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La población de caninos ferales representa una problemática para la salud pública y la seguridad de las personas en la calle, representando una fuente de enfermedades y accidentes que afectan a la sociedad en conjunto. En el estado de Guanajuato se han fundado diversos centros de atención a caninos en los municipios con el fin de controlar las poblaciones ferales y brindarles una segunda oportunidad, aplicando procedimientos tales como campañas de esterilización, captura de perros en vía pública, programas de adopción y finalmente la eutanasia, cada una contribuye a solucionar un problema que se ha visto aumentado en tiempos de pandemia.

Centipedes coordinate body and limb flexion to generate propulsion. On flat, solid surfaces, the limb-stepping patterns can be characterized according to the direction in which limb-aggregates propagate, opposite to (retrograde) or with the direction of motion (direct). It is unknown how limb and body dynamics are modified in terrain with terradynamic complexity more representative of these animal's natural heterogeneous environments. Here, we investigated how centipedes that use retrograde and direct limb-stepping patterns, Scolopendra polymorpha and Scolopocryptops sexspinosus, respectively, coordinate their body and limbs to navigate laboratory environments which present footstep challenges and terrain rugosity. We recorded the kinematics and measured the locomotive performance of these animals traversing two rugose terrains with randomly distributed step heights and compared the kinematics with those on a flat frictional surface. Scolopendra polymorpha exhibited similar body and limb dynamics across all terrains and a decrease in speed with increased terrain rugosity. Unexpectedly, when placed in a rugose terrain, S. sexspinosus changed the direction of the limb-stepping pattern from direct to retrograde. Further, for both species, traversal of these rugose terrains was facilitated by hypothesized passive mechanics: upon horizontal collision of a limb with a block, the limb bent and later continued the stepping pattern. Although centipedes have many degrees of freedom, our results suggest these animals negotiate limb–substrate interactions and navigate complex terrains leveraging the innate flexibility of their limbs to simplify control.

Robophysical experiments on flat and obstacle-rich environments

The environmental (climate change), economic (recessions), and social (increase in poverty and inequality) crises have forced the need for a change of model and the development of global strategies to counteract their negative effects and orient towards a type of economy that is low in carbon emissions, efficient in the use of resources and energy, socially inclusive, preventive in the loss of biodiversity and ecosystem services and that allows achieving sustainable development, which is how the concept of green economy arises. With a quantitative approach, using official databases and based on the Organization for Economic Co-operation and Development (2011) green growth framework, a Green Economic Growth Index for Mexico was constructed under the relativization function, which was estimated at the national, state, and geographic region levels, allowing for a deeper understanding of the green economy in the country. The results show an average national performance (0.4746), with the dimensions "Economic, demographic and social context for sustainable development," "Environmental dimension of quality of life," and "Natural asset base" having the best scores, while the dimension "Productivity of environmental resources and the economy" and "Economic opportunities and policy response" have the lowest scores. The analysis of variance results shows statistically significant differences by geographic regions, which calls for developing public, environmental, energy, and productive policies that consider the particular conditions of the country's regions.

Code for rugose terrain generation

PurposePrevious studies on hospital supply chain performance have attempted to measure the performance of the hospital supply chain either by the measurement of performance indicators or the performance of specific activities. This paper attempts to measure the internal hospital supply chain's performance indicators to find their interdependencies to understand the relationship among them and identify the key performance indicators for each of those aspects of the logistics process toward improvement.Design/methodology/approachIn this research, a systematic assessment and analysis method under vagueness is proposed to assess, analyze and measure the internal health care performance aspects (HCPA). The proposed method combines the group Decision-Making and Trial Evaluation Laboratory (DEMATEL) method and rough set theory.FindingsThe study results indicate that the most critical aspects of hospital supply chain performance are completeness of treatment, clinical care process time and no delay in treatment.Originality/valueThe causal relationship from rough-DEMATEL can advise management officials that to improve the completeness of treatment toward patient safety, clinical care process time should be addressed initially and with it, patient safety aspects such as free from error, clinical care productivity, etc. should be improved as well. Improvement of these aspects will improve the other aspects they are related to.

Los sistemas de bicicletas compartidas en la literatura se conocen como BSS por sus siglas en ingles ( Bike Shared System ), en este articulo se analiza el BSS de la ciudad de Medellin - Colombia llamado “EnCicla”. El objetivo es conocer el comportamiento global del sistema para poder identificar las horas de mayor uso, las estaciones mas usadas y los tipos de comportamiento que se presentan. Se han recolectado datos del funcionamiento del sistema, con los cuales se ha realizado el procesamiento y analisis categorizado por ubicacion y franjas horarias. Con los datos recolectados y el analisis estadistico realizado se identificaron las estaciones criticas dentro del sistema, los patrones de comportamiento de las cada una de ellas, los picos horarios, los maximos, minimos y variabilidad de ocupacion en promedio; con lo cual se genera el desafio de modelar, simular y mejorar el funcionamiento del sistema, asi como evaluar politicas de operacion y su implementacion. Palabras clave: Sistemas de Bicicletas Compartidas, Analisis de Informacion, Sistemas de Transporte, Sistemas Dinamicos. doi: https://doi.org/10.36825/RITI.09.18.004

We have studied the multicaloric properties of a Ni-Mn-Ga-Cu alloy. In this alloy, application of magnetic field and uniaxial stress shift its martensitic transition towards higher temperatures which results in synergic magnetocaloric and elastocaloric effects. By a proper numerical treatment of the calorimetric curves obtained under applied magnetic field and uniaxial stress we have obtained the entropy S(T,μ0H,σ) as a function of the magnetic field, uniaxial stress, and temperature over the whole phase space under study. We have determined the different entropy contributions to the multicaloric effect in this alloy, and noticeably we have evidenced the role played by the interplay between magnetic and vibrational degrees of freedom. A comparison between single caloric and multicaloric effects shows that appropriate combinations of magnetic field and stress reduce the magnitude of the specific field required to obtain a given value of the isothermal entropy and adiabatic temperature changes. For example, at 299 K, to achieve an entropy change (ΔS) of −14 J kg−1K−1, a magnetic field of ∼2.5 T or a uniaxial stress of 19 MPa are required, while a combination of dual fields of (1 T, 12 MPa) yields to the same value of ΔS. Moreover, the maximum adiabatic temperature change is enlarged up to 9.4 K by the dual fields, higher than the value obtained by a single field (∼7 K). The advantage of multicaloric effect is particularly relevant at low magnetic fields which are achievable by permanent magnets. Our findings open new avenues for using multicaloric materials in novel refrigeration technologies.

Centipedes coordinate body and limb flexion to generate propulsion. On flat solid surfaces, the limb-stepping patterns can be characterized according to the direction in which limbaggregates propagate, opposite to (retrograde) or with the direction of motion (direct). It is unknown how limb and body dynamics are modified in terrain with terradynamic complexity more representative of their natural heterogeneous environments. Here, we investigated how centipedes that use retrograde and direct limp-stepping patterns, S. polymorpha and S. sexspinosus, respectively, coordinate their body and limbs to navigate laboratory environments which present footstep challenges and terrain rugosity. We recorded the kinematics and measured the locomotive performance of these animals traversing two rough terrains with randomly distributed step heights and compared the kinematics to those on a flat frictional surface. S. polymorpha exhibited similar body and limb dynamics across all terrains and a decrease in speed with increased terrain roughness. Unexpectedly, when placed in a rough terrain, S. sexspinosus changed the limb-stepping pattern from direct to retrograde. Further, for both species, traversal of rough terrains was facilitated by hypothesized passive mechanics: upon horizontal collision of a limb with a block, the limb passively bent and later continued the stepping pattern. While centipedes have many degrees of freedom. our results suggest these animals negotiate limb-substrate interactions and navigate complex terrains, by offloading complex control and leveraging the innate flexibility of their limbs.

A complete simulcast on digital TV (DTV) can be complex to implement in some scenarios, such as when the network bandwidth has many limitations. A common solution in such scenarios is to limit the number of duplicate programmes in the simulcast to a minimum. However, this practice slows down the migration to a new generation. This article analyses the causes of this delay and proposes a technique to improve the efficiency of the simulcast. Focusing on the migration from MPEG-2 SD to H.264 HD broadcasts in DVB-T networks, the article presents an efficient solution that can accelerate the transition period.

The blood-brain barrier (BBB) regulates molecular and cellular entry from the cerebrovasculature into the surrounding brain parenchyma. Many diseases of the brain are associated with dysfunction of the BBB, where hypoxia is a common stressor. However, the contribution of hypoxia to BBB dysfunction is challenging to study due to the complexity of the brain microenvironment. In this study, we used a BBB model with brain microvascular endothelial cells and pericytes differentiated from iPSCs to investigate the effect of hypoxia on barrier function. We found that hypoxia-induced barrier dysfunction is dependent upon increased actomyosin contractility and is associated with increased fibronectin fibrillogenesis. We propose a role for actomyosin contractility in mediating hypoxia-induced barrier dysfunction through modulation of junctional claudin-5. Our findings suggest pericytes may protect brain microvascular endothelial cells from hypoxic stresses and that pericyte-derived factors could be candidates for treatment of pathological barrier-forming tissues.

Locomotion is typically studied either in continuous media where bodies and legs experience forces generated by the flowing medium or on solid substrates dominated by friction. In the former, centralized whole-body coordination is believed to facilitate appropriate slipping through the medium for propulsion. In the latter, slip is often assumed minimal and thus avoided via decentralized control schemes. We find in laboratory experiments that terrestrial locomotion of a meter-scale multisegmented/legged robophysical model resembles undulatory fluid swimming. Experiments varying waves of leg stepping and body bending reveal how these parameters result in effective terrestrial locomotion despite seemingly ineffective isotropic frictional contacts. Dissipation dominates over inertial effects in this macroscopic-scaled regime, resulting in essentially geometric locomotion on land akin to microscopic-scale swimming in fluids. Theoretical analysis demonstrates that the high-dimensional multisegmented/legged dynamics can be simplified to a centralized low-dimensional model, which reveals an effective resistive force theory with an acquired viscous drag anisotropy. We extend our low-dimensional, geometric analysis to illustrate how body undulation can aid performance in non–flat obstacle-rich terrains and also use the scheme to quantitatively model how body undulation affects performance of biological centipede locomotion (the desert centipede Scolopendra polymorpha ) moving at relatively high speeds (∼0.5 body lengths/sec). Our results could facilitate control of multilegged robots in complex terradynamic scenarios.

Background School-based COVID-19 testing is a potential strategy to facilitate the safe reopening of schools that have been closed due to the pandemic. This qualitative study assessed attitudes toward this strategy among four groups of stakeholders: school administrators, teachers, parents, and high school students. Methods Focus groups and interviews were conducted in Los Angeles from December 2020 to January 2021 when schools were closed due to the high level of COVID transmission in the community. Results Findings indicated similarities and differences in attitudes toward in-school COVID-19 testing. All groups agreed that frequent in-school COVID-19 testing could increase the actual safety and perceived safety of the school environment. School administrators expressed pessimism about the financial cost and logistics of implementing a testing program. Parents supported frequent testing but expressed concerns about physical discomfort and stigma for students who test positive. Teachers and parents noted that testing would prevent parents from sending sick children to school. Students were in favor of testing because it would allow them to return to in-person school after a difficult year of online learning. Conclusion In-school COVID-19 testing could be a useful component of school reopening plans and will be accepted by stakeholders if logistical and financial barriers can be surmounted and stigma from positive results can be minimized.

As the COVID-19 pandemic shakes the human society, most fields had to adapt to online systems in order to keep operating. Such is the case of the Education field, where e-learning became the main (and sometimes the only) tool available to ensure that teaching activities could continue. This work analyzes the case of a cybersecurity program taught online in Chile from 2019 to this day. The available data allowed us to observe some of the impacts that the pandemic had on the student’s dropout levels, highlighting some difference between the early months of the pandemic, versus later periods in time.

This article presents the results of the analysis of the studies of the operation of a modified IEEE-13 distribution feeder, which was built to scale in the laboratory at Universidad del Norte. In this article, we show the cases of the operating regimes of the modified IEEE-13, before the different levels of wind energy penetration. The modified IEEE-13 distribution feeder was built taking into account that each of the scaled modules and their generator-load will work under the conditions of the Universidad del Norte laboratory. An experimental methodology was used to compare the results obtained in the actual scaled model with the results of the simulations in specialized programs. The conclusions of the article show the wind energy that can be injected into an electrical system with conventional power generation so that it can maintain its operation complying with the current regulatory framework.

The structural complexity of the understory layer of forests or shrub layer vegetation in open shrublands affects many ecosystem functions and services provided by these ecosystems. We investigated how the basal area of the overstory layer, annual and seasonal precipitation, annual mean temperature, as well as light availability affect the structural complexity of the understory layer along a gradient from closed forests to open shrubland with only scattered trees. Using terrestrial laser scanning data and the understory complexity index (UCI), we measured the structural complexity of sites across a wide range of precipitation and temperature, also covering a gradient in light availability and basal area. We found significant relationships between the UCI and tree basal area as well as canopy openness. Structural equation models (SEMs) confirmed significant direct effects of seasonal precipitation on the UCI without mediation through basal area or canopy openness. However, annual precipitation and temperature effects on the UCI are mediated through canopy openness and basal area, respectively. Understory complexity is, despite clear dependencies on the available light and overall stand density, significantly and directly driven by climatic parameters, particularly the amount of precipitation during the driest month.

In a broad sense, Machine Learning (ML) is the performance optimization in a certain task through computational means, following a certain criterion and using referential data and/or past results from previous iterations. ML is a subset of Artificial Intelligence (AI) and has attracted a substantial amount of research during the last decades. This blooming subject led to the statement of different definitions for classifications, criteria, algorithms and so on. This paper summarizes these different definitions and proposes a homologation between them, providing an unified vision for each definition.

Diet selection and performance of Criollo Chaqueno and Brahman × Criollo Chaqueno were studied in three seasons in the dry forests of the Bolivian Chaco using direct observations. During the dry season (DS) and the rainy season (RS), the Criollo cattle diet consisted of a higher proportion (P 0.05) for the crossbreds. Other than for the Criollos, the body weight of the crossbreds decreased (P < 0.05) from the DS to the transition period. Especially during the DS, Criollos made more use of forage resources from shrubs and trees and thus, seem to be better adapted to year-round forest grazing compared with the crossbreds.

Supplying electricity to populations without full access requires cost-effective, distributed sources of electricity generation. Diesel generators are a popular electricity source because of their low capital costs, but they can have high operating costs. Little data exist regarding the real-world behavior and operating costs of installed diesel microgrids. We report on the energy delivery and fuel consumption in three diesel microgrids in the Lake Sentani region of Papua, Indonesia. We found that these generators are operated below their capacity and that the fuel used per unit of electricity delivered can be over five times greater than expected based on published values. These estimations of specific fuel consumption suggest that nominally electrified areas are paying high costs for poor reliability, but cost-effective improvements are possible.

A common operation on strings is to calculate a value of similarity. The longest common subsequence (LCS) is a measure of similarity between two sequences. An extension of LCS measure is the constrained longest common subsequence (CLCS). The CLCS consists of calculating the LCS of two sequences, and it is a supersequence of a constrained sequence. This paper is an experimental evaluation of the most important CLCS algorithms. The implemented algorithms have a similar performance and were tested with different kinds of random strings belonging to the alphabets: generated uniformly at random (4, 10, 20, 32, 48 and 64 characters) and English text (239 characters). This study could help in selecting optimal algorithms for a given problem.

In this work, a new approach is proposed for getting a solution of path-planning for mobile robot based on cubic Bezier curve and adaptive particle swarm optimization (A2PSO). Paths generated using a cubic Bezier curve are optimized globally through the A2PSO algorithm. The A2PSO algorithm is significantly more powerful than conventional PSO algorithm. Our approach was successful in determining the shortest path in several environments full of obstacles compared to the performance of the conventional PSO.

This paper summarizes the impact of soil/dirt in solar-panel performance in the Colombian Caribbean Region. The corresponding experiment compares the performance of two identical solar panels, which are subjected to different scenarios. The objective of this research is, to categorize or establish on site solar-radiation ranges in order to estimate the actual solar-panel efficiency compared to 1000 W/m2. The maximum power point is calculated using an I vs V transfer function approximation. The soiling related maximum-power-point impact analysis is carried out with a complete Multivariate Analysis of Variance (ANOVA) considering three fundamental factors: dirt/particles, solar radiation and day. According to experimental results, the soiling effect in the solar-panel efficiency reduction has been estimated as up to 6% during times of the day with the maximum solar radiation; while for lower radiations, the effect decreases exponentially becoming negligible on the available electric power. Thus, empirically it is shown that the effect of dirt/particles is significant from a clean solar-panel to one with light accumulation, but such a negative effect rapidly diminishes as accumulation changes from light to heavy. Therefore, it is suggested that once some dirt accumulates on a panel, a cleaning procedure can wait until the particle accumulation becomes heavy. Thus, this study can become a tool that solar-power-plant operators can employ to estimate the trade-off between photovoltaic-system power efficiency and its financial viability. RESUMEN Este artículo analiza el efecto del material particulado sobre el rendimiento de paneles solares en la Región Caribe Colombiana. Durante el experimento se compara el rendimiento de dos paneles solares identicos sometidos a diferentes escenarios. El objetivo es categorizar y establecer rangos de radiacion solar para estimar su eficiencia comparado con la de 1000 W/m2. El máximo punto de potencia es calculado usando la aproximación de la curva de transferencia I vs V, para luego analizar el impacto de la suciedad a través de un análisis de varianza multifactorial completo (ANOVA) considerando tres factores fundamentales: suciedad/partículas, radiación solar y día. Según los resultados, se estima que el efecto de la suciedad en la eficiencia decae hasta un 6% durante las horas del día con la máxima radiación solar; para radiaciones menores, el impacto en la eficiencia disminuye exponencialmente, lo que implica que la suciedad puede ser insignificante de acuerdo con la potencia disponible. Este estudio revela que el efecto de la suciedad es significativo cuando el panel pasa de limpio a ligeramente sucio, pero este efecto disminuye rápidamente cuando la acumulación cambia de ligera a pesada. Así, se sugiere que una vez el panel tenga suciedad acumulada, los procedimientos de limpieza esperen hasta que la acumulación sea pesada. Así, este estudio se convierte en una herramienta para estimar la relación entre la eficiencia energética de los sistemas fotovoltaicos y su viabilidad financiera.