Esta tese de doutorado aborda o desenvolvimento de sistemas microfluídicos eletroquímicos ultrassensíveis mediante a integração de eletrodos i) concêntricos e ii) nanoestruturados seletivos à detecção condutométrica sem contato acoplada capacitivamente (capacitively coupled contactless conductivity detection, C4D) e à amperometria, respectivamente. O uso dos eletrodos concêntricos, uma configuração inédita em microdispositivos na qual o filme fino metálico circunda todo o microcanal, se mostrou efetivo na melhora da detectabilidade da C4D para análises em fluxo de soluções padrão de LiClO4. O limite de detecção (LD) para esse sal foi igual a 343 pmol L-1, um valor aproximadamente quatro ordens de grandeza inferior àquele obtido com eletrodos planares. O microchip amperométrico nanoestruturado, por sua vez, consistiu de filmes de Au modificados com nanotubos de carbono de parede única (single-walled carbon nanotubes, SWCNTs) verticalmente alinhados e foi aplicado a padrões do neurotransmissor serotonina. A melhora na detectabilidade do método foi novamente apreciável; os valores de LD foram de 11,8 (Au liso) e 0,2 nmol L-1 (Au modificado com os SWCNTs verticalmente alinhados). Esse último é menor frente à grande maioria dos valores descritos na literatura, para os quais técnicas diversas foram empregadas, incluindo: i) potenciometria com eletrodos modificados (1,0 a 500 nmol L-1), ii) HPLC-MS (18,2 nmol L-1), iii) eletroforese capilar combinada com etapas de extração, empilhamento e préconcentração do analito (7,9 nmol L-1) e iv) sensor químico (200 nmol L-1). Finalmente, objetivando a fabricação de microchips de vidro, condutométricos e amperométricos, incorporando eletrodos concêntricos nanoestrurados, uma nova técnica de selagem foi desenvolvida. Essa técnica, designada como selagem adesiva de sacrifício, baseia-se no uso do resiste negativo SU-8 como camada intermediária de modo a permitir a vedação entre duas lâminas de vidro. Numa etapa posterior, a remoção seletiva do SU-8 sob o microcanal é realizada. Logo, canais microfluídicos com propriedades de superfície similares às do vidro foram obtidos. O protocolo experimental adotado é i) simples, ii) rápido, iii) não envolve níveis de pressão e temperatura elevados e iv) prescinde o uso de salas \"limpas\". Vedações com forças de adesão satisfatórias foram alcançadas, suportando pressões superiores a 4 MPa. / This PhD thesis reports the development of ultrasensitive electrochemical microfluidic systems by integrating concentric and nanostructured electrodes selective to capacitively coupled contactless conductivity detection (C4D) and amperometry, respectively. The use of the concentric electrodes, a new assembly in microdevices with thin films wrapping around the microchannel, showed to be effective towards improvement of the detectability in pressure-driven flow platforms incorporating C4D. The limit-of-detection (LOD) in flow analysis of LiClO4 solutions was 343 pmol L-1, ca. four orders of magnitude lower than to the levels obtained with planar electrodes alone. The nanostructured amperometric microchip, in turn, is related to integration of vertically aligned singlewalled carbon nanotubes (SWCNTs) over Au film. Such platform was applied to determination of serotonin standards. The nanomaterial influenced remarkably the sensitivity and detectability. Our system achieved a LOD of 0.2 nmol L-1, to the best of our knowledge one of the lowest values reported in the literature. Finally, in order to fabricate glass microdevices, conductometric and amperometric, with nanostructured concentric electrodes, we developed a new bonding method. This technique, called as sacrificial adhesive bonding, is based on SU-8 negative resist like intermediate layer so to allow the sealing between two glass slides. Next, the selective removal of the SU-8 under the microchannel is carried out. Thus, microfluidic channels presenting glass-like surface properties were achieved. The experimental protocol is simple and fast. In addition, neither high-pressure and elevated-temperature nor the use of \"clean\" rooms were not required. Bondings with satisfactory adhesion forces were obtained, supporting pressures above 4 MPa.

Objetivo: Avaliar a Função de Sensibilidade ao Contraste de Luminância Espacial e Temporal, estudar o desenvolvimento destas funções, a contribuição das vias de processamento paralelo para as funções de Sensibilidade ao Contraste e seu respectivo desenvolvimento e, por fim, determinar valores normativos destas funções visando uma aplicabilidade clínica.Método A avaliação psicofísica de sensibilidade ao contraste de luminância espacial e temporal foi realizada em 112 sujeitos divididos em três grupos:GrupoI ( idade média =9,14±2,7 anos),Grupo II ( idade média=23,7 ± 3,4 anos) e Grupo III ( idade média=41,8± 5,5 anos) com o programa PSYCHO for Windows Versão 2.36 (Cambridge Research Systems, CRS-Ltd, UK) acoplado a um microcomputador PC XTC -600. . Os estímulos foram apresentados em um monitor Sony Triniton de 19 polegadas GFD420 (Sony Corporation, USA) com resolução espacial de 800X600 e resolução temporal de 69 Hz Os estímulos eram comandados pela placa gráfica VSG 2/4 (Cambridge Research Systems, CRS-Ltd, UK).Resultados A avaliação psicofísica para a sensibilidade ao contraste espacial e temporal mostraram que esta função já está desenvolvida e em pleno funcionamento em crianças (6 anos) ocorrendo um declínio para as frequências espaciais de 2,0cpg;8,3cpg e 14,5cpg para os grupos II e III.Para a frequência temporal de 2,5Hz o declínio ocorre nos Grupos II e III e para a frequência temporal de 5,0 Hz nas idades mais avançadas(GIII). Para o estudo da contribuição das vias de processamento paralelo (magnocelular e parvocelular) podemos notar uma maior sensibilidade ao contraste para decremento de luz do que para incremento de luz, porém não foi possível determinar a real contribuição dessas vias para a função de sensibilidade ao contraste. Conclusão Avaliamos com sucesso a Sensibilidade ao Contraste Espacial e Temporal para todas as faixas etárias e, assim, conseguimos ter acesso ao desenvolvimento desta função, entre as idades de 6 e 57 anos. Valores normativos para as tais funções foram estabelecidos por metodologia nãoparamétrica.. O estudo da contribuição das vias magnocelular e parvocelular não pode ser conclusivo, porém os achados mostraram uma maior sensibilidade para o decremente de luz o que corrobora com a literatura / Purpose: To analyze the spatial and temporal luminance contrast sensitivity function, to study the development of these functions, the contribution of the parallel processing pathways and to determine the normative values of these functions to order a clinical applicability normative. Methods the psychophysical evaluation of the spatial and temporal luminance contrast sensitivity was performed in 112 subjects divided into three groups: Group I (mean age =9.14±2.7 years), Group II (mean age=23.7 ± 3.4 years) and Group III (mean age=41.8± 5.5 years) with the PSYCHO for Windows Version 2.36 (Cambridge Research Systems, CRS-Ltd, UK) connect to the microcomputer PC XTC -600. The stimuli was showed in a monitor Sony Triniton de 19 inches GFD420 (Sony Corporation, USA) with spatial resolution of the 800X600 and temporal resolution of the 69 Hz. The stimuli was made by the graphics card VSG 2/4 (Cambridge Research Systems, CRS-Ltd, UK).Results The psychophysics evaluation to spatial and temporal contrast sensitivity showed that this function is already developed and full operation in children (6 years old) with a decline to spatial frequencies of 2.0cpg;8.3cpg and 14.5 cpg to the groups II and III. For the temporal frequency of 2.5Hz the decline occur to the groups II and III .and to the temporal frequency of 5.0 Hz the decline occur to the advantage ages(GIII). For the study of the parallel processing pathways (magnocellular e parvocellular) we can see bigger contrast sensitivity to decrement than to increment of light. It was not possible determine the real contribution of these pathways to the contrast sensitivity function. Conclusion We evaluated in a successful way the spatial and temporal contrast sensitivity to all age range and so we could access the development of this function between the ages from 6 to 57 years old. Normatives values to this function were established for non parametric methodology. The study of the contribution of the parvocellular and magnocellular pathways is not conclusive, but the results showed a bigger sensibility to decrement than to increment of light that was similar to the literature

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A opacificação do cristalino presente ao nascimento ou nos primeiros meses de vida é denominada de Catarata Congênita (CC). As primeiras semanas de vida são importantes no desenvolvimento visual, já que há diferença significativa no desempenho visual de crianças que passaram pela cirurgia até seis semanas de vida (com melhor desempenho visual) em relação às crianças que realizaram a cirurgia após seis semanas de vida. Crianças que tiveram privação visual durante a primeira infância por catarata bilateral apresentam redução da visão espacial. O objetivo deste trabalho foi verificar o impacto na Função de Sensibilidade ao Contraste (FSC) em crianças de tratamento cirúrgico de Catarata Congênita, durante a fase de desenvolvimento visual. Foram avaliados três grupos: 11 crianças do grupo controle (média idade =6,83; DP=1,38), 9 crianças do grupo CC (média idade =6,87; DP=2,03) e 15 indivíduos adultos (média idade =27,63; DP=4,16). Foi utilizado o software Metropsis para avaliação da sensibilidade ao contraste de luminância de grade senoidal nas frequências espaciais de 0,2 cpg; 0,5 cpg; 1,0 cpg; 2,0 cpg; 4,2 cpg e 8,9 cpg e luminância média de 34,4 cd/m². Houve redução em toda a curva de sensibilidade ao contraste (SC) do grupo CC quando comparado ao grupo controle e não houve relação entre o tempo de privação e a redução da SC / The opacification of the lens present at birth is called Congenital Cataract (CC). The first weeks of life are important in visual development since there is not any significant difference in visual performance of children who had surgery within six weeks of life (with better visual performance) compared with children who underwent surgery after this period. Children who have visual deprivation during infancy due to bilateral cataracts have reduced spatial vision. The aim of this study was to assess the impact on Contrast Sensitivity Function (CSF) in children with Congenital Cataract surgery during the visual development age range. We evaluated three groups: 11 control children (mean age = 6.83, SD = 1.38), 9 children in the CC group (mean age = 6.87, SD = 2.03) and 15 adults (mean age = 27.63, SD = 4.16). Metropsis software was used to evaluate sensitivity to luminance contrast of the sinusoidal grating spatial frequencies of 0.2 cpd, 0.5 cpd, 1.0 cpd, 2.0 cpd, 4.2 cpd and 8.9 cpd with an average luminance of 34.4 cd / m². There was a reduction in the contrast sensitivity function (CSF) of the CC group compared to the control group and there was no correlation between the duration of deprivation and the impairment in the SC

Specifically oriented towards Russian culture, this study addresses the need in diplomacy for deeper cultural understanding. As research suggests a link between the inclusion of religious perspectives in second language acquisition (SLA) and student motivation and cultural empathy, this study examines how Russian language classrooms could leverage an understanding of Russian religious themes to foster cultural sensitivity. The study invited 24 second-year university students of Russian to complete a previously-validated assessment of cultural sensitivity: the Global Perspectives Inventory (GPI). Divided into a control and a treatment group, the participants also watched a short video depicting a story from Russian history on the interactive video platform, Ayamel. The control group viewed a set of 10 extra-textual annotations containing Russian cultural material highlighting secular themes from Russian culture, while the treatment group reviewed 10 that were more spiritually-themed. After viewing the respective annotations, participants completed a short, open-ended, Video Response Questionnaire (VRQ), and completed a GPI post-test. The findings from the VRQ suggested that the video intervention tended to challenge participants' previous perceptions of Russia, noted a general increase in positive, self-reported perspectives of Russian culture, and revealed a tendency in the treatment group to more often portray Russia as a multi-faceted, rather than monolithic, cultural entity. The comparison of the GPI pre-test and post-test scores revealed an inverse interaction between the collective scores of the control and treatment groups on two questions gauging affective responses to culture. For each of these questions on the post-test, the treatment group's collective score slightly increased and the control group's collective score slightly fell.The findings suggest that interaction with religious themes in SLA may promote feelings of commonality and empathy with a foreign culture. As the relative, religious homogeneity of the sample constitutes a threat to the external validity of this study, the researchers invite similar tests to be conducted in SLA among different population types.

This thesis discusses limit cycles and behavior of rumor models. The first part presents the deterministic Daley-Kendall model (DK) with arrivals and departures and comparison of the Susceptibles, Infectives and Removed (SIR) model and the DK model. The second result is a part of the qualitative analysis and the general behavior of extension of the Daley-Kendall model. Here we discuss how the halting rate of spreaders causes the model to change from a stable equilibrium or a stable limit cycle. In the third part we carry out model validation and use both synthetic data and real data sets and fit them to the numerical solutions of the extended Daley-Kendall model. Finally, we find the parameter estimates and standard errors. In this way we shall be able to decide whether the numerical solutions quantifying the relationships between the variables obtained from the qualitative analysis can be accepted as the best description of the data. We discuss sensitivity analysis results and traditional sensitivity functions.

abstract: The ability to self-regulate is arguably the single most important skill a child develops early in life. Self-regulation skills are consistently linked to indices of health, success, and wellbeing. The predominating perspective in self-regulation developmental research has emphasized the role of the early caregiving environment, specifically maternal characteristics and behavior, in shaping infants’ emerging regulatory skills. Using two complementary studies, this dissertation draws from a longitudinal sample of 322 low-income, Mexican American mother-infant dyads to better understand mothers’ and infants’ unique roles in contributing to emerging infant regulatory processes. The first study explores the unique contributions of intrinsic (i.e., infant gaze) and extrinsic (i.e., maternal gaze) factors in understanding infant dysregulated emotion and behavior during mother-infant interactions. Using actor partner interdependent models (APIMs), the role of infant and maternal gaze in understanding infant dysregulation were examined longitudinally across three mother-infant interaction tasks (i.e., soothing, teaching, and peekaboo), as well as within task. The expected relations among gaze and dysregulation did not emerge in the longitudinal model; however, differential patterns of associations emerged by task. Findings are discussed within the intersection of risk, culture, and the dyadic interaction context. The second study connects patterns of specific maternal behaviors (i.e., acknowledging, gaze, vocal appropriateness, appropriate range of affect, consistency of style, resourcefulness, and touch) associated with maternal sensitivity to infant cortisol reactivity and recovery. Latent profile analysis (LPA) revealed four distinct combinations of maternal sensitivity behaviors. One pattern emerged as a risk profile—differentiated by higher maternal stress—and was associated with significantly more infant cortisol recovery compared to other profiles. Both studies offer a more nuanced understanding of the respective roles of infant and maternal factors in the development of self-regulation. Further explication of developmental processes involved in early regulatory functioning has implications for advancing both scientific knowledge and improved targeting of prevention and early intervention efforts to promote optimal child outcomes, particularly in populations that at increased risk for developmental psychopathology. / Dissertation/Thesis / Doctoral Dissertation Family and Human Development 2019

Prior research has found a connection between dispositional factors such as rejection sensitivity and introversion and online dating behaviors including likelihood of use (Blackhart et al., 2014) and experience of use (Finkel et al., 2012; Whitty, 2008). The present study expands upon prior research to examine the relationship between these dispositional factors, and the impact of the possibility of explicit rejection on self-disclosure in participant-created dating app profiles. Adults between the ages of 18 and 60 will be introduced to an online dating app manipulated to contain either high or low potential for obvious rejection. Participants will then be asked to create a personal online profile. Participant perceptions of their own self-disclosure in the self-created profile as well as their disposition (introversion and rejection sensitivity) will be measured. It is hypothesized that rejection sensitive individuals as well as those rating lower in extraversion will report higher levels of self-disclosure in a non-explicit rejection dating app setting in comparison to an explicit rejection setting. The present research has implications for the field’s understanding of the experience of online dating app use for individuals as related to varying dispositional factors.

Previous studies evaluating the impact of trauma history and PTSD on pain sensitivity yield inconsistent findings; the presence of trauma-related negative affective states may account for these discrepancies. Therefore, the proposed study aimed to evaluate the effect of trauma-related negative affect and PTSD symptoms on sensory and affective components of pain sensitivity among trauma-exposed women. Adult women (N = 87) with low and high PTSD symptoms underwent an emotional disclosure paradigm, during which they wrote about a traumatic event or a neutral topic. Participants then completed a pain induction procedure. Compared to women with low PTSD symptoms, women with high PTSD symptoms demonstrated increased time to pain detection (e.g., threshold) and ability to withstand pain (e.g., tolerance), as well as increased pain intensity and when accounting for relevant covariates. Women with high PTSD symptoms who wrote about their worst traumatic experience reported higher pain unpleasantness relative to women with high PTSD symptoms who wrote about the neutral topic and women with low PTSD symptoms who wrote about either topic. Results suggest that PTSD symptoms and trauma-related negative affect may facilitate alterations in pain sensitivity in trauma-exposed women, but this relationship is complex and requires further exploration.

Anxiety sensitivity (AS) is associated with health behaviors such as low rates of physical activity, overeating, alcohol use, and poor sleep; however, interventions targeting AS via exercise-based interoceptive exposure have not assessed these as outcomes. In addition, previous studies are limited by brief follow-up periods. This study aimed to replicate previous aerobic exercise interoceptive exposures with an extended (6-week) follow-up and measurement of health behaviors. Participants were 44 sedentary young adults with elevated AS randomized to intervention (6 20-minute sessions of moderate-intensity treadmill walking) or assessment-only control. Assessments took place at baseline, week 2 (post-treatment), week 4, and week 8 with measurements of AS (ASI-3), physical activity (7-Day PAR), sleep (ISI), binge eating, alcohol use, depression (PHQ-8), anxiety (GAD-7), and stress (PSS-4). The intervention condition demonstrated a marginally significant reduction in AS compared to control at week 4 which eroded by week 8. There were no significant between-group differences for health behavior change. The intervention condition demonstrated decreases in depression, general anxiety, and perceived stress compared to control, but these effects eroded by week 4. There was no difference in findings for participants with BMI<25 vs. those with BMI>=25. Findings indicate that a brief intervention might not be sufficient to produce lasting changes in AS without additional treatment. Intervention effects were not as strong in this study compared to previous reports, which may be due to the size and greater racial/ethnic diversity of the current sample. Future research should objectively measure physical activity and explore individual variability in treatment response.