375 research outputs found

    An ant colony system approach for variants of traveling salesman problem with time windows

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    The Traveling Salesman Problem with Time Windows has important applications in routing and scheduling and has been extensively studied in literature. In the paper, a mathematical formulation of the temporal-Traveling Salesman Problem with Time Windows is presented and a metaheuristic based on Ant Colony System is proposed and implemented. Computational experience on a benchmark problem is reported and a case study is analyzed, where interesting results are obtained

    Avaliação de indicadores associados à conservação dos recursos hídricos em distintos sistemas de uso da terra para valoração de serviços ambientais.

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    O objetivo do trabalho é avaliar e comparar indicadores ambientais associados aos recursos hídricos entre distintos sistemas de uso da terra, desde campo e oresta natural passando por sistemas agrosilvopastoril (uma modalidade de sistema agro orestal) e silvicultural até o outro extremo, em monocultura de plantas anuais. A quanti cação e a modelagem desta relação subsidiarão os estudos de valoração dos serviços ambientais prestados nos diferentes usos da terra. ABSTRACT - There is an association between the type and intensity of land use and the quantity and quality of environmental services generated but there are knowledge gaps of the quanti cation of environmental indicators. The objective is to evaluate and compare environmental indicators associated to water resources between different land uses systems from natural eld and forest, silvopastoral and silviculture system to annual crops. The study plots are located in Ponta Grossa, Tibagi River basin, Atlantic Forest biome, Brazil. The quanti cation and modeling these studies will support the valuation of environmental services and hydrological processes in different land uses

    Graphene-Paper-Based Electrodes on Plastic and Textile Supports as New Platforms for Amperometric Biosensing

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    The possibility of exfoliating graphite into graphene sheets allows the researchers to produce a material, termed “graphene paper” (G-paper), conductive as graphite but more flexible and processable. G-paper is already used for electronic applications, like conductors, antennas, and heaters, outperforming metal conductors thanks to its high flexibility, lightness, chemical stability, and compatibility with polymeric substrates. Here, the effectiveness in the use of G-paper for the realization of electrodes on flexible plastic substrates and textiles, and their applicability as amperometric sensors are demonstrated. The performance of these devices is compared with commercial platforms made of carbon-based inks, finding that they outperform commercial devices in sensing nicotinamide adenine dinucleotide (NADH), a key molecule for enzymatic biosensing; the electrodes can achieve state-of-the-art sensitivity (107.2 μA mm−1 cm−2) and limit of detection (0.6 × 10−6 m) with no need of additional functionalization. Thanks to this property, the stable deposition of a suitable enzyme, namely lactate dehydrogenase, on the electrode surface is used as a proof of concept of the applicability of this new platform for the realization of a biosensor. The possibility of having a single material suitable for antennas, electronics, and now sensing opens new opportunities for smart fabrics in wearable electronic applications

    Graphene-Paper-Based Electrodes on Plastic and Textile Supports as New Platforms for Amperometric Biosensing

    Get PDF
    The possibility of exfoliating graphite into graphene sheets allows the researchers to produce a material, termed “graphene paper” (G-paper), conductive as graphite but more flexible and processable. G-paper is already used for electronic applications, like conductors, antennas, and heaters, outperforming metal conductors thanks to its high flexibility, lightness, chemical stability, and compatibility with polymeric substrates. Here, the effectiveness in the use of G-paper for the realization of electrodes on flexible plastic substrates and textiles, and their applicability as amperometric sensors are demonstrated. The performance of these devices is compared with commercial platforms made of carbon-based inks, finding that they outperform commercial devices in sensing nicotinamide adenine dinucleotide (NADH), a key molecule for enzymatic biosensing; the electrodes can achieve state-of-the-art sensitivity (107.2 μA mm−1 cm−2) and limit of detection (0.6 7 10−6 m) with no need of additional functionalization. Thanks to this property, the stable deposition of a suitable enzyme, namely lactate dehydrogenase, on the electrode surface is used as a proof of concept of the applicability of this new platform for the realization of a biosensor. The possibility of having a single material suitable for antennas, electronics, and now sensing opens new opportunities for smart fabrics in wearable electronic applications

    Olfactory neuroepithelium alterations and cognitive correlates in schizophrenia

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    BACKGROUND: Few studies have investigated alterations of olfactory neuroepithelium (ONE) as a biomarker of schizophrenia, and none its association with cognitive functioning. METHOD: Fresh ONE cells from twelve patients with schizophrenia and thirteen healthy controls were collected by nasal brushing, cultured in proper media and passed twelve times. Markers of cell proliferation (BrdU incorporation, Cyclin-D1 and p21 protein level) were quantified.Cognitive function was measured using Brief Neuropsychological Examination-2. PRIMARY OUTCOME: proliferation of ONE cells from schizophrenic patients at passage 3. Secondary outcome: association between alteration of cell proliferation and cognitive function. RESULTS: Fresh ONE cells from patients showed a faster cell proliferation than those from healthy controls at passage 3. An opposite trend was observed at passage 9, ONE cells of patients with schizophrenia showing slower cell proliferation as compared to healthy controls. In schizophrenia, overall cognitive function (Spearman's rho -0.657, p\u202f<\u202f0.01), verbal memory - immediate recall, with interference at 10\u202fs and 30\u202fs (Spearman's rho from -0.676 to 0.697, all p\u202f<\u202f0.01) were inversely associated with cell proliferation at passage 3. CONCLUSION: Fresh ONE cells collected by nasal brushing might eventually represent a tool for diagnosing schizophrenia based upon markers of cell proliferation, which can be easily implemented as single-layer culture. Cell proliferation at passage 3 can be regarded as a promising proxy of cognitive functioning in schizophrenia. Future studies should replicate these findings, and may assess whether ONE alterations are there before onset of psychosis, serving as an early sign in patients with at risk mental state

    ESTUDO DA PAISAGEM DO COREDE NORTE BASEADO EM SISTEMA SIG: INTELIGÊNCIA TECNOLÓGICA ESSENCIAL NA CONSTRUÇÃO DE CIDADES SUSTENTÁVEIS

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    O presente artigo tem por objetivo apresentar um processo de leitura da paisagem regional, a partir do método de Unidades de Paisagem (UPs) com o auxílio de Sistema de Informações Geográficas (SIG). Aplicou-se aos municípios pertencentes ao Perfil Socioeconômico COREDE Norte, do estado do Rio Grande do Sul. Esse estudo foi desenvolvido na disciplina de Projeto Urbano e Paisagem, da Universidade Federal da Fronteira Sul - UFFS, fundamentado em discussões teórico-metodológicas, levantamento fotográfico, elaboração de cartografia fundamentados nos elementos e na estrutura da paisagem, cujos fatores antrópicos e ecológicos compõem os mosaicos paisagísticos da região. O SIG aplicado ao planejamento da paisagem, apresentou-se como importante mecanismo para o conhecimento e sistematização da realidade territorial, resultando na identificação e caracterização de UPS, que são porções territoriais estratégicas para o desenvolvimento e a gestão espacial. Nesta perspectiva, o SIG ainda apresenta-se como uma ferramenta eficiente para o monitoramento, e gestão dos espaços urbanos, o que pode contribuir significativamente para a construção de cidades inteligentes e sustentáveis

    AMS INSIGHT—Absorbable Metal Stent Implantation for Treatment of Below-the-Knee Critical Limb Ischemia: 6-Month Analysis

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    Endoluminal treatment of infrapopliteal artery lesions is a matter of controversy. Bioabsorbable stents are discussed as a means to combine mechanical prevention of vessel recoil with the advantages of long-term perspectives. The possibility of not having a permanent metallic implant could permit the occurrence of positive remodeling with lumen enlargement to compensate for the development of new lesions. The present study was designed to investigate the safety of absorbable metal stents (AMSs) in the infrapopliteal arteries based on 1- and 6-month clinical follow-up and efficacy based on 6-month angiographic patency. One hundred seventeen patients with 149 lesions with chronic limb ischemia (CLI) were randomized to implantation of an AMS (60 patients, 74 lesions) or stand-alone percutaneous transluminal angioplasty (PTA; 57 patients, 75 lesions). Seven PTA-group patients “crossed over” to AMS stenting. The study population consisted of patients with symptomatic CLI (Rutherford categories 4 and 5) and de novo stenotic (>50%) or occlusive atherosclerotic disease of the infrapopliteal arteries who presented with a reference diameter of between 3.0 and 3.5 mm and a lesion length of <15 mm. The primary safety endpoint was defined as absence of major amputation and/or death within 30 days after index intervention and the primary efficacy endpoint was the 6-month angiographic patency rate as confirmed by core-lab quantitative vessel analysis. The 30-day complication rate was 5.3% (3/57) and 5.0% (3/60) in patients randomized for PTA alone and PTA followed by AMS implantation, respectively. On an intention-to-treat basis, the 6-month angiographic patency rate for lesions treated with AMS (31.8%) was significantly lower (p = 0.013) than the rate for those treated with PTA (58.0%). Although the present study indicates that the AMS technology can be safely applied, it did not demonstrate efficacy in long-term patency over standard PTA in the infrapopliteal vessels
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