Introdução

Leia a introdução

Programa estatal de cultura y educación ambiental para Zacatecas, México (2010-2017)

Se expone una síntesis de la primera versión del Programa Estatal de Cultura y Educación Ambiental en Condiciones de Cambio Climático para Zacatecas (2010-2017). Comunicación Educativa, Formación y Capacitación para la Sustentabilidad; documento que se encuentra en proceso de validación social, previa publicación. El Programa es un lineamiento de política educativa estatal que, de manera fundamentada para este contexto específico, propone un conjunto de proyectos pertinentes y necesarios a desarrollarse de manera participativa en el seno de la sociedad. El objetivo principal es generar una nueva cultura ambiental que prepare a la población zacatecana para lograr una mejor calidad de vida ante los efectos locales de los fenómenos naturales, biológicos, sociales, económicos y culturales asociados al cambio climático global. Para su elaboración se evaluó el Plan anterior (2002-2010), se consultó a profesores, investigadores y responsables de instancias gubernamentales. El resultado fue un Programa que incluye 6 ámbitos de trabajo, 20 líneas estratégicas y 65 proyectos específicos. Se concluye que para lograr los objetivos propuestos se requiere la participación conjunta de los tres niveles de gobiernos y la colaboración e intervención de los diferentes sectores de la sociedad, organizados bajo una comunicación directa y con voluntad política incluyente y coordinada.Universidad Nacional de La Plat

Programa estatal de cultura y educación ambiental para Zacatecas, México (2010-2017)

Se expone una síntesis de la primera versión del Programa Estatal de Cultura y Educación Ambiental en Condiciones de Cambio Climático para Zacatecas (2010-2017). Comunicación Educativa, Formación y Capacitación para la Sustentabilidad; documento que se encuentra en proceso de validación social, previa publicación. El Programa es un lineamiento de política educativa estatal que, de manera fundamentada para este contexto específico, propone un conjunto de proyectos pertinentes y necesarios a desarrollarse de manera participativa en el seno de la sociedad. El objetivo principal es generar una nueva cultura ambiental que prepare a la población zacatecana para lograr una mejor calidad de vida ante los efectos locales de los fenómenos naturales, biológicos, sociales, económicos y culturales asociados al cambio climático global. Para su elaboración se evaluó el Plan anterior (2002-2010), se consultó a profesores, investigadores y responsables de instancias gubernamentales. El resultado fue un Programa que incluye 6 ámbitos de trabajo, 20 líneas estratégicas y 65 proyectos específicos. Se concluye que para lograr los objetivos propuestos se requiere la participación conjunta de los tres niveles de gobiernos y la colaboración e intervención de los diferentes sectores de la sociedad, organizados bajo una comunicación directa y con voluntad política incluyente y coordinada.Universidad Nacional de La Plat

Nitrogen uptake and internal recycling in Zostera marina exposed to oyster farming: eelgrass potential as a natural biofilter

Oyster farming in estuaries and coastal lagoons frequently overlaps with the distribution of seagrass meadows, yet there are few studies on how this aquaculture practice affects seagrass physiology. We compared in situ nitrogen uptake and the productivity of Zostera marina shoots growing near off-bottom longlines and at a site not affected by oyster farming in San Quintin Bay, a coastal lagoon in Baja California, Mexico. We used benthic chambers to measure leaf NH4 (+) uptake capacities by pulse labeling with (NH4)-N-15 (+) and plant photosynthesis and respiration. The internal N-15 resorption/recycling was measured in shoots 2 weeks after incubations. The natural isotopic composition of eelgrass tissues and vegetative descriptors were also examined. Plants growing at the oyster farming site showed a higher leaf NH4 (+) uptake rate (33.1 mmol NH4 (+) m(-2) day(-1)) relative to those not exposed to oyster cultures (25.6 mmol NH4 (+) m(-2) day(-1)). We calculated that an eelgrass meadow of 15-16 ha (which represents only about 3-4 % of the subtidal eelgrass meadow cover in the western arm of the lagoon) can potentially incorporate the total amount of NH4 (+) excreted by oysters (similar to 5.2 x 10(6) mmol NH4 (+) day(-1)). This highlights the potential of eelgrass to act as a natural biofilter for the NH4 (+) produced by oyster farming. Shoots exposed to oysters were more efficient in re-utilizing the internal N-15 into the growth of new leaf tissues or to translocate it to belowground tissues. Photosynthetic rates were greater in shoots exposed to oysters, which is consistent with higher NH4 (+) uptake and less negative delta C-13 values. Vegetative production (shoot size, leaf growth) was also higher in these shoots. Aboveground/belowground biomass ratio was lower in eelgrass beds not directly influenced by oyster farms, likely related to the higher investment in belowground biomass to incorporate sedimentary nutrients

Seroepidemiology of Toxoplasma gondii infection in pregnant women in a public hospital in northern Mexico

BACKGROUND: Toxoplasma gondii (T. gondii) infection in pregnant women represents a risk for congenital disease. There is scarce information about the epidemiology of T. gondii infection in pregnant women in Mexico. Therefore, we sought to determine the prevalence of T. gondii infection and associated socio-demographic, clinical and behavioural characteristics in a population of pregnant women of Durango City, Mexico. METHODS: Three hundred and forty three women seeking prenatal care in a public hospital of Durango City in Mexico were examined for T. gondii infection. All women were tested for anti-T. gondii IgM and IgG antibodies by using IMx Toxo IgM and IMx Toxo IgG 2.0 kits (Abbott Laboratories, Abbott Park, IL, USA), respectively. Socio-demographic, clinical and behavioural characteristics from each participant were also obtained. RESULTS: Twenty one out of the 343 (6.1%) women had IgG anti-T. gondii antibodies. None of the 343 women had IgM anti-T. gondii antibodies. Multivariate analysis using logic regression showed that T. gondii infection was associated with living in a house with soil floor (adjusted OR = 7.16; 95% CI: 1.39–36.84), residing outside of Durango State (adjusted OR = 4.25; 95% CI: 1.72–10.49), and turkey meat consumption (adjusted OR = 3.85; 95% CI: 1.30–11.44). Other characteristics as cat contact, gardening, and food preferences did not show any association with T. gondii infection. CONCLUSION: The prevalence of T. gondii infection in pregnant women of Durango City is low as compared with those reported in other regions of Mexico and the majority of other countries. Poor housing conditions as soil floors, residing in other Mexican States, and turkey meat consumption might contribute to acquire T. gondii infection

Casimir energy in spherical cavities

We calculate the Casimir energy at spherical cavities within a host made up of an arbitrary material described by a possibly dispersive and lossy dielectric response. To that end, we add to the coherent optical response a contribution that takes account of the incoherent radiation emitted by the host in order to guarantee the detailed balance required to keep the system at thermodynamic equilibrium in the presence of dissipation. The resulting boundary conditions allow a conventional quantum mechanical treatment of the radiation within the cavity from which we obtain the contribution of the cavity walls to the density of states, and from it, the thermodynamic properties of the system. The contribution of the cavity to the energy diverges as it incorporates the interaction energy between neighbor atoms in a continuum description. The change in the energy of an atom situated at the center of the cavity due to its interaction with the fluctuating cavity field is however finite. We evaluate the latter for a simple case.Comment: 9 pages, 4 figures, Proceedings of QFEXT07. To be published in J. Phys.

Immediate impact of COVID-19 pandemic on farming systems in Central America and Mexico

In this article we present a first attempt to understand the immediate impact of COVID-19 and the sanitary measures taken by governments on farming systems in Central America and Mexico (CAM). Through a review of information generated in these initial months of the COVID-19 pandemic (webinars, blogs, electronic publications, media) and 44 interviews with key informants across the region, we have identified the main impacts felt by different types of farming systems in the region. The results presented focus only in the immediate effect of COVID-19 pandemic and the mechanisms implemented by farmers in the first months. Whether these impacts and response mechanisms will result in a transformation of the farming systems towards greater resilience and sustainability is still an open question

Seropositivity and Risk Factors Associated with Toxoplasma gondii Infection in Wild Birds from Spain

Toxoplasma gondii is a zoonotic intracellular protozoan parasite of worldwide distribution that infects many species of warm-blooded animals, including birds. To date, there is scant information about the seropositivity of T. gondii and the risk factors associated with T. gondii infection in wild bird populations. In the present study, T. gondii infection was evaluated on sera obtained from 1079 wild birds belonging to 56 species (including Falconiformes (n = 610), Strigiformes (n = 260), Ciconiiformes (n = 156), Gruiformes (n = 21), and other orders (n = 32), from different areas of Spain. Antibodies to T. gondii (modified agglutination test, MAT titer ≥1∶25) were found in 282 (26.1%, IC95%:23.5–28.7) of the 1079 birds. This study constitute the first extensive survey in wild birds species in Spain and reports for the first time T. gondii antibodies in the griffon vulture (Gyps fulvus), short-toed snake-eagle (Circaetus gallicus), Bonelli's eagle (Aquila fasciata), golden eagle (Aquila chrysaetos), bearded vulture (Gypaetus barbatus), osprey (Pandion haliaetus), Montagu's harrier (Circus pygargus), Western marsh-harrier (Circus aeruginosus), peregrine falcon (Falco peregrinus), long-eared owl (Asio otus), common scops owl (Otus scops), Eurasian spoonbill (Platalea leucorodia), white stork (Ciconia ciconia), grey heron (Ardea cinerea), common moorhen (Gallinula chloropus); in the International Union for Conservation of Nature (IUCN) “vulnerable” Spanish imperial eagle (Aquila adalberti), lesser kestrel (Falco naumanni) and great bustard (Otis tarda); and in the IUCN “near threatened” red kite (Milvus milvus). The highest seropositivity by species was observed in the Eurasian eagle owl (Bubo bubo) (68.1%, 98 of 144). The main risk factors associated with T. gondii seropositivity in wild birds were age and diet, with the highest exposure in older animals and in carnivorous wild birds. The results showed that T. gondii infection is widespread and can be at a high level in many wild birds in Spain, most likely related to their feeding behaviour