O álcool é uma das substâncias psicoativas mais consumidas mundialmente e seu uso por mulheres em idade reprodutiva, em particular, tem representado grande preocupação por parte de especialistas e da sociedade em geral. Apesar dos efeitos adversos associados ao ato de ingerir bebidas alcoólicas durante a gestação ser bastante documentados e conhecidos, sabe-se que uma parcela de mulheres grávidas tem dificuldades em abandonar o hábito. O consumo excessivo de álcool durante a gravidez tem sido associado com a síndrome fetal pelo álcool (FAS), caracterizada por crianças com dificuldades comportamentais e de aprendizado. Entretanto, devido ao sentimento de culpa e medo de ações punitivas, mulheres raramente admitem terem utilizado álcool durante a gestação. Como resultado, uma série de marcadores biológicos tem sido estudada para se diagnosticar a exposição fetal ao etanol. Dentre os marcadores utilizados estão os ésteres etílicos de ácidos graxos (FAEE), que podem ser detectados em amostras de mecônio de recém-nascidos. No presente trabalho, um método analítico foi desenvolvido visando a detecção de oito FAEEs em amostras de mecônio e aplicada em amostras coletadas de recém-nascidos cujas mães admitiram ou não o uso de etanol durante a gestação. A microextração em fase sólida por Headspace (HS-SPME), uma técnica de preparação de amostras relativamente recente, foi utilizada para análise. Os FAEEs foram identificados e quantificados por cromatografia gasosa/espectrometria de massas (GC/MS), operado no modo de ionização química. Os correspondentes ésteres etílicos deuterados foram sintetizados e utilizados como padrão interno. Os limites de quantificação (LOQ) obtidos foram abaixo de 150 ng/g e limites de detecção (LOD) foram abaixo de 100ng/g para todos os analitos. O método mostrou boa linearidade na concentração estudada (LOQ-2000ng/g), com coeficiente (r2) melhor que 0.98. Os valores de precisão apresentaram coeficientes de variação menores que 15% para todos os FAEEs estudados. Quando o método foi aplicado em amostras de mecônio, foi possível detectar níveis de alguns FAEEs de recém-nascidos não suspeitos a exposição fetal ao etanol. / Alcohol is the main psychoactive drug consumed worldwide and its increasing use by young women has been a great problem point out by specialists in the subject. Although the adverse effects associated to the habit of drinking alcoholic beverages during gestation being very much documented, it is known that a considerable number of pregnant women have difficulties to abandon the habit. Excessive alcohol use during pregnancy has been associated with Fetal Alcohol Syndrome (FAS) characterized by children with cognitive and behavioral disorders. However, because of denial, embarrassment and fear, maternal reports of gestational use of alcohol are often inaccurate. Consequently, a series of biomarkers have been studied to diagnose fetal exposure to alcohol. Recently, fatty acid ethyl esters (FAEE) have been studied as biomarkers found in meconium of neonates exposed in utero. In the present work, an analytical method was developed aiming the detection of eight FAEEs in meconium samples and applied to real specimens collected from newborns whose mothers admitted or not the use of alcohol during pregnancy. Headspace solid-phase microextraction (HS-SPME), a relatively recent sample preparation technique, was used for analysis. FAEEs were identified and quantified by gas chromatography/mass spectrometry (GC/MS), operated in chemical ionization mode. The corresponding deuterated ethyl esters were synthesized and used as internal standards. The lower limits of quantification (LOQ) obtained were below 150ng/g and limits of detection (LOD) were bellow 100ng/g for all analytes. The method showed good linearity in the range of concentration studied (LOQ-2000ng/g), with coefficient of linearity better than 0.98. The precision assay, given by the relative standard deviation (RSD) of the method was lower than 15% for all FAEEs studied. When the method was applied to real samples, it was possible to detect trace levels of some FAEEs from non-suspected ethanol exposed newborns.

O álcool é uma das substâncias psicoativas mais consumidas mundialmente e seu uso por mulheres em idade reprodutiva, em particular, tem representado grande preocupação por parte de especialistas e da sociedade em geral. Apesar dos efeitos adversos associados ao ato de ingerir bebidas alcoólicas durante a gestação ser bastante documentados e conhecidos, sabe-se que uma parcela de mulheres grávidas tem dificuldades em abandonar o hábito. O consumo excessivo de álcool durante a gravidez tem sido associado com a síndrome fetal pelo álcool (FAS), caracterizada por crianças com dificuldades comportamentais e de aprendizado. Entretanto, devido ao sentimento de culpa e medo de ações punitivas, mulheres raramente admitem terem utilizado álcool durante a gestação. Como resultado, uma série de marcadores biológicos tem sido estudada para se diagnosticar a exposição fetal ao etanol. Dentre os marcadores utilizados estão os ésteres etílicos de ácidos graxos (FAEE), que podem ser detectados em amostras de mecônio de recém-nascidos. No presente trabalho, um método analítico foi desenvolvido visando a detecção de oito FAEEs em amostras de mecônio e aplicada em amostras coletadas de recém-nascidos cujas mães admitiram ou não o uso de etanol durante a gestação. A microextração em fase sólida por Headspace (HS-SPME), uma técnica de preparação de amostras relativamente recente, foi utilizada para análise. Os FAEEs foram identificados e quantificados por cromatografia gasosa/espectrometria de massas (GC/MS), operado no modo de ionização química. Os correspondentes ésteres etílicos deuterados foram sintetizados e utilizados como padrão interno. Os limites de quantificação (LOQ) obtidos foram abaixo de 150 ng/g e limites de detecção (LOD) foram abaixo de 100ng/g para todos os analitos. O método mostrou boa linearidade na concentração estudada (LOQ-2000ng/g), com coeficiente (r2) melhor que 0.98. Os valores de precisão apresentaram coeficientes de variação menores que 15% para todos os FAEEs estudados. Quando o método foi aplicado em amostras de mecônio, foi possível detectar níveis de alguns FAEEs de recém-nascidos não suspeitos a exposição fetal ao etanol. / Alcohol is the main psychoactive drug consumed worldwide and its increasing use by young women has been a great problem point out by specialists in the subject. Although the adverse effects associated to the habit of drinking alcoholic beverages during gestation being very much documented, it is known that a considerable number of pregnant women have difficulties to abandon the habit. Excessive alcohol use during pregnancy has been associated with Fetal Alcohol Syndrome (FAS) characterized by children with cognitive and behavioral disorders. However, because of denial, embarrassment and fear, maternal reports of gestational use of alcohol are often inaccurate. Consequently, a series of biomarkers have been studied to diagnose fetal exposure to alcohol. Recently, fatty acid ethyl esters (FAEE) have been studied as biomarkers found in meconium of neonates exposed in utero. In the present work, an analytical method was developed aiming the detection of eight FAEEs in meconium samples and applied to real specimens collected from newborns whose mothers admitted or not the use of alcohol during pregnancy. Headspace solid-phase microextraction (HS-SPME), a relatively recent sample preparation technique, was used for analysis. FAEEs were identified and quantified by gas chromatography/mass spectrometry (GC/MS), operated in chemical ionization mode. The corresponding deuterated ethyl esters were synthesized and used as internal standards. The lower limits of quantification (LOQ) obtained were below 150ng/g and limits of detection (LOD) were bellow 100ng/g for all analytes. The method showed good linearity in the range of concentration studied (LOQ-2000ng/g), with coefficient of linearity better than 0.98. The precision assay, given by the relative standard deviation (RSD) of the method was lower than 15% for all FAEEs studied. When the method was applied to real samples, it was possible to detect trace levels of some FAEEs from non-suspected ethanol exposed newborns.

Το αντικείμενο της διατριβής αυτής είναι η μελέτη της διαστρωματικής (cross-layer) προσέγγισης ανάπτυξης ασύρματων δικτύων κατανεμημένης λειτουργίας με απαιτήσεις επικοινωνίας πραγματικού χρόνου και περιορισμένους διαθέσιμους πόρους. Επιπλέον βασικό στόχο αποτελεί και η σχεδίαση, πρόταση αντίστοιχης αρχιτεκτονικής η οποία στοχεύει στη βέλτιστη διαχείριση διαθεσίμων δικτυακών πόρων σε καταστάσεις συμφόρησης του δικτύου και κατά συνέπεια στην βελτίωση της απόδοσης αυτού. Μέσα από μελέτες στα πλαίσια της διατριβής αναδεικνύεται η σημασία του φαινομένου συμφόρησης ως κύριου παράγοντα σπατάλης δικτυακών πόρων καθώς και οδήγησης του δικτύου σε κατάσταση κορεσμού με αρνητική επίπτωση σε όλες τις παραμέτρους απόδοσης του δικτύου. Στόχος, λοιπόν, της προτεινόμενης επικοινωνιακής αρχιτεκτονικής είναι η αποφυγή του φαινομένου συμφόρησης έτσι ώστε το δίκτυο να οδηγείται δυναμικά σε ένα σταθερό σημείο απόδοσης (όσο αυτό είναι δυνατό) το οποίο θα επιτρέπει στο δίκτυο να αποδίδει όσο το δυνατόν καλύτερα αποφεύγοντας τη ίδια στιγμή άσκοπη σπατάλη πόρων. Βασική παράμετρος στη σχεδίαση αποτελεί η συμβατότητα τόσο ως προς σημαντικό εύρος διαθέσιμων πρωτοκόλλων σε διάφορα επίπεδα, όσο και ως προς τη δυνατότητα συνύπαρξης κόμβων που ενσωματώνουν την προτεινόμενη αρχιτεκτονική με κόμβους χωρίς αυτήν. Η προτεινόμενη αρχιτεκτονική υλοποιήθηκε στα πλαίσια γνωστού και αξιόπιστου δικτυακού εξομοίωση. Αξιολόγηση της υλοποίησης αυτής μέσα από μεγάλο αριθμό πειραμάτων έδειξε επίτευξη του στόχου καθώς το φαινόμενο της συμφόρησης αντιμετωπίστηκε σε όλες τις περιπτώσεις με σημαντικά οφέλη στην απόδοση του δικτύου και διαχείριση των πόρων. Επιπλέον, λόγω του μεγάλου βαθμού παραμετροποίησης αποτελεί ιδανική βάση για μελλοντικές προεκτάσεις. / This objective of this dissertation is the study of cross-layer approach applied on the development of distributed wireless networks with real-time response demands and scarce available resources. Furthermore, another main goal is the design and proposal of a respective network architecture aiming at optimum resource management under congestion scenarios and therefore maximization of network performance. Through various studies undertaken in the context of this dissertation the importance of the congestion problem is presented as a main factor leading the network to resource waste and saturation conditions negatively affecting all network performance metrics. Consequently, this dissertation aims in proposing a cross-layer architecture able to detect and tackle congestion phenomenon by dynamically retaining network performance at a steady state (as than is possible) where network performs optimally and resource waste in minimized. Among others, a main parameter is retaining compatibility with a wide range of widely used protocols of various layers as well compatibility concerning the coexistence in the same network of stations supporting with stations not supporting the proposed architecture. The proposed architecture is implemented in the context of widely known and used network simulator. Evaluation of this implementation through numerous simulations showed that the objectives are met since congestion phenomenon is tackled in most cases with significant benefits concerning network performance and resource management. Furthermore, due to the high parametrization degree it constitutes a very good base for future expansions.

The need for an Anthropocentric Development Evaluation stems from the inability of development theory and praxis, which has informed the past Development Decades, to ameliorate abject poverty experienced by most people throughout the world. Emanating from a hermeneutical-interpretist epistemology the fundamental argument of an Anthropocentric Development Evaluation is that people and the crucial aspects of their humanity should be the central focus in development and evaluation processes. Thus, taking the people-centred approach to development as its starting point, an Anthropocentric Development Evaluation draws attention to the marginalised, particularly the poor, the rural poor, resource-poor primary producers, women and their households. An Anthropocentric Development Evaluation also argues for an actor-orientation to Development Evaluation to emphasise the situational, yet individual behaviour, of people. Alongside such an approach, lies the significance of culture and people's knowledge for development, as well as the limitations, risks, uncertainties and vulnerabilities people face as a consequence of their humanity. These may influence the extent to which they participate in spontaneous or imposed development initiatives. An Anthropocentric Development Evaluation then comparatively assesses three sets of similar, yet different, methodologies using people and aspects of their humanity described above as the focus for that assessment. The methodologies assessed include Action Research, Social Impact Assessment and the Complementary Rural Development Field Tools. The purpose of doing so is to obtain a suitable medium through which to test the focus of an Anthropocentric Development Evaluation in a development setting. The testing of an Anthropocentric Development Evaluation in a development setting is done first by providing an Anthropocentric Development Evaluation of aspects of life of people living in the community of Nyanyadu in KwaZulu-Natal. Social Impact Assessments using the focus of an Anthropocentric Development Evaluation are then made of two development initiatives in respect of the people of Nyanyadu. These two initiatives are a nutrition and social development programme and the national land reforms. The purpose of all these evaluations is to examine the extent to which people and their humanity are seen to be crucial in development processes. / Development Administration / D.Litt. et Phil. (Development Administration)

The need for an Anthropocentric Development Evaluation stems from the inability of development theory and praxis, which has informed the past Development Decades, to ameliorate abject poverty experienced by most people throughout the world. Emanating from a hermeneutical-interpretist epistemology the fundamental argument of an Anthropocentric Development Evaluation is that people and the crucial aspects of their humanity should be the central focus in development and evaluation processes. Thus, taking the people-centred approach to development as its starting point, an Anthropocentric Development Evaluation draws attention to the marginalised, particularly the poor, the rural poor, resource-poor primary producers, women and their households. An Anthropocentric Development Evaluation also argues for an actor-orientation to Development Evaluation to emphasise the situational, yet individual behaviour, of people. Alongside such an approach, lies the significance of culture and people's knowledge for development, as well as the limitations, risks, uncertainties and vulnerabilities people face as a consequence of their humanity. These may influence the extent to which they participate in spontaneous or imposed development initiatives. An Anthropocentric Development Evaluation then comparatively assesses three sets of similar, yet different, methodologies using people and aspects of their humanity described above as the focus for that assessment. The methodologies assessed include Action Research, Social Impact Assessment and the Complementary Rural Development Field Tools. The purpose of doing so is to obtain a suitable medium through which to test the focus of an Anthropocentric Development Evaluation in a development setting. The testing of an Anthropocentric Development Evaluation in a development setting is done first by providing an Anthropocentric Development Evaluation of aspects of life of people living in the community of Nyanyadu in KwaZulu-Natal. Social Impact Assessments using the focus of an Anthropocentric Development Evaluation are then made of two development initiatives in respect of the people of Nyanyadu. These two initiatives are a nutrition and social development programme and the national land reforms. The purpose of all these evaluations is to examine the extent to which people and their humanity are seen to be crucial in development processes. / Development Administration / D.Litt. et Phil. (Development Administration)

Increasing tourism numbers in third world countries affect their economies and certain aspects of their society positively; however, there are concomitant negative effects that expose the dark side of the tourism industry. One of these is the escalating commercial sexual exploitation of children (CSEC), particularly child prostitution (CP) in the context of tourism, a phenomenon known as child sex tourism (CST). Although tourism plays an important role in creating the perfect storm of poverty-stricken children colliding with wealthy tourists, it is not solely responsible for this phenomenon. Internationally and nationally, the lacuna of knowledge on CST in particular hampers an informed response by way of resource allocation and coordinated service delivery to both victims and perpetrators. Utilising a qualitative research approach, and the collective case study and phenomenological research designs complemented by an explorative, descriptive and contextual strategy of inquiry, the researcher explored the status of the knowledge of and response to the CSEC through the lens of closely associated role players, who were purposively selected for inclusion in the study. These were adult survivors who were as children engaged in sex work and victims of child sex tourism, social workers and non-social workers involved in rendering child welfare and protection services, members of the Family Violence Child Protection and Sexual Offences (FCS) Unit of the South African Police Service (SAPS) and representatives of the hospitality and tourism industry. Data was collected via individual in-depth semi-structured interviews, telephone interviews, and email-communication and thematically analysed. The researcher found that a range of microsystem level factors, such as poverty and family dysfunction, pushed children to the street, and as a means to survive engage in sex work, enabling tourists (i.e. local - out of towners) and foreigners, mainly men from varied sexual orientation) to commercially sexually exploit both boys and girls, from as young as nine years of age, and of different race groups, which leave them with physical and psychological scars. The following main findings surfaced: The social workers, in comparison to the non-social workers, who have a primary responsibility to provide child welfare and protection services were ill-informed in terms of identifying CST as phenomenon, untrained and/or slow to respond appropriately with interventions directed to the victims and perpetrators of CSEC. The service provider groups, as microsystems interfacing on a mesosystem, were fraught with perceptions that the social workers and the SAPS were being inadequate. Furthermore a lack of cooperation, collaboration and communication between the service provider groups to respond to CSEC existed. The hospitality and tourism industry service representatives were also ill-informed about the phenomena of CP and CST with a response that at best can be labelled as fluctuating between an indirect response to that of turning a blind-eye. From the findings, recommendations for social work practice, education and training and recommendations specific for the other closely associated role players in responding to the CSEC were forwarded. / Social Work / D.Phil. (Social Work)

Increasing tourism numbers in third world countries affect their economies and certain aspects of their society positively; however, there are concomitant negative effects that expose the dark side of the tourism industry. One of these is the escalating commercial sexual exploitation of children (CSEC), particularly child prostitution (CP) in the context of tourism, a phenomenon known as child sex tourism (CST). Although tourism plays an important role in creating the perfect storm of poverty-stricken children colliding with wealthy tourists, it is not solely responsible for this phenomenon. Internationally and nationally, the lacuna of knowledge on CST in particular hampers an informed response by way of resource allocation and coordinated service delivery to both victims and perpetrators. Utilising a qualitative research approach, and the collective case study and phenomenological research designs complemented by an explorative, descriptive and contextual strategy of inquiry, the researcher explored the status of the knowledge of and response to the CSEC through the lens of closely associated role players, who were purposively selected for inclusion in the study. These were adult survivors who were as children engaged in sex work and victims of child sex tourism, social workers and non-social workers involved in rendering child welfare and protection services, members of the Family Violence Child Protection and Sexual Offences (FCS) Unit of the South African Police Service (SAPS) and representatives of the hospitality and tourism industry. Data was collected via individual in-depth semi-structured interviews, telephone interviews, and email-communication and thematically analysed. The researcher found that a range of microsystem level factors, such as poverty and family dysfunction, pushed children to the street, and as a means to survive engage in sex work, enabling tourists (i.e. local - out of towners) and foreigners, mainly men from varied sexual orientation) to commercially sexually exploit both boys and girls, from as young as nine years of age, and of different race groups, which leave them with physical and psychological scars. The following main findings surfaced: The social workers, in comparison to the non-social workers, who have a primary responsibility to provide child welfare and protection services were ill-informed in terms of identifying CST as phenomenon, untrained and/or slow to respond appropriately with interventions directed to the victims and perpetrators of CSEC. The service provider groups, as microsystems interfacing on a mesosystem, were fraught with perceptions that the social workers and the SAPS were being inadequate. Furthermore a lack of cooperation, collaboration and communication between the service provider groups to respond to CSEC existed. The hospitality and tourism industry service representatives were also ill-informed about the phenomena of CP and CST with a response that at best can be labelled as fluctuating between an indirect response to that of turning a blind-eye. From the findings, recommendations for social work practice, education and training and recommendations specific for the other closely associated role players in responding to the CSEC were forwarded. / Social Work / D. Phil. (Social Work)