abstract: A key factor in the success of social animals is their organization of work. Mathematical models have been instrumental in unraveling how simple, individual-based rules can generate collective patterns via self-organization. However, existing models offer limited insights into how these patterns are shaped by behavioral differences within groups, in part because they focus on analyzing specific rules rather than general mechanisms that can explain behavior at the individual-level. My work argues for a more principled approach that focuses on the question of how individuals make decisions in costly environments. In Chapters 2 and 3, I demonstrate how this approach provides novel insights into factors that shape the flexibility and robustness of task organization in harvester ant colonies (Pogonomyrmex barbatus). My results show that the degree to which colonies can respond to work in fluctuating environments depends on how individuals weigh the costs of activity and update their behavior in response to social information. In Chapter 4, I introduce a mathematical framework to study the emergence of collective organization in heterogenous groups. My approach, which is based on the theory of multi-agent systems, focuses on myopic agents whose behavior emerges out of an independent valuation of alternative choices in a given work environment. The product of this dynamic is an equilibrium organization in which agents perform different tasks (or abstain from work) with an analytically defined set of threshold probabilities. The framework is minimally developed, but can be extended to include other factors known to affect task decisions including individual experience and social facilitation. This research contributes a novel approach to developing (and analyzing) models of task organization that can be applied in a broader range of contexts where animals cooperate. / Dissertation/Thesis / Doctoral Dissertation Applied Mathematics for the Life and Social Sciences 2016

The effects associated with foreign direct investments onto a host economy are perceived to be multi folded. FDI is perceived to enhance, not only, the accumulation of capital in a host country, but also to promote productivity, enable introduction of new processes and skills as well as enable access to new markets. However, empirical research upon if foreign direct investments affects economic growth is ambiguous. The purpose of this thesis is due to such to investigate whether the local financial market enable FDI to affect growth positively. Hence, the aim of this paper is to establish if the domestic financial sector is a vital precondition for foreign direct investment to have a positive significant effect on GDP per capita growth for developing countries. By the use of panel data regressions and three regression models, 26 countries were investigated between the years 1996 and 2015. The empirical results enabled the conclusion that local financial markets do in fact improve the effect associated with foreign direct investment for the 26 countries investigated between the years 1996 and 2015. Thus, local financial markets are a significant and crucial precondition for FDI to affect a host economy's growth positively. Due to such, developing countries should aim towards preserving as well as developing their financial markets.

Background: Low back pain (LBP) is the leading cause of disability and is often accompanied with a back-related leg pain (around 60%), where those with radiating pain show worse overall clinical outcomes. Previous studies comparing these two groups have involved individuals with chronic LBP. It is not known if subjects who currently have LBP differ in pain sensitivity from those who have currently LBP accompanied with pain radiation to lower limbs. Aim: The aim of this study was to investigate whether there are differences in self-reported health and pain sensitivity between individuals currently having LBP with and without pain radiation to lower limbs. Method: Individuals with LBP (n=100) aged 40 to 70 years participated in this study. According the first question of STarT Back Pain Screening Tool about the pain radiation to leg(s), individuals were divided into two groups: radiation group (RG, n=36) and no radiation group (noRG, n=64). To gain the information about self-reported health, following questionnaires were used: Roland-Morris Disability Questionnaire, Fear-Avoidance Beliefs Questionnaire and Hospital Anxiety and Depression Scale. Pressure pain thresholds (PPTs) were measured with algometer (6 sites and 4 points of ’lower body’: gluteal and knee points). Mann-Whitney U-test was used to calculate differences on group and gender level. A logistic regression analyses was calculated (crude model), where belong to RG or not was the dependent variable and all self-reported data and PPTs were independent variables, all data were controlled for gender and age. Results: The RG reported worse disability (p=0.017), higher fear-avoidance beliefs (FAB) about physical activity (p=0.003), worse score in anxiety (p=0.002) and depression (p=0.001), and increased pain sensitivity (p=0.043) in 6 sites PPTs compared to the noRG. Higher score of disability, FAB (physical activity and work), anxiety and depression were associated with an increased risk of belonging to the RG (OR 1.05-1.50, 95% CI 1.01-1.94), controlled for gender and age. Conclusion: Individuals with LBP and pain radiation to lower limbs showed worse self-reported disability and fear-avoidance beliefs about physical activity than those with LBP only. Further, those with pain radiation were more sensitive to pain in general. Worse scores of all studied self-reported data were associated with an increased risk of belonging to the groups with pain radiation. To study gender differences larger sample sizes are needed. Individuals with LBP and pain radiation to lower limbs showed worse outcomes and therefore should receive a different treatment approach than those who have only LBP.

A abdominoplastia é uma das cirurgias plásticas mais realizadas. A associação entre a lipoaspiração e o descolamento reduzido trouxe uma nova perspectiva em relação à maior preservação da inervação cutânea sensitiva. Novos métodos de avaliação de sensibilidade têm permitido melhor quantificação e uma análise mais completa da evolução pós-operatória. Foi realizado um estudo do tipo caso-controle comparando-se um grupo controle de pacientes não operadas, um grupo de pacientes que realizou abdominoplastia convencional e um grupo que realizou abdominoplastia associada a lipoaspiração e descolamento reduzido. Para a avaliação da sensibilidade, utilizou-se o PSSD (dispositivo específico de sensibilidade de pressão), testes para sensibilidade térmica e dolorosa (agulhas). O PSSD foi aplicado em nove regiões da parede abdominal anterior para determinação do limiar cutâneo de pressão (LCP) em duas modalidades sensoriais: um ponto estático (1PE), para avaliação de fibras de adaptação lenta, e um teste dinâmico (1PD), para avaliação de fibras de adaptação rápida. Quanto maior o LCP, menor a sensibilidade na região. Foram incluídas 46 pacientes nos três grupos. O grupo controle continha 10 pacientes, cujos limiares cutâneos de pressão (LCP) variaram de 0,82 a 0,84 e de 0,77 a 0,79 g/mm2 para 1PE e 1PD, respectivamente. O grupo de abdominoplastia convencional (AC) continha 14 pacientes com medidas em dois momentos de pós-operatório, precoce (5,75 meses) e tardio (17,36 meses). Os resultados demonstraram LCPs entre 1,02 e 39,94 para a medida precoce e 0,79 e 20,07 g/mm2 para a medida tardia. O grupo de abdominoplastia associada a lipoaspiração (LA) continha 22 pacientes com acompanhamento de 5,72 meses (precoce) e 14,91 meses (tardio). Os resultados demonstraram LCPs entre 0,62 e 4,98 para a medida precoce e 0,67 e 1,91 g/mm2 para a medida tardia. A análise estatística usou método de análise de variância com medidas repetidas. O nível de significância adotado foi de 0,05. A análise estatística para a medida de 1PE revelou redução da sensibilidade significante no grupo AC em todas as regiões (precoce e tardia). No grupo LA, houve redução da sensibilidade apenas nas regiões de mesogastro e hipogastro na medida precoce com regularização total na análise tardia. Entretanto, a análise estatística para 1PD revelou, no grupo AC, redução na medida precoce em todas as regiões e redução apenas das regiões centrais (mesogastro e hipogastro) na análise tardia. Já no grupo LA, todas as medidas estavam normalizadas na análise precoce e tardia. A análise da sensibilidade térmica e dolorosa revelou reduções centrais, especialmente nas regiões de mesogastro e hipogastro no grupo AC. O grupo LA revelou áreas de anestesia térmica e dolorosa apenas em pequena área do hipogastro. Concluiu-se que as três modalidades sensoriais (tátil, térmica e dolorosa) são mais preservadas no grupo LA que no grupo AC. A recuperação da medida 1PD é mais rápida que a medida de 1PE / Abdominoplasties are common plastic surgery procedures. New techniques associating lipoaspiration with selective undermining are bringing new perspectives with regard to the preservation of cutaneous sensibility. New methods of evaluation of cutaneous sensibility have allowed researchers to do a more complete analysis. This is a case-control study comparing a control group of patients non operated with one group submitted to conventional abdominoplasty and another group submitted to abdominoplasty associating lipoaspiration with selective undermining. The abdominal surface was divided into nine regions for sensibility evaluation. Superficial tactile sensibility was tested using the Pressure Specified Sensory Device (PSSD) which allows the determination of the cutaneous pressure threshold (static and moving). Tests of pain and thermal sensibility were also performed. A total of 46 patients were divided in three groups. In the control group, with 10 patients, the cutaneous pressure thershold (CPT) oscilated from 0.82 to 0.84 and from 0.77 to 0.79 g/mm2 for one point static and one point moving sensibility evaluations, respectively. The group of patients submitted to conventional abdominoplasty (AC), with 14 patients, was evaluated in two moments of follow-up: early (mean of 5.75 months after surgical procedure) and late (17.36 months). The results showed CPTs betwen 1.02 and 39.94 in the early follow-up, versus 0.79 to 20.07 g/mm2 in the late follow-up. The group submitted to abdominoplasty associated with lipoaspiration and selective underminig (LA) had 22 patients, with a mean follow-up period of 5.75 (early) and 14.91 (late) months. The results showed CPTs betwen 0.62 and 4.98 (early) and 0.67 and 1.91 g/mm2 (late). The statistical analysis was conducted with the analysis of variance with repeated measurements. The level of significance adopted was p < 0.05. The estatistical analysis for one point static showed significant reduction of sensibility in the group AC in all abdominal regions (in the early and late follow-up periods). The group LA presented reduced CPT only in the mesogastric and hypogastric in the early evaluation; the late evaluation was normal. On the other hand, the analisis of one point moving showed, in the group AC, a reduction of early evaluation measurement in all abdominal regions and a reduction only in central regions (mesogastric and hypogastric) in the late. The LA group presented normal in all measurements. The analysis of pain and thermal sensibility shows that the centermost regions of the abdomen, mesogastric and hypogastric, presented the highest anesthesia index in the AC group. The LA group showed just some islands in the hipogastric regions. The recuperation of the 1PD evaluation was faster than the 1PE. In conclusion, the three sensibilities (tactile, thermal and pain) were more preservated in the LA group. Abdominoplasty with lipoaspiration could be considered a better choice than conventional abdominoplasty considering the preservation of cutaneous sensibility

Skin temperature is detected through signals in unmyelinated C-fibers and thin myelinated Aδ-fibers in the peripheral and central nervous system. Disorders in thin nerve fibres are important and not rare but difficult to diagnose by the most common neurophysiological methods. In this pilot study different methods for quantitative sensory testing, QST, were compared to give some ideas about which method could be the most efficient to use in order to point out injuries of the sensory system in clinical practice. The comparison was made between Békésy (separate warmand cold thresholds) and Marstock test (combined warm and cold thresholds). The study also included the test persons estimations of the difficulty to perform the tests. The study showed that there was no practical difference between the tests and that the test persons estimations did not show any indications that the methods differed in rating of difficulty. Our study did not give reason to stop measuring warm and cold detection thresholds separately, which is the international standard and have some theoretical advantages. We also compared detection thresholds for hand and foot, warmth and cold and for both slow and fast temperature changes to enlighten factors that could affect our measuring data.

>Magister Scientiae - MSc / There is a high incidence of dropout in the first year of university studies. Some of the main reasons were attributed to adjustment or adaptation difficulties experienced by the new students which impacted on academic achievement. Much of this difficulty relates to the need to find their identity in relation to the new university environment with new rules, peers, and expectations. The acquisition of a sensory integrative (SI) profile could shed light on an element of the student’s identity. However, very little is known about the relationship between the SI profile and academic achievement. Therefore, the aim of the study was to determine the SI profiles of students and whether there was a relationship between the SI profiles and academic achievement of first year students from the Faculty of the Community and Health Sciences (FCHS) at the University of the Western Cape (UWC).The study followed the quantitative research paradigm and was more specifically a descriptive, cross-sectional study. Measurements included a demographic questionnaire to gather socio-demographic data, as well as the Adolescent and Adult Sensory Profile questionnaire to determine the SI profiles of the students.These instruments were administered to a sample of 357 registered first year students from the FCHS at UWC. Matriculation academic marks, as well as first year university academic marks were obtained and utilised for analysis. The SPSS statistical package was utilised for descriptive and inferential statistical analyses of the data. The results of the study indicated that the SI profiles of the first year FCHS students were that they responded "similarly to most people" on each of the four sensory quadrants of Dunn's (1997) Model of Sensory Processing. Secondary analyses were implemented by means of a collapsing mechanism to denote more specific results of the SI profiles. This analysis revealed that the students tended to have low thresholds for their neurological and behavioural continua of sensory processing.The inferential analyses that were implemented to determine whether there was a relationship between the SI profiles and academic achievement of the first year students yielded no statistical relationship between those variables. The analyses revealed relationships between the SI profiles and certain socio-demographic factors, such as age, race, and course of study.In conclusion, the research study uncovered the SI profiles of the first year university student sample, relationships between the SI profiles and sociodemographics and disproved a relationship between SI profiles and academic achievement. The study was therefore of value to the professions of occupational therapy and higher education and has opened avenues for further exploration. Furthermore the study has portrayed that occupational therapy tools and SI profiles could have a place in higher education and in relation to student development, teaching and learning. / National Research Foundation (NRF)

Multiple-criteria decision-making (MCDM) is a field of decision theory concerned with analyzing discrete sets of variables evaluated by multiple criteria. Facilitating decisions in such situations are several methods, among them a family known as ELECTRE. Using threshold values and the concept of outranking, they allow for improved modeling of the uncertain nature of real systems. This thesis sets out to describe all of the basic ELECTRE methods, as well as several of their modifications and further extensions and aims to do so with a sufficient level of detail and using precise mathematical language. It also presents key applications of said methods and reviews their implementation in software. Lastly, it introduces a brand new software, ELIA, developed as a part of the thesis. It allows users to solve practical problems using four of the basic ELECTRE methods.

Orientador: José Augusto Lollo / Resumo: A erosão é um fenômeno complexo, uma vez que envolve a ação direta ou indireta de diversos fatores, tais como tipos de solos, clima, vegetação, declividade e ações antrópicas. O estudo acerca da dinâmica, agentes desencadeadores e fatores condicionantes é uma importante ferramenta para uma tomada de decisão. A proposição de índices que indicam o limiar crítico para determinar a ocorrência de processos erosivos, é uma das vertentes dos estudos acerca de processos erosivos, cuja pressupõe-se uma relação entre a declividade (S) e área de contribuição (A), que condiciona os processos de erosão. Considerando os avanços na geração dos produtos de Sensoriamento Remoto, este trabalho objetivou realizar um estudo sobre o desencadeamento das erosões lineares, no qual propõe a avaliação da empregabilidade do Modelo Digital de Elevação (MDE) gerado por meio de imagem de radar interferométrico (ALOS/Palsar) para obtenção dos parâmetros topográficos da Bacia Hidrográfica do Rio Bonito, inserida no município de Descalvado e Porto Ferreira no estado de São Paulo. Com isso o MDE, o mapa de declividades e direção de fluxo foram elaborados em ambiente SIG, com pixels de saída de 2m, possibilitando obter os valores de A versus S, utilizando o algoritmo D-Infinity para o processamento dos dados hidrológicos. Os valores obtidos forma representados em um gráfico, permitindo identificar a declividade mínima para a ocorrência de um processo erosivo, bem como estabelecer de forma empírica o limiar top... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Erosion is a complex phenomenon as it involves the direct or indirect action of various factors such as soil types, climate, vegetation, slope and anthropic actions. The study about dynamics, triggering agents and conditioning factors is an important tool for decision making. The proposition of indices that indicate the critical threshold to determine the occurrence of erosive processes is one of the strands of studies on erosive processes, whose assumption is a relationship between slope (S) and contribution area (A), which conditions the erosion processes. Considering the advances in the generation of Remote Sensing products, this work aimed to conduct a study on the triggering of linear erosions, which proposes the evaluation of the employability of the Digital Elevation Model (MDE) generated by interferometric radar imaging (ALOS / Palsar) to obtain the topographic parameters of the Bonito River Watershed, inserted in the municipality of Descalvado and Porto Ferreira in the state of São Paulo. With this the MDE, the slope map and flow direction were elaborated in GIS environment, with 2m output pixels, allowing to obtain the values of A versus S, using the D-Infinity algorithm for the hydrological data processing. The values obtained were represented in a graph, allowing to identify the minimum slope for the occurrence of an erosive process, as well as to establish empirically the topographic threshold. The index obtained in this work from the analysis was S = 0.0333A-0.0... (Complete abstract click electronic access below) / Mestre

Studies on taste perception in nonhuman primates contribute to the understanding of the evolution of the sense of taste. To assess the responsiveness of four adult spider monkeys (Ateles geoffroyi) to a set of substances perceived as sweet by humans, two-bottle preference tests were performed to determine taste preference thresholds, and taste-induced facial responses were analyzed. The spider monkeys displayed a significant preference for concentrations as low as 0.2-1 mM acesulfame K, 0.002-0.5 mM alitame, 10-20 mM isomalt, 0.002-0.5 mM sodium saccharin, 2-20 mM galactose and 20-50 mM sorbitol over water. The spider monkeys were generally unable to perceive aspartame and, based on their facial responses, probably do not perceive it as sweet. Thaumatin and monellin were not detected, and most likely neither was the sweetness of sodium cyclamate. Sodium saccharine and sodium cyclamate were rejected at high concentrations by at least one monkey, which is congruent with the perception of a bitter side taste as reported in humans. A significant correlation was found between the ranking order of sweetening potency for the different substances of spider monkeys and humans, but not between spider monkeys and chimpanzees. The results suggest that spider monkeys may be generally more sensitive than chimpanzees and at least as sensitive as humans to the tested substances, supporting the notion that high sensitivity to sweet taste may be associated with a frugivorous dietary specialization. The lack of responsiveness to some of the substances supports the notion of a dichotomy in sweet-taste perception between platyrrhine and catarrhine primates.

Masking Level Difference (MLD) tests are an established component of auditory processing test batteries; however, normative data for these tests vary according to procedure. In this study, forty normal, native-English speaking adults between the ages of 18 and 26 were tested for MLD via a newly developed computer software program using both an adaptive procedure (MLDA) and a Bekesy procedure (MLDB). The results from the two procedures were analyzed for sex differences and compared with each other. For both the MLDA and MLDB, the results showed statistically significant sex differences in the masked thresholds used to obtain the MLD (NoSo and NoSπ), but no significant difference in the calculated MLD value (NoSo - NoSπ). These results suggest that since the MLD was similar for both sexes, the normative data need not be reported separately by sex. The results also showed statistically significant differences between procedures, with the MLDA procedure producing higher MLDs than the MLDB procedure. The MLDA procedure lent itself to a d´ analysis, which could not be determined using MLDB due to the nature of a Bekesy assessment. For MLDA, d´ = 1.4, test sensitivity = 96.4%, and test specificity = 60.3%. The results of this study indicate that MLDA is a better testing procedure due to MLDA's higher MLD average and the statistical data available (d´, and measures of sensitivity and specificity) when using the MLDA procedure.