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Predicting the values of a financial time series is mainly a function of its price history, which depends on several factors, internal and external. With this history, it is possible to build an ∊-machine for predicting the financial time series. This work proposes considering the influence of a financial series through the transfer of entropy when the values of the other financial series are known. A method is proposed that considers the transfer of entropy for breaking the ties that occur when calculating the prediction with the ∊-machine. This analysis is carried out using data from six financial series: two American, the S&P 500 and the Nasdaq; two Asian, the Hang Seng and the Nikkei 225; and two European, the CAC 40 and the DAX. This work shows that it is possible to influence the prediction of the closing value of a series if the value of the influencing series is known. This work showed that the series that transfer the most information through entropy transfer are the American S&P 500 and Nasdaq, followed by the European DAX and CAC 40, and finally the Asian Nikkei 225 and Hang Seng.

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In most big cities, public transports are enclosed and crowded spaces. Therefore, they are considered as one of the most important triggers of COVID-19 spread. Most of the existing research related to the mobility of people and COVID-19 spread is focused on investigating highly frequented paths by analyzing data collected from mobile devices, which mainly refer to geo-positioning records. In contrast, this paper tackles the problem by studying mass mobility. The relations between daily mobility on public transport (subway or metro) in three big cities and mortality due to COVID-19 are investigated. Data collected for these purposes come from official sources, such as the web pages of the cities' local governments. To provide a systematic framework, we applied the IBM Foundational Methodology for Data Science to the epidemiological domain of this paper. Our analysis consists of moving averages with a moving window equal to seven days so as to avoid bias due to weekly tendencies. Among the main findings of this work are: a) New York City and Madrid show similar distribution on studied variables, which resemble a Gauss bell, in contrast to Mexico City, and b) Non-pharmaceutical interventions don't bring immediate results, and reductions to the number of deaths due to COVID are observed after a certain number of days. This paper yields partial evidence for assessing the effectiveness of public policies in mitigating the COVID-19 pandemic.

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BACKGROUND: Although a reliable procedure in morbid obesity treatment, bariatric surgery may be associated with serious complications such as leakage or bleeding. We aimed to analyze the preoperative factors involved in patients with early postoperative hemorrhage after any type of bariatric surgery who required conservative treatment or reoperation for this complication. METHODS: Retrospective case-controlled study (1:3) of 2 patient cohorts (postoperative bleeding/controls) matched by type of surgical intervention. RESULTS: Hypertension (Odds Ratio 5.029; 95% Confidence Interval 1.78-14.13) and history of antiplatelet medication (OR 13.263; 95% CI 1.39-125.9) were independent risk factors in the bivariate analyses, confirmed in the logistic regression model on multivariate analysis. CONCLUSIONS: With no between-group differences in Body Mass Index (BMI) and type 2 Diabetes (T2D), early hemorrhagic complications were found to be more frequent in patients with hypertension or antiplatelet drug treatment.

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Entropy is a key concept in the characterization of uncertainty for any given signal, and its extensions such as Spectral Entropy and Permutation Entropy. They have been used to measure the complexity of time series. However, these measures are subject to the discretization employed to study the states of the system, and identifying the relationship between complexity measures and the expected performance of the four selected forecasting methods that participate in the M4 Competition. This relationship allows the decision, in advance, of which algorithm is adequate. Therefore, in this paper, we found the relationships between entropy-based complexity framework and the forecasting error of four selected methods (Smyl, Theta, ARIMA, and ETS). Moreover, we present a framework extension based on the Emergence, Self-Organization, and Complexity paradigm. The experimentation with both synthetic and M4 Competition time series show that the feature space induced by complexities, visually constrains the forecasting method performance to specific regions; where the logarithm of its metric error is poorer, the Complexity based on the emergence and self-organization is maximal.

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In this paper we propose a criterion to balance the processing time and the solution quality of k-means cluster algorithms when applied to instances where the number n of objects is big. The majority of the known strategies aimed to improve the performance of k-means algorithms are related to the initialization or classification steps. In contrast, our criterion applies in the convergence step, namely, the process stops whenever the number of objects that change their assigned cluster at any iteration is lower than a given threshold. Through computer experimentation with synthetic and real instances, we found that a threshold close to 0.03n involves a decrease in computing time of about a factor 4/100, yielding solutions whose quality reduces by less than two percent. These findings naturally suggest the usefulness of our criterion in Big Data realms.

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Resumen Introducción: La fibrilación auricular es uno de los problemas de salud más importantes en el mundo por su elevada prevalencia, morbilidad y mortalidad, y porque es una causa importante de los ingresos hospitalarios y la principal indicación de la anticoagulación en atención primaria. Objetivo: El objetivo de nuestro estudio era definir el porcentaje de pacientes tratados, en la fibrilación auricular no valvular con anticoagulantes orales y las características clínicas de estos pacientes, calculando los riesgos embolígenos y hemorrágicos en este tipo de pacientes y su adecuación terapéutica. Pacientes y método: Estudio descriptivo, transversal y retrospectivo, pacientes de un centro de salud, de tres cupos de Atención Primaria con diagnóstico de fibrilación auricular no valvular. Variables: datos demográficos, antecedentes personales (hipertensión arterial, diabetes mellitus, dislipidemia, alcoholismo, tabaquismo, cardiopatía isquémica, insuficiencia cardiaca, enfermedad cerebrovascular, insuficiencia renal, arteriopatía periférica y embolia sistémica), cálculo de las escalas CHA2DS2-VASc y HAS-BLED. Resultados: Se encontraron 99 pacientes con fibrilación auricular no valvular de un total de 4.626 pacientes (2,15%). Edad media 77 ± 10 años, 52,5% mujeres y 47,5% hombres. El 33% no toma ningún tratamiento anticoagulante, el 53% toma el acenocumarol y el resto (13%) un Nuevo anticoagulante oral (dabigatran, apixaban o rivaroxaban). El 97% de los pacientes presentan CHA2DS2-VASc ≥ 2 (alto riesgo embolígeno), de los cuales el 30% no está tomando ningún tratamiento anticoagulante. El 80% de los pacientes presentan HAS-BLED ≥ 3 (alto riesgo hemorrágico), de los cuales el 55% toma el acenocumarol, presentando el 25% una razón internacional normalizada fuera de rango terapéutico. Conclusiones: La fibrilación auricular no valvular es una de las principales causas del accidente vascular cerebral en nuestros pacientes. Se demuestra que el tratamiento anticoagulante en aquellos pacientes con alto riesgo embolígeno reduce los eventos cerebrovasculares en un 64% y la mortalidad en un 26%. En nuestro medio la mayoría de los pacientes diagnosticados con fibrilación auricular no valvular presentan ese riesgo, pero tenemos un 33% no anticoagulado y un 25% mal controlado con el acenocumarol (un total del 46% de los pacientes). Todo esto implica que casi el 50% de nuestros pacientes con fibrilación auricular no valvular presenten alto riesgo tromboembólico por falta de tratamiento o ineficacia de este.

Abstract Introduction: Atrial fibrillation is one of the most important health problems in the world due to its high prevalence, morbidity and mortality, and because it is a frequent cause of hospital admission and the main indicator for anticoagulation therapy in primary care. Objective: The motivation of our study was to define the percentage of patients with nonvalvular atrial fibrillation treated with oral anticoagulants and their clinical characteristics, calculating risks for embolisms and bleeding in this type of patients and their appropriate therapeutic approach. Patients and methods: Descriptive, cross-sectional, retrospective study in patients of a primary care centre with three primary care quotas with a diagnosis of non-valvular atrial fibrillation. Variables: demographic data, personal history (arterial hypertension, diabetes mellitus, dyslipidemia, alcohol addiction, smoking habit, ischemic heart disease, heart failure, cerebrovascular disease, kidney failure, peripheral artery disease and systemic embolism), CHA2DS2-VASc and HAS-BLED scores. Results: Out of 4,626 patients, 99 (2.15%) were found to have nonvalvular atrial fibrillation. Average age 77 ± 10 years, 52.5% women and 47.5% men. 33% are not receiving any anticoa- gulation therapy, 53% takes acenocoumarol and the rest (13%) a new oral blood-thinning drug (dabigatran, apixaban or rivaroxaban). 97% of patients present a CHA2DS2-VASc ≥2 risk (high for embolism), of which 30% are not receiving any anticoagulation therapy. 80% of patients present HAS-BLED ≥ 3 risk (high for bleeding), of which 55% is taking acenocoumarol, 25% showing international normalized ratio out of the therapeutic range. Conclusion: Nonvalvular atrial fibrillation is one of the main causes of cerebrovascular accidents in our patients. It is shown that anticoagulation therapy in patients with high risk of embolism reduces cerebrovascular accidents by 64% and mortality by 26%. In our field, most patients diagnoses with nonvalvular atrial fibrillation have this risk, but 33% are not taking anticoagulants and 25% are poorly controlled with acenocoumarol (a total of 46% of patients). All this implies that 50% of our patients with non-valvular atrial fibrillation develop a high risk for thromboembolic events due to lack or inadequacy of the treatment.

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RNA metabolism is a critical but frequently overlooked control element affecting virtually every cellular process in bacteria. RNA processing and degradation is mediated by a suite of ribonucleases having distinct cleavage and substrate specificity. Here, we probe the role of two ribonucleases (RNase III and RNase J) in the emerging model system Streptomyces venezuelae. We show that each enzyme makes a unique contribution to the growth and development of S. venezuelae and further affects the secondary metabolism and antibiotic production of this bacterium. We demonstrate a connection between the action of these ribonucleases and translation, with both enzymes being required for the formation of functional ribosomes. RNase III mutants in particular fail to properly process 23S rRNA, form fewer 70S ribosomes, and show reduced translational processivity. The loss of either RNase III or RNase J additionally led to the appearance of a new ribosomal species (the 100S ribosome dimer) during exponential growth and dramatically sensitized these mutants to a range of antibiotics.

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In August 2007 an outbreak of neurological disease and sudden death in Arabian horses occurred in a farm located in Coronel Rosales County, Buenos Aires Province, Argentina. The animals were on a pasture of native grasses and supplemented ad libitum with corn kernels and wheat bran. Three horses were observed having acute neurologic signs including blindness, four leg ataxia, hyperexcitability, aimless walking and circling, followed by death in two of them. Four other horses were found dead overnight without a history of neurologic signs. The morbidity, mortality and lethality rates were 11.6 percent, 10 percent and 85.7 percent, respectively. Grossly, the brain showed focal areas of hemorrhage, brown-yellow discoloration and softening of the sub-cortical white matter. The microscopic brain lesions consisted of extensive areas of malacia within the white matter of the cerebral hemispheres, brainstem and cerebellum, characterized by rarefaction of the white matter with cavitations filled with proteinaceous edema, multifocal hemorrhages and mild infiltration by neutrophils, and rare eosinophils. Swollen glial cells with abundant eosinophilic cytoplasm, distinct cell borders, intracytoplasmic deeply eosinophilic globules and eccentric, hyperchromatic, occasionally pyknotic nucleus were present throughout the areas of rarefaction hemorrhage, edema and necrosis. The feed supplements contained 12,490µg/kg of fumonisin B1 and 5,251µg/ kg of fumonisin B2. This is the first reported outbreak of ELEM associated with consumption of feed supplements containing high concentrations of fumonisins in Argentina.(AU)

Em agosto de 2007, ocorreu um surto de doença neurológica e morte súbita em cavalos árabes em uma propriedade localizada no município de Coronel Rosales, na província de Buenos Aires, Argentina. Os animais estavam em pasto nativo e eram suplementados ad libitum com grãos de milho e farelo de trigo. Três cavalos foram observados com sinais neurológicos agudos, incluindo cegueira, ataxia nas quatro pernas, hiperexcitabilidade, e andar sem rumo e em círculo, seguidos de morte em dois animais. Outros quatro cavalos foram encontrados mortos durante a noite sem histórico de distúrbios neurológicos. A mortalidade, morbidade e letalidade foram de 11,6 por cento, 10 por cento e 85,7 por cento, respectivamente. Macroscopicamente, o cérebro tinha áreas focais de hemorragia, coloração amarelada e amolecimento da substância branca sub-cortical. Microscopicamente, as lesões cerebrais consistiram de extensas áreas de malácia na substância branca dos hemisférios cerebrais, do tronco encefálico e do cerebelo. Estas lesões da substância branca se caracterizaram por rarefação, cavidades contendo fluido proteináceo (edema), hemorragias multifocais e moderado infiltrado por neutrófilos e raros eosinófilos. Células gliais tumefeitas com abundante citoplasma eosinifílico, limites celulares evidentes, globules citoplasmáticos eosinofílicos, e núcleo excéntrico, hipercromático e ocasionalmente picnótico foram observadas nas areas de rarefacção, edema, hemorragias e necrose. Os suplementos alimentares continham 12.490µg/kg de fumonisina B1 e 5.251µg/ kg de fumonisina B2. Este é o primeiro surto reportado na Argentina de leucoencefalomalácia equina associado ao consumo de suplementos alimentares contendo altas concentrações de fumonisinas.(AU)

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In August 2007 an outbreak of neurological disease and sudden death in Arabian horses occurred in a farm located in Coronel Rosales County, Buenos Aires Province, Argentina. The animals were on a pasture of native grasses and supplemented ad libitum with corn kernels and wheat bran. Three horses were observed having acute neurologic signs including blindness, four leg ataxia, hyperexcitability, aimless walking and circling, followed by death in two of them. Four other horses were found dead overnight without a history of neurologic signs. The morbidity, mortality and lethality rates were 11.6 percent, 10 percent and 85.7 percent, respectively. Grossly, the brain showed focal areas of hemorrhage, brown-yellow discoloration and softening of the sub-cortical white matter. The microscopic brain lesions consisted of extensive areas of malacia within the white matter of the cerebral hemispheres, brainstem and cerebellum, characterized by rarefaction of the white matter with cavitations filled with proteinaceous edema, multifocal hemorrhages and mild infiltration by neutrophils, and rare eosinophils. Swollen glial cells with abundant eosinophilic cytoplasm, distinct cell borders, intracytoplasmic deeply eosinophilic globules and eccentric, hyperchromatic, occasionally pyknotic nucleus were present throughout the areas of rarefaction hemorrhage, edema and necrosis. The feed supplements contained 12,490µg/kg of fumonisin B1 and 5,251µg/ kg of fumonisin B2. This is the first reported outbreak of ELEM associated with consumption of feed supplements containing high concentrations of fumonisins in Argentina.

Em agosto de 2007, ocorreu um surto de doença neurológica e morte súbita em cavalos árabes em uma propriedade localizada no município de Coronel Rosales, na província de Buenos Aires, Argentina. Os animais estavam em pasto nativo e eram suplementados ad libitum com grãos de milho e farelo de trigo. Três cavalos foram observados com sinais neurológicos agudos, incluindo cegueira, ataxia nas quatro pernas, hiperexcitabilidade, e andar sem rumo e em círculo, seguidos de morte em dois animais. Outros quatro cavalos foram encontrados mortos durante a noite sem histórico de distúrbios neurológicos. A mortalidade, morbidade e letalidade foram de 11,6 por cento, 10 por cento e 85,7 por cento, respectivamente. Macroscopicamente, o cérebro tinha áreas focais de hemorragia, coloração amarelada e amolecimento da substância branca sub-cortical. Microscopicamente, as lesões cerebrais consistiram de extensas áreas de malácia na substância branca dos hemisférios cerebrais, do tronco encefálico e do cerebelo. Estas lesões da substância branca se caracterizaram por rarefação, cavidades contendo fluido proteináceo (edema), hemorragias multifocais e moderado infiltrado por neutrófilos e raros eosinófilos. Células gliais tumefeitas com abundante citoplasma eosinifílico, limites celulares evidentes, globules citoplasmáticos eosinofílicos, e núcleo excéntrico, hipercromático e ocasionalmente picnótico foram observadas nas areas de rarefacção, edema, hemorragias e necrose. Os suplementos alimentares continham 12.490µg/kg de fumonisina B1 e 5.251µg/ kg de fumonisina B2. Este é o primeiro surto reportado na Argentina de leucoencefalomalácia equina associado ao consumo de suplementos alimentares contendo altas concentrações de fumonisinas.

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Protein disulfide isomerase (PDI) enzymes are eukaryotic oxidoreductases that catalyze the correct formation of disulfide bonds during protein folding. Structurally they are characterized by the presence of functional thioredoxin-like (Trx) domains. For the protozoan parasite causative of the human amebiasis (Entamoeba histolytica), the correct formation of disulfide bonds is important for an accurate folding of its proteins, including some virulence factors. However, little is known about the enzymes involved in this mechanism. We undertook a post-genomic approach to identify the PDI family of this parasite. The genome database survey revealed a set of 11 PDI-encoding sequences with predictable protein thiol/disulfide oxidoreductase activities.

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