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145 resultados encontrados para: AUTOR: Díaz, Juan
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1.
Libro
Análisis edafoambiental para el desarrollo sostenible de áreas rurales / Javier Almorox Alonso, Chinquinquirá Hontoria Fernández, Juan Gallardo Díaz
Almorox Alonso, Javier ; Hontoria Fernández, Chiquinquirá (coaut.) ; Gallardo Díaz, Juan (coaut.) ;
Madrid, España : Universidad Politécnica de Madrid, Escuela Técnica Superior de Ingenieros Agrónomos , s.f.
Clasificación: F/631.41 / A4
Bibliotecas: Campeche
Cerrar
SIBE Campeche
ECO040003274 (Disponible)
Disponibles para prestamo: 1

2.
Libro
Investigación para el desarrollo regional sur: Chiapas, Guerrero y Oaxaca
Toledo Flores, Javier (editor) ;
Distrito Federal, México : Consejo Nacional de Ciencia y Tecnología :: Sistema de Investigación Benito Juárez , s.f.
Clasificación: CH/307.12097275 / I5
Bibliotecas: San Cristóbal , Tapachula
Cerrar
SIBE San Cristóbal
ECO010012034 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Tapachula
ECO020012039 (Disponible) , ECO020012038 (Disponible)
Disponibles para prestamo: 2

PDF
Resumen en: Español | Inglés |
Resumen en español

El objetivo del estudio fue determinar el valor nutritivo, la fermentación ruminal y la producción de metano in vitro del follaje de especies arbóreas y arbustivas con potencial forrajero como estrategias de alimentación en época de secas y mitigación de las emisiones de metano. El líquido ruminal fue extraído por medio de una sonda esofágica. Se utilizó un diseño en bloques repetidos en el tiempo. El contenido de proteína cruda (PC) y fibra detergente neutro y acida fluctuaron de 6.14% a 21.78%, 44.34% a 77.43% y 16.12% a 49.53% de materia seca (MS). No se encontró diferencia en el volumen máximo de gas (p > 0.05). La degradabilidad fue diferente, observando la mejor en Tithonia diversifolia (760.40 g/kg de MS), Morus alba (800.66 g/kg de MS) y Hibiscus rosa-sinensis (800.16 g/kg de MS), mientras que la más baja fue Megatryrsus maximus (390.40 g/kg de MS y 287.40 g/kg de materia orgánica (MO)) (p < 0.05). No se observó diferencia en la producción de metano (CH4) (p > 0.05). Se concluye que L. leucocephala, P. piscipula, B. alicastrum y G. ulmifolia, T. diversifolia y M. alba tienen un alto potencial para ser incluidos en la dieta de rumiantes como fuentes de proteína en época de secas y estrategias para mitigar las emisiones de metano.

Resumen en inglés

The objective of the study was to determine the nutritional value, ruminal fermentation, and in vitro methane production of foliage of tree and shrubs species with forage potential as feeding strategies in dry season and mitigation of methane emissions. The rumen liquor was taken by an esophageal tube. A repeated block design overtime was used. The content of crude protein (CP) and neutral and acid detergent fiber ranged from 6.14% to 21.78%, 44.34% to 77.43% and 16.12% to 49.53% of dry matter (DM). No difference was found in the maximum volume of gas (p > 0.05). The degradability was different among species, and it was higher for Tithonia diversifolia (760.40 g/kg DM), Morus alba (800.66 g/kg DM) and Hibuscus rosa-sinensis (800.16 g/kg DM), whilst the lower was for Megathyrsus maximus (390.40 g/kg DM and 287.40 g/kg organic matter (OM)) (p < 0.05). No difference in methane (CH4) production was observed (p > 0.05). It is concluded that L. leucocephala, P. piscipula, B. alicastrum and G. ulmifolia, T. diversifolia, and M. alba have a high potential to be included in the ruminant diet as sources of protein in the dry season and strategies to mitigate methane emissions


Resumen en: Inglés |
Resumen en inglés

Species distribution models (SDMs) are statistical tools used to develop continuous predictions of species occurrence. ‘Integrated SDMs’ (ISDMs) are an elaboration of this approach with potential advantages that allow for the dual use of opportunistically collected presence-only data and site-occupancy data from planned surveys. These models also account for survey bias and imperfect detection through the use of a hierarchical modelling framework that separately estimates the species–environment response and detection process. This is particularly helpful for conservation applications and predictions for rare species, where data are often limited and prediction errors may have significant management consequences. Despite this potential importance, ISDMs remain largely untested under a variety of scenarios. We performed an exploration of key modelling decisions and assumptions on an ISDM using the endangered Baird’s tapir (Tapirus bairdii) as a test species. We found that site area had the strongest effect on the magnitude of population estimates and underlying intensity surface and was driven by estimates of model intercepts. Selecting a site area that accounted for the individual movements of the species within an average home range led to population estimates that coincided with expert estimates. ISDMs that do not account for the individual movements of species will likely lead to less accurate estimates of species intensity (number of individuals per unit area) and thus overall population estimates.

This bias could be severe and highly detrimental to conservation actions if uninformed ISDMs are used to estimate global populations of threatened and data-deficient species, particularly those that lack natural history and movement information. However, the ISDM was consistently the most accurate model compared to other approaches, which demonstrates the importance of this new modelling framework and the ability to combine opportunistic data with systematic survey data. Thus, we recommend researchers use ISDMs with conservative movement information when estimating population sizes of rare and data-deficient species. ISDMs could be improved by using a similar parameterization to spatial capture–recapture models that explicitly incorporate animal movement as a model parameter, which would further remove the need for spatial subsampling prior to implementation.


5.
Artículo
PDF
Resumen en: Inglés |
Resumen en inglés

Background: Ticks are a problem for cattle production mainly in tropical and subtropical regions, because they generate great economic losses. Acaricides and vaccines have been used to try to keep tick populations under control. This has been proven difficult given the resistance to acaricides and vaccines observed in ticks. Resistance to protein rBm86-based vaccines has been associated with the genetic diversity of Bm86 among the ectoparasite’spopulations. So far, neither genetic diversity, nor spatial distribution of circulating Bm86 haplotypes, have been studied within the Mexican territory. Here, we explored the genetic diversity of 125 Bm86 cDNA gene sequences from R. microplusfrom 10 endemic areas of Mexico by analyzing haplotype distribution patterns to help in understanding the population genetic structure of Mexican ticks. Results: Our results showed an average nucleotide identity among the Mexican isolates of 98.3%, ranging from 91.1 to 100%. Divergence between the Mexican and Yeerongpilly (the Bm86 reference vaccine antigen) sequences ranged from 3.1 to 7.4%. Based on the geographic distribution of Bm86 haplotypes in Mexico, our results suggest gene flow occurrence within different regions of the Mexican territory, and even the USA. Conclusions: The polymorphism of Bm86 found in the populations included in this study, could account for thepoor efficacy of the current Bm86 antigen based commercial vaccine in many regions of Mexico. Our data may contribute towards designing new, highly-specific, Bm86 antigen vaccine candidates against R. microplus circulatingin Mexico.


6.
- Artículo con arbitraje
*Solicítelo con su bibliotecario/a
Global distribution of earthworm diversity
Phillips, Helen R. P. (autora) ; Guerra, Carlos A. (autor) ; Bartz, Marie L. C. (coaut.) ; Briones, Maria J. I. (autora) ; Brown, George (autor) ; Crowther, Thomas W. (autor) ; Ferlian, Olga (autora) ; Gongalsky, Konstantin B. (autor) ; van den Hoogen, Johan (autor) ; Krebs, Julia (autora) ; Orgiazzi, Alberto (autor) ; Routh, Devin (autor) ; Schwarz, Benjamin (autor) ; Bach, Elizabeth M. (autora) ; Bennett, Joanne (coaut.) ; Brose, Ulrich (coaut.) ; Decaëns, Thibaud (coaut.) ; König Ries, Birgitta (coaut.) ; Loreau, Michel (autor) ; Mathieu, Jérôme (coaut.) ; Mulder, Christian (coaut.) ; van der Putten, Wim H. (coaut.) ; Ramirez, Kelly S. (coaut.) ; Rillig, Matthias C. (autor) ; Russell, David (autor) ; Rutgers, Michiel (autor) ; Thakur, Madhav P. (coaut.) ; de Vries, Franciska T. (autora) ; Wall, Diana H. (autora) ; Wardle, David A. (autor) ; Arai, Miwa (coaut.) ; Ayuke, Fredrick O. (autor) ; Baker, Geoff H. (coaut.) ; Beauséjour, Robin (autor) ; Bedano, José C. (autor) ; Birkhofer, Klaus (coaut.) ; Blanchart, Eric (autor) ; Blossey, Bernd (autor) ; Bolger, Thomas (autor) ; Bradley, Robert L. (autor) ; Callaham, Mac A. (coaut.) ; Capowiez, Yvan (coaut.) ; Caulfield, Mark E. (coaut.) ; Choi, Amy (coaut.) ; Crotty, Felicity V. (coaut.) ; Dávalos, Andrea (coaut.) ; Díaz Cosin, Darío J. (autor) ; Domínguez, Anahí (autora) ; Duhour, Andrés Esteban (autor) ; van Eekeren, Nick (coaut.) ; Emmerling, Christoph (coaut.) ; Falco, Liliana B. (autora) ; Fernández, Rosa (autora) ; Fonte, Steven J. (coaut.) ; Fragoso González, Carlos Enrique (autor) ; Franco, André L. C. (coaut.) ; Fugère, Martine (coaut.) ; Fusilero, Abegail T. (coaut.) ; Gholami, Shaieste (coaut.) ; Gundale, Michael J. (autor) ; Gutiérrez López, Mónica (autora) ; Hackenberger, Davorka K. (coaut.) ; Hernández, Luis M. (autor) ; Hishi, Takuo (coaut.) ; Holdsworth, Andrew R. (coaut.) ; Holmstrup, Martin (autor) ; Hopfensperger, Kristine (autora) ; Huerta Lwanga, Esperanza (autora) ; Huhta, Veikko (coaut.) ; Hurisso, Tunsisa T. (coaut.) ; Iannone III, Basil V. (coaut.) ; Iordache, Madalina (autora) ; Joschko, Monika (autora) ; Kaneko, Nobuhiro (coaut.) ; Kanianska, Radoslava (coaut.) ; Keith, Aidan M. (coaut.) ; Kelly, Courtland A. (coaut.) ; Kernecker, Maria L. (coaut.) ; Klaminder, Jonatan (autor) ; Koné, Armand W. (autor) ; Kooch, Yahya (coaut.) ; Kukkonen, Sanna T. (coaut.) ; Lalthanzara, H. (coaut.) ; Lammel, Daniel R. (autor) ; Lebedev, Iurii M. (coaut.) ; Li, Yiqing (coaut.) ; Lidon, Juan B. Jesús (autor) ; Lincoln, Noa K. (coaut.) ; Loss, Scott R. (coaut.) ; Marichal, Raphael (autor) ; Matula, Radim (coaut.) ; Moos, Jan Hendrik (autor) ; Moreno, Gerardo (autor) ; Morón Ríos, Alejandro (autor) (1960-) ; Muys, Bart (coaut.) ; Neirynck, Johan (autor) ; Norgrove, Lindsey (coaut.) ; Novo, Marta (autora) ; Nuutinen, Visa (coaut.) ; Nuzzo, Victoria (autora) ; Mujeeb Rahman P. (coaut.) ; Pansu, Johan (autor) ; Paudel, Shishi (coaut.) ; Pérès, Guénola (coaut.) ; Pérez Camacho, Lorenzo (autor) ; Piñeiro, Raúl (autor) ; Ponge, Jean François (autor) ; Rashid, Muhammad Imtiaz (coaut.) ; Rebollo, Salvador (autor) ; Rodeiro Iglesias, Javier (autor) ; Rodríguez, Miguel Ángel (autor) ; Roth, Alexander M. (autor) ; Rousseau, Guillaume X. (coaut.) ; Rozen, Anna (autora) ; Sayad, Ehsa (autora) ; van Schaik, Loes (coaut.) ; Scharenbroch, Bryant C. (coaut.) ; Schirrmann, Michael (autor) ; Schmid, Olaf (coaut.) ; Schröder, Boris (coaut.) ; Seeber, Julia (autora) ; Shashkov, Maxim P. (coaut.) ; Singh, Jaswinder (coaut.) ; Smith, Sandy M. (coaut.) ; Steinwandter, Michael (autor) ; Talavera, José A. (autor) ; Trigo, Dolores (autora) ; Tsukamoto, Jiro (coaut.) ; de Valença, Anne W. (coaut.) ; Vanek, Steven J. (coaut.) ; Virto, Iñigo (autor) ; Wackett, Adrian A. (autor) ; Warren, Matthew W. (coaut.) ; Wehr, Nathaniel H. (coaut.) ; Whalen, Joann K. (coaut.) ; Wironen, Michael B. (coaut.) ; Wolters, Volkmar (coaut.) ; Zenkova, Irina V. (autora) ; Zhang, Weixin (coaut.) ; Cameron, Erin K. (autor) ; Eisenhauer, Nico (autor) ;
Disponible en línea
Contenido en: Science Vol. 366, no. 6464 (October 2019), p. 480–485 ISSN: 1095-9203
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide.


7.
Libro
PDF
Índice

I Prólogo
II Introducción
III Reserva de la Biósfera El Triunfo
IV Historia previa a la creación de la Reserva de la Biósfera El Triunfo
V Esbozo de la historia de la Reserva de la Biósfera El Triunfo hasta 2018
Parte I
VI Análisis del conocimiento por grupos taxonómicos
Hongos
Estado actual del conocimiento de los hongos macroscópicos de la Reserva de la Biósfera El Triunfo
Comunidades vegetales
Árboles de la Reserva de la Biósfera El Triunfo
Palmas nativas
Estado actual del conocimiento de plantas epífitas en la Reserva de la Biósfera El Triunfo, Chiapas
Fauna invertebrados
Estudio de los arácnidos de la Reserva de la Biósfera El Triunfo
Coleópteros Melolonthidae y Cetoniidae en El Triunfo, Chiapas, México
Fauna vertebrados
Anfibios y reptiles de la Reserva de la Biósfera El Triunfo, Chiapas, México: estudios y recomendaciones para su conservación y manejo
Diversidad de aves en la Reserva de la Biósfera El Triunfo, Chiapas, México
El pavón, Oreophasis derbianus: estado del conocimiento y perspectivas de investigación y conservación en la Reserva de la Biósfera El Triunfo, Chiapas
Distribución de las aves rapaces diurnas en la Reserva de la Biósfera El Triunfo
Distribución y diversidad de colibríes en la Reserva de la Biósfera El Triunfo
Mamíferos de la Reserva de la Biósfera El Triunfo
Estado de conocimiento actual y prioridades de estudio del tapir centroamericano y felinos silvestres en la Reserva de la Biósfera El Triunfo, Chiapas
Amenazas
Amenazas a la biodiversidad de la Reserva de la Biósfera El Triunfo
Manejo de Recursos
Sustentabilidad en la Reserva de la Biósfera El Triunfo (REBITRI) ¿De qué estamos hablando?
Restauración y conservación de Orchidaceae en la Reserva de la Biósfera El Triunfo y el sureste de México
Especies prioritarias y propiedad de la tierra en El Triunfo

De la colonización y la deforestación a la conservación biológica en la Reserva de la Biósfera El Triunfo
Parte II
VII Análisis del estado de conocimiento de la Reserva de la Biósfera El Triunfo
VIII Apéndice


8.
Artículo
PDF
Resumen en: Inglés |
Resumen en inglés

Livestock production is a main source of anthropogenic greenhouse gases (GHG). The main gases are CHч with a global warming potential (GWP) 25 times and nitrous oxide (N2O) with a GWP 298 times, that of carbon dioxide (CO2) arising from enteric fermentation or from manure management, respectively. In fact, CHч is the second most important GHG emitted globally. This current scenario has increased the concerns about global warming and encouraged the development of intensive research on different natural compounds to be used as feed additives in ruminant rations and modify the rumen ecosystem, fermentation pattern, and mitigate enteric CHч. The compounds most studied are the secondary metabolites of plants, which include a vast array of chemical substances like polyphenols and saponins that are present in plant tissues of different species, but the results are not consistent, and the extraction cost has constrained their utilization in practical animal feeding. Other new compounds of interest include polysaccharide biopolymers such as chitosan, mainly obtained as a marine co-product. As with other compounds, the effect of chitosan on the rumen microbial population depends on the source, purity, dose, process of extraction, and storage. In addition, it is important to identify compounds without adverse effects on rumen fermentation. The present review is aimed at providing information about chitosan for dietary manipulation to be considered for future studies to mitigate enteric methane and reduce the environmental impact of GHGs arising from livestock production systems. Chitosan is a promising agent with methane mitigating effects, but further research is required with in vivo models to establish effective daily doses without any detrimental effect to the animal and consider its addition in practical rations as well as the economic cost of methane mitigation.


Resumen en: Inglés |
Resumen en inglés

The efforts for the development and testing of vaccines against Trypanosoma cruzi infection have increased during the past years. We have designed a TcVac series of vaccines composed of T. cruzi derived, GPI-anchored membrane antigens. The TcVac vaccines have been shown to elicit humoral and cellular mediated immune responses and provide significant (but not complete) control of experimental infection in mice and dogs. Herein, we aimed to test two immunization protocols for the delivery of DNA-prime/ DNA-boost vaccine (TcVac1) composed of TcG2 and TcG4 antigens in a BALB/c mouse model. Mice were immunized with TcVac1 through intradermal/electroporation (IDE) or intramuscular (IM) routes, challenged with T. cruzi, and evaluated during acute phase of infection. The humoral immune response was evaluated through the assessment of anti-TcG2 and anti-TcG4 IgG subtypes by using an ELISA. Cellular immune response was assessed through a lymphocyte proliferation assay. Finally, clinical and morphopathological aspects were evaluated for all experimental animals. Our results demonstrated that when comparing TcVac1 IDE delivery vs IM delivery, the former induced significantly higher level of antigen-specific antibody response (IgG2a + IgG2b > IgG1) and lymphocyte proliferation, which expanded in response to challenge infection. Histological evaluation after challenge infection showed infiltration of inflammatory cells (macrophages and lymphocytes) in the heart and skeletal tissue of all infected mice. However, the largest increase in inflammatory infiltrate was observed in TcVac1_IDE/Tc mice when compared with TcVac1_IM/Tc or non-vaccinated/infected mice. The extent of tissue inflammatory infiltrate was directly associated with the control of tissue amastigote nests in vaccinated/ infected (vs. non-vaccinated/infected) mice.

Our results suggest that IDE delivery improves the protective efficacy of TcVac1 vaccine against T. cruzi infection in mice when compared with IM delivery of the vaccine.


10.
Artículo
PDF PDF
Resumen en: Español | Inglés |
Resumen en español

En el sector rural de México se han identificado grupos de trabajo que se asocian en torno a un objetivo común, por ejemplo, para gestionar subsidios y capacitación; sin embargo, no se han estudiado a detalle los mecanismos que estos grupos utilizan para trabajar y enfrentar situaciones de cambio y vulnerabilidad. Este estudio tuvo como objetivo analizar el modelo de trabajo del Club de Labranza de Conservación, un grupo de productores ubicado en la región Frailesca de Chiapas, México. Con base en herramientas cualitativas, se analizaron la influencia de las políticas públicas, las relaciones de intercambio de conocimiento, así como el papel que juegan los valores y normas no establecidas en el desempeño del grupo. Los resultados indican que el intercambio de conocimiento, tanto al interior como al exterior del grupo, es importante para obtener mejores resultados productivos; adicionalmente se requiere contar con mecanismos de coordinación efectivos relacionados con la toma de decisiones en forma compartida, poseer experiencia y capacidad para gestionar y aplicar nuevas prácticas, tener un líder que promueva la cohesión y coordinación, así como promover el uso de mecanismos sociales (normas, valores, sanciones colectivas) que den legitimidad a la organización. La principal conclusión indica que una organización con resultados efectivos es capaz de establecer mecanismos basados en la cooperación y el conocimiento, donde la innovación social juega un papel importante para enfrentar situaciones de vulnerabilidad de los grupos organizados.

Resumen en inglés

Many Mexican farmers have formed organizations to work toward common objectives, for example obtaining subsidies and training. The mechanisms that these groups use to achieve their goals and confront situations of change and vulnerability have not been studied in detail. The objective of this study was to analyze the organizational model used by a group of farmers –from the Frailesca region of Chiapas, Mexico– to confront situations of vulnerability and carry out social innovation processes. Using qualitative methods, we analyzed the influence on group performance of: public policy, relationships by which knowledge is exchanged, and values and norms. Results indicate that knowledge exchange within the group, as well as by group members toward other actors, is important for improving production; however, the following are also necessary: effective mechanisms of coordinating collective decision making, experience and capability of developing and implementing sustainable agricultural practices, a facilitator who promotes group cohesion and coordination, and social mechanisms (collective norms, values, sanctions) that provide the organization with legitimacy. The principal conclusion of this study is that a group with effective organizational mechanisms is capable of confronting situations of vulnerability through knowledge, cooperation, and social innovation.