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La presencia de Nivel Freático (NF) subsuperficial en áreas agrícolas afecta el desarrollo de los cultivos y provoca la salinización del suelo, estos problemas asociados a niveles freáticos someros se han controlado mediante la instalación de sistemas de drenaje subterráneo. Una forma de estudiar este fenómeno es a través de la evaluación experimental de modelos matemáticos, con la cual se pueden controlar las variables de entradas y salidas. En este trabajo se midió la variación del NF provocado por dos drenes paralelos instalados en un perfil de suelo saturado y se comparó con la modelación dinámica de agua utilizando Hydrus-2D® que resuelve numéricamente la ecuación de Richards. El modelo físico experimental tenía dimensiones de 2.44x1.22x122 m y contenía un perfil de suelo de 0.9 m de espesor compuesto por un estrato franco y otro franco arcilloso, con conductividades hidráulicas saturadas (Ks) de 24.96 y 6.24 cm/día, respectivamente. En el centro del contenedor del modelo experimental se instalaron nueve Pozos de Observación (PO) de 3 cm de diámetro, conectados a piezómetros externos para medir la profundidad del NF durante 17 h. Los resultados mostraron que el modelo Hydrus-2D se ajusta mejor en tiempos mayores a 10 h debido a que el RMSE varió de 14.96 a 1.03 cm, en el caso de la EF cambió de -52.45 a -0.43, por lo tanto, se considera que Hydrus-2D puede ser una herramienta útil para el diseño de drenajes subterráneos parcelarios.

Due to global change, many species are shifting their distribution and are thereby confronted with novel thermal conditions at the moving range edges. Especially during the initial phases of exposure to a new environment, it has been hypothesized that plasticity and associated epigenetic mechanisms enable species to cope with environmental change. We tested this idea by capitalizing on the well-documented southward range expansion of the damselfly Ischnura elegans from France into Spain where the species invaded warmer regions in the 1950s in eastern Spain (old edge region) and in the 2010s in central Spain (new edge region). Using a common garden experiment at rearing temperatures matching the ancestral and invaded thermal regimes, we tested for evolutionary changes in (thermal plasticity in) larval life history and heat tolerance in these expansion zones. Through the use of de- and hypermethylating agents, we tested whether epigenetic mechanisms play a role in enabling heat tolerance during expansion. We used the phenotype of the native sister species in Spain, I. graellsii, as proxy for the locally adapted phenotype. New edge populations converged toward the phenotype of the native species through plastic thermal responses in life history and heat tolerance while old edge populations (partly) constitutively evolved a faster life history and higher heat tolerance than the core populations, thereby matching the native species. Only the heat tolerance of new edge populations increased significantly when exposed to the hypermethylating agent. This suggests that the DNA methylation machinery is more amenable to perturbation at the new edge and shows it is able to play a role in achieving a higher heat tolerance. Our results show that both (evolved) plasticity as well as associated epigenetic mechanisms are initially important when facing new thermal regimes but that their importance diminishes with time.

This paper introduces a new decentralized control strategy for an unmanned aerial manipulator (UAM) constrained to the vertical plane. The control strategy comprises two loops: the first compensates for the aerial vehicle’s impact on the manipulator; and the second one implements independent controllers for the aerial vehicle and the manipulator. The controller for the aerial vehicle includes an estimator to compensate for the dynamic influence of the manipulator, even if it is affected by external wind-gust disturbances. The manipulator has two revolute joints; however, it is modeled as an dynamically equivalent manipulator, with one revolute and one prismatic joint. The proposed control strategy’s performance is evaluated using a simulator that includes the vehicle’s aerodynamics and the manipulator’s contact force and moment.

The posttranslational modification of proteins critically influences many biological processes and is a key mechanism that regulates the function of the RNA-binding protein Hu antigen R (HuR), a hub in liver cancer. Here, we show that HuR is SUMOylated in the tumor sections of patients with hepatocellular carcinoma in contrast to the surrounding tissue, as well as in human cell line and mouse models of the disease. SUMOylation of HuR promotes major cancer hallmarks, namely proliferation and invasion, whereas the absence of HuR SUMOylation results in a senescent phenotype with dysfunctional mitochondria and endoplasmic reticulum. Mechanistically, SUMOylation induces a structural rearrangement of the RNA recognition motifs that modulates HuR binding affinity to its target RNAs, further modifying the transcriptomic profile toward hepatic tumor progression. Overall, SUMOylation constitutes a mechanism of HuR regulation that could be potentially exploited as a therapeutic strategy for liver cancer.

The design of a novel strategy based on the model reference adaptive control method for the stabilisation of a second-order linear time-delay system with unknown parameters is presented. The proposed approach is developed under the assumption that only one state of the system is available, and the sign of the control gain is known. First, the integral operator is applied to obtain a new representation of the original system, where the whole state is known. The use of the integral operator decomposes the control problem into two subproblems that are solved by using the model reference adaptive control method and the backstepping procedure. The effectiveness of the proposed approach is illustrated through an academic example and a practical application case regarding a chemical reactor recycle system.

In the quest for advancing the performance of metallic implants, surface modification emerges as a pivotal strategy to mitigate ion depletion, enhance the host's biological response, and exhibit anti-microbial behavior with reduced cytotoxicity. In this study, we developed a non-traditional electrophoretic deposition (EPD) hybrid coating for medical-grade stainless steel 316 L (SS316L) surfaces covered with a segmented polyurethane (SPU). These coatings are composed of anatase TiO₂ nanotubes (TiO₂_A), and antibiotics (nisin N or gentamicin G). We characterized the modified metals using FTIR and Raman spectroscopy, contact angle measurements, AFM, TGA, SEM-EDX, as well as assessing their antimicrobial response and cell cytotoxicity. The results demonstrate the formation of porous surfaces with embedded nanotubes and antibiotics within and on the polyurethane surfaces. Samples with SPU+ TiO₂_AG EPD exhibited superior coverage, antimicrobial properties, and enhanced viability compared to cases where only particles or antibiotics were coated individually. Additionally, samples of SPU+ TiO₂_AN EPD displayed favorable hydrophilicity and suitable cytotoxicity. Therefore, the synergistic effect of nanoparticles and antibiotics positively influences the functionality of the coating.

Specimens of Poecilosclerida taxa, collected from an insular coral community on the Pacific coast of Mexico, were identified as members of the family Crambeidae Lévi, 1963. They were associated with larvae and rhagon phases by using morphological characters, the nucleotide relationship and genetic divergence of three independent loci, two mitochondrial (COI and 16S rDNA) and one ribosomal (28S rDNA C3–C5). Crambe insularis sp. nov. differs from the general skeletal architecture in the genus Crambe Vosmaer, 1880, by its reduced spiculation defined by the presence of ectosomal and choanosomal monactinal megascleres, and the absence of microscleres. Bayesian and Maximum–Likelihood analyses of three loci supported the clustering of larvae, rhagon and adult sponge, all closely related to Mediterranean Crambe crambe (type species of the genus Crambe), and with South American Crambe species (C. chilensis, C. maldonadoi and C. amarilla) as sister species. The larva of C. insularis sp. nov. corresponded to the typical parenchymella larvae poecilosclerid species but with the presence of subtylostyles and styles. Ontogenetic process about the larval and rhagon of this new crambeid are provided. The morphological characters and molecular affinities of Crambe insularis sp. nov. are similar to Monanchora genus, and the implications are further discussed. This is the first taxonomic and molecular study with an integrative approach that includes other diagnostic features such as larval and rhagon development for the description of new species in Porifera.

Desmodesmus sp. microalgae previously employed in wastewater management was reused as a raw material for producing green nanofibrous membranes through electrospinning. The reduction of biowastes as well as the replacement of common non-degradable plastics would benefit the process sustainability. In this work, different amounts of microalgae (1.25%, 2.5% and 5% wt) were dispersed in an acetic acid/water solution (80/20) and then electrospun at 0.3 mL/h, 25 kV. The presence of acetate cellulose (17%) was required to obtain nanofibres since the microalgae solutions were not sufficiently viscous for electrospinning processing. For the first time, the effect of ultrasound (50 and 125 kWh/kg), and ozone (9 mg/kg) on microalgae before the electrospinning process was evaluated. Ultrasound prompted cell rupture, which allowed both a greater release and higher exposure of the protein, which eventually enabled the formation of nanofibers from the microalgae waste. However, when the intensity of ultrasounds increased from 50 to 125 kWh/kg, a higher presence of aggregates and defects in the fibres could be observed, probably due to protein aggregation. Thus, nanofibrous mats with c.a. 50 nm fibre diameter were obtained when ultrasound pre-treatment at 50 kWh/kg was applied. Protein unfolding was also inferred from the rheological measurements, as higher viscosity values were obtained (∼ 4.1 Vs. 2.5 Pa·s for 50 and 125 kWh/kg ultrasounds, respectively). The present work highlights the potential that Desmodesmus sp. microalgae have in the production of green electrospun mats, still quite unexplored. These bio-based mats possess great potential in different applications that can range from filtering to scaffolds.

Plant-animal mutualisms such as seed dispersal are key interactions for sustaining plant range shifts. It remains elusive whether the organization of interactions with seed dispersers is reconfigured along the expansion landscape template and, if so, whether its effects accelerate or slow colonization. Here we analyse plant-frugivore interactions in a scenario of rapid population expansion of a Mediterranean juniper. We combined network analyses with field surveys, sampling interactions between individual plants and frugivores by DNA-barcoding and phototrapping over two seasons. We assess the role of intrinsic and extrinsic intraspecific variability in shaping interactions and we estimate the individual plant contributions to the seed rain. The whole interaction network was highly structured, with a distinct set of modules including individual plants and frugivore species arranged concordantly along the expansion gradient. The modular configuration was partially shaped by individual neighbourhood context (density and fecundity) and phenotypic traits (cone size). Interaction reconfiguration resulted in a higher and more uneven propagule contribution, with most effective dispersers having a prominent role at the colonization front stand, where a distinct subset of early arriving plants dominated the seed rain. Our study offers new insights into the key role of mutualistic interactions in colonization scenarios by promoting fast plant expansion processes.

Background: Charge-exchange (CE) reactions offer a major opportunity to excite nuclear isovector modes, providing important clues about the nuclear interaction in the medium. Moreover, double charge-exchange reactions are proving to be a tempting tool to access nuclear transition matrix elements (NMEs) related to double beta-decay processes. The latter are also of crucial importance to extract neutrino properties from the half-life of the hypothetical neutrinoless double beta decay and to search for physics beyond the standard model. Purpose: Through a multichannel experimental analysis and a consistent theoretical approach of the 116 Cd ( 20 Ne , 20 F ) 116 In single charge-exchange (SCE) reaction at 306 MeV, we aim at disentangling from the experimental cross section the contribution of the competing mechanisms associated with second- or higher-order sequential transfer and/or inelastic processes. Methods: We measured excitation energy spectra and absolute cross sections for elastic + inelastic, one-proton transfer and SCE channels by using the MAGNEX large acceptance magnetic spectrometer to detect the ejectiles. For the first two channels, we also extracted the experimental cross-section angular distributions. The experimental data are compared with theoretical predictions obtained by performing two-step distorted-wave Born approximation and coupled reaction channel calculations. We employ spectroscopic amplitudes for single-particle transitions derived within a large-scale shell-model approach and different optical potentials for modeling the initial- and the final-state interactions. Results: The present study significantly mitigates the possible model dependence existing in the description of these complex reaction mechanisms thanks to the satisfactory reproduction of several channels at once. In particular, our work demonstrates that the two-step transfer mechanisms produce a non-negligible contribution to the total cross section of the 116 Cd ( 20 Ne , 20 F

Policy Coherence for Sustainable Development (PCSD) has promoted sustainability through policy coordination, but to what extent does it respond to the needs of local communities? Scholars of PCSD have acknowledged how it has been considered as an end in itself rather than a means to achieve normative impact. A major limit of PCSD has been its institutionalized nature, as mechanisms for social participation have not been highlighted in implementation strategies. This article addresses this issue. It proposes “pull-push-match” as a methodology for the es-tablishment of participative PCSD. The article, co-authored by a team of researchers and practitioners from Mexico, addresses PCSD in relation to Indigenous communities.

The study and assessment of ecosystem services through remote sensing has increased substantially over the last two decades, as evidenced by the publication of studies that have applied it. The technological development of satellite images has improved in terms of spatial, spectral, radiometric, and temporal resolution, allowing the space-time observation, classification and monitoring of vegetation on the surface of the Earth. However, there are remaining methodological challenges for assessing ecosystem services due to the diversity of applications, the resources used, and its study in complex environments such as cities. This systematic review is based on identifying and analysing the variety of methods concerning the application of remote sensing for the assessment of ecosystem services provided by vegetation in cities, through a classification of these methods according to the data collection source (passive sensors, passive and active sensors and the fusion of other data sources with sensors). The classification of methods has been applied to a selection of existing articles in indexed scientific databases based on a non-statistical meta-analysis that make a direct reference to the topic of interest. The results show the approaches found in every method classified, their relationships with the geographical scale and the image resolutions used, and the advantages and limitations from the data processes that comprise remote sensing. We conclude from this analysis with three key factors to consider in the selection of remote sensing methods for the assessment of ecosystem services provided by urban vegetation: the definition of the approach(es), the urban scale to be assessed, and the image resolution available.

A través de la recuperación de dos estudios cualitativos basados en teoría fundamentada e investigación-acción participativa, el artículo aporta elementos para la comprensión de la condición juvenil rural, cuestionando las posibilidades, tanto actuales como futuras, de las juventudes rurales para integrarse a la agricultura dominada por la agroindustriaque emergió en la zona de Ixtlahuacán del Rio y Cuquío, en Jalisco, México. Las dimensiones estructural y territorial de la condición juvenil rural permiten comprender la crisis que se cierne sobre las juventudes rurales y sobre las nuevas generaciones, a partir de la examinacióndel sistemade monocultivo de maíz y de explorar sus afectaciones socioambientales; mientras que la dimensión intersubjetiva nos da un panorama sobre la vida cotidiana de las juventudes, las relaciones intergeneracionales y sus conflictos ante tal escenario. Todo en conjunto muestra la complejidad de los espacios rurales intervenidos por la agroindustria y la amenaza que representan al futuro de las juventudes rurales y de los territorios mismos., Using two qualitative studies based on grounded theory and participatory action research, this article provides elements for understanding the rural youth condition and questioning the possibilities, both current and future, for rural youth to integrate into agriculture dominated by agribusiness that emerged in the areas of Ixtlahuacán del Rio and Cuquío in Jalisco, Mexico. The structural and territorial dimensions of the rural youth condition, based on an examination of the corn monoculture system and its socio-environmental effects, allow us to understand the crisis that looms over rural youth and the new generations. At the same time, the intersubjective dimension gives us a panoramic view of the daily life of youth and intergenerational relations, and their conflicts in the face of such a scenario. All together, this study shows the complexities of rural spaces intervened by agribusiness and the threat they represent to the future of rural youth and to the territories themselves.

Este artículo revela resultados cuantitativos y cualitativos sobre modernidad/tardomodernidad en las representaciones de raza y raza-género de personajes víctimas de violencia en 100 series de dibujos animados representativas del 33.22% de productos de TV y 54.34% de dibujos animados, consumidos por niños(as) de 7-15 años de edad en México. La metodología utilizada fue análisis de contenido y análisis correlacional de cinco categorías: Raza y Género de 1,081 personajes; y Tipos, Subtipos y Naturaleza de la violencia que estos reciben. Los resultados revelan que son personajes de raza blanca/caucásica (42.87%) y raza blanca/caucásica & género masculino (27.68%) los grupos que reciben mayor porcentaje de violencia. Se concluye que racismo tardomoderno significa que las representaciones de raza y raza-género en la muestra, producen diferenciación y jerarquización racial que inferioriza a los grupos de raza caucásica y raza caucásica – género masculino, al representar a estos grupos (de superioridad biopolítica del sujeto social en la modernidad) en mayor porcentaje como víctimas (receptores de violencia)., This article presents quantitative and qualitative results on modernity/late modernity in the representation of race and race-gender of characters that are victims of violence in 100 cartoon series representing 33.22% of TV products and 54.34% of cartoons consumed by children between 7-15 years of age in Mexico. The methodology used was content analysis and correlational analysis of five categories: race and gender of 1,081 cartoon characters; and types, subtypes and nature of the violence they receive. The results reveal that characters of white/Caucasian race (42.87%) and white/Caucasian & male gender (27.68%) are the groups that receive the highest percentage of violence. It is concluded that late modern racism means that the representations of race and race-gender in the sample produce racial differentiation and racial hierarchization. This kind of representation results in an inferior position the groups of Caucasian race and Caucasian race - male gender by representing these groups (of biopolitical superiority of the social subject in modernity) in a higher percentage as victims (recipients of violence).

Plant invasions have a huge impact on the health of ecosystems and human well-being. The invasion risk varies with the introduction pathway, the propagule pressure, and the genetic diversity of the founding population. We performed a systematic review and meta-analysis of 30 studies reporting the genetic diversity of 31 plant species in their invasive and native ranges. We evaluated if patterns of genetic diversity differ between ranges and whether these responses are influenced by life-history traits, hybridization, polyploidization, and habitat condition. We found that invasive populations had significantly lower genetic diversity and higher inbreeding than native populations. In fragmented and degraded habitats, the genetic diversity of invaders was lower, but inbreeding was not affected. Polyploid invaders with hybrid capacity also showed lower genetic diversity. Invasive herbs with vegetative propagation were more sensitive to the loss of genetic diversity and had higher levels of inbreeding. Our synthesis showed that the genetic response in the invaded range could result from historical processes, such as founder and bottleneck events. Traits such as selfing are more likely to preserve the signatures of founder events and influence the genetic diversity in invasive populations. Additionally, clonality seems to be the predominant reproduction system in the invaded range.

Range expansion in plant populations, especially at the colonization front, can be either limited by disproportionately large effects of antagonistic interactions or facilitated by their release. How the strength of antagonistic interactions changes along successional gradients during range expansion is still poorly documented, especially when diverse assemblages of plant antagonists (rodents, invertebrates and birds) combine within interaction networks. We study the changes in individual-based, predispersal seed–pulp predator networks along a colonization gradient in a rapidly expanding Juniperus phoenicea population in Doñana National Park (SW Spain). Additionally, we analysed the role of individual plant traits and neighbourhood attributes in network configuration by using Exponential Random Graph Models. Seven seed–pulp consumer animal species varied significantly in their frequency of interaction and prevalence. While invertebrate species were well-established in old and intermediately mature stands, greenfinch Chloris chloris was dominant at the colonization front. Variable species roles and spread of interactions among individual plants generated changes in the configuration of interactions during plant expansion. Individual plant traits strongly determined the topology of these networks, although with differences between stands. Increasing individual crop size and seeds per cone increased the interaction odds of individual plants, while seed viability showed the opposite effect. The network topology at the colonization front appeared less driven by individual traits, possibly because of the short interaction history of this recently established area. The disproportionately large effect of C. chloris in these recently established stands, potentially resulted in large seed losses during range expansion. Synthesis. Turnover of antagonistic interactions, characterized the colonization front, resulting in more heterogeneous interaction strengths among individual

Child maltreatment is a public health problem with different consequences depending on the form of abuse. Measuring risk and protective factors has been a fertile ground for research, without involving instruments with sufficient evidence of validity. The aim of the study was to gather evidence of validity and reliability of the Inventory Brief Child Abuse Potential (IBCAP) and Protective Factors Survey (PFS) in the Mexican population. The instruments were translated into Spanish. In a non-probabilistic sample of 200 participants, the 7-factor model for the IBCAP [comparative fit index (CFI) = 0.984; root mean square error of approximation (RMSEA) = 0.067] and the 4-factor model for the PFS (CFI = 0.974; RMSEA = 0.061) were confirmed, showing adequate fit indices. Reliability was estimated and evidence of convergent, divergent, and discriminant validity was collected, controlling for effects of social desirability. We also report interpretability statistics of the scores.We achieved solid progress in the development of instrumentation that allows determining the presence or absence of protective and risk factors for child abuse.

We have designed unprecedented cholinesterase inhibitors based on 1-deoxynojirimycin as potential anti-Alzheimer’s agents. Compounds are comprised of three key structural motifs: the iminosugar, for interaction with cholinesterase catalytic anionic site (CAS); a hydrocarbon tether with variable lengths, and a fragment derived from 2-phenylethanol for promoting interactions with peripheral anionic site (PAS). Title compounds exhibited good selectivity towards BuChE, strongly depending on the substitution pattern and the length of the tether. The lead compounds were found to be strong mixed inhibitors of BuChE (IC50 = 1.8 and 1.9 µM). The presumptive binding mode of the lead compound was analysed using molecular docking simulations, revealing H-bond interactions with the catalytic subsite (His438) and CAS (Trp82 and Glu197) and van der Waals interactions with PAS (Thr284, Pro285, Asn289). They also lacked significant antiproliferative activity against tumour and non-tumour cells at 100 µM, making them promising new agents for tackling Alzheimer’s disease through the cholinergic approach.

Introducción: Los estudios gauge permiten ganar información sobre el desempeño de procesos y son de utilidad para control de calidad, así como identificación de fuentes de variación. El objetivo del presente estudio, fue diseñar y analizar sistemas de medición para los modelos de Heckel y Ryshkewitch-Duckworth para caracterizar materiales, a través de estudios Gauge R&R. Método: Estudio Gauge R&R cruzado para evaluar el sistema de medición del peso y estudio Gauge R&R anidado para el sistema de la resistencia a la fractura. Resultados: Ambos estudios cumplieron con los supuestos de normalidad, varianza constante e independencia de los datos, por lo que fue posible determinar la significación de las fuentes de variación (factores) mediante un ANOVA así como su porcentaje de contribución. Para el estudio Gauge R&R cruzado los punzones evaluados contribuyen a la variación de la medición de manera significativa y en un 97,38% de la variación total; los operadores contribuyen en menos del 1% y de manera no significativa y no existió interacción parte-operador. Respecto al estudio Gauge R&R anidado, se identificó que el operador no influyó de manera significativa en la variabilidad de la medición y que ésta es atribuible en un 95% a las diferencias existentes entre las tabletas evaluadas. Conclusiones: Se realizó el diseño, ejecución y análisis de los sistemas de medición, destacando que en ambos estudios la principal fuente de variación fueron las partes evaluadas y que los operadores no contribuyen en la variabilidad de las mediciones, por lo que los estudios pueden usarse para evaluar los modelos matemáticos y durante el control estadístico de un proceso.

Background: Estimating outcrossing/selfing rates and characterizing genetic diversity with microsatellite markers are crucial to understanding the evolution of plant mating systems. Methods and results: We developed, optimized and characterized eight new primer pairs for Centaurium grandiflorum ssp. boissieri and transferred them to three subspecies of Centaurium quadrifolium. Two SSR loci were transferred from Sabatia campestris to the four Centaurium taxa. Polymorphisms, He, Ho and H–W deviations were estimated in two populations of C. grandiflorum ssp. boissieri and in seven individuals each of C. quadrifolium ssp. barrelieri, C. quadrifolium ssp. parviflorum and C. quadrifolium ssp. quadrifolium. A total of 80 individuals was used in these experiments. The number of polymorphic loci varied among species from one to ten. A total of 127 alleles was scored. The average number of alleles per locus was 12.7. He was higher than Ho in all sampled populations. Hardy–Weinberg equilibrium was found for some loci in different species. Conclusions: This is the first report of microsatellites successfully amplified in the whole Centaurium genus. They will be valuable for estimating mating system parameters and genetic diversity and exploring their relationships with the wide variation in flower morphology in the genus, especially anther-stigma separation.

The Sustainable Development Goals (SDGs) re-focused development cooperation on universal and transformative development aimed at improving the quality of life of people in all world regions, while simultaneously conserving natural resources. Critics, however, have correctly questioned whether appropriate policy methods and tools exist for the adequate implementation of transformative development. These challenges are even more significant given that the implementation of the SDGs falls to nation-states. This article asks “Can the transformative development promoted by the SDG’s be achieved through the policy tools presently utilized by nation-states, such as environmental impact assessment (EIA)?” The study responds to this question through a critical examination of EIA in Mexico in relation to mining. Empirical analysis focuses on the proposed Caballo Blanco open-pit mine in Veracruz state. The case can be considered critical because it is often presented as a success, given that a broad coalition of actors prevented the mine from opening through activities directed at EIA. This article questions this narrative because it shows how EIA actually can undermine transformative development through the use of cost-benefit logics. The article concludes that policy coherence for development (PCD) can potentially support EIA as a methodology through which transformative development can be promoted. PCD can improve the “normative effectiveness” of EIA when used as an evaluation criteria. Otherwise, EIA may undermine the implementation of the SDGs which would be comparable to serving soup with a fork.

El libro colectivo Taller de taquimecanografía fue escrito por las escritoras y artistas mexicanas Aura Estrada, Gabriela Jáuregui, Laureana Toledo y Mónica de la Torre. El objetivo es estudiarlo como un conjunto de medios y lenguajes que cuestiona los principios binarios de organización del trabajo intelectual y artístico. Se caracteriza la obra mediante el doble significado del ensamblaje, como técnica artística y como proceso de subjetivación. La obra posee una autoría colectiva en la que la atribución autoral individual se disuelve en una entidad material que produce un ensamblaje de enunciaciones colectivas entre signos y cuerpos, y la materialidad del libro es el dispositivo que los articula., The collective book Taller de taquimecanografía was written by the mexican writers and artists Aura Estrada, Gabriela Jáuregui, Laureana Toledo and Mónica de la Torre. The aim is to explore it as a assemblage of media and languages that challenge the binary principles for the organization of the intelectual and artistic work. The book is characterized through the double meaning of assemblage, as an artistic technique and as process of subjectivation.The book had a collective authorship in which the individual author atribution melts into a collective entity that produces an articulation of collective speech between signs and bodies, and the materiality of the book is the device that articulates them.

El objetivo de este trabajo es analizar la práctica del repartimiento de mercancías en la intendencia de Yucatán. Un proceso iniciado en 1795 por el Cabildo de Campeche muestra varias caras de este sistema comercial después de su prohibición. No continuó con la misma intensidad que antes y cada subdelegado lo adaptó según sus posibilidades, la prioridad fue obtener mejor mano de obra que productos para las haciendas y ranchos que se estaban expandiendo en la región., The objective of this work is to analyze the practice of repartimiento en the Intendancy of Yucatan. A process initiated in 1795 by the Cabildo de Campeche shows several faces of this commercial system after its prohibition. It did not continue with the same intensity as before and each subdelegate adapted it according to his possibilities, the priority was getting better workforce than products for the haciendas and ranches that were expanding in the region.

Beach evening-primrose (Oenothera drummondii subsp. drummondii) is a perennial herb native to the coastal dunes of the Gulf of Mexico and southeastern USA. During the last century, the species was unintentionally introduced into coastal dune systems around the world. The purpose of this study was to explore the means of dispersal of this invasive in the newly established populations on the coastal dunes of Spain and to determine if they contribute significantly to the invasion process. After reconstructing the history of its spread in Spain from available records, we tested whether dispersion by marine currents can be a mechanism of colonization at regional scale, and whether the presence of native vertebrate participate in the expansion process at local scale. Through laboratory experiments, we demonstrated that the seeds of O. drummondii can be dispersed by seawater, since 0.63% present both buoyancy in seawater and subsequent germination after being washed with fresh water. This capacity for dispersal by marine currents could explain both the expansion of the species along the southwestern coast of Spain and the maintenance of its populations following disturbances such as storms. We also demonstrated that Iberian Hares and European Rabbits can disperse the seeds by endozoochory; seeds recovered from faecal pellets of these species were capable of germination (73 and 63%, respectively). Oenothera drummondii has become an invader only in coastal dunes where these dispersers are present, and with no control actions to regulate their populations. In conclusion, O. drummondii is an alien species with varying dispersal methods, polychory. This helps maintain already established populations and disperses seeds at a regional level, depending on the incidence of storms and the presence or absence of rabbits and hares for efficient local seed dispersion. Thus, management actions that restrict marine and animal dispersal likely have the benefit of limiting the invasive pot

Local path planning is important in the development of autonomous vehicles since it allows a vehicle to adapt their movements to dynamic environments, for instance, when obstacles are detected. This work presents an evaluation of the performance of different local path planning techniques for an Autonomous Surface Vehicle, using a custom-made simulator based on the open-source Robotarium framework. The conducted simulations allow to verify, compare and visualize the solutions of the different techniques. The selected techniques for evaluation include A*, Potential Fields (PF), Rapidly-Exploring Random Trees* (RRT*) and variations of the Fast Marching Method (FMM), along with a proposed new method called Updating the Fast Marching Square method (uFMS). The evaluation proposed in this work includes ways to summarize time and safety measures for local path planning techniques. The results in a Lake environment present the advantages and disadvantages of using each technique. The proposed uFMS and A* have been shown to achieve interesting performance in terms of processing time, distance travelled and security levels. Furthermore, the proposed uFMS algorithm is capable of generating smoother routes.

The elastic scattering process for the nuclear reactions induced by the Radioactive Ion Beams 7Be and 8B on a 208Pb target was measured for the first time in the energy range around the Coulomb barrier. Extensive theoretical calculations within the framework of the optical model were performed. An excellent agreement between experimental data and theoretical predictions was achieved for the reaction 7Be + 208Pb, while a comprehensive understanding of the reaction dynamics induced by the more exotic projectile 8B is still far to be reached. Predictions of the cross section for the breakup for both systems will also be given.

Neural networks have enabled great advances in recent times due mainly to improved parallel computing capabilities in accordance to Moore’s Law, which allowed reducing the time needed for the parameter learning of complex, multi-layered neural architectures. However, with silicon technology reaching its physical limits, new types of computing paradigms are needed to increase the power efficiency of learning algorithms, especially for dealing with deep spatio-temporal knowledge on embedded applications. With the goal of mimicking the brain’s power efficiency, new hardware architectures such as the SpiNNaker board have been built. Furthermore, recent works have shown that networks using spiking neurons as learning units can match classical neural networks in supervised tasks. In this paper, we show that the implementation of state-of-the-art models on both the MNIST and the event-based NMNIST digit recognition datasets is possible on neuromorphic hardware. We use two approaches, by directly converting a classical neural network to its spiking version and by training a spiking network from scratch. For both cases, software simulations and implementations into a SpiNNaker 103 machine were performed. Numerical results approaching the state of the art on digit recognition are presented, and a new method to decrease the spike rate needed for the task is proposed, which allows a significant reduction of the spikes (up to 34 times for a fully connected architecture) while preserving the accuracy of the system. With this method, we provide new insights on the capabilities offered by networks of spiking neurons to efficiently encode spatio-temporal information.

Este trabajo se enfoca en el inicio de la explotación del palo de tinte, llamado palo de Campeche o Ek en maya, que está atado en las fuentes documentales del siglo XVI a un conquistador de las huestes de Montejo. Su nombre Marcos de Ayala Trujeque, originario de Toledo, quien formaba parte de los primeros cuarentana y nueve avecindados de la villa de Valladolid en 1542 y que descubrió la manera de hacer tinte observando a sus encomendados., This paper focuses on the beginning of logwood exploitation, called Campeche wood or Ek in Maya which is connected, according to documented sources, to a man from the conquistadores of the army of Montejo. His name is Marco de Ayala Trujeque, originally from Toledo and who was part of the list of forty nine conquistadores in the vicinity of Villa de Valladolid in 1542. He discovered how to make dye by observing the people he had under his charge.

Este artículo examina la relación entre los movimientos sísmicos acaecidos en el Altiplano Occidental de Guatemala en 1765 y la actividad de los volcanes Cerro Quemado y Tajumulco. Con esto en mente, se analizan las afectaciones materiales y las perspectivas sociales que derivaron de estos hechos, prestando atención en las estrategias que desplegaron las autoridades civiles y religiosas para contener la desgracia., This article examines the relationship between the eathquakes in Western Highlands Guatemala and the volcanic eruptions of Cerro Quemado and Tajumulco in 1765. This research paying attention in the material effects and social perspectives from these events, and analyzes the civil and religious strategies to contain misfortune.

The iridium complex 1 based on a metalated CNP ligand containing an imidazolin-2-ylidene fragment has been prepared by treatment of the ligand precursor 4 with Ag2O followed by reaction with [IrCl(COE)2]2. The chlorohydride imidazolidin-2-ylidene complex 6, which is isostructural to 1, was synthetized by reaction of the previously reported dihydride derivative 3 with CH2Cl2. Complexes 1 and 6 exhibit luminescence arising from a 3MLCT/ILCT state involving the metalated CNP ligand, which is particularly intense for 1 in the solid state at 298 K. Furthermore, the reactivity of complexes 1 and 6 towards bases was compared. Deprotonation of 1 with KOtBu produced the selective formation of the dinuclear complex 7; meanwhile, the reaction of 6 led to a complex mixture of products. The same reactions carried out in the presence of PPh3 produced the selective deprotonation of the P-bonded methylene bridges of 1 and 6, yielding the isostructural derivatives 9 and 10. DFT calculations performed on the uNHC-containing tautomers I and II, and the sNHC-based isomers III and IV, showed that the NHC-deprotonated derivatives II and IV are more stable by 3.20 and 2.73 kcal mol–1, respectively, than their P-deprotonated counterparts (I and III). However, a reverse stability order was observed for hexacoordinated tautomers I·L and II·L, and III·L and IV·L (L = PPh3, CO, MeCN). Finally, the catalytic activity of complex 3 in the transfer hydrogenation of ketones has been assessed.

Beaches and foredunes are characterized by being exposed to harsh environmental restrictions mainly due to salt spray, burial by sand and occasional storms. In response to this, plant species from these habitats have adaptations that allow them not only to survive in these environments, but also to recover after the impact of disturbances such as severe storms. In this study, we had the opportunity to study vegetation recovery on the coast of Huelva, Spain, after the impact of a strong winter storm in 2017 which severely affected the vegetation growing on the beach and foredune. Species composition and abundance of vegetation was compared before (2013) and after (2018) the storm hit the coast in 2017. The results show that the effects of the storm were still evident a year later. Native species, mainly perennials, were able to recover almost completely to predisturbance levels. In contrast, the invasive species, Oenothera drummondii, which was abundant before the storm, disappeared from the beach and its presence in the foredune was greatly reduced. Given the forecasts of sea level rise and the increased frequency and intensity of storms, it is necessary to sustain and reinforce the natural coastal sectors where native plant communities maintain the resilience of coastal ecosystems when impacted to these disturbances.

The term Industry 4.0 has been increasing its importance in recent years. This, due to the changes that this term implies in the way in which organizations and supply chains are conceived. Given this, various companies around the world have made efforts to implement the principles of Industry 4.0. However, the way in which each organization conceives this term usually varies in each case of implementation, where a misconception of the term commonly results in the use of resources susceptible to be used in a better way. Due to the above, this paper aims to propose a reference framework for Industry 4.0 and the implications it represents for the current industry in order to contribute to a better understanding of this term. A new definition of Industry 4.0 is proposed in this research.Keywords: Digitization, Fourth Industrial Revolution, Industry 4.0, Smart Factory, Smart Manufacturing. ResumenEl término Industria 4.0 ha ido incrementando su importancia en los últimos años. Esto, debido a los cambios que implica en la manera en cómo se conciben las organizaciones y cadenas de suministro. Ante esto, diversas compañías alrededor del mundo han realizado esfuerzos para implementar los principios de Industria 4.0. Sin embargo, la manera en cómo cada organización concibe este término suele variar en cada caso de implementación, resultando comúnmente una mala concepción del término en la utilización de recursos susceptibles a ser utilizados de mejor manera. Debido a lo anterior, el presente artículo tiene como objetivo proponer un marco de referencia para Industria 4.0 y las implicaciones que representa para la industria actual con el fin de contribuir a un mejor entendimiento de este término. Una nueva definición de Industria 4.0 es propuesta en el presente estudio.Palabras Clave: Cuarta Revolución Industrial, Digitalización, Fábrica Inteligente, Industria 4.0, Manufactura Inteligente.

La colonización española de la región de la Laguna de Términos, en el Golfo de México, se articuló alrededor de la explotación del palo de tinte desarrollada en la segunda mitad del siglo XVIII. A partir de cómo se gestionaron las licencias para el corte de ese preciado árbol, el artículo incursiona por los efectos de la explotación maderera en el ordenamiento territorial de la región basado en la calidad de ser vecino., The Spanish colonization of the region known as Laguna de Términos, in the Gulf of Mexico, was constructed around the exploitation of logwood in the second half of the eighteenth century. From the perspective of how the licenses for the cutting of this valued tree were granted, this article investigates the effects of the logwood harvest on the territorial order of the region based on the Spanish notion of vecino.

Basado en la teoría de los stakeholders y de la masa crítica, este estudio analiza la relación entre la diversidad de género en el consejo y el cumplimiento de Responsabilidad Social Empresarial (RSE) de las empresas cotizadas en Colombia y México. Utilizando un panel de datos compuesto de 477 observaciones durante el periodo 2011-2016, los resultados muestran que a mayor diversidad de género en el consejo, la rentabilidad y el desempeño ambiental y social de la empresa incrementan, mientras que el efecto es negativo para las dimensiones de presencia internacional y el nivel de endeudamiento. Sin embargo, cuando hay una presencia de tres mujeres o más en el consejo, el desempeño en las dimensiones ambiental y social se incrementa. El tamaño y la independencia del consejo mejoran el cumplimiento de la RSE. En este sentido, los resultados apoyan la teoría de la masa crítica, que afirma que tres o más mujeres pueden influir significativamente en el desempeño corporativo de la empresa. Este trabajo tiene implicaciones prácticas para los responsables de emitir las políticas de género y RSE en Latinoamérica.

The elastic scattering of the weakly bound radioactive nuclei B8 and Be7 from a Pb208 target was measured for the first time in the energy range around the Coulomb barrier. The data were analyzed using the optical model and the continuum discretized coupled channels (CDCC) formalisms. The reaction cross sections extracted from the optical model fits clearly indicate a remarkably enhanced reaction probability for the very weakly bound B8 (Sp=137.5keV) compared to similar mass nuclei interacting with the same target nucleus. CDCC calculations assuming a He3+He4 cluster model well described the Be7 experimental elastic scattering angular distributions, whereas the use of a Be7+p cluster model of B8 with an inert Be7 core gave a relatively poor description of the corresponding experimental data, suggesting that this model may be too simplistic and the possibility of core excitation should not be ignored.

Perforated solar screens (PSS) are an important consideration in building façade design due to its contribution to sustainability through daylighting. PSS design requires the consideration of many potential design alternatives that involves a large number of simulations. This paper presents a methodology in which the orthogonal and listing methods are integrated to predict a set of optimum PSS design variables to enhance the Daylight Availability in office buildings located in Seville, Spain. An orthogonal array is selected to perform a transverse comparison of the simulation factors mean effects and to find their statistical significance. Then, a standard level is fixed and used for further detailed analysis of a greater number of factor levels, measuring their daylighting contributions. The main advantage of the integrated method is the reduction of the number of simulations from 720 to 32, so it could save time considerably and would help designers to make early-design-stage decisions. With the optimization, the actual daylit area increased by 29-57% and the over lit area reduced by 36-57%, relative to reference models with no PSS.

This paper examines the relationship between the Daylight Availability (DAv) metric and annual energy consumption. DAv was established as a means of describing indoor daylight sufficiency both for research and practical purposes. To balance daylighting with energy concerns, the specific amount of daylight sufficiency within a space should neither be too low; nor should it be excessive. However, there is little if any notion of what the relationship between a DAv area and the energy used on-site to supply the artificial lighting, heating and cooling systems might be. The aim of this research is to determine if one or more of the DAv areas predicted on the workplane could serve as a proxy for the overall building energy consumption (lighting plus heating and cooling). The office setting is designed to offer a wide range of daylight exposures, depending on the orientation of the fully-glazed façade and that of the perforated solar screen configuration. Results indicated a strong linear relationship between the overlit area and the cooling energy use. Moreover, confining the overlit area to less than 40% at South and less than 50% at North, East and West could help limit the overall energy consumption to less than 120 kWh/m2-year.

This paper proposes a novel multiplierless comb compensation filter, which has the absolute passband deviation less than 0.1 dB in the wide passband. The compensator consists of a cascade of two simple filter sections, both operating at a low rate. The magnitude characteristics of the two-component filters are synthesized as sinewave functions, in which the main design parameters correspond to the amplitudes of sinewave functions. A systematic procedure is followed to select synthesis parameters, which depend only on the number of cascaded comb filters. In particular, they are independent of the decimation factor. Comparisons with comb compensators from the literature illustrate the benefits of the proposed design.

On fully-glazed building façades perforated solar screens (PSS) are often used as an outer skin in order to reduce energy consumption and to solve issues such as visual appearance. However, not only must PSS control solar radiation but they must also provide adequate daylight levels, thus requiring a balanced solution. Currently, daylighting simulation software enables us to perform efficient daylight analysis of spaces with PSS. Notwithstanding this, current energy simulation software such as EnergyPlus cannot deal well with such geometry directly, making the thermal evaluation of PSS an infeasible task. This paper presents a methodology for achieving an integrated analysis of daylighting and energy consumption of spaces with PSS during the design stage. Such methodology provides daylight analysis through DIVA, and thermal analysis through EnergyPlus via DIVA/Grasshopper/Archsim. The aim is to optimise the dual performance of a balanced PSS solution through controlling its perforation percentage, matrix and shape, by using the orthogonal arrays (DOA) statistical method. DOA method is efficient in reducing the number of simulations derived from the combination of the aforementioned variables, and in identifying the optimal PSS configuration. In comparison to a non-optimised façade located in Seville, Spain, the predicted optimal PSS achieved a 50% increase in the actual daylit area and a 55% reduction in the total energy demand.