M.A. (Psychology) / The concept of field dependence-field independence was developed by H.A. Witkin. Witkin and almost all subsequent researchers implicitly assumed that field dependence and field independence are bipolar opposites of a single underlying continuum. Resent research (O'Hara, 1985), however, suggested the possibility that field dependence and field independence are two independent constructs. The principal goal of the present study was to determine the cognitive and personality correlates of field dependence and field independence. To investigate the stated problem, a battery of 21 psychometric tests was administered to a stratified sample of 303 first year university students at the Rand Afrikaans University. The battery consisted of the newly constructed Field Dependence Inventory, Hidden Figures Test, Social Intelligence Test, Pattern Relations Test, and Jackson Personality Inventory. In order to ascertain whether the sample of students could be classified into (more than two) natural classes in terms of field dependence and field independence, a cluster analysis was performed. The Field Dependence Inventory served as a measure of field dependence, and the Hidden Figures Test, as a measure of field independence. These tests were used as input variables to the cluster analysis. Four classes were established. Differences in means between the four classes, in terms of the cognitive variables, were investigated by means of the Social Intelligence Test, and Pattern Relations Test. Personality differences were investigated by means of the Jackson Personality Inventory. The differences in means between the four classes, were investigated by means of a multivariate analysis of variance, one-way analyses of variance, and Scheffe's multiple comparisons...

Le nalméfène représente une option nouvelle dans le traitement de l’alcoolodépendance. Cette molécule a reçu une AMM européenne en 2013 pour réduire la consommation d’alcool des patients adultes ayant une consommation à risque élevé selon la classification de l’OMS (i.e. plus de 60 g d'alcool par jour pour les hommes, ou plus de 40 g par jour pour les femmes). Toutefois, les avis dans la littérature divergent quant à son intérêt. Nous avons donc souhaité réévaluer le rapport bénéfice-risque de cette molécule en appliquant des méthodes appartenant au domaine de la méta-recherche. Une première méta-analyse des essais randomisés contrôlés comparant le nalméfène par voie orale à un placebo nous a permis de mettre en évidence des tailles d’effet faibles sur les critères de consommation, avec un possible biais d’attrition dans les études. Dans une seconde méta-analyse en réseau évaluant l’efficacité, dans l’indication de réduction des consommations, du nalméfène à d’autres traitements également utilisés dans la prise en charge de l’alcoolodépendance, nous avons conclu à l’absence de preuve de haut niveau de l’efficacité des traitements pharmacologiques pour contrôler la consommation d'alcool chez les patients non abstinents souffrant de troubles liés à l’usage. Enfin, nous avons montré, à travers la réalisation d’un grand nombre de méta analyses, que les choix méthodologiques faits dans les essais randomisés contrôlés évaluant le nalméfène et la naltrexone dans la prise en charge de l’addiction à l’alcool entraînaient une variation substantielle de l’estimation de l’efficacité de ces deux traitements, phénomène également appelé « vibration de l’effet » des traitements. / Nalmefene is a new option in the treatment of alcohol dependence. It was approved by the European Medicines Agency to help reduce alcohol consumption in adults who consume more than 60 g of alcohol per day (for men) or more than 40 g per day (for women). However, researchers’ opinions on the interest of the drug are divided. We therefore planned direct and network meta-analyses to enable an objective reappraisal of the efficacy of nalmefene. A first meta-analysis of randomized controlled trials comparing oral nalmefene with placebo showed small effect sizes on consumption criteria with a possible attrition bias in the studies. In a second network meta-analysis evaluating the comparative efficacy of nalmefene to control drinking with other treatments also used in the management of alcohol dependence, we concluded that there was no high-grade evidence for pharmacological treatment to control drinking in non-abstinent patients with alcohol use disorders. Finally, we explored the vibration of effects in a large number of overlapping indirect meta-analyses comparing nalmefene versus naltrexone to reduce alcohol consumption. We demonstrated that the methodological choices made in randomized controlled trials resulted in a substantial variation in the effect sizes of these two treatments.

The resolution of spatial data has increased over the past decade making them more accurate in depicting landform features. From using a 60m resolution Landsat imagery to resolution close to a meter provided by data from Unmanned Aerial Systems, the number of pixels per area has increased drastically. Topographic features derived from high resolution remote sensing is relevant to measuring agricultural yield. However, conventional algorithms in Geographic Information Systems (GIS) used for processing digital elevation models (DEM) have severe limitations. Typically, 3-by-3 window sizes are used for evaluating the slope, aspect and curvature. Since this window size is very small compared to the resolution of the DEM, they are mostly resampled to a lower resolution to match the size of typical topographic features and decrease processing overheads. This results in low accuracy and limits the predictive ability of any model using such DEM data. In this dissertation, the landform attributes were derived over multiple scales using the concept of sliding window-based aggregation. Using aggregates from previous iteration increases the efficiency from linear to logarithmic thereby addressing scalability issues. The usefulness of DEM-derived topographic features within Random Forest models that predict agricultural yield was examined. The model utilized these derived topographic features and achieved the highest accuracy of 95.31% in predicting Normalized Difference Vegetation Index (NDVI) compared to a 51.89% for window size 3-by-3 in the conventional method. The efficacy of partial dependence plots (PDP) in terms of interpretability was also assessed. This aggregation methodology could serve as a suitable replacement for conventional landform evaluation techniques which mostly rely on reducing the DEM data to a lower resolution prior to data processing. / National Science Foundation (Award OIA-1355466)

The purpose of this dissertation is to examine aspects of the representational and computational influences on Bayesian reasoning as they relate to reference dependence. Across three studies, I explored how dependence on the initial problem structure influences the ability to solve Bayesian reasoning tasks. Congruence between the problem and question of interest, response errors, and individual differences in numerical abilities was assessed. The most consistent and surprising finding in all three experiments was that people were much more likely to utilize the superordinate value as part of their solution rather than the anticipated reference class values. This resulted in a weakened effect of congruence, with relatively low accuracy even in congruent conditions, as well as a different pattern of response errors than what was anticipated. There was consistent and strong evidence of a value selection bias in that incorrect responses almost always conformed to values that were provided in the problem rather than errors related to computation. The one notable exception occurred when no organizing information was available in the problem, other than the instruction to consider a sample of the same size as that in the problem. In that case, participants were most apt to sum all of the subsets of the sample to yield the size of the original sample (N). In all three experiments, higher numerical skills were generally associated with higher accuracy, whether calculations were required or not.

For selected YAG:Ce sample the temperature dependent absorbtion and emission spectra were measured and used to simulate white LED behavior. Various CIE-xy dependencies were observed. Sample surface scaterring parameters were calibrated using a custom-made automated goniospektrometer, which provided measured data with fine accuracy. Finally, the measured data were used to construct a Geant4 simulation to optimize two light devices for output intensity and target CIE-xy coordinates. Powered by TCPDF (www.tcpdf.org)

Ontic structural realism is the view that structure is fundamental. This view is at odds with a long-standing tradition in metaphysics which takes the fundamental structure of reality to consist of individuals. Steven French argues in favour of an eliminativist ontic structural realism which is supposed to eliminate individuals, as well as other objects, from the category of fundamentalia. There have also been more moderate attempts where 'non-individuals' are encompassed in the framework. In this paper, I make two interconnected claims. Firstly, that any moderate version of ontic structural realism is too weak to be included in the ontic structural realism familiy since the view fails to satisfy the motivations for employing any kind of ontic structural realism in the first place. Secondly, that if we want to formulate an ontic structural realist view that delivers on the claim that there are no fundamentalia apart from structure we will not find a satisfying view in French's oeuvre.

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Magister Curationis - MCur / Research reported that it is very challenging for mental health care users to quit smoking and the risk of relapsing after quitting is high. However, tobacco dependence treatment is possible and potentially lifesaving for people. The delivery of tobacco dependence treatment by nurses is influenced by a variety of factors, including lack of knowledge and skills, limited professional leadership, and smoking within the profession. There is a strong link between mental illness and smoking-related diseases, including cancer, respiratory diseases and heart diseases that are linked with depression. There is a high incidence of cancer in people with bipolar mood disorder and schizophrenia due to smoking. In spite of this, smoking is regarded as part of the culture of psychiatric institutions and tobacco is seen as “necessary self- medication for the mentally ill”.

Substance abuse and dependence are globally contested issues. In a volatile space, the field is undergoing major changes in terms of decriminalisation and reduction of harm efforts in numerous countries. Despite continued efforts to minimise or even eradicate substance use and abuse, recovery programmes still lack sustainability. Relapse is still common, and there is little in the way of literature explaining how some individuals manage successful sustained recovery. Although the field is undergoing many changes, it appears obvious that society still lacks adequate research and information to guide and motivate sustainable recovery. Family systems are generally experienced as a person’s primary system, and it may be assumed that many people become dependent on their family or family members for varying degrees of support. Systems theory underpinned this qualitative case study, comprising multiple cases, in order to explore the experience of individuals who expressed an interest in their own recovery and, more specifically, to discover whether they viewed family support as an assistive factor in this decision. The study found that although family support did not motivate recovery, it was nevertheless an important factor in continued efforts toward recovery once the individual had made their own decision to commence a recovery programme. / Dissertation (MA)--University of Pretoria, 2019. / Psychology / MA Psychology / Unrestricted

Family, twin, and adoption studies have indicated that genetic and environmental factors contribute to the development of alcohol dependence (AD). We conducted a low-density genome-wide association analysis to identify genetic variants influencing AD. We used 11,120 SNPs from the Affymetrix 10K Genechips genotyped in 116 Caucasian pedigrees (272 nuclear families) from Genetic Analysis Workshop 14, a subset from the Collaborative Study on the Genetics of Alcoholism (COGA). Family-based association analyses for AD were performed by the PBAT program for autosomal SNPs and by the FBAT program for X-chromosome SNPs. We identified 37 SNPs associated with AD (P < 10 -3), thirteen of which were located in known genes. The most significant association with AD was observed with SNP rs1986644 (P = 8.51 × 10 -6) at 13q22 near EDNRB gene. The next best signal was at 1q41 in USH2A (rs532342, P = 1.07 × 10 -5) and the third region was at 3q25.31 in TIPARP (rs1367311, P = 2.31 × 10 -5). Furthermore, we found support for association of MAOA gene (P = 4.14 × 10 -4 for rs979606). Six of the 37 AD associated SNPs were confirmed to be associated with AD in Australian twin-family study sample (P < 0.05). Interestingly, four SNPs in DSCAML1 at 11q23 reached the genome-wide significance (the top SNP is rs10892169 with P = 5.31 × 10 -9), while rs637547 in NKAIN2 at 6q21 showed strong association with AD (P = 5.11 × 10 -7) in the replication sample. These findings offer the potential for new insights into the pathogenesis of AD and will serve as a resource for replication in other populations to elucidate the potential role of these genetic variants in AD.