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In late 2021 and early 2022, CEMLA conducted a thorough survey involving 12 central banks to analyze key aspects related to the potential implementation of a Central Bank Digital Currency (CBDC). The findings revealed prevalent issues and objectives regarding digital payments in the region, as well as promising avenues for central bank involvement. However, it highlighted the challenges of creating a universal CBDC framework due to significant disparities among neighboring countries. Nonetheless, the collaborative research approach promises valuable insights for future efforts. To protect participant anonymity, each country’s responses were anonymized with randomly assigned letters.The survey extensively examined awareness and understanding of CBDCs across diverse stakeholders in Latin American nations, including the general public, corporations, and financial institutions. These insights could shape educational campaigns and communication strategies, enabling policymakers and central banks to effectively share information about CBDCs.Moreover, this research effort sheds light on public perceptions, expectations, and concerns about CBDCs in Latin America. By exploring various dimensions such as awareness, interest, adoption potential, concerns, preferences, and regulatory considerations, the survey offers a comprehensive understanding of the CBDC landscape in the region. This holistic approach provides valuable insights for policymakers, central banks, and stakeholders to navigate the complexities of CBDC implementation effectively and responsibly.

Abstract Optical interference filters (OIFs) are vital components for a wide range of optical and photonic systems. They are pivotal in controlling spectral transmission and reflection upon demand. OIFs rely on optical interference of the incident wave at multilayers, which are fabricated with nanometer precision. Here, we demonstrate that these requirements can be fulfilled by inkjet printing. This versatile technology offers a high degree of freedom in manufacturing, as well as cost-affordable and rapid-prototyping features from the micron to the meter scale. In this work, via rational ink design and formulation, OIFs were fully inkjet printed in ambient conditions. Longpass, shortpass, bandpass, and dichroic OIFs were fabricated, and precise control of the spectral response in OIFs was realized. Subsequently, customized lateral patterning of OIFs by inkjet printing was achieved. Furthermore, upscaling of the printed OIFs to A4 size (29.7 × 21.0 cm²) was demonstrated.

Social networks have captured the attention of many people worldwide. However, these services have also attracted a considerable number of malicious users whose aim is to compromise the digital assets of other users by using messages as an attack vector to execute different types of cyberattacks against them. This work presents an approach based on natural language processing tools and a convolutional neural network architecture to detect and classify four types of cyberattacks in social network messages, including malware, phishing, spam, and even one whose aim is to deceive a user into spreading malicious messages to other users, which, in this work, is identified as a bot attack. One notable feature of this work is that it analyzes textual content without depending on any characteristics from a specific social network, making its analysis independent of particular data sources. Finally, this work was tested on real data, demonstrating its results in two stages. The first stage detected the existence of any of the four types of cyberattacks within the message, achieving an accuracy value of 0.91. After detecting a message as a cyberattack, the next stage was to classify it as one of the four types of cyberattack, achieving an accuracy value of 0.82.

Abstract Background Agri-silvicultures (ASC) are biocultural practices procuring either the maintenance of wild diversity in predominantly agricultural spaces or introducing agrobiodiversity into forests. In the Mesoamerican region, ASC contribute to food sovereignty and territorial conservation and provide strategies for dealing with global changes. Previous inventories of ASC identified gaps in information about these systems in the Mexican Arid America region. This article raises the general question: How have human interactions between cultural, wild, and domesticated biodiversity in this territory? The particular questions in this paper are: (i) How have historical processes shaped human interactions between wild and domesticated biodiversity in the region? and (ii) What types of agri-silvicultures have emerged in Mexican Arid America since these relationships? Methods We trace a methodological border where archaeologists have identified the Mesoamerican region to define our study area as Arid America northern of this line in Mexico. We analyzed agriculturalization processes in Arid America through a historical review. Then, we carry out an inventory of Arid America ASC based on academic papers and other documented experiences. We constructed a spatial database and a typology to understand what kinds of agri-silviculture occur in the region. Results We identified several pre-Hispanic agri-silvicultural practices in the region, like hunting, fishing, terraces, gathering, and irrigation systems. The cultivation of native species of maize, beans, and squash even was registered. The Spanish colonization forced the agriculturization in arid northern Mexico, where itinerant hunting-gathering patterns predominated. In the twentieth century, the Green Revolution adopted this area as the principal setting for industrialized agriculture. The industrialized irrigated systems expansion and other political strategies provoked the simplification of productive landscapes. The practices that integrate wild and agricultural diversity systems were marginalized and invisibilized in such a context. Our research group proposes seven types of agri-silvicultural systems (natives agrisilvicultures, the oases agroforestry, Mesquite and Huisache ASC, homegardens and other traditional forms of agroforestry or agri-silvicultures). These agri-silvicultures provide food, medicine, fodder, and other contributions, as income to the families that practice them and protect native and exotic species. Discussion and conclusion The agriculturization of the arid environments initiated during Spanish colonization and the subsequent modernizing projects shaped dominant actors and ideologies in the arid north of Mexico. However, aridity has favored ancestral and agroecological relationships between cultures and biodiversity, emerging and subsisting Arid American agri-silvicultures. These agri-silvicultures deserve to be understood, adopted, and adapted to new contexts. They could be essential alternatives in the context of environmental changes.

Around 70 million people worldwide are affected by epilepsy, a neurological disorder characterized by non-induced seizures that occur at irregular and unpredictable intervals. During an epileptic seizure, transient symptoms emerge as a result of extreme abnormal neural activity. Epilepsy imposes limitations on individuals and has a significant impact on the lives of their families. Therefore, the development of reliable diagnostic tools for the early detection of this condition is considered beneficial to alleviate the social and emotional distress experienced by patients. While the Bonn University dataset contains five collections of EEG data, not many studies specifically focus on subsets D and E. These subsets correspond to EEG recordings from the epileptogenic zone during ictal and interictal events. In this work, the parallel ictal-net (PIN) neural network architecture is introduced, which utilizes scalograms obtained through a continuous wavelet transform to achieve the high-accuracy classification of EEG signals into ictal or interictal states. The results obtained demonstrate the effectiveness of the proposed PIN model in distinguishing between ictal and interictal events with a high degree of confidence. This is validated by the computing accuracy, precision, recall, and F1 scores, all of which consistently achieve around 99% confidence, surpassing previous approaches in the related literature.

This article aims to analyze social inequality and public security in Mexicali Metropolitan Area from a Human Security approach. The research methodology, carried out in the summer of 2021, is mix methods, with qualitative, quantitative, and cartographic technics. It is based on official data, international organizations reports, media outlets while Google Earth and Mapinfo are mapping tools. The document is divided into the following sections: introduction, conceptual framework, methodology, and qualitative and quantitative description of social inequality and insecurity in the Mexicali Metropolitan Area (MMA). Subsequently, the main argument is addressed, supported by statistics and thematic maps. Finally, the closing considerations are presented.

Let n, m ∈ N with m ≤ n and X be a metric continuum. We consider the hyperspaces Cn(X) (respectively, Fn(X)) of all nonempty closed subsets of X with at most n components (respectively, n points). The (n, m)−fold hyperspace suspension on X was introduced in 2018 by Anaya, Maya, and Vázquez-Juárez, to be the quotient space Cn(X)/Fm(X) which is obtained from Cn(X) by identifying Fm(X) into a one-point set. In this paper we prove that Cn(X)/Fm(X) contains an n−cell; Cn(X)/Fm(X) has property (b); Cn(X)/Fm(X) is unicoherent; Cn(X)/Fm(X) is colocally connected; Cn(X)/Fm(X) is aposyndetic; and Cn(X)/Fm(X) is finitely aposyndetic

Este artículo documenta los resultados de un estudio comparado, de tipo cualitativo, desarrollado en el periodo 2018-2020 en el istmo de Tehuantepec (Oaxaca, México) en torno a tres negociaciones para instalar tres parques eólicos que se encuentran cancelados. Nuestra investigación se apoya en entrevistas, minutas de asambleas, documentos jurídicos, amparos y notas de prensa. Nuestro análisis muestra cómo las prácticas autoritarias ejercidas en la negociación recaen sobre la transición energética, al gestar un clima de percepciones negativas que se tradujeron en una desconfianza e inconformidad que promovieron una oposición social y jurídica hacia los proyectos eólicos. Todo ello afectó la viabilidad de los procedimientos de negociación y consulta formales, como el establecido en el C-169 de la Organización Internacional del Trabajo y estancó la transición energética en la región.

En este artículo se hace un esfuerzo teórico para enfatizar la complementariedad del reduccionismo y el enfoque de sistemas. Pues bien, la tradición científica por mucho tiempo creyó que para comprender algo, la mejor forma era dividiéndolo, es decir, separar sus partes para determinar como funcionan y a partir de ello, obtener conclusiones de los hechos observados. Sin embargo, el enfoque de sistemas es una forma de entender las relaciones y el contexto que, por supuesto, está interesado en las partes, pero principalmente en términos de cómo dan lugar y mantienen en existencia una nueva entidad que es el todo. Por lo tanto, ambos enfoques son complementarios.

Peer-to-Peer (P2P) networks have emerged as potential solutions to issues that cause inefficient download times in networks because they can use the resources in the entire network, allowing nodes to act both as servers and clients simultaneously. Commonly, P2P networks use radio frequency (RF) to communicate among nodes; however, light fidelity (LiFi) has been developed as an alternative to wireless fidelity (WiFi) systems due to some advantages such as great speed (up to 1 Tbps), a high level of security, and less saturated channels in unlicensed bandwidth, making it ideal for RF-sensitive environments and networks with static nodes, since LiFi systems require a high node alignment level to enable efficient communication. In this article, we develop a mathematical model that captures the dynamics of LiFi- and WiFi-based P2P networks in static environments to allow for adequate LiFi links in managed conditions where the content is distributed from a single source node to the rest of the peers through different architectures. For the services considered in our work, we compare the performance of P2P networks using WiFi 7 and LiFi 2.0 technologies to provide clear quantitative numerical results that allow for adequate selection between these systems. Also, we validate our mathematical results through extensive simulations.

El objetivo de la investigación es analizar el tráfico de armas de fuego de Estados Unidos hacia México y su correlación con la violencia homicida en el estado fronterizo de Baja California en el periodo 2013-2020. La metodología es inductiva debido a que observa y registra la información disponible de la incautación de armas. También es exploratoria porque el tráfico de armas de fuego se ha mantenido en la discusión pública pero poco se ha analizado desde la perspectiva teórica del diseño de la agenda e implementación de las políticas públicas. Los resultados plantean que las lagunas en el marco normativo del control de armas de fuego en México incentivan oportunidades para que la delincuencia organizada trafique armas generando espirales de violencia en territorios como Baja California. Existen limitaciones en la disponibilidad de información, pero la perspectiva teórica utilizada permite desarrollar y comprobar la hipótesis de la investigación.

El presente artículo analiza la política de prevención del delito implementada durante la administración del presidente mexicano Enrique Peña Nieto (2012-2018). Se utilizan las teorías del nuevo institucionalismo y de las fallas de gobierno para argumentar que la falta de resultados en la política de seguridad en el país en dicho sexenio se debió a tres factores fundamentales: los problemas inherentes al suministro burocrático, los problemas de implementación y la descentralización política en el país. Se concluye que dicha falta de resultados evidenció, por un lado, la cooperación de los Gobiernos subnacionales en políticas prioritarias del Gobierno central, como la aprobación de las llamadas reformas estructurales, y por otro, la poca coordinación de los distintos niveles de gobierno ante la violencia e inseguridad, que terminó atomizada al final del periodo.

La amenaza que representa la inseguridad pública en América Latina ha conllevado que muchos de los gobiernos asolados por ella recurran a las políticas de militarización. En el caso de México, el gobierno creó la Guardia Nacional para pacificar el país. El objetivo del artículo es responder la pregunta ¿por qué, pese a los argumentos y posturas de diferentes actores nacionales e internacionales, la Administración Federal en México (2018-2024) decidió crear una Guardia Nacional para combatir y reducir los índices de violencia? El estudio emplea un método explicativo y utiliza información del Banco Mundial, el Instituto Nacional de Estadística y Geografía (INEGI), el Fórum Brasileño de Seguridad Pública, World Prision Brief, el Índice de Paz Global, y el Secretariado Ejecutivo del Sistema Nacional de Seguridad Pública (SESNSP). La teoría de las políticas públicas en democracia permite explicar la importancia del desarrollo de esta última para comprender el diseño y los resultados de las primeras. Se toman como referencia los casos de Brasil y Colombia, países que han recurrido a estrategias de militarización (pero con resultados distintos), donde la variable ha sido el gasto militar. En ese ámbito, México está muy por debajo de los dos países aludidos. Abstract The threat posed by public insecurity in Latin America has led many of the governments affected by this problem to resort to militarization policies. In the case of Mexico, the government created the National Guard to pacify the country. The purpose of this article is to answer the question why, despite the arguments and positions of different national and international actors, the Federal Administration in Mexico (2018-2024) decided to create a National Guard to combat and reduce the rates of violence? The study uses an explanatory method and bases on information from the World Bank, the National Institute of Statistics and Geography (INEGI), the Brazilian Public Security Forum, the World Prision Brief, the Global Peace Index, and the Executive Secretariat of the National Public Security System (SESNSP). The theory of public policies in democracy allows to explain the importance of the development of the latter to understand the design and results of the former. The cases of Brazil and Colombia, countries that have resorted to militarization strategies (but with different results), where the variable has been military spending, are taken as reference. In that area, Mexico is well below the two countries mentioned.

En este artículo se presenta el modelo matemático base de la reflectometría hexaportal. Con una intención didáctica, se explica brevemente la historia de la reflectometría hexaportal y enseguida se detallan a cabalidad todas sus ecuaciones fundamentales. Posteriormente se presentan algunas estructuras hexaportales muy utilizadas, se elige una y se analizan sus características. Se presentan algunas aplicaciones de las redes hexaportales y sus diversas aplicaciones actuales. Con base en el material investigado se confirma que la reflectometría es un área con gran potencial en múltiples aplicaciones actuales, incluyendo su aportación en la docencia de las microondas.

En un escenario de crisis permanente brota el SARS-CoV-2, generando una pandemia global sin precedentes la cual ha cobrado la vida de miles de personas y a su vez un fuerte impacto en las economías mundiales. En este contexto, se han profundizado los flujos informacionales y acelerado la adopción de formas de teletrabajo o trabajo a distancia debido a la necesidad de mantener operativas una parte importante de las empresas, industrias y servicios públicos, en medio de medidas de aislamiento social y múltiples cuarentenas que se han aplicado en distintas regiones del mundo y en Chile, más particularmente. En marzo de 2020, se promulga la ley Nº21.220 que modifica el Código del Trabajo en materia de trabajo a distancia, o como se le ha denominado, la ley de “teletrabajo”. Tal como lo indica su título, este artículo pretende exponer, desde una mirada descriptiva y reflexiva, los avances y riesgos de precarización para las trabajadoras y trabajadores en Chile que instala este nuevo cuerpo legal.

Despite the central role of microorganisms in soil fertility, little understanding exists regarding the impact of management practices and soil microbial diversity on soil processes. Strong correlations among soil microbial composition, management practices, and microbially mediated processes have been previously shown. However, limited integration of the different parameters has hindered our understanding of agroecosystem functioning. Multivariate analyses of these systems allow simultaneous evaluation of the parameters and can lead to hypotheses on the microbial groups involved in specific nutrient transformations. In the present study, using a multivariate approach, we investigated the effect of microbial composition (16SrDNA sequencing) and soil properties in carbon mineralization (CMIN) (BIOLOG™, Hayward, CA, USA) across different management categories on coffee agroecosystems in Mexico. Results showed that (i) changes in soil physicochemical variables were related to management, not to region, (ii) microbial composition was associated with changes in management intensity, (iii) specific bacterial groups were associated with different management categories, and (iv) there was a broader utilization range of carbon sources in non-managed plots. The identification of specific bacterial groups, management practices, and soil parameters, and their correlation with the utilization range of carbon sources, presents the possibility to experimentally test hypotheses on the interplay of all these components and further our understanding of agroecosystem functioning and sustainable management.

Astaxanthin (ASX) is a xanthophyll pigment considered as a nutraceutical with high antioxidant activity. Several clinical trials have shown the multiple health benefits of this molecule; therefore, it has various pharmaceutical industry applications. Commercial astaxanthin can be produced by chemical synthesis or through biosynthesis within different microorganisms. The molecule produced by the microorganisms is highly preferred due to its zero toxicity and superior therapeutic properties. However, the biotechnological production of the xanthophyll is not competitive against the chemical synthesis, since the downstream process may represent 70–80% of the process production cost. These operations denote then an opportunity to optimize the process and make this alternative more competitive. Since ASX is produced intracellularly by the microorganisms, high investment and high operational costs, like centrifugation and bead milling or high-pressure homogenization, are mainly used. In cell recovery, flocculation and flotation may represent low energy demanding techniques, whereas, after cell disruption, an efficient extraction technique is necessary to extract the highest percentage of ASX produced by the cell. Solvent extraction is the traditional method, but large-scale ASX production has adopted supercritical CO2 (SC-CO2), an efficient and environmentally friendly technology. On the other hand, assisted technologies are extensively reported since the cell disruption, and ASX extraction can be carried out in a single step. Because a high-purity product is required in pharmaceuticals and nutraceutical applications, the use of chromatography is necessary for the downstream process. Traditionally liquid-solid chromatography techniques are applied; however, the recent emergence of liquid-liquid chromatography like high-speed countercurrent chromatography (HSCCC) coupled with liquid-solid chromatography allows high productivity and purity up to 99% of ASX. Additionally, the use of SC-CO2, coupled with two-dimensional chromatography, is very promising. Finally, the purified ASX needs to be formulated to ensure its stability and bioavailability; thus, encapsulation is widely employed. In this review, we focus on the processes of cell recovery, cell disruption, drying, extraction, purification, and formulation of ASX mainly produced in Haematococcus pluvialis, Phaffia rhodozyma, and Paracoccus carotinifaciens. We discuss the current technologies that are being developed to make downstream operations more efficient and competitive in the biotechnological production process of this carotenoid.

A Proportional Integral Derivative (PID) controller is commonly used to carry out tasks like position tracking in the industrial robot manipulator controller; however, over time, the PID integral gain generates degradation within the controller, which then produces reduced stability and bandwidth. A proportional derivative (PD) controller has been proposed to deal with the increase in integral gain but is limited if gravity is not compensated for. In practice, the dynamic system non-linearities frequently are unknown or hard to obtain. Adaptive controllers are online schemes that are used to deal with systems that present non-linear and uncertainties dynamics. Adaptive controller use measured data of system trajectory in order to learn and compensate the uncertainties and external disturbances. However, these techniques can adopt more efficient learning methods in order to improve their performance. In this work, a nominal control law is used to achieve a sub-optimal performance, and a scheme based on a cascade neural network is implemented to act as a non-linear compensation whose task is to improve upon the performance of the nominal controller. The main contributions of this work are neural compensation based on a cascade neural networks and the function to update the weights of neural network used. The algorithm is implemented using radial basis function neural networks and a recompense function that leads longer traces for an identification problem. A two-degree-of-freedom robot manipulator is proposed to validate the proposed scheme and compare it with conventional PD control compensation.

Silos are used worldwide to store granular and powdered materials. Agricultural, food and feed products are commonly stored in silos. However, many questions remain unanswered about how to estimate the pressures applied by the bulk material, which are needed to design and calculate the structure of the silo. The complexity of the laws that govern the mechanical behavior of the stored material along with the low number of experimental stations in the world hinder progress in this field. The aim of this study was to elucidate the relationship of the hopper angle, flow pattern and vertical stress at the cylinder-to-hopper transition in slender silos. Therefore, a set of experiments was conducted on a test station to measure the vertical stress produced by maize at the cylinder-to-hopper transition. Five different hopper angles were used. The experiments comprised the filling, the static phase and the discharge. The results obtained show that the hopper angle influences the vertical stress at the cylinder-to-hopper transition. Some bottom configurations (flat bottom and bottom with an angle of 30°) led to vertical stresses that exceeded the value calculated according to Eurocode 1. It is clear that further experimental studies are still necessary to understand the underlying physical phenomena and the relations between pressures, silo geometry and flow pattern of the stored material.

Background: Allopurinol is a xanthine oxidase inhibitor used in the treatment of patients with gout. Approximately 2% of patients are affected by adverse reactions to this drug. Severity ranges from mild rashes to severe reactions in up to 0.4% of cases. De-sensitization is carried out by administering increasing doses of the drug. Case report: Thirty-year old man diagnosed with hypercholesterolemia and hypertriglyceridemia treated with bezafibrate and pravastatin, systemic arterial hypertension treated with losartan and a 10-year history of hyperuricemia with gout. Tophi were found in metacarpophalangeal joints and elbows. Treatment was started with allopurinol 300 mg/day. Two weeks later, he experienced facial erythema with itching and maculopapular lesions on the malar region 1 hour after the medication was ingested. An outpatient drug de-sensitization protocol was initiated, starting with 5 mg, and with gradual dose increases every 4 to 5 days for 59 days until the desired maintenance dose (300 mg) was reached. Conclusions: Experience shows that de-sensitization to allopurinol is a safe alternative when there is hypersensitivity and treatment with this drug is required.

Abstract Background Mammary cancer has a high incidence in canines and is an excellent model of spontaneous carcinogenesis. Molecular iodine (I2) exerts antineoplastic effects on different cancer cells activating re-differentiation pathways. In co-administration with anthracyclines, I2 impairs chemoresistance installation and prevents the severity of side effects generated by these antineoplastic drugs. This study is a random and double-blind protocol that analyzes the impact of I2 (10 mg/day) in two administration schemes of Doxorubicin (DOX; 30 mg/m2) in 27 canine patients with cancer of the mammary gland. The standard scheme (sDOX) includes four cycles of DOX administered intravenously for 20 min every 21 days, while the modified scheme (mDOX) consists of more frequent chemotherapy (four cycles every 15 days) with slow infusion (60 min). In both schemes, I2 or placebo (colored water) was supplemented daily throughout the treatment. Results mDOX attenuated the severity of adverse events (VCOG-CTCAE) in comparison with the sDOX group. The overall tumor response rate (RECIST criteria) for all dogs was 18% (interval of reduction 48–125%), and no significant difference was found between groups. I2 supplementation enhances the antineoplastic effect in mDOX, exhibiting a significant decrease in the tumor epithelial fraction, diminished expression of chemoresistance (MDR1 and Survivin) and invasion (uPA) markers and enhanced expression of the differentiation factor known as peroxisome proliferator-activated receptors type gamma (PPARγ). Significant tumor lymphocytic infiltration was also observed in both I2-supplemented groups. The ten-month survival analysis showed that the entire I2 supplementation (before and after surgery) induced 67–73% of disease-free survival, whereas supplementation in the last period (only after surgery) produced 50% in both schemes. Conclusions The mDOX+I2 scheme improves the therapeutic outcome, diminishes the invasive capacity, attenuates the adverse events and increases disease-free survival. These data led us to propose mDOX+I2 as an effective treatment for canine mammary cancer.

En este artículo se analiza la relación entre la inseguridad y el poder político en el Triángulo Norte de Centroamérica utilizando las teorías de la lógica del poder y de la acción colectiva. Básicamente se plantea que, después de la firma de los Acuerdos de Paz, los grupos de acción colectiva que controlaban la política y la economía de los Estados del Triángulo Norte vieron en la democracia un subproducto para extender su dominio extractivo, y que la racionalidad desde la que partieron ha ocasionado su antipatía hacia los grupos sociales más vulnerables ante el problema de la inseguridad.

Documenting the presence of bird species outside of its current distribution, allows us to understand their patterns of spatial and temporal distribution. In addition it allows us to assess their ecological value compared to other sites. The records presented here were observed between 2009 and 2018 on the coast of Jalisco and Colima. During this time, we made monthly or seasonal visits to coastal wetlands and islands in order to identify and count the waterbirds. As a result of this study we report the presence of eight bird species: Ross’s Goose (Anser rossii), Cavreri’s Murrelet (Synthliboramphus craveri), Cassin’s Auklet (Ptychoramphus aleuticus), Leach’s Storm-Petrel (Oceanodroma leucorhoa) and Juan Fernandez Petrel (Pterodroma externa). In addition, we registered for the first time the nesting of the Hermann’s Gull (Larus heermanni), the Great Blue Heron (Ardea herodias) and the Snail Kite (Rostrhamus sociabilis). Five of the species observed are considered in some category of protection in Mexico as well as considered “at risk” by the International Union for the Conservation of Nature. For some species, such as Cassin’s Auklet, Juan Fernández Petrel and the Leach’s Storm-Petrel, their presence was associated with the passage of tropical storms Linda (2009), Juliette (2013) and Marty (2009), respectively, which affected the Coast of the central Mexican Pacific. With the nesting record of the Hermann’s Gull, we increased the breeding range by 90 km, in addition to being the first report in Peña Blanca, Colima. The Great Blue Heron was recorded in all the years in which the Pajarera Island was visited, in the bay of Chamela, Jalisco. Nests for this species included three in 2015, six nests in 2016, and four in 2017. In the case of Snail Kite we only observed two nests in the Tule lagoon, Jalisco; one in both 2016 and 2017. These records increase the list of species of water birds and new nesting sites on the coast of Jalisco and Colima.

Resumen Actualmente las leyes ambientales son cada vez más rigurosas con los diagnósticos ambientales. Por lo anterior, es importante garantizar la confiabilidad de los resultados en los métodos de determinación de contaminantes. En el caso de los hidrocarburos, se usan métodos espectrofotométricos y cromatográficos, para los de fracción más pesada son empleadas técnicas gravimétricas Sin embargo, muchos trabajos discuten las diferencias en los resultados debido a las interacciones a matriz-contaminante. Con el fin de establecer herramientas básicas que permitan la adecuada determinación de los hidrocarburos presentes en suelo o agua, se llevó a cabo la determinación de hidrocarburos totales en distintos tipos de petróleo y destilados empleando un equipo Infracal TOG/TPH. Los diagramas de dispersión mostraron una tendencia logarítmica y se propuso un modelo de regresión lineal. Al analizar dicho modelo mediante el análisis Anova, resultó un p-valor menor a 2,2x10-16 y un coeficiente de determinación R=0,969, lo cual indica un ajuste satisfactorio del modelo potencia. Abstract Currently environmental laws are increasingly stringent with environmental diagnostics. Therefore, it is important ensure the reliability of results in the methods of determining contaminants. In the case of hydrocarbons, spectrophotometric and chromatographic methods are used, for heavier fraction are employed gravimetric techniques However, many papers discuss the differences in the results due to interactions matrix-pollutant. In order to establish basic tools that allow the proper determination of the hydrocarbons present in soil or water, was carried out the determination of total hydrocarbons in different types of oil and distillates using a computer Infracal TOG / TPH. Scatter plots and trend showed a logarithmic model linear regression was proposed. By analyzing the model by Anova analysis, it was a p-value less than 2,2x10-16 and a determination coefficient R = 0,969, indicating a satisfactory fit of the model output.

Weevils (Coleoptera: Curculionoidea) represent one of the most diverse groups of organisms on Earth; interactions with their host plants have been recognized to play a central role in their remarkable diversity, yet the exact mechanisms and factors still remain poorly understood. Using phylogenetic comparative analyses, here we investigate the evolution of host use and its possible role in diversification processes of Rhinusa and Gymnetron, two closely related groups of weevils that feed and develop inside plant tissues of hosts within the families Scrophulariaceae and Plantaginaceae. We found strong evidence for phylogenetic conservatism of host use at the plant family level, most likely due to substantial differences in the chemical composition of hosts, reducing the probability of shifts between host families. In contrast, the use of different plant organs represents a more labile ecological trait and ecological niche expansion that allows a finer partitioning of resources. Rhinusa and Gymnetron weevils initially specialized on plants within Scrophulariaceae and then shifted to the closely related Plantaginaceae; likewise, a gall inducing behavior evolved from non-galler weevils, possibly in response to resource competition, as galls facilitate larval development by providing enhanced nutrition and a favorable microhabitat. Results from trait-dependent diversification analyses suggest that both use of hosts within Plantaginaceae and parasitism on fruits and seed capsules are associated with enhanced diversification of Rhinusa and Gymnetron via low extinction rates. Our study provides quantitative evidence and insights on the ecological factors that can promote diversification in phytophagous insects that feed and develop inside plant tissues.

Este artículo analiza el diseño institucional de Quintana Roo y el cambio político ocurrido en dicho estado en las elecciones estatales del 2016. Se expone que más allá de las causas que llevaron al cambio democrático en el estado estas no resultan determinantes para consolidar el cambio político debido al diseño institucional de origen, que incluye una sociedad burocratizada y dependiente de los agentes del Gobierno. Se concluye que la sociedad de Quintana Roo se enfrenta a una dicotomía: por un lado, busca una mejora en las decisiones del Gobierno estatal, y por otro se resiste a cambiar el equilibrio institucional sobre el que se diseñó la estructura sociopolítica. El análisis se realiza con los aportes teóricos del nuevo institucionalismo y de la democracia subnacional. El trabajo se apoya en entrevistas abiertas a actores clave de la política local.

Gradient analysis was used to determine factors driving small-scale variation of cloud forest communities harboring Magnolia dealbata, a threatened species and bioculturally relevant tree for the Chinantecan, Mazatecan, Nahuan, and Zapotecan ethnicities in southern Mexico. Particularly, we aimed to: (a) determine factors explaining major community gradients at different heterogeneity scales along a small-scale elevational gradient, (b) test the Decreasing and the Continuum hypotheses along elevation, and (c) classify vegetation to assist in identifying conservation priorities. We used a stratified random sampling scheme for 21 woody stands along a small-scale (352 m) elevational transect. Four main data matrices were used (presence-absence, density, basal area, and guild data). Through Non-metric Multidimensional Scaling (NMS), Principal Coordinates Analysis (PCoA), and distance-based Redundancy Analysis (db-RDA), we found that major community variation was explained by soil pH, displaying an outstanding vegetation discontinuity, separating the species-rich relic Oreomunnea-Ticodendron-stands from stands with higher importance values for M. dealbata. The high species richness observed was explained by a combination of the windward effect of dry-seasonal maximum cloud condensation gain and habitat differentiation-specialization, a phenomenon that may also explain the mid-peak hypothesis and ensure the survival of relic species. Sampling-truncation and conservation status also played a role in this. Our results do not support the Decreasing and Continuum hypotheses along elevation.

Populus primaveralepensis A.Vázquez, Muñiz-Castro & Zuno sp. nov., a new species from relict gallery cloud forest in Bosque La Primavera Biosphere Reserve (Mexico), is described and illustrated. The new species belongs to P. subsect. Tomentosae Hart., and is morphologically similar to P. luziarum A.Vázquez, Muñiz-Castro & Padilla-Lepe, but differs from it in having taller trees without root suckers, white and ringed young stems and branches, a branching angle of ca 45º, leaves with higher blade to petiole ratio, leafs frequently elliptic or ovate to widely ovate (vs widely ovate to ovate-deltoid), denser inflorescences, and shorter capsules. The conservation status of the species was assessed as Critically Endangered (CR).

The professional secret (PS) is defined as the compulsory reserve professionals must have in front of the knowledge they achieve because of their work. Secret -in general- and professional secret -in particular-, are especially important for society. For this reason, their violation is considered as a criminal offense in most countries. In Colombia, the violation of professional secret is not a criminal offense, except the violation of industrial or commercial reserve. This is established in the Penal Code - Article 308 and Article 418-.

In this work, fifty yeast strains, isolated from the spontaneous alcoholic fermentation of Agave duranguensis to produce mezcal, were tested using the double coupling system. These yeasts were from the genera Pichia, Torulaspora, Saccharomyces, Kluyveromyces, Deckera, Hanseniaspora, and Candida. P. fermentans ITD00165 was the best isoamyl acetate producer, yielding 0.38 g/L of ester after incubation for 24 h, while K. marxianus ITD00211 produced 0.32 g/L of ester. Thus P. fermentans TD00165 could be considered as an excellent choice for use in optimization studies of the culture medium and bioreactor operating conditions to develop a process for biotechnological production of isoamyl acetate.

Se analiza la relevancia del tema del aprendizaje desde una mirada psicoeducativa. Se realiza un breve recorrido sobre el modo en que el aprendizaje ha sido estudiado por los psicólogos en el siglo anterior y lo que va del presente y se toma postura por una perspectiva constructivista-integracionista cognitiva y sociocultural. Se presentan los principios relevantes del tema de aprendizaje a los que se ha logrado acceder después de años de trabajo de teorización, in- vestigación y reflexión psicológica. También se abordan tres problemas impor- tantes en la actualidad para el tema del aprendizaje: el análisis del triángulo di- dáctico en la educación escolar, el problema de aprender a aprender y el papel que pueden desempeñar las tecnologías de la información y la comunicación (TIC) en el aprendizaje. Por último, se reconoce que el estudio más promisorio del aprendizaje en los próximos años se derivará del abordaje interdisciplinario dentro de contextos y escenarios educativos naturales.

The flavor violating leptonic decays of the $\tau$ and $\mu$ leptons into three lighter charged leptons are revisited in the framework the Standard Model with massive neutrinos. In contrast to the previous prediction, we have found strongly suppressed rates for the $\tau^-\to \mu^- \ell^+ \ell^-$ ($\ell=\mu, e$) decays. Our results are in good agreement with the approximation of neglecting masses and momenta of the external particles in the loop integrals made in the first computation for the $\mu^- \to e^-e^+ e^-$ decay.

Assessing the research of individual scholars is currently a matter of serious concern and worldwide debate. In order to gauge the long-term efficacy and efficiency of this practice, we carried out a limited survey of the operation and outcome of Mexico's 30-year old National System of Investigators or SNI, the country's main instrument for stimulating competitive research in science and technology. A statistical random sample of researchers listed in the area of Humanities and Behavioral Sciences-one of SNI's first and better consolidated academic divisions comprising a wide range of research disciplines, from philosophy to pedagogy to archaeology to experimental brain research-was screened comparing individual ranks or "Levels of distinction" to actual compliance with the SNI's own evaluation criteria, as reflected in major public databases of scholarly production. The same analysis was applied to members of a recent Review Committee, integrated by top-level researchers belonging to that general area of knowledge, who have been in charge of assessing and ranking their colleagues. Our results for both sets of scholars show wide disparity of individual productivity within the same SNI Level, according to all key indicators officially required (books issued by prestigious publishers, research articles appeared in indexed journals, and formation of new scientists), as well as in impact estimated by numbers of citations. Statistical calculation from the data indicates that 36% of members in the Review Committee and 53% of researchers in the random sample do not satisfy the official criteria requested for their appointed SNI Levels. The findings are discussed in terms of possible methodological errors in our study, of relevance for the SNI at large in relation to independent appraisals, of the cost-benefit balance of the organization as a research policy tool, and of possible alternatives for its thorough restructuring. As it currently stands SNI is not a model for efficient and effectual national systems of research assessment.

La industria del vestido es global, pues sus actividades de producción y comercialización se encuentran diseminadas en todos los países del planeta. Sin embargo, una forma de reducir los costos de producción ha sido trasladar el ensamble a los países con bajo costo de mano de obra como México, lo cual se ha traducido en precariedad y exclusión social en algunos casos, originando una alta rotación de personal en esta industria. Por su parte, la actividad de la confección en el Estado de Tlaxcala es una de las más importantes por el número de empleos que genera y el de empresas establecidas de manera formal, aunque existe también un porcentaje importante de la población en este Estado que se dedica de manera informal a la confección de prendas de vestir, bajo la modalidad de la maquila domiciliaria.

Algunas mediciones de radiación solar obtenidas en la ciudad de México indican que pueden producirse valores anormales varios días antes de un sismo fuerte. Las anomalías se presentan tanto en la parte verde como en la roja del espectro. Las emisiones parecen ser intermitentes y se traducen en una mayor varianza de la intensidad horaria medida en el actinómetro. Antes y después del sismo de Petatlán, .México del 14 de marzo de 1979 (M7.4), se observaron fuertes fluctuaciones en la luminosidad del cielo. En algunos casos la intensidad de la radiación excedió el valor esperado para una atmósfera transparente. Se propone que las observaciones altas se deben a una radiación en el espectro visible que se origina en la tierra, y que es reflejada por la capa de nubes y por la contaminación atmosférica. doi: https://doi.org/10.22201/igeof.00167169p.1996.35.4.532

El artículo presenta algunas reflexiones preliminares sobre la relación entre partidos políticos y calidad de la democracia, en el ámbito procedimental de la misma. Inicia con una síntesis del contexto de cambios que se han dado en el sistema de partidos en los últimos años, para pasar luego a plantear algunas debilidades que muestran los partidos políticos en el actual contexto histórico, tanto en su desempeño dentro del sistema político, como a nivel de sus dinámicas internas. El supuesto de fondo es que dichas debilidades afectan de alguna manera la calidad de la democracia, en la medida en que vulneran derechos básicos de la ciudadanía en el marco de la democracia representativa.

En este trabajo, se analiza la experiencia de los adolescentes nacidos en el extranjero de familias españolas, y más concretamente gallegas, emigrantes y que han llegado a España por sí mismos o con el retorno de sus progenitores, poniendo especial atención en su incorporación a la sociedad española, el contraste entre los sistemas de valores de nuestra sociedad y los suyos de procedencia, así como la asimilación, en su caso, de los valores y los hábitos familiares, dependiendo de que procedan de países iberoamericanos o europeos. Podemos destacar el idioma como signo de identidad y dividir las diferencias culturales en dos grandes grupos: los que encuentran una vida más segura, mejores infraestructuras, más abierta, pero menos humana, y los que perciben que hay más permisividad pero menos diferencias entre el país acogedor y el de origen. El primero proviene de países iberoamericanos y el segundo procede de países europeos.

Una de las consecuencias del envejecimiento en el ámbito laboral es la jubilación. Se trata de una nueva etapa de la vida para la que muchas personas no están adecuadamente preparadas y esa falta de preparación y, en su caso, adaptación, tiene repercusiones no deseadas ni deseables en la salud física y mental de los trabajadores y en su vida y relaciones sociales y familiares. De cuanto antecede y se aborda en este artículo, se deduce la conveniencia de enfrentarse a este proceso de una forma integral.

Este documento ofrece una entrevista realizada por los tres autores el 10 de junio de 2004 al Dr. César Coll Salvador de la Universidad de Barcelona, quien es uno de los psicólogos de la educación más reconocidos e influyentes en el ámbito hispanoamericano. En ella, Coll ofrece interesantes aportes acerca de temas como: el estatuto epistemológico de la psicología de la educación, las tendencias en la formación de los profesionales de este ámbito, las nuevas prácticas de la profesión, algunos problemas relacionados con la acumulación e inconmensurabilidad del conocimiento psicólogo y sobre la continuidad de los grupos académicos y de investigación.

Se determinaros las lesiones patológicas, así como los aislamientos bacteriológicos y micológicos de 140 muestras de pulmones provenientes de bovinos Holstein adultos, de los cuales 91 pertenecen a pulmones neumónicos y 49 pulmones normales. Posteriormente se realizó el análisis estadístico correspondiente, para determinar las correlaciones existentes entre los aislamientos presentes. La mayoría de las lesiones neumónicas (51%) estuvieron representadas por lesiones características de tuberculosis, seguido de neumonías exudativas (25%) en donde Pasteurella haemolytica fue el aislamiento más frecuente. Otras diversas lesiones fueron encontradas en los pulmones neumónicos, aunque en menor proporción, De los 49 pulmones normales, el 71% no mostraron crecimiento microbiano alguno; mientras que en el 29% restante se detectaron diversos aislamientos bacterianos y micóticos de microorganismos comúnmente presentes en el aparato respiratorio superior de los bovinos como son Pasteurella haemolytica, gérmenes piógenos, hongos como Aspergillus, etc.