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Introduction: One of the main bottlenecks in restoration projects based on sexual reproduction is post-settlement survival, mainly due to competition for substrate with fleshy algae and predation. Therefore, substrates of different shapes and materials have been created and tested, seeking to optimize these processes with attractive surfaces for the larvae and structures where the recruits are protected from predation, and competition is reduced. Objective: To improve settlement and post-settlement survival of two important Caribbean reef-building corals, using different coatings on substrates. Methods: To determine whether substrate coatings properties are favourable to larval settlement in Orbicella annularis, and O. faveolata, collected in Puerto Morelos, Mexican Caribbean, we evaluated their settlement for three weeks on six coatings with a combination of properties. Each coating was designed to provide a combination of two out of three properties: 1) water repellence (hydrophobicity), 2) phosphorescence-based colour, and 3) mineral-enriched surface chemistry. In a separate experiment larvae settlement was tested using coatings with a single property. Finally, we determined the post-settlement survival of O. annularis and O. faveolata on the different coatings for seven weeks. Results: The combination of high hydrophobicity and light blue phosphorescent microparticles and high hydrophobicity and red-orange phosphorescent microparticles resulted in a higher settlement of O. annularis and O. faveolata when compared with other coatings (30.8 - 66.7 % higher). No significant differences were found in the number of larval settled when the water-repellence and the phosphorescence-based were evaluated independently. Post-settlement survival time on substrates was low, with a maximum of 34 days after settlement for O. annularis and 42 days for O. faveolata. Conclusions: In terms of the larval settlement, the combination of the coatings properties appears to play an essential role in the choice of microhabitat for both O. annularis and O. faveolata. But individually these properties did not generate an advantage in the larval settlement. Moreover, some chemical components associated with the coatings may be counterproductive to the survival of the polyps over time.

La comúnmente llamada Fusariosis de las musáceas es un patógeno que representa una amenaza para la seguridad alimentaria global. Es responsable de pérdidas considerables en la producción de plátano y banano en el mundo. Por casi 30 años, su presencia se restringió al Sureste asiático, sin embargo, en agosto de 2019 se detectó por vez primera en Colombia y se consideró un nuevo riesgo fitosanitario en América. Se modelaron los patrones espaciales de Fusarium oxysporum, f. sp. cubense raza 4 tropical (FocR4T) a nivel global y subcontinental (América pantropical) bajo un enfoque que integró los componentes epidémico y espacial, e incluyó la distribución potencial (patógeno/hospedante) y el potencial de daño económico por asociación espacial de nodos comerciales (origen/destino), lo cual se integró mediante la evaluación multicriterio (MCDA). A nivel territorial se caracterizaron cinco niveles de riesgo fitosanitario (muy alto, alto, medio, bajo y muy bajo). A escala global se determinó la existencia de cuatro áreas focales donde existen condiciones para la ocurrencia de la enfermedad. En la América pantropical se determinó la existencia de 26 598 km2 en riesgo fitosanitario muy alto (>0.9) ubicado por mayor extensión en Ecuador, Brasil, México, Guyana, Guatemala, Venezuela, Panamá y Colombia, aunque también existen 15.8 millones de km2 con un nivel de riesgo inferior. La cartografía obtenida representa una herramienta valiosa para fortalecer y direccionar las acciones preventivas en la dispersión de este patógeno en la región y se considera un insumo técnico/científico que fortalece el análisis de riesgo de plagas realizado por las organizaciones regionales y nacionales de protección fitosanitaria.

The human hand is a manipulator with extraordinary capabilities, the elements that constitute it make its emulation too complex. There are manipulators with amazing and outstanding abilities that have become too complex and costly. Alternatively, there are under-actuated and self-adaptive manipulators that are simple and affordable, have appropriate performance, although their functions and gripping modes are limited and may not be entirely reliable. This paper exposes the proposal of a 12-gear reducer mechanism in 3 phases with linear array, designed to maintain a constant link transmission, amplifying the torque while the angular speed is reduced exponentially. The mechanism is attached a finger casing based on anthropomorphic aspects and is replicated twice, turning the finger into a fully actuated mechanism and with the possibility of being adaptive to different grip modes. A broad description of the system elements and their design rationale is presented. A mathematical model is developed to know the performance of the finger as a function of torque, force, angular speed and execution time of the movement, the results obtained are shown graphically accompanied by their respective concept expressions. Subsequently, the conclusions are presented. Finally, future works are described.

[ES] Recientemente se aprobó en Colombia, la Ley 2081/21 “Por la cual se declara la imprescriptibilidad de la acción penal en caso de delitos contra la libertad, integridad y formación sexuales, o el delito de incesto, cometidos en menores de 18 años – no más silencio”, cuyo principal objetivo sería alentar a las víctimas para que denuncien la ocurrencia de tales delitos, sin límite temporal, y de esta manera contener su comisión en aras de realizar una efectiva protección a los menores de edad del país. Así, en esta investigación se presenta un análisis crítico acerca de la pertinencia o no de esta medida, en un sistema penal como el colombiano, a partir de la revisión de instituciones jurídicas como la prescripción e imprescriptibilidad de la acción penal, atendiendo su origen, fundamentos, y efectos prácticos., [EN Recently, Law 2081/21 was approved in Colombia “By which the non-prescription of criminal action is de-clared in lawsuits of crimes against sexual freedom, integrity, and exercise, or the crime of incest, committed in minors under 18 years - no more silence”, whose main objective would be to encourage victims to report the occurrence of such crimes, without a time limit, and thus contain their commission to effectively protect minors in the country. Thus, in this research, a critical analysis is presented about the relevance or not of this measure, in a penal system such as the Colombian one, based on the review of legal institutions such as the prescription and non-prescription of criminal action, attending to its origin, foundations, and practical effects.]

La Administración de la Cadena de Suministros y la inclusión de la tecnología como unaherramienta para su eficiencia, lo que hoy se denomina Cadenas de Suministro Inteligentes.Este tema es de alta importancia para las empresas en la actualidad, por esta razón el presenteartículo hace una revisión de este bajo dos escenarios, el primero basado en el procesoutilizado por las empresas de manufactura en Costa Rica para su Cadena de Suministros y elsegundo fue orientado a entender la implementación de un enfoque inteligente de acuerdo conel criterio de expertos austriacos. Tomando como base la información recolectada, el estudiodiseña un modelo para la gestión de cadenas de suministro inteligentes con las característicasmás relevantes para cada escenario. Finalmente, el análisis permitió concluir que actualmentela información en tiempo real es esencial para la Administración de la Cadena de Suministros.

Supply Chain Management and the technology adoption as a tool to increase efficiency is alsoknown as Smart Supply Chain. This topic has become of importance in companies nowadays.Thus, this research analyzes this topic within two scenarios. The first one based on the processused by manufacturing companies in Costa Rica to their Supply Chain and the second wasoriented to understand the implementation of a smart approach according to Austrian expertcriteria. Based on the collected information a model for each scenario was designed with themost relevant characteristics. Finally, the analysis allowed to conclude that currently real-timeinformation is essential for Supply Chain Management. La Administración de la Cadena de Suministros y la inclusión de la tecnología como unaherramienta para su eficiencia, lo que hoy se denomina Cadenas de Suministro Inteligentes.Este tema es de alta importancia para las empresas en la actualidad, por esta razón el presenteartículo hace una revisión de este bajo dos escenarios, el primero basado en el procesoutilizado por las empresas de manufactura en Costa Rica para su Cadena de Suministros y elsegundo fue orientado a entender la implementación de un enfoque inteligente de acuerdo conel criterio de expertos austriacos. Tomando como base la información recolectada, el estudiodiseña un modelo para la gestión de cadenas de suministro inteligentes con las característicasmás relevantes para cada escenario. Finalmente, el análisis permitió concluir que actualmentela información en tiempo real es esencial para la Administración de la Cadena de Suministros.

This paper presents the analysis and computer simulation of the rotational and transverse oscillations present in a circular motion transmission system through the relationship of pulley-ribbed belt, widely used in the industrial robots. The analysed system is a pulley-ribbed belt coupled with rigid pulleys. The analysis is based in the mathematical model developed for serpentine belt drive systems. The analysis includes: (i) the geometric characteristics, (ii) the behavior of the transmission in steady state, and (iii) the dynamical response of the system. Dynamic analysis of these type of systems is complex because: (i) it has coupled rotational and transverse vibration modes in a non-linear form, and (ii) includes a circular motion transmission system acceleration-deceleration profile. The proposed analysis allows to determine a priori the frequency, the phase shift and the oscillation amplitude of a section of the ribbed belt excited by any forced velocity profile.

Los áfidos representan plagas que atacan a un sinnúmero de cultivos y son capaces de hospedarse sobre malezas, siendo también éstas un excelente hospedero. Su importancia radica en ser uno de los principales vectores de virus y pocos le dan importancia a estudiar su taxonomía. En el estado de Coahuila se carece de información acerca de la diversidad existente de áfidos, a pesar de la importancia que éstos representan en los cultivos agrícolas del estado. En el presente estudio se realizaron colectas semanales de manera directa durante un año a partir de agosto 2009 a agosto 2010, en el sureste de Coahuila sobre malezas y cultivos presentes en la región. Se colectó el material tanto de las partes aéreas, tallos, raíz, flores dependiendo del lugar de ubicación. El material se procesó en el laboratorio de taxonomía de la UAAAN para su posterior análisis taxonómico. Fueron determinados 21 géneros y 27 especies, la especie dominante fue Macrosiphium euphorbiae en un amplio número de hospedantes de cultivos y malezas, seguida por Aphis spiraecola; ambas de importancia agrícola al transmitir virus a los cultivos. Dichas especies fueron recolectadas 22 especies de plantas hospederas. La familia Asteraceae representó el principal anfitrión, de un total de 27 especies de áfidos, 11 fueron recolectadas en hospederas de esta familia. Siguiendo en orden de importancia las familias Poaceae, Apiaceae, Cruciferae, Roseaceae, Polygonaceae, Solanaceae, siendo éstas las más representativas.

La información política y económica no suele ser de gran relevancia para el sector más joven de la sociedad. El desconocimiento de cómo se estructuran los grandes conglomerados o cuáles son las conexiones que hay entre el poder político y económico y los medios de comunicación supone un riesgo para sociedad. ¿Lo que nos ofrecen realmente es información libre y objetiva? ¿Cómo sabemos si lo que nos dicen los medios no está influenciado por estos poderes? El objetivo de este proyecto es concienciar a los jóvenes sobre las conexiones que hay entre estos actores y la posible influencia que ejercen en la sociedad. La herramienta idónea para ello es el docugames, utilizar las técnicas de los juegos en contextos no lúdicos para ofrecer la información de una forma más atractiva para este sector. Universidad de Sevilla. Grado en Periodismo

Resumen Introducción: Las técnicas continuas de depuración extrarrenal son la terapia de elección en pacientes críticos. Pero, no están exentas de complicaciones como la coagulación del circuito extracorpóreo. El fármaco usado tradicionalmente para la anticoagulación, es la heparina sódica. Aunque también son empleados otros métodos de anticoagulación, como el citrato. Objetivo: Evaluar la eficacia y seguridad de dos métodos de anticoagulación en pacientes tratados con terapias continuas, en unidades de cuidados intensivos del Hospital Clínic. Material y Método: Estudio observacional, retrospectivo de 54 sujetos. Se aplicaron los criterios de Insuficiencia renal aguda, descritos en el protocolo "Guía para el tratamiento sustitutivo renal en la insuficiencia renal aguda del Hospital Clínic". Tratados mediante hemodiafiltración, combinando terapias de convección y difusión. Con fracción de filtración < 25%, y dosis de efluente de 30 ml/kg/h. 27 sujetos realizaron hemodiafiltración, reposición pre-filtro y anticoagulación con heparina sódica. El resto, hemodiafiltración, reposición post-filtro y anticoagulación con citrato. Se valoraron episodios de sangrado y duración en horas de los circuitos extracorpóreos, durante 72 horas de terapia. Resultados: El citrato demostró una mayor supervivencia de filtros (95% IC, MD 65, 44.00-72.00 vs MD 36.00, 15.00-22.00, p=0,02). Los pacientes tratados con heparina presentaron más episodios de sangrado, sin diferencias estadísticamente significativas (95% IC, n=6 vs n=9, p=0.537). Hubo un episodio de hipocalcemia en el grupo citrato, corregido según protocolo. En el grupo heparina, no se presentaron casos de trombocitopenia inducida por heparina. Conclusiones: El presente estudio, demuestra una mayor eficacia en la supervivencia de los filtros en el grupo citrato. Abstract Introduction: Continuous extra-renal depuration techniques are the therapy of choice in critically ill patients. But, they are not exempt from complications such as the coagulation of the extracorporeal circuit. The drug traditionally used for anticoagulation is sodium heparin. Although other methods of anticoagulation, such as citrate, are also used. Objective: To evaluate the efficacy and safety of two anticoagulation methods in patients treated with continuous therapies, in intensive care units of the Hospital Clinic of Barcelona. Material and Method: A retrospective observational study with 54 subjects was carried out. The criteria of acute renal insufficiency, described in the protocol "Guide for renal replacement therapy in acute renal failure at the Hospital Clínic" were applied. Patients were treated by hemodiafiltration, combining convection and diffusion therapies; with filtration fraction < 25%, and effluent dose of 30ml/kg/h. Twenty-seven subjects performed hemodiafiltration, pre-filter replacement and anticoagulation with sodium heparin. The rest, hemodiafiltration, post-filter replacement and anticoagulation with citrate. Episodes of bleeding and duration in hours of the extracorporeal circuits were evaluated during 72 hours of therapy. Results: Citrate demonstrated a greater survival of filters (95% CI, MD 65, 44.00-72.00 vs. MD 36.00, 15.00-22.00, p=0.02). Patients treated with heparin had more episodes of bleeding, without statistically significant differences (95% CI, n=6 vs. n=9, p=0.537). There was an episode of hypocalcemia in the citrate group, corrected according to protocol. In the heparin group, there were no cases of heparin-induced thrombocytopenia. Conclusions: The present study demonstrates greater efficacy in the survival of filters in the citrate group.

Pinus pseudotrobus es una especie con aprovechamiento maderable, distribuida en un amplio gradiente altitudinal, de 1.600 a 3.250 m, lo que sugiere una varianza genética que puede ser aprovechada mediante la selección de árboles que provean semillas que generen plantas con altas tasas de crecimiento relativo. Por lo anterior, se evaluó la sobrevivencia y crecimiento inicial de Pinus pseudostrobus en vivero, con base en la variación de progenies de 38 árboles sobresalientes (procedencias) en rodales naturales de la Sierra Norte de Oaxaca, México. La siembra se realizó en febrero de 2013 en un vivero localizado en Ixtlán de Juárez, cercano a la región de colecta, a 2030 msnm y un clima templado. Además de evaluar la sobrevivencia de 54 a 166 días después de la siembra (dds), se estimaron cinco lecturas de altura de planta, diámetro basal de tallo y cuatro lecturas de número de braquiblastos, y se calculó la tasa de crecimiento relativo para altura de planta. Mediante un análisis de varianza y comparación de medias se determinaron diferencias significativas entre procedencias, en todas las variables. En la evaluación se manifestó un crecimiento exponencial de plantas en vivero, con un promedio de 0,8 a 1,5 mm de altura/día de 54 a 166 dds y un promedio de 1 a 2 braquiblastos en ramillas primarias y secundarias por día en un intervalo de 82 a 166 dds. Del total de procedencias, cuatro de ellas mostraron una alta tasa de crecimiento. Pinus pseudostrobus is a species with timber harvesting, distributed over a wide altitudinal gradient of 1,600-3,250 m, suggesting a genetic variance, which can be exploited by selecting trees that provide seeds in order to produce plants with high relative growth rates. Therefore, survival and early growth of Pinus pseudostrobus were evaluated under nursery conditions, based on the variation in offsprings of 38 outstanding trees (provenances) in natural stands from Sierra Norte of Oaxaca, Mexico. Seeds were sowing in February 2013 at a nursery located in Ixtlan de Juarez, near the collection site, to 2030 masl and a temperate climate. Survival from 54-166 days after planting (dap) was evaluated, five readings of plant height, basal stem diameter, four readings of number of brachyblasts were recorded, and the relative growth rate for plant height was estimated. Using analysis of variance and mean tests, significant differences among provenances were determined in all variables. In the evaluation, the plants in the nursery showed an exponential growth, an average of 0,8 to 1,5 mm in height/day of 54-166 dap and an average of 1-2 brachyblasts on primary and secondary branches per day in a range of 82-166 dap. From total provenances, four showed high growing rate.

Based on the hypothesis that reproduction is a continuous process in tropical habitats, we analysed reproductive periodicity and egg production in the callianassid ghost shrimp Lepidophthalmus bocourti, one of the most common species in mangrove systems along the Pacific coast of Central America. During one year (May 2008 to April 2009), individuals of L. bocourti (N=499) were collected nearshore Gulf of Nicoya, Pacific coast of Costa Rica. Observations were made on presence or absence of incubated embryos, and gonad activity of females was analysed as gonadosomatic index (GSI). Our results revealed that L. bocourti has a marked seasonal breeding period, which contradicts previous reports regarding coastal marine decapods from the tropics. Ovigerous females were found only from June to August, while high GSI values were obtained from March to July. The increase of GSI and appearance of ovigerous females were associated with a concomitant decrease of salinity, but not with temperature. We assume t...

The application of a powerful evolutionary optimization technique for the estimation of intrinsic formation constants describing geologically relevant adsorption reactions at mineral surfaces is introduced. We illustrate the optimization power of a simple Genetic Algorithm (GA) for forward (aqueous chemical speciation calculations) and inverse (calibration of Surface Complexation Models, SCMs) modeling problems of varying degrees of complexity, including problems where conventional deterministic derivative-based root-finding techniques such as Newton–Raphson, implemented in popular programs such as FITEQL, fail to converge or yield poor data fits upon convergence. Subject to sound a priori physical–chemical constraints, adequate solution encoding schemes, and simple GA operators, the GA conducts an exhaustive probabilistic search in a broad solution space and finds a suitable solution regardless of the input values and without requiring sophisticated GA implementations (e.g., advanced GA operators, parallel genetic programming). The drawback of the GA approach is the large number of iterations that must be performed to obtain a satisfactory solution. Nevertheless, for computationally demanding problems, the efficiency of the optimization can be greatly improved by combining heuristic GA optimization with the Newton–Raphson approach to exploit the power of deterministic techniques after the evolutionary-driven set of potential solutions has reached a suitable level of numerical viability. Despite the computational requirements of the GA, its robustness, flexibility, and simplicity make it a very powerful, alternative tool for the calibration of SCMs, a critical step in the generation of a reliable thermodynamic database describing adsorption equilibria. The latter is fundamental to the forward modeling of the adsorption behavior of minerals and geologically based adsorbents in hydro-geological settings (e.g., aquifers, pore waters, water basins) and/or in engineered reactors (e.g., mining, hazardous waste disposal industries).

Despite the success of surface complexation models (SCMs) to interpret the adsorptive properties of mineral surfaces, their construct is sometimes incompatible with fundamental chemical and/or physical constraints, and thus, casts doubts on the physical–chemical significance of the derived model parameters. In this paper, we address the definition of primary surface sites (i.e., adsorption units) at hydrated carbonate mineral surfaces and discuss its implications to the formulation and calibration of surface equilibria for these minerals. Given the abundance of experimental and theoretical information on the structural properties of the hydrated (10.4) cleavage calcite surface, this mineral was chosen for a detailed theoretical analysis of critical issues relevant to the definition of primary surface sites. Accordingly, a single, generic charge–neutral surface site („CaCO3� H2O 0 ) is defined for this mineral whereupon mass-action expressions describing adsorption equilibria were formulated. The one-site scheme, analogous to previously postulated descriptions of metal oxide surfaces, allows for a simple, yet realistic, molecular representation of surface reactions and provides a generalized reference state suitable for the calculation of sorption equilibria for rhombohedral carbonate minerals via Law of Mass Action (LMA) and Gibbs Energy Minimization (GEM) approaches. The one-site scheme is extended to other rhombohedral carbonate minerals and tested against published experimental data for magnesite and dolomite in aqueous solutions. A simplified SCM based on this scheme can successfully reproduce surface charge, reasonably simulate the electrokinetic behavior of these minerals, and predict surface speciation agreeing with available spectroscopic data. According to this model, a truly amphoteric behavior is displayed by these surfaces across the pH scale but at circum-neutral pH (5.8–8.2) and relatively high RCO2 (P1 mM), proton/bicarbonate co-adsorption becomes important and leads to the formation of a charge–neutral H2CO3-like surface species which may largely account for the surface charge-buffering behavior and the relatively wide range of pH values of isoelectric points (pHiep) reported in the literature for these minerals.

Roothaan-Hartree-Fock molecular orbital methods were applied to investigate the ground-state structural, energetic properties, and bonding relationships of the hydrated (10.4) calcite surface. The adsorption of water molecules was modeled at the 6-31G(d,p) level of theory using Ca(n)(CO(3))(n) slab cluster models (4or= nor= 18) with a varying number of H(2)O monomers (2or= (H(2)O)(n)or= 6) interacting with the surface. Modeling results add fresh insights into the detailed 3D structural registry of the first and second hydration layers and the reconstructed (10.4) calcite surface, complementary to the information acquired from earlier atomistic, density functional, X-ray scattering, and grazing incidence X-ray diffraction studies. Both the modeled energies and geometries agree best with results of earlier density functional calculations, supporting the associative character of adsorbed water molecules. Two adsorption configurations are postulated: (i) H(2)O molecules interacting with surface Ca through ionic bonding and by hydrogen bonding to a surface O with their dipole slightly oblique above the surface (1st hydration layer), and (ii) H(2)O molecules that hydrogen bond to surface O and to H(2)O molecules in the first hydration layer with their dipole nearly parallel to the surface (2nd hydration layer). These interactions are consistent with the "chemisorption" and "physisorption" of H(2)O on calcite surfaces, proposed on the basis of previous thermogravimetric and Fourier-transformed infrared studies. Most significant is the distortion of the surface Ca-O octahedra caused by the relaxation (and possibly rupture) of some Ca-O bonds upon hydration, weakening the topmost atomic layer. These findings are consistent with interpretations of X-ray photoelectron spectroscopy, density functional theory, and electrokinetic studies that suggest the preferential release of surface Ca atoms over surface CO(3) groups upon hydration of the cleavage surface. These insights will help to elucidate mechanisms of carbonate mineral dissolution, the rearrangement of surface layers, ion replacement, charge development, and solute transport through subsurface lattice layers.

This project deals about the solution of the Navier Stokes Equations by the Method of Characteristics -- This method is used to eliminate the convective part of equations of the convection-diffusion type, conducting the material derivative in a Lagrangian manner along the characteristic curves of each node in a fixed grid -- Following this approach, the method is able to solve the incompressible Navier Stokes Equations with the advantage of using large timesteps -- In the present case, the solution of the well known Lid Driven Cavity Flow problem is obtained for several Reynolds numbers, showing good agreement when compared to solutions obtained by other methods

Tesis doctoral inédita leída en la Universidad Complutense de Madrid. Fecha de lectura: 17-9-2013.