University of Alcalá

About: University of Alcalá is a education organization based out in Alcalá de Henares, Spain. It is known for research contribution in the topics: Population & Context (language use). The organization has 10795 authors who have published 20718 publications receiving 410089 citations. The organization is also known as: University of Alcala & University of Alcala de Henares.

On the specificity of avian blood parasites: revealing specific and generalist relationships between haemosporidians and biting midges

Abstract: The study of host-parasite relationships involving vector-borne parasites requires understanding interactions between parasites and vectors. The capacity of haemosporidians to infect insects has clear evolutionary consequences for the transmission of diseases. Here, we investigated (i) the associations between blood parasites, biting midges and birds and (ii) the potential specificity between biting midge and haemosporidian haplotypes. A total of 629 parous biting midges Culicoides and 224 wild birds (belonging to seven species) from a locality of central Spain were individually examined for the presence of Haemoproteus and Plasmodium parasites by sequencing a fragment of cytochrome B. Biting midges were identified morphologically and characterized on the basis of a fragment of the cytochrome c oxidase (COI) gene. Overall, 12 Haemoproteus and three Plasmodium haplotypes were isolated and sequenced. Among them, 10 haplotypes were exclusively isolated from biting midges, three haplotypes only from birds and two haplotypes from both biting midges and birds. Biting midge haplotypes showed both specific and generalist relationships with Haemoproteus haplotypes but only generalist relationships with Plasmodium haplotypes. Several C. festivipennis and C. kibunesis haplotypes established significant coevolutionary links with Haemoproteus haplotypes. These results shed light on the specificity of interactions between vectors and blood parasites.

A systematic review of post-migration acquisition of HIV among migrants from countries with generalised HIV epidemics living in Europe: mplications for effectively managing HIV prevention programmes and policy

Abstract: Migrant populations from countries with generalised HIV epidemics make up a significant proportion of all HIV/AIDS cases in many European Union and European Economic Area (EU/EEA) countries, with heterosexual transmission the predominant mode of HIV acquisition. While most of these infections are diagnosed for the first time in Europe, acquisition is believed to have predominantly occurred in the home country. A proportion of HIV transmission is believed to be occurring post-migration, and many countries may underestimate the degree to which this is occurring. Our objectives were to review the literature estimating the proportion of migrants believed to have acquired their HIV post-migration and examine which EU member states are able to provide estimates of probable country of HIV acquisition through current surveillance systems. A systematic review was undertaken to gather evidence of sexual transmission of HIV within Europe among populations from countries with a generalised epidemic. In addition, national surveillance focal points from 30 EU/EEA Member States were asked to complete a questionnaire about surveillance methods and monitoring of the likely place of HIV acquisition among migrants. Twenty-seven papers from seven countries were included in the review and 24 countries responded to the survey. Estimates of HIV acquisition post-migration ranged from as low as 2 % among sub Saharan Africans in Switzerland, to 62 % among black Caribbean men who have sex with men (MSM) in the UK. Surveillance methods for monitoring post-migration acquisition varied across the region; a range of methods are used to estimate country or region of HIV acquisition, including behavioural and clinical markers. There is little published evidence addressing this issue, although Member States highlight the importance of migrant populations in their epidemics. There is post-migration HIV acquisition among migrants in European countries but this is difficult to quantify accurately with current data. Migrant MSM appear at particular risk of HIV acquisition post-migration. Countries that identify migrants as an important part of their HIV epidemic should focus on using an objective method for assigning probable country of HIV acquisition. Robust methods to measure HIV incidence should be considered in order to inform national prevention programming and resource allocation.

VIRTUOUS: vision-based road transportation for unmanned operation on urban-like scenarios

Abstract: This work presents an intelligent transportation system (ITS) that was implemented on an autonomous vehicle designed to perform global navigation missions on a network of unmarked roads. This is the first step toward the complete implementation of ITS in urban environments, which is the long-term goal of this work. Using a global positioning system, global navigation is achieved by means of a global planner and a task manager that recurrently coordinate the execution of vision-based perception tasks for the road tracking of nonstructured roads and the navigation of intersections. In addition, a vision-based vehicle-detection task has been developed, which endows the global navigation system with a reactive capacity. The complete system has been tested on the BABIECA prototype vehicle, which was autonomously driven for hundreds of kilometers around a private circuit, designed to emulate an urban quarter, at speeds of up to 50 km/h, successfully carrying out different navigation missions. During the tests, the vehicle drove itself across crossroads and performed the appropriate turning maneuvers at intersections. It also demonstrated its robustness with regard to shadows, road texture, weather conditions, and changing illumination.