65 research outputs found

    Unsupervised Learning for Subterranean Junction Recognition Based on 2D Point Cloud

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    This article proposes a novel unsupervised learning framework for detecting the number of tunnel junctions in subterranean environments based on acquired 2D point clouds. The implementation of the framework provides valuable information for high level mission planners to navigate an aerial platform in unknown areas or robot homing missions. The framework utilizes spectral clustering, which is capable of uncovering hidden structures from connected data points lying on non-linear manifolds. The spectral clustering algorithm computes a spectral embedding of the original 2D point cloud by utilizing the eigen decomposition of a matrix that is derived from the pairwise similarities of these points. We validate the developed framework using multiple data-sets, collected from multiple realistic simulations, as well as from real flights in underground environments, demonstrating the performance and merits of the proposed methodology

    Unsupervised Learning for Subterranean Junction Recognition Based on 2D Point Cloud

    Get PDF
    This article proposes a novel unsupervised learning framework for detecting the number of tunnel junctions in subterranean environments based on acquired 2D point clouds. The implementation of the framework provides valuable information for high level mission planners to navigate an aerial platform in unknown areas or robot homing missions. The framework utilizes spectral clustering, which is capable of uncovering hidden structures from connected data points lying on non-linear manifolds. The spectral clustering algorithm computes a spectral embedding of the original 2D point cloud by utilizing the eigen decomposition of a matrix that is derived from the pairwise similarities of these points. We validate the developed framework using multiple data-sets, collected from multiple realistic simulations, as well as from real flights in underground environments, demonstrating the performance and merits of the proposed methodology

    The emergence and evolution of the research fronts in HIV/AIDS research

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    In this paper, we have identified and analyzed the emergence, structure and dynamics of the paradigmatic research fronts that established the fundamentals of the biomedical knowledge on HIV/AIDS. A search of papers with the identifiers "HIV/AIDS", "Human Immunodeficiency Virus", "HIV-1" and "Acquired Immunodeficiency Syndrome" in the Web of Science (Thomson Reuters), was carried out. A citation network of those papers was constructed. Then, a sub-network of the papers with the highest number of inter-citations (with a minimal in-degree of 28) was selected to perform a combination of network clustering and text mining to identify the paradigmatic research fronts and analyze their dynamics. Thirteen research fronts were identified in this sub-network. The biggest and oldest front is related to the clinical knowledge on the disease in the patient. Nine of the fronts are related to the study of specific molecular structures and mechanisms and two of these fronts are related to the development of drugs. The rest of the fronts are related to the study of the disease at the cellular level. Interestingly, the emergence of these fronts occurred in successive "waves" over the time which suggest a transition in the paradigmatic focus. The emergence and evolution of the biomedical fronts in HIV/AIDS research is explained not just by the partition of the problem in elements and interactions leading to increasingly specialized communities, but also by changes in the technological context of this health problem and the dramatic changes in the epidemiological reality of HIV/AIDS that occurred between 1993 and 1995

    Overactive bladder-18 years - Part II

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    Traditionally, the treatment of overactive bladder syndrome has been based on the use of oral medications with the purpose of reestablishing the detrusor stability. The recent better understanding of the urothelial physiology fostered conceptual changes, and the oral anticholinergics - pillars of the overactive bladder pharmacotherapy - started to be not only recognized for their properties of inhibiting the detrusor contractile activity, but also their action on the bladder afference, and therefore, on the reduction of the symptoms that constitute the syndrome. Beta-adrenergic agonists, which were recently added to the list of drugs for the treatment of overactive bladder, still wait for a definitive positioning - as either a second-line therapy or an adjuvant to oral anticholinergics. Conservative treatment failure, whether due to unsatisfactory results or the presence of adverse side effects, define it as refractory overactive bladder. In this context, the intravesical injection of botulinum toxin type A emerged as an effective option for the existing gap between the primary measures and more complex procedures such as bladder augmentation. Sacral neuromodulation, described three decades ago, had its indication reinforced in this overactive bladder era. Likewise, the electric stimulation of the tibial nerve is now a minimally invasive alternative to treat those with refractory overactive bladder. The results of the systematic literature review on the oral pharmacological treatment and the treatment of refractory overactive bladder gave rise to this second part of the review article Overactive Bladder - 18 years, prepared during the 1st Latin-American Consultation on Overactive Bladder.Univ Fed Sao Paulo, EPM, Sao Paulo, SP, BrazilUniv Sao Paulo, Dept Urol, BR-05508 Sao Paulo, SP, BrazilFac Med ABC, Dept Urol, Sao Paulo, SP, BrazilUniv Los Andes, Dept Urol, Bogota, ColombiaEscuela Med Mil, Dept Urol, Mexico City, DF, MexicoHosp Clin Jose San Martin, Catedra Urol, Buenos Aires, DF, ArgentinaMae de Deus Ctr Hosp, Dept Urol, Porto Alegre, RS, BrazilUniv Fed Ciencias Saude Porto Alegre, Porto Alegre, RS, BrazilAC Camargo Hosp, Dept Urol, Sao Paulo, SP, BrazilHosp Clinico Fuerza Area Chile, Santiago, ChileInst Mexicano Seguro Social, Mexico City, DF, MexicoHosp Souza Aguiar, Dept Urol, Rio De Janeiro, RJ, BrazilComplejo Med Policial Churruca Visca, Serv Urol, Buenos Aires, DF, ArgentinaCtr Policlin Valencia Vina, Valencia, VenezuelaHosp Pablo Tobon Uribe, Medellin, ColombiaClin Indisa, Serv Urol, Providencia, ChileCtr Reabilitacao & Readaptacao Dr Henriqe Santill, Goiania, Go, BrazilHosp Univ Caracas, Serv Urol, Caracas, VenezuelaUniv Fed Ceara, Div Urol, Fortaleza, Ceara, BrazilUniv Fed Sao Paulo, EPM, Sao Paulo, SP, BrazilWeb of Scienc

    Overactive bladder-18 years - Part I

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    Overactive bladder syndrome is one of the lower urinary tract dysfunctions with the highest number of scientific publications over the past two decades. This shows the growing interest in better understanding this syndrome, which gathers symptoms of urinary urgency and increased daytime and nighttime voiding frequency, with or without urinary incontinence and results in a negative impact on the quality of life of approximately one out of six individuals - including both genders and almost all age groups. The possibility of establishing the diagnosis just from clinical data made patients' access to specialized care easier. Physiotherapy resources have been incorporated into the urological daily practice. A number of more selective antimuscarinic drugs with consequent lower adverse event rates were released. Recently, a new class of oral drugs, beta-adrenergic agonists has become part of the armamentarium for Overactive Bladder. Botulinum toxin injections in the bladder and sacral neuromodulation are routine modalities of treatment for refractory cases. During the 1st Latin-American Consultation on Overactive Bladder, a comprehensive review of the literature related to the evolution of the concept, epidemiology, diagnosis, and management was conducted. This text corresponds to the first part of the review Overactive Bladder 18-years.Univ Fed Sao Paulo, EPM, Rua Dr Oscar Monteiro Barros 617-141, BR-05641010 Sao Paulo, SP, BrazilUniv Sao Paulo, Dept Urol, BR-05508 Sao Paulo, SP, BrazilFac Med ABC, Dept Urol, Sao Paulo, SP, BrazilUniv Los Andes, Dept Urol, Bogota, ColombiaEscuela Med, Dept Urol, Mexico City, DF, MexicoHosp Clin Jose San Martin, Catedra Urol, Buenos Aires, DF, ArgentinaMae de Deus Ctr Hosp, Dept Urol, Porto Alegre, RS, BrazilUniv Fed Ciencias Saude Porto Alegre, Porto Alegre, RS, BrazilAC Camargo Hosp, Dept Urol, Sao Paulo, BrazilHosp Clin Fuerza Area Chile, Santiago, ChileInst Mexicano Seguro Social, Mexico City, DF, MexicoHosp Souza Aguiar, Dept Urol, Rio De Janeiro, RJ, BrazilComplejo Med Policial Churruca Visca, Serv Urol, Buenos Aires, DF, ArgentinaCtr Policlin Valencia Vina, Valencia, VenezuelaHosp Pablo Tobon Uribe, Medellin, ColombiaClin Indisa, Serv Urol, Providencia, ChileCtr Reabilitacao & Readaptacao Dr Henriqe Santill, Goiania, Go, BrazilHosp Univ Caracas, Serv Urol, Caracas, VenezuelaUniv Fed Ceara, Div Urol, Fortaleza, Ceara, BrazilUniv Fed Sao Paulo, EPM, Rua Dr Oscar Monteiro Barros 617-141, BR-05641010 Sao Paulo, SP, BrazilWeb of Scienc

    Phosphofructo-1-Kinase Deficiency Leads to a Severe Cardiac and Hematological Disorder in Addition to Skeletal Muscle Glycogenosis

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    Mutations in the gene for muscle phosphofructo-1-kinase (PFKM), a key regulatory enzyme of glycolysis, cause Type VII glycogen storage disease (GSDVII). Clinical manifestations of the disease span from the severe infantile form, leading to death during childhood, to the classical form, which presents mainly with exercise intolerance. PFKM deficiency is considered as a skeletal muscle glycogenosis, but the relative contribution of altered glucose metabolism in other tissues to the pathogenesis of the disease is not fully understood. To elucidate this issue, we have generated mice deficient for PFKM (Pfkm−/−). Here, we show that Pfkm−/− mice had high lethality around weaning and reduced lifespan, because of the metabolic alterations. In skeletal muscle, including respiratory muscles, the lack of PFK activity blocked glycolysis and resulted in considerable glycogen storage and low ATP content. Although erythrocytes of Pfkm−/− mice preserved 50% of PFK activity, they showed strong reduction of 2,3-biphosphoglycerate concentrations and hemolysis, which was associated with compensatory reticulocytosis and splenomegaly. As a consequence of these haematological alterations, and of reduced PFK activity in the heart, Pfkm−/− mice developed cardiac hypertrophy with age. Taken together, these alterations resulted in muscle hypoxia and hypervascularization, impaired oxidative metabolism, fiber necrosis, and exercise intolerance. These results indicate that, in GSDVII, marked alterations in muscle bioenergetics and erythrocyte metabolism interact to produce a complex systemic disorder. Therefore, GSDVII is not simply a muscle glycogenosis, and Pfkm−/− mice constitute a unique model of GSDVII which may be useful for the design and assessment of new therapies

    Evaluating the association between artificial light-at-night exposure and breast and prostate cancer risk in Spain (MCC-Spain Study)

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    Background: Night shift work, exposure to light at night (ALAN) and circadian disruption may increase the risk of hormone-dependent cancers. Objectives: We evaluated the association of exposure to ALAN during sleeping time with breast and prostate cancer in a population based multicase–control study (MCC-Spain), among subjects who had never worked at night. We evaluated chronotype, a characteristic that may relate to adaptation to light at night. Methods: We enrolled 1,219 breast cancer cases, 1,385 female controls, 623 prostate cancer cases, and 879 male controls from 11 Spanish regions in 2008–2013. Indoor ALAN information was obtained through questionnaires. Outdoor ALAN was analyzed using images from the International Space Station (ISS) available for Barcelona and Madrid for 2012–2013, including data of remotely sensed upward light intensity and blue light spectrum information for each geocoded longest residence of each MCC-Spain subject. Results: Among Barcelona and Madrid participants with information on both indoor and outdoor ALAN, exposure to outdoor ALAN in the blue light spectrum was associated with breast cancer [adjusted odds ratio (OR) for highest vs. lowest tertile, OR=1.47 ; 95% CI: 1.00, 2.17] and prostate cancer (OR=2.05 ; 95% CI: 1.38, 3.03). In contrast, those exposed to the highest versus lowest intensity of outdoor ALAN were more likely to be controls than cases, particularly for prostate cancer. Compared with those who reported sleeping in total darkness, men who slept in “quite illuminated” bedrooms had a higher risk of prostate cancer (OR=2.79 ; 95% CI: 1.55, 5.04), whereas women had a slightly lower risk of breast cancer (OR=0.77 ; 95% CI: 0.39, 1.51). Conclusion: Both prostate and breast cancer were associated with high estimated exposure to outdoor ALAN in the blue-enriched light spectrum. https://doi.org/10.1289/EHP183
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