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Contrasting spatial patterns in active-fire and fire-suppressed mediterranean climate old-growth mixed conifer forests

Danny L. Fry  (2014, [Artículo])

In Mediterranean environments in western North America, historic fire regimes in frequent-fire conifer forests are highly variable both temporally and spatially. This complexity influenced forest structure and spatial patterns, but some of this diversity has been lost due to anthropogenic disruption of ecosystem processes, including fire. Information from reference forest sites can help management efforts to restore forests conditions that may be more resilient to future changes in disturbance regimes and climate. In this study, we characterize tree spatial patterns using four-ha stem maps from four old-growth, Jeffrey pine-mixed conifer forests, two with active-fire regimes in northwestern Mexico and two that experienced fire exclusion in the southern Sierra Nevada. Most of the trees were in patches, averaging six to 11 trees per patch at 0.007 to 0.014 ha-1, and occupied 27-46% of the study areas. Average canopy gap sizes (0.04 ha) covering 11-20% of the area were not significantly different among sites. The putative main effects of fire exclusion were higher densities of single trees in smaller size classes, larger proportion of trees (≥56%) in large patches (≥10 trees), and decreases in spatial complexity. While a homogenization of forest structure has been a typical result from fire exclusion, some similarities in patch, single tree, and gap attributes were maintained at these sites. These within-stand descriptions provide spatially relevant benchmarks from which to manage for structural heterogeneity in frequent-fire forest types.

article, climate, controlled study, ecosystem fire history, forest structure, geographic distribution, geographic mapping, land use, mathematical computing, mathematical model, Mexico, spatial analysis, taiga, United States, comparative study, conife CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Geospatial analysis of the distribution of empty spaces located in Nuevo Laredo, Tamaulipas

Claudio Curzio HECTOR DE LA TORRE GUTIERREZ (2021, [Artículo, Artículo])

Reflect about urban empty spaces means looking around all these lots that are distributed in different geographical points of the cities and are characterized because they are still waiting to be built, therefore, they are vacant, and also these spaces are empty in the sense of not provide any function. In this sense, the objective of this article is to present a methodological proposal specially designed to study this type of urban elements from the particular point of view of urban geography and spatial analysis. Specifically, through a series of surveys, both digital and physical, the various urban voids located in the city of Nuevo Laredo were recorded, thereby creating a database that included a total of 3,836 case studies. In this way, using different types of statistical techniques and spatial models, it was possible to obtain and interpret the results, managing to identify exactly what were the main patterns and characteristics of said geographic distribution.

empty spaces urban vacant lots geo-spatial analysis urban geography border in Nuevo Laredo Vacíos urbanos lotes baldíos análisis geo-espacial geografía urbana frontera en Nuevo Laredo Geografía urbana economía urbana morfología urbana CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Socio-spatial segregation of socio-environmental assets of public green spaces in the city of Durango, Mexico

Carlos Alejandro Custodio González Tania Ortiz Patricia Catalina Medina Pérez (2024, [Artículo, Artículo])

The current development model's accumulation logic has resulted in the emergence and consolidation of social processes like segregation, leading to differentiated access and availability of urban goods and services among social groups based on socioeconomic, ethnic, or societal standing. The current development model's accumulation logic has resulted in the emergence and consolidation of social processes like segregation, leading to differentiated access and availability of urban goods and services among social groups based on socioeconomic, ethnic, or societal standing. This disparity impacts employment levels, educational performance, urban decay, and environmental degradation. In this context, the article aims to examine the socio-spatial segregation in the access to socio-environmental amenities provided by public green spaces (EVP) in a medium-sized city, specifically Durango, Mexico. The analysis utilizes spatial analysis and statistical methods that involve five variables associated with EVPs: surface area, percentage, number, density, and the socioeconomic level of the population. A spatial pattern of segregation was identified through these variables, resulting in four clusters that impact how the city of Durango is inhabited, produced, reproduced, lived, and constructed.

sociospatial exclusion public space spatial autocorrelation spatial patterns spatial justice exclusión socioespacial espacio público autocorrelación espacial patrones espaciales justicia espacial CIENCIAS SOCIALES CIENCIAS SOCIALES

The past, the present, the future, and occupational self-efficacy: an attributions and cultural differences perspective

Daniel Arturo Cernas Ortiz (2023, [Artículo, Artículo])

This study´s objective was to examine empirical relationships between three dimensions of time perspective (future, present fatalistic, and past negative) and occupational self-efficacy. By surveying Mexican (n = 286) and U.S. (n = 272) respondents, we also tested the moderating role of culture. Regression analyses revealed that time perspective dimensions have significant associations with occupational self-efficacy, being future time perspective more potent than its past negative and present fatalistic counterparts. Moderation analyses indicated that none of the examined time perspective-self-efficacy relationships varied significantly between the U.S. and Mexico. Overall, this study suggests that relationships between time perspective and occupational self-efficacy vary according to different temporal dimensions, that future TP is key to develop occupational self-efficacy, and that cultural values may not exert a significant influence on the time perspective-occupational self-efficacy connection.

Perspectiva de tiempo autoeficacia diferencias culturales análisis de moderación CIENCIAS SOCIALES CIENCIAS SOCIALES Time perspective self-efficacy cultural differences moderation analysis

Structural analysis evaluationfor rollers of chassis dynoUsing finite element software

Jesús Emmanuel López Rizo ALFREDO CHAVEZ LUNA JAIME GONZALO SANTANA ESQUIVEL (2023, [Artículo])

This paper discusses the design considerations for a chassis dynamometer, focused on the rollers system used for measuring the power and torque of a vehicle in a university-level workshop. The design must prioritize factors such as safety, ease of use, adaptability to diverse types of vehicles, and the inclusion of safety systems to protect students and the vehicle. The work suggests adaptative features for the design, such as an adjustable fastening system and a compact and portable design, to adapt the structure into a university laboratory. The study also describes common methods for measuring engine power and torque using a chassis dynamometer, and the accurate and reliable measurement systems used for this purpose. This concludes with a discussion of the manufacturing methods used for the chassis dynamometer and a static analysis of the maximum effort capacity in each roller using Von Mises and Goodman fatigue theories. Developing a chassis dynamometer, in accordance the current patents available for workshop practices in a university is essential for providing students with comprehensive training.

Chassis dynamometer Conceptual design Finite element software Power and torque measurement Structural analysis INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Pertinencia del análisis transdisciplinario de la lírica-musical popular latinoamericana

Fermin Monroy Villanueva (2023, [Capítulo de libro])

Capítulo número 3 de la Sección El juego de los signos.

El objetivo de este texto es resaltar la importancia de llevar a la práctica el análisis transdisciplinario de lo que comúnmente es conocido como canción popular, elemento fundamental de los géneros musicales latinoamericanos que aún son considerados representativos de la identidad de sus países. De entre el basto universo integrado por este tipo de producciones, el enfoque está en la música de mariachi mexicano –base de la canción ranchera–, el tango canción argentino y el pasillo ecuatoriano. En este sentido, sostenemos que el análisis de las letras es una vía de aproximación para conocer las condiciones contextuales que caracterizaron la época en que fueron escritas, es decir, al ámbito social, cultural, político, histórico, económico y, de forma muy particular, al emocional. De tal modo, el análisis de la lírica permite reconocer continuidades y resaltar la vigencia de elementos simbólicos que participan en la configuración de sujetos, sociedades y culturas: patrióticos (en la mención de héroes nacionales, lugares y fechas históricas, banderas, escudos, himnos), religiosos (Dios, santos, vírgenes, mártires), espaciales (pueblos, barrios, el campo, las ciudades), conductuales (comportamientos estereotipados en mujeres y hombres, costumbres), etcétera.

Music--Semiotics. Popular music--Latin America--History and criticism. Musical analysis. Intercultural communication. Música popular. Análisis musical. Comunicación intercultural. Semiótica y arte. ML3845 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA DE LAS BELLAS ARTES MÚSICA, MUSICOLOGÍA

Vida de un muerto. Entre nuestro universo y el otro

Nicolás Amoroso Boelcke (2023, [Capítulo de libro])

Capítulo número 3 de la Sección Imágenes y representaciones.

Se analiza el film Raymond & Ray, desde la construcción de la vida de Harris, personaje muerto desde el principio del film, y esto se hace mediante las palabras, no con escenas de la infancia que mencionan Raymond y Ray ni tampoco en las acciones que participa con los otros perso¬najes que hablan de él. Harris habita el filme desde las palabras.

Semiotics and motion pictures. Culture--Semiotic models. Dialogue analysis. Semiótica y cine. Análisis del diálogo. NX180.S46 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA DE LAS BELLAS ARTES CINEMATOGRAFÍA