NIOSH Sampling and Analytical Method 1400 --- p.145 / Appendix H: NIOSH Sampling and Analytical Method 1500 --- p.150 / "Appendix I: Chemical Analytical Method from Department of Hygiene, School of Public Health, Sun Yat Sen University of Medical Sciences" --- p.157 / Appendix J: Air Sampling Worksheet --- p.159 / BIBLIOGRAPHY --- p.162
22

The neurobehavioral effects of occupational exposure to organic solvents in Hong Kong printing workers.

January 2000 (has links)
Song Hong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves ). / Abstracts in English and Chinese; questionnaire in Chinese. / Abstract (English) --- p.i / Abstract (Chinese) --- p.iv / Acknowledgments --- p.vi / Table of Contents --- p.vii / List of tables --- p.x / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Printing industry and organic solvents exposure --- p.1 / Chapter 1.2 --- Risk of low level exposures to organic solvents --- p.2 / Chapter 1.3 --- Using neurobehavioral methods to study the subclinical effects --- p.3 / Chapter Chapter 2 --- Literature review --- p.4 / Chapter 2.1 --- Organic solvents and neurobehavioral impairment --- p.4 / Chapter 2.2 --- Methodology of Neurobehavioral Test --- p.6 / Chapter 2.2.1 --- Criteria for selecting test battery --- p.7 / Chapter 2.2.2 --- Standardization of neurobehavioral test battery --- p.8 / Chapter 2.2.3 --- Reliability and validity --- p.9 / Chapter 2.2.4 --- Confounding factors of neurobehavioral test --- p.10 / Chapter 2.3 --- Neurobehavioral effects of different levels of solvent exposures --- p.12 / Chapter 2.3.1 --- Positive results in field studies --- p.12 / Chapter 2.3.2 --- Negative results in field studies --- p.17 / Chapter 2.3.3 --- Dose-response relationship in the field studies --- p.18 / Chapter 2.3.4 --- To separate acute and chronic effects --- p.20 / Chapter 2.3.5 --- The long-term effects of solvent exposure --- p.21 / Chapter 2.4 --- Limitations of these studies --- p.23 / Chapter 2.5 --- Summary --- p.26 / Chapter Chapter 3 --- Aims and Objectives --- p.31 / Chapter 3.1 --- Aims of the present research --- p.31 / Chapter 3.2 --- Position of this study cm this research domain --- p.32 / Chapter Chapter 4 --- Subjects and Method --- p.33 / Chapter 4.1 --- Study design --- p.33 / Chapter 4.2 --- Study population and sampling --- p.33 / Chapter 4.2.1 --- Participation --- p.33 / Chapter 4.2.2 --- Exposed group --- p.34 / Chapter 4.2.3 --- Reference group --- p.34 / Chapter 4.2.4 --- Sample size estimation --- p.34 / Chapter 4.3 --- Data collection --- p.36 / Chapter 4.3.1 --- Exposure assessment --- p.36 / Chapter 4.3.1.1 --- Air sample measurements --- p.36 / Chapter 4.3.1.2 --- Biological monitoring --- p.38 / Chapter 4.3.2. --- Medical assessment --- p.38 / Chapter 4.3.2.1 --- Pre-test questionnaire --- p.39 / Chapter 4.3.2.2 --- Neurobehavioral assessment --- p.39 / Chapter 4.4 --- Data Analysis --- p.43 / Chapter 4.4.1 --- Data Processing --- p.43 / Chapter 4.4.2 --- Statistical analysis --- p.44 / Chapter 4.4.2.1 --- Descriptive analysis --- p.44 / Chapter 4.4.2.2 --- Identifying the main confounding factories --- p.44 / Chapter 4.4.2.3 --- Comparing the tests score adjusted for confounding --- p.45 / Chapter 4.4.2.4 --- Dose-response analysis --- p.45 / Chapter Chapter 5 --- Results --- p.47 / Chapter 5.1 --- Demographic characteristics of the subjects --- p.47 / Chapter 5.2 --- Comparison of the basic characteristics between the exposed group and the reference group --- p.48 / Chapter 5.3 --- Comparison of the symptoms between the exposed group and the reference group --- p.49 / Chapter 5.4 --- Comparison of the scores of neurobehavioral tests between the exposed group and the reference group --- p.51 / Chapter 5.5 --- Identifying potential confounding of neurobehavioral test --- p.51 / Chapter 5.5.1 --- Main confounding factors of NCTB test on performance tests --- p.51 / Chapter 5.5.2 --- Main confounding factors of Profile of Mood States --- p.54 / Chapter 5.6 --- Groups comparison of the neurobehavioral effects --- p.57 / Chapter 5.6.1 --- Comparison of the adjusted mean scores between the exposed group and the reference group --- p.57 / Chapter 5.6.2 --- Groups comparison of the adjusted tests score in Factories C and G respectively --- p.58 / Chapter 5.7 --- Exposure assessment --- p.61 / Chapter 5.7.1 --- Air sampling results of the printing factories --- p.62 / Chapter 5.7.2 --- Relationship between results of active and passive sampling systems --- p.63 / Chapter 5.7.3 --- Biological monitoring --- p.63 / Chapter 5.8 --- Dose-response relationship --- p.65 / Chapter Chapter 6 --- Discussion --- p.69 / Chapter 6.1 --- Findings of this study --- p.69 / Chapter 6.1.1 --- Subjective symptoms --- p.69 / Chapter 6.1.2 --- Neurobehavioral effects --- p.70 / Chapter 6.1.3 --- Exposure intensity --- p.72 / Chapter 6.1.4. --- Dose-response relationship --- p.75 / Chapter 6.2 --- Applications of the study results --- p.76 / Chapter 6.2.1 --- The need for prevention measures --- p.77 / Chapter 6.2.2 --- Contributing to re-setting of OELs --- p.77 / Chapter 6.2.3. --- The evidence on neurotoxicology --- p.78 / Chapter 6.3 --- Limitations of the study --- p.79 / Chapter 6.3.1. --- Possibility of bias --- p.79 / Chapter 6.3.2. --- Lack of historical hygiene measurement data --- p.80 / Chapter 6.3.3. --- Influence of workshift --- p.81 / Chapter 6.3.4. --- Combined exposures to noise and organic solvents --- p.82 / Chapter 6.4 --- Conclusion --- p.83 / Appendices --- p.84 / Appendix 1 --- p.84 / Appendix 2 --- p.97 / Appendix 3 --- p.102 / Appendix 4 --- p.103 / Appendix 5 The Administration of The WHO-NCTB Tests --- p.114 / Test 1 Profile of Mood States Test --- p.115 / Test 2. Simple Reaction Time Test --- p.116 / Test 3. Digit Span Test Test --- p.119 / Test 4. Santa Ana Test --- p.120 / Test 5. Digit Symbol Test --- p.122 / Test 6. Benton Visual Retention Test --- p.123 / Test 7. Pursuit Aiming Test --- p.125 / Appendix 6 --- p.126 / Reference List --- p.127
23

Effect of low alcohol consumption during pregnancy on the risk of small-for-gestational-age (SGA) birth

St-Arnaud-Trempe, Emmanuelle. January 2008 (has links)
Although the association between high maternal alcohol consumption and adverse reproductive outcomes is well established, the effect of lower levels of consumption during pregnancy is unclear; few studies have investigated this exposure. A hospital-based case-control study of small-for-gestational age (SGA) newborns (birth weight below the 10th percentile, according national standards for gestational age and sex) was conducted in Montreal between 1998 and 2000. Controls were born at the same hospital and during the same period with birth weight at or above the 10th percentile. This analysis aims at investigating the effect of low alcohol consumption (0.25 to 3 alcoholic drinks weekly) during pregnancy on the risk of small-for-gestational-age (SGA) birth. Independent effects of wine, beer and spirits and of paternal alcohol consumption before conception were also assessed. The logistic regression analysis showed no significant effect of light maternal drinking during pregnancy on the risk of SGA birth. The association was also studied separately for consumption of wine, beer and spirits, and likewise for paternal alcohol consumption, with similarly negative results.
24

Omissão do segundo dia da medicação antiemética como estratégia para a redução do custo da profilaxia de náuseas e vômitos induzidos por quimioterapia: resultados de um estudo fase III / The omission of day 2 of Antiemetic Medications is a cost saving strategy for improving chemotherapy-induced nausea and vomiting control: Results of a randomized phase III trial

Lajolo, Paula Philbert [UNIFESP] 30 July 2008 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-30. Added 1 bitstream(s) on 2015-08-11T03:25:42Z : No. of bitstreams: 1 Publico-10756.pdf: 198016 bytes, checksum: b1b248dd88de1aeab5859b81fa05e4c2 (MD5) / INTRODUÇÃO: Os antagonistas 5HT-3 e corticosteróides são drogas importantes no controle da emese induzida por quimioterapia Apresentam controle de 50-80% da emese aguda porém controlam menos de 50% da emese tardia induzida por quimioterapia. Em estudo prévio realizado em nossa instituição, observou-se que o controle da emese tardia poderia ser melhorado com a omissão do segundo dia dos antagonistas 5HT-3. Reportamos aqui os resultados de um estudo fase III confirmando os achados prévios PACIENTES E MÉTODOS: Estudo fase III randomizado e duplo-cego foi realizado na FMABC Santo André/Brasil. Pacientes submetidos a esquemas quimioterápicos alta e moderadamente emetogênicos pela 1ª vez receberam Ondasetron 16mg e Dexametasona 20 mg IV antes da quimioterapia no Dia 1. Foram então randomizados em dois grupos. Grupo A recebeu metoclopramida VO 10mg 8/8hs, Granisetron VO 0,5mg/dia,e dexametasona VO 8mg /dia por 2 dias, a partir do dia 2 (dias 2 e 3). Metoclopramida VO 10 mg 8/8 hs foi continuada no dia 4. Grupo B recebeu placebo no dia 2 e o mesmo esquema de drogas dia 3 e dia 4. Pacientes foram entrevistados no dia 1 e dia 6. RESULTADOS: 73 pacientes foram incluídos no estudo. Os grupos foram bem balanceados em relação as suas características clinicas com exceção ao melhor controle da emese aguda no grupo A (p=0,04). Proteção completa de náuse a e vômito tardios (do dia 2 ao 5 ), foi semelhante em ambos os grupos (30% vs. 32%; p=0.5). Em análise multivariada, tanto a proteção completa da emese aguda (p=0.001) quanto grupo de estudo (p=0.06) estavam independentemente relacionados à proteção completa da náusea e vômito tardios. Selecionando apenas os pacientes que obtiveram controle completo da emese na fase aguda, pacientes do grupo B obtiveram maior proteção da emese tardia (85% vs 50% ,p=0,02). CONCLUSÃO: A omissão da medicação antiemética no dia 2 representa uma estratégia para redução do custo da profilaxia da emese tardia induzida pela quimioterapia. / BACKGROUND: Nausea and vomiting are important symptoms observed in cancer patients. In a previous study we showed that delayed chemotherapyinduced nausea and vomiting (CINV) control could be potentially improved by skipping the administration of a 5HT3-antagonist on day 2. We report here a trial confirming our previous findings. PATIENTS/METHODS: A phase-IIIrandomized- placebo-controlled trial was conducted in which patients received (IV) ondansetron 16mg, dexamethasone 20mg and ranitidine 50mg before highly/moderately emetogenic chemotherapy (day 1).Starting on day 2, all patients received metoclopramide 10mg PO q8 hours (days 2,3 and 4, Dexamethasone 8mg QD (days 2 and 3) and Ranitidine 150mg q12 hours (days 2 and 3). Patients were randomized to receive either Granisetron 0.5mg PO (days 2 and 3) (Group A) or Placebo instead for Granisetron on day 2 and Granisetron 0.5mg on day 3 and 4 (Group B) RESULTS: 73 patients were enrolled. Groups were similar regarding clinical characteristics, despite better control during the acute phase of CINV in group A (p=0.04). Complete delayed protection from nausea/vomiting (DCPNV) from day 2 to 5 was similar in both groups. (30% vs. 32%; p=0.5). Analyzing DCPNV by logistic regression multivariate analyses, acute complete protection from nausea/vomiting (ACPNV) (p=0.001) and study group (p=0.06) were independently associated with DCPNV. Selecting patients who achieved ACPNV, we observed that group B had a superior DCPNV (85% vs 50%, p=0.02). CONCLUSION: DCPNV can be improved just by skipping day 2 of 5HT3- antagonists. Future studies should compare this inexpensive strategy with NK1- antagonists or second generation 5HT3-antagonists. Key words: delayed chemotherapy-induced nausea and vomiting, tachyphylaxis, cost- saving regimen, antiemetics, Granisetron/administration and dosage. / TEDE / BV UNIFESP: Teses e dissertações
25

An investigation into the neurological and neurobehavioural effects of long-term agrichemical exposure among deciduous fruit farm workers in the Western Cape, South Africa

London, Leslie 19 April 2017 (has links)
It is increasingly being recognised that agrichemical exposure may have adverse chronic health effects in humans, particularly on central nervous system function. However, much of this evidence sterns from studies relating to the effects of acute intoxications (i.e. short-term high dose exposures) and little data exist on the chronic effects of long-term low-dose exposures to agrichemicals in the absence of acute poisoning. Such a finding would have substantial public health implications for prevention and control of chronic morbidity and mortality. This is particularly important in South Africa, where a sizeable portion of the rural population are employed in agricultural work, often under extremely unhealthy living and working conditions, and where occupational agrichemical exposures appear to be substantial. To address this question, this study investigated the prevalence of neurological and neurobehavioural abnormalities amongst 247 fruit farm workers in the Kouebokkeveld in the Western Cape, of whom 163 were current agrichemical applicators. Outcomes measured included neurological symptoms, peripheral vibration sense, motor tremor, as well as performance on the World Health Organisation Neurobehavioural Core Test Battery (WHO NCTB) and a set of neurobehavioural tests based on the Information Processing model of cognitive psychology. These latter tests have been developed in South Africa for subjects of low educational levels and aim to by-pass the powerful effects of culture that complicate traditional neuropsychological testing, which may mask the smaller effects due to occupational chemical exposures. Cumulative, and average lifetime intensity of exposure to organophosphates were estimated using a job- exposure matrix based on a combination of secondary industry data, interview reports and farmer records. Confounders measured included age, education, smoking and alcohol habits, non-occupational exposure to agrichemicals and other potential neurotoxins, past medical history and usage of personal protective equipment. The study results confirmed low levels of education and high alcohol consumption amongst the sample of farm workers. Multiple logistic and linear regression were used to identify exposure-effect relationships and to control for confounding. Neurological symptoms were significantly associated with a history of previous pesticide poisoning, although this may have arisen as a result of reporting bias. Vibration sense and the neurobehavioural tests exhibited associations with established covariates, and regression modelling of the WHO NCTB tests was remarkably similar to findings in another study of solvent-exposed factory workers in South Africa. None of the vibration sense, tremor or neurobehavioural outcomes were associated with past agrichemical poisoning in the sample, and only two tests showed significant relationships with long-term occupational exposure. These included the Pursuit Aiming subtest of the WHO NCTB and one of the tests of long-term semantic memory in the Information Processing tests. However, the strength of these the associations were small (partial r²s less than 2%) and these findings may have occurred due to chance arising from multiple comparisons. The neurobehavioural tests based on the Information Processing model appeared to offer little improvement on the WHO NCTB in terms of being less sensitive to cultural effects, although some evidence was present that tests of semantic access were able to detect occupational effects and were less sensitive to education. The absence of a demonstrable and consistent long-term agrichemical exposure-effect relationship appears to suggest that long-term agrichemical exposure is not associated with adverse chronic nervous system effects, although the lack of organophosphate specificity in construction of exposure indices in the job-exposure matrix may partly contribute to this finding. Recommendations to improve the characterisation of agrichemical exposures at farming work place are made, as well as suggestions concerning the role of biological monitoring for agrichemicals, improving working and living conditions on South African farms, and methods of neurological and neurobehavioural assessment in occupational health.
26

Effect of low alcohol consumption during pregnancy on the risk of small-for-gestational-age (SGA) birth

St-Arnaud-Trempe, Emmanuelle. January 2008 (has links)
No description available.
27

The perceptions, expectations, fears and needs of chemically dependent youth in a rehabilitation centre about being reintegrated into their family systems

Matsimbi, Jeaneth Linki 06 1900 (has links)
Drug abuse is a very common problem these days; and this problem is especially rampant among the young people of South Africa. Early problems in family management, the antisocial behaviour of the child, and peer pressure and rejection ignite the early onset of substance abuse. Treatment programmes and therapeutic methods to treat chemical dependency are available and utilised, but the high relapse rate and lack of support from family members and dysfunctional families, as well as the fears and challenges expressed by in-patient youth about being reintegrated with their families and a lack of supporting literature in this regard remain a cause for concern and need to be considered by the social work profession in order to plan effective intervention strategies. In response to this situation a research project was undertaken with the purpose of exploring and describing the perceptions, expectations, fears and needs of chemically dependent youth in a rehabilitation centre about being integrated into their family systems in an attempt to forward recommendations to assist social workers in rendering effective therapeutic services to service users in rehabilitation centres who have a substance abuse problem. A qualitative approach was utilised following an explorative, descriptive and contextual research design. The study was conducted at an in-patient rehabilitation centre called the Dr Fabian and Florence Ribeiro Treatment Centre in Cullinan, Gauteng Province in South Africa. Data were collected by means of semi-structured interviews. A sample of participants was selected by using purposive sampling from a population of service users in the Dr Fabian and Florence Ribeiro Centre who are chemically dependent. Data were analysed according to the framework provided by Tesch (cited in Creswell, 2003). Guba‘s model (cited in Krefting, 1991) was employed for data verification. The research findings point to the fact that participants had both negative and positive perceptions about going back to their respective families. On the one hand, there were negative perceptions shared. These were founded on a feeling of worry about the fact that their families criticised them a lot or that their families would not accept that they had changed, would still treat them like addicts, and not trust them. Furthermore, they feared relapse, triggers in their environment and family members who were abusing a substance. On the other hand, some participants perceived the reintegration with their families, following treatment, in a positive light as they were looking forward to joining them again after being in v treatment for three months.They were excited about the fact that they had been granted an opportunity where they could show their families that they have changed and have the chance of starting a new life. Moreover, part of the research findings point to the fact that some of the participants‘ families had already organised employment, a place for them to stay and financial assistance. From the research findings it became clear that the participants harboured the following expectations towards the families with whom they were reuniting: They need the family‘s love and support; to trust them again: to mend severed relationships and spend quality time together; to provide practical and material help, and for the family to be educated on addiction and for the family to accompany them to aftercare. In terms of research findings directed at the site (i.e., the rehabilitation centre) where the research was conducted the participants indicated that they needed more activities, they would like their families to be part of their recovery process, and expressed the need for individual sessions apart from group sessions and aftercare services. In terms of recommendations it was apparent that community members, community organisations and the government sector need to develop and launch chemical substance abuse prevention and awareness programmes through various media, (i.e. articles in newspapers, magazines, talks and documentaries on radio and television, community gatherings and meetings in all communities). Moreover, it is recommended that parents should take responsibility for monitoring and countering substance abuse in their children. Families need to be empowered through talks, attending parenting skills training, workshops and group meetings. South Africa needs to develop a policy focusing on families. Furthermore, it is recommended that treatment centres need to provide individual sessions, family therapy, aftercare services and more extramural activities, if these are not included in their treatment regime. / Social Work / M.A. (Social Science)
28

Calcium-Aluminate as Biomaterial : Synthesis, Design and Evaluation

Lööf, Jesper January 2008 (has links)
<p>In this thesis different aspects of calcium-aluminate (CA) as biomaterial are presented. Calcium aluminate is a chemically bonded ceramic with inherent properties making it suitable for use as biomaterial in some applications. In this thesis the emphasis is put on the basic chemical, physical and mechanical properties that may be achieved using the CA system as well as synthesis of the CA raw material. The basis for using CA in any application is the synthesis of the raw material. Different synthesis routes for producing CA are presented with focus on high temperature routes and the micro-structural and phase development during synthesis. As a base for further understanding of the CA properties a thorough outline of the reaction chemistry for CA is presented also including a description of how the reactions may be controlled and how formulations can be designed. The surface reactions of CA when subjected to simulated body fluid showed that CA is <i>in vitro</i> bioactive. An <i>in vivo</i> study in teeth also indicates that CA produces apatite at the tooth material interface. Dental materials are subjected to a harsh environment in the mouth with high mechanical forces, erosion and thermal changes. Also the demands on precise handling characteristics are high. For these reasons the <i>in vitro</i> evaluation of physical and mechanical properties are important. In this work several mechanical and physical properties of Ca-based formulations for dental applications has been tested using different methods. Some attention is also put on the specific characteristics of CA and the difficulties that arise when new material classes needs to be tested according to consensus standard methods. Finally studies on a CA-based formulation intended for Vertebroplasty is presented. The studies include basic mechanical properties as well as testing the material in an <i>in vitro</i> model utilising synthetic cancellous bone.</p>
29

Chemical tagging with APOGEE: discovery of a large population of N-rich stars in the inner Galaxy

Schiavon, Ricardo P., Zamora, Olga, Carrera, Ricardo, Lucatello, Sara, Robin, A. C., Ness, Melissa, Martell, Sarah L., Smith, Verne V., García-Hernández, D. A., Manchado, Arturo, Schönrich, Ralph, Bastian, Nate, Chiappini, Cristina, Shetrone, Matthew, Mackereth, J. Ted, Williams, Rob A., Mészáros, Szabolcs, Allende Prieto, Carlos, Anders, Friedrich, Bizyaev, Dmitry, Beers, Timothy C., Chojnowski, S. Drew, Cunha, Katia, Epstein, Courtney, Frinchaboy, Peter M., García Pérez, Ana E., Hearty, Fred R., Holtzman, Jon A., Johnson, Jennifer A., Kinemuchi, Karen, Majewski, Steven R., Muna, Demitri, Nidever, David L., Nguyen, Duy Cuong, O'Connell, Robert W., Oravetz, Daniel, Pan, Kaike, Pinsonneault, Marc, Schneider, Donald P., Schultheis, Matthias, Simmons, Audrey, Skrutskie, Michael F., Sobeck, Jennifer, Wilson, John C., Zasowski, Gail 11 February 2017 (has links)
Formation of globular clusters (GCs), the Galactic bulge, or galaxy bulges in general is an important unsolved problem in Galactic astronomy. Homogeneous infrared observations of large samples of stars belonging to GCs and the Galactic bulge field are one of the best ways to study these problems. We report the discovery by APOGEE (Apache Point Observatory Galactic Evolution Experiment) of a population of field stars in the inner Galaxy with abundances of N, C, and Al that are typically found in GC stars. The newly discovered stars have high [N/Fe], which is correlated with [Al/Fe] and anticorrelated with [C/Fe]. They are homogeneously distributed across, and kinematically indistinguishable from, other field stars within the same volume. Their metallicity distribution is seemingly unimodal, peaking at [Fe/H] similar to -1, thus being in disagreement with that of the Galactic GC system. Our results can be understood in terms of different scenarios. N-rich stars could be former members of dissolved GCs, in which case the mass in destroyed GCs exceeds that of the surviving GC system by a factor of similar to 8. In that scenario, the total mass contained in so-called 'first-generation' stars cannot be larger than that in 'second-generation' stars by more than a factor of similar to 9 and was certainly smaller. Conversely, our results may imply the absence of a mandatory genetic link between 'second-generation' stars and GCs. Last, but not least, N-rich stars could be the oldest stars in the Galaxy, the by-products of chemical enrichment by the first stellar generations formed in the heart of the Galaxy.
30

Ultra-sensitive carbon based molecular sensors

Huang, Jingfeng January 2015 (has links)
This thesis presented the study of carbon-based materials for ultra-sensitive molecular sensing. Reduced Graphene Oxide (rGO), a 2-dimensional one-atomic layer thick carbon material, had the advantage of low-cost, aqueous and industrial-scalable production route. Using rGO as the transducer platform could potentially lower the cost of sensors down to a few dollars per chip. However, there were still limitations in rGO that prevented its widespread usage as a biosensor transducer or in electronics: its low electrical conductivity and large electrical deviations. This thesis was structured to understand and solve these problems for transducer application. The thesis could be broken down into 3 parts: The first part of the thesis presented the critical review of the background and limitations of graphene research, followed by the background and importance of biosensor developments for the detection of sweat sodium ions and circulatory Interleukin-6 proteins. The second part of the thesis tested the hypothesis that the rGO limitations could be eliminated to create a highly sensitive biosensor transducer via (A) improving rGO synthesis (B) pristine Carbon Nanotubes-rGO hybrid film and (C) growth of rGO. The mechanism of ultra-large graphene oxide synthesis and graphene oxide growth was also elucidated in this section. The third part of the thesis then presented the fabrication and test of the practical and homogenous carbon-based biosensor using the transducer synthesized earlier. The thesis showed that through proving the hypothesis correct, it enabled the synthesis of an all organic sodium ion sensor with integrated pump and an ultra-sensitive interleukin-6 bio-sensor. Both of these novel sensors were able to detect the respective molecules in their physiological ranges.

Page generated in 0.0706 seconds