25 research outputs found

    Fog interception by Ball moss (<i>Tillandsia recurvata</i>)

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    Interception losses are a major influence in the water yield of vegetated areas. For most storms, rain interception results in less water reaching the ground. However, fog interception can increase the overall water storage capacity of the vegetation and once the storage is exceeded, fog drip is a common hydrological input. Fog interception is disregarded in water budgets of semiarid regions, but for some plant communities, it could be a mechanism offsetting evaporation losses. <i>Tillandsia recurvata</i> is a cosmopolitan epiphyte adapted to arid habitats where fog may be an important water source. Therefore, the interception storage capacity by <i>T. recurvata</i> was measured in controlled conditions and applying simulated rain or fog. Juvenile, vegetative specimens were used to determine the potential upperbound storage capacities. The storage capacity was proportional to dry weight mass. Interception storage capacity (<i>C</i><sub>min</sub>) was 0.19 and 0.56 mm for rainfall and fog respectively. The coefficients obtained in the laboratory were used together with biomass measurements for <i>T. recurvata</i> in a xeric scrub to calculate the depth of water intercepted by rain. <i>T. recurvata</i> contributed 20 % to the rain interception capacity of their shrub hosts: <i>Acacia farnesiana</i> and <i>Prosopis laevigata</i> and; also potentially intercepted 4.8 % of the annual rainfall. Nocturnal stomatic opening in <i>T. recurvata</i> is not only relevant for CO<sub>2</sub> but for water vapor, as suggested by the higher weight change of specimens wetted with fog for 1 h at dark in comparison to those wetted during daylight (543 ± 77 vs. 325 ± 56 mg, <i>p</i> = 0.048). The storage capacity of <i>T. recurvata</i> leaf surfaces could increase the amount of water available for evaporation, but as this species colonise montane forests, the effect could be negative on water recharge, because potential storage capacity is very high, in the laboratory experiments it took up to 12 h at a rate of 0.26 l h<sup>−1</sup> to reach saturation conditions when fog was applied

    Urban agroecology enhances agrobiodiversity and resilient, biocultural food systems. The case of the semi-dryland and medium-sized Querétaro City, Mexico

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    Small-scale agroecological practices in the urban areas of Querétaro, México, as in other mid-sized cities, could maintain agrobiodiversity pools and sufficient productivity for a food sovereignty baseline. The application of agroecological principles fosters agrobiodiversity and socio-ecological resilience in urban food production. Emerging urban gardens result from an immediate necessity for food that does not appear in local statistics, nor is there any account of them in any cadastral source or land register of Querétaro City. Based on studies of 28 urban gardens, we survey and analyze farming practices using socio-ecological resilience methodologies and the Diagnostic Survey of Agroecological Practices. We find that the agroecological management of urban gardens results in significantly more species richness than in conventionally managed plots, likely due to the multifunctional purposes associated with biocultural memory. The number of social actors participating in agroecological management is increasing. It represents an urban strategy of resilience that contributes to enhancing the microclimate and nutrient cycling, as well as to improving water management and biodiversity. Results also indicate that gardens of approximately 200 m2 harbor the highest levels of agrobiodiversity. This area size for home vegetable production appears optimal for user-friendly management practices in urban settings and could represent the minimum benchmark for a family and a goal for urban planning and policy recommendations. Urban gardens contribute to the adaptive capacities of city dwellers to enhance their food security and sovereignty. Therefore, given that 70% of the national population face some level of food insecurity, we argue that, along with the protection of land-use rights, the promotion of a diverse urban landscape could improve long-term socio-ecological and food supply resilience. Additionally, urban gardens promote neighborhood social inclusion and affordable access to food. The empirical results and insights from this study in Querétaro can inform land-use policies for urban agriculture more broadly, especially in Latin American metropolitan areas

    Construyendo resiliencia socioecológica en huertos urbanos y periurbanos en Querétaro; adaptaciones urbanas ante el desafío de la soberanía alimentaria y el cambio climático : Hacia la activación de un diálogo de saberes de urbicultor a urbicultor

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    La resiliencia socioecológica depende tanto de las amenazas, la vulnerabilidad y de la capacidad adaptativa de sistemas agroecológicos para diversificar, promover interacciones y sinergias benéficas entre sus componentes, regenerar la fertilidad del suelo, mantener la productividad, proteger los cultivos y recuperarse de los daños causados. Se evaluará la resiliencia socioecológica de los 28 huertos urbanos identificados en la zona urbana y metropolitana de Querétaro en el contexto del cambio climático. Desde la metodología interdisciplinaria de la agroecología se medirá la composición botánica, la productividad agrícola y el aporte nutricional, la calidad del suelo y de la descripción del manejo según la caracterización de los Sistemas Agrícolas Mixtos de los 28 huertos identificados, activando el Diálogo de saberes con los dueños o urbicultores. La causa de la crisis del sistema alimentario no subyace en la falta de disponibilidad de alimento como en la crisis estructural social de exclusión y desigualdad económica que limita su acceso.The socio-ecological resilience depends on the threats, vulnerability and adaptive capacity of agro-ecosystems to diversify, promote beneficial interactions and synergies between its components, regenerate soil fertility, maintain productivity, protect crops and recover from damage. The socio-ecological resilience of 29 identified urban gardens in urban and metropolitan area of Queretaro in the context of climate change, will be assessed. From an interdisciplinary approach to agroecology, the botanical composition, agricultural productivity and nutritional value, soil quality and description of management will be measured by the characterization of the mixed farming systems of the 28 gardens by activating the knowledge dialogue with the owners or urbicultores. The cause of the crisis in the food system lies not in the lack of availability of food as in the structural crisis of social exclusion and economic inequality, which limits their access.Eje: A1 Sistemas de producción de base agroecológica (Trabajos científicos)Facultad de Ciencias Agrarias y Forestale

    Construyendo resiliencia socioecológica en huertos urbanos y periurbanos en Querétaro; adaptaciones urbanas ante el desafío de la soberanía alimentaria y el cambio climático : Hacia la activación de un diálogo de saberes de urbicultor a urbicultor

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    La resiliencia socioecológica depende tanto de las amenazas, la vulnerabilidad y de la capacidad adaptativa de sistemas agroecológicos para diversificar, promover interacciones y sinergias benéficas entre sus componentes, regenerar la fertilidad del suelo, mantener la productividad, proteger los cultivos y recuperarse de los daños causados. Se evaluará la resiliencia socioecológica de los 28 huertos urbanos identificados en la zona urbana y metropolitana de Querétaro en el contexto del cambio climático. Desde la metodología interdisciplinaria de la agroecología se medirá la composición botánica, la productividad agrícola y el aporte nutricional, la calidad del suelo y de la descripción del manejo según la caracterización de los Sistemas Agrícolas Mixtos de los 28 huertos identificados, activando el Diálogo de saberes con los dueños o urbicultores. La causa de la crisis del sistema alimentario no subyace en la falta de disponibilidad de alimento como en la crisis estructural social de exclusión y desigualdad económica que limita su acceso.The socio-ecological resilience depends on the threats, vulnerability and adaptive capacity of agro-ecosystems to diversify, promote beneficial interactions and synergies between its components, regenerate soil fertility, maintain productivity, protect crops and recover from damage. The socio-ecological resilience of 29 identified urban gardens in urban and metropolitan area of Queretaro in the context of climate change, will be assessed. From an interdisciplinary approach to agroecology, the botanical composition, agricultural productivity and nutritional value, soil quality and description of management will be measured by the characterization of the mixed farming systems of the 28 gardens by activating the knowledge dialogue with the owners or urbicultores. The cause of the crisis in the food system lies not in the lack of availability of food as in the structural crisis of social exclusion and economic inequality, which limits their access.Eje: A1 Sistemas de producción de base agroecológica (Trabajos científicos)Facultad de Ciencias Agrarias y Forestale

    Open access simulation toolbox for the grid connection of offshore wind farms using multi-terminal HVDC networks

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    Decarbonisation of the European electricity system can become dauntingly costly due to transmission and distribution network issues arising from the integration of intermittent renewable generation sources. It is expected that wind energy will be the principal renewable source by 2050 and, as such, a number of initiatives in the academia and in the industry are being carried out to propose solutions to best accommodate the wind resource. This paper presents work carried out by DEMO 1 partners within the EU FP7 project BEST PATHS. A MATLAB/Simulink toolbox consisting of the necessary building blocks for the simulation and integration of offshore wind farms using enabling technologies such as multiterminal high-voltage direct-current grids is presented. To illustrate the toolbox capabilities, a number of system topologies is studied. System performance is assessed and measured against a set of key performance indicators. To ensure knowledge dissemination, the toolbox has been made available as open access in the BEST PATHS project website

    HIV/STI co-infection among men who have sex with men in Spain

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    In Spain, neither the HIV nor the STI national surveillance systems collect information on HIV/STI co-infection. However, there are two networks based on HIV/STI clinics which gather this data. We describe HIV prevalence in men who have sex with men (MSM) diagnosed with infectious syphilis and/or gonorrhoea in 15 STI clinics; and concurrent diagnoses of STI in MSM newly diagnosed with HIV in 19 HIV/STI clinics. In total, 572 MSM were diagnosed with infectious syphilis and 580 with gonorrhoea during 2005-2007. HIV prevalence among syphilis and gonorrhoea cases was 29.8% and 15.2% respectively. In the multivariate analysis, HIV/syphilis co-infection was associated with being Latin American; having a history of STI; reporting exclusively anal intercourse; and having sex with casual or several types of partners. HIV and gonorrhoea co-infection was associated with age older than 45 years; having no education or only primary education completed; and having a history of STI. In total, 1,462 HIV infections were newly diagnosed among MSM during 2003-2007. Of these, 31.0% were diagnosed with other STI at the same time. Factors associated with STI co-infection among new HIV cases in MSM were being Latin American; and having sex with casual partners or with both steady and casual partners. In Spain, a considerable proportion of MSM are co-infected with HIV and STI.This work was funded by two grants (36646/07; 36794/08) from the Foundation for Research and Prevention of AIDS in Spain (Fundación para la Investigación y la Prevención del SIDA en España–FIPSE).S

    Population-based multicase-control study in common tumors in Spain (MCC-Spain): rationale and study design

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    Introduction: We present the protocol of a large population-based case-control study of 5 common tumors in Spain (MCC-Spain) that evaluates environmental exposures and genetic factors. Methods: Between 2008-2013, 10,183 persons aged 20-85 years were enrolled in 23 hospitals and primary care centres in 12 Spanish provinces including 1,115 cases of a new diagnosis of prostate cancer, 1,750 of breast cancer, 2,171 of colorectal cancer, 492 of gastro-oesophageal cancer, 554 cases of chronic lymphocytic leukaemia (CLL) and 4,101 population-based controls matched by frequency to cases by age, sex and region of residence. Participation rates ranged from 57% (stomach cancer) to 87% (CLL cases) and from 30% to 77% in controls. Participants completed a face-to-face computerized interview on sociodemographic factors, environmental exposures, occupation, medication, lifestyle, and personal and family medical history. In addition, participants completed a self-administered food-frequency questionnaire and telephone interviews. Blood samples were collected from 76% of participants while saliva samples were collected in CLL cases and participants refusing blood extractions. Clinical information was recorded for cases and paraffin blocks and/or fresh tumor samples are available in most collaborating hospitals. Genotyping was done through an exome array enriched with genetic markers in specific pathways. Multiple analyses are planned to assess the association of environmental, personal and genetic risk factors for each tumor and to identify pleiotropic effects. Discussion: This study, conducted within the Spanish Consortium for Biomedical Research in Epidemiology & Public Health (CIBERESP), is a unique initiative to evaluate etiological factors for common cancers and will promote cancer research and prevention in Spain.The study was partially funded by the “Accion Transversal del Cancer”, approved on the Spanish Ministry Council on the 11th October 2007, by the Instituto de Salud Carlos III-FEDER (PI08/1770, PI08/0533, PI08/1359, PS09/00773, PS09/01286, PS09/01903, PS09/02078, PS09/01662, PI11/01403, PI11/01889, PI11/00226, PI11/01810, PI11/02213, PI12/00488, PI12/00265, PI12/01270, PI12/00715, PI12/00150), by the Fundación Marqués de Valdecilla (API 10/09), by the ICGC International Cancer Genome Consortium CLL, by the Junta de Castilla y León (LE22A10-2), by the Consejería de Salud of the Junta de Andalucía (PI-0571), by the Conselleria de Sanitat of the Generalitat Valenciana (AP 061/10), by the Recercaixa (2010ACUP 00310), by the Regional Government of the Basque Country by European Commission grants FOOD-CT- 2006-036224-HIWATE, by the Spanish Association Against Cancer (AECC) Scientific Foundation, by the The Catalan Government DURSI grant 2009SGR1489

    Desarrollo de Pinus pseudostrobus bajo distintos ambientes de crecimiento en jardín común.

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    From a principal component analysis (PCA), is is proposed the interpretation and classification of three main environments competition on the development of individuals of P. pseudostrobus integrating previous results within the same trial. The variables were: growth (height and base diameter), chlorophyll production (chlorophyll pigments total, a, b and the ratio a/b), survival, production and distribution of dry weight biomass (total biomass of root, branch, leaf and stem) and growth architecture (length of branch insertion height and the lowest branch on the stem). All variables were measured in half-sibling families of P. pseudostrobus in a common garden test for 10 months-old seedlings in three competitive environments: (I) inter-family of low density (0.24 × 0.12 m), (II) inter-family of high density (0.12 × 0.06 m) and (III) intra-family with high density (0.12 × 0.06 m). The first three components (PC) explained 82.9% of the total variation. The growth was the major component (PC1), grouping families for competitive environments as PC2 with families grouped by survivability and physiological plasticity, and finally, architectural structural changes as PC3. The results showed a high level of phenotypic plasticity of P. pseudostrobus, and emphasize the importance of the selection of environments and genotypes consistent to enhance adaptation and productivity improvement programs.A partir de un análisis de componentes principales (ACP), se plantea la interpretación y clasificación de tres ambientes de competencia sobre el desarrollo de individuos de P. pseudostrobus integrando resultados previamente publicados dentro del mismo ensayo; las variables evaluadas fueron: el crecimiento (altura y diámetro a la base del tallo), producción de clorofila (cantidad de pigmentos de clorofila a y b), supervivencia, producción y distribución de biomasa total, raíz, rama, hoja y tallo, y arquitectura de crecimiento (largo de rama y altura de inserción de la primera rama) en familias de medios hermanos de P. pseudostrobus evaluados en un ensayo de jardín común a 10 meses de edad bajo tres ambientes de competencia. (I) baja densidad inter-familiar (0.24 × 0.12 m), (II) alta densidad inter-familiar (0.12 × 0.06 m) y (III) alta densidad intra-familiar (0.12 × 0.06 m). Se estimó que los tres componentes con mayor peso (CP) explican el 82.9% de la variación total. El componente principal de mayor varianza se interpreta como crecimiento (CP1), agrupando a las familias por ambiente de competencia; al aumentar la densidad de plantación, posteriormente, las familias se agrupan por la capacidad de supervivencia y por la plasticidad fisiológica (CP2). Finalmente, la diferencia entre los ambientes la hace la plasticidad fenotípica de las familias como respuesta al ambiente de competencia (cambios en la arquitectura) (CP3). Los resultados evidenciaron un elevado nivel de plasticidad fenotípica de P. pseudostrobus y se hace hincapié en la importancia de la selección de ambientes y de genotipos acordes para aumentar la adaptación y productividad en los programas de mejora

    Effects of region of birth, educational level and age on late presentation among men who have sex with men newly diagnosed with HIV in a network of STI/HIV counselling and testing clinics in Spain

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    This paper analyses late presentation (LP) of HIV infection, and its determinants, among men who have sex with men (MSM) in Spain, newly diagnosed with HIV (2003-2011) in 15 sexually transmitted infection/HIV counselling and testing clinics. LP was defined as  12 months before diagnosis (12-24 months (aOR:1.4; 95% CI:1.0-2.0); > 24 months (aOR:2.2; 95% CI:1.7-3.0)). LP was less likely in MSM reporting a known HIV-infected partner as infection source or symptoms compatible with acute retroviral syndrome. 'Region of birth' interacted with 'educational level' and 'steady partner as infection source': only African and Latin-American MSM with low educational level were more likely to present late; Latin-American men attributing their infection to steady partner, but no other MSM, had LP more frequently. In Spain, HIV testing among MSM should be promoted, especially those > 34 years old and migrants with low educational level. The current recommendation that MSM be tested at least once a year is appropriate.This work has been supported with grants No. 36303/02, 36537/05 and 36794/08 from FIPSE (Fundación para la Investigación y la Prevención del Sida en España). The authors wish to thank Kathy Fitch for the English review.S
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