[Identification and antifungal activity of halophilic bacteria isolated from saline soils in Campeche, México]. / Identificación y actividad antifúngica de bacterias halófilas aisladas de suelos salinos en Campeche, México.

Phytopathogenic fungi Alternaria alternata and Colletotrichum gloeosporioides cause diseases in plant tissues as well as significant postharvest losses. The use of chemical fungicides for their control has negative effects on health and the environment. Secondary metabolites from halophilic bacteria are a promising alternative for new antifungal compounds. In the present study, halophilic bacteria were isolated and characterized from two sites with saline soils called branquizales in Campeche, Mexico. A total of 64 bacteria were isolated. Agrobacterium, Bacillus, Inquilinus, Gracilibacillus, Metabacillus, Neobacillus, Paenibacillus, Priestia, Staphylococcus, Streptomyces and Virgibacillus were among the identified genera. The antifungal potential of the culture supernatant (CS) of 39 halophilic bacteria was investigated against C. gloeosporioides and A. alternata. The bacteria showing the greatest inhibition of mycelial growth corresponded to Bacillus subtilis CPO 4292, Metabacillus sp. CPO 4266, Bacillus sp. CPO 4295 and Bacillus sp. CPO 4279. The CS of Bacillus sp. CPO 4279 exhibited the highest activity and its ethyl acetate extract (AcOEt) inhibited the germination of C. gloeosporioides, with IC50 values of 8,630µg/ml and IC90 of 10,720µg/ml. The organic partition of the AcOEt extract led to three fractions, with acetonitrile (FAcB9) showing the highest antifungal activity, with values exceeding 66%. Halophilic bacteria from 'blanquizales' soils of the genus Bacillus sp. produce metabolites with antifungal properties that inhibit the phytopathogenic fungus C. gloeosporioides.

Physical and respiratory therapy in the critically ill patient with obesity: a narrative review.

Obesity has become increasingly prevalent in the intensive care unit, presenting a significant challenge for healthcare systems and professionals, including rehabilitation teams. Caring for critically ill patients with obesity involves addressing complex issues. Despite the well-established and safe practice of early mobilization during critical illness, in rehabilitation matters, the diverse clinical disturbances and scenarios within the obese patient population necessitate a comprehensive understanding. This includes recognizing the importance of metabolic support, both non-invasive and invasive ventilatory support, and their weaning processes as essential prerequisites. Physiotherapists, working collaboratively with a multidisciplinary team, play a crucial role in ensuring proper assessment and functional rehabilitation in the critical care setting. This review aims to provide critical insights into the key management and rehabilitation principles for obese patients in the intensive care unit.

Prolonged intensive care: muscular functional, and nutritional insights from the COVID-19 pandemic.

During the coronavirus disease 2019 (COVID-19) pandemic, clinical staff learned how to manage patients enduring extended stays in an intensive care unit (ICU). COVID-19 patients requiring critical care in an ICU face a high risk of experiencing prolonged intensive care (PIC). The use of invasive mechanical ventilation in individuals with severe acute respiratory distress syndrome can cause numerous complications that influence both short-term and long-term morbidity and mortality. Those risks underscore the importance of proactively addressing functional complications. Mitigating secondary complications unrelated to the primary pathology of admission is imperative in minimizing the risk of PIC. Therefore, incorporating strategies to do that into daily ICU practice for both COVID-19 patients and those critically ill from other conditions is significantly important.

Effect of Epsilon-Near-Zero Modes on the Casimir Interaction between Ultrathin Films.

Vacuum fluctuation-induced interactions between macroscopic metallic objects result in an attractive force between them, a phenomenon known as the Casimir effect. This force is the result of both plasmonic and photonic modes. For very thin films, field penetration through the films will modify the allowed modes. Here, we theoretically investigate the Casimir interaction between ultrathin films from the perspective of force distribution over real frequencies for the first time. Pronounced repulsive contributions to the force are found due to the highly confined and nearly dispersion-free epsilon-near-zero (ENZ) modes that only exist in ultrathin films. These contributions persistently occur around the ENZ frequency of the film irrespective of the interfilm separation. We further associate the ENZ modes with a striking thickness dependence of a proposed figure of merit (FOM) for conductive thin films, suggesting that the motion of objects induced by Casimir interactions is boosted for deeply nanoscale sizes. Our results shed light on the correlation between special electromagnetic modes and the vacuum fluctuation-induced force as well as the resulting mechanical properties of ultrathin ENZ materials, which may create new opportunities for engineering the motion of ultrasmall objects in nanomechanical systems.

Awake prone positioning and oxygen therapy in patients with COVID-19: the APRONOX study.

BACKGROUND: The awake prone positioning strategy for patients with acute respiratory distress syndrome is a safe, simple and cost-effective technique used to improve hypoxaemia. We aimed to evaluate intubation and mortality risk in patients with coronavirus disease 2019 (COVID-19) who underwent awake prone positioning during hospitalisation. METHODS: In this retrospective, multicentre observational study conducted between 1 May 2020 and 12 June 2020 in 27 hospitals in Mexico and Ecuador, nonintubated patients with COVID-19 managed with awake prone or awake supine positioning were included to evaluate intubation and mortality risk through logistic regression models; multivariable and centre adjustment, propensity score analyses, and E-values were calculated to limit confounding. RESULTS: 827 nonintubated patients with COVID-19 in the awake prone (n=505) and awake supine (n=322) groups were included for analysis. Fewer patients in the awake prone group required endotracheal intubation (23.6% versus 40.4%) or died (19.8% versus 37.3%). Awake prone positioning was a protective factor for intubation even after multivariable adjustment (OR 0.35, 95% CI 0.24-0.52; p<0.0001, E=2.12), which prevailed after propensity score analysis (OR 0.41, 95% CI 0.27-0.62; p<0.0001, E=1.86) and mortality (adjusted OR 0.38, 95% CI 0.26-0.55; p<0.0001, E=2.03). The main variables associated with intubation among awake prone patients were increasing age, lower baseline peripheral arterial oxygen saturation/inspiratory oxygen fraction ratio (P aO2 /F IO2 ) and management with a nonrebreather mask. CONCLUSIONS: Awake prone positioning in hospitalised nonintubated patients with COVID-19 is associated with a lower risk of intubation and mortality.

Aplicaciones e implicaciones de la pausa al final de la inspiración en ventilación mecánica / Applications and implications of end-inspiratory pause in mechanical ventilation / Aplicações e implicações da pausa ao final da inspiração na ventilação mecânica

Resumen: El uso de la pausa al final de la inspiración (PFI) en ventilación mecánica data de hace más de 50 años y con mayor impulso en la década de los 70, se le atribuye una mejoría en la presión parcial de oxígeno arterial (PaO2) al incrementar la presión media de la vía aérea (Pma), mayor aclaramiento de la presión parcial de dióxido de carbono arterial (PaCO2) y permite la monitorización de la presión meseta (Pmeseta) en la mecánica ventilatoria; sin embargo, los estudios clínicos sobre su uso son escasos y controversiales. En este artículo se abordan los mecanismos fisiológicos, fisiopatológicos y la evidencia sobre el uso de la PFI en ventilación mecánica (VM).

Abstract: The use of the end inspiratory pause (EIP) in mechanical ventilation has been going on for more than 50 years and with greater momentum in the 1970s, an improvement in the partial pressure of arterial oxygen (PaO2) is attributed to the increase mean airway pressure, greater clearance of partial pressure of arterial carbon dioxide and allows monitoring of plateau pressure in ventilatory mechanics; However, the Clinical studies on its use are few and controversial. This article addresses the physiological and pathophysiological mechanisms and the evidence on the use of EIP in mechanical ventilation.

Resumo: A utilização da pausa ao final da inspiração (PFI) na ventilação mecânica remonta a mais de 50 anos e com maior impulso na década de 70, atribui-se uma melhora na pressão parcial de oxigênio arterial (PaO2) pelo aumento da pressão média das vias aéreas (Pma), uma maior depuração da pressão parcial de dióxido de carbono arterial (PaCO2) e permite a monitorização da pressão de platô (Pplateau) na mecânica ventilatória, porém estudos Os dados clínicos sobre seu uso são escassos e controversos. Este artigo aborda os mecanismos fisiológicos e fisiopatológicos e as evidências sobre o uso do PFI na ventilação mecânica (VM).

Engineered l-Lactate Responding Promoter System Operating in Glucose-Rich and Anoxic Environments.

Bacteria equipped with genetically encoded lactate biosensors are promising tools for biopharmaceutical production, diagnostics, and cellular therapies. However, many applications involve glucose-rich and anoxic environments, in which current whole-cell lactate biosensors show low performance. Here we engineer an optimized, synthetic lactate biosensor system by repurposing the natural LldPRD promoter regulated by the LldR transcriptional regulator. We removed glucose catabolite and anoxic repression by designing a hybrid promoter, containing LldR operators and tuned both regulator and reporter gene expressions to optimize biosensor signal-to-noise ratio. The resulting lactate biosensor, termed ALPaGA (A Lactate Promoter Operating in Glucose and Anoxia), can operate in glucose-rich, aerobic and anoxic conditions. We show that ALPaGA works reliably in the probiotic chassisEscherichia coliNissle 1917 and can detect endogenous l-lactate produced by 3D tumor spheroids with an improved dynamic range. In the future, the ALPaGA system could be used to monitor bioproduction processes and improve the specificity of engineered bacterial cancer therapies by restricting their activity to the lactate-rich microenvironment of solid tumors.

Efectos de espaciamientos sobre el crecimiento y rendimiento del fríjol caupí cultivar Caupicor 50 / Effects of spacings on the growth and yield of cowpea beans cultivar Caupicor 50

RESUMEN El fríjol caupí es una leguminosa importante en la región Caribe de Colombia, por su contribución a la dieta de sus pobladores y por ser una alternativa de ingresos para pequeños productores; sin embargo, los rendimientos obtenidos no superan los 600 kg ha-1, debido al desconocimiento del efecto de las prácticas culturales en la especie, como en los diversos cultivares. El objetivo del estudio fue evaluar el efecto de diferentes espaciamientos e hidrogel sobre características vegetativas y reproductivas del fríjol caupí cultivar Caupicor 50, en el departamento de Sucre, del Caribe colombiano. Se utilizó el diseño experimental parcelas sub-subdivididas, con tres repeticiones (bloques). Se combinaron dos distancias entre hileras: 60 y 80 cm en la parcela principal, tres distancias entre plantas: 20, 30 y 40 cm en la subparcela e hidrogel: 0 y 5 g/planta en la sub-subparcela. Las variables evaluadas fueron: altura de planta, área foliar, índice de área foliar, tasa de crecimiento del cultivo, número de vainas/planta, longitud de vaina, número de semillas/vaina, peso de cien semillas y rendimiento de semillas/ha. El mayor rendimiento, se estimó con 20 cm entre plantas y 60 cm entre hileras (83.333 plantas ha-1), con un rendimiento de 2.027 kg ha-1, asociado a mayor área foliar, índice de área foliar y tasa de crecimiento del cultivo y, a menor número de vainas por planta, longitud de vaina y peso de cien semillas.

ABSTRACT Cowpea bean is an important legume in the Caribbean region of Colombia, for its contribution to the diet of its habitants and being an alternative income for small producers. Nevertheless, the yields obtained do not exceed 600 kg ha-1, due to the unknown of the effect of cultural methods on the species, as in the different cultivars. The purpose of the study was to evaluate the effect of different spacing and hydrogel on vegetative and reproductive characteristics of cowpea beans, cultivar Caupicor 50 in the department of Sucre of the Caribbean region of Colombia. A split-plot design was used, with three replications (blocks). Two distances between rows: 60 and 80 cm in the main plot, three spaces between plants: 20, 30, and 40 cm in the subplot, and hydrogel: 0 and 5 g / plant in the sub-sub plot were combined. The variables evaluated were: plant height, leaf area, leaf area index, crop growth rate, number of pods per plant, pod length, number of seeds per pod, the weight of one hundred seed, and seed yield/ha. The highest yield, 2,027 kg ha-1, was estimated with 20 cm between plants and 60 cm between rows (83,333 plants ha-1) and was associated with greater leaf area, leaf area index and crop growth rate, and a lower number of pods per plant, pod length and weight of one hundred seeds.

Evaluación de fuentes de variación en pruebas multi-ambientes para rendimiento y sus componentes en algodón / Evaluation of sources of variation in multi-environment tests for yield and its components in cotton

RESUMEN La valoración de las fuentes de variación de los análisis de varianza combinado en las pruebas de evaluación multi-ambientes es de gran importancia en la selección de genotipos para recomendar nuevos cultivares, por su adaptabilidad y estabilidad. El objetivo de esta investigación fue evaluar la significancia estadística y contribución de las fuentes de variación: ambientes, genotipos e interacción genotipo x ambiente para rendimiento de algodón-semilla, porcentaje de fibra y rendimiento de fibra, en las zonas del Caribe seco y húmedo colombiano. Se utilizaron los datos de dos pruebas multi-ambientes por zona, donde se evaluaron 10 genotipos de fibra media diferentes, bajo el diseño de bloques completos al azar, con cuatro repeticiones. Cada prueba estuvo conformada por cuatro ensayos realizados durante las cosechas 2003/2004, 2007/2008 y 2009/2010. Los resultados señalan que, en promedio, el ambiente fue la fuente de variación más importante en significancia (p <0,05 y p <0,01) y variación (>64 %), de los análisis de varianza combinado para rendimiento de algodón-semilla y fibra, con tendencia similar en su comportamiento entre ellas y en las dos zonas del Caribe colombiano. Para el porcentaje de fibra en el Caribe seco, la fuente de variación más importante fue genotipos (74,4 %) y en el Caribe húmedo fue el ambiente (57,2 %). Se sugiere subdividir las dos zonas del Caribe en subzonas más homogéneas ambientalmente o aumentar en más de cuatro el número de ensayos por prueba, para minimizar el efecto del ambiente y la interacción genotipo x ambiente.

ABSTRACT The assessment of the sources of variation of the combined analysis of variance in the multi-environment evaluation tests is of great importance in the selection of genotypes to recommend new cultivars for their adaptability and stability. The objective of this research was to evaluate the statistical significance and contribution of the sources of variation: environments, genotypes and genotype x environment interaction for cotton-seed yield, fiber percentage and fiber yield, in the dry and humid Colombian Caribbean zones. Data from two multi-environment tests per zone were used, where 10 different medium fiber genotypes were evaluated, under a randomized complete block design with four replications. Each test consisted of four experimentos carried out during the 2003/2004, 2007/2008 and 2009/2010 harvests. The results indicate that on average the environment was the most important source of variation in significance (p <0.05 and p <0.01) and variation (>64 %) of the combined analysis of variance for cotton-seed yield and fiber, with a similar trend in their behavior between them and in the two zones of the Colombian Caribbean. For the percentage of fiber in the dry Caribbean, the most important source of variation was genotypes (74.4 %) and in the humid Caribbean it was the environment (57.2 %). It is suggested to subdivide the two zones of the Caribbean into more environmentally homogeneous subzones and / or to increase the number of trials per test, to minimize the effect of the environment and the genotype x environment interaction.

PARÁMETROS GENÉTICOS DE CARACTERÍSTICAS BIOMÉTRICAS DEL FRUTO Y SEMILLA EN Caesalpinia ébano (FABACEAE) / Genetic parameters of fruit and seed biometric characteristics in Caesalpinia ebano (Fabaceae)

RESUMEN El objetivo del estudio fue evaluar los parámetros genéticos de las características biométricas del fruto y semillas de Caesalpinia ebano. La investigación se realizó en Montería (Colombia), se seleccionaron diez árboles, y de cada uno diez frutos tomados al azar. Se realizaron análisis de varianza y estimación de parámetros genéticos para nueve características: peso fresco del fruto, largo del fruto, ancho del fruto, grosor del fruto, número de semillas/fruto, peso de semillas por fruto, peso de una semilla, volumen de una semilla y densidad de una semilla. Se detectaron diferencias estadísticas (p < 0,01) entre árboles, para todas las características, excepto para el ancho del fruto y peso de una semilla; denotando la existencia de variabilidad genética entre los árboles para peso del fruto, largo del fruto, grosor del fruto, número de semillas y densidad de una semilla. El peso y largo del fruto presentaron la heredabilidad media familiar y heredabilidad en el sentido estricto con los valores más altos (h2 Fam > 82 % y h2 E > 30 %). La ganancia genética esperada fue mayor del 10 % en cinco de las nueve características estudiadas, y mayor del 20 % para número de semillas y peso de las semillas (27,31 y 27,87 %, respectivamente). Los caracteres peso y largo del fruto se podrían transmitir a las generaciones sucesivas, con mayor posibilidad de éxito, mediante la selección fenotípica de árboles.

ABSTRACT The objective of the study was to evaluate the genetic parameters of the biometric characteristics of the fruit and seeds of C. ebano. The investigation was carried out in Montería, Córdoba (Colombia); ten trees were selected and from each, ten fruits taken at random. Variance analysis and estimation of genetic parameters for nine traits were carried out: fresh fruit weight, fruit length, fruit width, fruit thickness, number of seeds/fruit, weight of seeds by fruit, weight of one seed, volume of one seed and density of one seed. Statistical differences (p < 0.01) were detected between trees, for all traits except for width of the fruit and weight of a seed; denoting the existence of genetic variability between trees for fruit weight, fruit length, fruit thickness, number of seeds and density of a seed. The weight and length of the fruit presented the highest family heritability and narrow sense heritability (h2 Fam > 82 % and h2 E> 30 %). The expected genetic gain was greater than 10 % in five of the nine studied traits, and greater than 20 % for number of seeds and weight of seeds (27.31 and 27.87 %, respectively). The traits fruit weight and length could be transmitted to successive generations, with greater chance of success, by phenotypic selection of trees.

The Role of TCF7L2 in Type 2 Diabetes.

TCF7L2 is the most potent locus for type 2 diabetes (T2D) risk and the first locus to have been robustly reported by genomic linkage studies. TCF7L2 is a transcription factor that forms a basic part of the Wnt signaling pathway. This gene has highly conserved sequence regions that correspond to functional domains. The association of TCF7L2 with T2D is one of the most powerful genetically discovered in studies of complex diseases, as it has been consistently replicated in multiple populations with diverse genetic origins. The mechanisms over which TCF7L2 exerts its effect on T2D are still not well understood. In this article, we describe the main molecular mechanisms of how TCF7L2 is related to T2D. TCF7L2 variants associated with T2D risk exert an influence on the initial therapeutic success of the hypoglycemic oral agent sulfonylurea. Thus, it is important to know whether there are other TCF7L2 variants associated with T2D that can influence treatment with oral hypoglycemic agents. Resequencing of the TCF7L2 gene in diverse ethnic groups is required to reveal common and rare variations and their role in different pathologies and in adverse reactions to drugs. Identification of TCF7L2-susceptibility disease variants will permit, at a given moment, offering of therapies to patients according to their genotype.

Movilización temprana en la Unidad de Cuidados Intensivos / Early mobilization in the Intensive Care Unit / Mobilização precoce na Unidade de Terapia Intensiva

Resumen: La movilización temprana (MT) es la implementación de ejercicio físico en los pacientes ingresados en la Unidad de Cuidados Intensivos (UCI) observándose beneficios importantes como reducción de neumonías asociadas con ventilación mecánica (NAVM), trombosis venosa profunda, úlceras por presión, debilidad adquirida en la UCI (DAUCI). Además, tiene un impacto financiero al reducir los días de estancia hospitalaria y en la UCI. Cabe mencionar que la MT impacta en el desenlace posterior al alta hospitalaria reduciendo la aparición de síndrome postcuidados intensivos (PICS).

Abstract: Early mobilization (EM) is the implementation of physical exercise in patients admitted to the Intensive Care Unit (ICU), with important benefits being observed such as reduction of ventilator-associated pneumonia, deep vein thrombosis, pressure ulcers and ICU-acquired weakness (ICU-AW). It also has a financial impact by reducing hospital length of stay and in the ICU. Also, EM has an important role in the outcome once the patient leaves the hospital reducing the post-intensive care syndrome (PICS).

Resumo: A mobilização precoce (MP) é a implementação de exercícios físicos em pacientes internados em Unidade de Terapia Intensiva (UTI), observando benefícios importantes como redução da pneumonia associada à ventilação mecânica (PAV), trombose venosa profunda, úlceras por pressão, fraqueza adquirida no UTI (DAUCI). Além disso, tem impacto financeiro ao reduzir os dias de internação e internação na UTI. Vale ressaltar que a MT tem impacto no desfecho após a alta hospitalar por reduzir o aparecimento da Síndrome de Terapia Pós-Intensiva (PICS).

A single inverse-designed photonic structure that performs parallel computing.

In the search for improved computational capabilities, conventional microelectronic computers are facing various problems arising from the miniaturization and concentration of active electronics. Therefore, researchers have explored wave systems, such as photonic or quantum devices, for solving mathematical problems at higher speeds and larger capacities. However, previous devices have not fully exploited the linearity of the wave equation, which as we show here, allows for the simultaneous parallel solution of several independent mathematical problems within the same device. Here we demonstrate that a transmissive cavity filled with a judiciously tailored dielectric distribution and embedded in a multi-frequency feedback loop can calculate the solutions of a number of mathematical problems simultaneously. We design, build, and test a computing structure at microwave frequencies that solves two independent integral equations with any two arbitrary inputs and also provide numerical results for the calculation of the inverse of four 5 x 5 matrices.

Superovulatory response and embryo quality in Boer does following dietary supplementation with different sources of omega-3 and omega-6 fatty acids during the breeding season.

The purpose of this study was to determine effects of various sources of omega-3 and omega-6 fatty acids on ovarian response and embryo quality in Boer does when there was a superovulation treatment regimen imposed. Pluriparous does were randomly assigned to be treated with 300 g of one of four experimental supplements containing linseed oil (LO), soybean oil (SO), palm oil (PO), or a control supplement without fatty acids (CO), for 15 days. Does were fitted with a controlled internal drug release (CIDR) device containing 0.3 g progesterone for 7 days. At 48 h before CIDR withdrawal, does were treated with 80 mg follicle-stimulating hormone (FSH) administered at 12 h intervals. Embryos were collected 7 days after the last natural mating. Estrous response and interval between CIDR withdrawals to estrous onset were similar between treatments (P > 0.05). Number of ovulations was similar for does in the different groups (10.0, 9.2, 7.0, and 7.0, in LO, SO, PO, and CO, respectively; P > 0.05). There was premature luteal regression in does of the SO, PO, and CO groups, except in LO group. The LO-treated does had a larger (P < 0.05) mean number of ova/embryos recovered than does of SO, PO, and CO groups (7.2, 2.0, 0.2, 0.2, respectively) and transferable embryos (5.1, 1.4, 0.2, 0.2, respectively). These results indicate that including LO in supplements may be a feasible strategy for preventing premature luteal regression and improving embryo quality in goats treated to induce follicular super-stimulation for induction of superovulation.

Asymmetric surface wave excitation through metasurface-edge diffraction.

The selective excitation of localized surface wave modes remains a challenge in the design of both leaky-wave and bound-wave devices. In this Letter, we show how the truncation of a metasurface can play an important role in breaking the spatial inversion symmetry in the excitation of surface waves supported by the structure. This is done by combining a large anisotropy in the dispersion relation and the presence of an edge that also serves as a coupling mechanism between the plane wave excitation and the induced surface waves. By resorting to the exact solution to the scattering problem based on a discrete Wiener-Hopf technique, we show that by inverting the component of the impinging wavevector parallel to the truncation, two distinct surface waves are excited.

Rational programming of history-dependent logic in cellular populations.

Genetic programs operating in a history-dependent fashion are ubiquitous in nature and govern sophisticated processes such as development and differentiation. The ability to systematically and predictably encode such programs would advance the engineering of synthetic organisms and ecosystems with rich signal processing abilities. Here we implement robust, scalable history-dependent programs by distributing the computational labor across a cellular population. Our design is based on standardized recombinase-driven DNA scaffolds expressing different genes according to the order of occurrence of inputs. These multicellular computing systems are highly modular, do not require cell-cell communication channels, and any program can be built by differential composition of strains containing well-characterized logic scaffolds. We developed automated workflows that researchers can use to streamline program design and optimization. We anticipate that the history-dependent programs presented here will support many applications using cellular populations for material engineering, biomanufacturing and healthcare.

¿Ha cambiado el paradigma de la prevención del ictus en los pacientes con diabetes? / Has the paradigm of stroke prevention changed in patients with diabetes?

No disponible

Achieving asymmetry and trapping in diffusion with spatiotemporal metamaterials.

The process of diffusion is central to the ever increasing entropic state of the universe and is fundamental in many branches of science and engineering. Although non-reciprocal metamaterials are well developed for wave systems, the studies of diffusive metamaterials have been limited by their characteristic spatial inversion symmetry and time inversion antisymmetry. Here, we achieve large spatial asymmetric diffusion characteristics inside a metamaterial whose material parameters are space- and time-modulated. Inside such a spatiotemporal metamaterial, diffusion occurs as if the material had an intrinsic flow velocity, whose direction is dictated by the relative phase between the modulations of the conductivity and capacity. This creates dramatic out-of-equilibrium concentrations and depletions, which we demonstrate experimentally for the diffusion of electric charges in a one-dimensional electrical system composed of an array of space-time-modulated variable capacitors and switches. These results may offer exciting possibilities in various fields, including electronics, thermal management, chemical mixing, etc.

Morphological characteristics and seed viability of Schizolobium parahyba (Vell.) S.F. Blake / Características morfológicas y viabilidad de semillas de Schizolobium parahyba (Vell.) S.F. Blake

ABSTRACT Schizolobium parahyba is a fast-growing tropical tree, with various uses: forestry, agroforestry, landscaping, boat building, cabinetmaking and light packaging. Studies of morphometry and viability of forest species seeds are important for their identification, conservation and sustainable use. The objective of the study was to describe the morphometric and viability characteristics of the seeds of S. parahyba. Seeds of free pollination of plantations from three locations in Tierralta (Córdoba - Colombia) were used. In each plantation, five trees were randomly taken and, of each, 100 seeds to estimate the morphometric characteristics and seed weight. The morphological description was made with a sample of 10 seeds. The viability was determined by the tetrazolium test in an experiment under a completely randomized design, with six treatments and four replicates of 25 seeds each. The six treatments corresponded to the combinations of three concentrations of tetrazolium (0.5; 1.0 and 1.5%) and two staining times (2 and 3 hours). The width, length, and ratio width / length of the seed showed little variation, compared to the freshweight of a seed, freshweight of 100 seeds and number of seeds per kilogram. Tetrazolium and germination tests showed similar and reliable results. The concentration of 0.5% tetrazolium, with immersion of 2 hours, was sufficient to determine the viability of seeds of S. parahyba.

RESUMEN Schizolobium parahyba es un árbol tropical de crecimiento rápido, con diversos usos: forestería, agroforestería, paisajismo, construcción de embarcaciones, ebanistería y embalajes livianos. Los estudios de morfometría y viabilidad de semillas de especies forestales son importantes para la identificación, la conservación y el uso sostenible de éstas. El objetivo del estudio fue describir las características morfométricas y viabilidad de la semilla de S. parahyba. Se utilizó semilla sexual de polinizaciónlibre de plantaciones de tres localidades de Tierralta (Córdoba, Colombia). En cada plantación, se tomaron al azar cinco árboles y de cada uno 100 semillas, para la estimación de las características morfométricas y el peso de la semilla. La descripción morfológica, se hizo con una muestra de 10 semillas. La viabilidad, se determinó mediante la prueba de tetrazolio, en un experimento bajo un diseño completamente al azar, con seis tratamientos y cuatro repeticiones de 25 semillas cada una; los seis tratamientos correspondieron a las combinaciones de tres concentraciones de tetrazolio (0,5; 1,0 y 1,5%) y dos tiempos de tinción (2 y 3 horas). Las características de ancho, longitud y relación ancho/longitud de la semilla, acusaron poca variación, en comparación con el peso de una semilla, peso frescode 100 semillas y número de semilla por kilogramo. Las pruebas de tetrazolio y de germinaciónmostraron resultados similares y confiables. La concentración de 0,5% de tetrazolio, con inmersión de 2 horas, es suficiente para determinar la viabilidad de la semilla de S. parahyba.

Utilidad de los modelos predictivos de embolia pulmonar / Usefulness of predictive models of pulmonary embolism

ANTECEDENTES: Ante la sospecha de embolia pulmonar (EP), las guías recomiendan el empleo de escalas de probabilidad clínica, medición del dímero D y, en determinados casos, confirmar mediante angiografía pulmonar mediante tomografía computarizada (APTC) o gammagrafía. Recientemente se ha planteado ajustar el dímero D según edad o usar escalas más sencillas (algoritmo YEARS) para una mejor selección de los pacientes. OBJETIVO: Definir el grado de aplicación de las guías en nuestra población y comparar sensibilidad, especificidad y valores predictivos positivo y negativo de los diferentes modelos diagnósticos: modelo estándar (Wells 2 categorías+dímero D), modelo ajustado por edad (Wells 2 categorías+dímero D ajustado por edad), algoritmo YEARS. MATERIAL Y MÉTODOS: Estudio retrospectivo de todos los pacientes que se sometieron en nuestro centro a APTC para diagnóstico de EP durante un año. RESULTADOS: De 618 casos (el 85,4% de las APTC) iniciales se incluyeron 544 pacientes. Se diagnosticaron 113 EP (20,8%). El grado de aplicación del modelo estándar fue muy alto (90,1%) y demostró presentar la mejor relación sensibilidad y valor predictivo negativo (sensibilidad=1, valor predictivo negativo=1). Los nuevos modelos podrían reducir el número de exploraciones (17; 3,2% modelo ajustado por edad y 48; 8,8% modelo YEARS) con riesgo de falsos negativos (2 EP [1,8%] no diagnosticadas respectivamente). CONCLUSIONES: Los modelos diagnósticos actuales para EP llevan a la realización de un gran número de exploraciones innecesarias. Los nuevos modelos podrían reducir el número de APTC aunque con un mínimo riesgo de falsos negativos

BACKGROUND: Faced with the suspicion of pulmonary embolism (PE), the guidelines recommend the use of clinical probability scales, measurement of D-dimer and, in certain cases, confirmation by pulmonary angiography by computed tomography (CTPA) or scintigraphy. Recently, it has been proposed to adjust the D-dimer according to age or use simpler scales (YEARS algorithm) for a better selection of patients. OBJECTIVE: To define the degree of application of the guidelines in our population and compare sensitivity, specificity and positive and negative predictive values of the different diagnostic models: Standard model (Wells 2 categories+D-dimer), Model adjusted for age (Wells 2 categories+D-dimer adjusted for age), YEARS algorithm. MATERIAL AND METHODS: A retrospective study of all patients who underwent APTC at our centre for the diagnosis of PE over one year. RESULTS: Of 618 cases (85.4% of initial APTC), 544 patients were included. A total of 113 EPs were diagnosed (20.8%). The degree of application of the standard model was very high (90.1%) and proved to have the best sensitivity and negative predictive value ratio (sensitivity=1.0, negative predictive value=1.0). The new models could reduce the number of scans (17, 3.2% model adjusted for age and 48, 8.8% model YEARS) with a risk of false negatives (2 PE [1.8%] undiagnosed respectively). CONCLUSIONS: The current diagnostic models for PE lead to a large number of unnecessary explorations. The new models could reduce the number of APTC although with a minimum risk of false negatives