122 research outputs found

    REGIONES PRIORITARIAS PARA LA CONSERVACIÓN DEL BOSQUE MESÓFILO DE MONTAÑA

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    Cloud forests (CFs) shelter an extraordinary biodiversity, play a key role in the regulation of water and nutrient cycles, and are the most threatened terrestrial ecosystems in México. Although all CFs are important, it is necessary to identify the areas where the actions directed at their sustainable management, conservation and restoration are more urgent. An initiative by the National Commission for the Knowledge and Use of Biodiversity is presented, to develop a diagnosis of the CFs in México in terms of their quality, main threats to their permanence and quality, as well as the opportunities present for their maintenance, recovery and social characteristics of their owners and users. Fifteen sub regions of critical priority were identified, 17 of high, nine of medium and four were pending due to the lack of information. The main recommendations to contribute to the conservation of this very valuable ecosystem are presented.Los bosques de niebla o bosques mesófilo de montaña (BMM) resguardan una biodiversidad extraordinaria, juegan un papel clave en la regulación de los ciclos hidrológicos y son los ecosistemas terrestres más amenazados en México. Si bien todos los BMM son importantes, es necesario identificar aquellas áreas donde las acciones encaminadas a su manejo sustentable, conservación y restauración son de carácter más urgente. Se presenta una iniciativa de la Comisión Nacional para el Conocimiento y Uso de la Biodiversidad para desarrollar un diagnóstico del BMM en México en términos de su calidad, las principales amenazas a su permanencia y a su calidad, así como las oportunidades existentes para su mantenimiento, recuperación y características sociales de sus propietarios y usuarios. Se identificaron 15 subregiones de prioridad crítica, 17 de alta, nueve de media y cuatro quedaron pendientes debido a la falta de información. Se presentan las principales recomendaciones para contribuir a la conservación de este ecosistema tan valioso

    Ischemic Preconditioning in Cardiac and Skeletal Muscle Induced by Exercise

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    Since it was discovered, ischemic preconditioning (IPC) has motivated research groups around the world to develop preconditioning protocols capable of protecting tissues against prolonged insults. In 31 years of study, promising results have been obtained on the beneficial role of the CPI and the mechanisms involved in its regulation. Also, different preconditioning protocols that have obtained results similar to the classic CPI have been developed, among which is the exercise-induced preconditioning (EP), that has been proven to protect the heart against an insult, mitigate the atrophy of the heart muscle and increase physical performance in athletes and/or athletes

    Lianas Suppress Seedling Growth and Survival of 14 Tree Species in a Panamanian Tropical Forest

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    Lianas are a common plant growth form in tropical forests, where they compete intensely with trees, decreasing tree recruitment, growth, and survival. If the detrimental effects of lianas vary significantly with tree species identity, as is often assumed, then lianas may influence tree species diversity and community composition. Furthermore, recent studies have shown that liana abundance and biomass are increasing relative to trees in neotropical forests, which will likely magnify the detrimental effects of lianas and may ultimately alter tree species diversity, relative abundances, and community composition. Few studies, however, have tested the responses of multiple tree species to the presence of lianas in robust, well‐replicated experiments. We tested the hypotheses that lianas reduce tree seedling growth and survival, and that the effect of lianas varies with tree species identity. We used a large‐scale liana removal experiment in Central Panama in which we planted 14 replicate seedlings of 14 different tree species that varied in shade tolerance in each of 16 80 × 80 m plots (eight liana‐removal and eight unmanipulated controls; 3136 total seedlings). Over a nearly two‐yr period, we found that tree seedlings survived 75% more, grew 300% taller, and had twice the aboveground biomass in liana‐removal plots than seedlings in control plots, consistent with strong competition between lianas and tree seedlings. There were no significant differences in the response of tree species to liana competition (i.e., there was no species by treatment interaction), indicating that lianas had a similar negative effect on all 14 tree species. Furthermore, the effect of lianas did not vary with tree species shade tolerance classification, suggesting that the liana effect was not solely based on light. Based on these findings, recently observed increases in liana abundance in neotropical forests will substantially reduce tree regeneration, but will not significantly alter tropical tree species diversity, relative abundance, or community composition

    Desarrollo psicocultural de niños mexicanos

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    En México habitan más de 30 millones de niños en contextos urbanos, rurales o indígenas, con niveles socieconómicos diferentes, que comparten múltiples aspectos de una historia milenaria que dio fruto a un país que es una rica mezcla de culturas, etnias y lenguas. Su situación solo se puede estudiar a partir de esta realidad multifacética. Este libro aspira a mejorar la comprensión de los diversos aspectos socioculturales que afectan el desarrollo psicológico y la vida de los niños mexicanos. Para ello, se presenta una panorámica de contextos y situaciones particulares que permiten identificar cómo en la niñez la historia individual o grupal tiene implicaciones relevantes en los aprendizajes, el comportamiento social y la evolución emocional y cognitiva. Asimismo, se brindan pistas para entender y atender mejor las necesidades de los niños en México, ya sea en el seno familiar, el ámbito escolar o a través de la implementación de políticas públicas efectivas.ITESO, A.C

    Wolbachia pipientis associated with tephritid fruit fly pests: from basic research to applications

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    Members of the true fruit flies (family Tephritidae) are among the most serious agricultural pests worldwide, whose control and management demands large and costly international efforts. The need for cost-effective and environmentally friendly integrated pest management (IPM) has led to the development and implementation of autocidal control strategies. These approaches include the widely used sterile insect technique and the incompatible insect technique (IIT). IIT relies on maternally transmitted bacteria (namely Wolbachia) to cause a conditional sterility in crosses between released mass-reared Wolbachia-infected males and wild females, which are either uninfected or infected with a different Wolbachia strain (i.e., cytoplasmic incompatibility; CI). Herein, we review the current state of knowledge on Wolbachia-tephritid interactions including infection prevalence in wild populations, phenotypic consequences, and their impact on life history traits. Numerous pest tephritid species are reported to harbor Wolbachia infections, with a subset exhibiting high prevalence. The phenotypic effects of Wolbachia have been assessed in very few tephritid species, due in part to the difficulty of manipulating Wolbachia infection (removal or transinfection). Based on recent methodological advances (high-throughput DNA sequencing) and breakthroughs concerning the mechanistic basis of CI, we suggest research avenues that could accelerate generation of necessary knowledge for the potential use of Wolbachia-based IIT in area-wide integrated pest management (AW-IPM) strategies for the population control of tephritid pests.Instituto de GenéticaFil: Mateos, Mariana. Texas A&M University. Departments of Ecology and Conservation Biology, and Wildlife and Fisheries Sciences; Estados UnidosFil: Martinez Montoya, Humberto. Universidad Autónoma de Tamaulipas. Unidad Académica Multidisciplinaria Reynosa Aztlan. Laboratorio de Genética y Genómica Comparativa; MéxicoFil: Lanzavecchia, Silvia Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Conte, Claudia Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Guillén, Karina. El Colegio de la Frontera Sur; MéxicoFil: Morán-Aceves, Brenda M. El Colegio de la Frontera Sur; MéxicoFil: Toledo, Jorge. El Colegio de la Frontera Sur; MéxicoFil: Liedo, Pablo. El Colegio de la Frontera Sur; MéxicoFil: Asimakis, Elias D. University of Patras. Department of Environmental Engineering; GreciaFil: Doudoumis, Vangelis. University of Patras. Department of Environmental Engineering; GreciaFil: Kyritsis, Georgios A. University of Thessaly. Department of Agriculture Crop Production and Rural Environment. Laboratory of Entomology and Agricultural Zoology; GreciaFil: Papadopoulos, Nikos T. University of Thessaly. Department of Agriculture Crop Production and Rural Environment. Laboratory of Entomology and Agricultural Zoology; GreciaFil: Augustinos, Antonios A. Hellenic Agricultural Organization. Institute of Industrial and Forage Crops. Department of Plant Protection; GreciaFil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tsiamis, George. University of Patras. Department of Environmental Engineering; Greci

    Lo tangible e intangible del diseño

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    1 archivo PDF (366 páginas)"El Departamento de Evaluación del Diseño, en el Tiempo de la División de Ciencias y Artes para el Diseño de la Universidad Autónoma Metropolitana, Azcapotzalco, publica este libro colectivo, donde se aborda la discusión y el análisis sobre "Lo tangible e intangible del diseño". Este libro tiene como finalidad el profundizar en distintas posiciones teóricas, metodológicas y empíricas, donde un grupo interdisciplinario de profesores investigadores del Departamento de Evaluación, desde la arquitectura, los estudios urbanos, la educación, la historia, la semiótica, el diseño de la comunicación gráfica y el industrial; buscan convergencias y discuten divergencias que puedan generar servir como referentes intelectuales y teóricos, en el diseño. Este libro es resultado del Cuarto Coloquio Departamental: Lo tangible e Intangible del Diseño. Evaluación de Objetos, Espacios, Mensajes, realizado durante el mes de septiembre del año 2004, el cual se constituyó como un espacio para el intercambio de experiencias académicas y profesionales, desde una perspectiva interdisciplinaria, centrada en la reflexión y la discusión sobre la manera de cómo se puede analizar, definir y evaluar, lo tangible y lo intangible en el diseño"

    Rights to Land, Forests and Carbon in REDD+ : Insights from Mexico, Brazil and Costa Rica

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    Land tenure and carbon rights constitute critical issues to take into account in achieving emission reductions, ensuring transparent benefit sharing and determining non-permanence (or non-compliance) liabilities in the context of REDD+ strategies and projects. This is so because tenure systems influence who becomes involved in efforts to avoid deforestation and improve forest management, and that land tenure, carbon rights and liabilities may be linked or divorced with implications for rural development. This paper explores these issues by looking at tenure regimes and carbon rights issues in Mexico, Brazil and Costa Rica. It is effectively shown that complex bundles of rights over forest resources have distinct implications for REDD+ design and implementation, and that REDD+ strategies in selected countries have to date failed in procedurally addressing land-use conflicts and carbon rights entitlements and liabilities

    The AMIGA project. I. Optical characterization of the CIG catalog

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    The AMIGA project (Analysis of the Interstellar Medium of Isolated Galaxies) is compiling a multiwavelength database of isolated galaxies that includes optical (B and Halpha), infrared (FIR and NIR) and radio (continuum plus HI and CO lines) properties. It involves a refinement of the pioneering Catalog of Isolated Galaxies. This paper is the first in a series and begins with analysis of the global properties of the nearly redshift-complete CIG with emphasis on the Optical Luminosity Function (OLF) which we compare with other recent estimates of the OLF for a variety of environments. The CIG redshift distribution for n= 956 galaxies re-enforces the evidence for a bimodal structure seen earlier in smaller samples. The peaks at redshift near 1500 and 6000km/s correspond respectively to galaxies in the local supercluster and those in more distant large-scale components (particularly Perseus-Pisces). The two peaks in the redshift distribution are superimposed on 50% or more of the sample that is distributed in a much more homogeneous way. The CIG probably represents the most homogeneous local field example that has ever been compiled. Our derivation of the CIG OLF is consistent with other studies of the OLF for lower density environments. This comparison via the Schechter parameter formalization shows that: 1) M* increases with galaxy surface density on the sky and 2) alpha shows a weaker tendency to do the same. The CIG represents the largest and most complete foundation for studies of isolated galaxies and is likely as close as we can come to a field sample. (Tables 1, 2 and 3 are available in electronic form at http://www.iaa.es/AMIGA.html).Comment: In press in A&

    Liana Impacts on Carbon Cycling, Storage and Sequestration in Tropical Forests

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    Mature tropical forests sequester large quantities of atmospheric CO2, which they store as plant biomass. These forests are changing however, including an increase in liana abundance and biomass over recent decades in Neotropical forests. We ask here how this increase in lianas might impact the tropical forest carbon cycle and their capacity for carbon storage and sequestration. Lianas reduce tree growth, survival, and leaf productivity; however, lianas also invest significantly in leaf production, and the increase in lianas could conceivably offset liana‐induced reductions in tree canopy productivity with no adverse effects to the forest‐level canopy productivity. By contrast, lianas decrease the total ecosystem uptake of carbon by reducing tree biomass productivity. Lianas themselves invest little in woody biomass, and store and sequester only a small proportion of the biomass in tropical forests. As lianas increase they may effectively displace trees, but the greater liana carbon stocks are unlikely to compensate for liana‐induced losses in net carbon sequestration and storage by trees. A potentially important additional consideration is the impact of lianas on the tree community. By competing more intensely with shade‐tolerant, more densely wooded trees than with fast‐growing, light‐wooded trees, lianas may shift tree composition toward faster‐growing species, which store relatively little carbon, and thereby further reduce the carbon storage capacity of tropical forests. Overall, current evidence indicates that the increase in lianas will negatively impact the carbon balance of tropical forests, with potentially far‐reaching consequences for global atmospheric CO2 levels and associated climate change
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