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The subject of this study is the microcredit market in the USA, more specifically in Florida. The justification for choosing this specific state is the massive presence of the Hispanic population. This will facilitate a generalization of the obtained results to the microcredit market in Latin American countries. Thus, the objective of this study is to analyze the profile of microcredit holders and their companies from socioeconomic and financial points of view. As our data also consider the degree of repayment of the microloans included in the sample, the clients' profile is related to the punctuality or default of their corresponding loan repayments using the methodology of multinomial logit regression. The variables used in this study refer to personal information concerning borrowers (gender, age, education level, and marital status), the economic situation of their respective companies (closeness to the lender, number of workers, and revenues), and the characteristics of granted loans (principal, term, and purpose). However, the results of the regression show that only two variables are significant at the 5% significance level: the borrower's age, which has a positive effect on repayment punctuality, and the loan term, which exhibits a negative effect. The findings of this study have clear implications, as they can help lenders design suitable microloans adjusted to customer profiles. Finally, future research should include other demographics and characteristics of affected companies.

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There is broad consensus supporting the reciprocal influence of working memory (WM) and attention. Top-down mechanisms operate to cope with either environmental or internal demands. In that sense, it is possible to select an item within the contents of WM to endow it with prioritized access. Although evidence supports that maintaining an item in this privileged state does not rely on sustained visual attention, it is unknown whether selection within WM depends on perceptual attention. To answer this question, we recorded electrophysiological neural activity while participants performed a retro-cue task in which we inserted a detection task in the delay period after retro-cue presentation. Critically, the onset of to-be-detected near threshold stimuli was unpredictable, and thus, sustained perceptual spatial attention was needed to accomplish the detection task from the offset of the retro-cue. At a behavioral level, we found decreased visual detection when a WM representation was retro-cued. At a neural level, alpha oscillatory activity confirmed a spatial shift of attention to the retro-cued representation. We interpret the convergence of neural oscillations and behavioral data to point towards the theory that selection within WM could be accomplished through a perceptual attentional mechanism.

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It has been proposed that alpha oscillations reflect the endogenous modulation of visual cortex excitability. In particular, alpha power increases during the maintenance period in Working Memory (WM) tasks have been interpreted as a mechanism to avoid potential interference of incoming stimuli. In this study we tested whether alpha power was modulated during the maintenance of WM to enhance the processing of relevant incoming perceptual stimuli. To this aim, we manipulated the contrast of a stimulus presented during the maintenance period of a WM task. The to-be-detected stimulus could indicate which of the encoded representations was going to be probed after the delay (spatial retro-cue) or could signal that all the representations had equal probability to be tested (neutral retro-cue). Time-frequency analysis revealed that alpha power preceding retro-cue presentation was not differently modulated by the two different contrast conditions. This is, participants did not endogenously modulate alpha oscillations upon low perceptual contrast stimuli incoming. These results suggest that alpha delay activity is not a goal directed mechanism to control the inflow of information during WM maintenance. Instead, current data suggest that alpha delayed activity might be an index of increased allocation of attentional resources to the processing of the WM representations.

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Visuospatial working memory (WM) requires the activity of a spread network, including right parietal regions, to sustain storage capacity, attentional deployment, and active manipulation of information. Notably, while the electrophysiological correlates of such regions have been explored using many different indices, evidence for a functional involvement of the individual frequency peaks in the alpha (IAF) and theta bands (ITF) is still poor despite their relevance in many influential theories regarding WM. Interestingly, there is also a parallel lack of literature about the effect of short-term practice on WM performance. Here, we aim to clarify whether the simple repetition of a change-detection task might be beneficial to WM performance and to which degree these effects could be predicted by IAF and ITF. For this purpose, 25 healthy participants performed a change-detection task at baseline and in a retest session, while IAF and ITF were also measured. Results show that task repetition improves WM performance. In addition, right parietal IAF, but not ITF, accounts for performance gain such that faster IAF predicts higher performance gain. Our findings align with recent literature suggesting that the faster the posterior alpha, the finer the perceptual sampling rate, and the higher the WM performance gain.

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Investment decisions rely on perceptions from external stimuli along with the integration of inner brain-body signals, all of which are shaped by experience. As experience is capable of molding both the structure and function of the human brain, we have used a novel neuroimaging connectomic-genetic approach to investigate the influence of investment work experience on brain anatomy. We found that senior investors display higher gray matter volume and increased structural brain connectivity in dopamine-related pathways, as well as a set of genes functionally associated with adrenaline and noradrenaline biosynthesis (SLC6A3, TH and SLC18A2), which is seemingly involved in reward processing and bodily stress responses during financial trading. These results suggest the key role of catecholamines in the way senior investors harness their emotions while raising bodily awareness as they grow in investment maturity.

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It is claimed that investment decision-making should rely on rational analyses based on facts and not emotions. However, trying to make money out of market forecasts can trigger all types of emotional responses. As the question on how investors decide remains controversial, we carried out an activation likelihood estimation (ALE) meta-analysis using functional magnetic resonance imaging (fMRI) studies that have reported whole-brain analyses on subjects performing an investment task. We identified the ventral striatum, anterior insula, amygdala and anterior cingulate cortex as being involved in this decision-making process. These regions are limbic-related structures which respond to reward, risk and emotional conflict. Our findings support the notion that investment choices are emotional decisions that take into account market information, individual preferences and beliefs.

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Low back pain is one the most common forms of musculoskeletal disorders. Thus, several physiotherapeutic strategies (e.g., global postural re-education therapy) have been used for reducing low back pain. The aim of this study was to determinate if acute application of global postural re-education session associated effects are influenced by the time-of-day when this physical therapy is applied. Eight participants in a randomized, counterbalanced order were acutely tested both before and 24 h after a global postural re-education therapy session (10 min session) in three different time-of-day points; morning (i.e., AM; 7:00-9:00 h), midday (i.e., AM; 12:00-14:00 h) and afternoon (i.e., PM; 18:00-20:00 h). In each session, low back pain Visual Analogue Pain Scale [VAS]), flexibility, function capacity (Roland Morris Questionnaire [RMQ], and physical functioning Oswestry Disability Index [ODI]) were recorded. Results showed a pain reduction (VAS Scale) 24 h post Global postural re-education [GPR] session (p = 0.001) and increasing of flexibility pre-post GPR session in all the time-of-day points (morning, midday, and afternoon) (p = 0.001) while no differences were reported in RMQ (p = 0.969) and ODI (p = 0.767). Thus, acute GPR session produces the same effects on flexibility, low back pain, function capacity, and physical functioning values independently of time-of-day when it is applied.

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BACKGROUND: Acute respiratory infections are the leading cause of childhood mortality. The lack of physicians in rural areas of developing countries makes difficult their correct diagnosis and treatment. The staff of rural health facilities (health-care technicians) may not be qualified to distinguish respiratory diseases by auscultation. For this reason, the goal of this project is the development of a tele-stethoscopy system that allows a physician to receive real-time cardio-respiratory sounds from a remote auscultation, as well as video images showing where the technician is placing the stethoscope on the patient's body. METHODS: A real-time wireless stethoscopy system was designed. The initial requirements were: 1) The system must send audio and video synchronously over IP networks, not requiring an Internet connection; 2) It must preserve the quality of cardiorespiratory sounds, allowing to adapt the binaural pieces and the chestpiece of standard stethoscopes, and; 3) Cardiorespiratory sounds should be recordable at both sides of the communication. In order to verify the diagnostic capacity of the system, a clinical validation with eight specialists has been designed. In a preliminary test, twelve patients have been auscultated by all the physicians using the tele-stethoscopy system, versus a local auscultation using traditional stethoscope. The system must allow listen the cardiac (systolic and diastolic murmurs, gallop sound, arrhythmias) and respiratory (rhonchi, rales and crepitations, wheeze, diminished and bronchial breath sounds, pleural friction rub) sounds. RESULTS: The design, development and initial validation of the real-time wireless tele-stethoscopy system are described in detail. The system was conceived from scratch as open-source, low-cost and designed in such a way that many universities and small local companies in developing countries may manufacture it. Only free open-source software has been used in order to minimize manufacturing costs and look for alliances to support its improvement and adaptation. The microcontroller firmware code, the computer software code and the PCB schematics are available for free download in a subversion repository hosted in SourceForge. CONCLUSIONS: It has been shown that real-time tele-stethoscopy, together with a videoconference system that allows a remote specialist to oversee the auscultation, may be a very helpful tool in rural areas of developing countries.

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Se estudiaron 96 pacientes de 3 años, ingresados en el Servicio de Neurología Pediátrica de nuestro Centro, con diagnóstico de epilepsia, con el objetivo de evaluar la aplicación de la clasificación de los ataques, la de Epilepsia y Síndromes de Epilépticos aceptados actualmente por la Liga Internacional Contra la Epilepsia (ILAE). En ellos se observó con mayor frecuencia la presentación de ataques parciales (58,3 por ciento), seguido de los generalizados (36,5 por ciento) e indeterminados (5 por ciento); no se presentaron diferencias significativas respecto a la distribución de éstos entre menores de 1 año y los comprendidos en edades entre 1 y 3 años. En 28 pacientes se encontraron dificultades para clasificarlos acorde con la de Epilepsia y Síndromes Epilépticos, y se analizaron su distribución y características. Se comentan brevemente los resultados del electroencefalograma (EEG) en relación con la actividad paroxística y se presentan los síndromes más frecuentemente observados(AU)

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Se estudiaron 96 pacientes de 3 anos, ingresados en el Servicio de Neurologia Pediatrica de nuestro Centro, con diagnostico de epilepsia, con el objetivo de evaluar la aplicacion de la clasificacion de los ataques, la de Epilepsia y Sindromes de Epilepticos aceptados actualmente por la Liga Internacional Contra la Epilepsia (ILAE). En ellos se observo con mayor frecuencia la presentacion de ataques parciales (58,3 por ciento), seguido de los generalizados (36,5 por ciento) e indeterminados (5 por ciento); no se presentaron diferencias significativas respecto a la distribucion de estos entre menores de 1 ano y los comprendidos en edades entre 1 y 3 anos. En 28 pacientes se encontraron dificultades para clasificarlos acorde con la de Epilepsia y Sindromes Epilepticos, y se analizaron su distribucion y caracteristicas. Se comentan brevemente los resultados del electroencefalograma (EEG) en relacion con la actividad paroxistica y se presentan los sindromes mas frecuentemente observados

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Se reportan los 2 prieros casos de acidemia propiónica diagnosticados en Cuba. Se analizaron muestras de orina de ambos pacientes, en relación con metabolitos secundarios del propionil CoA, mediante cromotografía gaseosa-espectrometría de masas. Se detectó en ambos pacientes un patrón de metabolitos urinarios de la enfermedad, apesar de haber observado un amplio rango de varición. Se concluye que, los ácidos 2-metil,3cetovalérico y el metilcítrico deben considerarse de gran valor diagnóstico

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Se reportan los 2 prieros casos de acidemia propiónica diagnosticados en Cuba. Se analizaron muestras de orina de ambos pacientes, en relación con metabolitos secundarios del propionil CoA, mediante cromotografía gaseosa-espectrometría de masas. Se detectó en ambos pacientes un patrón de metabolitos urinarios de la enfermedad, apesar de haber observado un amplio rango de varición. Se concluye que, los ácidos 2-metil,3cetovalérico y el metilcítrico deben considerarse de gran valor diagnóstico

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Se reporta el caso de una niña de 18 meses de edad que presenta características fenotípicas de tipo "hurleroide, a la cual se le realizó la determinación de las enzimas relacionadas con el metabolismo de los mucopolisacáridos (MPS), así como la caracterización cinética de la enzima denominada alfa-L-iduronidasa, cuya deficiencia condujo al diagnóstico de dicha enfermedad

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Se reporta el caso de una niña de 18 meses de edad que presenta características fenotípicas de tipo "hurleroide, a la cual se le realizó la determinación de las enzimas relacionadas con el metabolismo de los mucopolisacáridos (MPS), así como la caracterización cinética de la enzima denominada alfa-L-iduronidasa, cuya deficiencia condujo al diagnóstico de dicha enfermedad

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Se discuten los problemas más frecuentes en el diagnóstico de la fenilcetonuria. Se hace una breve revisión histórica de los principales descubrimientos y evolución sobre los conceptos de la fenilcetonuria, una de las anomalias congénitas del metabolismo que está siendo pesquisada en masa en nuestro país. A partir de la década del 70 se descubren variantes de la enfermedad, en las cuales los signos neurológicos y el retraso mental persistian y aun empeoraban, a pesar del tratamiento dietético adecuado. Se clasifican todos los casos de fenilcetonuria en 3 grandes grupos: 1. La fenilcetonuria clásica 2. La hiperfenilalaninemia 3. Las variantes por defecto de los cofactores (coenzima). Se ofrece la clasificación de varias formas de la enfermedad, según Mayer la describió en el año 1986. Para comprender los problemas que plantea el diagnóstico y tratamiento actual de este trastorno metabólico, se presenta un estudio más detallado de los defectos de los cofactores (coenzimas). Se concluye citando al propio Mayer: "Actualmente no es posible hacer un pesquisaje en masa para detectar la fenilcetonuria en el recién nacido e iniciar un tratamiento adecuado basado solamente en los niveles en sangre de la fenilalanina

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Se discuten los problemas más frecuentes en el diagnóstico de la fenilcetonuria. Se hace una breve revisión histórica de los principales descubrimientos y evolución sobre los conceptos de la fenilcetonuria, una de las anomalias congénitas del metabolismo que está siendo pesquisada en masa en nuestro país. A partir de la década del 70 se descubren variantes de la enfermedad, en las cuales los signos neurológicos y el retraso mental persistian y aun empeoraban, a pesar del tratamiento dietético adecuado. Se clasifican todos los casos de fenilcetonuria en 3 grandes grupos: 1. La fenilcetonuria clásica 2. La hiperfenilalaninemia 3. Las variantes por defecto de los cofactores (coenzima). Se ofrece la clasificación de varias formas de la enfermedad, según Mayer la describió en el año 1986. Para comprender los problemas que plantea el diagnóstico y tratamiento actual de este trastorno metabólico, se presenta un estudio más detallado de los defectos de los cofactores (coenzimas). Se concluye citando al propio Mayer: "Actualmente no es posible hacer un pesquisaje en masa para detectar la fenilcetonuria en el recién nacido e iniciar un tratamiento adecuado basado solamente en los niveles en sangre de la fenilalanina

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Se exponen los nuevos conceptos y las tendencias actuales en el tratamiento de las epilepsias: se hace una amplia revisión de los mecanismos de acción de las drogas antiepilépticas más comúnmente usadas. Se ofrecen los lineamientos básicos para el manejo del niño epiléptico, particularmente cuando debe indicarse el tratamiento anticonvulsivante, la selección de la droga o las combinaciones de ellas y las indicaciones en cada caso. Se considera que uno de los avances más notables en la terapéutica y manejo de la epilepsia es la introducción de métodos confiables para la determinación de los niveles séricos de los anticonvulsivantes. Se subraya el valor de la monoterapia como proceder terapéutico que une a las ventajas de alta eficacia una incidencia muy baja de efectos adversos

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Se exponen los nuevos conceptos y las tendencias actuales en el tratamiento de las epilepsias: se hace una amplia revisión de los mecanismos de acción de las drogas antiepilépticas más comúnmente usadas. Se ofrecen los lineamientos básicos para el manejo del niño epiléptico, particularmente cuando debe indicarse el tratamiento anticonvulsivante, la selección de la droga o las combinaciones de ellas y las indicaciones en cada caso. Se considera que uno de los avances más notables en la terapéutica y manejo de la epilepsia es la introducción de métodos confiables para la determinación de los niveles séricos de los anticonvulsivantes. Se subraya el valor de la monoterapia como proceder terapéutico que une a las ventajas de alta eficacia una incidencia muy baja de efectos adversos

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