Object tracking using a camera gimbal mechanism

TCC(graduação) - Universidade Federal de Santa Catarina. Centro Tecnológico. Engenharia de Controle e Automação.Este trabalho apresenta um sistema de detecção e rastreamento de objetos no campo de visão da câmera acoplado a um mecanismo robótica com três graus de liberdade denominada Gimbal. O processo de detecção de objetos em tempo real usa uma ferramenta de visão computacional chamada YOLO e se comunica entre periféricos com um sistema operacional robótico (ROS) em uma aeronave pilotada remotamente (RPA) usando um computador de bordo para processar os dados. O sistema de controle é projetado usando os conceitos matemáticos de cinemática direta e inversa do Gimbal para estimar a posição do ângulo e manter o objeto centralizado na resolução da imagem. Para comparar a matemática de controle cinemático inverso, dois controladores lineares Proporcional-Integral foram ajustados para agir com base no sinal de erro da posição do pixel para cada eixo. Para o estudo, foi utilizado um ambiente de simulação robótica no software Gazebo para testar e ajustar os controladores realizando alguns experimentos antes de utilizá-lo na vida real, reduzindo a probabilidade de falha ou danos ao hardware. O hardware utilizado para o teste é um conjunto de componentes fornecidos por uma única empresa, facilitando a conexão entre aeronave, câmera, Gimbal e computador de bordo. Os resultados das simulações e experimentos práticos validam a teoria e permitem que a estrutura rastreie o objeto mantendo-o no campo de visão da câmera enquanto o RPA se move para inspecionar todo o equipamento.This work presents a system development for detecting and tracking objects on the camera's field of view coupled to a mechanism of three degrees of freedom called Gimbal. The computer vision technique, You Only Look Once (YOLO), detects an object on image in execution time and communicates between peripherals at Robotic Operating System (ROS) on a remotely piloted aircraft (RPA) processing the data and controling the Gimbal's joint using an on-board computer. The control system is designed using Gimbal's forward and inverse kinematics mathematical concepts to estimate the angle position maintaining the object centered on image resolution. In order to compare control techniques, a Proportional-Integral linear controllers have been designed to act based on error signal from pixel position to each axis independently. To refine the algorithm it was used a robotic simulation environment from Gazebo software to test and tune controllers and perform some experiments before starting the practical tests, reducing the probability of failure or damaging the hardware. The hardware used was a set of components provided from only one company, facilitating the connection between aircraft, camera, Gimbal and on-board computer. The results of simulation and practical experiments validate the theory and allows the mechanism to track the object maintaining it on camera's field of view while the RPA is in motion to inspect the interest area

Considering Stress in a Nursing Student Context: Pre-Admission to Pre-Graduation

In moderation, stress is a normal response to a perceived challenge which can motivate an individual to perform at their best. Nursing students consistently report a significant amount of stress which has been found to be greater than their non-nursing peers. The purpose of this study is to assess the level of stress reported by second-semester freshman and sophomore students who have declared nursing as a major, compared with the level of stress experienced by junior and senior students who are enrolled in the university\u27s nursing program. Through this comparison, a conclusion can be drawn as to the level of stress experienced while enrolled in a nursing program, with the level of stress prior to being exposed to the challenges presented by the program. It is intended that the outcomes from this study can be utilized to address stress as it relates to a nursing student from pre-admission through graduation

Traumatic Penumbra: Opportunities for Neuroprotective and Neurorestorative Processes

Traumatic brain injury (TBI) is a major cause of morbidity and mortality worldwide. Understanding the pathophysiology of TBI is crucial for the development of more effective therapeutic strategies. At the moment of the traumatic impact, transfer of kinetic forces causes neurologic damage; this primary injury triggers a secondary wave of biochemical cascades, together with metabolic and cellular changes, called secondary neural injury. These areas of ongoing secondary injury, or areas of “traumatic penumbra,” represent crucial targets for therapeutic interventions. This chapter is focused on the interplay between progression of parenchymal injury and the neuroprotective and neurorestorative processes that are emerging and developing subsequently to traumatic impact. Thus, we emphasized the role of traumatic penumbra in TBI pathogenesis and suggested a crucial contribution of the neurovascular units (NVUs) and paracrine effects of exosomes and miRNAs in promoting neurological recovery

Effect of Caffeine and Other Methylxanthines on Aβ-Homeostasis in SH-SY5Y Cells

Methylxanthines (MTX) are alkaloids derived from the purine-base xanthine. Whereas especially caffeine, the most prominent known MTX, has been formerly assessed to be detrimental, this point of view has changed substantially. MTXs are discussed to have beneficial properties in neurodegenerative diseases, however, the mechanisms of action are not completely understood. Here we investigate the effect of the naturally occurring caffeine, theobromine and theophylline and the synthetic propentofylline and pentoxifylline on processes involved in Alzheimer’s disease (AD). All MTXs decreased amyloid-β (Aβ) level by shifting the amyloid precursor protein (APP) processing from the Aβ-producing amyloidogenic to the non-amyloidogenic pathway. The α-secretase activity was elevated whereas β-secretase activity was decreased. Breaking down the molecular mechanism, caffeine increased protein stability of the major α-secretase ADAM10, downregulated BACE1 expression and directly decreased β-secretase activity. Additionally, APP expression was reduced. In line with literature, MTXs reduced oxidative stress, decreased cholesterol and a decreased in Aβ1-42 aggregation. In conclusion, all MTXs act via the pleiotropic mechanism resulting in decreased Aβ and show beneficial properties with respect to AD in neuroblastoma cells. However, the observed effect strength was moderate, suggesting that MTXs should be integrated in a healthy diet rather than be used exclusively to treat or prevent AD

Pain catastrophizing is associated with the Val66Met polymorphism of the brainderived neurotrophic factor in fibromyalgia

Background: Fibromyalgia (FM) is a musculoskeletal chronic pain syndrome that impacts negatively patient’s daily lives. Its pathogenesis is characterized by a complex relationship between biological and psychosocial factors not fully understood yet. Pain catastrophizing is associated with FM and is an important predictor of outcomes. This study aimed to answer two questions: (i) whether the allele and genotype frequencies of BDNF Val66Met (rs6265) polymorphism differs between FM patients and healthy controls (HC); and (ii) if the BDNF Val66Met polymorphism is a factor that predicts pain catastrophizing in FM. Methods: In a cross-sectional design, 108 FM patients and 108 HC were included. FM patients responded to the Brazilian Portuguese version of the Pain Catastrophizing Scale (BP-PCS) to assess pain catastrophizing, as well as other validated tools for anxiety (The State-Trait Anxiety Inventory - STAI), depression (Beck Depression Inventory II – BDI-II) and functional aspects (Fibromyalgia Impact Questionnaire - FIQ; Central Sensitization Inventory validated and adapted for Brazilian population - CSI-BP; Pittsburgh Sleep Quality Index - PSQI; and Resilience Scale). All subjects were genotyped for the BDNF Val66Met polymorphism. Results: Val allele was significantly more frequent in FM patients compared to the control group (p < 0.05). Also, FM patients with Val/Val genotype showed more pain catastrophizing thoughts, and this genotype was significantly associated with magnification and rumination dimensions of BP-PCS (p < 0.05). Furthermore, there were significant differences in levels of anxiety and symptoms of depression, years of education, and the functional situation between the FM and control groups. Conclusions: The findings show an association of BDNF Val66Met polymorphism with pain catastrophizing in FM, which opens new avenues to comprehend the interplay between molecular genetic characteristics and neuroplasticity mechanisms underpinning FM

Cytotoxic effect and oxidative damage of organic extract from Artemisia verlotorum in human cancer cell lines

Neste estudo, avaliamos os efeitos citotóxico e oxidativo dos extratos orgânico e aquoso de folhas da Artemisia verlotorum em linhagens celulares derivadas de câncer humano. Apenas o extrato orgânico demonstrou atividade citotóxica na linhagem celular de adenocarcinoma de cólon HT-29 na concentração de 100 µg/mL. O extrato orgânico foi, então, analisado em três linhagens celulares: adenocarcinoma de cólon, HT-29; carcinoma de pulmão de não-pequenas células, NCI-H460 e câncer renal, RXF-393, demonstrando valores de IC50 que variaram de 21 a 38 µg/mL. A linhagem celular RXF-393 apresentou maior sensibilidade ao extrato e foi usada nas análises seguintes. Nesta linhagem, o extrato orgânico induziu um significativo aumento dose-dependente na peroxidação lipídica. A maior concentração (IC80) do extrato reduziu em 50 % a atividade da isoforma mitocondrial da enzima superóxido dismutase (SOD2). Estes achados sugerem que o extrato orgânico de folhas da Artemisia verlotorum induz morte celular através de um aumento no dano oxidativo em linhagens celulares de câncer humano.In this study the cytotoxic and oxidative effects of organic and aqueous extracts from the leaves of Artemisia verlotorum in human cancer cell lines was evaluated. Only the organic extract demonstrated cytotoxic activity in HT-29 colon adenocarcinoma cell line at 100 µg/mL. The organic extract was then analyzed in three cell lines: HT-29 colon adenocarcinoma; NCI-H460 non-small-cell lung cancer cell line and RXF-393 renal cancer cell line, demonstrating values of IC50 ranging from 21 to 38 µg/mL. The RXF-393 cell line displayed higher sensibility to these extract and it was used in the following analyses. In these cells, the organic extract induced a significant dose-dependent increase in the lipid peroxidation. The highest concentration (IC80) of the extract reduced in 50 % the activity of the mitochondrial isoform of the enzyme superoxide dismutase (SOD2). These findings suggest that the organic extract from the leaves of Artemisia verlotorum induces cell death through an increase in the oxidative damage in human cancer cell linesColegio de Farmacéuticos de la Provincia de Buenos Aire

Vitamin D and Its Analogues Decrease Amyloid-β (Aβ) Formation and Increase Aβ-Degradation

Alzheimer’s disease (AD) is characterized by extracellular plaques in the brain, mainly consisting of amyloid-β (Aβ), as derived from sequential cleavage of the amyloid precursor protein. Epidemiological studies suggest a tight link between hypovitaminosis of the secosteroid vitamin D and AD. Besides decreased vitamin D level in AD patients, an effect of vitamin D on Aβ-homeostasis is discussed. However, the exact underlying mechanisms remain to be elucidated and nothing is known about the potential effect of vitamin D analogues. Here we systematically investigate the effect of vitamin D and therapeutically used analogues (maxacalcitol, calcipotriol, alfacalcidol, paricalcitol, doxercalciferol) on AD-relevant mechanisms. D2 and D3 analogues decreased Aβ-production and increased Aβ-degradation in neuroblastoma cells or vitamin D deficient mouse brains. Effects were mediated by affecting the Aβ-producing enzymes BACE1 and γ-secretase. A reduced secretase activity was accompanied by a decreased BACE1 protein level and nicastrin expression, an essential component of the γ-secretase. Vitamin D and analogues decreased β-secretase activity, not only in mouse brains with mild vitamin D hypovitaminosis, but also in non-deficient mouse brains. Our results further strengthen the link between AD and vitamin D, suggesting that supplementation of vitamin D or vitamin D analogues might have beneficial effects in AD prevention

Comparación de caracteres corporales y del veneno de <i>Bothrops alternatus</i> entre poblaciones de las provincias de Buenos Aires y Entre Ríos, Argentina

Comparamos caracteres corporales y producción de veneno de ejemplares de Bothrops alternatus de una población aislada geográficamente (Olavarría, región de Tandilia, Buenos Aires) con otra en su área de distribución continua de Concordia (Entre Ríos). Estudiamos el largo corporal, peso, separación entre dientes inoculadores, cantidad de veneno y de proteínas en el veneno por ejemplar. No se hallaron diferencias en los caracteres estudiados entre ambas poblaciones (p > 0.05). Las hembras fueron mayores que los machos en ambas muestras,entre un 12-18% (p 0.5; Olavarría: 142 ± 65 mg/animal,Concordia: 160 ± 80 mg/animal), aún ajustando la cantidad de veneno producida respecto al tamaño, mediante el cociente veneno/largo corporal (p >0.6). Tampoco hubo diferencias en el contenido proteico, siendo para ambas muestras de 0.697 ± 0.096 mg de proteínas/mg de veneno seco. Nuestros datos sugieren que los ejemplares de la población aislada de Tandiliano presentan variaciones en el tamaño corporal o en la cantidad de veneno producida, respecto a los ejemplares de Concordia.Asociación Herpetológica Argentina (AHA