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Conocer las capacidades de las Organizaciones de la Sociedad Civil (OSC) para emprender acciones de adaptación al cambio climático es de gran importancia, en tanto son actores clave en la ejecución de políticas públicas en esta materia. El objetivo de esta investigación fue valorar las capacidades de diversas OSC para emprender acciones dirigidas a la adaptación al cambio climático después de su participación en dos proyectos implementados en el Golfo de México en el periodo 2011-2018. La colecta de datos primarios fue a través de encuestas a 23 OSC participantes en los proyectos y mediante entrevistas a siete informantes clave relacionados con los mismos. Los resultados indican que las OSC implicadas fortalecieron sus capacidades de adaptación al cambio climático como resultado de su involucramiento en los proyectos. Su evaluación indicó que cuentan con capacidades de medias a altas y que éstas son independientes de la antigüedad de la OSC. Las OSC con capacidades en temas ambientales han empezado a incorporar acciones para dar respuesta a los impactos del cambio climático para reducir la vulnerabilidad de la población, de los ecosistemas y de los sectores productivos, lo que ha dado como resultado que adquieran nuevos conocimientos en adaptación, permitiéndoles a su vez integrar este enfoque en los proyectos que realizan y gestionan.

The acquisition of neuronal polarity is a complex molecular process that depends on changes in cytoskeletal dynamics and directed membrane traffic, regulated by the Rho and Rab families of small GTPases, respectively. However, during axon specification, a molecular link that couples these protein families has yet to be identified. In this paper, we describe a new positive feedback loop between Rab8a and Cdc42, coupled by Tuba, a Cdc42-specific guanine nucleotide-exchange factor (GEF), that ensures a single axon generation in rodent hippocampal neurons from embryos of either sex. Accordingly, Rab8a or Tuba gain-of-function generates neurons with supernumerary axons whereas Rab8a or Tuba loss-of-function abrogated axon specification, phenocopying the well-established effect of Cdc42 on neuronal polarity. Although Rab8 and Tuba do not interact physically, the activity of Rab8 is essential to generate a proximal to distal axonal gradient of Tuba in cultured neurons. Tuba-associated and Rab8a-associated polarity defects are also evidencedin vivo, since dominant negative (DN) Rab8a or Tuba knock-down impairs cortical neuronal migration in mice. Our results suggest that Tuba coordinates directed vesicular traffic and cytoskeleton dynamics during neuronal polarization.SIGNIFICANCE STATEMENTThe morphologic, biochemical, and functional differences observed between axon and dendrites, require dramatic structural changes. The extension of an axon that is 1 µm in diameter and grows at rates of up to 500 µm/d, demands the confluence of two cellular processes: directed membrane traffic and fine-tuned cytoskeletal dynamics. In this study, we show that both processes are integrated in a positive feedback loop, mediated by the guanine nucleotide-exchange factor (GEF) Tuba. Tuba connects the activities of the Rab GTPase Rab8a and the Rho GTPase Cdc42, ensuring the generation of a single axon in cultured hippocampal neurons and controlling the migration of cortical neurons in the developing brain. Finally, we provide compelling evidence that Tuba is the GEF that mediates Cdc42 activation during the development of neuronal polarity.

The potential impacts of sea level in the study region are presented using the Integrated Procedure for Estimate Sea Level Impacts (IPESLI), made up of Landsat images, official databases, and design software for geographic information systems. IPESLI is useful in areas with little georeferenced and validated information. The sea level projections are based on the climate projections, which incorporate the possible attenuation of the ice sheet near the upper end of Antarctica. Flood risk statistics were used to simulate the frequency of extreme flooding across the planet. The IPESLI was calibrated using seven field visits to compare the height values generated by the digital elevation model against the in situ data. The inundation maps generated in the study can be used to find the most vulnerable areas and initiate decision making for coastal adaptation. The IPESLI procedure has the potential to contribute to the formation of a communication bridge between climate change science and policy makers. The projection is profound for all scenarios, but it is particularly devastating for the Acapulco Diamante area if we start with the worst future climate scenario (SSP5-RCP8.5).

PurposeThis study aims to present the climate change effect on soil moisture regimes in Mexico in a global 1.5°C warming scenario.Design/methodology/approachThe soil moisture regimes were determined using the Newhall simulation model with the database of mean monthly precipitation and temperature at a scale of 1: 250,000 for the current scenario and with the climate change scenarios associated with a mean global temperature increase of 1.5°C, considering two Representative Concentration Pathways, 4.5 and 8.5 W/m2and three general models of atmospheric circulation, namely, GFDL, HADGEM and MPI. The different vegetation types of the country were related to the soil moisture regimes for current conditions and for climate change.FindingsAccording to the HADGEM and MPI models, almost the entire country is predicted to undergo a considerable increase in soil moisture deficit, and part of the areas of each moisture regime will shift to the next drier regime. The GFDL model also predicts this trend but at smaller proportions.Originality/valueThe changes in soil moisture at the regional scale that reveal the impacts of climate change and indicate where these changes will occur are important elements of the knowledge concerning the vulnerability of soils to climate change. New cartography is available in Mexico.

A prominent goal of policies mitigating climate change and biodiversity loss is to achieve zero deforestation in the global supply chain of key commodities, such as palm oil and soybean. However, the extent and dynamics of deforestation driven by commodity expansion are largely unknown. Here we mapped annual soybean expansion in South America between 2000 and 2019 by combining satellite observations and sample field data. From 2000 to 2019, the area cultivated with soybean more than doubled from 26.4 Mha to 55.1 Mha. Most soybean expansion occurred on pastures originally converted from natural vegetation for cattle production. The most rapid expansion occurred in the Brazilian Amazon, where soybean area increased more than tenfold, from 0.4 Mha to 4.6 Mha. Across the continent, 9% of forest loss was converted to soybean by 2016. Soybean-driven deforestation was concentrated at the active frontiers, nearly half located in the Brazilian Cerrado. Efforts to limit future deforestation must consider how soybean expansion may drive deforestation indirectly by displacing pasture or other land uses. Holistic approaches that track land use across all commodities coupled with vegetation monitoring are required to maintain critical ecosystem services. Deforestation is often driven by land conversion for growing commodity crops. This study finds that, between 2000 and 2019, most soybean expansion in South America was on pastures converted originally for cattle production, especially in the Brazilian Amazon. More soy-driven deforestation occurred in the Brazilian Cerrado.

Climate change is considered a serious threat to food security worldwide. In this study, yields of maize, beans, wheat, soybean, sorghum, barley and potato were modeled with 28 future climate change scenarios. Our results reduce the information gap that is frequently reported for Mexico and will contribute to better knowledge on spatial impact of climate change. We applied FAO AquaCrop model for 22 case studies located in 14 states of Mexico. Climate change scenarios were: CNRM, GFDL, HADGEM, MPI and Ensemble REA, with two radiative forcing concentrations (4.5 and 8.5 W m –2 ) and three time horizons (2015-2039, 2045-2069, and 2075-2099). The results show decreases in yields of most of the case studies as a consequence of a decrease in the amount and distribution of precipitation. Maize yield in warm dry climates could decrease up to 84% in the most severe scenarios. Beans could decrease from 10 to 40% in the north of the country, while in the northwest a 15% decrease in wheat yield is predicted. Soybeans could benefit, with increases from 15 to 40%. Sorghum and potatoes are expected to decrease for all the case studies, while barley would have increases and decreases. The results suggest differentiated impacts according to crops and regions studied. We concluded that agriculture requires better focused strategies and policies (attention on crop and spatial distribution).

Emerging evidence shows that Rab11 recycling endosomes (REs Rab11) are essential for several neuronal processes, including the proper functioning of growth cones, synapse architecture regulation and neuronal migration. However, several aspects of REs Rab11 remain unclear, such as its sub-cellular distribution across neuronal development, contribution to dendritic tree organization and its consequences in memory formation. In this work we show a spatio-temporal correlation between the endogenous localization of REs Rab11 and developmental stage of neurons. Furthermore, Rab11-suppressed neurons showed an increase on dendritic branching (without altering total dendritic length) and misdistribution of dendritic proteins in cultured neurons. In addition, suppression of Rab11 in adult rat brains in vivo (by expressing shRab11 through lentiviral infection), showed a decrease on both the sensitivity to induce long-term potentiation and hippocampal-dependent memory acquisition. Taken together, our results suggest that REs Rab11 expression is required for a proper dendritic architecture and branching, controlling key aspects of synaptic plasticity and spatial memory formation. Fil: Siri, Sebastian Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Rozés Salvador, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina Fil: Artur de la Villarmois, Emilce. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; Argentina Fil: Ghersi, Marisa Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; Argentina Fil: Quassollo Infanzon, Gonzalo Emiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Perez, Mariela Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; Argentina Fil: Conde, Cecilia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina

"Las aportaciones de las organizaciones de la sociedad civil (OSC) han sido clave para la implementación de acciones a nivel local en proyectos de adaptación al cambio climático. Por ello, el objetivo de la investigación que presenta este artículo fue analizar la contribución de estas organizaciones a la adaptación en proyectos implementados en México. Se utilizó una metodología con datos de fuentes secundarias y primarias recolectadas mediante encuestas a 23 organizaciones locales del Golfo de México y a través de entrevistas a siete informantes clave de instituciones gubernamentales nacionales y de OSC nacionales y regionales. Esta investigación espera alertar sobre la importancia de las OSC en la adaptación y el fortalecimiento de los procesos y estrategias educativos aplicables para el desarrollo de capacidades de adaptación al cambio climático a través de su interacción con las comunidades."

An assessment of land suitability classes for rainfed maize (spring–summer agricultural cycle) with current climate conditions (1950–2000) and projected climate change scenarios was carried out for Mexico. The method considered the most restrictive factors or agroclimatic requirements from different variables needed by rainfed maize. These factors were analyzed spatially in a geographic information systems (GIS) context, resulting in areas classified into four suitability levels: high, medium, low, and not suitable for maize. We considered two general circulation models (GCM): HADGEM2-ES and MPI-ESM-LR; one radiative forcing concentration representative concentration pathways (RCP) 8.5 Wm−2 and the far period (2075–2099). Results at a national-level analysis showed that under actual conditions, 57.5% of the area of Mexico presents some level of suitability for rainfed maize. The high suitability class is 11.4% of the country, while 20.7% and 25.3% had medium and low suitability levels, respectively. Other results showed that with the HADGEM2-ES and MPI-ESM-LR projections of climate change models, 50.4% and 46.7%, of Mexico’s continental area, respectively, present some level of suitability for the rainfed maize crop. In the first case, with respect to the present climate conditions, the HADGEM2-ES model presented an area decrease of −2.4% and the MPI-ESM-LR model of −5.5% in the high suitability level for the rainfed maize crop. Results at a state-level analysis showed there are five states (Jalisco, Campeche, Oaxaca, Chiapas, and Michoacán) in the interval of more than 50,000 km2 of surface with high and medium suitability levels, with a maximum extent change between the present to the projected climate conditions of −46% for the HADGEM2-ES and −57% for the MPI-ESM-LR. In general, the MPI-ESM-LR model showed the most adverse projected conditions for rainfed maize growth.

Vulnerability to climate change was evaluated for three different time periods: 1990, 2000, and 2010. Our objective was to discuss the scope of a multi-temporal assessment of vulnerability. The method used 55 indicators—with emphasis on the agricultural sector in Mexico—of which 27 were updated for the year 2010 and 33 were retrospectively estimated for the year 1990. The results show that in the 20-year study period, the exposure of the municipalities (and inhabitants) has increased, and sensitivity and adaptive capacity have decreased. The number of municipalities vulnerable to climate change declined over the 20-year period. We found that calculating vulnerability by adding exposure and sensitivity and subtracting adaptive capacity (E + S − AC) can lead to unintentional underestimation of total vulnerability. When rating vulnerability, care must be taken in what is reported: the results differ for the number of inhabitants versus the number of municipalities. Our previous published vulnerability evaluation was for the year 2000, so we wanted to evaluate the sensitivity of some variables and the vulnerability formula itself we used in that moment. It is possible to evaluate the vulnerability multi-temporally, which allows to evaluate the sensibility and calibration of the variables and indicators used and the reconsideration of their application.

Climate change and land use/land cover change (LULCC) are associated with local vulnerability, defined as the intrinsic tendency of a system to be negatively affected by an event or phenomenon, but this can be ameliorated by ecosystem conservation. In Mexico, extensive Wildlife Management Units (eWMUs) are environmental policy instruments designed to promote ecosystem conservation and rural development via the sustainable use of wildlife by local populations. However, evidence of the successful reduction of LULCC by eWMUs is contradictory, and there has been no investigation into their potential as an action to promote climate change adaptation. In this study, we focused on the overall patterns of LULCC associated with eWMU throughout the country and examined strengths and weaknesses of eWMUs as policy instruments to address climate change. In particular, we analyzed how differences in areas with eWMUs influence LULCC and assessed how eWMUs could contribute to reducing vulnerability, particularly in double exposure municipalities. We calculated the percentage of eWMUs per municipality from official information and estimated LULCC from vegetation changes between 2002 and 2011. We then used the Kruskal-Wallis test to find statistically significant differences in vegetation changes based on the percentage of eWMUs and performed between-group comparisons using a post hoc Dunn test. Although Mexico has 2456 municipalities, only 37% have eWMUs. Furthermore, 64% of Mexico’s municipalities have lost vegetation cover, whereas only 36% have either gained vegetation or remained stable. In municipalities that recorded changes to the vegetation, those changes were, overall, minimal and involved less than 10% of the total area of those municipalities. In general, municipalities with less than 10% of their total area dedicated to eWMUs experienced higher vegetation losses than those with more than 10% of their total area dedicated to eWMUs. We detected twelve double exposure municipalities, i.e. they are vulnerable to climate change and lost more than 10% of their vegetation. Double exposure municipalities dedicated less than 2% of their total area to eWMUs as well. Our results suggest that incremental increases in the area dedicated to eWMUs may reduce LULCC and protect vegetation, particularly in double exposure municipalities. Based on the literature, some ecological, economic and socio-cultural factors may determine the success of eWMUs and strongly impact LULCC. Therefore, additional efforts must be made to enhance our understanding of ecological and climatic processes; habitats must be monitored using a standardized methodology; biological, cultural, economic and institutional diversity must be incorporated into the planning, implementation and monitoring of eWMUs; and agreements must be established to strengthen social organization and human capital. Taking all this into account, we suggest that reducing vulnerability and improving double exposure areas by increasing the number and interconnectedness of eWMUs could represent an effective strategic approach at the municipal level to address LULCC and climate change.

The acquisition of neuronal polarity is a complex molecular process that involves several different cellular mechanisms that need to be finely coordinated to define the somatodendritic and axonal compartments. Amongst such mechanisms, cytoskeleton and membrane dynamics control both the morphological transitions that define neuronal polarity acquisition as well as provide molecular determinants to specific sites in neurons at a defined time point. Small GTPases from the Rab and Rho families are well known molecular determinants of neuronal differentiation. However, during axon specification, a molecular link that couples proteins from these two families has yet to be identified. In this paper, we describe the role of Tuba, a Cdc42-specific guanine nucleotide-exchange factor (GEF), in neuronal polarity through a Rab8a-dependent mechanism. Rab8a or Tuba gain-of-function generates neurons with supernumerary axons whereas Rab8a or Tuba loss-of-function abrogated axon specification, phenocopying the well-established effect of Cdc42 on neuronal polarity. Neuronal polarization associated to Rab8a is also evidencedin vivo, since a dominant negative version of Rab8a severely impaired neuronal migration.Remarkably, Rab8a activates Cdc42 in a Tuba-dependent manner, and dominant negative mutants of both GTPases reciprocally prevent the effect over polarity acquisition in the gain-of-function scenarios. Our results strongly suggest that a positive feedback loop linking Rab8a and Cdc42 activities via Tuba, is a primary event in neuronal polarization. In addition, we identified the GEF responsible for Cdc42 activation that is essential to specify axons in cultured neurons.

Local knowledge can be a strategy for coping with extreme events and adapting to climate change. In Mexico, extreme events and climate change projections suggest the urgency of promoting local adaptation policies and strategies. This paper provides an assessment of adaptation actions based on the local knowledge of coffee farmers in southern Mexico. The strategies include collective and individual adaptation actions that farmers have established. To determine their viability and impacts, carbon stocks and fluxes in the system’s aboveground biomass were projected, along with water balance variables. Stored carbon contents are projected to increase by more than 90%, while maintaining agroforestry systems will also help serve to protect against extreme hydrological events. Finally, the integration of local knowledge into national climate change adaptation plans is discussed and suggested with a local focus. We conclude that local knowledge can be successful in conserving agroecological coffee production systems.

In the version of this Perspective originally published, the footnote of Table 1 incorrectly described the meanings of symbols in the table, and the tick marks paired with obeli symbols should have been + signs. The symbols have been amended, as has the footnote, which now reads “Tick marks indicate recommendations made to address the issue in the indicated column; + signs indicate benefits to additional issues”. The online versions of the Perspective have been corrected.

The development and maintenance of multicellular organisms require specialized coordination between external cellular signals and the proteins receiving stimuli and regulating responses. A critical role in the proper functioning of these processes is played by endosomal trafficking, which enables the transport of proteins to targeted sites as well as their return to the plasma membrane through its essential components, the endosomes. During this trafficking, signaling pathways controlling functions related to the endosomal system are activated both directly and indirectly. Although there are a considerable number of molecules participating in these processes, some are more known than others for their specific functions. Toward the end of the 1990s, Smad anchor for receptor activation (SARA) protein was described to be controlling and to facilitate the localization of Smads to transforming growth factor β (TGF-β) receptors during TGF-β signaling activation, and, strikingly, SARA was also identified to be one of the proteins that bind to early endosomes (EEs) participating in membrane trafficking in several cell models. The purpose of this review is to analyze the state of the art of the contribution of SARA in different cell types and cellular contexts, focusing on the biological role of SARA in two main processes, trafficking and cellular signaling, both of which are necessary for intercellular coordination, communication, and development.

Summary The neuronal Golgi apparatus (GA) localizes to the perinuclear region and dendrites as tubulo-vesicular structures designated Golgi outposts (GOPs). Current evidence suggests that GOPs shape dendrite morphology and serve as platforms for the local delivery of synaptic receptors. However, the mechanisms underlying GOP formation remain a mystery. Using live-cell imaging and confocal microscopy in cultured hippocampal neurons, we now show that GOPs destined to major "apical" dendrites are generated from the somatic GA by a sequence of events involving: (1) generation of a GA-derived tubule; (2) tubule elongation and deployment into the dendrite; (3) tubule fission; and (4) transport and condensation of the fissioned tubule. A RhoA-Rock signaling pathway involving LIMK1, PKD1, slingshot, cofilin, and dynamin regulates polarized GOP formation by controlling the tubule fission. Our observations identify a mechanism underlying polarized GOP biogenesis and provide new insights regarding involvement of RhoA in dendritic development and polarization. Fil: Quassollo Infanzon, Gonzalo Emiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Wojnacki Fonseca, José Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Salas, Daniela A.. Universidad de Chile; Chile Fil: Gastaldi, Laura Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Marzolo, María Paz. Pontificia Universidad Católica de Chile; Chile Fil: Conde, Cecilia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina. Instituto Universitario de Ciencias Biomédicas de Córdoba; Argentina Fil: Bisbal, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina. Instituto Universitario de Ciencias Biomédicas de Córdoba; Argentina Fil: Couve, Andrés. Universidad de Chile; Chile Fil: Caceres, Alfredo Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina. Instituto Universitario de Ciencias Biomédicas de Córdoba; Argentina

The science is clear, students are striking, and publics around the globe are demanding a new level of leadership to tackle the climate crisis before it is too late. Climate extremes are inflicting serious economic losses on nations, and climate-driven issues such as sea-level rise, regional aridification, food shortages, disease spread, and massive biodiversity loss only promise ever-worsening costs. Progress has been too slow since 195 countries signed the 2015 Paris Agreement committing to hold the increase in the global average temperature to well below 2°C above preindustrial levels. To prevent planetary climate disaster, we must all work to speed up bold initiatives that ensure a rapid exit from the era of fossil fuels, and drive carbon dioxide and other greenhouse gas emissions to the atmosphere down to zero in a manner that benefits everyone on the planet, not just a few. Much attention has been focused on promoting the transition to low-carbon energy because of the role that fossil fuel combustion has played in fouling the air and disrupting climate. Moreover, the technology needed to electrify the planet using renewable energy is already, or close to being, cheaper than fossil fuel or nuclear energy, so the existing fossil fuel power plants and fossil-fueled transportation can be phased out completely within two decades. Investment in new fossil fuel infrastructure must cease as existing natural gas and nuclear plants serve only as temporary bridges to a cleaner-energy world. At the same time, every economic sector must innovate to become more energy efficient and decarbonize. With continued innovation, the effective management of marine, coastal, agricultural, forest, and other carbon-sequestering systems can help offset those greenhouse emissions that cannot be eliminated quickly. The circle of solutions to address the climate crisis must quickly widen and include effective ways to soften the blows of climate change that are already inevitable. Solutions must strive to enable communities, businesses, societies, and natural systems to become resilient and adapt to the changing climate. The rapid expansion of adaptation strategies around the globe requires greater integration of academic research knowledge with the insight gained from real-world practice, and this means placing greater priority on partnership between academics and nonacademics. Nevertheless, it is also abundantly clear that absent climate change mitigation, adaptation strategies will in many cases become overwhelmed, leading to unacceptable costs to both human and natural systems. The top priority must remain the elimination of the greenhouse gas emissions that are driving climate change, and greater emphasis must be placed on positive synergies between mitigation and adaptation actions, especially those that maximize the protection of biodiversity and soils. The climate crisis requires societal transformation of a scale and rapidity that has rarely been achieved. Indeed, the last time such a change took place was sparked by global economic depression and World War II. What enabled action then was a perceived existential threat and broad support in society. Today, we are faced with such a threat, but widening wealth disparities and special interests impede the needed change. The solution to the climate crisis thus requires a strong commitment to equity and justice, to indigenous peoples and future generations, and to a global transformation that vastly increases the number of those who benefit while dramatically reducing the number of those who do not. This is true at national scales, and also at the planetary scale. Only by working together across divides, only by working to empower others, and only by making it a top priority now can the community of nations avoid catastrophic climate change while creating a more sustainable and just 21st century. The call to faster climate action is to all who can contribute knowledge, momentum, or passion to drive the quick embrace of effective solutions.

An index with the potential to integrate different climate hazards into a single parameter is required to guide preventive decision making. We integrated in a single index the degree of exposure to climate that the nation's municipalities have. We selected this spatial scale because the municipality is the basic unit of administrative and economic planning; consequently, this is the scale at which policies of adaptation to climate change must be fostered. We conceptualized exposure as the sum of historic extreme events, the degree of ecosystem conservation and current climate and its future scenarios. This approach allowed us to create a climate hazard exposure index at the municipality scale integrating past and present. Maps of this index can be constructed to serve as a medium of risk communication and to aid policy design. We used information from eighteen variables to statistically standardize and compute the hazard exposure index by applying empirical formulae. We found that actually, out of ten Mexicans, three live in flood-prone zones, three may suffer the passage of tropical cyclones, five reside in drought zones and two live in extreme drought regions. Additionally, hailstorms affect five out of ten Mexicans, while eight out of ten are affected by frosts. Incorporating climate change, in the future more municipalities and a higher population will live in high exposure. Because understanding exposure is a necessary prerequisite to understanding vulnerability, knowledge of the spatial distribution of exposure should be useful for reducing the identified climate hazard exposure and vulnerability to climate change.

"In recent years in Mexico and around the world, the scientific community has shown great interest in acquir - ing knowledge regarding the behavior of extreme climate events due to their increasing number and inten - sity. The objective of this research was to analyze variations in extreme temperature events using extreme climate indices. We conducted a case study for the municipality of Apizaco, Tlaxcala, Mexico, using data sets of the daily maximum and minimum temperatures for the period from 1952 to 2003. Six indices related to maximum and minimum temperatures were calculated: frost days, summer days, warm days, cool days, warm nights and cool nights. All of the index results were evaluated annually and only four of the indices were analyzed according to the seasons. A trend based on a linear least squares regression model was fit to the indices to determine their behavior. The index results showed that extreme events related to maximum temperatures corresponded to greater changes and an increased number of summer days and decreased cool days. Additionally, there was an increase of frost days, associated with a greater number of days with minimum temperatures below 0 ºC. In general, the results indicated that warmer and colder extreme temperatures are occurring. The detection of those trends in the extreme events can be seen as a first step in any study of the attribution of those observed changes ( e.g. , land use change, regional climate change, etc.). This attribution aspect will not be discussed in the present study."

Emerging evidence suggests that endocytic trafficking of adhesion proteins plays a crucial role in neuronal migration during neocortical development. However, molecular insights into these processes remain elusive. Here, we study the early endosomal protein Smad anchor for receptor activation (SARA) in the developing mouse brain. SARA is enriched at the apical endfeet of radial glia of the neocortex. Although SARA knockdown did not lead to detectable neurogenic phenotypes, SARA-suppressed neurons exhibited impaired orientation and migration across the intermediate zone. Mechanistically, we show that SARA knockdown neurons exhibit increased surface expression of the L1 cell adhesion molecule. Neurons ectopically expressing L1 phenocopy the migration and orientation defects caused by SARA knockdown and display increased contact with neighboring neurites. L1 knockdown effectively rescues SARA suppressioninduced phenotypes. SARA knockdown neurons eventually overcome their migration defect and enter later into the cortical plate. Nevertheless, these neurons localize at more superficial cortical layers than their control counterparts. These results suggest that SARA regulates the orientation, multipolar-to-bipolar transition and the positioning of cortical neurons via modulating surface L1 expression. Fil: Mestres Lascano, Ivan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Chuang, Jen-Zen. Cornell University; Estados Unidos Fil: Calegari, Federico. Dfg-research Center For Regenerative Therapies; Alemania Fil: Conde, Cecilia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Sung, Ching-Hwa. Cornell University; Estados Unidos

"El estudio de la gestión de riesgos ante los eventos hidrometeorológicos extremos es un componente fundamental para que los sistemas de alerta temprana puedan resultar instrumentos de respuesta efectiva. En este artículo se analiza la gestión del riesgo por eventos extremos de precipitación por parte de los funcionarios municipales del estado de Veracruz y se comparan las regiones norte, centro y sur de la entidad. Se aplicó un cuestionario en materia de protección civil a funcionarios de 58 municipios del estado de Veracruz, que representan 27 % del total y abarcan 40 % del territorio veracruzano. Se obtuvo información sobre su grado de escolaridad, conocimiento de su función, así como sus formas de actuación antes, durante y después de la presencia de eventos extremos de precipitación. Los resultados mostraron que el máximo grado de estudios de la mayoría de los entrevistados fue maestría (38 %). Las organizaciones actúan antes, durante y después de un evento extremo de precipitación con 73 % para la zona norte y 36 % para las zonas centro y sur. Por último, se observó que los gobiernos municipales por lo general se limitan a la emisión de alertas meteorológicas y a las actividades relacionadas con albergues. Se recomienda la capacitación y la comunicación como estrategias esenciales para reducir la vulnerabilidad y aumentar la resiliencia en materia de cambio climático."

We applied two methods to assess vulnerability to climate change in Mexico’s agricultural sector. The first one was a principal component analysis (PCA) that weighted each variable separately. For the second one, we integrated the variables in a linear array in which all variables were weighted equally, and then, we used the arithmetic sum of the sub-indices of exposure and sensitivity minus the adaptive capacity to obtain the vulnerability index. We discuss the similarities and differences between two methods with respect to municipal-level maps as the outputs. The application of the method for the agricultural sector in Mexico gave us the spatial distribution of the high- and very-high vulnerability categories, which we propose as a tool for policy. The methods agreed that the very-high vulnerability category is present in 39 municipalities. Also we found that 16 % of the total population in the country is located in high-exposure areas. In addition, 41 % lives in municipalities identified as highly-sensitive. In terms of adaptive capacity, 20 % of the population lives in 1273 municipalities with low-adaptive capacity. Finally, we discuss the need for information regarding vulnerability at the national level to guide policies aimed at reducing exposure and sensitivity and increasing adaptive capacity.

This paper presents a review of the methodology applied for generating the regional climate change scenarios utilized in important National Documents of Mexico, such as the Fourth National Communication to the United Nations Framework Convention on Climate Change, the Fourth National Report to the Convention on Biological Diversity and The Economics of Climate Change in Mexico. It is shown that these regional climate change scenarios, which are one of the main inputs to support the assessments presented in these documents, are an example of the erroneous use of statistical downscaling techniques. The arguments presented here imply that the work based on such scenarios should be revised and therefore, these documents are inadequate for supporting national decision- making. © 2011 Springer Science+Business Media B.V.

RhoA and Rac play key and opposite roles during neuronal polarization. We now show that Lfc, a guanosine nucleotide exchange factor (GEF), localizes to the Golgi apparatus and growth cones of developing neurons and negatively regulates neurite sprouting and axon formation through a Rho signaling pathway. Tctex-1, a dynein light chain implicated in axon outgrowth by modulating actin dynamics and Rac activity, colocalizes and physically interacts with Lfc, thus inhibiting its GEF activity, decreasing Rho-GTP levels, and functionally antagonizing Lfc during neurite formation.

During the past decade enormous advances have been made in our understanding of the basic molecular machinery that is involved in the development of neuronal polarity. Far from being mere structural elements, microtubules are emerging as key determinants of neuronal polarity. Here we review the current understanding of the regulation of microtubule assembly, organization and dynamics in axons and dendrites. These studies provide new insight into microtubules' function in neuronal development and their potential contribution to plasticity.

In non-neuronal cells, inactivation of protein kinase D (PKD) blocks fission oftrans-Golgi network (TGN) transport carriers, inducing the appearance of long tubules filled with cargo. We now report on the function of PKD1 in neuronal protein trafficking. In cultured hippocampal pyramidal cells, the transferrin receptor (TfR) and the low-density receptor-related protein (LRP) are predominantly transported to dendrites and excluded from axons. Expression of kinase-inactive PKD1 or its depletion by RNA interference treatment dramatically and selectively alter the intracellular trafficking and membrane delivery of TfR- and LRP-containing vesicles, without inhibiting exit from the TGN or inducing Golgi tubulation. After PKD1 suppression, dendritic membrane proteins are mispackaged into carriers that transport VAMP2; these vesicles are distributed to both axons and dendrites, but are rapidly endocytosed from dendrites and preferentially delivered to the axonal membrane. A kinase-defective mutant of PKD1 lacking the ability to bind diacylglycerol and hence its Golgi localization does not cause missorting of TfR or LRP. These results suggest that in neurons PKD1 regulates TGN-derived sorting of dendritic proteins and hence has a role in neuronal polarity.

SARA (Smad Anchor for Receptor Activation) plays a crucial role in Rab5-mediated endocytosis in cell lines localizing to early endosomes where it regulates morphology and function. Here, we analyzed the role of SARA during neuronal development and tested whether it functions as a regulator of endocytic trafficking of selected axonal and membrane proteins. Suppression of SARA perturbs the appearance of juxtanuclear endocytic recycling compartments and the neurons show long axons with large growth cones. Furthermore, surface distribution of the cell adhesion molecule L1 in axons and the fusion of vesicles containing transferring receptor (TfR) in dendrites were increased in neurons where SARA was silenced. Conversely, SARA overexpression generated large early endosomes and reduced neurite outgrowth. Taken together, our findings suggest a significant contribution of SARA to key aspects of neuronal development, including neurite formation. Copyright: Fil: Arias, Cristina Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Siri, Sebastian Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Conde, Cecilia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina

An analysis of current trends in water availability in the Mexican border state of Sonora is presented to illustrate what may be faced under climate change conditions. Precipitation, streamflow and even dam levels data are examined to estimate what changes have been experienced in recent decades. There are indications that the more frequent occurrence of El Nino/Southern Oscillation (ENSO) events have resulted in more winter precipitation and consequently in a slight increase in water availability in northwestern Mexico. However, water demands grow much faster than such trends in water availability, mainly due to a rapid increase in population in urban areas and in socio-economic activities such as those related to agriculture, industry and power generation. Some strategies to adapt or mitigate climate change conditions are proposed.

Retina photoreceptor and ganglion cells isolated from chicks that in vivo were exposed to light have a different phospholipid labeling capacity than those from chicks in the dark. In the light exposed animals, the phospholipid labeling in the ganglion cells is higher (Delta% 45, p

Slow saccades, postural/intention tremor, peripheral neuropathy, and decreased deep-tendon reflexes are valuable neurological signs for clinical suspicion of spinocerebellar ataxia type 2 (SCA2). We report the presence of abnormally brisk deep-tendon reflexes in nonsymptomatic carriers and mildly and severely affected subjects of a large Argentinean SCA2 pedigree. The identification of this distinctive SCA2 phenotype in an entire pedigree reinforces the current concept that clinical algorithms are of limited value as indicators for genetic testing in SCA. Combined with published pedigrees of SCA2 manifesting as levodopa-responsive parkinsonism, this finding suggests that modifier genes could influence the clinical phenotype of SCA2. © 2005 Movement Disorder Society

Oxidized lipoproteins have been involved in the pathogenesis of atherosclerosis and atherosclerotic lesions contain oxidized low density lipoprotein. Conversely, the presence of oxidized high density lipoprotein (HDL) in vivo has not been clearly established. Oxidation of HDL in vitro models produces an increase in peroxidized lipids and the appearance of apolipoprotein A-I (apo A-I) oligomers. We investigated the oxidative status of HDL in an in vivo model: the hypercholesterolemic chicken. The HDLs from control and hyperlipemic animals were analyzed for the content of lipid peroxides employing spectroscopic and fluorescence techniques, for the level of apo A-I oligomerization, and for susceptibility to in vitro oxidation. HDL from hypercholesterolemic chickens was more peroxidized (as detected by fluorescence), had higher amount of oligomeric apo A-I, and was oxidized to a greater extent by uv irradiation than that of control animals. We speculate that apo A-I oligomerization could be a key step in the atheroma formation.

A previously described inhibitor of the UDP-N-acetylgalactosamine: GM3, N-acetylgalactosaminyltransferase (GalNAc-T) (Quiroga et al., 1,2), was purified from chicken blood serum by a new procedure. When subjected to SDS-PAGE, two major polypeptides of 27 and 70 kDa were observed. When tested in vitro, only the 27 kDa polypeptide inhibited the GalNAc-T. When added to chick cerebral embryonic neurons in culture, both polypeptides inhibited neuritogenesis. Both the 27 kDa and the 70 kDa fractions were present in the cells at 3 h following their addition to the cultures; both polypeptides had aneuritogenic activity and both inhibited the incorporation of [3H]-galactose into the cell gangliosides modifying their labeling pattern to a similar extent. Sequencing of the amino terminal end of the polypeptides showed that 18 and 9 amino acids from, respectively, the 27 and the 70 kDa polypeptides, were 100% homologues with the corresponding region of chick apolipoprotein A1 (apo A1). After addition to cells in culture, no interconversion between the two polypeptides was detected after up to 20 h in culture. A monoclonal antibody that recognizes only the 70 kDa polypeptide, blocks its aneuritogenic effect without modifying that of the 27 kDa fraction. It is concluded that the endogenous inhibitor of GalNAc-T is apo A1.

People have evolved ways of earning livelihoods and supplying their needs for food, water, shelter and other goods and services that are adapted to the climates of the areas in which they live. But the climate is ever variable and changeable, and deviations that are too far from the norm can be disruptive, even hazardous.