934 resultados para Interaction human robot
Resumo:
Includes bibliography
Resumo:
Includes bibliography
Resumo:
Severely disabled children have little chance of environmental and social exploration and discovery. This lack of interaction and independency may lead to an idea that they are unable to do anything by themselves. In an attempt to help children in this situation, educational robotics can offer and aid, once it can provide them a certain degree of independency in the exploration of environment. The system developed in this work allows the child to transmit the commands to a robot through myoelectric and movement sensors. The sensors are placed on the child's body so they can obtain information from the body inclination and muscle contraction, thus allowing commanding, through a wireless communication, the mobile entertainment robot to carry out tasks such as play with objects and draw. In this paper, the details of the robot design and control architecture are presented and discussed. With this system, disabled children get a better cognitive development and social interaction, balancing in a certain way, the negative effects of their disabilities. © 2012 IEEE.
Resumo:
The use of mobile robots turns out to be interesting in activities where the action of human specialist is difficult or dangerous. Mobile robots are often used for the exploration in areas of difficult access, such as rescue operations and space missions, to avoid human experts exposition to risky situations. Mobile robots are also used in agriculture for planting tasks as well as for keeping the application of pesticides within minimal amounts to mitigate environmental pollution. In this paper we present the development of a system to control the navigation of an autonomous mobile robot through tracks in plantations. Track images are used to control robot direction by preprocessing them to extract image features. Such features are then submitted to a support vector machine in order to find out the most appropriate route. The overall goal of the project to which this work is connected is to develop a real time robot control system to be embedded into a hardware platform. In this paper we report the software implementation of a support vector machine, which so far presented around 93% accuracy in predicting the appropriate route. © 2012 IEEE.
Resumo:
High-grade prostate cancers express high levels of matrix metalloproteinases (MMPs), major enzymes involved in tumor invasion and metastasis. However, the tumor cell lines commonly employed for prostate cancer research express only small amounts of MMPs when cultivated as monolayer cultures, in common culture media. The present study was conducted to ascertain whether culture conditions that include fibronectin can alter MMP2 and MMP9 expression by the human prostatic epithelial cell lines RWPE-1, LNCaP and PC-3. These cells were individually seeded at 2×104cells/cm2, cultivated until they reached 80% confluence, and then exposed for 4h to fibronectin, after which the conditioned medium was analyzed by gelatin zymography. Untreated cells were given common medium. Only RWPE-1 cells express detectable amounts of MMP9 when cultivated in common medium, whereas the addition of fibronectin induced high expression levels of pro and active forms of MMP2 in all tested cell lines. Our findings demonstrate that normal and tumor prostate cell lines express MMP2 activity when in contact with extracellular matrix components or blood plasma proteins such as fibronectin. Future studies of transcriptomes and proteomes in prostate cancer research using these cell lines should not neglect these important conclusions. © 2012 Elsevier Inc..
Resumo:
Background:Hepatitis C is a disease spread throughout the world. Hepatitis C virus (HCV), the etiological agent of this disease, is a single-stranded positive RNA virus. Its genome encodes a single precursor protein that yields ten proteins after processing. NS5A, one of the non-structural viral proteins, is most associated with interferon-based therapy response, the approved treatment for hepatitis C in Brazil. HCV has a high mutation rate and therefore high variability, which may be important for evading the immune system and response to therapy. The aim of this study was to analyze the evolution of NS5A quasispecies before, during, and after treatment in patients infected with HCV genotype 3a who presented different therapy responses.Methods:Viral RNA was extracted, cDNA was synthesized, the NS5A region was amplified and cloned, and 15 clones from each time-point were sequenced. The sequences were analyzed for evolutionary history, genetic diversity and selection.Results:This analysis shows that the viral population that persists after treatment for most non-responder patients is present in before-treatment samples, suggesting it is adapted to evade treatment. In contrast, the population found in before treatment samples from most end-of-treatment responder patients either are selected out or appears in low frequency after relapse, therefore changing the population structure. The exceptions illustrate the uniqueness of the evolutionary process, and therefore the treatment resistance process, in each patient.Conclusion:Although evolutionary behavior throughout treatment showed that each patient presented different population dynamics unrelated to therapy outcome, it seems that the viral population from non-responders that resists the treatment already had strains that could evade therapy before it started. © 2013 Bittar et al.
Resumo:
This paper presents a usability evaluation of the MTE (Ministry of Labor e Employment) website in order to measure the effectiveness, efficiency and user satisfaction regarding the website. The participants were 12 users (07 users were female and 05 male). The results indicate that although the education level of all participants and computing experience, many of them have had difficulty in finding information and do not recommend the site. © 2013 Springer-Verlag Berlin Heidelberg.
Resumo:
Feline immunodeficiency virus (FIV) infection has been the focus of several studies because this virus exhibits genetic and pathogenic characteristics that are similar to those of the human immunodeficiency virus (HIV). FIV causes acquired immunodeficiency syndrome (AIDS) in cats, nevertheless, a large fraction of infected cats remain asymptomatic throughout life despite of persistent chronic infection. This slow disease progression may be due to the presence of factors that are involved in the natural resistance to infection and the immune response that is mounted by the animals, as well as due to the adaptation of the virus to the host. Therefore, the study of virus-host interaction is essential to the understanding of the different patterns of disease course and the virus persistence in the host, and to help with the development of effective vaccines and perhaps the cure of FIV and HIV infections. © 2013 Elsevier Ltd. All rights reserved.
Resumo:
The Pterogyne nitens (Fabaceae) tree, native to South America, has been found to produce guanidine alkaloids as well as bioactive flavonols such as kaempferol, quercetin, and rutin. In the present study, we examined the possibility of interaction between human ATP-binding cassette (ABC) transporter ABCB1 and four guanidine alkaloids isolated from P. nitens (i.e., galegine, nitensidine A, pterogynidine, and pterogynine) using human T cell lymphoblast-like leukemia cell line CCRF-CEM and its multi-drug resistant (MDR) counterpart CEM/ADR5000. In XTT assays, CEM/ADR5000 cells were resistant to the four guanidine alkaloids compared to CCRF-CEM cells, although the four guanidine alkaloids exhibited some level of cytotoxicity against both CCRF-CEM and CEM/ADR5000 cells. In ATPase assays, three of the four guanidine alkaloids were found to stimulate the ATPase activity of ABCB1. Notably, nitensidine A was clearly found to stimulate the ATPase activity of ABCB1 as strongly as the control drug, verapamil. Furthermore, the cytotoxic effect of nitensidine A on CEM/ADR5000 cells was synergistically enhanced by verapamil. Nitensidine A inhibited the extrusion of calcein by ABCB1. In the present study, the possibility of interaction between ABCB1 and two synthetic nitensidine A analogs (nitensidine AT and AU) were examined to gain insight into the mechanism by which nitensidine A stimulates the ATPase activity of ABCB1. The ABCB1-dependent ATPase activity stimulated by nitensidine A was greatly reduced by substituting sulfur (S) or oxygen (O) for the imino nitrogen atom (N) in nitensidine A. Molecular docking studies on human ABCB1 showed that, guanidine alkaloids from P. nitens dock to the same binding pocket as verapamil. Nitensidine A and its analogs exhibit similar binding energies to verapamil. Taken together, this research clearly indicates that nitensidine A is a novel substrate for ABCB1. The present results also suggest that the number, binding site, and polymerization degree of the isoprenyl moiety in the guanidine alkaloids and the imino nitrogen atom cooperatively contribute to their stimulation of ABCB1's ATPase activity. © 2013 Elsevier GmbH. All rights reserved.
Resumo:
Abstract If there is a geographical area that will be particularly affected by the tragedy of September 11, that will be the international borders of the United States. It is understandable that a country that enters in a state of war after been attacked with enormous losses, reacts by closing its international borders. Such immediate reaction has now been substituted by a more strict control over everything that crosses the border but, a fact remains, the border life is not going to be what it used to before September 11. In the short run, everything that crosses the border has slowed down by new controls. In the long run many things will return to what it was before that Tuesday, but for a long while, life at the border will not be the same. An intense interaction of more than twelve million people from the two sides of the U.S.-Mexico border have made us live in many instances as if the border does not exist. This is the case among many of us in the way we practice our family life. For the planning of weddings, birthdays, reunions, ceremonies, the border is more virtual than real. This is reversed as we get more serious in what it means to the space where institutions, the laws and the governments reminds us that there is a line that marks the beginning and the end of two different nations.
Resumo:
INTRODUCTION: Regenerative therapies using biomaterials require accurate information on interactions between the implanted material and the human body. To improve the process of bone regeneration it is necessary to obtain a better understanding of the influence of the surfaces on the early stages of osseointegration. This work aims to investigate the dynamic interaction between simulated body fluid (SBF) and titanium surfaces (Ti cp) immediately after their first contact. METHODS: Ti cp samples were passed through physicochemical treatments after immersion in acid solution, alkaline solution and solutions containing TiO2 and Ca2+, to obtain three different surfaces. These were characterized by electron microscopy and free energy estimates. The evaluation of the interaction with SBF was performed by measuring the dynamic contact angles after contacting the surfaces. RESULTS: The effects of SBF wettability were more significant on surfaces according to high energy estimates. A comparative analysis of the three types of surfaces showed that fluid spreading was greater in samples with greater polar components, indicating that the surface nature influences interactions in the early stages of osseointegration. CONCLUSION: The results indicate the influence of polar interactions in the dynamic wettability of the SBF. It is possible that these interactions can also influence cellular viability on surfaces. Based on these results, new experiments are being designed to improve the presented methodology as a tool for the evaluation of biomaterials without the need for in vivo experiments.
Resumo:
In different regions of Brazil, population growth and economic development can degrade water quality, compromising watershed health and human supply. Because of its ability to combine spatial and temporal data in the same environment and to create water resources management (WRM) models, the Geographical Information System (GIS) is a powerful tool for managing water resources, preventing floods and estimating water supply. This paper discusses the integration between GIS and hydrological models and presents a case study relating to the upper section of the Paraíba do Sul Basin (Sao Paulo State portion), situated in the Southeast of Brazil. The case study presented in this paper has a database suitable for the basin's dimensions, including digitized topographic maps at a 50,000 scale. From an ArcGIS®/ArcHydro Framework Data Model, a geometric network was created to produce different raster products. This first grid derived from the digital elevation model grid (DEM) is the flow direction map followed by flow accumulation, stream and catchment maps. The next steps in this research are to include the different multipurpose reservoirs situated along the Paraíba do Sul River and to incorporate rainfall time series data in ArcHydro to build a hydrologic data model within a GIS environment in order to produce a comprehensive spatial-temporal model.
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
The aim of the current study was to evaluate the presence of debris and smear layer after endodontic irrigation with different formulations of 2% chlorhexidine gluconate (CHX) and its effects on the push-out bond strength of an epoxy-based sealer on the radicular dentin. One hundred extracted human canines were prepared to F5 instrument and irrigated with 2.5% sodium hypochlorite and 17% ethylenediaminetetraacetic acid. Fifty teeth were divided into five groups (n=10), according to the final irrigation protocol with different 2% CHX formulations: G1 (control, no final rinse irrigation), G2 (CHX solution), G3 (CHX gel), G4 (Concepsis), and G5 (CHX Plus). In sequence, the specimens were submitted to scanning electron microscopy (SEM) analysis, in the cervical-medium and medium-apical segments, to evaluate the presence of debris and smear layer. The other 50 teeth were treated equally to a SEM study, but with the root canals filled with an epoxy-based endodontic sealer and submitted to a push-out bond strength test, in the cervical, middle, and apical thirds. G2, G3, G4, and G5 provided higher precipitation of the debris and smear layer than G1 (P<0.05), but these groups were similar to each other (P>0.05), in both segments. The values obtained in the push out test did not differ between groups, independent of the radicular third (P>0.05). The CHXs formulations caused precipitation of the debris and smear layer on the radicular dentin, but these residues did not interfere in the push-out bond strength of the epoxy-based sealer. Microsc. Res. Tech. 77:17-22, 2014. (c) 2013 Wiley Periodicals, Inc.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)