RESUMEN: El pollo doméstico es una especie de ave que ha sido ampliamente estudiada en cuanto a su biología y como organismo modelo para la ciencia. La reproducción de la especie es por la puesta de huevos fecundados, que en un período de 21 días desarrollarán un polluelo en su interior. Se han descrito varios métodos para desarrollar embriones ex-ovo, permitiendo la observación y manipulación del organismo. Este trabajo tuvo como objetivo estandarizar un método que permita el desarrollo de los embriones dentro del sistema de incubación artificial, el cual tiene un bajo costo y es fácil de realizar. En este trabajo se utilizaron 100 huevos de gallina para estudiar los efectos de la humedad, la suplementación mineral y el tiempo de preincubación del huevo sobre la incubación ex-ovo de los embriones. El desarrollo embrionario se documentó a través de los diferentes días. Se seleccionó la cáscara de huevo pulverizada como una fuente óptima para proporcionar calcio, magnesio, fósforo y otros minerales al embrión en desarrollo. Al suministrar 900-1200 mg de cáscara de huevo pulverizada, 40 mL de la solución de cloruro de benzalconio al 0.001 % y un tiempo de preincubación de aproximadamente 56 h, los embriones lograron desarrollarse hasta los 19 días, y aunque no llegaron a eclosionar, los embriones lograron desarrollarse hasta los 19 días. Se lograron condiciones de incubación que permitieron la supervivencia y desarrollo de los embriones hasta etapas tardías. Así, debido a las condiciones establecidas de calcio, humedad y tiempo de preincubación, en el presente trabajo los pollitos alcanzaron los 19 días de desarrollo.

SUMMARY: The domestic chicken is a species of bird that has been extensively studied in regard to its biology and as a model organism for science. The reproduction of the species is by the laying of fertilized eggs, which in a period of 21 days will develop a chick inside. Several methods have been described to develop embryos ex-ovo, allowing the observation and manipulation of the organism. This work has the propose to standardize a method that allows the development of the embryos inside the artificial incubation system, which has a low cost and is easy to make. In this work, 100 chicken eggs were used to study the effects of humidity, mineral supplementation, and the preincubation time of the egg on the incubation ex-ovo of the embryos. Embryo development was documented through the different days. Pulverized eggshell was selected as an optimal source to provide calcium, magnesium, phosphorus, and other minerals to the developing embryo. By providing 900-1200 mg of pulverized eggshell, 40 mL of the 0.001 % solution of benzalkonium chloride, and a preincubation time of approximately 56 h, the embryos were able to develop until 19 days, and even though they did not reach hatching, the incubation conditions that allowed the survival and development of embryos until late stages were achieved. Thus, due to the conditions established for calcium, humidity and preincubation time, in the present work, the chicks reached 19 days of development.

RESUMEN La COVID-19 es una enfermedad infecciosa ocasionada por el virus SARS-CoV-2. La propagación de este virus se produce principalmente a través de gotitas liberadas por la nariz o la boca de una persona infectada. Aunque se han desarrollado vacunas que permiten reducir efectivamente los efectos que esta infección viral provoca, el método más eficaz para contener la propagación del virus son las numerosas pruebas para detectar y aislar los posibles portadores. Sin embargo, el tiempo de respuesta, combinado con el costo de las pruebas reales, hace que esta opción sea poco práctica. Aquí, comparamos algunas metodologías de machine learning para proponer una estrategia confiable para detectar personas positivas a COVID-19 analizando espectros de saliva obtenidos por espectroscopia infrarroja transformada de Fourier (FTIR). Tras analizar 1275 espectros, con 7 estrategias comúnmente empleadas en el área de machine learning, concluimos que un modelo de regresión lineal multivariante (MLMR) resulta ser la mejor opción para identificar posibles infectados. De acuerdo con nuestros resultados, el desplazamiento observado en la región de la amida I del espectro, resulta fundamental y confiable para establecer una frontera a partir del cambio de pendiente que este provoca. Al ser más ágil y económica que la reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR), podría aplicarse confiablemente como estrategia preliminar a RT-PCR.

ABSTRACT COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. This virus's spread is mainly through droplets released from the nose or mouth of an infected person. Although vaccines have been developed that effectively reduce the effects that this viral infection causes, the most effective method to contain the virus’s spread is numerous tests to detect and isolate possible carriers. However, the response time, combined with the cost of actual tests, makes this option impractical. Herein, we compare some machine learning methodologies to propose a reliable strategy to detect people positive to COVID-19, analyzing saliva spectra obtained by Fourier transform infrared (FTIR) spectroscopy. After analyzing 1275 spectra, with 7 strategies commonly used in machine learning, we concluded that a multivariate linear regression model (MLMR) turns out to be the best option to identify possible infected persons. According to our results, the displacement observed in the region of the amide I of the spectrum, is fundamental and reliable to establish a border from the change in slope that causes this displacement that allows us to characterize the carriers of the virus. Being more agile and cheaper than reverse transcriptase polymerase chain reaction (RT-PCR), it could be reliably applied as a preliminary strategy to RT-PCR.

Abstract: This study investigates the relationship between the phenomenon known as El Niño-Southern Oscillation, characterized by the ENSO Multivariate Index, and the annual precipitation around Mexico City. The spatial and temporal behavior of precipitation during the 1950-2010 period was also assessed, revealing that during the period mentioned the annual mean precipitation does not show a linear trend, but a variation with a single cycle only. Contingency tables and the Chi-square test were used to reject the hypothesis of independence between precipitation and ENSO. In addition, the bootstrap resampling technique showed that negative ENSO phases reduce precipitation in the Mexico City area; the neutral phase increases precipitation and lowers the probability that precipitation be below the median value. During the positive phase, precipitation is not significantly affected.

Resumen: Se estudia la relación que existe entre el Fenómeno de El Niño-Oscilación del Sur, caracterizado por el Índice Multivariado del ENOS, y la precipitación en la Ciudad de México en escala anual. Se estudia también su comportamiento espacial y temporal durante el periodo 1950-2010 encontrándose que en el periodo de estudio el promedio anual de la lluvia no presenta tendencia lineal pero si un ciclo de variación. Se usan tablas de contingencia y la prueba Ji-cuadrada para rechazar la hipótesis de independencia entre la precipitación y el fenómeno ENOS. Además, se utilizó la técnica de remuestreo de bootstrap, encontrando que la fase negativa de ENOS disminuye la precipitación en la Ciudad de México; la fase neutra aumenta la precipitación y disminuye la probabilidad de que la precipitación sea inferior al valor mediano. Durante la fase positiva, la precipitación no se ve significativamente afectada.

RESUMO Relatamos um caso de cegueira cortical secundário à síndrome de leucoencefalopatia posterior recuperado pelo controle bem sucedido da pressão arterial. Um homem branco de 66 anos de idade compareceu à emergência com queixa de dor de cabeça frontal severa, desorientação e embaçamento progressivo da visão. O exame físico inicial revelou uma pressão arterial de 200/176 mmHg. Uma hora depois, o paciente apresentou confusão mental e cegueira bilateral. Após a tomografia e a ressonância nuclear magnética, o tratamento sistêmico foram realizados e o diagnóstico de síndrome da leucoencefalopatia posterior foi realizado. A síndrome de leucoencefalopatia posterior é uma manifestação rara de hipertensão sistêmica que requer um diagnóstico e gerenciamento adequados para evitar danos cerebrais irreversíveis. O reconhecimento precoce desta condição e o controle imediato da pressão arterial são essenciais porque podem levar à reversão da síndrome, o que, de outra forma, pode resultar em dano cerebral permanente.

ABSTRACT We report a case of cortical blindness secondary to posterior leukoencephalopathy syndrome, which was successfully treated by blood pressure management. A 66-year-old white man presented at the emergency room complaining of severe frontal headache, disorientation, and progressive blurred vision. The initial physical examination disclosed a blood pressure of 200/176 mmHg. One hour later the patient exhibited mental confusion and bilateral blindness. Computed tomography and magnetic resonance imaging were performed, and a systemic workup was conducted, resulting in a diagnosis of posterior leukoencephalopathy syndrome. This syndrome is a rare manifestation of systemic hypertension that requires proper diagnosis and management to avoid irreversible brain damage. Early recognition of this condition and prompt control of the patient’s blood pressure are essential because they may bring about a reversal of the syndrome, which may otherwise result in permanent brain damage.

Abstract Piecewise-linear models constitute an attractive alternative to construct a function whose graph fits a finite set of discrete points. These models are preferably selected over other approximation strategies like polynomials or splines. Although there are several piecewise-linear models reported in literature, the so-called High Level Canonical has the remarkable advantage of emerging from a well-structured algorithmic methodology to efficiently determine the parameters of any given piecewise-linear function. However, as it happens in all other piecewise-linear models, it also has the problem of lack of differentiability at the breakpoints. In order to solve this problem, an approach based on an exponential approximation of the basis-function is proposed as a strategy to transform the High Level Canonical piecewise-linear model into a smooth-piecewise one. This mathematical transformation ensures the existence and continuity of the nth-order derivatives of the resulting smooth model. Besides of this, it is observed that by applying the piecewise-linear to smooth transformation, the number of terms of the resulting smooth representation can significantly be reduced due to a great number of them can be approximated by a line equation. In order to verify the effectiveness of this proposal, numerical simulations performed on one-dimensional and two-dimensional functions are reported.

América Latina e Caribe (ALC) têm instalações e profissionais treinados para diagnosticar, tratar e apoiar as pessoas com demência e outras formas de comprometimento cognitivo limitado. A situação para as pessoas com demência é pobre, e piora quando a proporção de idosos na população em geral está se expandindo rapidamente. Revisamos as iniciativas já existentes, com exemplos de medidas tomadas para fortalecer a capacidade e melhorar a eficácia dos indivíduos, organizações e sistemas nacionais que fornecem tratamento e apoio às pessoas com demência e seus cuidadores. As barreiras regionais ao reforço das capacidades e a importância do engajamento público são realçados. Os programas existentes precisam divulgar seus objetivos, realizações, limitações e lições globais aprendidas a fim de obter maior reconhecimento da necessidade de programas de capacitação.

Latin America and the Caribbean (LAC) have limited facilities and professionals trained to diagnose, treat, and support people with dementia and other forms of cognitive impairment. The situation for people with dementia is poor, and worsening as the proportion of elderly in the general population is rapidly expanding. We reviewed existing initiatives and provided examples of actions taken to build capacity and improve the effectiveness of individuals, organizations, and national systems that provide treatment and support for people with dementia and their caregivers. Regional barriers to capacity building and the importance of public engagement are highlighted. Existing programs need to disseminate their objectives, accomplishments, limitations, and overall lessons learned in order to gain greater recognition of the need for capacity-building programs.

At CEILAP (CITEDEF-CONICET), a multiangle Raman lidar is under development to monitor aerosol extinction in the frame of the CTA (Cherenkov Telescope Array) Project. This is an initiative to build the next generation of ground-based instruments to collect very high energy gamma-ray radiation. It will serve as an open observatory for a wide astrophysics community and will explore the Universe in depth in Very High Energy (> 10 GeV) gamma-rays. The atmospheric conditions are is a major interest for CTA, and this instrument plays a major role measuring the atmospheric optical depth. The reception system is made by six 40 cm in diameter Newtonian telescopes, totally exposed to the hard environmental condition during the shifts. These working conditions could produce misalignments between laser and telescopes, losing the required overlap. To avoid that, a telescope controlled by a self-alignment system is under development to solve this problem. This is performed by PC software running from the acquisition module which is connected via ethernet to a microcontroller. This paper, describes the self-alignment method and hardware work in progress.