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Abstract Depression is a severe mental health problem. Due to its relevance, the development of computational tools for its detection has attracted increasing attention in recent years. In this context, several research works have addressed the problem using word-based approaches (e.g., a bag of words). This type of representation has shown to be useful, indicating that words act as linguistic markers of depression. However, we believe that in addition to words, their contexts contain implicitly valuable information that could be inferred and exploited to enhance the detection of signs of depression. Specifically, we explore the use of user’s characteristics and the expressed sentiments in the messages as context insights. The main idea is that the words’ discriminative value depends on the characteristics of the person who is writing and on the polarity of the messages where they occur. Hence, this paper introduces a new approach based on specializing the framework of classification to profiles of users (e.g., males or women) and considering the sentiments expressed in the messages through a new text representation that captures their polarity (e.g., positive or negative). The proposed approach was evaluated on benchmark datasets from social media; the results achieved are encouraging, since they outperform those of state-of-the-art corresponding to computationally more expensive methods.

Background: Floristic inventories record the species observed in a particular region and serve as fundamental contributions to understanding biotic resources. Jalisco stands out as one of the Mexican states with significant floristic diversity. However, ongoing additions, documented through exploratory efforts, and periodic taxonomic revisions highlight the importance of maintaining an up-to-date inventory of vascular plants. Questions: What is the diversity, endemism and distribution of the vascular flora in Jalisco? Studied species: Tracheophytes. Study site and dates: Jalisco; September 2020 to February 2024. Methods: An updated list was compiled through a literature, review of herbarium specimens (IBUG) and electronic databases available online. Total richness was estimated for the state and for each municipality. Taxonomic diversity and species complementarity indexes between municipalities were estimated. Results: The vascular flora in Jalisco encompasses 242 families, 1,623 genera, and 7,110 species. Among these, there are 3,310 species endemics to Mexico, 412 species endemic to Jalisco, and 390 exotic species. The municipalities with the highest species diversity are Autlán de Navarro, Cuautitlán de García Barragán, and La Huerta. Conclusions: The vascular flora of Jalisco is the fourth richest in Mexico. The increasing numbers of diversity, endemism, and even introduced species emphasize the ongoing need to document the flora of Mexico.

Vehicular Ad Hoc Networks (VANETs) are considered by car manufacturers and the research community as the enabling technology to radically improve the safety, efficiency and comfort of everyday driving. However, before VANET technology can fulfill all its expected potential, several difficulties must be addressed. One key issue arising when working with VANETs is the complexity of the networking protocols compared to those used by traditional infrastructure networks. Therefore, proper design of the routing strategy becomes a main issue for the effective deployment of VANETs. In this paper, a reliable freestanding position-based routing algorithm (FPBR) for highway scenarios is proposed. For this scenario, several important issues such as the high mobility of vehicles and the propagation conditions may affect the performance of the routing strategy. These constraints have only been partially addressed in previous proposals. In contrast, the design approach used for developing FPBR considered the constraints imposed by a highway scenario and implements mechanisms to overcome them. FPBR performance is compared to one of the leading protocols for highway scenarios. Performance metrics show that FPBR yields similar results when considering freespace propagation conditions, and outperforms the leading protocol when considering a realistic highway path loss model.

Sequential Pattern Mining is a widely addressed problem in data mining, with applications such as analyzing Web usage, examining purchase behavior, and text mining, among others. Nevertheless, with the dramatic increase in data volume, the current approaches prove inefficient when dealing with large input datasets, a large number of different symbols and low minimum supports. In this paper, we propose a new sequential pattern mining algorithm, which follows a pattern-growth scheme to discover sequential patterns. Unlike most pattern growth algorithms, our approach does not build a data structure to represent the input dataset, but instead accesses the required sequences through pseudo-projection databases, achieving better runtime and reducing memory requirements. Our algorithm traverses the search space in a depth-first fashion and only preserves in memory a pattern node linkage and the pseudo-projections required for the branch being explored at the time. Experimental results show that our new approach, the Node Linkage Depth-First Traversal algorithm (NLDFT), has better performance and scalability in comparison with state of the art algorithms.

Uno de los problemas más serios dentro del análisis de la calidad de uniones soldadas es la localización e identificación de los defectos que se producen en la elaboración de dichas uniones. Como solución a este problema se propone la técnica de clasificación, por medio de la técnica de redes neuronales, para la localización e identificación en línea de defectos, tanto en piezas unidas por las técnicas convencionales (aporte de material-arco eléctrico) como por fricción, entre otras, mediante el uso de patrones de señales ultrasónicas. Las redes neuronales propuestas son: Kohonen y Perceptron por Multicapas, todo en un ambiente de instrumentación virtual. Actualmente, las técnicas más utilizadas en este campo son las basadas en el análisis radiológico (aplicación de rayos X) y en el análisis ultrasónico (aplicación de ondas ultrasónicas). El método de rayos X, además de ser peligroso al trabajar con radiación, requiere de personal, que además de su especialización tenga licencia del organismo oficial correspondiente,, por lo que su uso es restringido. El método de ultrasonido, a pesar de ser el que más se usa como ensayo no destructivo para la detección de defectos volumétricos, y sin contar con la limitación que supone el aspecto geométrico de la pieza, requiere también de personal con amplia experiencia en la interpretación de los ecogramas que, sin embargo, no necesita requisitos de autorización oficial, además de que su ejecución podría consumir mucho más tiempo que la alternativa de rayos X, lo que necesariamente encarece el ensayo. La técnica propuesta demuestra ser un método libre de riesgos personales, fiable, barata y sencilla de implantar para la solución de este importante problema.

Background: Endemism can originate from multiple biogeographic and evolutionary processes that promote the formation or persistence of species with restricted distributions (rare species). Understanding rare species’ distributions is a central question in biogeography and is crucial for biodiversity conservation. Questions: What are the rarest plant species in Mexico? How are they distributed? Under what risk categories should they be classified? Studied species: Vascular species considered rare in the flora of Mexico. Study site: Mexico. Methods: “Rare species” were defined as species endemic to Mexico whose distribution is restricted to a single 1 × 1° cell. We analyzed rare species’ distributions and proposed the risk category for each according to IUCN criteria. For some of the species distributed in the cell with the highest number of rare species, we compared the proposed category with published evaluations. Results: We identified 2,705 rare species. The richest cells in terms of rare species are in southern Mexico. Only 302 species had been previously evaluated under IUCN criteria. The remaining 2,403 qualify for the Near Threatened (NT) category or higher. The cell with the highest rare species richness, located in the Sierra Norte of Oaxaca, contained only 10 species with an existing IUCN risk category; for another 81 species, the categories of Vulnerable (VU), Endangered (EN) or Critically Endangered (CR) are indicated. Conclusions: Recognizing the rarity of these 2,705 species will increase attention on them, allowing more precise appraisal of their extinction risk and possible strategies for their conservation.

Antecedentes: Verbesina molinaria B.L. Rob. & Greenm. y V. oncophora B.L. Rob. & Seaton son especies con circunscripción conflictiva; algunos autores las consideran como especies distintas mientras que otros como una sola (V. oncophora). Preguntas: ¿Son dos especies de Verbesina? ¿Un análisis linear discriminante (LDA) ayudará a diferenciarlas? Especies de estudio/Modelo matemático: Verbesina molinaria y V. oncophora / Pruebas de Royston, Shapiro-Wilk, Levene, correlación (Pearson), factor de inflación de la varianza (VIF) y LDA. Sitio y años de estudio: México; 2022-2023. Métodos: Se revisaron tipos, protólogos, así como ejemplares de ambas especies depositados en ENCB, HUMO, MEXU y UAMIZ, asignándoles un nombre preliminar y elaborando una matriz de datos. Se generaron diagramas de cajas para evaluar diferencias entre los caracteres analizados; las pruebas estadísticas se realizaron utilizando el software Rstudio. Resultados: Los tipos y protólogos permitieron identificar diferencias morfológicas entre ellas. Las pruebas de Royston y Shapiro-Wilk respaldaron la normalidad entre los caracteres evaluados. La prueba de Levene sugiere que no hay diferencias significativas entre los caracteres; finalmente, la correlación de Pearson y el VIF indican ausencia de correlación o colinealidad. El análisis LDA mostró una precisión del 100 % en la asignación de los ejemplares con las asignaciones a priori. Conclusiones: Las diferencias morfológicas y las pruebas estadísticas, apoyan el reconocimiento de dos entidades distintas, V. oncophora con amplia distribución en el centro de México y V. molinaria con distribución más restringida, mejor conocida hasta la fecha en los estados de México, Michoacán y Morelos.

Antecedentes: Las hojas han sido utilizadas para definir secciones en el género Brickellia, lo que permite postular su valor taxonómico en grupos monofiléticos, así como identificar el grado de similitud morfológica entre especies y secciones en un contexto taxonómico y filogenético. Preguntas: ¿Las especies de Brickellia sección Barroetea se pueden diferenciar con las formas de las láminas foliares? ¿La sección se reconoce de las demás secciones del género con base en la forma foliar?, ¿las formas foliares son un rasgo conservado en el género Brickellia? Especies de estudio: Se utilizaron seis especies de la sección Barroetea y 19 especies de otras secciones de Brickellia y géneros relacionados (Ageratina y Carminatia). Métodos: Se realizó un análisis linear discriminante y un filomorfoespacio para conocer las diferencias y evaluar la conservación de la forma foliar. Resultados: Las especies de la sección Barroetea presentaron diferencias significativas a nivel específico, excepto en Brickellia sonorana. Las especies evaluadas de las secciones Barroetea, Brickellia, Coleosanthus, Leptanthodium y Xerobrickellia tienden a formas ovado-deltoideas, excepto Microphyllae donde son reniformes, en Phanerostylis ovadas o elípticas y en Gemmipedium y Kuhnia lineares. El filomorfoespacio muestra un traslape entre las secciones analizadas; las secciones ancestrales muestran un cambio morfológico mayor que las secciones de reciente diversificación y la conservación de la forma foliar no se confirmó estadísticamente. Conclusiones: La mayoría de las especies de Brickellia sección Barroetea se pueden diferenciar entre ellas, pero no de las demás secciones del género Brickellia. Las formas foliares no se conservan en las secciones del género.

Antecedentes: El noreste de México, estados de Coahuila, Nuevo León y Tamaulipas, constituye una región heterogénea que incluye sierras, planicies continentales y llanuras costeras con una infinidad de ambientes, substratos geológicos y gradientes altitudinales que favorecen la presencia de una rica biodiversidad. No existe una síntesis que documente la diversidad florística de esta región. Preguntas: ¿Cuál es la magnitud de la diversidad de plantas vasculares en el noreste de México?, ¿Cuáles son las familias y géneros con mayor número de especies?, ¿Cómo se distribuye geográficamente esta riqueza florística en toda la región y cuáles son sus elementos más característicos? Especies de estudio: 7,088 especies de plantas vasculares. Sitio de muestreo: estados de Coahuila, Nuevo León y Tamaulipas. Métodos: Se consultó literatura florística-taxonómica sobre la flora de la región y bases de datos de ejemplares para hacer un análisis espacial de la biodiversidad usando celdas de 1° de longitud y latitud. Se calculó la riqueza y el endemismo en la región, los estados y las celdas. Resultados: Para el noreste de México se reportan 7,088 especies de plantas vasculares, de las cuales 1,767 son endémicas de México. Conclusiones: El noreste de México registra una diversidad florística particularmente interesante y compleja, debido a que su territorio se ubica primordialmente fuera del neotrópico y porque constituye el límite boreal para muchos elementos de la flora de México.

Background: Knowledge of endemism in a region (natural or political) is fundamental to determining natural biogeographic regions and establishing conservation priorities. Questions: How many vascular plant species are endemic to the state of Puebla? What is the geographic distribution of endemism in the state? Are there centers of phylogenetic endemism? Studied species: 356 species of vascular plants. Study site: State of Puebla, Mexico. Methods: Based on the literature review and botanical specimens in digitized databases, the vascular plant species endemic or nearly endemic to the state of Puebla, Mexico, was assessed. Using a grid cell 1° × 1° latitude and longitude size, the incidence of each species was assessed. With the above information and a phylogeny of the species, a spatial phylogenetic analysis was carried out to detect centers of phylogenetic endemism. Results: 82.6 % of the 356 endemic species to Puebla are distributed in only one to three grid cells. The spatial phylogenetic analysis revealed centers of high phylogenetic diversity and endemism as well as delineated centers of mixed and paleo-endemism. Conclusions: The state of Puebla contains areas that meet the criteria to be considered centers of species endemism. Strategies toward a better understanding of plant endemism, as here proposed, suggest a better comprehension of the chorology of Mexican endemism, and assess the true role of our natural protected areas in conserving endemic species.

Background: Mesoamerica is one of the most important biodiversity hotspots on the planet. Despite significant efforts made over two centuries to contribute to the floristic knowledge of this region, our understanding of its flora is still scattered and uneven. Questions: What is the magnitude of the vascular plant species richness in the Usumacinta River Basin? Study site and dates: Usumacinta River Basin (Guatemala and Mexico), 1838-2018. Methods: We compiled the checklist by systematizing the floristic information acquired from various sources derived from numerous floristic and ecological studies. Results: We recorded 6,977 species, 1,892 genera and 274 families. The largest numbers of species (5,746) and records (58,859) correspond to the Mexican portion of the Usumacinta River Basin, compared to its Guatemalan counterpart (4,445 species and 19,952 records). The most species-rich families were Orchidaceae (598 species), Fabaceae (512), and Asteraceae (476). The prevalence of these and all other families with significant contributions to the flora varied among three elevation-defined sectors into which the Usumacinta River Basin was subdivided (lower, middle, and upper basin). Conclusions: The Usumacinta River Basin is a strategic region for plant biodiversity conservation as it hosts almost one third of all vascular plant species known for Mesoamerica and ca. 6 % of the entire flora in the Americas. Further botanical exploration should focus on those areas of the basin for which little or no information is available in order to gain a better appreciation of its flora.

Background: The 8th version of the "World Checklist of Vascular Plants" (WCVP) was recently published under the coordination of the Royal Botanic Gardens, Kew. It consists of a list of taxonomic names of species, genera, and families of vascular plants representing the most comprehensive and integrated list available today. Questions: How many accepted species does the WCVP include? Is the quality of the included information acceptable? How has the publication of worldwide species names evolved over time? Does the checklist include the species recorded for Mexico? Studied species: Worldwide species of vascular plants included in the WCVP. Study site: Worldwide and Mexico. Methods: A database was created based on the WCVP to answer the research questions. The number of genera and species by taxonomic status (accepted and synonyms) was quantified, some information quality tests were carried out, and the potential number of undiscovered species in the world was estimated using non-parametric techniques. Results: The WCVP contains 1,233,172 names, of which 418,737 are accepted. It is estimated that around 25 % more unknown species remain to be discovered in the world. The quality of the information contained in the WCVP is quite reliable and complete; only 3 % of Mexican species are not included in the WCVP. Conclusions: The WCVP synthesizes current taxonomic knowledge in an integrated manner and is useful for systematic and automated analyses. At the country level, at least for Mexico, it stands as an important reference source when attempting to understand and evaluate floristic knowledge.