22 research outputs found
Cambio climático en DAPA
Presentación del dr. Andrew Jarvis, director de Decision and Policy Analysis del CIAT, durante la primera Casa Abierta de 2013, dirigida a decanos y docentes
Recursos fitogenéticos: bases para un futuro resiliente al clima y libre de hambre en el Caribe
En toda la región Caribe, el cambio climático no solamente planteará desafíos sino también una amplia gama
de oportunidades, que ofrecen mayor importancia a la riqueza de recursos fitogenéticos de la región.
Materializar el potencial de estos recursos para contribuir a garantizar la seguridad alimentaria y crear sistemas
agrícolas más resilientes frente al cambio climático requerirá de una mayor cooperación regional. Los objetivos
centrales de esta cooperación deberán ser: desarrollar intervenciones oportunas en las fronteras nacionales que
mejoren la colecta, conservación y el intercambio de los recursos fitogenéticos
Plant genetic resources: foundations for a food-secure and climate-resilient future in the Caribbean
Across the Caribbean, climate change will bring about not only challenges but also a wide array of opportunities, which lend greater significance to the region’s wealth of plant genetic resources. Realizing the potential of those resources to help ensure food security and build more-resilient agricultural systems in the face of climate change will require stronger regional cooperation. Its central aims should be to develop timely interventions across national borders that improve the collection, conservation, and sharing of plant genetic resources
GABA Regulation of Burst Firing in Hippocampal Astrocyte Neural Circuit: A Biophysical Model
It is now widely accepted that glia cells and gamma-aminobutyric acidergic (GABA) interneurons dynamically regulate synaptic transmission and neuronal activity in time and space. This paper presents a biophysical model that captures the interaction between an astrocyte cell, a GABA interneuron and pre/postsynaptic neurons. Specifically, GABA released from a GABA interneuron triggers in astrocytes the release of calcium (Ca2+) from the endoplasmic reticulum via the inositol 1, 4, 5-trisphosphate (IP3) pathway. This results in gliotransmission which elevates the presynaptic transmission probability rate (PR) causing weight potentiation and a gradual increase in postsynaptic neuronal firing, that eventually stabilizes. However, by capturing the complex interactions between IP3, generated from both GABA and the 2-arachidonyl glycerol (2-AG) pathway, and PR, this paper shows that this interaction not only gives rise to an initial weight potentiation phase but also this phase is followed by postsynaptic bursting behavior. Moreover, the model will show that there is a presynaptic frequency range over which burst firing can occur. The proposed model offers a novel cellular level mechanism that may underpin both seizure-like activity and neuronal synchrony across different brain regions
The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts
Biodiversity continues to decline in the face of increasing anthropogenic pressures
such as habitat destruction, exploitation, pollution and introduction of
alien species. Existing global databases of species’ threat status or population
time series are dominated by charismatic species. The collation of datasets with
broad taxonomic and biogeographic extents, and that support computation of
a range of biodiversity indicators, is necessary to enable better understanding of
historical declines and to project – and avert – future declines. We describe and
assess a new database of more than 1.6 million samples from 78 countries representing
over 28,000 species, collated from existing spatial comparisons of
local-scale biodiversity exposed to different intensities and types of anthropogenic
pressures, from terrestrial sites around the world. The database contains
measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35)
biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains
more than 1% of the total number of all species described, and more than
1% of the described species within many taxonomic groups – including flowering
plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans
and hymenopterans. The dataset, which is still being added to, is
therefore already considerably larger and more representative than those used
by previous quantitative models of biodiversity trends and responses. The database
is being assembled as part of the PREDICTS project (Projecting Responses
of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk).
We make site-level summary data available alongside this article. The full database
will be publicly available in 2015
Amazonia security agenda: summary of findings and initial recommendations
Amazonia’s abundant natural resources underpin water, energy, food and health security for the people and economies of the region and far beyond. At the heart of this nexus of securities is water. So abundant in the region, but now under increasing threat as industrial and agricultural pollution increases, and extreme droughts reveal a once unthinkable water vulnerability
Analysing vulnerability: a multi-dimensional approach from Colombia s upper Cauca river basin
In Colombia, agriculture is an economic mainstay, creating direct employment for much of the country s population. Agriculture s dependence on predictable seasonal patterns leaves many communities vulnerable to climate change. Vulnerability assessments attempt to quantify the degree to which a system will need to adapt to climate change impacts or whether it even has the capacity to do so. Such assessments have been criticised for their uncertainty and lack of applicability at the local or regional scale. However, a project in Colombia s Upper Cauca
River Basin has taken a new approach to vulnerability assessment, using a model based on four dimensions of vulnerability. This brief provides an overview of the project as well as key considerations for vulnerability analyses that are inclusive, integrated and sensitive to social and political complexities
Potential Impact of Road Projects on Habitat Loss and Greenhouse Gas Emissions in Guyana from 2012 to 2022
Deforestation as one of the potential indirect impacts of infrastructure development has increasingly become an important issue in the development community. While questions concerning the drivers and effects of deforestation and how to manage them have been on the minds of project officers and environmental specialists in development banks for many years, the issue of deforestation has gained prominence globally because of the realization that it leads to the potential release of carbon into the atmosphere in addition to being a threat to biodiversity and to ecosystem services. This publication reports the results of a study using the methodology already applied in a previous ex post analysis of five case studies across Latin America. Apart from delivering concrete results that are useful for ongoing IDB projects in Guyana, the study further explores the possibility of using this methodology as a basis for land-use management and in the development of infrastructure projects. The VPS/ESG intends to build on the work presented in this report by reviewing the options available for modeling land-use and land-cover change in Latin America.