Sensitization profiles and cross-reactivity among plant allergens. Molecular mechanisms of food allergy development and the role of enhancers

La prevalencia de las alergias est�� aumentando desde mediados del siglo XX, y se estima que actualmente afectan a alrededor del 2-8 % de la poblaci��n, pero las causas de este aumento a��n no est��n claras. Encontrar el origen del mecanismo por el cual una prote��na inofensiva se convierte en capaz de inducir una respuesta al��rgica es de vital importancia para prevenir y tratar estas enfermedades. Aunque la caracterizaci��n de al��rgenos relevantes ha ayudado a mejorar el manejo cl��nico y a aclarar los mecanismos b��sicos de las reacciones al��rgicas, todav��a queda un largo camino para establecer el origen de la alergenicidad y reactividad cruzada. El objetivo de esta tesis ha sido caracterizar las bases moleculares de la alergenicidad tomando como modelo dos familias de panalergenos (prote��nas de transferencia de l��pidos ���LTPs- y taumatinas ���TLPs-) y estudiando los mecanismos que median la sensibilizaci��n y la reactividad cruzada para mejorar tanto el diagn��stico como el tratamiento de la alergia. Para ello, se llevaron a cabo dos estrategias: estudiar la reactividad cruzada de miembros de familias de panal��rgenos; y estudiar mol��culas-co-adyuvantes que pudieran favorecer la capacidad alerg��nica de dichas prote��nas. Para estudiar la reactividad cruzada entre miembros de la misma familia de prote��nas, se seleccionaron LTPs y TLPs, descritas como alergenos, tomando como modelo la alergia a frutas. Por otra parte, se estudiaron los perfiles de sensibilizaci��n a al��rgenos de trigo relacionados con el asma del panadero, la enfermedad ocupacional m��s relevante de origen al��rgico. Estos estudios se llevaron a cabo estandarizando ensayos tipo microarrays con al��rgenos y analizando los resultados por la teor��a de grafos. En relaci��n al estudiar mol��culas-co-adyuvantes que pudieran favorecer la capacidad alerg��nica de dichas prote��nas, se llevaron a cabo estudios sobre la interacci��n de los al��rgenos alimentarios con c��lulas del sistema inmune humano y murino y el epitelio de las mucosas, analizando la importancia de mol��culas co-transportadas con los al��rgenos en el desarrollo de una respuesta Th2. Para ello, Pru p 3(LTP y al��rgeno principal del melocot��n) se selecci��n como modelo para llevarlo a cabo. Por otra parte, se analiz�� el papel de mol��culas activadoras del sistema inmune producidas por pat��genos en la inducci��n de alergias alimentarias seleccionando el modelo kiwi-alternaria, y el papel de Alt a 1, al��rgeno mayor de dicho hongo, en la sensibilizaci��n a Act d 2, al��rgeno mayor de kiwi. En resumen, el presente trabajo presenta una investigaci��n innovadora aportando resultados de gran utilidad tanto para la mejora del diagn��stico como para nuevas investigaciones sobre la alergia y el esclarecimiento final de los mecanismos que caracterizan esta enfermedad. ABSTRACT Allergies are increasing their prevalence from mid twentieth century, and they are currently estimated to affect around 2-8% of the population but the underlying causes of this increase remain still elusive. The understanding of the mechanism by which a harmless protein becomes capable of inducing an allergic response provides us the basis to prevent and treat these diseases. Although the characterization of relevant allergens has led to improved clinical management and has helped to clarify the basic mechanisms of allergic reactions, it seems justified in aspiring to molecularly dissecting these allergens to establish the structural basis of their allergenicity and cross-reactivity. The aim of this thesis was to characterize the molecular basis of the allergenicity of model proteins belonging to different families (Lipid Transfer Proteins ���LTPs-, and Thaumatin-like Proteins ���TLPs-) in order to identify mechanisms that mediate sensitization and cross reactivity for developing new strategies in the management of allergy, both diagnosis and treatment, in the near future. With this purpose, two strategies have been conducted: studies of cross-reactivity among panallergen families and molecular studies of the contribution of cofactors in the induction of the allergic response by these panallergens. Following the first strategy, we studied the cross-reactivity among members of two plant panallergens (LTPs , Lipid Transfer Proteins , and TLPs , Thaumatin-like Proteins) using the peach allergy as a model. Similarly, we characterized the sensitization profiles to wheat allergens in baker's asthma development, the most relevant occupational disease. These studies were performed using allergen microarrays and the graph theory for analyzing the results. Regarding the second approach, we analyzed the interaction of plant allergens with immune and epithelial cells. To perform these studies , we examined the importance of ligands and co-transported molecules of plant allergens in the development of Th2 responses. To this end, Pru p 3, nsLTP (non-specific Lipid Transfer Protein) and peach major allergen, was selected as a model to investigate its interaction with cells of the human and murine immune systems as well as with the intestinal epithelium and the contribution of its ligand in inducing an allergic response was studied. Moreover, we analyzed the role of pathogen associated molecules in the induction of food allergy. For that, we selected the kiwi- alternaria system as a model and the role of Alt a 1 , major allergen of the fungus, in the development of Act d 2-sensitization was studied. In summary, this work presents an innovative research providing useful results for improving diagnosis and leading to further research on allergy and the final clarification of the mechanisms that characterize this disease.

Interchanging lexical resources on the Semantic Web

Lexica and terminology databases play a vital role in many NLP applications, but currently most such resources are published in application-specific formats, or with custom access interfaces, leading to the problem that much of this data is in ������data silos������ and hence difficult to access. The Semantic Web and in particular the Linked Data initiative provide effective solutions to this problem, as well as possibilities for data reuse by inter-lexicon linking, and incorporation of data categories by dereferencable URIs. The Semantic Web focuses on the use of ontologies to describe semantics on the Web, but currently there is no standard for providing complex lexical information for such ontologies and for describing the relationship between the lexicon and the ontology. We present our model, lemon, which aims to address these gaps

Sharing Human-Generated Observations by Integrating HMI and the Semantic Sensor Web

Current ���Internet of Things��� concepts point to a future where connected objects gather meaningful information about their environment and share it with other objects and people. In particular, objects embedding Human Machine Interaction (HMI), such as mobile devices and, increasingly, connected vehicles, home appliances, urban interactive infrastructures, etc., may not only be conceived as sources of sensor information, but, through interaction with their users, they can also produce highly valuable context-aware human-generated observations. We believe that the great promise offered by combining and sharing all of the different sources of information available can be realized through the integration of HMI and Semantic Sensor Web technologies. This paper presents a technological framework that harmonizes two of the most influential HMI and Sensor Web initiatives: the W3C���s Multimodal Architecture and Interfaces (MMI) and the Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) with its semantic extension, respectively. Although the proposed framework is general enough to be applied in a variety of connected objects integrating HMI, a particular development is presented for a connected car scenario where drivers��� observations about the traffic or their environment are shared across the Semantic Sensor Web. For implementation and evaluation purposes an on-board OSGi (Open Services Gateway Initiative) architecture was built, integrating several available HMI, Sensor Web and Semantic Web technologies. A technical performance test and a conceptual validation of the scenario with potential users are reported, with results suggesting the approach is sound

Combination of optical and on-destructivemechanicaltechniques for the measurement of maturity in peach

Increasing consumer dissatisfaction related with lack of ripeness in peach has been repeatedly reported since 1990 to the present day. There is thus, a great interest in improving the assessment of peach maturity, currently based on Magness Taylor firmness (destructive, highly variable, and time consuming) and colour (not reliable for highly coloured varieties). The present research studies as an alternative several non-destructive (ND) measurements, based on multispectral imaging, visible spectra, and low mass impact response. Their relationship with maturity, as well as the potential of their combination was studied. As a result, two rather independent (R2 = 0.3) groups of non-destructive measurements, chlorophyll related optical indexes and low mass impact (LMI) measurements, were identified. Optical measurements showed the best behaviour for assessing maturity at harvest, while LMI measurements reflected handling incidences, showing a promising potential to be used to control transport and postharvest handling.

Effects of the 4N(v) chromosome from Aegilops ventricosa on agronomic and quality traits in bread wheat

Advanced wheat lines carrying the Hessian fly resistance gene H27 were obtained by backcrossing the wheat/Aegilops ventricosa introgression line, H-93-33, to commercial wheat cultivars as recurrent parents. The Acph-N v 1 marker linked to the gene H27 on the 4Nv chromosome of this line was used for marker assisted selection. Advanced lines were evaluated for Hessian fly resistance in field and growth chamber tests, and for other agronomic traits during several crop seasons at different localities of Spain. The hessian fly resistance levels of lines carrying the 4Nv chromosome introgression (4D/4Nv substitution and recombination lines that previously were classified by in situ hybridisation) were high, but always lower than that of their Ae. ventricosa progenitor. Introgression lines had higher grain yields in infested field trials than those without the 4Nv chromosome and their susceptible parents, but lower grain yields under high yield potential conditions. The 4Nv introgression was also associated with later heading, and lower tiller and grain numbers/m2 . In addition, it was associated with longer and more lax spikes, and higher values of grain weight and grain protein content. However, the glutenin and gliadin expression, as well as the bread-making performance, were similar to those of their recurrent parents

Counting, scoring and classifying hunger to allocate resources targeted to solve the problem

A proper allocation of resources targeted to solve hunger is essential to optimize the efficacy of actions and maximize results. This requires an adequate measurement and formulation of the problem as, paraphrasing Einstein, the formulation of a problem is essential to reach a solution. Different measurement methods have been designed to count, score, classify and compare hunger at local level and to allow comparisons between different places. However, the alternative methods produce significantly reach different results. These discrepancies make decisions on the targeting of resource allocations difficult. To assist decision makers, a new method taking into account the dimension of hunger and the coping capacities of countries, is proposed enabling to establish both geographical and sectoral priorities for the allocation of resources.

Counting, scoring and classifying hunger to allocate resources targeted to solve the problem

A proper allocation of resources targeted to solve hunger is essential to optimize the efficacy of actions and maximize results. This requires an adequate measurement and formulation of the problem as, paraphrasing Einstein, the formulation of a problem is essential to reach a solution. Different measurement methods have been designed to count, score, classify and compare hunger at local level and to allow comparisons between different places. However, the alternative methods reach significantly different results. These discrepancies make decisions on the targeting of resource allocations difficult. To assist decision makers, a new method taking into account the dimension of hunger and the coping capacities of countries is proposed enabling to establish both geographical and sectoral priorities for the allocation of resources

Challenges for the Multilingual Web of Data

The Web has witnessed an enormous growth in the amount of semantic information published in recent years. This growth has been stimulated to a large extent by the emergence of Linked Data. Although this brings us a big step closer to the vision of a Semantic Web, it also raises new issues such as the need for dealing with information expressed in different natural languages. Indeed, although the Web of Data can contain any kind of information in any language, it still lacks explicit mechanisms to automatically reconcile such information when it is expressed in different languages. This leads to situations in which data expressed in a certain language is not easily accessible to speakers of other languages. The Web of Data shows the potential for being extended to a truly multilingual web as vocabularies and data can be published in a language-independent fashion, while associated language-dependent (linguistic) information supporting the access across languages can be stored separately. In this sense, the multilingual Web of Data can be realized in our view as a layer of services and resources on top of the existing Linked Data infrastructure adding i) linguistic information for data and vocabularies in different languages, ii) mappings between data with labels in different languages, and iii) services to dynamically access and traverse Linked Data across different languages. In this article we present this vision of a multilingual Web of Data. We discuss challenges that need to be addressed to make this vision come true and discuss the role that techniques such as ontology localization, ontology mapping, and cross-lingual ontology-based information access and presentation will play in achieving this. Further, we propose an initial architecture and describe a roadmap that can provide a basis for the implementation of this vision.

Effect of short-term fasting prior to slaughter on welfare and meat quality or rainbow trout (Oncorhynchus mykiss)

El manejo pre-sacrificio es de vital importancia en acuicultura, ya que afecta tanto a las reacciones fisiol��gicas como a los procesos bioqu��micos post mortem, y por tanto al bienestar y a la calidad del producto. El ayuno pre-sacrificio se lleva a cabo de forma habitual en acuicultura, ya que permite el vaciado del aparato digestivo de restos de alimento y heces, reduciendo de esta manera la carga bacteriana en el intestino y la dispersi��n de enzimas digestivos y potenciales pat��genos a la carne. Sin embargo, la duraci��n ��ptima de este ayuno sin que el pez sufra un estr��s innecesario no est�� clara. Adem��s, se sabe muy poco sobre la mejor hora del d��a para realizar el sacrificio, lo que a su vez est�� regido por los ritmos diarios de los par��metros fisiol��gicos de estr��s. Finalmente, se sabe que la temperatura del agua juega un papel muy importante en la fisiolog��a del estr��s pero no se ha determinado su efecto en combinaci��n con el ayuno. Adem��s, las actuales recomendaciones en relaci��n a la duraci��n ��ptima del ayuno previo al sacrificio en peces no suelen considerar la temperatura del agua y se basan ��nicamente en d��as y no en grados d��a (��C d). Se determin�� el efecto del ayuno previo al sacrificio (1, 2 y 3 d��as, equivalente a 11,1-68,0 grados d��a) y la hora de sacrificio (08h00, 14h00 y 20h00) en trucha arco iris (Oncorhynchus mykiss) de tama��o comercial en cuatro pruebas usando diferentes temperaturas de agua (Prueba 1: 11,8 ��C; Prueba 2: 19,2 ��C; Prueba 3: 11,1 ��C; y Prueba 4: 22,7 ��C). Se midieron indicadores biom��tricos, hematol��gicos, metab��licos y de calidad de la carne. En cada prueba, los valores de los animales ayunados (n=90) se compararon con 90 animales control mantenidos bajo condiciones similares pero nos ayunados. Los resultados sugieren que el ayuno tuvo un efecto significativo sobre los indicadores biom��tricos. El coeficiente de condici��n en los animales ayunados fue menor que en los controles despu��s de 2 d��as de ayuno. El vaciado del aparato digestivo se produjo durante las primeras 24 h de ayuno, encontr��ndose peque��as cantidades de alimento despu��s de 48 h. Por otra parte, este vaciado fue m��s r��pido cuando las temperaturas fueron m��s altas. El peso del h��gado de los animales ayunados fue menor y las diferencias entre truchas ayunadas y controles fueron m��s evidentes a medida que el vaciado del aparato digestivo fue m��s r��pido. El efecto del ayuno hasta 3 d��as en los indicadores hematol��gicos no fue significativo. Los niveles de cortisol en plasma resultaron ser altos tanto en truchas ayunadas como en las alimentadas en todas las pruebas realizadas. La concentraci��n media de glucosa vari�� entre pruebas pero mostr�� una tendencia a disminuir en animales ayunados a medida que el ayuno progresaba. En cualquier caso, parece que la temperatura del agua jug�� un papel muy importante, ya que se encontraron concentraciones m��s altas durante los d��as 2 y 3 de ayuno en animales mantenidos a temperaturas m��s bajas previamente al sacrificio. Los altos niveles de lactato obtenidos en sangre parecen sugerir episodios de intensa actividad muscular pero no se pudo encontrar relaci��n con el ayuno. De la misma manera, el nivel de hematocrito no mostr�� efecto alguno del ayuno y los leucocitos tendieron a ser m��s altos cuando los animales estaban menos estresados y cuando su condici��n corporal fue mayor. Finalmente, la disminuci��n del peso del h��gado (��ndice hepatosom��tico) en la Prueba 3 no se vio acompa��ada de una reducci��n del gluc��geno hep��tico, lo que sugiere que las truchas emplearon una estrategia diferente para mantener constantes los niveles de glucosa durante el periodo de ayuno en esa prueba. En relaci��n a la hora de sacrificio, se obtuvieron niveles m��s bajos de cortisol a las 20h00, lo que indica que las truchas estaban menos estresadas y que el manejo pre-sacrificio podr��a resultar menos estresante por la noche. Los niveles de hematocrito fueron tambi��n m��s bajos a las 20h00 pero solo con temperaturas m��s bajas, sugiriendo que las altas temperaturas incrementan el metabolismo. Ni el ayuno ni la hora de sacrificio tuvieron un efecto significativo sobre la evoluci��n de la calidad de la carne durante los 3 d��as de almacenamiento. Por el contrario, el tiempo de almacenamiento s�� que parece tener un efecto claro sobre los par��metros de calidad del producto final. Los niveles m��s bajos de pH se alcanzaron a las 24-48 h post mortem, con una lata variabilidad entre duraciones del ayuno (1, 2 y 3 d��as) en animales sacrificados a las 20h00, aunque no se pudo distinguir ning��n patr��n com��n. Por otra parte, la mayor rigidez asociada al rigor mortis se produjo a las 24 h del sacrificio. La capacidad de retenci��n de agua se mostr�� muy estable durante el per��odo de almacenamiento y parece ser independiente de los cambios en el pH. El par��metro L* de color se increment�� a medida que avanzaba el per��odo de almacenamiento de la carne, mientras que los valores a* y b* no variaron en gran medida. En conclusi��n, bas��ndose en los resultados hematol��gicos, el sacrificio a ��ltima hora del d��a parece tener un efecto menos negativo en el bienestar. De manera general, nuestros resultados sugieren que la trucha arco iris puede soportar un per��odo de ayuno previo al sacrificio de hasta 3 d��as o 68 ��C d sin que su bienestar se vea seriamente comprometido. Es probable que con temperaturas m��s bajas las truchas pudieran ser ayunadas durante m��s tiempo sin ning��n efecto negativo sobre su bienestar. En cualquier caso, se necesitan m��s estudios para determinar la relaci��n entre la temperatura del agua y la duraci��n ��ptima del ayuno en t��rminos de p��rdida de peso vivo y la disminuci��n de los niveles de glucosa en sangre y otros indicadores metab��licos. SUMMARY Pre-slaughter handling in fish is important because it affects both physiological reactions and post mortem biochemical processes, and thus welfare and product quality. Pre-slaughter fasting is regularly carried out in aquaculture, as it empties the viscera of food and faeces, thus reducing the intestinal bacteria load and the spread of gut enzymes and potential pathogens to the flesh. However, it is unclear how long rainbow trout can be fasted before suffering unnecessary stress. In addition, very little is known about the best time of the day to slaughter fish, which may in turn be dictated by diurnal rhythms in physiological stress parameters. Water temperature is also known to play a very important role in stress physiology in fish but the combined effect with fasting is unclear. Current recommendations regarding the optimal duration of pre-slaughter fasting do not normally consider water temperature and are only based on days, not degree days (��C d). The effects of short-term fasting prior to slaughter (1, 2 and 3 days, between 11.1 and 68.0 ��C days) and hour of slaughter (08h00, 14h00 and 20h00) were determined in commercial-sized rainbow trout (Oncorhynchus mykiss) over four trials at different water temperatures (TRIAL 1, 11.8 ��C; TRIAL 2, 19.2 ��C; TRIAL 3, 11.1 ��C; and TRIAL 4, 22.7 ��C). We measured biometric, haematological, metabolic and product quality indicators. In each trial, the values of fasted fish (n=90) were compared with 90 control fish kept under similar conditions but not fasted. Results show that fasting affected biometric indicators. The coefficient of condition in fasted trout was lower than controls 2 days after food deprivation. Gut emptying occurred within the first 24 h after the cessation of feeding, with small traces of digesta after 48 h. Gut emptying was faster at higher water temperatures. Liver weight decreased in food deprived fish and differences between fasted and fed trout were more evident when gut clearance was faster. The overall effect of fasting for up to three days on haematological indicators was small. Plasma cortisol levels were high in both fasted and fed fish in all trials. Plasma glucose response to fasting varied among trials, but it tended to be lower in fasted fish as the days of fasting increased. In any case, it seems that water temperature played a more important role, with higher concentrations at lower temperatures on days 2 and 3 after the cessation of feeding. Plasma lactate levels indicate moments of high muscular activity and were also high, but no variation related to fasting could be found. Haematocrit did not show any significant effect of fasting, but leucocytes tended to be higher when trout were less stressed and when their body condition was higher. Finally, the loss of liver weight was not accompanied by a decrease in liver glycogen (only measured in TRIAL 3), suggesting that a different strategy to maintain plasma glucose levels was used. Regarding the hour of slaughter, lower cortisol levels were found at 20h00, suggesting that trout were less stressed later in the day and that pre-slaughter handling may be less stressful at night. Haematocrit levels were also lower at 20h00 but only at lower temperatures, indicating that higher temperatures increase metabolism. Neither fasting nor the hour of slaughter had a significant effect on the evolution of meat quality during 3 days of storage. In contrast, storage time seemed to have a more important effect on meat quality parameters. The lowest pH was reached 24-48 h post mortem, with a higher variability among fasting durations at 20h00, although no clear pattern could be discerned. Maximum stiffening from rigor mortis occurred after 24 h. The water holding capacity was very stable throughout storage and seemed to be independent of pH changes. Meat lightness (L*) slightly increased during storage and a* and b*-values were relatively stable. In conclusion, based on the haematological results, slaughtering at night may have less of a negative effect on welfare than at other times of the day. Overall, our results suggest that rainbow trout can cope well with fasting up to three days or 68 ��C d prior to slaughter and that their welfare is therefore not seriously compromised. At low water temperatures, trout could probably be fasted for longer periods without negative effects on welfare but more research is needed to determine the relationship between water temperature and days of fasting in terms of loss of live weight and the decrease in plasma glucose and other metabolic indicators.

Effects of high hydrostatic pressure on rheological and termal properties of chickpea Cicer arietinum L. flour slurry and heat-induced paste.

Thermorheological changes in high hydrostatic pressure (HHP)-treated chickpea flour (CF) slurries were studied as a function of pressure level (0.1, 150, 300, 400, and 600 MPa) and slurry concentration (1:5, 1:4, 1:3, and 1:2 flour-to-water ratios). HHP-treated slurries were subsequently analyzed for changes in properties produced by heating, under both isothermal and non-isothermal processes. Elasticity (G���) of pressurized slurry increased with pressure applied and concentration. Conversely, heat-induced CF paste gradually transformed from solid-like behavior to liquid-like behavior as a function of moisture content and pressure level. The G��� and enthalpy of the CF paste decreased with increasing pressure level in proportion with the extent of HHP-induced starch gelatinization. At 25 ��C and 15 min, HHP treatment at 450 and 600 MPa was sufficient to complete gelatinization of CF slurry at the lowest concentration (1:5), while more concentrated slurries would require higher pressures and temperature during treatment or longer holding times. Industrial relevance Demand for chickpea gel has increased considerably in the health and food industries because of its many beneficial effects. However, its use is affected by its very difficult handling. Judicious application of high hydrostatic pressure (HHP) at appropriate levels, adopted as a pre-processing instrument in combination with heating processes, is presented as an innovative technology to produce a remarkable decrease in thermo-hardening of heat-induced chickpea flour paste, permitting the development of new chickpea-based products with desirable handling properties and sensory attributes.

Analysis of a rate-adaptive reconciliation protocol and the effect of leakage on the secret key rate

Quantum key distribution performs the trick of growing a secret key in two distant places connected by a quantum channel. The main reason is so that the legitimate users can bound the information gathered by the eavesdropper. In practical systems, whether because of finite resources or external conditions, the quantum channel is subject to fluctuations. A rate-adaptive information reconciliation protocol, which adapts to the changes in the communication channel, is then required to minimize the leakage of information in the classical postprocessing. We consider here the leakage of a rate-adaptive information reconciliation protocol. The length of the exchanged messages is larger than that of an optimal protocol; however, we prove that the min-entropy reduction is limited. The simulation results, both in the asymptotic and in the finite-length regime, show that this protocol allows to increase the amount of a distillable secret key.

Farmers behaviour on mitigation and adaptation to climate change: A case study in Kenya.

Farmers in Africa are facing climate change and challenging rural livelihoods while maintaining agricultural systems that are not resilient. By 2050 the mean estimates of production of key staple crops in Africa such as maize, sorghum, millet, groundnut, and cassava are expected to decrease by between 8 and 22 percent (Schlenker and Lobell 2010). In Kenya, although projections of rainfall do not show dramatic decreases, the distribution of impacts is clearly negative for most crops. As increases in temperature will lead to increases in evapotranspiration, a potential increase in rainfall in Kenya may not offset the expected increases in agricultural water needs (Herrero et al. 2010). In order to respond to these present and future challenges, potential mitigation and adaptation options have been developed. However, implementation is not evident. In addition to their benefits in either mitigating or reducing the vulnerability of climate change effects, many of these options do not have economic costs and even provide economic benefits (e.g. savings in the consumption of energy or natural resources). Nevertheless, it is demonstrated that even when there are no biophysical, technological or economic constraints and despite their potential benefits from either the economic or environmental climate change point of view, not all farmers are willing to adopt these measures. This reflects the key role that behavioural barriers can play in the uptake of mitigation and adaptation measures.

Numerical model for the study of hydrodynamics on bays and estuaries

A nonlinear implicit finite element model for the solution of two-dimensional (2-D) shallow water equations, based on a Galerkin formulation of the 2-D estuaries hydrodynamic equations, has been developed. Spatial discretization has been achieved by the use of isoparametric, Lagrangian elements. To obtain the different element matrices, Simpson numerical integration has been applied. For time integration of the model, several schemes in finite differences have been used: the Cranck-Nicholson iterative method supplies a superior accuracy and allows us to work with the greatest time step ��t; however, central differences time integration produces a greater velocity of calculation. The model has been tested with different examples to check its accuracy and advantages in relation to computation and handling of matrices. Finally, an application to the Bay of Santander is also presented.

Accessing and managing open medical resources in Africa over the Internet

Recent commentaries have proposed the advantages of using open exchange of data and informatics resources for improving health-related policies and patient care in Africa. Yet, in many African regions, both private medical and public health information systems are still unaffordable. Open exchange over the social Web 2.0 could encourage more altruistic support of medical initiatives. We have carried out some experiments to demonstrate the feasibility of using this approach to disseminate open data and informatics resources in Africa. After the experiments we developed the AFRICA BUILD Portal, the first Social Network for African biomedical researchers. Through the AFRICA BUILD Portal users can access in a transparent way to several resources. Currently, over 600 researchers are using distributed and open resources through this platform committed to low connections.

A multi-scale analysis of transforming agricultural markets in the context of globalization: implications for natural resources, food prices and rural poverty in Latin America

Vivimos una ��poca en la que el mundo se transforma aceleradamente. La globalizaci��n est�� siguiendo un curso imparable, la poblaci��n mundial as�� como la poblaci��n urbana siguen creciendo, y en los pa��ses emergentes los ingresos promedios aumentan, resultando en un cambio tambi��n acelerado de las dietas y h��bitos alimentarios. En conjunto esos factores est��n causando un aumento fundamental de la demanda de alimentos. Junto con la apertura de los mercados agr��colas, estos procesos han provocado un crecimiento del comercio internacional de alimentos durante la ��ltima d��cada. Dado que muchos pa��ses de Am��rica Latina est��n dotados de abundancia de recursos naturales, estas tendencias han producido un crecimiento r��pido de las exportaciones de bienes primarios desde Am��rica Latina al resto del mundo. En s��lo 30 a��os la participaci��n en el mercado agr��cola de Am��rica Latina casi se ha duplicado, desde 10% en 1980 a 18% en 2010. Este aumento del comercio agr��cola ha dado lugar a un debate sobre una serie de cuestiones cruciales relacionadas con los impactos del comercio en la seguridad alimentaria mundial, en el medio ambiente o en la reducci��n de la pobreza rural en pa��ses en desarrollo. Esta tesis aplica un marco integrado para analizar varios impactos relacionados con la transformaci��n de los mercados agr��colas y los mercados rurales debidos a la globalizaci��n y, en particular, al progresivo aumento del comercio internacional. En concreto, la tesis aborda los siguientes temas: En primer lugar, la producci��n mundial de alimentos tendr�� que aumentar considerablemente para poder satisfacer la demanda de una poblaci��n mundial de 9000 millones personas en 2050, lo cual plantea grandes desaf��os sobre los sistemas de la producci��n de alimentos. Alcanzar este logro, sin comprometer la integridad del medio ambiente en regiones exportadoras, es un reto a��n mayor. En este contexto, la tesis analiza los efectos de la liberalizaci��n del comercio mundial, considerando distintas tecnolog��as de producci��n agraria, sobre unos indicadores de seguridad alimentaria en diferentes regiones del mundo y sobre distintos indicadores ambientales, teniendo en cuenta escalas diferentes en Am��rica Latina y el Caribe. La tesis utiliza el modelo ���International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT)��� ��� un modelo din��mico de equilibrio parcial del sector agr��cola a escala global ��� para modelar la apertura de los mercados agr��colas as�� como diferentes escenarios de la producci��n hasta el a��o 2050. Los resultados del modelo est��n vinculados a modelos biof��sicos para poder evaluar los cambios en la huella h��drica y la calidad del agua, as�� como para cuantificar los impactos del cambio en el uso del suelo sobre la biodiversidad y los stocks de carbono en 2050. Los resultados indican que la apertura de los mercados agr��colas es muy importante para mejorar la seguridad alimentaria a nivel mundial, sin embargo, produce tambi��n presiones ambientales indeseables en algunas regiones de Am��rica Latina. Contrastando dos escenarios que consideran distintas modos de producci��n, la expansi��n de la tierra agr��cola frente a un escenario de la producci��n m��s intensiva, se demuestra que las mejoras de productividad son generalmente superiores a la expansi��n de las tierras agr��colas, desde un punto de vista econ��mico e ambiental. En cambio, los escenarios de intensificaci��n sostenible no s��lo hacen posible una mayor producci��n de alimentos, sino que tambi��n generan menos impactos medioambientales que los otros escenarios futuros en todas sus dimensiones: biodiversidad, carbono, emisiones de nitratos y uso del agua. El an��lisis muestra que hay un ���trade-off��� entre el objetivo de alcanzar la sostenibilidad ambiental y el objetivo de la seguridad alimentaria, independiente del manejo agr��cola en el futuro. En segundo lugar, a la luz de la reciente crisis de los precios de alimentos en los a��os 2007/08, la tesis analiza los impactos de la apertura de los mercados agr��colas en la transmisi��n de precios de los alimentos en seis pa��ses de Am��rica Latina: Argentina, Brasil, Chile, Colombia, M��xico y el Per��. Para identificar las posibles relaciones de cointegraci��n entre los ��ndices de precios al consumidor de alimentos y los ��ndices de precios de agrarios internacionales, sujetos a diferentes grados de apertura de mercados agr��colas en los seis pa��ses de Am��rica Latina, se utiliza un modelo simple de correcci��n de error (single equation error correction). Los resultados indican que la integraci��n global de los mercados agr��colas ha dado lugar a diferentes tasas de transmisi��n de precios en los pa��ses investigados. Sobre todo en el corto plazo, las tasas de transmisi��n dependen del grado de apertura comercial, mientras que en el largo plazo las tasas de transmisi��n son elevadas, pero en gran medida independientes del r��gimen de comercio. Por lo tanto, durante un per��odo de shocks de precios mundiales una mayor apertura del comercio trae consigo m��s inestabilidad de los precios dom��sticos a corto plazo y la resultante persistencia en el largo plazo. Sin embargo, estos resultados no verifican necesariamente la utilidad de las pol��ticas comerciales, aplicadas frecuentemente por los gobiernos para amortiguar los shocks de precios. Primero, porque existe un riesgo considerable de volatilidad de los precios debido a cambios bruscos de la oferta nacional si se promueve la autosuficiencia en el pa��s; y segundo, la pol��tica de proteccionismo asume el riesgo de excluir el pa��s de participar en las cadenas de suministro de alto valor del sector agr��cola, y por lo tanto esa pol��tica podr��a obstaculizar el desarrollo econ��mico. Sin embargo, es indispensable establecer pol��ticas efectivas para reducir la vulnerabilidad de los hogares a los aumentos repentinos de precios de alimentos, lo cual requiere una planificaci��n gubernamental precisa con el presupuesto requerido disponible. En tercer lugar, la globalizaci��n afecta a la estructura de una econom��a y, por medios distintos, la distribuci��n de los ingreso en un pa��s. Per�� sirve como ejemplo para investigar m��s profundamente las cuestiones relacionadas con los cambios en la distribuci��n de los ingresos en zonas rurales. Per��, que es un pa��s que est�� cada vez m��s integrado en los mercados mundiales, consigui�� importantes descensos en la pobreza extrema en sus zonas rurales, pero a la vez adolece de alta incidencia de pobreza moderada y de desigualdad de los ingresos en zonas rural al menos durante el periodo comprendido entre 2004 y 2012. Esta parte de la tesis tiene como objetivo identificar las fuerzas impulsoras detr��s de estas din��micas en el Per�� mediante el uso de un modelo de microsimulaci��n basado en modelos de generaci��n de ingresos aplicado a nivel los hogares rurales. Los resultados indican que la fuerza principal detr��s de la reducci��n de la pobreza ha sido el crecimiento econ��mico general de la econom��a, debido a las condiciones macroecon��micas favorables durante el periodo de estudio. Estos efectos de crecimiento beneficiaron a casi todos los sectores rurales, y dieron lugar a la disminuci��n de la pobreza rural extrema, especialmente entre los agricultores de papas y de ma��z. En parte, estos agricultores probablemente se beneficiaron de la apertura de los mercados agr��colas, que es lo que podr��a haber provocado un aumento de los precios al productor en tiempos de altos precios mundiales de los alimentos. Sin embargo, los resultados tambi��n sugieren que para una gran parte de la poblaci��n m��s pobre exist��an barreras de entrada a la hora de poder participar en el empleo asalariado fuera de la agricultura o en la producci��n de cultivos de alto valor. Esto podr��a explicarse por la falta de acceso a unos activos importantes: por ejemplo, el nivel de educaci��n de los pobres era apenas mejor en 2012 que en 2004; y tambi��n las dotaciones de tierra y de mano de obra, sobre todo de los productores pobres de ma��z y patata, disminuyeron entre 2004 y 2012. Esto lleva a la conclusi��n de que a��n hay margen para aplicar pol��ticas para facilitar el acceso a estos activos, que podr��a contribuir a la erradicaci��n de la pobreza rural. La tesis concluye que el comercio agr��cola puede ser un importante medio para abastecer una poblaci��n mundial creciente y m��s rica con una cantidad suficiente de calor��as. Para evitar adversos efectos ambientales e impactos negativos para los consumidores y de los productores pobres, el enfoque debe centrarse en las mejoras de la productividad agr��cola, teniendo en cuenta los l��mites ambientales y ser socialmente inclusivo. En este sentido, ser�� indispensable seguir desarrollando soluciones tecnol��gicas que garanticen pr��cticas de producci��n agr��cola minimizando el uso de recursos naturales. Adem��s, para los peque��os pobres agricultores ser�� fundamental eliminar las barreras de entrada a los mercados de exportaci��n que podr��a tener efectos indirectos favorables a trav��s de la adopci��n de nuevas tecnolog��as alcanzables a trav��s de mercados internacionales. ABSTRACT The world is in a state of rapid transition. Ongoing globalization, population growth, rising living standards and increasing urbanization, accompanied by changing dietary patterns throughout the world, are increasing the demand for food. Together with more open trade regimes, this has triggered growing international agricultural trade during the last decade. For many Latin American countries, which are gifted with relative natural resource abundance, these trends have fueled rapid export growth of primary goods. In just 30 years, the Latin American agricultural market share has almost doubled from 10% in 1980 to 18% in 2010. These market developments have given rise to a debate around a number of crucial issues related to the role of agricultural trade for global food security, for the environment or for poverty reduction in developing countries. This thesis uses an integrated framework to analyze a broad array of possible impacts related to transforming agricultural and rural markets in light of globalization, and in particular of increasing trade activity. Specifically, the following issues are approached: First, global food production will have to rise substantially by the year 2050 to meet effective demand of a nine billion people world population which poses major challenges to food production systems. Doing so without compromising environmental integrity in exporting regions is an even greater challenge. In this context, the thesis explores the effects of future global trade liberalization on food security indicators in different world regions and on a variety of environmental indicators at different scales in Latin America and the Caribbean, in due consideration of different future agricultural production practices. The International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT) ���a global dynamic partial equilibrium model of the agricultural sector developed by the International Food Policy Research Institute (IFPRI)��� is applied to run different future production scenarios, and agricultural trade regimes out to 2050. Model results are linked to biophysical models, used to assess changes in water footprints and water quality, as well as impacts on biodiversity and carbon stocks from land use change by 2050. Results indicate that further trade liberalization is crucial for improving food security globally, but that it would also lead to more environmental pressures in some regions across Latin America. Contrasting land expansion versus more intensified agriculture shows that productivity improvements are generally superior to agricultural land expansion, from an economic and environmental point of view. Most promising for achieving food security and environmental goals, in equal measure, is the sustainable intensification scenario. However, the analysis shows that there are trade-offs between environmental and food security goals for all agricultural development paths. Second, in light of the recent food price crisis of 2007/08, the thesis looks at the impacts of increasing agricultural market integration on food price transmission from global to domestic markets in six Latin American countries, namely Argentina, Brazil, Chile, Colombia, Mexico and Peru. To identify possible cointegrating relationships between the domestic food consumer price indices and world food price levels, subject to different degrees of agricultural market integration in the six Latin American countries, a single equation error correction model is used. Results suggest that global agricultural market integration has led to different levels of price path-through in the studied countries. Especially in the short-run, transmission rates depend on the degree of trade openness, while in the long-run transmission rates are high, but largely independent of the country-specific trade regime. Hence, under world price shocks more trade openness brings with it more price instability in the short-term and the resulting persistence in the long-term. However, these findings do not necessarily verify the usefulness of trade policies, often applied by governments to buffer such price shocks. First, because there is a considerable risk of price volatility due to domestic supply shocks if self-sufficiency is promoted. Second, protectionism bears the risk of excluding a country from participating in beneficial high-value agricultural supply chains, thereby hampering economic development. Nevertheless, to reduce households��� vulnerability to sudden and large increases of food prices, effective policies to buffer food price shocks should be put in place, but must be carefully planned with the required budget readily available. Third, globalization affects the structure of an economy and, by different means, the distribution of income in a country. Peru serves as an example to dive deeper into questions related to changes in the income distribution in rural areas. Peru, a country being increasingly integrated into global food markets, experienced large drops in extreme rural poverty, but persistently high rates of moderate rural poverty and rural income inequality between 2004 and 2012. The thesis aims at disentangling the driving forces behind these dynamics by using a microsimulation model based on rural household income generation models. Results provide evidence that the main force behind poverty reduction was overall economic growth of the economy due to generally favorable macroeconomic market conditions. These growth effects benefited almost all rural sectors, and led to declines in extreme rural poverty, especially among potato and maize farmers. In part, these farmers probably benefited from policy changes towards more open trade regimes and the resulting higher producer prices in times of elevated global food price levels. However, the results also suggest that entry barriers existed for the poorer part of the population to participate in well-paid wage-employment outside of agriculture or in high-value crop production. This could be explained by a lack of sufficient access to important rural assets. For example, poor people���s educational attainment was hardly better in 2012 than in 2004. Also land and labor endowments, especially of (poor) maize and potato growers, rather decreased than increased over time. This leads to the conclusion that there is still scope for policy action to facilitate access to these assets, which could contribute to the eradication of rural poverty. The thesis concludes that agricultural trade can be one important means to provide a growing and richer world population with sufficient amounts of calories. To avoid adverse environmental effects and negative impacts for poor food consumers and producers, the focus should lie on agricultural productivity improvements, considering environmental limits and be socially inclusive. In this sense, it will be crucial to further develop technological solutions that guarantee resource-sparing agricultural production practices, and to remove entry barriers for small poor farmers to export markets which might allow for technological spill-over effects from high-value global agricultural supply chains.