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Background: The standard configuration's set of twelve electrocardiogram (ECG) leads is optimal for the medical diagnosis of diverse cardiac conditions. However, it requires ten electrodes on the patient's limbs and chest, which is uncomfortable and cumbersome. Interlead conversion methods can reconstruct missing leads and enable more comfortable acquisitions, including in wearable devices, while still allowing for adequate diagnoses. Currently, methodologies for interlead ECG conversion either require multiple reference (input) leads and/or require input signals to be temporally aligned considering the ECG landmarks.Methods: Unlike the methods in the literature, this paper studies the possibility of converting ECG signals into all twelve standard configuration leads using signal segments from only one reference lead, without temporal alignment (blindly-segmented). The proposed methodology is based on a deep learning encoder-decoder U-Net architecture, which is compared with adaptations based on convolutional autoencoders and label refinement networks. Moreover, the method is explored for conversion with one single shared encoder or multiple individual encoders for each lead.Results: Despite the more challenging settings, the proposed methodology was able to attain state-of-the-art level performance in multiple target leads, and both lead I and lead II seem especially suitable to convert certain sets of leads. In cross-database tests, the methodology offered promising results despite acquisition setup differences. Furthermore, results show that the presence of medical conditions does not have a considerable effect on the method's performance.Conclusions: This study shows the feasibility of converting ECG signals using single-lead blindly-segmented inputs. Although the results are promising, further efforts should be devoted towards the improvement of the methodologies, especially the robustness to diverse acquisition setups, in order to be applicable to cardiac health monitoring in wearable devices and less obtrusive clinical scenarios. [ABSTRACT FROM AUTHOR]

Patients affected by L- 2-hydroxyglutaric aciduria (L-2-HGA) are biochemically characterized by elevated L- 2-hydroxyglutaric acid (L-2-HG) concentrations in cerebrospinal fluid, plasma, and urine due to a blockage in the conversion of L-2-HG to α-ketoglutaric acid. Neurological symptoms associated with basal ganglia and cerebelar abnormalities whose pathophysiology is still unknown are typical of this neurometabolic disorder. In the present study we evaluated the early effects (30 min after injection) of an acute in vivo intrastriatal and intracerebellar L-2-HG administration on redox homeostasis in rat striatum and cerebellum, respectively. Histological analyses of these brain structures were also carried out 7 days after L-2-HG treatment (long-term effects). L-2-HG significantly decreased the concentrations of reduced (GSH) and total glutathione (tGS), as well as of glutathione peroxidase (GPx) and reductase (GR) activities, but did not change the activities of superoxide dismutase and catalase in striatum. Furthermore, the concentrations of oxidized glutathione (GSSG) and malondialdehyde (MDA), as well as 2′,7′-dichlorofluorescein (DCFH) oxidation and hydrogen peroxide (H 2 O 2 ) production, were increased, whereas carbonyl formation and nitrate plus nitrite concentrations were not altered by L-2-HG injection. It was also found that the melatonin, ascorbic acid plus α-tocopherol, and creatine totally prevented most of these effects, whereas N- acetylcysteine, the noncompetitive glutamate NMDA antagonist MK-801, and the nitric oxide synthase inhibitor L-NAME were not able to normalize the redox alterations elicited by L-2-HG in striatum. L-2-HG intracerebellar injection similarly provoked a decrease of antioxidant defenses (GSH, tGS, GPx, and GR) and an increase of the concentrations of GSSG, MDA, and H 2 O 2 in cerebellum. These results strongly indicate that the major accumulating metabolite in L-2-HGA induce oxidative stress by decreasing the antioxidant defenses and enhancing reactive oxygen species in striatum and cerebellum of adolescent rats. Regarding the histopathological findings, L-2-HG caused intense vacuolation, lymphocyte and macrophage infiltrates, eosinophilic granular bodies, and necrosis in striatum. Immunohistochemistry revealed that L-2-HG treatment provoked an increase of GFAP and a decrease of NeuN immunostaining, indicating reactive astroglyosis and reduction of neuronal population, respectively, in striatum. Similar macrophage infiltrates, associated with less intense vacuolation and lymphocytic infiltration, were observed in cerebellum. However, we did not observe necrosis, eosinophilic granular bodies, and alteration of GFAP and NeuN content in L-2-HG-teated cerebellum. From the biochemical and histological findings, it is presumed that L-2-HG provokes striatal and cerebellar damage in vivo possibly through oxidative stress induction. Therefore, we postulate that antioxidants may serve as adjuvant therapy allied to the current treatment based on a protein-restricted diet and riboflavin and L- carnitine supplementation in patients affected by L-2-HGA. [ABSTRACT FROM AUTHOR]

Throughout the 20th century, several thinkers noticed that Technology was becoming a global phenomenon. More recently, US geologist Peter Haff claimed that a Technosphere is now in place and can be conceived as a new Earth geological system. This unprecedented situation is creating enormous challenges not only for our species, since more and more of its members are now dependent on the subsistence of this man-made sphere, but also for other species and natural ecosystems that have become increasingly dependent on it. Perhaps the most crucial of these challenges is the sustainability of the Technosphere itself. In the first part of the article, I attempted a critical reconstruction of Haff's Technosphere concept. The second part is dedicated to analyzing how the unsustainability of the Technosphere represents a global catastrophic risk and ultimately an existential risk. [ABSTRACT FROM AUTHOR]

The research study presented herein evaluates the corrosion behaviour of the reinforcing steel in blended concretes using two pozzolanic additives—metakaolin (MK) and silica fume (SF)—at 10% replacement of cement weight. They are exposed to CO 2 and chlorides. The corrosion process was followed by monitoring of open-circuit potential (OCP), polarisation resistance (Rp) and electrochemical impedance spectroscopy (EIS). Electrochemical measurements show that the addition of MK and SF enhances corrosion resistance exposed to chlorides, however under accelerated carbonation these concretes show higher corrosion rates. In the simultaneous exposition to carbon dioxide and chlorides, SF-concrete shows a decrease of corrosion rate. [ABSTRACT FROM AUTHOR]

The weight excess and chronic diseases related it constitutes one of the main current social problems. This study intends to investigate and to discuss an individual's training seeking to take him/it to the maxim use of fats in the metabolism. Will the aerobic training based on the values of R between 0,70 and 0,84 take the individual to the largest fat use as source of energy for the exercise and to a considerable loss of corporal fat? We believed in the social and scientific relevance of this study, since most of the adults is sedentary and it presents at least a risk factor for cardiovascular diseases. The case study was used, based on the data collected in indirect calorimetry test and defined a training of eight weeks, 60 minutes for session, six days a week, heart rate among 58 to 66% of maximum heart rate, tends as goal larger fat use as energy source, without intervention in the alimentary diet. Among the obtained results we can detach loss of 6.20 kg of corporal mass. We concluded that the results of the study are promising, because the proposed training acted positively so much in the corporal composition, as in the physical conditioning, as in the metabolism of plasmatic lipids. [ABSTRACT FROM AUTHOR]

Biometric recognition and presentation attack detection (PAD) methods strongly rely on deep learning algorithms. Though often more accurate, these models operate as complex black boxes. Interpretability tools are now being used to delve deeper into the operation of these methods, which is why this work advocates their integration in the PAD scenario. Building upon previous work, a face PAD model based on convolutional neural networks was implemented and evaluated both through traditional PAD metrics and with interpretability tools. An evaluation on the stability of the explanations obtained from testing models with attacks known and unknown in the learning step is made. To overcome the limitations of direct comparison, a suitable representation of the explanations is constructed to quantify how much two explanations differ from each other. From the point of view of interpretability, the results obtained in intra and inter class comparisons led to the conclusion that the presence of more attacks during training has a positive effect in the generalisation and robustness of the models. This is an exploratory study that confirms the urge to establish new approaches in biometrics that incorporate interpretability tools. Moreover, there is a need for methodologies to assess and compare the quality of explanations. [ABSTRACT FROM AUTHOR]

The objective of this research was to obtain an estimation of the leaf area of Tectonas grandis L. f. By means of linear dimensional parameters of the leaves. From August of 2015 to September of 2016, 354 leaf limbs were collected from the middle third of the canopy of three tecales trees located in Capitão Poço, Irituia and Garrafão do Norte, located in the micro region of Pará. Leaf area was determined by the disc method. Linear, linear, nonintercept, quadratic, cubic, logarithmic, exponential and potential linear models were determined, considering the actual leaf area as a dependent variable and length (C), width (L), sum (C+L) and the product of (C x L) of each leaf limb as independent variables, eliminating the models that presented a determination coefficient less than 0.90. Pearson's correlation coefficient (r), determination (R2), root mean square error (RQME), mean absolute error (EAM) of Willmott and the CS index. The models that best fit the data were: the potential 0.0464 (C + L)2,2397, the linear without intercept 0.4449(CxL), and the quadratic, 0001 (CxL)2 + 0,2573 (CxL) + 98,2606. The linear equation without intercept considering (CxL) was the one that presented the best performance to estimate the teak leaf area (Tectonas Grandis L. f). [ABSTRACT FROM AUTHOR]

Research on minors' mental health is an increasingly developing area. Given the increased prevalence of disorders, it seems necessary to analyze the factors that can affect poor mental health. This study analyzes the influence of occupational class, educational level, age, sex and perceived mental health of Spanish children, which is measured through the Strengths and Difficulties Questionnaire. The sample consists of 3599 minors between 4 and 14 years old, who were interviewed through the Spanish National Health Survey 2011. Our results indicating the significant (p < 0.05) relationship between mental health, occupational class (OR 0.533) and minors' health in the last year (OR 0.313) are shown. However, gender (OR 1.187) and educational level of Pre-School Education in relation to Secondary Education (OR 1.174) and Primary Education (OR 0.996) do not generate significant differences. In conclusion, we consider it necessary to design and implement public policies aimed at improving the care system for children who have had poor or regular health in the last year, and whose parents are positioned in the lowest part of the occupational scale. [ABSTRACT FROM AUTHOR]

Renal failure due to leukemic infiltration of kidney in chronic lymphocytic leukemia is an extremely rare condition. The authors report a case of a 59-year-old white female, with a past medical history of chronic lymphocytic leukemia (CLL) with 2 years of evolution without medical therapy, admitted with nonoliguric acute renal failure needing dialysis. Renal biopsy showed extensive small lymphocytes' infiltration in the cortical interstitium by CLL cells. Cyclophosphamide and prednisolone were started and 1 month later changed to fludarabine plus cyclophosphamide with improvement of renal function. Although renal failure due to leukemic infiltration has been described in many cases of acute leukemia, only 11 cases of renal failure due to CLL cells' infiltration have been described in the literature. Renal histology is an extremely important tool to confirm diagnosis. [ABSTRACT FROM AUTHOR]